Perfil molecular de cáncer de endometrio en mujeres de Bogotá D.C., Colombia

Introducción: El cáncer de endometrio ocupa el sexto lugar en incidencia del cáncer en mujeres. La caracterización molecular de este cáncer permite optimizar la estratificación de riesgo para mejorar el tratamiento de las pacientes. Objetivo: Determinar el perfil molecular TCGA de pacientes con cáncer de endometrio en Bogotá, D.C., Colombia. Método: Estudio descriptivo en una cohorte de pacientes con cáncer de endometrio. Las mutaciones en los exones 9 a 14 del gen POLE fueron identificadas mediante amplificación por reacción en cadena de la polimerasa, seguida de secuenciación Sanger y análisis bioinformático. La expresión de las proteínas MMR y p53 se identificó mediante inmunohistoquímica. Resultados: Se incluyeron 40 pacientes con una mediana de edad de 66 años. El 15% presentaron mutaciones en el dominio exonucleasa de POLE. El 32% de las pacientes que no presentaron mutaciones manifestaron deficiencia en el sistema MMR. El 43,47% de las pacientes sin mutaciones en POLE ni alteración del sistema MMR presentaron alteración de la proteína p53. Conclusiones: La población de cáncer de endometrio analizada presenta un perfil molecular TCGA similar a lo reportado para otras poblaciones.

Introduction: Endometrial cancer ranks sixth in cancer incidence among women. Its molecular characterization allows for a more precise risk stratification with the aim of improving patient treatment. Objective: To determine the TCGA molecular profile of patients with endometrial cancer in Bogota, Colombia. Method: A descriptive study of a cohort of patients with endometrial cancer. The expression of MMR proteins and p53 was identified through immunohistochemistry. Mutations in exons 9 to 14 of the POLE gene were identified through polymerase chain reaction amplification, followed by Sanger sequencing and bioinformatic analysis. Results: Forty patients were included in the study, with a median age of 66 years, 15% of them exhibited mutations in the exonuclease domain of POLE, while 32% of patients without mutations showed deficiency in the MMR system. Forty three percent of patients without mutations in POLE or MMR alterations showed aberrant p53 protein expression. Conclusions: The analyzed population of endometrial cancer presents a TCGA molecular profile similar to that reported for other populations.

Single Nucleotide Variants in the TLR1, TLR2 and TLR6 Genes: A Case-Control Study in a Colombian Population.

BACKGROUND: Single nucleotide variants in toll-like receptor genes play a crucial role in leprosy susceptibility or resistance. METHODS: With an epidemiology case-control study, associations between SNVs rs5743618 in TLR1, rs5743708 in TLR2, and rs5743810 in TLR6 and overall susceptibility for leprosy were estimated in 114 cases and 456 controls. Following that, stratified analysis was performed. DNA was extracted from peripheral blood. Genotyping was performed using predesigned TaqMan probes. RESULTS: The A/G genotype of rs5743810 behaved as a protective factor for the development of leprosy in the codominant (OR= 0.37; 95% CI = 016-0.86, p = 0.049) and over-dominant (OR = 0.38; 95% CI = 0.16-0.88, p = 0.019) inheritance models. The A/G and A/A genotypes behaved as a protective factor (OR = 0.39; 95% CI = 0.17-0.87, p = 0.016) in the dominant model. The SNVs rs5743618 and rs5743708 showed no association with any of the models. The CGG haplotype (rs5743618-rs5743708-rs5743810) behaved as a susceptibility factor for developing leprosy (OR = 1.86; 95% CI = 1.11-3.10, p = 0.019). The latter haplotype behaved as a susceptibility factor for leprosy development in women (OR = 2.39; 95% CI = 1.21-4.82, p = 0.013). CONCLUSIONS: The identified variants in the genes encoding TLRs, specifically rs5743810 in TLR6 and CGG (rs5743618-rs5743708-rs5743810) haplotypes, may somehow explain leprosy susceptibility in the studied population in a leprosy endemic region in Colombia.

3'UTR-CDKN2A and CDK4 Germline Variants Are Associated With Susceptibility to Cutaneous Melanoma.

BACKGROUND/AIM: Genetic variations of the CDKN2A and CDK4 gene have been associated to melanoma development. In the present study we investigated the potential associations of CDKN2A and CDK4 gene variants in a colombian population diagnosed with melanoma. MATERIALS AND METHODS: DNA was extracted from whole blood samples from 85 patients diagnosed with cutaneous melanoma and 166 healthy controls. CDKN2A and CDK4 genes were genotyped using a high-resolution melting assay. RESULTS: A similar distribution of CDKN2A variants 500C>G and 540C>T was found among cases (12% and 31% respectively) and controls (15% and 31% respectively). The CDKN2A variants were present in 36% of acral lentiginous melanoma and 39.47% of lentigo maligna. The haplotype analysis showed an association with susceptibility in the development of melanoma. CONCLUSION: The presence of haplotype 500G/540C in males is associated with an increased risk of melanoma in a colombian population, especially in subjects with a family history of cancer.

