Publications by authors named "Francesca Orso"

40 Publications

Macrophage miR-210 induction and metabolic reprogramming in response to pathogen interaction boost life-threatening inflammation.

Sci Adv 2021 May 7;7(19). Epub 2021 May 7.

Laboratory of Tumor Inflammation and Angiogenesis, CCB, VIB, Leuven, Belgium.

Unbalanced immune responses to pathogens can be life-threatening although the underlying regulatory mechanisms remain unknown. Here, we show a hypoxia-inducible factor 1α-dependent microRNA (miR)-210 up-regulation in monocytes and macrophages upon pathogen interaction. MiR-210 knockout in the hematopoietic lineage or in monocytes/macrophages mitigated the symptoms of endotoxemia, bacteremia, sepsis, and parasitosis, limiting the cytokine storm, organ damage/dysfunction, pathogen spreading, and lethality. Similarly, pharmacologic miR-210 inhibition improved the survival of septic mice. Mechanistically, miR-210 induction in activated macrophages supported a switch toward a proinflammatory state by lessening mitochondria respiration in favor of glycolysis, partly achieved by downmodulating the iron-sulfur cluster assembly enzyme ISCU. In humans, augmented miR-210 levels in circulating monocytes correlated with the incidence of sepsis, while serum levels of monocyte/macrophage-derived miR-210 were associated with sepsis mortality. Together, our data identify miR-210 as a fine-tuning regulator of macrophage metabolism and inflammatory responses, suggesting miR-210-based therapeutic and diagnostic strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1126/sciadv.abf0466DOI Listing
May 2021

ESDN inhibits melanoma progression by blocking E-selectin expression in endothelial cells via STAT3.

Cancer Lett 2021 Jul 13;510:13-23. Epub 2021 Apr 13.

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy; Dept. Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy. Electronic address:

An interactive crosstalk between tumor and stroma cells is essential for metastatic melanoma progression. We evidenced that ESDN/DCBLD2/CLCP1 plays a crucial role in endothelial cells during the spread of melanoma. Precisely, increased extravasation and metastasis formation were revealed in ESDN-null mice injected with melanoma cells, even if the primary tumor growth, vessel permeability, and angiogenesis were not enhanced. Interestingly, improved adhesion of melanoma cells to ESDN-depleted endothelial cells was observed, due to the presence of higher levels of E-selectin transcripts/proteins in ESDN-defective cells. In accordance with these results, anticorrelation was observed between ESDN and E-selectin in human endothelial cells. Most importantly, our data revealed that cimetidine, an E-selectin inhibitor, was able to block cell adhesion, extravasation, and metastasis formation in ESDN-null mice, underlying a major role of ESDN in E-selectin transcription upregulation, which according to our data, may presumably be linked to STAT3. Based on our results, we propose a protective role for ESDN during the spread of melanoma and reveal its therapeutic potential.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.canlet.2021.04.005DOI Listing
July 2021

MicroRNA-Mediated Metabolic Shaping of the Tumor Microenvironment.

Cancers (Basel) 2021 Jan 3;13(1). Epub 2021 Jan 3.

Molecular Biotechnology Center (MBC), University of Torino, 10126 Torino, Italy.

The metabolism of cancer cells is generally very different from what is found in normal counterparts. However, in a tumor mass, the continuous crosstalk and competition for nutrients and oxygen among different cells lead to metabolic alterations, not only in cancer cells, but also in the different stromal and immune cells of the tumor microenvironment (TME), which are highly relevant for tumor progression. MicroRNAs (miRs) are small non-coding RNAs that silence their mRNA targets post-transcriptionally and are involved in numerous physiological cell functions as well as in the adaptation to stress situations. Importantly, miRs can also be released via extracellular vesicles (EVs) and, consequently, take part in the bidirectional communication between tumor and surrounding cells under stress conditions. Certain miRs are abundantly expressed in stromal and immune cells where they can regulate various metabolic pathways by directly suppressing enzymes or transporters as well as by controlling important regulators (such as transcription factors) of metabolic processes. In this review, we discuss how miRs can induce metabolic reprogramming in stromal (fibroblasts and adipocytes) and immune (macrophages and T cells) cells and, in turn, how the biology of the different cells present in the TME is able to change. Finally, we debate the rebound of miR-dependent metabolic alterations on tumor progression and their implications for cancer management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cancers13010127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7795884PMC
January 2021

Axl-148b chimeric aptamers inhibit breast cancer and melanoma progression.

Int J Biol Sci 2020 10;16(7):1238-1251. Epub 2020 Feb 10.

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy.

microRNAs (miRNAs) are small non-coding RNAs acting as negative regulators of gene expression and involved in tumor progression. We recently showed that inhibition of the pro-metastatic miR-214 and simultaneous overexpression of its downstream player, the anti-metastatic miR-148b, strongly reduced metastasis formation. To explore the therapeutic potential of miR-148b, we generated a conjugated molecule aimed to target miR-148b expression selectively to tumor cells. Precisely, we linked miR-148b to GL21.T, an aptamer able to specifically bind to AXL, an oncogenic tyrosine kinase receptor highly expressed on cancer cells. Axl-148b conjugate was able to inhibit migration and invasion of AXL-positive, but not AXL-negative, cancer cells, demonstrating high efficacy and selectivity . In parallel, expression of ALCAM and ITGA5, two miR-148b direct targets, was reduced. More importantly, axl-148b chimeric aptamers were able to inhibit formation and growth of 3D-mammospheres, to induce necrosis and apoptosis of treated xenotransplants, as well as to block breast cancer and melanoma dissemination and metastatization in mice. Relevantly, axl aptamer acted as specific delivery tool for miR-148b, but it also actively contributed to inhibit metastasis formation, together with miR-148b. In conclusion, our data show that axl-148b conjugate is able to inhibit tumor progression in an axl- and miR-148b-dependent manner, suggesting its potential development as therapeutic molecule.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7150/ijbs.39768DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7053324PMC
February 2020

The role of melatonin on miRNAs modulation in triple-negative breast cancer cells.

