Publications by authors named "Gustavo Noriz Berardinelli"

15 Publications

  • Page 1 of 1

Microsatellite Instability Is Rare in the Admixed Brazilian Population of Non-Small Cell Lung Cancer: A Cohort of 526 Cases.

Pathobiology 2021 Nov 15:1-6. Epub 2021 Nov 15.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

Background: Microsatellite instability (MSI) in non-small cell lung cancer (NSCLC) is uncommon; however, most studies refer to European and Asian populations. There are currently no data on MSI frequency in highly admixed populations, such as the one represented by Brazilian NSCLC patients.

Aim: This study aimed to evaluate the frequency of MSI in Brazilian NSCLC patients.

Methods: We evaluated 526 patients diagnosed with NSCLC at the Barretos Cancer Hospital (Brazil). The molecular MSI evaluation was performed using a hexa-plex marker panel by polymerase chain reaction followed by fragment analysis. The mutation profile of MSI-positive cases was performed using next-generation sequencing.

Results: Only 1 patient was MSI positive (0.19%). This patient was a female, white, and active smoker, and she was diagnosed with clinical stage IV lung adenocarcinoma at 75 years old. The molecular profile exhibited 4 Tumor Protein p53 (TP53) mutations and the absence of actionable mutations in the Epidermal Growth Factor Receptor (EGFR), Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS), or V-Raf Murine Sarcoma Viral Oncogene Homolog B1 (BRAF) genes.

Conclusions: The frequency of MSI in Brazilian NSCLC patients is equally rare, a finding that is consistent with the current literature based on other populations such as Europeans, North Americans, and Asians.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000520023DOI Listing
November 2021

A 4-Gene Signature Associated With Recurrence in Low- and Intermediate-Risk Endometrial Cancer.

Front Oncol 2021 17;11:729219. Epub 2021 Aug 17.

Department of Gynecologic Oncology, Barretos Cancer Hospital, Barretos, Brazil.

Background: The molecular profile of endometrial cancer has become an important tool in determining patient prognosis and their optimal adjuvant treatment. In addition to The Cancer Genome Atlas (TCGA), simpler tools have been developed, such as the Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE). We attempted to determine a genetic signature to build a recurrence risk score in patients diagnosed with low- and intermediate-risk endometrial cancer.

Methods: A case-control study was conducted. The eligible patients were women diagnosed with recurrence low- and intermediate-risk endometrial cancer between January 2009 and December 2014 at a single institution; the recurrence patients were matched to two nonrecurrence patients with the same diagnosis by age and surgical staging. Following RNA isolation of 51 cases, 17 recurrence and 34 nonrecurrence patients, the expression profile was determined using the , which contains 770 genes.

Results: The expression profile was successfully characterized in 49/51 (96.1%) cases. We identified 12 genes differentially expressed between the recurrence and nonrecurrence groups. The ROC curve for each gene was generated, and all had AUCs higher than 0.7. After backward stepwise logistic regression, four genes were highlighted: . The recurrence risk score was calculated, leading to a ROC curve of the 4-gene model with an AUC of 0.93, sensitivity of 100%, and specificity of 72.7%.

Conclusion: We identified a four-gene signature that may be associated with recurrence in patients with low- and intermediate-risk endometrial cancer. This finding suggests a new prognostic factor in this poorly explored group of patients with endometrial cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fonc.2021.729219DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8416164PMC
August 2021

Methylation profile of colon cancer genes in colorectal precursor lesions and tumor tissue: perspectives for screening.

Scand J Gastroenterol 2021 Aug 3;56(8):920-928. Epub 2021 Jul 3.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

Aims: Epigenetic alterations of genes involved in colorectal carcinogenesis are likely to be informative biomarkers for early detection. We assessed the methylation profile of a panel of seven colon cancer-related genes comparing normal colon, colorectal cancer (CRC) precursor lesions and cancer tissues from a Brazilian cohort.

Methods: The cohort comprised 114 CRC patients, including 40 matched normal tissue, 47 patients with adenomas, 33 with serrated polyps and 8 with normal colonic biopsy. DNA methylation status of , , , , , and was determined by pyrosequencing and correlated with clinicopathological features. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for all genes using cancer endpoint.

