Publications by authors named "Premkumar Kumpati"

41 Publications

Integrative miRNA-mRNA functional analysis identifies miR-182 as a potential prognostic biomarker in breast cancer.

Mol Omics 2021 Apr 22. Epub 2021 Apr 22.

Department of Biomedical Science, School of Biotechnology and Genetic Engineering, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India.

Breast cancer (BC) is a heterogeneous disease distinct from major clinical hindrances, and microRNAs (miRNAs) have been accounted to partake in BC progression. Identifying potential miRNAs and their pathological significance in BC could pave the way for precisely targeted treatments. This study exploits transcriptomic BC miRNA, mRNA cohorts, and prognostic significance via an integrative functional approach. miRNA transcriptomic cohorts (GSE45666, GSE40267, and GSE19783) were utilized to disseminate differentially expressed miRNAs (DEmiRNAs) and their expression in the clinicopathological variables of BC. miR-182 was identified as a potent candidate, differentially expressed between each BC stage and its adjacent normal samples. The expression of miR-182 was significantly associated with estrogen receptor (ER) (p = 0.052), and closely related to progesterone receptor (PR) (p = 0.061) and human epidermal growth factor receptor 2 (Her2) (p = 0.077). miRNA-mRNA regulatory targets were predicted using six different databases, namely, TargetScan, miRDB, Diana, miRNet, TargetMiner, and miRWalk. Twenty-four promising mRNA regulatory targets were potentially identified for miR-182 and thus highly enriched with cellular metabolic processes, proteoglycans, and focal adhesion pathways in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) terms. Subsequently, the F-box and WD repeat domain containing 7, E3 ubiquitin protein ligase (FBXW7) gene was recognized as a hub with the highest connectivity score in the protein-protein interaction network. Furthermore, miR-182 and FBXW7 were associated with poor prognostic clinical outcomes in BC patients. Thus, our integrated functional analysis suggests that miR-182 might lead to a new therapeutic target in BC manifestation.
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http://dx.doi.org/10.1039/d0mo00160kDOI Listing
April 2021

Systemic Multi-Omics Analysis Reveals Amplified P4HA1 Gene Associated With Prognostic and Hypoxic Regulation in Breast Cancer.

Front Genet 2021 22;12:632626. Epub 2021 Feb 22.

Department of Biomedical Science, School of Biotechnology and Genetic Engineering, Bharathidasan University, Tiruchirappalli, India.

Breast cancer (BC) is a common malignant tumor in females around the world. While multimodality therapies exist, the mortality rate remains high. The hypoxic condition was one of the potent determinants in BC progression. The molecular mechanisms underpinning hypoxia and their association with BC can contribute to a better understanding of tailored therapies. In this study, two hypoxic induced BC transcriptomic cohorts (GSE27813 and GSE47533) were assessed from the GEO database. The P4HA1 gene was identified as a putative candidate and significantly regulated in hypoxic BC cells compared to normal BC cells at different time intervals (6 h, 9 h, 16 h, 32 h, and 48 h). In patients with Luminal ( < 1E-12), triple-negative subclasses ( = 1.35059E-10), Stage 1 ( = 8.8817E-16), lymph node N1 ( = 1.62436E-12), and in the 40-80 age group ( = 1.62447E-12), the expression of P4HA1 was closely associated with the clinical subtypes of BC. Furthermore, at the 10q22.1 chromosomal band, the P4HA1 gene displayed a high copy number elevation and was associated with a poor clinical regimen with overall survival, relapse-free survival, and distant metastases-free survival in BC patients. In addition, using BioGRID, the protein-protein interaction (PPI) network was built and the cellular metabolic processes, and hedgehog pathways are functionally enriched with GO and KEGG terms. This tentative result provides insight into the molecular function of the P4HA1 gene, which is likely to promote hypoxic-mediated carcinogenesis, which may favor early detection of BC and therapeutic stratification.
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http://dx.doi.org/10.3389/fgene.2021.632626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7937963PMC
February 2021

Pharmacophore based virtual screening, molecular docking and molecular dynamic simulation studies for finding ROS1 kinase inhibitors as potential drug molecules.

J Biomol Struct Dyn 2020 Nov 17:1-15. Epub 2020 Nov 17.

Department of Biomedical Science, Bharathidasan University, Tamil Nadu, India.

Proto-oncogene receptor tyrosine kinase ROS-1 is one of the clinically important biomarker and plays a crucial role in regulation of a number of cellular functions including cell proliferation, migration and angiogenesis. Recently, inhibition of ROS1 kinase has proven to be a promising target of anticancer drugs for non-small cell lung cancer (NSCLC). The very few compounds have been used as potent drug molecules so far and the selective ROS1 inhibitors are relatively rare. Besides the currently available drugs such as Crizotinib and PF-06463922 are becoming sensitive due to mutations in the ROS1 protein. To curtail the problem of the resistant, present study was designed to identify the potent inhibitors against ROS1. Three different screening approaches such as structure based, Atom-based and pharmacophore based screening were carried out against commercially available databases and the retrieved best hits were further evaluated by Lipinski's filter. Thereafter the lead molecule was subjected to pocket specific docking with ROS1. The results show that, total of 9 molecules (3 from each screening) has good docking score (with range of -9.288 to -12.49 Kcal/Mol) and binding interactions within the active site of ROS1. In order to analyze the stability of the ligand- protein complexes, molecular dynamics simulation was performed. Thus, these identified potential lead molecules with good binding score and binding affinity with ROS1 may act as the potent ROS1 inhibitor, and that are worth considering for further experimental studies.Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2020.1847195DOI Listing
November 2020

The remarkable role of emulsifier and chitosan, dextran and PEG as capping agents in the enhanced delivery of curcumin by nanoparticles in breast cancer cells.

Int J Biol Macromol 2020 Nov 23;162:748-761. Epub 2020 Jun 23.