PLoS One 2020 3;15(2):e0228062. Epub 2020 Feb 3.

Department of Biology, Universidade Estadual Paulista "Júlio de Mesquita Filho", São José do Rio Preto, São Paulo, Brazil.

Melatonin, a hormone secreted by pineal gland, exerts antimetastatic effects by reducing tumor cell proliferation, migration and invasion. MicroRNAs (miRNAs) are small, non-coding RNAs that play a crucial role in regulation of gene expression and biological processes of the cells. Herein, we search for a link between the tumor/metastatic-suppressive actions of melatonin and miRNA expression in triple-negative breast cancer cells. We demonstrated that melatonin exerts its anti-tumor actions by reducing proliferation, migration and c-Myc expression of triple negative breast cancer cells. By using Taqman-based assays, we analyzed the expression levels of a set of miRNAs following melatonin treatment of triple negative breast cancer cells and we identified 17 differentially expressed miRNAs, 6 down-regulated and 11 up-regulated. We focused on the anti-metastatic miR-148b and the oncogenic miR-210 both up-regulated by melatonin treatment and studied the effect of their modulation on melatonin-mediated impairment of tumor progression. Surprisingly, when miR-148b or miR-210 were depleted in triple-negative breast cancer cells, using a specific miR-148b sponge or anti-miR-210, melatonin effects on migration inhibition and c-myc downregulation were still visible suggesting that the increase of miR-148b and miR-210 expression observed following melatonin treatment was not required for the efficacy of melatonin action. Nevertheless, ours results suggest that melatonin exhibit a compound for metastatic trait inhibition, especially in MDA-MB-231 breast cancer cells even if a direct link between modulation of expression of certain proteins or miRNAs and melatonin effects has still to be established.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228062PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6996834PMC
April 2020

Investigating the epi-miRNome: identification of epi-miRNAs using transfection experiments.

Epigenomics 2019 11 6;11(14):1581-1599. Epub 2019 Nov 6.

Department of Physics & INFN, University of Torino, 10125, Torino, Italy.

Growing evidence shows a strong interplay between post-transcriptional regulation, mediated by miRNAs (miRs) and epigenetic regulation. Nevertheless, the number of experimentally validated miRs (called epi-miRs) involved in these regulatory circuitries is still very small. We propose a pipeline to prioritize candidate epi-miRs and to identify potential epigenetic interactors of any given miR starting from miR transfection experiment datasets. We identified 34 candidate epi-miRs: 19 of them are known epi-miRs, while 15 are new. Moreover, using an in-house generated gene expression dataset, we experimentally proved that a component of the polycomb-repressive complex 2, the histone methyltransferase enhancer of zeste homolog 2 (EZH2), interacts with miR-214, a well-known prometastatic miR in melanoma and breast cancer, highlighting a miR-214-EZH2 regulatory axis potentially relevant in tumor progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2217/epi-2019-0050DOI Listing
November 2019

Role of miRNAs in tumor and endothelial cell interactions during tumor progression.

Semin Cancer Biol 2020 02 3;60:214-224. Epub 2019 Aug 3.

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy; Dept. Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy; Center for Complex Systems in Molecular Biology and Medicine, University of Torino, Torino, Italy. Electronic address:

Cancer is a multistep disease based on crucial interactions between tumor cells and the microenvironment (extracellular matrix and stroma/immune cells). In fact, during dissemination, tumor cells have to escape from the primary tumor mass, cross the basal membrane, interact with endothelial cells to enter blood vessels (intravasation), survive in the bloodstream, get in contact with endothelial cells again to exit the bloodstream (extravasation) and seed in distant organs. Interactions between tumor and stroma cells are strongly coordinated by microRNAs (miRNAs), small non-coding RNAs able to silence protein coding genes by binding to specific recognition sites, mostly located at the 3' UTR of mature mRNAs. Relevantly, miRNA expression is often altered (overexpression or downregulation) in tumor cells and influenced by stroma cells. At the same time, miRNAs are abundant and essential in stroma cells during tumor cell dissemination and their expression is influenced by tumor cells. In fact, for instance, conditional ablation of Dicer in the endothelium of tumor bearing-mice leads to reduced tumor growth and microvessel density. In this review, we specifically focus on the role of miRNAs in endothelial cells regarding their positive or negative intervention on tumor angiogenesis or lymphoangiogenesis or when tumor cells detach from the tumor mass and intravasate or extravasate in/out of the blood vessels. Examples of pro-angiogenic miRNAs are miR-9 or miR-494, often overexpressed in tumors, which accumulate in tumor cell microvescicles and, therefore, get transferred to endothelial cells where they induce migration and angiogenesis. Differently, miR-200 and miR-128 are often downregulated in tumors and inhibit angiogenesis and lymphoangiogenesis. Instead, miR-126 controls intravasation while miR-146a, miR-214, miR-148b govern extravasation, in a positive or negative manner. Finally, at the end, we summarize opportunities for therapeutic interventions based on miRNAs acting on endothelial cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.semcancer.2019.07.024DOI Listing
February 2020

Antitumoral effects of attenuated Listeria monocytogenes in a genetically engineered mouse model of melanoma.

Oncogene 2019 05 21;38(19):3756-3762. Epub 2019 Jan 21.