Results: The most frequently methylated genes in cancer and in precancer lesions were , , and , ranging from 55.3 to 95% of the samples. Overall, the frequency of methylation of these four genes in normal colonic tissue was significantly lower as compared to cancer or precursor lesions both in adenoma-carcinoma ( < .001 and  < .050) and serrated (sessile-serrated lesion) ( < .001 and  < .050) pathways. Additionally, sensitivity for the cancer endpoint ranged from 65.6 to 91.8%, and specificity from 17.9 to 62.9% for , , , and genes. Moreover, the comethylation of ≥4 genes was higher in sessile-serrated lesion (87.5%) and conventional adenomas (78.7%) than in hyperplastic polyps (43.7%) ( = .025) and was significantly associated with proximal cancers ( = .042).

Conclusions: Our study suggests the DNA methylation can constitute potential biomarkers in CRC screening of Brazilian population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/00365521.2021.1922744DOI Listing
August 2021

Clinicopathological and molecular characterization of Brazilian families at risk for Lynch syndrome.

Cancer Genet 2021 06 14;254-255:82-91. Epub 2021 Feb 14.

Molecular Diagnosis Laboratory, Barretos Cancer Hospital, Barretos, São Paulo, Brazil; Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, São Paulo, Brazil; Pele Pequeno Principe Research Institute, Curitiba, Brazil; Faculdades Pequeno Principe, Curitiba, Brazil. Electronic address:

Lynch syndrome (LS), is the most common hereditary colorectal cancer syndrome. However, it is poorly characterized in Brazil. Therefore, we aimed to determine the spectrum of pathogenic variants in Mismatch Repair (MMR) genes and investigate the MLH1 promotor methylation role as a second hit in LS tumors. Tumor screening through microsatellite instability and immunohistochemistry for MMR proteins was performed in 323 cases who met clinical criteria. BRAF-V600E and MLH1 promoter methylation were analyzed for all MLH1-deficient tumors. Patients with MMR deficient tumor proceeded to germline genetic testing. MMR deficient tumors were detected in 41% of patients recruited. About half of patients carried a pathogenic germline variant. Two recurrent variants in MLH1 and three novel pathogenic variants were identified. Furthermore, pathogenic germline variants with concomitant somatic MLH1 hypermethylation were found in 6% of cases. Predictive genetic testing was offered to 387 relatives. Overall, 127 tumors were diagnosed in 100 LS patients, from 62 unrelated families. Our molecular data provide new information about the spectrum of MMR mutations, which contributes to a better characterization of LS in Brazil. Furthermore, we call attention to the possibility of failure in the diagnosis of germline MLH1 mutation carriers when somatic MLH1 hypermethylation is used to rule out LS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cancergen.2021.02.003DOI Listing
June 2021

Pyknon-Containing Transcripts Are Downregulated in Colorectal Cancer Tumors, and Loss of Is Associated With Worse Patient Outcome.

Front Genet 2020 12;11:581454. Epub 2020 Nov 12.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

Pyknons are specific human/primate-specific DNA motifs at least 16 nucleotides long that are repeated in blocks in intergenic and intronic regions of the genome and can be located in a new class of non-coding RNAs of variable length. Recent studies reported that pyknon deregulation could be involved in the carcinogenesis process, including colorectal cancer. We evaluated the expression profile of a set of 12 pyknons in a set of molecularly characterized colorectal cancer (CRC) patients. The pyknons (, , , , , , , , , , , and ) expression was determined by qRT-PCR. A pilot analysis of 20 cases was performed, and consistent results were obtained for , , , , and . Further, the expression of the selected pyknons was evaluated in 73 CRC cases. Moreover, in 52 patients, we compared the expression profile in both tumor and normal tissues. All five pyknons analyzed showed significantly lower expression levels in the tumor compared to normal tissue. It was observed an association between expression of with mutations ( = 0.029), to histologic grade ( = 0.035), and to clinical staging ( = 0.016). Moreover, levels of were significantly associated with the patient's poor overall survival ( = 0.04). We reported the significant downregulation of pyknons motifs in tumor tissue compared with the normal counterpart, and the association of lower expression with worse patient outcome. Further studies are needed to extend and validate these findings and determine the clinical-pathological impact.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fgene.2020.581454DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7693444PMC
November 2020

Role of Genetic Ancestry in 1,002 Brazilian Colorectal Cancer Patients From Barretos Cancer Hospital.