Department of Inorganic Chemistry, Guindy Campus, University of Madras, Chennai 600025, India. Electronic address:

Curcumin has been found to be a powerful anti-cancer agent. However, its efficacy is limited by its poor solubility in aqueous medium. The bioavailability of curcumin was increased by poly (lactic-co-glycolic) acid [PLGA (60/40)] nanoparticles with different capping agents such as Chitosan, Dextran and PEG and emulsifier (Tocopherol Poly (Ethylene Glycol)1000 Succinate: TPGS) with good drug loading and delivery performance. The preparation of nanoparticles derived from PLGA was achieved by emulsion solvent evaporation method and the resultant nanoparticles were characterized. The encapsulation efficiency of curcumin by PLGA NPs with different capping agents such as Chitosan, PEG and Dextran and emulsifier lies in the range of 82% to 89% and the anti-oxidant activity is 80%. The in vitro anticancer activity of PLGA nanoparticles embedded with curcumin and different capping agents on MCF-7 indicates that they are more effective in arresting cell growth. The cellular uptake of TPGS emulsified dextran capped curcumin encapsulated PLGA NPs is much higher when compared to that of PLGA NPs with other capping agents, emulsifier and free curcumin.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.06.188DOI Listing
November 2020

Nannochloropsis Extract-Mediated Synthesis of Biogenic Silver Nanoparticles, Characterization and In Vitro Assessment of Antimicrobial, Antioxidant and Cytotoxic Activities.

Asian Pac J Cancer Prev 2019 08 1;20(8):2353-2364. Epub 2019 Aug 1.

Department of Pharmaceutical Sciences, Research Director, GIET School of Pharmacy, Rajahmundry, Andhra Pradesh, India. Email:

Objective: To investigate the biogenic synthesis of silver nanoparticles (AgNPs) using partially purified ethyl acetate extract of Nannochloropsis sp. hexane (EAENH) fraction of microalga. Methods: The green synthesis of AgNPs was confirmed with UV-Vis spectrum which shows the surface plasmon resonance (SPR) at 421 nm. Fourier Transform Infrared Spectra (FTIR) presented the involvement of functional groups like carboxyl groups of fatty acids, tetraterpenoids of xanthophylls, hydroxyl groups of polyphenols, carbonyl and amide linkage of proteins in the AgNP synthesis. Gas Chromatography-Mass Spectrometry analysis (GCMS) revealed that phytochemicals like octadecanoic acid and hexadecanoic acid imply in capping, bioreduction, and stabilization of AgNps. Result: High-resolution Transmission electron microscope (HRTEM), Dynamic light scattering (DLS), X-ray diffraction (XRD) and EDX analysis showed the crystalline form of the AgNPs with Z-average size 57.25 nm. The zeta potential value of -25.7 mV demonstrated the negative surface charge and colloidal stability of AgNPs. The antimicrobial activity of AgNPs displayed effective inhibition zone against selected bacterial and fungal pathogens. In vitro, antioxidant effects were assessed by 1,1-diphenyl-2-picryl-hydrazyl (DPPH), hydrogen peroxide and reducing power assays which revealed excellent scavenging potential for AgNPs than the extracts. The anti-proliferative potential of biofabricated AgNPs and extracts on Human Non-small lung cancer cell line (A549) was assessed using 3–(4,5-dimethylthiazol-2-yl)-2,5- diphenyl-tetrazolium bromide (MTT) assay with IC50 values of 15 μgmL-1 and 175 μgmL-1 respectively. Conclusion: The study reveals that the microalgae-mediated AgNPs possesses potent antimicrobial and antioxidant activity along with the ability to stimulate apoptosis in A-549 cell line.
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http://dx.doi.org/10.31557/APJCP.2019.20.8.2353DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6852812PMC
August 2019

Enzyme Immobilization on Nanomaterials for Biosensor and Biocatalyst in Food and Biomedical Industry.

Curr Pharm Des 2019 ;25(24):2661-2676

College of Food and Dairy Technology, Tamil Nadu Veterinary and Animal Sciences, University, Chennai-600052, Tamil Nadu, India.

Enzymes exhibit a great catalytic activity for several physiological processes. Utilization of immobilized enzymes has a great potential in several food industries due to their excellent functional properties, simple processing and cost effectiveness during the past decades. Though they have several applications, they still exhibit some challenges. To overcome the challenges, nanoparticles with their unique physicochemical properties act as very attractive carriers for enzyme immobilization. The enzyme immobilization method is not only widely used in the food industry but is also a component methodology in the pharmaceutical industry. Compared to the free enzymes, immobilized forms are more robust and resistant to environmental changes. In this method, the mobility of enzymes is artificially restricted to changing their structure and properties. Due to their sensitive nature, the classical immobilization methods are still limited as a result of the reduction of enzyme activity. In order to improve the enzyme activity and their properties, nanomaterials are used as a carrier for enzyme immobilization. Recently, much attention has been directed towards the research on the potentiality of the immobilized enzymes in the food industry. Hence, the present review emphasizes the different types of immobilization methods that is presently used in the food industry and other applications. Various types of nanomaterials such as nanofibers, nanoflowers and magnetic nanoparticles are significantly used as a support material in the immobilization methods. However, several numbers of immobilized enzymes are used in the food industries to improve the processing methods which not only reduce the production cost but also the effluents from the industry.
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http://dx.doi.org/10.2174/1381612825666190712181403DOI Listing
April 2020

Ligand-based pharmacophore mapping and virtual screening for identification of potential discoidin domain receptor 1 inhibitors.

J Biomol Struct Dyn 2020 Jun 8;38(9):2800-2808. Epub 2019 Aug 8.

Department of Biomedical Science, Bharathidasan University, Trichy, India.

AbbreviationsADMEabsorption, distribution, metabolism, and excretionMMGB/SAmolecular mechanics generalized born surface areaIFDinduced fit dockingRTKreceptor tyrosine kinaseNSCLCnon-small-cell lung cancerATPadenosine triphosphateOPLSoptimized potential for liquid stimulationRMSDroot mean square deviationHTVShigh-throughput virtual screeningSPstandard precisionXPextra precisionOPLS-AAoptimized potential for liquid stimulation-all atomMDmolecular simulationMMEmolecular mechanics energiesSGBsurface generalized bornPOPC membrane1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine membranePDBProtein Data BankDDR1discoidin domain receptor 1DDR2discoidin domain receptor 2DDRsdiscoidin domain receptorsECMextracellular matrixTIP4Ptransferable intermolecular potential 4 pointNPTconstant particle number, pressure and temperatureRMSFroot mean square fluctuationCommunicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2019.1640132DOI Listing
June 2020

Mitochondrial genome variations in idiopathic dilated cardiomyopathy.