Institute of Clinical Physiology, CNR, Pisa, Italy.

Attenuated Listeria monocytogenes (Lm-LLO) represents a valuable anticancer vaccine and drug delivery platform. Here we show that in vitro Lm-LLO causes ROS production and, in turn, apoptotic killing of a wide variety of melanoma cells, irrespectively of their stage, mutational status, sensitivity to BRAF inhibitors or degree of stemness. We also show that, when administered in the therapeutic setting to Braf/Pten genetically engineered mice, Lm-LLO causes a strong decrease in the size and volume of primary melanoma tumors, as well as a reduction of the metastatic burden. At the molecular level, we confirm that the anti-melanoma activity exerted in vivo by Lm-LLO depends also on its ability to potentiate the immune response of the organism against the infected tumor. Our data pave the way to the preclinical testing of listeria-based immunotherapeutic strategies against metastatic melanoma, using a genetically engineered mouse rather than xenograft models.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41388-019-0681-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6756113PMC
May 2019

AGO2 promotes telomerase activity and interaction between the telomerase components TERT and TERC.

EMBO Rep 2019 02 27;20(2). Epub 2018 Dec 27.

Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy.

Telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC) constitute the core telomerase enzyme that maintains the length of telomeres. Telomere maintenance is affected in a broad range of cancer and degenerative disorders. Taking advantage of gain- and loss-of-function approaches, we show that Argonaute 2 (AGO2) promotes telomerase activity and stimulates the association between TERT and TERC AGO2 depletion results in shorter telomeres as well as in lower proliferation rates and We also demonstrate that AGO2 interacts with TERC and with a newly identified sRNA (-sRNA), arising from the H/ACA box of TERC Notably, -sRNA is sufficient to enhance telomerase activity when overexpressed. Analyses of sRNA-Seq datasets show that -sRNA is detected in primary human tissues and increases in tumors as compared to control tissues. Collectively, these data uncover a new layer of complexity in the regulation of telomerase activity by AGO2 and might lay the foundation for new therapeutic targets in tumors and telomere diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.15252/embr.201845969DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6362350PMC
February 2019

Therapeutic Silencing of miR-214 Inhibits Tumor Progression in Multiple Mouse Models.

Mol Ther 2018 08;26(8):2008-2018

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy; Department Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy; Center for Complex Systems in Molecular Biology and Medicine, University of Torino, Torino, Italy. Electronic address:

We previously demonstrated that miR-214 is upregulated in malignant melanomas and triple-negative breast tumors and promotes metastatic dissemination by affecting a complex pathway including the anti-metastatic miR-148b. Importantly, tumor dissemination could be reduced by blocking miR-214 function or increasing miR-148b expression or by simultaneous interventions. Based on this evidence, with the intent to explore the role of miR-214 as a target for therapy, we evaluated the capability of new chemically modified anti-miR-214, R97/R98, to inhibit miR-214 coordinated metastatic traits. Relevantly, when melanoma or breast cancer cells were transfected with R97/R98, anti-miR-214 reduced miR-214 expression and impaired transendothelial migration were observed. Noteworthy, when the same cells were injected in the tail vein of mice, cell extravasation and metastatic nodule formation in lungs were strongly reduced. Thus, suggesting that R97/R98 anti-miR-214 oligonucleotides were able to inhibit tumor cell escaping through the endothelium. More importantly, when R97/R98 anti-miR-214 compounds were systemically delivered to mice carrying melanomas or breast or neuroendocrine pancreatic cancers, a reduced number of circulating tumor cells and lung or lymph node metastasis formation were detected. Similar results were also obtained when AAV8-miR-214 sponges were used in neuroendocrine pancreatic tumors. Based on this evidence, we propose miR-214 as a promising target for anti-metastatic therapies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ymthe.2018.05.020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6094360PMC
August 2018

mTORC1/autophagy-regulated MerTK in mutant BRAFV600 melanoma with acquired resistance to BRAF inhibition.

Oncotarget 2017 Sep 25;8(41):69204-69218. Epub 2017 May 25.

Department of Biomedicine, University Hospital Basel, Basel, Switzerland.

BRAF inhibitors (BRAFi) and the combination therapy of BRAF and MEK inhibitors (MEKi) were recently approved for therapy of metastatic melanomas harbouring the oncogenic BRAFV600 mutation. Although these therapies have shown pronounced therapeutic efficacy, the limited durability of the response indicates an acquired drug resistance that still remains mechanistically poorly understood at the molecular level. We conducted transcriptome gene profiling in BRAFi-treated melanoma cells and identified that Mer tyrosine kinase (MerTK) is specifically upregulated. MerTK overexpression was demonstrated not only in melanomas resistant to BRAFi monotherapy (5 out of 10 samples from melanoma patients) but also in melanoma resistant to BRAFi+MEKi (1 out of 3), although MEKi alone does not affect MerTK. Mechanistically, BRAFi-induced activation of Zeb2 stimulates MerTK in BRAFV600 melanoma through mTORC1-triggered activation of autophagy. Co-targeting MerTK and BRAFV600 significantly reduced tumour burden in xenografted mice, which was pheno-copied by co-inhibition of autophagy and mutant BRAFV600.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.18213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5642473PMC
September 2017

Dysregulation of Blimp1 transcriptional repressor unleashes p130Cas/ErbB2 breast cancer invasion.

Sci Rep 2017 04 25;7(1):1145. Epub 2017 Apr 25.

Department of Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126, Turin, Italy.