CDKN2A Polymorphism in Melanoma Patients in Colombian Population: A Case-Control Study.

INTRODUCTION: Melanoma is the most aggressive type of skin cancer, with poor prognosis in advanced stages. The incidence and mortality rates have increased in recent years. Single nucleotide polymorphisms p.R24P, p.M53I, p.G101W, p.V126D, and p.A148T in the CDKN2A (HGNC ID: 1787) gene have been associated with the development of melanoma in different populations; however, this association has not been studied in Colombia. METHODS: Cutaneous melanoma patients and healthy controls (85 cases and 166 controls) were included in this study. These subjects were screened through HRM-qPCR assay and detected variants in exon 1 and 2 of CDKN2A gene and confirmed with Sanger sequencing. Chi-square test was used to compare allele and genotype distributions between cases and controls. Odds ratio (OR) with 95% confidence interval (CI) was calculated to determine the association between polymorphisms and haplotypes with melanoma susceptibility. Statistical and haplotype analyses were performed using Stata® and R-Studio®. RESULTS: Fifty-four percent of women were identified both in cases and controls. The frequencies of melanoma subtypes were 36,47% lentigo maligna, 24,71% acral lentiginous, 23,53% superficial extension, and 15,29% nodular. Variants in the CDKN2A gene were 11.76% in cases and 8.43% in controls. The most frequent was p.A148T in 5.88% of cases and in 4.82% of controls. GGTTG haplotype showed statistically significant differences between cases and controls (p value = 0.04). CONCLUSION: CDKN2A polymorphisms p.G101W, p.R24P, p.M53I, and A148T are not associated with melanoma susceptibility in the Colombian population; further studies regarding genetic interaction and additive effects between more variants are required.

Mutations in the BRAF, NRAS, and C-KIT Genes of Patients Diagnosed with Melanoma in Colombia Population.

INTRODUCTION: Mutations in the BRAF, NRAS, and C-KIT genes have been associated with the histopathological characteristics of melanoma. Likewise, the incidence of each of these subtypes changes according to the geographical origin of the population analyzed. OBJECTIVE: To determine the mutation frequency in exons 11 and 15 of the BRAF gene, exons 1 and 2 of the NRAS gene, and exons 11, 13, and 17 of the C-KIT gene and to relate it with histological subtypes in patients from a region with high levels of ultraviolet radiation. Methodology. The clinicopathological characteristics of 54 cutaneous melanoma samples were analyzed. Mutation analysis was performed via qPCR on paraffin-embedded tumor tissue samples using probes specific for the V600E mutation. Amplification of exons 11 and 15 of the BRAF gene, exons 1 and 2 of the NRAS gene, and exons 11, 13, and 17 of the C-KIT gene was performed for subsequent sequencing using the Sanger method. RESULT: The most frequent histological subtype in the analyzed sample was lentigo maligna/lentigo maligna melanoma (52%) followed by acral lentiginous melanoma (20%). The BRAF-V600 variant was the most frequent (63.6%). The most frequent (54%) mutation in NRAS was p.Lys5∗. In the C-KIT gene, only the Val560Ala mutation was found. CONCLUSION: Differences in histological subtypes and mutations in the BRAF, NRAS, and C-KIT genes were found in the analyzed population. This indicates that environmental and genetic factors significantly influence the introduction of the disease in this geographic region.

Isolation and phenotypic characterization of tumor cells of patients with a diagnosis of ovarian cancer.

Ovarian cancer is the fifth leading cause of cancer-related deaths. It causes approximately 125,000 deaths per year worldwide; its diagnosis is made in advanced stages resulting in a high mortality rate. The objective of the study was optimizing the isolation of cells obtained from the solid tumor and ascitic fluid of patients with ovarian cancer and the phenotype with markers related to the epithelial-mesenchymal transition. For this, the solid tumor tissue was disaggregated and cultivated with different methodologies. As a result, cell growth was obtained and epi-immunofluorescence was performed using antibodies against E-cadherin, EpCAM, N-cadherin, vimentin, CD133, and CD44. The primary culture from the solid tumor was obtained using Dispase II and DMEM/F12. Finally, heterogeneity was detected in terms of the expression of mesenchymal and epithelial type markers in the two types of isolated cells. Additionally, CD133 and CD44 expression was detected, proteins associated with the tumor stem cells phenotype.