Mitochondrion 2019 09 22;48:51-59. Epub 2019 Mar 22.

CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India. Electronic address:

Idiopathic dilated cardiomyopathy (DCM) is a structural heart disease with strong genetic background. The aim of this study was to assess the role of mitochondrial DNA (mtDNA) variations and haplogroups in Indian DCM patients. Whole mtDNA analysis of 221 DCM patients revealed 48 novel, 42 disease-associated and 97 private variations. The frequency of reported variations associated with hearing impairment, DEAF, SNHL and LHON are significantly high in DCM patients than controls. Haplogroups H and HV were over represented in DCM than controls. Functional analysis of two private variations (m.8812A>G & m.10320G>A) showed decrease in mitochondrial functions, suggesting the role of mtDNA variations in DCM.
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http://dx.doi.org/10.1016/j.mito.2019.03.003DOI Listing
September 2019

Inhibitory potential of Hydroxychavicol on Ehrlich ascites carcinoma model and interaction on cancer targets.

Nat Prod Res 2020 Jun 23;34(11):1591-1596. Epub 2018 Nov 23.

Department of Biomedical Science, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India.

Hydroxychavicol (HC), a major phenolic derivative isolated from the leaves of is well known for its antibacterial, antifungal and antimutagenic properties. The present study evaluated the antitumor activity of HC against Ehrlich Ascites Carcinoma (EAC) cells in Swiss albino mice and interaction of HC with the receptors involved in the cancer. Hydroxychavicol (200 and 400 mg/kg bw) was orally administered for 21 consecutive days and was effective in inhibiting the tumor growth in ascitic mouse model. HC consistently reduced the tumor volume, viable cell count, lipid peroxidation and elevated the life span of HC treated mice. Besides the hematological profiles, SGOT and SGPT levels reverted back to normal and oxidative stress markers GSH, SOD and CAT also increased in HC treated groups. docking analysis revealed that HC possessed potent antagonist activity against all the cancer targets demonstrating its inhibitory activity.
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http://dx.doi.org/10.1080/14786419.2018.1519819DOI Listing
June 2020

Surface engineered Amphora subtropica frustules using chitosan as a drug delivery platform for anticancer therapy.

Mater Sci Eng C Mater Biol Appl 2019 Jan 6;94:56-64. Epub 2018 Sep 6.

Department of Biomedical Science, School of Basic Medical Sciences, Bharathidasan University, Tiruchirapalli 620 024, Tamil Nadu, India.

Drug delivery using synthetic mesoporous nanomaterials, including porous silicon, has been extensively used to ameliorate the constraints currently experienced with conventional chemotherapy. Owing to the amazing potential, the silica based nanomaterials have been used widely. Nevertheless, synthetic nanomaterial involves high cost, lack of scalability, and the use of toxic substances limits its utilization. These issues can be overcome by the use of nature generated nanoscale materials, such as diatoms would serve as a boon for pharmaceutical industries. In this study we investigate the use of a mesoporous, biodegradable nanomaterial obtained from the natural silica found in the diatom species Amphora subtropica (AMPS) for drug delivery applications. AMPS cultures cleaned and chemically treated to obtain Amphora frustules (exoskeleton) (AF), followed by surface functionalization with chitosan (Chi). Results of our experiments demonstrate high drug loading, strong luminescence, biodegradable and biocompatible nature of the doxorubicin tethered diatom. Further, toxicity studies employing immortalized lung cancer cell line (A549) indicates sustained drug delivery and less toxic compared to the free doxorubicin (DOX), suggesting AF could be an excellent substitute for synthetic nanomaterials used in drug delivery applications.
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http://dx.doi.org/10.1016/j.msec.2018.09.009DOI Listing
January 2019

Somatic Bi-allelic Loss of TSC Genes in Eosinophilic Solid and Cystic Renal Cell Carcinoma.

Eur Urol 2018 10 23;74(4):483-486. Epub 2018 Jun 23.

Department of Pathology, University of Michigan, Ann Arbor, MI, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA; Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, MI, USA; Howard Hughes Medical Institute, Ann Arbor, MI, USA. Electronic address:

Renal cell carcinomas (RCC) with overlapping histomorphologic features poses diagnostic challenges. This is exemplified in RCCs with eosinophilic cytoplasm that include eosinophilic solid and cystic RCC (ESC RCC), RCCs in germline aberrations of tuberous sclerosis complex (TSC) genes mutated (TSC RCC) individuals, and other RCC subtypes. We used next-generation sequencing (NGS) technology to molecularly profile seven ESC RCC tumors. Mutational and copy number analysis of NGS data revealed mutually exclusively somatic bi-allelic loss of TSC1 or TSC2 genes-both negative regulators of the mammalian target of rapamycin (mTOR) pathway in 85% (6/7) of evaluated cases. Thus, lack of germline TSC aberration in matched non-neoplastic renal parenchyma distinguishes ESC RCC from TSC RCC. Immunohistochemistry data shows mTOR pathway activation in all tumors, thus supporting a pathognomonic role for TSC aberrations in ESC RCC. Our study clarifies the molecular identity of ESC RCC, provides basis for the revision of current RCC classification, and may guide future therapeutic strategies.

Patient Summary: Molecular characterization of eosinophilic solid and cystic renal cell carcinomas (ESC RCC) revealed recurrent and mutually exclusive somatic homozygous loss of tuberous sclerosis complex family genes. This observation provides greater insight into the unique biology of this novel type of tumor and potentially expands the therapeutic options for ESC RCC patients.
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http://dx.doi.org/10.1016/j.eururo.2018.06.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6390848PMC
October 2018

Gold and Silver Nanoparticles Biomimetically Synthesized Using Date Palm Pollen Extract-Induce Apoptosis and Regulate p53 and Bcl-2 Expression in Human Breast Adenocarcinoma Cells.

Biol Trace Elem Res 2018 Nov 18;186(1):122-134. Epub 2018 Mar 18.

Holistic International Testing Services FZ-LLC, G04-A1, Ground Floor, Dubiotech Laboratory Building, P.O. Box 500767, Dubai, UAE.