ErbB2 overexpression is detected in approximately 20% of breast cancers and is correlated with poor survival. It was previously shown that the adaptor protein p130Cas/BCAR1 is a crucial mediator of ErbB2 transformation and that its overexpression confers invasive properties to ErbB2-positive human mammary epithelial cells. We herein prove, for the first time, that the transcriptional repressor Blimp1 is a novel mediator of p130Cas/ErbB2-mediated invasiveness. Indeed, high Blimp1 expression levels are detected in invasive p130Cas/ErbB2 cells and correlate with metastatic status in human breast cancer patients. The present study, by using 2D and 3D breast cancer models, shows that the increased Blimp1 expression depends on both MAPK activation and miR-23b downmodulation. Moreover, we demonstrate that Blimp1 triggers cell invasion and metastasis formation via its effects on focal adhesion and survival signaling. These findings unravel the previously unidentified role that transcriptional repressor Blimp1 plays in the control of breast cancer invasiveness.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-01332-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5430666PMC
April 2017

PD-L1 up-regulation in melanoma increases disease aggressiveness and is mediated through miR-17-5p.

Oncotarget 2017 Feb;8(9):15894-15911

Human Genetics Foundation (HuGeF), Turin, Italy.

PD-L1 is expressed by a subset of patients with metastatic melanoma (MM) with an unfavorable outcome. Its expression is increased in cells resistant to BRAF or MEK inhibitors (BRAFi or MEKi). However, the function and regulation of expression of PD-L1 remain incompletely understood.After generating BRAFi- and MEKi-resistant cell lines, we observed marked up-regulation of PD-L1 expression. These cells were characterized by a common gene expression profile with up-regulation of genes involved in cell movement. Consistently, in vitro they showed significantly increased invasive properties. This phenotype was controlled in part by PD-L1, as determined after silencing the molecule. Up-regulation of PD-L1 was due to post-transcriptional events controlled by miR-17-5p, which showed an inverse correlation with PD-L1 mRNA. Direct binding between miR-17-5p and the 3'-UTR of PD-L1 mRNA was demonstrated using luciferase reporter assays.In a cohort of 80 BRAF-mutated MM patients treated with BRAFi or MEKi, constitutive expression of PD-L1 in the absence of immune infiltrate, defined the patient subset with the worst prognosis. Furthermore, PD-L1 expression increased in tissue biopsies after the metastatic lesions became resistant to BRAFi or MEKi. Lastly, plasmatic miR-17-5p levels were higher in patients with PD-L1+ than PD-L1- lesions.In conclusion, our findings indicate that PD-L1 expression induces a more aggressive behavior in melanoma cells. We also show that PD-L1 up-regulation in BRAFi or MEKi-resistant cells is partly due to post-transcriptional mechanisms that involve miR-17-5p, suggesting that miR-17-5p may be used as a marker of PD-L1 expression by metastatic lesions and ultimately a predictor of responses to BRAFi or MEKi.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.15213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5362532PMC
February 2017

The RNA-binding protein ESRP1 promotes human colorectal cancer progression.

Oncotarget 2017 Feb;8(6):10007-10024

Institute of Biostructure and Bioimaging, CNR, Department of Molecular Biotechnology and Health Sciences, University of Turin, Italy.

Epithelial splicing regulatory protein 1 (ESRP1) is an epithelial cell-specific RNA binding protein that controls several key cellular processes, like alternative splicing and translation. Previous studies have demonstrated a tumor suppressor role for this protein. Recently, however, a pro-metastatic function of ESRP1 has been reported. We thus aimed at clarifying the role of ESRP1 in Colorectal Cancer (CRC) by performing loss- and gain-of-function studies, and evaluating tumorigenesis and malignancy with in vitro and in vivo approaches. We found that ESRP1 plays a role in anchorage-independent growth of CRC cells. ESRP1-overexpressing cells grown in suspension showed enhanced fibroblast growth factor receptor (FGFR1/2) signalling, Akt activation, and Snail upregulation. Moreover, ESRP1 promoted the ability of CRC cells to generate macrometastases in mice livers. High ESRP1 expression may thus stimulate growth of cancer epithelial cells and promote colorectal cancer progression. Our findings provide mechanistic insights into a previously unreported, pro-oncogenic role for ESRP1 in CRC, and suggest that fine-tuning the level of this RNA-binding protein could be relevant in modulating tumor growth in a subset of CRC patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.14318DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5354637PMC
February 2017

VEGF blockade enhances the antitumor effect of BRAFV600E inhibition.

EMBO Mol Med 2017 02;9(2):219-237

Department of Oncology, University of Torino, Candiolo, Italy

The development of resistance remains a major obstacle to long-term disease control in cancer patients treated with targeted therapies. In BRAF-mutant mouse models, we demonstrate that although targeted inhibition of either BRAF or VEGF initially suppresses the growth of BRAF-mutant tumors, combined inhibition of both pathways results in apoptosis, long-lasting tumor responses, reduction in lung colonization, and delayed onset of acquired resistance to the BRAF inhibitor PLX4720. As well as inducing tumor vascular normalization and ameliorating hypoxia, this approach induces remodeling of the extracellular matrix, infiltration of macrophages with an M1-like phenotype, and reduction in cancer-associated fibroblasts. At the molecular level, this therapeutic regimen results in a de novo transcriptional signature, which sustains and explains the observed efficacy with regard to cancer progression. Collectively, our findings offer new biological rationales for the management of clinical resistance to BRAF inhibitors based on the combination between BRAF inhibitors with anti-angiogenic regimens.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.15252/emmm.201505774DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5286370PMC
February 2017

miR-214 and miR-148b Targeting Inhibits Dissemination of Melanoma and Breast Cancer.

Cancer Res 2016 09 21;76(17):5151-62. Epub 2016 Jun 21.

