Matrix metalloproteinases 7, 8, 12, 13 gene haplotypes associated with colorectal cancer in a Mexican population.

BACKGROUND: Matrix metalloproteinases (MMPs) are involved in tumor invasion and progression in colorectal cancer (CRC). Variants rs11568818, rs11225395, rs2276109 and rs2252070 have been associated with this neoplasm. OBJECTIVE: To evaluate MMPs 7, 8, 12, and 13 haplotypes and their association with CRC. MATERIAL AND METHODS: One-hundred and four patients and 112 healthy individuals were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP). For the association analysis, odds ratio and confidence interval values were calculated. Haplotype and linkage disequilibrium (LD) analysis was performed with Arlequin software, v3.5. RESULTS: LD was present between rs2276109 and rs2252070. Haplotypes rs11568818(A)-rs11225395(T)-rs2276109(A)-rs2252070(A) and rs11568818(A)-rs11225395(C)-rs2276109(A)-rs2252070(G) were associated with CRC risk, and haplotypes rs11568818(G)-rs11225395(C)-rs2276109(A)-rs2252070(A) and rs11568818(A)-rs11225395(T)-rs2276109(A)-rs2252070(G), with protection. CONCLUSION: Variants rs2276109 and rs2252070 showed genetic linkage. Two haplotypes were associated with the development of CRC (ATAA and ACAG) and two were associated with protection (GCAA and ATAG). This study represents the first report on variants rs11225395 and rs2276109 frequency in a Mexican population.

ANTECEDENTES: Las metaloproteinasas (MMP) se involucran en invasión y progresión tumoral en cáncer colorrectal (CCR). Las variantes rs11568818, rs11225395, rs2276109 y rs2252070 se han asociado con esta neoplasia. OBJETIVO: Evaluar haplotipos de las MMP 7, 8, 12, y 13 y su asociación con CCR. MATERIAL Y MÉTODOS: Se genotipificaron 104 pacientes y 112 individuos sanos mediante reacción en cadena de la polimerasa con análisis del polimorfismo de los fragmentos de restricción (PCR-RFLP). Para el análisis de asociación fueron calculados valores de odds ratio e intervalo de confianza. El análisis de haplotipos y desequilibrio de ligamiento (LD) se realizó con el software Arlequin v3.5. RESULTADOS: Se presentó LD entre rs2276109 y rs2252070. Los haplotipos rs11568818(A)-rs11225395(T)-rs2276109(A)-rs2252070(A) y rs11568818(A)-rs11225395(C)-rs2276109(A)-rs2252070(G) se asociaron con riesgo de CCR y los haplotipos rs11568818(G)-rs11225395(C)-rs2276109(A)-rs2252070(A) y rs11568818(A)-rs11225395(T)-rs2276109(A)-rs2252070(G) con protección. CONCLUSIÓN: Las variantes rs2276109 y rs2252070 mostraron ligamiento génico. Dos haplotipos fueron asociados con el desarrollo de CCR (ATAA y ACAG) y dos fueron asociados con protección (GCAA y ATAG). Este estudio representa el primer reporte de frecuencias de las variantes rs11225395 y rs2276109 en población mexicana.

High frequency of MLH1 promoter methylation mediated by gender and age in colorectal tumors from Mexican patients.

INTRODUCTION: Several genes determine the development of colorectal cancer (CRC), such as MLH1, which encodes a protein that participates in DNA repair. MLH1 hypermethylation has been associated with gene silencing. OBJECTIVE: To analyze the methylation of five regions of MLH1 CpG island in colorectal tumors from Mexican patients. MATERIALS AND METHODS: One hundred and one tumor tissue samples were obtained from Mexican patients with CRC who provided informed consent. DNA was subjected to bisulfite conversion. Methylation of all five regions of the CpG island was evaluated using methylation-specific PCR. RESULTS: The frequency of methylation in Mexican patients with CRC was 25%. Regions A and B methylation was the main observed pattern (60%). Female patients showed a higher frequency of methylation (71%; OR 3.085; CI: 1.85-8.03; p = 0.02), and out of total methylated samples, 80% corresponded to individuals older than 45 years (p < 0.05). CONCLUSION: We calculated a methylation frequency for the MLH1 gene of 25% in Mexican patients with CRC, with this being the first report for this population. Female patients and patients older than 45 years showed a higher frequency of methylation.

INTRODUCCIÓN: Varios genes determinan el desarrollo de cáncer colorrectal (CCR), como MLH1, el cual codifica una proteína que participa en la reparación del ADN. La hipermetilación de MLH1 ha sido asociado con silenciamiento génico. OBJETIVO: Analizar la metilación de cinco regiones de la isla CpG de MLH1 en tumores colorrectales de pacientes mexicanos. MATERIALES Y MÉTODOS: Se obtuvieron 101 muestras de tejido tumoral de pacientes mexicanos con CCR, quienes proporcionaron su consentimiento informado. El ADN fue sometido a conversión por bisulfito. La metilación de las cinco regiones de la isla CpG fue evaluada utilizando PCR específica para metilación. RESULTADOS: La frecuencia de metilación en pacientes mexicanos con CCR fue del 25%. La metilación de las regiones A y B fue el principal patrón observado (60%). Las pacientes de sexo femenino mostraron una mayor frecuencia de metilación (71%) (odds ratio: 3.085; intervalo de confianza; 1.85-8.03; p = 0.02); y del total de muestras metiladas, el 80% fueron individuos mayores de 45 años (p < 0.05). CONCLUSIÓN: Calculamos una frecuencia de metilación para el gen MLH1 del 25% en pacientes mexicanos con CCR, siendo el primer reporte para esta población. Pacientes de sexo femenino y pacientes mayores de 45 años mostraron una mayor frecuencia de metilación.

Somatic deletion of KDM1A/LSD1 gene is associated to advanced colorectal cancer stages.

AIMS: KDM1A/LSD1 and ZNF217 are involved in a protein complex that participates in transcriptional regulation. ZNF217 has been analysed in numerous cancers and its amplification has been associated with advanced stages of disease; however, a similar role for KDM1A/LSD1 has not been uncovered. In this study, we estimated the number of KDM1A/LSD1 and ZNF217 gene copies in tissue samples from patients diagnosed with colorectal cancer (CRC), as well as its association with clinicopathological features in patients with CRC. METHODS: Paraffin-embedded tumour samples from 50 patients with CRC with a histopathological diagnosis of CRC were included. The number of copies of KDM1A/LSD1 and ZNF217 genes was determined by fluorescence in situ hybridisation (FISH). We also analysed the association between copy numbers of selected genes and clinicopathological data based on multivariate analysis. RESULTS: Deletion of the KDM1A/LSD1 gene occurred in 19 samples (38%), whereas ZNF217 gene amplification was identified in 11 samples (22%). We found a significant association between lymph node metastasis or advanced tumour stage and KDM1A/LSD1 gene deletion (p value=0.0003 and p value=0.011, respectively). CONCLUSIONS: KDM1A/LSD1 gene deletion could be considered a novel prognostic biomarker of late-stage CRC.