Recently, several attempts have been made to use the phytopharmaceuticals from plant extracts as reducing, capping and stabilizing agents for the biomimetic synthesis of various metal nanoparticles conjugated to the phytopharmaceuticals. These biogenic metal nanoparticles are non-toxic and can be used as contrast agents, drug delivery vehicles and photothermal agents for cancer therapy. Herein, we report the synthesis of both silver and gold nanoparticles using the pollen extract of Phoenix dactylifera (Date Palm), characterization using UV-visible spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, quantitation of phytochemicals capping the nanoparticles using Folin - Ciocalteu's method, cytotoxicity studies on MCF-7 breast cancer cells, cancer cell death analysis using fluorescent microscopy, and modulation of expression of the pro-apoptotic p53 and anti-apoptotic Bcl-2 proteins. The biosynthesis resulted in stable and poly-dispersed silver nanoparticles and gold nanoparticles, exhibiting strong and broad surface plasmon absorption peaks. The elemental analysis confirmed the presence of gold and silver of high purity and also the organic moieties from the plant extract acting as capping and stabilizing agents. The biogenic nanoparticles also exhibited dose-dependent cytotoxicity on MCF-7 cells and showed signs of apoptotic cell death. Immunoassays revealed the upregulation of the pro-apoptotic protein p53 and down-regulation of the anti-apoptotic protein Bcl-2 after the nanoparticle treatment.
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http://dx.doi.org/10.1007/s12011-018-1287-0DOI Listing
November 2018

Hypoxia stimulates microenvironment in human embryonic stem cell through inflammatory signalling: An integrative analysis.

Biochem Biophys Res Commun 2018 04 28;498(3):437-444. Epub 2018 Feb 28.

Cancer Genetics and Nanomedicine Laboratory, Department of Biomedical Science, School of Basic Medical Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India. Electronic address:

Despite, several lines of evidence suggesting the possible role of hypoxia in stem cell development and differentiation its significance in conferring the stemness and pluripotency remains elusive. In the present study we sought to delineate the candidate genes and molecular pathways imposed during hypoxic microenvironment and its physiological relevance in tipping the balance between the niche and cellular differentiation. Integrated meta-analysis was performed between the hypoxia exposed and normal human embryonic stem cells, employing three transcriptomic cohorts (GSE35819, GSE9510 and GSE37761) retrieved from Gene expression omnibus (GEO) database. Results reveal that a total number of 12 genes were consistently differentially expressed (6up regulated and 6 down regulated) with FDR <0.05 and fold change >1.5. The Gene Ontology (GO) functions and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis was performed using DAVID. The GO analysis showed DEG significantly enriched in terms of Cellular process (GO:0009987), protein binding (GO:0005515) and cell part (GO:0044464). KEGG analysis indicated participation of genes associated with circadian rthyum regulation and PPAR signalling pathway. Further, gene-set signature (MsigDB) enrichment analysis showed positive regulation with inflammatory signals and negative association with PPAR and p53 pathway. Protein-protein network of gene modules suggests significant hub proteins viz. CTTNB1 (Degree = 18), IL8 (Degree = 15), NFKB1 (Degree = 15) and RELA (Degree = 15) in the PPI network. MCODE algorithm was used for subnetworks of the PPI network. Our integrative analysis documents the potential candidate genes which serves distinct roles influencing metabolic shift and induce inflammatory effectors contributing to hypoxic mediated stem cell niche.
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http://dx.doi.org/10.1016/j.bbrc.2018.02.194DOI Listing
April 2018

Anticancer potential of ZnO nanoparticle-ferulic acid conjugate on Huh-7 and HepG2 cells and diethyl nitrosamine induced hepatocellular cancer on Wistar albino rat.

Nanomedicine 2018 02 21;14(2):415-428. Epub 2017 Nov 21.

Department of Biochemistry and Molecular Biology, Pondicherry University, Puducherry, India. Electronic address:

Drawbacks and limitations of recently available therapies to hepatocellular cancer (HCC) devoted the scientist to focus on emerging new strategies. ZnO nanoparticles (ZnONPs) based chemotherapeutics has been emanating as a promising approach to maximize therapeutic synergy facilitating the discovery of novel multitargeted combinations. In the present study we conjugated ZnONPs with ferulic acid (ZnONPs-FAC) characterized by computational, spectroscopic and microscopic techniques. In vitro anticancer potential has been evaluated by assessing cell viability, morphology, ROS generation, mitochondrial membrane permeability, comet assay, immunofluorescent staining of 8-OHdG, Ki67 and γ-H2AX, cell cycle analysis and western blot analysis and in vivo anticancer potential against DEN induced HCC was analyzed by histopathological and immunohistochemical methods. The results revealed that ZnONPs-FAC induces cell death through apoptosis and can suppress the DEN-induced HCC. Our study documents therapeutic potential of nanoparticle conjugated with phytochemicals, suggesting a new platform for combinatorial chemotherapy.
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http://dx.doi.org/10.1016/j.nano.2017.11.003DOI Listing
February 2018

Biallelic Alteration and Dysregulation of the Hippo Pathway in Mucinous Tubular and Spindle Cell Carcinoma of the Kidney.

Cancer Discov 2016 11 7;6(11):1258-1266. Epub 2016 Sep 7.

Department of Pathology, University of Michigan Health System, Ann Arbor, Michigan.

Mucinous tubular and spindle cell carcinoma (MTSCC) is a relatively rare subtype of renal cell carcinoma (RCC) with distinctive morphologic and cytogenetic features. Here, we carry out whole-exome and transcriptome sequencing of a multi-institutional cohort of MTSCC (n = 22). We demonstrate the presence of either biallelic loss of Hippo pathway tumor suppressor genes (TSG) and/or evidence of alteration of Hippo pathway genes in 85% of samples. PTPN14 (31%) and NF2 (22%) were the most commonly implicated Hippo pathway genes, whereas other genes such as SAV1 and HIPK2 were also involved in a mutually exclusive fashion. Mutations in the context of recurrent chromosomal losses amounted to biallelic alterations in these TSGs. As a readout of Hippo pathway inactivation, a majority of cases (90%) exhibited increased nuclear YAP1 protein expression. Taken together, nearly all cases of MTSCC exhibit some evidence of Hippo pathway dysregulation.