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy. Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy. Center for Complex Systems in Molecular Biology and Medicine, University of Torino, Torino, Italy.

miR-214 and miR-148b have been proposed to antagonize the effects of each other in enabling or blocking metastasis, respectively. In this study, we provide evidence deepening their role and interrelationship in the process of metastatic dissemination. Depleting miR-214 or elevating miR-148b blocked the dissemination of melanoma or breast cancer cells, an effect that could be accentuated by dual alteration. Mechanistic investigations indicated that dual alteration suppressed passage of malignant cells through the blood vessel endothelium by reducing expression of the cell adhesion molecules ITGA5 and ALCAM. Notably, transendothelial migration in vitro and extravasation in vivo impaired by singly alternating miR-214 or miR-148b could be overridden by overexpression of ITGA5 or ALCAM in the same tumor cells. In clinical specimens of primary breast cancer or metastatic melanoma, we found a positive correlation between miR-214 and ITGA5 or ALCAM along with an inverse correlation of miR-214 and miR-148b in the same specimens. Our findings define an antagonistic relationship of miR-214 and miR-148b in determining the dissemination of cancer cells via tumor-endothelial cell interactions, with possible implications for microRNA-mediated therapeutic interventions aimed at blocking cancer extravasation. Cancer Res; 76(17); 5151-62. ©2016 AACR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-15-1322DOI Listing
September 2016

miR-146a Exerts Differential Effects on Melanoma Growth and Metastatization.

Mol Cancer Res 2016 06;14(6):548-62

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy. Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy. Center for Molecular Systems Biology, University of Torino, Torino, Italy.

Unlabelled: Malignant melanoma is the most aggressive form of skin cancer; therefore, it is crucial to disclose its underlying molecular mechanisms. MicroRNAs (miRNAs) are small endogenous noncoding RNAs able to posttranscriptionally downregulate the expression of direct target genes. Using a melanoma progression model, miR-146a was identified as a key double-acting player in melanoma malignancy. In fact, miR-146a is able to enhance tumor growth, while it suppresses dissemination. It was determined that miR-146a coordinated melanoma cell growth by its direct targets lunatic fringe (LFNG) and NUMB, which operate on the NOTCH/PTEN/Akt pathway; while inhibition of metastasis formation was linked to decreased expression of ITGAV and ROCK1. Relevantly, miR-146a expression correlated with melanoma recurrence and was enriched in both patient-derived melanoma and cutaneous metastasis specimens, while its direct targets were depleted. However, miR-146a levels drop in circulating tumor cells (CTCs), suggesting the necessity for miR-146a expression to fluctuate during tumor progression in order to favor tumor growth and allow dissemination. This study reconciles the contradictory biologic functions of miR-146a in melanoma progression and unravels distinct molecular mechanisms that need to be considered for therapeutic interventions.

Implications: miR-146a controls melanoma progression in a dual way, promoting growth and inhibiting dissemination; however, it is poorly expressed in CTCs, resulting in overall tumor spreading and distant-site colonization. Mol Cancer Res; 14(6); 548-62. ©2016 AACR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1541-7786.MCR-15-0425-TDOI Listing
June 2016

CyTRANSFINDER: a Cytoscape 3.3 plugin for three-component (TF, gene, miRNA) signal transduction pathway construction.

BMC Bioinformatics 2016 Apr 8;17:157. Epub 2016 Apr 8.

Department of Control and Computer Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino, 10129, Italy.

Background: Biological research increasingly relies on network models to study complex phenomena. Signal Transduction Pathways are molecular circuits that model how cells receive, process, and respond to information from the environment providing snapshots of the overall cell dynamics. Most of the attempts to reconstruct signal transduction pathways are limited to single regulator networks including only genes/proteins. However, networks involving a single type of regulator and neglecting transcriptional and post-transcriptional regulations mediated by transcription factors and microRNAs, respectively, may not fully reveal the complex regulatory mechanisms of a cell. We observed a lack of computational instruments supporting explorative analysis on this type of three-component signal transduction pathways.

Results: We have developed CyTRANSFINDER, a new Cytoscape plugin able to infer three-component signal transduction pathways based on user defined regulatory patterns and including miRNAs, TFs and genes. Since CyTRANSFINDER has been designed to support exploratory analysis, it does not rely on expression data. To show the potential of the plugin we have applied it in a study of two miRNAs that are particularly relevant in human melanoma progression, miR-146a and miR-214.

Conclusions: CyTRANSFINDER supports the reconstruction of small signal transduction pathways among groups of genes. Results obtained from its use in a real case study have been analyzed and validated through both literature data and preliminary wet-lab experiments, showing the potential of this tool when performing exploratory analysis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12859-016-0964-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4826505PMC
April 2016

MSC-regulated microRNAs converge on the transcription factor FOXP2 and promote breast cancer metastasis.

Cell Stem Cell 2014 Dec 16;15(6):762-74. Epub 2014 Oct 16.

Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. Electronic address:

Mesenchymal stem/stromal cells (MSCs) are progenitor cells shown to participate in breast tumor stroma formation and to promote metastasis. Despite expanding knowledge of their contributions to breast malignancy, the underlying molecular responses of breast cancer cells (BCCs) to MSC influences remain incompletely understood. Here, we show that MSCs cause aberrant expression of microRNAs, which, led by microRNA-199a, provide BCCs with enhanced cancer stem cell (CSC) properties. We demonstrate that such MSC-deregulated microRNAs constitute a network that converges on and represses the expression of FOXP2, a forkhead transcription factor tightly associated with speech and language development. FOXP2 knockdown in BCCs was sufficient in promoting CSC propagation, tumor initiation, and metastasis. Importantly, elevated microRNA-199a and depressed FOXP2 expression levels are prominent features of malignant clinical breast cancer and are associated significantly with poor survival. Our results identify molecular determinants of cancer progression of potential utility in the prognosis and therapy of breast cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.stem.2014.10.001DOI Listing
December 2014

miR-214 as a key hub that controls cancer networks: small player, multiple functions.