Front Oncol 2020 4;10:145. Epub 2020 Mar 4.

Molecular Oncology Research Centre, Barretos Cancer Hospital, Barretos, Brazil.

Colorectal cancer (CRC) is the third most frequent and the second deadliest cancer worldwide. The ethnic structure of the population has been gaining prominence as a cancer player. The purpose of this study was to determine the genetic ancestry of Brazilian CRC patients. Moreover, we intended to interrogate its impact on patients' clinicopathological features. Retrospective observational cohort study with 1,002 patients with CRC admitted from 2000 to 2014 at Barretos Cancer Hospital. Following tumor DNA isolation, genetic ancestry was assessed using a specific panel of 46 ancestry informative markers. Survival rates were obtained by the Kaplan-Meier method, and the log-rank test was used to compare the survival curves. Multivariable Cox proportional regression models were used to estimate hazard ratios (HRs). We observed considerable admixture in the genetic composition, with the following average proportions: European 74.2%, African 12.7%, Asian 6.5%, and Amerindian 6.6%. The multivariate analysis for cancer-specific survival showed that clinical stage, lymphovascular invasion, and the presence of recurrence were associated with an increased relative risk of death from cancer ( < 0.05). High African proportion was associated with younger age at diagnosis, while high Amerindian proportion was associated with the mucinous histological subtype. This represents the larger assessment of genetic ancestry in a population of Brazilian patients with CRC. Brazilian CRC patients exhibited similar clinicopathological features as described in Western countries. Genetic ancestry components corroborated the significant admixture, and importantly, patients with high African proportion develop cancer at a younger age.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fonc.2020.00145DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7065467PMC
March 2020

Microbiota Profile and Impact of in Colorectal Cancer Patients of Barretos Cancer Hospital.

Front Oncol 2019 29;9:813. Epub 2019 Aug 29.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

Microbial diversity has been pointed out as a major factor in the development and progression of colorectal cancer (CRC). We sought to explore the richness and abundance of the microbial community of a series of colorectal tumor samples treated at Barretos Cancer Hospital, Brazil, through 16S rRNA sequencing. The presence and the impact of () DNA in CRC prognosis was further evaluated by qPCR in a series of 152 CRC cases. An enrichment for potentially oncogenic bacteria in CRC was observed, with being the most abundant genus in the tumor tissue. In the validation dataset, was detected in 35/152 (23.0%) of fresh-frozen tumor samples and in 6/57 (10.5%) of paired normal adjacent tissue, with higher levels in the tumor ( = 0.0033). DNA in the tumor tissue was significantly associated with proximal tumors ( = 0.001), higher depth of invasion ( = 0.014), higher clinical stages ( = 0.033), poor differentiation ( = 0.011), MSI-positive status ( < 0.0001), BRAF mutated tumors ( < 0.0001), and the loss of expression of mismatch-repair proteins MLH1 ( < 0.0001), MSH2 ( = 0.003), and PMS2 ( < 0.0001). Moreover, the presence of DNA in CRC tissue was also associated with a worse patient cancer-specific survival (69.9 vs. 82.2% in 5 years; = 0.028) and overall survival (63.5 vs. 76.5%; = 0.037). Here we report, for the first time, the association of presence with important clinical and molecular features in a Brazilian cohort of CRC patients. Tumor detection and classification based on the gut microbiome might provide a promising approach to improve the prediction of patient outcome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fonc.2019.00813DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6727361PMC
August 2019

Mutation profiling of cancer drivers in Brazilian colorectal cancer.