Significance: MTSCC is a rare and relatively recently described subtype of RCC. Next-generation sequencing of a multi-institutional MTSCC cohort revealed recurrent chromosomal losses and somatic mutations in the Hippo signaling pathway genes leading to potential YAP1 activation. In virtually all cases of MTSCC, there was evidence of Hippo pathway dysregulation, suggesting a common mechanistic basis for this disease. Cancer Discov; 6(11); 1258-66. ©2016 AACR.This article is highlighted in the In This Issue feature, p. 1197.
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http://dx.doi.org/10.1158/2159-8290.CD-16-0267DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5096979PMC
November 2016

Oxystressed tumor microenvironment potentiates epithelial to mesenchymal transition and alters cellular bioenergetics towards cancer progression.

Tumour Biol 2016 Oct 26;37(10):13307-13322. Epub 2016 Jul 26.

Cancer Genetics and Nanomedicine Laboratory, Department of Biomedical Science, School of Basic Medical Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India.

During tumorigenesis, cancer cells generate complex, unresolved interactions with the surrounding oxystressed cellular milieu called tumor microenvironment (TM) that favors spread of cancer to other body parts. This dissemination of cancer cells from the primary tumor site is the main clinical challenge in cancer treatment. In addition, the significance of enhanced oxidative stress in TM during cancer progression still remains elusive. Thus, the present study was performed to investigate the molecular and cytoskeletal alterations in breast cancer cells associated with oxystressed TM that potentiates metastasis. Our results showed that depending on the extent of oxidative stress in TM, cancer cells exhibited enhanced migration and survival with reduction of chemosensitivity. Corresponding ultrastructural analysis showed radical cytoskeletal modifications that reorganize cell-cell interactions fostering transition of epithelial cells to mesenchymal morphology (EMT) marking metastasis, which was reversed upon antioxidant treatment. Decreased E-cadherin and increased vimentin, Twist1/2 expression corroborated the initiation of EMT in oxystressed TM-influenced cells. Further evaluation of cellular energetics demonstrated significant metabolic reprogramming with inclination towards glucose or external glutamine from TM as energy source depending on the breast cancer cell type. These observations prove the elemental role of oxystressed TM in cancer progression, initiating EMT and metabolic reprogramming. Further cell-type specific metabolomic analysis would unravel the alternate mechanisms in cancer progression for effective therapeutic intervention. Graphical abstract Schematic representation of the study and proposed mechanism of oxystressed TM influenced cancer progression. Cancer cells exhibit a close association with tumor microenvironment (TM), and oxystressed TM enhances cancer cell migration and survival and reduces chemosensitivity. Oxystressed TM induces dynamic cytomorphological variations, alterations in expression patterns of adhesion markers, redox homeostasis, and metabolic reprogramming that supports epithelial to mesenchymal transition and cancer progression.
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http://dx.doi.org/10.1007/s13277-016-5224-6DOI Listing
October 2016

Chitosan Tethered Colloidal Gold Nanospheres for Drug Delivery Applications.

J Nanosci Nanotechnol 2016 Jan;16(1):229-41

Gold Nanospheres (AuNS) have been widely explored as an emerging system for various biomedical applications including drug delivery, bioimaging and photomedicine. However, method of synthesizing nanoparticles and its toxicity including bioaccumulation has been a problem of concern. In the present study, we explored the appropriateness of 12.0 ±1.99 nm chitosan reduced AuNS in vivo models with respect to its bioavailability and toxicity against various concentrations (2.5-7.5 mg/kg). Administration of AuNS did not show any signs of morbidity. Inductively coupled plasma optical emission spectrometry (ICP-OES) analysis of blood (0.156 ± 0.154), urine (0.084 ± 0.08) and tissues indicates gradual dissipation and obligatory clearance within 24 h time interval. Nevertheless, pres- ence of AuNS in blood after 24 h confirms the bioavailability of AuNS demonstrating the evidence for no immune clearance and efficient tissue uptake. Further, brain shows the lowest quantity of injected AuNS. From this result, we determine this chitosan monolayer protected AuNS could cross the blood brain barrier and enter to the neural tissues. Interestingly there was no evidence of toxicity in any of the organs. In conclusion, our data suggest that AuNS injected though tail vain were easily taken up by tissues and does not produce sub-acute physiological damage even at high concentrations tested, supporting chitosan reduced AuNS as biocompatible, nontoxic nanoconjugates for targeted drug delivery and other biomedical applications.
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http://dx.doi.org/10.1166/jnn.2016.10672DOI Listing
January 2016

Impact of Anthocyanidins on Mitoxantrone-Induced Cytotoxicity and Genotoxicity: An In Vitro and In Vivo Analysis.

Integr Cancer Ther 2016 12 4;15(4):525-534. Epub 2016 May 4.

Bharathidasan University, Tiruchirappalli, Tamil Nadu, India

Hypothesis Anthocyanins possess well-known biological effects and suppress DNA damage induced by therapeutic topoisomerase poisons. Our study focusses on the modulatory effects of anthocyanidins-malvidin (MAL) and pelargonidin (PEL)-on topoisomerase II poison mitoxantrone (MXT)-induced cytotoxicity and genotoxicity in in vitro and in vivo conditions. Study design HepG2 cells were treated with MXT (1-10 µM), MAL (10-100 µM,) and PEL (5-640 µM) to determine cell viability. Further, experiments on cytotoxicity and apoptosis induction by single agents or combinations were performed. In vitro and in vivo antigenotoxic effect of MAL/PEL against MXT was evaluated in human lymphocytes and mouse bone marrow cells. Methods Cytotoxicity of test agents and apoptosis induction in HepG2 cells was assessed by MTT assay, trypan blue dye exclusion assay and Hoechst 33258 staining. Antigenotoxic effects of MAL/PEL against MXT were assessed in co-treated human lymphocytes and bone marrow from mice that received MXT intraperitoneally 30 minutes post MAL/PEL oral administration Results Dose-dependent cytotoxicity was observed with all 3 test agents in HepG2 cells. Highest test concentration of 100 µM MAL, 640 µM PEL, and 10 µM MXT decreased HepG2 cell viability by 80%, 30%, and 90%, respectively. The combination of 1 µM MXT + 80 µM MAL reduced cell viability better than single agents. MAL/PEL treatment significantly reduced MXT-induced genotoxicity in human lymphocytes and micronuclei formation in mice. Conclusion Combination of MAL/PEL with lower doses of MXT, especially MAL+MXT increases the cytotoxicity in cancer cells. In addition, MXT treatment with MAL/PEL reduced MXT-induced genotoxicity and protected normal cells during chemotherapy.
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http://dx.doi.org/10.1177/1534735416628344DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5739156PMC
December 2016

Low-dose chemotherapeutic drugs induce reactive oxygen species and initiate apoptosis-mediated genomic instability.