J Invest Dermatol 2015 Apr 11;135(4):960-969. Epub 2014 Dec 11.

Molecular Biotechnology Center (MBC), Torino, Italy; Department of Molecular Biotechnology and Health Sciences, Torino, Italy; Center for Molecular Systems Biology, University of Torino, Torino, Italy. Electronic address:

MicroRNAs are short regulatory RNAs that are able to post-transcriptionally modulate gene expression and that have crucial roles in the control of physiological and pathological processes including cancer onset, growth, and progression. miR-214, located inside the sequence of the long noncoding Dmn3os transcript, contributes to the regulation of normal and cancer cell biology, even if it operates in a context-dependent and sometimes contradictory manner. miR-214 is deregulated in several human tumors including melanoma, breast, ovarian, gastric, and hepatocellular carcinomas. miR-214's pleiotropic and tumor-specific contribution to various cancer formation and progression hallmarks is achieved via its several target genes. In fact, miR-214 behaves as a key hub by coordinating fundamental signaling networks such as PTEN/AKT, β-catenin, and tyrosine kinase receptor pathways. Interestingly, miR-214 also regulates the levels of crucial gene expression modulators: the epigenetic repressor Ezh2, "genome guardian" p53, transcription factors TFAP2, and another microRNA, miR-148b. Thus, miR-214 seems to have essential roles in coordinating tumor proliferation, stemness, angiogenesis, invasiveness, extravasation, metastasis, resistance to chemotherapy, and microenvironment. The sum of current literature reports suggests that miR-214 is a molecular hub involved in the control of cancer networks and, as such, could be a potential diagnostic/prognostic biomarker and target for therapeutic intervention.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/jid.2014.479DOI Listing
April 2015

miR-223 is a coordinator of breast cancer progression as revealed by bioinformatics predictions.

PLoS One 2014 6;9(1):e84859. Epub 2014 Jan 6.

Molecular Biotechnology Center (MBC), University of Torino, Torino, Italy ; Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy ; Center for Molecular Systems Biology, University of Torino, Torino, Italy.

MicroRNAs are single-stranded non-coding RNAs that simultaneously down-modulate the expression of multiple genes post-transcriptionally by binding to the 3'UTRs of target mRNAs. Here we used computational methods to predict microRNAs relevant in breast cancer progression. Specifically, we applied different microRNA target prediction algorithms to various groups of differentially expressed protein-coding genes obtained from four breast cancer datasets. Six potential candidates were identified, among them miR-223, previously described to be highly expressed in the tumor microenvironment and known to be actively transferred into breast cancer cells. To investigate the function of miR-223 in tumorigenesis and to define its molecular mechanism, we overexpressed miR-223 in breast cancer cells in a transient or stable manner. Alternatively we overexpressed miR-223 in mouse embryonic fibroblasts or HEK293 cells and used their conditioned medium to treat tumor cells. With both approaches, we obtained elevated levels of miR-223 in tumor cells and observed decreased migration, increased cell death in anoikis conditions and augmented sensitivity to chemotherapy but no effect on adhesion and proliferation. The analysis of miR-223 predicted targets revealed enrichment in cell death and survival-related genes and in pathways frequently altered in breast cancer. Among these genes, we showed that protein levels for STAT5A, ITGA3 and NRAS were modulated by miR-223. In addition, we proved that STAT5A is a direct miR-223 target and highlighted a possible correlation between miR-223 and STAT5A in migration and chemotherapy response. Our investigation revealed that a computational analysis of cancer gene expression datasets can be a relevant tool to identify microRNAs involved in cancer progression and that miR-223 has a prominent role in breast malignancy that could potentially be exploited therapeutically.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084859PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3882278PMC
September 2014

miR-21 coordinates tumor growth and modulates KRIT1 levels.

Biochem Biophys Res Commun 2013 Aug 18;438(1):90-6. Epub 2013 Jul 18.

Molecular Biotechnology Center, University of Torino, Torino, Italy.

miR-21 is overexpressed in tumors and it displays oncogenic activity. Here, we show that expression of miR-21 in primary tumors anticorrelates with KRIT1/CCM1, an interacting partner of the Ras-like GTPase Rap1, involved in Cerebral Cavernous Malformations (CCM). We present evidences that miR-21 silences KRIT1 by targeting its mRNA 3'UTR and that this interaction is involved in tumor growth control. In fact, miR-21 over-expression or KRIT1 knock-down promote anchorage independent tumor cell growth compared to controls, whereas the opposite is observed when anti-miR-21 or KRIT1 overexpression are employed. Our findings suggest that miR-21 promotes tumor cell growth, at least in part, by down-modulating the potential tumor suppressor KRIT1.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2013.07.031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3750217PMC
August 2013

Identification of p130Cas/ErbB2-dependent invasive signatures in transformed mammary epithelial cells.

Cell Cycle 2013 Aug 28;12(15):2409-22. Epub 2013 Jun 28.

Molecular Biotechnology Center (MBC); Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino, Italy.

