Involvement of transforming growth factor beta-1 (TGFβ1) cytokine and FOXP3 transcription factor genetic polymorphisms in hematological malignancies

Hematological malignancies (HM) are a group of neoplastic diseases that arise from hematologic cell lineages. Transforming growth factor beta 1 (TGFβ1) is shown to negatively regulate normal and malignant hematopoiesis and, in immunological context, to promote T cell exhaustion and generation of regulatory T cells, which are shown to be deleterious in cancer, by the induction of transcription factor FOXP3 expression. The present study aimed to evaluate TGFB1 exon-1 rs1800470 and FOXP3 intron-1 rs2232365 polymorphisms in relation to HM susceptibility. DNA was extracted from blood samples of 43 HM patients and 142 neoplasia-free individuals and polymorphisms were analyzed by allelic-specific PCR. Association analysis was assessed by the Odds Ratio (OR) with significance level of 5%. Regarding FOXP3 polymorphism, no significant differences were observed in genotype or allele distribution among the patients and controls. However, there was a positive association between TGFB1 TT genotype and HM susceptibility (OR = 4.07; CI95% = 1.94 - 8.52). In the combined analysis, a positive association was also observed for TGFB1 TT and FOXP3 GG genotypes (OR = 4.00; CI95% = 1.54 - 10.41) in relation to HM susceptibility. Our results indicated promising new markers to be further investigated in hematological malignancies.

Protein Expression and Codon 72 Polymorphism of TP53 Gene in Triple Negative Breast Cancer

A subgroup of tumor that has received attention is triple-negative breast cancer (TNBC), which presents phenotype of negative estrogen receptor, negative progesterone receptor and has no overexpression of HER2. TP53 acts as a tumor suppressor limiting the proliferation of damaged cells. A polymorphic site (rs1042522) of TP53 encodes either an arginine or a proline amino acid, but its biological significance remains unclear. This study aimed to investigate this variant and its expression in search for a possible involvement in TNBC susceptibility and clinical outcome. Genetic polymorphism was evaluated in 50 patients and 115 controls by PCR based methodology and immunohistochemistry was done with monoclonal antibody. Case-control study showed no positive or negative association (OR= 0.95; CI95%= 0.48-1.89). Comparison of genotypes and clinical outcome showed no significant results. Despite most of patients presented p53 positive staining by immunohistochemistry, there was no significant association in relation to prognostic parameters. Results demonstrated a lack of association between codon 72 polymorphism, susceptibility and prognosis of TNBC. Immunohistochemistry analysis should be done more carefully, since most of the patients had the somatic mutation of p53, which could be an indicator of prognostic value in TNBC.