Toxicol Res (Camb) 2016 Mar 7;5(2):547-556. Epub 2016 Jan 7.

Cancer Genetics and Nanomedicine Laboratory , Department of Biomedical Science , School of Basic Medical Sciences , Bharathidasan University , Tiruchirappalli 620024 , Tamilnadu , India . Email: ; ; Tel: +91-8056589893.

Prolonged cancer cell survival, acquiring drug resistance, and secondary cancer development despite chemotherapy are the major challenges during cancer treatment, whose underlying mechanism still remains elusive. In this study, low-doses of chemotherapeutic drugs (LDCD) - doxorubicin (DOX), etoposide (ETOP), and busulfan (BUS) were used to ascertain the effect of residual concentrations of drugs on breast cancer cells. Our results showed that exposure to LDCD caused significant induction of ROS, early signs of apoptosis and accumulation of cells in S and G-M phases of the cell cycle in MCF-7 and MDA-MB-231 cell lines. Under drug-free recovery conditions, a decrease in the number of apoptotic cells and an increase in the number of colonies formed were observed. Analysis of the molecular mechanism showed lower expression of cleaved products of caspase 3, 9, PARP and occurrence of DNA strand breaks in recovered cells compared to LDCD-treated cells, suggesting incomplete cell death activation and survival of cells with genomic damage after therapeutic insult. Thus, LDCD induces defective apoptosis in cancer cells allowing a small population of cells to escape from cell cycle check points and survive with accumulated genetic damage that could eventually result in secondary cancers that warrants further studies for better therapeutic strategies.
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http://dx.doi.org/10.1039/c5tx00391aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6062221PMC
March 2016

Nomadic genetic elements contribute to oncogenic translocations: Implications in carcinogenesis.

Crit Rev Oncol Hematol 2016 Feb 31;98:81-93. Epub 2015 Oct 31.

Cancer Genetics and Nanomedicine Laboratory, Department of Biomedical Science, School of Basic Medical Sciences, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India. Electronic address:

Chromosomal translocations as molecular signatures have been reported in various malignancies but, the mechanism behind which is largely unknown. Swapping of chromosomal fragments occurs by induction of double strand breaks (DSBs), most of which were initially assumed de novo. However, decoding of human genome proved that transposable elements (TE) might have profound influence on genome integrity. TEs are highly conserved mobile genetic elements that generate DSBs, subsequently resulting in large chromosomal rearrangements. Previously TE insertions were thought to be harmless, but recently gains attention due to the origin of spectrum of post-insertional genomic alterations and subsequent transcriptional alterations leading to development of deleterious effects mainly carcinogenesis. Though the existing knowledge on the cancer-associated TE dynamics is very primitive, exploration of underlying mechanism promises better therapeutic strategies for cancer. Thus, this review focuses on the prevalence of TE in the genome, associated genomic instability upon transposition activation and impact on tumorigenesis.
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http://dx.doi.org/10.1016/j.critrevonc.2015.10.012DOI Listing
February 2016

Doxorubicin loaded polymeric gold nanoparticles targeted to human folate receptor upon laser photothermal therapy potentiates chemotherapy in breast cancer cell lines.

J Photochem Photobiol B 2015 Aug 1;149:116-28. Epub 2015 Jun 1.

Holistic International Testing Services FZ-LLC, Unit#G04-A1, Ground Floor, Dubiotech Laboratory Building, P.O. Box 500767, Dubai, United Arab Emirates. Electronic address:

The current research focuses on the application of folate conjugated and doxorubicin loaded polymeric gold nanoparticles (GNPs) for the targeted treatment of folate receptor overexpressing breast cancers, augmented by adjunctive laser photothermal therapy. Herein, GNPs surface modified with folate, drug doxorubicin and polyethylene glycol were engineered and were used as vehicles for folate receptor targeted delivery of doxorubicin into cancer cells. Subsequently, the GNPs were photo-excited using laser light for mediating hyperthermia in the cancer cells. In vitro studies were performed to validate the efficacy of the combined modality of folate conjugated and doxorubicin loaded polymeric GNP mediated chemotherapy followed by photothermal therapy in comparison to treatment with free drug; and the combination modality showed better therapeutic efficacy than that of plain doxorubicin treatment in MDA-MB-231 breast cancer cells that express increased levels of surface folate receptors when compared to MCF-7 breast cancer cells that express low levels of folate receptor. The mechanism of cell death was investigated using fluorescent microscopy. Immunoassays showed the up-regulation of the pro-apoptotic protein p53 and down-regulation of the anti-apoptotic protein Bcl-2. Collectively, these results suggest that the folate tagged doxorubicin loaded GNPs are an attractive platform for targeted delivery of doxorubicin and are agents suitable for photothermal cancer therapy.
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http://dx.doi.org/10.1016/j.jphotobiol.2015.05.008DOI Listing
August 2015

Near infra-red laser mediated photothermal and antitumor efficacy of doxorubicin conjugated gold nanorods with reduced cardiotoxicity in swiss albino mice.

Nanomedicine 2015 Aug 14;11(6):1435-44. Epub 2015 Apr 14.