Understanding transcriptional changes during cancer progression is of crucial importance to develop new and more efficacious diagnostic and therapeutic approaches. It is well known that ErbB2 is overexpressed in about 25% of human invasive breast cancers. We have previously demonstrated that p130Cas overexpression synergizes with ErbB2 in mammary cell transformation and promotes ErbB2-dependent invasion in three-dimensional (3D) cultures of human mammary epithelial cells. Here, by comparing coding and non-coding gene expression profiles, we define the invasive signatures associated with concomitant p130Cas overexpression and ErbB2 activation in 3D cultures of mammary epithelial cells. Specifically, we have found that genes involved in amino acids synthesis (CBS, PHGDH), cell motility, migration (ITPKA, PRDM1), and angiogenesis (HEY1) are upregulated, while genes involved in inflammatory response (SAA1, S100A7) are downregulated. In parallel, we have shown that the expression of specific miRNAs is altered. Among these, miR-200b, miR-222, miR-221, miR-R210, and miR-424 are upregulated, while miR-27a, miR-27b, and miR-23b are downregulated. Overall, this study presents, for the first time, the gene expression changes underlying the invasive behavior following p130Cas overexpression in an ErbB2 transformed mammary cell model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4161/cc.25415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3841320PMC
August 2013

miR-214 coordinates melanoma progression by upregulating ALCAM through TFAP2 and miR-148b downmodulation.

Cancer Res 2013 Jul 10;73(13):4098-111. Epub 2013 May 10.

Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy.

Malignant melanoma is one of the most aggressive human cancers, but the mechanisms governing its metastatic dissemination are not fully understood. Upregulation of miR-214 and ALCAM and the loss of TFAP2 expression have been implicated in this process, with TFAP2 a direct target of miR-214. Here, we link miR-214 and ALCAM as well as identify a core role for miR-214 in organizing melanoma metastasis. miR-214 upregulated ALCAM, acting transcriptionally through TFAP2 and also posttranscriptionally through miR-148b (itself controlled by TFAP2), both negative regulators of ALCAM. We also identified several miR-214-mediated prometastatic functions directly promoted by ALCAM. Silencing ALCAM in miR-214-overexpressing melanoma cells reduced cell migration and invasion without affecting growth or anoikis in vitro, and it also impaired extravasation and metastasis formation in vivo. Conversely, cell migration and extravasation was reduced in miR-214-overexpressing cells by upregulation of either miR-148b or TFAP2. These findings were consistent with patterns of expression of miR-214, ALCAM, and miR-148b in human melanoma specimens. Overall, our results define a pathway involving miR-214, miR-148b, TFAP2, and ALCAM that is critical for establishing distant metastases in melanoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/0008-5472.CAN-12-3686DOI Listing
July 2013

miR-135b coordinates progression of ErbB2-driven mammary carcinomas through suppression of MID1 and MTCH2.

Am J Pathol 2013 Jun 23;182(6):2058-70. Epub 2013 Apr 23.

Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Torino, Torino, Italy.

In an attempt to reveal deregulated miRNAs associated with the progression of carcinomas developed in BALB-neuT transgenic mice, we found increased expression of miR-135b during malignancy. Relevantly, we observed that miR-135b is up-regulated in basal or normal-like human breast cancers, and it correlates with patient survival and early metastatization. Therefore, we investigated its biological functions by modulating its expression (up- or down-regulation) in mammary tumor cells. Although no effect was observed on proliferation in cell culture and in orthotopically injected mice, miR-135b was able to control cancer cell stemness in a mammosphere assay, anchorage-independent growth in vitro, and lung cancer cell dissemination in mice after tail vein injections. Focusing on the miR-135b molecular mechanism, we observed that miR-135b controls malignancy via its direct targets, midline 1 (MID1) and mitochondrial carrier homolog 2 (MTCH2), as proved by biochemical and functional rescuing/phenocopying experiments. Consistently, an anti-correlation between miR-135b and MID1 or MTCH2 was found in human primary tumor samples. In conclusion, our research led us to the identification of miR-135b and its targets, MID1 and MTCH2, as relevant coordinators of mammary gland tumor progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajpath.2013.02.046DOI Listing
June 2013

miR148b is a major coordinator of breast cancer progression in a relapse-associated microRNA signature by targeting ITGA5, ROCK1, PIK3CA, NRAS, and CSF1.

FASEB J 2013 Mar 11;27(3):1223-35. Epub 2012 Dec 11.

Molecular Biotechnology Center (MBC), University of Torino, Via Nizza, 52, 10126 Torino, Italy.

Breast cancer is often fatal during its metastatic dissemination. To unravel the role of microRNAs (miRs) during malignancy, we analyzed miR expression in 77 primary breast carcinomas and identified 16 relapse-associated miRs that correlate with survival and/or distinguish tumor subtypes in different datasets. Among them, miR-148b, down-regulated in aggressive breast tumors, was found to be a major coordinator of malignancy. In fact, it is able to oppose various steps of tumor progression when overexpressed in cell lines by influencing invasion, survival to anoikis, extravasation, lung metastasis formation, and chemotherapy response. miR-148b controls malignancy by coordinating a novel pathway involving over 130 genes and, in particular, it directly targets players of the integrin signaling, such as ITGA5, ROCK1, PIK3CA/p110α, and NRAS, as well as CSF1, a growth factor for stroma cells. Our findings reveal the importance of the identified 16 miRs for disease outcome predictions and suggest a critical role for miR-148b in the control of breast cancer progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1096/fj.12-214692DOI Listing
March 2013

p130Cas/Cyclooxygenase-2 axis in the control of mesenchymal plasticity of breast cancer cells.

Breast Cancer Res 2012 Oct 26;14(5):R137. Epub 2012 Oct 26.