Sci Rep 2019 09 23;9(1):13687. Epub 2019 Sep 23.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

The molecular basis of colorectal cancer (CRC) can guide patient prognosis and therapy. In Brazil, knowledge on the CRC mutation landscape is limited. Here, we investigated the mutation profile of 150 cancer-related genes by next-generation sequencing and associated with microsatellite instability (MSI) and genetic ancestry in a series of 91 Brazilian CRC patients. Driver mutations were found in the APC (71.4%), TP53 (56.0%), KRAS (52.7%), PIK3CA (15.4%) and FBXW7 (10.9%) genes. Overall, genes in the MAPK/ERK, PIK3/AKT, NOTCH and receptor tyrosine kinase signaling pathways were mutated in 68.0%, 23.1%, 16.5%, and 15.3% of patients, respectively. MSI was found in 13.3% of tumors, most of which were proximal (52.4%, P< 0.001) and had a high mutation burden. European genetic ancestry was predominant (median of 83.1%), followed by Native American (4.1%), Asian (3.4%) and African (3.2%). NF1 and BRAF mutations were associated with African ancestry, while TP53 and PIK3CA mutations were inversely correlated with Native American ancestry. Our study suggests that Brazilian CRC patients exhibit a mutation profile similar to other populations and identify the most frequently mutated genes, which could be useful in future target therapies and molecular cancer screening strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-49611-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6757044PMC
September 2019

Mutational profile of Brazilian lung adenocarcinoma unveils association of EGFR mutations with high Asian ancestry and independent prognostic role of KRAS mutations.

Sci Rep 2019 03 1;9(1):3209. Epub 2019 Mar 1.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil.

Lung cancer is the deadliest cancer worldwide. The mutational frequency of EGFR and KRAS genes in lung adenocarcinoma varies worldwide per ethnicity and smoking. The impact of EGFR and KRAS mutations in Brazilian lung cancer remains poorly explored. Thus, we investigated the frequency of EGFR and KRAS mutations in a large Brazilian series of lung adenocarcinoma together with patients' genetic ancestry, clinicopathological and sociodemographic characteristics. The mutational frequency of EGFR was 22.7% and KRAS was 20.4%. The average ancestry proportions were 73.1% for EUR, 13.1% for AFR, 6.5% for AME and 7.3% for ASN. EGFR mutations were independently associated with never-smokers, high-Asian ancestry, and better performance status. KRAS mutations were independently associated with tobacco exposure and non-Asian ancestry. EGFR-exon 20 mutations were associated with worse outcome. The Cox regression model indicated a worse outcome for patients whose were older at diagnosis (>61 y), solid histological subtype, loss of weight (>10%), worse performance status (≥2), and presence of KRAS mutations and EGFR mutational status in TKi non-treated patients. In conclusion, we assessed the clinicopathological and ethnic impact of EGFR and KRAS mutations in the largest series reported of Brazilian lung adenocarcinomas. These findings can support future clinical strategies for Brazilian lung cancer patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-39965-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6397232PMC
March 2019

Relationship between , inflammatory mediators and microRNAs in colorectal carcinogenesis.

World J Gastroenterol 2018 Dec;24(47):5351-5365

Department of Biology, UNESP, Univ. Estadual Paulista, Campus of São José do Rio Preto, São José do Rio Preto, São Paulo 15054-000, Brazil.

Aim: To examine the effect of () on the microenvironment of colonic neoplasms and the expression of inflammatory mediators and microRNAs (miRNAs).

Methods: Levels of DNA, cytokine gene mRNA (, , , , , and ), and potentially interacting miRNAs (miR-21-3p, miR-22-3p, miR-28-5p, miR-34a-5p, miR-135b-5p) were measured by quantitative polymerase chain reaction (qPCR) TaqMan assays in DNA and/or RNA extracted from the disease and adjacent normal fresh tissues of 27 colorectal adenoma (CRA) and 43 colorectal cancer (CRC) patients. mutations were detected by direct sequencing and microsatellite instability (MSI) status by multiplex PCR. Cytoscape v3.1.1 was used to construct the postulated miRNA:mRNA interaction network.

Results: Overabundance of in neoplastic tissue compared to matched normal tissue was detected in CRA (51.8%) and more markedly in CRC (72.1%). We observed significantly greater expression of , , , and miR-135b in CRA lesions and , , , , miR-34a and miR-135b in CRC tumours compared to their respective normal tissues. Only two transcripts for miR-22 and miR-28 were exclusively downregulated in CRC tumour samples. The mRNA expression of , , and miR-22 was positively correlated with quantification in CRC tumours. The mRNA expression of miR-135b and was inversely correlated. The miRNA:mRNA interaction network suggested that the upregulation of miR-34a in CRC proceeds a /-dependent response to . Finally, mutations were more frequently observed in CRC samples infected with and were associated with greater expression of miR-21 in CRA, while was upregulated in MSI-high CRC.