Cancer Genetics and Nanomedicine Laboratory, Department of Biomedical Science, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India. Electronic address:

Unlabelled: Development of a multifunctional drug delivering system without side effects and compromising its therapeutic efficacy is a major concern in anticancer research. Recently, we have developed and demonstrated doxorubicin conjugated gold nanorod ([email protected]) as a sustained drug delivery vehicle. Here, we investigate the biodistribution, antitumor and photothermal efficacy of [email protected] along with its potential impact on cardiotoxicity in in vivo. The studies revealed that the accumulation of Free DOX in myocardium was 4-fold reduced in [email protected] animals, which further minimizes its cardiotoxicity by decreasing cardiac injury via preservation of cardiac markers. Further, [email protected] exhibits effective antitumor efficacy against Dalton lymphoma ascites (DLA) as evidenced by cell cycle analysis, apoptotic signals and reduced tumor volume and weight. In addition, [email protected] exhibits higher photothermal response and dominates DLA growth upon 0.1 W/cm(2) laser irradiation. In conclusion, multifunctional [email protected] with improved therapeutic index and reduced cardiotoxicity represents a promising candidate for cancer treatment.

From The Clinical Editor: Doxorubicin is a widely used agent for cancer therapy. However, the side effects are still significant, despite the development of liposomal formulation. In this study, the authors investigated the use of doxorubicin conjugated gold nanorods ([email protected]) in terms of biodistribution, antitumor activity and systemic side effects. The much reduced cardiotoxicity of the new delivery system should provide an improved agent for future clinical use.
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http://dx.doi.org/10.1016/j.nano.2015.03.012DOI Listing
August 2015

Sighting of tankyrase inhibitors by structure- and ligand-based screening and in vitro approach.

Mol Biosyst 2014 Oct;10(10):2699-712

Department of Bioinformatics, Science Block, Alagappa University, Karaikudi - 630 004, Tamil Nadu, India.

Tankyrase 1 and 2 (TNKS) are promising and attractive therapeutic targets in anticancer drug development. Herein, we report the findings of structure- and ligand-based virtual screening for novel TNKS1 inhibitors using iterative rounds of in silico studies and subsequent biological evaluation methods. Upon screening of three compound databases, a final set of five molecules were selected for experimental validation. In order to prove our in silico findings, tankyrase activity was assessed by a calorimetric assay with the five identified lead molecules. Out of five, only C1 (7309981) showed significant inhibition of TNKS1 enzyme. Furthermore, the toxicity of the selected 5 compounds was measured using cytotoxicity experiments and inhibition of cell growth, and it was more pronounced in C1, followed by C5 and C3 (7309981 > 7245236 > 7275738). The morphological assessment, DNA damage and chromatin condensation and fragmentation results also confirmed that C1 has enhanced activity against MCF-7 cells.
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http://dx.doi.org/10.1039/c4mb00309hDOI Listing
October 2014

Unravelling the distinct strains of Tharu ancestry.

Eur J Hum Genet 2014 Dec 26;22(12):1404-12. Epub 2014 Mar 26.

Evolutionary Biology Group, Estonian Biocentre, Tartu, Estonia.

The northern region of the Indian subcontinent is a vast landscape interlaced by diverse ecologies, for example, the Gangetic Plain and the Himalayas. A great number of ethnic groups are found there, displaying a multitude of languages and cultures. The Tharu is one of the largest and most linguistically diverse of such groups, scattered across the Tarai region of Nepal and bordering Indian states. Their origins are uncertain. Hypotheses have been advanced postulating shared ancestry with Austroasiatic, or Tibeto-Burman-speaking populations as well as aboriginal roots in the Tarai. Several Tharu groups speak a variety of Indo-Aryan languages, but have traditionally been described by ethnographers as representing East Asian phenotype. Their ancestry and intra-population diversity has previously been tested only for haploid (mitochondrial DNA and Y-chromosome) markers in a small portion of the population. This study presents the first systematic genetic survey of the Tharu from both Nepal and two Indian states of Uttarakhand and Uttar Pradesh, using genome-wide SNPs and haploid markers. We show that the Tharu have dual genetic ancestry as up to one-half of their gene pool is of East Asian origin. Within the South Asian proportion of the Tharu genetic ancestry, we see vestiges of their common origin in the north of the South Asian Subcontinent manifested by mitochondrial DNA haplogroup M43.
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http://dx.doi.org/10.1038/ejhg.2014.36DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4231405PMC
December 2014

Mitochondrial DNA variations associated with hypertrophic cardiomyopathy.

Mitochondrion 2014 May 9;16:65-72. Epub 2013 Nov 9.

CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India. Electronic address:

Hypertrophic cardiomyopathy (HCM) is a primary disorder, characterized by unexplained hypertrophy of the left ventricle that frequently involved in the inter-ventricular septum. Mitochondrial DNA (mtDNA) mutations and haplogroups have been found to be associated with several diseases. Therefore, in the present study, we have sequenced the complete mtDNA of 114 clinically well-characterized HCM patients to look for the role of mtDNA variations and haplogroups in HCM phenotype among Indian patients. Complete mtDNA analysis revealed 28 novel variations, 25 disease-associated and 50 private mutations. We found 13 (11.40%) HCM patients having novel non-synonymous and/or MT-tRNA variations, of which two (m.4797C>M and m.8728T>Y) were in heteroplasmic condition. In silico prediction showed that a few mutations are pathogenic, which may affect the energy production in the heart. Unlike some of the other studies, we did not find association of mitochondrial haplogroup with HCM.
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http://dx.doi.org/10.1016/j.mito.2013.10.006DOI Listing
May 2014

Polymer-cobalt(III) complexes: structural analysis of metal chelates on DNA interaction and comparative cytotoxic activity.

J Biomol Struct Dyn 2014 20;32(11):1876-88. Epub 2013 Sep 20.

a School of Chemistry, Bharathidasan University , Tiruchirappalli , Tamil Nadu , 620 024 , India .