Introduction: Intrinsic plasticity of breast carcinoma cells allows them to undergo a transient and reversible conversion into mesenchymal cells to disseminate into distant organs, where they can re-differentiate to an epithelial-like status to form a cohesive secondary mass. The p130Cas scaffold protein is overexpressed in human ER+ and HER2+ breast cancer where it contributes to cancer progression, invasion and resistance to therapy. However, its role in regulating mesenchymal aggressive breast cancer cells remains to be determined. The aim of this study was to investigate the molecular and functional involvement of this adaptor protein in breast cancer cell plasticity.

Methods: We used silencing strategies and rescue experiments to evaluate phenotypic and biochemical changes from mesenchymal to epithelial traits in breast tumor cell lines. In the mouse A17 cell model previously related to mesenchymal cancer stem cells and basal-like breast cancer, we biochemically dissected the signaling pathways involved and performed functional in vivo tumor growth ability assays. The significance of the signaling platform was assessed in a human setting through the use of specific inhibitors in aggressive MDA-MB-231 subpopulation LM2-4175 cells. To evaluate the clinical relevance of the results, we analyzed publicly available microarray data from the Netherlands Cancer Institute and from the Koo Foundation Sun Yat-Sen Cancer Center.

Results: We show that p130Cas silencing induces loss of mesenchymal features, by downregulating Vimentin, Snail, Slug and Twist transcriptional factors, resulting in the acquirement of epithelial-like traits. Mechanistically, p130Cas controls Cyclooxygenase-2 transcriptional expression, which in turn contributes to p130Cas-dependent maintenance of mesenchymal phenotype. This cascade of events also compromises in vivo tumor growth through inhibition of cell signaling controlling cell cycle progression. c-Src and JNK kinases are sequential players in p130Cas/ Cyclooxygenase-2 axis and their pharmacological inhibition is sufficient to downregulate Cyclooxygenase-2 leading to an epithelial phenotype. Finally, in silico microarray data analysis indicates that p130Cas and Cyclooxygenase-2 concomitant overexpression predicts poor survival and high probability of breast tumor recurrence.

Conclusions: Overall, these data identify a new p130Cas/Cyclooxygenase-2 axis as a crucial element in the control of breast tumor plasticity, opening new therapeutic strategies leading to inhibition of these pathways in aggressive breast carcinoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/bcr3342DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4053116PMC
October 2012

3-phosphoinositide-dependent kinase 1 controls breast tumor growth in a kinase-dependent but Akt-independent manner.

Neoplasia 2012 Aug;14(8):719-31

Institute for Cancer Research and Treatment, Candiolo, Italy.

3-phosphoinositide-dependent protein kinase 1 (PDK1) is the pivotal element of the phosphatidylinositol 3 kinase (PI3K) signaling pathway because it phosphorylates Akt/PKB through interactions with phosphatidylinositol 3,4,5 phosphate. Recent data indicate that PDK1 is overexpressed in many breast carcinomas and that alterations of PDK1 are critical in the context of oncogenic PI3K activation. However, the role of PDK1 in tumor progression is still controversial. Here, we show that PDK1 is required for anchorage-independent and xenograft growth of breast cancer cells harboring either PI3KCA or KRAS mutations. In fact, PDK1 silencing leads to increased anoikis, reduced soft agar growth, and pronounced apoptosis inside tumors. Interestingly, these phenotypes are reverted by PDK1 wild-type but not kinase-dead mutant, suggesting a relevant role of PDK1 kinase activity, even if PDK1 is not relevant for Akt activation here. Indeed, the expression of constitutively active forms of Akt in PDK1 knockdown cells is unable to rescue the anchorage-independent growth. In addition, Akt down-regulation and pharmacological inhibition do not inhibit the effects of PDK1 overexpression. In summary, these results suggest that PDK1 may contribute to breast cancer, even in the absence of PI3K oncogenic mutations and through both Akt-dependent and Akt-independent mechanisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3431179PMC
http://dx.doi.org/10.1593/neo.12856DOI Listing
August 2012

High IGFBP2 expression correlates with tumor severity in pediatric rhabdomyosarcoma.

Am J Pathol 2011 Nov 13;179(5):2611-24. Epub 2011 Sep 13.

Department of Biology and the Interdepartmental Research Center in Innovative Biotechnology (CRIBI), Padova Hospital, University of Padova, Padova, Italy.

Rhabdomyosarcoma (RMS) is the most common childhood sarcoma and is identified as either the embryonal or alveolar (ARMS) subtype. In approximately 75% of cases, ARMSs are characterized by specific chromosomal translocations that involve PAX and FKHR genes. ARMS gene expression signatures vary, depending on the presence or absence of the translocations. Insulin-like growth factor-binding protein 2 (IGFBP2) is strongly overexpressed in translocation-negative RMS. Because IGFBP2 is associated with tumorigenesis, we investigated its functional role in RMS. An analysis of IGFBP2 distribution in RMS cell lines revealed a strong accumulation in the Golgi complex, in which morphological characteristics appeared peculiarly modified. After silencing IGFBP2 expression, our microarray analysis revealed mostly cell cycle and actin cytoskeleton gene modulations. In parallel, IGFBP2-silenced cells showed reduced cell cycle and rates of invasion and decreased seeding in the lungs after tail vein injections in immunodeficient mice. An analysis of IGFBP2 mRNA and protein localization in human tumors showed abnormal protein accumulation in the Golgi complex, mostly in PAX/FKHR-negative RMS. Moreover, an analysis of patients with RMS revealed the presence of conspicuous circulating levels of IGFBP2 proteins in children with highly aggressive RMS tumors. Taken together, our data provide evidence that IGFBP2 contributes to tumor progression and that it could be used as a marker to better classify clinical and biological risks in RMS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajpath.2011.07.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3204033PMC
November 2011