Conclusion: Our findings indicate that is a risk factor for CRC by increasing the expression of inflammatory mediators through a possible miRNA-mediated activation of /.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3748/wjg.v24.i47.5351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6305535PMC
December 2018

Screening and characterization of BRCA2 c.156_157insAlu in Brazil: Results from 1380 individuals from the South and Southeast.

Cancer Genet 2018 12 6;228-229:93-97. Epub 2018 Oct 6.

Molecular Oncology Research Center, Barretos Cancer Hospital, R. Antenor Duarte Villela, 1331. Barretos 14784-400, São Paulo, Brazil; Barretos School of Health Science, Dr. Paulo Prata. Av. Loja Maçonica Renovadora, 68. Barretos 14785-002, São Paulo, Brazil. Electronic address:

Portuguese immigration to Brazil occurred in several waves and greatly contributed to the genetic composition of current Brazilian population. In this study, we evaluated the frequency of a Portuguese founder Alu insertion in BRCA2 exon 3 (c.156_157insAlu) among individuals fulfilling Hereditary Breast and Ovarian Cancer (HBOC) syndrome criteria in 1,380 unrelated families originated from three distinct Brazilian States. We identified the c.156_157insAlu BRCA2 mutation in nine (9/1,380; 0.65%) probands analised. In carrier probands, European ancestry had the highest proportion (80%), followed by the African (10%) and Amerindian and in most families with the rearrangement, haplotype analyses were compatible with the Portuguese ancestral haplotype. In conclusion, the present study reports a low albeit relevant frequency of the Portuguese BRCA2 founder mutation c.156_157insAlu in Brazilian patients at-risk for HBOC Brazilian population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cancergen.2018.09.001DOI Listing
December 2018

Advantage of (T17) marker inclusion for microsatellite instability (MSI) detection in colorectal cancer patients.

Oncotarget 2018 Jun 19;9(47):28691-28701. Epub 2018 Jun 19.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, São Paulo, Brazil.

Colorectal cancer (CRC) is a leading cause of cancer death worldwide. Microsatellite instability (MSI) is a genetic pathway leading to CRC, associated with particular clinicopathological features, and recently a major biomarker of immunotherapy response. There is little information the frequency MSI among Brazilian CRC patients, and it is still debatable the ideal methodology for MSI screening in countries with limited resources. We proposed to evaluate MSI by molecular and immunohistochemistry (IHC) methods, to compare both methodologies and also to assess the inclusion of a novel microsatellite marker, (T17). The molecular MSI evaluation was performed using a PCR-multiplex panel in a total of 1013 CRC patients. Mismatch repair (MMR) proteins (MLH1, MSH2, MSH6 and PMS2) expression were evaluated by IHC. (T17) marker was analyzed by fragment analysis. Molecularly, 89.5% of cases were MSI-negative and 10.5% were MSI-positive. The IHC showed that 88.9% of cases exhibited MMR-proficient status, 10.2% were MMR-deficient and 0.9% was inconclusive. Genotyping of the (T17) in 106 MSI-positive and 215 MSI-negative cases showed its alteration only among the MSI-positive cases. We observed agreement (0.956, Kappa Test) between both molecular and IHC methodologies, with only eight discordant results, and in this subset of cases the (T17) corroborate the molecular findings. This study suggests the use of molecular assays over IHC for MSI analysis and proposes the inclusion (T17) marker as a complementary analysis in discordant cases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.25611DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6033349PMC
June 2018

Presence of microsatellite instability in esophageal squamous cell carcinoma associated with chagasic megaesophagus.

Biomark Med 2018 06 6;12(6):573-582. Epub 2018 Jun 6.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, São Paulo, Brazil.

Aim: The molecular pathogenesis of esophageal squamous cell carcinoma (ESCC) has been increasingly studied, but there is no report on the role of MSI in ESCC development associated with chagasic megaesophagus (CM).Results/methodology: In four ESCC/CM (4/19) we found microsatellite instability (MSI) alterations (21.1%), being three MSI-L (15.8%) and one MSI-H (5.3%). Four out of 35 ESCC cases showed MSI-L (11.4%) and only one out of 26 CM cases presented MSI-L (3.9%). The MSI-H was observed in an ESCC/CM patient that presents lack of MSH6 immunostaining corroborating deficiency in MMR pathway. Interestingly, the MSI-H ESCC/CM case also presented a deletion the HSP110 poly(T)17 gene.