A new series of pendant-type polymer-cobalt(III) complexes, [Co(LL)2(BPEI)Cl](2+), (where BPEI = branched polyethyleneimine, LL = dipyrido[3,2-a:2',3'-c](6,7,8,9-tetrahydro)phenazine (dpqc), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) and imidazo[4,5-f]1,10-phenanthroline (ip)) each with three different degrees of coordination have been synthesized and characterized. Studies to know the mode and strength of interaction between these polymer-metal complexes and calf thymus DNA have been performed by UV-Visible absorption and emission techniques. Among these series, each polymer metal complex having higher binding strength with DNA has been selected to test against human cancer/normal cell lines. On the basis of these spectral studies, it is proposed that our polymer-metal complexes bind with DNA mainly through intercalation along with some electrostatic binding. The order of binding strength for the complexes with ligand, dpqc > dpq > ip. The analysis of the results suggests that polymer-cobalt(III) complexes with higher degree of coordination effectively binds with DNA due to the presence of large number of positively charged cobalt(III) chelates in the polymer chain which cooperatively act to increase the overall binding strength. These polymer-cobalt(III) complexes with hydrophobic ligands around the cobalt(III) metal centre favour the base stacking interactions via intercalation. All the complexes show very good anticancer activities and increasing of binding strength results in higher inhibition value. The polymer-cobalt(III) complex with dpqc ligand possess two fold increased anticancer activity when compared to complexes with other ligands against MCF-7 cells. Besides, the complexes were insensitive towards the growth of normal cells (HEK-293) at the IC50 concentration.
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http://dx.doi.org/10.1080/07391102.2013.836460DOI Listing
May 2015

Comparative bioactive studies between wild plant and callus culture of Tephrosia tinctoria pers.

Appl Biochem Biotechnol 2013 Dec 12;171(8):2105-20. Epub 2013 Sep 12.

Department of Biotechnology, Bharathidasan Institute of Technology, Anna University, Tiruchirappalli, 620 024, Tamil Nadu, India.

Tephrosia tinctoria, a perennial under shrub of Fabaceae family, is endemic to Western Ghats. In this study, friable whitish yellow callus was developed after 45 days using Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid (2.0 mg/l) + 6-benzylaminopurine (0.5 mg/l) in various explants of T. tinctoria. The ethyl acetate extracts of leaf (LE), stem (SE), and root (RE) were compared with leaf (LCE), stem (SCE), and root (RCE) derived callus, for antioxidant and antiproliferative activities. The SE possessed the highest phenolic and flavonoid content among all the extracts tested and showed a significant antioxidant assays. The study of anticancer activity on human hepatocellular carcinoma (HepG2) cell line revealed that the callus extracts especially RCE possessed significant inhibition of cell growth (IC50 20 μg/ml) at 72 h treatment period on analysis with MTT assay. The apoptotic cell death was observed through DNA fragmentation analysis in HepG2 cells treated with the T. tinctoria extracts. The gas chromatography-mass spectrometry finger printing profile showed that more than 60 % percentage of metabolites are similar in both SE and SCE. The higher percentage area of antioxidant compound (stigmast-4-en-3-one) was observed in SE (2.01 %) and higher percentage area of anticancer compound (phenol, 2,4-bis(1,1-dimethylethyl)) in SCE (0.91 %). In addition to that, callus extracts contain squalene, which is used for target deliver and also used as anticancer drug. Thus, the present study revealed that the T. tinctoria has potent antioxidant and antiproliferative activity and the callus culture can be used for the production of the bioactive compounds due to the endemic nature of this plant.
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http://dx.doi.org/10.1007/s12010-013-0444-3DOI Listing
December 2013

Doxorubicin conjugated gold nanorods: a sustained drug delivery carrier for improved anticancer therapy.

J Mater Chem B 2013 Feb 11;1(7):1010-1018. Epub 2012 Dec 11.

Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli-620024, Tamil Nadu, India.

Theranostic nanoparticles with multifunctional ability have been emerging as a new platform for biomedical applications such as imaging, sensing and drug delivery. Despite gold nanorods (Au NRs) being an excellent nanosource with multifunctional versatility, they have certain limitations in biomedical applications, which include surfactant toxicity, biological stability and controlled drug release kinetics. Herein, we have developed Au NR-doxorubicin conjugates ([email protected] NR) with improved drug loading efficiency (55 ± 6%) and minimum CTAB toxicity, by employing Au NRs (4.4 ± 0.5 aspect ratio) coated with poly(sodium 4-styrenesulfonate) (PSS). [email protected] NR conjugates exhibited higher biological stability with sustained drug release kinetics at pH 5. The binding events of DOX molecules onto the PSS coated gold nanorods (PSS-Au NRs) were monitored through fluorescence quenching and the longitudinal surface plasmon resonance signals. Furthermore the anti-cancer potential and apoptosis inducing efficiency of [email protected] NR conjugates in MCF-7 cells revealed higher therapeutic efficiency than free DOX, as corroborated through morphological assessment and in vitro cytotoxicity assay. In addition, [email protected] NR conjugates showed efficient cellular entry and uniform intracellular distribution, suggesting the augmenting effect of chemotherapeutic drugs by Au NRs. Thus [email protected] NR conjugates demonstrate significant therapeutic potential, suggesting their potential in anticancer therapy.
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http://dx.doi.org/10.1039/c2tb00078dDOI Listing
February 2013

Micrococcus luteus mediated dual mode synthesis of gold nanoparticles: involvement of extracellular α-amylase and cell wall teichuronic acid.

Colloids Surf B Biointerfaces 2013 Mar 9;103:517-22. Epub 2012 Nov 9.

Cancer Genetics & Nanomedicine Laboratory, Department of Biomedical Science, School of Basic Medical Sciences, Bharathidasan University, Tiruchirappalli 620024, Tamilnadu, India.

In the present study we have utilized the bioreductive potential of Micrococcus luteus for the synthesis of gold nanoparticles. Biochemical and physiological analysis indicate that the biosynthesized GNPs were achieved by dual mode, involving extracellular α-amylase and cell wall teichuronic acid (TUA) of M. luteus. The biosynthetic potential of both α-amylase and TUA, after isolation from bacterium, was examined. Under optimum conditions, these biomolecules reduces Au(3+) into Au(0) and the resulting GNPs were found to be stable for 1 month. The synthesized GNPs were characterized by UV-VIS spectrometry, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS). Results demonstrated that the synthesized GNPs were found to be monodispersive and spherical in shape with an average size of ∼6 nm and ∼50 nm for α-amylase and teichuronic acid, respectively. These findings suggest that M. luteus can be exploited as a potential biosource for the eco-friendly synthesis of gold nanoparticles.
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http://dx.doi.org/10.1016/j.colsurfb.2012.10.051DOI Listing
March 2013
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