ABSTRACT
BACKGROUND: Vascular endothelial growth factor (VEGF), a major mediator of vascular permeability and angiogenesis, may play a pivotal role in mediating the development and progression of breast cancer. In the present study, we examined the genetic variations of the VEGF gene to assess its possible relation to breast cancer. MATERIALS AND METHODS: A total of 200 patients with histologically confirmed cases of breast cancer and 200 healthy women were genotyped for VEGF single nucleotide polymorphisms (405G > C and −1154G > A) by polymerase chain reaction‑restriction fragment length polymorphism analysis. Pre‑operative plasma VEGF levels were determined by enzyme‑linked immunosorbent assay in 200 women with breast cancer and in 200 normal female controls. RESULTS: The genotype frequencies of the +405G > C, −1154G > A polymorphisms did not show a significant deviation from the Hardy‑Weinberg expectation. The minor allele frequencies of the +405G > C and −1154G > A polymorphisms among cases and controls were 33.5% (C allele), 31.5% (A allele) and 35% (C allele), 34.5% (A allele) respectively. +405GG and −1154GG genotypes were associated with higher levels of VEGF among breast cancer cases and controls. Increased plasma VEGF levels were significantly associated with, clinical stage of the disease (P = 0.035). CONCLUSION: Although none of the polymorphisms were significantly associated with breast cancer, some of the VEGF genotypes may influence tumor growth through an altered expression of VEGF and tumor angiogenesis.
ABSTRACT
Introduction: Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and is involved in DNA synthesis, DNA repair and DNA methylation. Genetic polymorphisms of this enzyme have been shown to impact several diseases, including cancer. Leukemias are malignancies arising from rapidly proliferating hematopoietic cells having great requirement of DNA synthesis. This case-control study was undertaken to analyze the association of the MTHFR gene polymorphisms 677 C"T and 1298 A"C and the risk of acute lymphoblastic leukemia in children. Materials and Methods: Eighty-six patients aged below 15 years with a confirmed diagnosis of acute lymphoblastic leukemia (ALL) and 99 matched controls were taken for this study. Analysis of the polymorphisms was done using the polymerase chain reaction -restriction fragment length polymorphism (PCR-RFLP) method. Results: Frequency of MTHFR 677 CC and CT were 85.9% and 14.1% in the controls, and 84.9% and 15.1% in the cases. The 'T' allele frequency was 7% and 7.5% in cases and controls respectively. The frequency of MTHFR 1298 AA, AC, and CC were 28.3%, 55.6% and 16.1% for controls and 23.3%, 59.3% and 17.4% for cases respectively. The 'C' allele frequency for 1298 A→C was 43.9% and 47% respectively for controls and cases. The odds ratio (OR) for C677T was 1.08 (95% CI 0.48- 2.45, p = 0.851) and OR for A1298C was 1.29(95% CI 0.65-2.29, p = 0.46) and OR for 1298 CC was 1.31 (95% CI 0.53-3.26, p =0.56). The OR for the combined heterozygous status (677 CT and 1298 AC) was 1.94 (95% CI 0.58 -6.52, p = 0.286). Conclusion: The prevalence of 'T' allele for 677 MTHFR polymorphism was low in the population studied. There was no association between MTHFR 677 C→T and 1298 A→C gene polymorphisms and risk of ALL, which may be due to the small sample size.