RESUMO
BACKGROUND: The collagen11A1 (COL11A1) gene is overexpressed in pancreatic cancer. The expression of COL11A1 protein could be involved in desmoplastic events in pancreatic cancer, but an antibody that specifically stains the COL11A1 protein is not currently available. METHODS AND FINDINGS: A total of 54 pancreatic ductal adenocarcinomas (PDAC), 23 chronic pancreatitis (CP) samples, and cultured peritumoral stromal cells of PDAC (passages 3-6) were studied. Normal human pancreas tissue samples were obtained through a cadaveric organ donation program. 1) Validation of COL11A1 gene overexpression by q-RT-PCR. FINDINGS: the expression of COL11A1 gene is significantly increased in PDAC samples vs. normal and CP samples. 2) Analysis of COL11A1 by immunohistochemistry using highly specific anti-proCOL11A1 antibodies. FINDINGS: anti-proCOL11A1 stains stromal cells/cancer-associated fibroblasts (CAFs) of PDAC but it does not stain chronic benign condition (chronic pancreatitis) stromal cells, epithelial cells, or normal fibroblasts. 3) Evaluation of the discrimination ability of the antibody. FINDINGS: anti-proCOL11A1 immunostaining accurately discriminates between PDAC and CP (AUC 0.936, 95% CI 0.851, 0.981). 4) Phenotypic characterization of proCOL11A1+ stromal cells co-staining with mesenchymal, epithelial and stellate cell markers on pancreatic tissue samples and cultured peritumoral pancreatic cancer stromal cells. FINDINGS: ProCOL11A1+ cells present co-staining with mesenchymal, stellate and epithelial markers (EMT phenotype) in different proportions. CONCLUSIONS/SIGNIFICANCE: Detection of proCOL11A1 through immunostaining with this newly-developed antibody allows for a highly accurate distinction between PDAC and CP. Unlike other available antibodies commonly used to detect CAFs, anti-proCOL11A1 is negative in stromal cells of the normal pancreas and almost absent in benign inflammation. These results strongly suggest that proCOL11A1 is a specific marker for CAFs, and thus, anti-proCOL11A1 is a powerful new tool for cancer research and clinical diagnostics.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Colágeno Tipo XI/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pancreáticas/metabolismo , Células Estromais/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Área Sob a Curva , Colágeno Tipo XI/imunologia , Primers do DNA/genética , Humanos , Imuno-Histoquímica , Camundongos , Microscopia de Fluorescência , Curva ROC , Reação em Cadeia da Polimerase em Tempo RealRESUMO
AIM: Pharmacogenetic studies in breast cancer (BC) may predict the efficacy of tamoxifen and the toxicity of paclitaxel and capecitabine. We determined the frequency of polymorphisms in the CYP2D6 gene associated with activation of tamoxifen, and those of the genes CYP2C8, CYP3A5 and DPYD associated with toxicity of paclitaxel and capecitabine. We also included a IL-10 gene polymorphism associated with advanced tumor stage at diagnosis. PATIENTS & METHODS: Genomic DNAs from 241 BC patients from northeast Mexico were genotyped using DNA microarray technology. RESULTS: For tamoxifen processing, CYP2D6 genotyping predicted that 90.8% of patients were normal metabolizers, 4.2% ultrarapid, 2.1% intermediate and 2.9% poor metabolizers. For paclitaxel and the CYP2C8 gene, 75.3% were normal, 23.4% intermediate and 1.3% poor metabolizers. Regarding the DPYD gene, only one patient was a poor metabolizer. For the IL-10 gene, 47.1% were poor metabolizers. CONCLUSION: These results contribute valuable information towards personalizing BC chemotherapy in Mexican women.
Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Neoplasias da Mama/genética , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP3A/genética , Interleucina-10/genética , Polimorfismo Genético/genética , Adulto , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Capecitabina , Citocromo P-450 CYP2C8 , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Genótipo , Humanos , México , Pessoa de Meia-Idade , Paclitaxel/uso terapêutico , Espanha , Tamoxifeno/uso terapêuticoRESUMO
A novel IgG1, κ mouse monoclonal antibody (clone 1E8.33) to human procollagen 11A1 has been generated. This antibody is poorly mutated, essentially in germ line configuration; its complementarity determining regions (CDRs) are especially rich in tyrosine and serine residues. The epitope recognized is encompassed in the YNYGTMESYQTEAPR amino acid stretch within the variable region of human procollagen 11A1. Human procollagens 5A1 and 11A1 are very similar. However, this antibody does not cross-react with human procollagen 5A1. In human breast tumors, only the activated peritumoral myofibroblasts show a strong intracytoplasmic staining with this antibody. As procollagen 11A1 is overexpressed in the stroma of human tumors with desmoplastic reaction, this antibody represents a valuable tool for diagnostic purposes.