Discussion/conclusion: Taking together, we concluded that MSI is a rare event in esophageal squamous cell carcinoma, but can be associated with CM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2217/bmm-2017-0329DOI Listing
June 2018

Vemurafenib resistance increases melanoma invasiveness and modulates the tumor microenvironment by MMP-2 upregulation.

Pharmacol Res 2016 09 18;111:523-533. Epub 2016 Jul 18.

Department of Clinical Chemistry & Toxicology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil. Electronic address:

The BRAF(V600E) mutation confers constitutive kinase activity and accounts for >90% of BRAF mutations in melanoma. This genetic alteration is a current therapeutic target; however, the antitumorigenic effects of the BRAF(V600E) inhibitor vemurafenib are short-lived and the majority of patients present tumor relapse in a short period after treatment. Characterization of vemurafenib resistance has been essential to the efficacy of next generation therapeutic strategies. Herein, we found that acute BRAF inhibition induced a decrease in active MMP-2, MT1-MMP and MMP-9, but did not modulate the metalloproteinase inhibitors TIMP-2 or RECK in naïve melanoma cells. In vemurafenib-resistant melanoma cells, we observed a lower growth rate and an increase in EGFR phosphorylation followed by the recovery of active MMP-2 expression, a mediator of cancer metastasis. Furthermore, we found a different profile of MMP inhibitor expression, characterized by TIMP-2 downregulation and RECK upregulation. In a 3D spheroid model, the invasion index of vemurafenib-resistant melanoma cells was more evident than in its non-resistant counterpart. We confirmed this pattern in a matrigel invasion assay and demonstrated that use of a matrix metalloproteinase inhibitor reduced the invasion of vemurafenib resistant melanoma cells but not drug naïve cells. Moreover, we did not observe a delimited group of cells invading the dermis in vemurafenib-resistant melanoma cells present in a reconstructed skin model. The same MMP-2 and RECK upregulation profile was found in this 3D skin model containing vemurafenib-resistant melanoma cells. Acute vemurafenib treatment induces the disorganization of collagen fibers and consequently, extracellular matrix remodeling, with this pattern observed even after the acquisition of resistance. Altogether, our data suggest that resistance to vemurafenib induces significant changes in the tumor microenvironment mainly by MMP-2 upregulation, with a corresponding increase in cell invasiveness.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.phrs.2016.07.017DOI Listing
September 2016

Molecular Profiling of a Rare Rosette-Forming Glioneuronal Tumor Arising in the Spinal Cord.

PLoS One 2015 15;10(9):e0137690. Epub 2015 Sep 15.

Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, SP, Brazil; Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; 3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.

Rosette-forming glioneuronal tumor (RGNT) of the IV ventricle is a rare and recently recognized brain tumor entity. It is histologically composed by two distinct features: a glial component, resembling pilocytic astrocytoma, and a component forming neurocytic rosettes and/or perivascular rosettes. Herein, we describe a 33-year-old man with RGNT arising in the spinal cord. Following an immunohistochemistry validation, we further performed an extensive genomic analysis, using array-CGH (aCGH), whole exome and cancer-related hotspot sequencing, in order to better understand its underlying biology. We observed the loss of 1p and gain of 1q, as well as gain of the whole chromosomes 7, 9 and 16. Local amplifications in 9q34.2 and 19p13.3 (encompassing the gene SBNO2) were identified. Moreover, we observed focal gains/losses in several chromosomes. Additionally, on chromosome 7, we identified the presence of the KIAA1549:BRAF gene fusion, which was further validated by RT-PCR and FISH. Across all mutational analyses, we detected and validated the somatic mutations of the genes MLL2, CNNM3, PCDHGC4 and SCN1A. Our comprehensive molecular profiling of this RGNT suggests that MAPK pathway and methylome changes, driven by KIAA1549:BRAF fusion and MLL2 mutation, respectively, could be associated with the development of this rare tumor entity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0137690PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570813PMC
May 2016
-->