Association between genetic polymorphisms in DNA mismatch repair-related genes with risk and prognosis of head and neck squamous cell carcinoma.

We examined the influence of MLH1 c.-93G>A, MSH2 c.211 + 9C>G, MSH3 c.3133G>A and EXO1 c.1765G>A polymorphisms, involved in DNA mismatch repair (MMR), on head and neck (HN) squamous cell carcinoma (SCC) risk and prognosis. Aiming to identify genotypes, DNA from 450 HNSCC patients and 450 controls was analyzed by PCR-RFLP or real time PCR. MSH2 GG plus MSH3 GG (31.7% vs. 18.7%, p = 0.003) genotypes were higher in laryngeal SCC (LSCC) patients than in controls. Carriers of the respective combined genotype were under a 3.69 (95% CI: 1.54-8.81)-fold increased risk of LSCC. Interactions of tobacco and tobacco plus all the above-mentioned polymorphisms on HNSCC and LSCC risk were also evident in study (p = 0.001). At 60 months of follow-up, relapse-free survival (RFS) was shorter in patients with EXO1 GG genotype (54.8% vs. 61.1%, p = 0.03) and overall survival (OS) was shorter in patients with MSH3 GG genotype (42.8% vs. 52.5%, p = 0.02) compared to those with other genotypes, respectively. After multivariate Cox analysis, patients with EXO1 GG and MSH3 GG genotypes had worst RFS (HR: 1.50, 95% CI: 1.03-2.20, p = 0.03) and OS (HR: 1.59, 95% CI: 1.19-2.13, P = 0.002) than those with the remaining genotypes, respectively. Our data present, for the first time, evidence that inherited MLH1 c.-93G>A, MSH2 c.211 + 9C>G, MSH3 c.3133G>A, and EXO1 c.1765G>A abnormalities of DNA MMR pathway are important determinants of HNSCC, particularly among smokers, and predictors of patient outcomes.

Valproic acid influences the expression of genes implicated with hyperglycaemia-induced complement and coagulation pathways.

Because the liver plays a major role in metabolic homeostasis and secretion of clotting factors and inflammatory innate immune proteins, there is interest in understanding the mechanisms of hepatic cell activation under hyperglycaemia and whether this can be attenuated pharmacologically. We have previously shown that hyperglycaemia stimulates major changes in chromatin organization and metabolism in hepatocytes, and that the histone deacetylase inhibitor valproic acid (VPA) is able to reverse some of these metabolic changes. In this study, we have used RNA-sequencing (RNA-seq) to investigate how VPA influences gene expression in hepatocytes. Interesting, we observed that VPA attenuates hyperglycaemia-induced activation of complement and coagulation cascade genes. We also observe that many of the gene activation events coincide with changes to histone acetylation at the promoter of these genes indicating that epigenetic regulation is involved in VPA action.

Association of CYP1A1 A4889G and T6235C polymorphisms with the risk of sporadic breast cancer in Brazilian women.

OBJECTIVES: We examined the influence of CYP1A1 A4889G and T6235C polymorphisms on the risk of sporadic breast cancer. METHODS: DNA from 742 sporadic breast cancer patients and 742 controls was analyzed using the polymerase chain reaction, followed by the restriction fragment length polymorphism technique. RESULTS: More patients had the CYP1A1 4889AG+GG genotype compared to controls (29.0% versus 23.2%, p=0.004). The G allele carriers had a 1.50-fold increased risk (95% CI: 1.14-1.97) of sporadic breast cancer compared to the other study participants. The frequency of the 4889AG+GG genotype among the Caucasian patients was higher than in the non-Caucasian patients (30.4% versus 20.2%, p=0.03) and controls (30.4% versus 23.2%, p=0.002). Caucasians and G allele carriers had a 1.61-fold increased risk (95% CI: 1.20-2.15) of sporadic breast cancer compared to other subjects. The CYP1A1 4889AG+GG genotype was more common among patients with a younger median age at first full-term pregnancy than among controls (33.8% versus 23.2%, p=0.001) and subjects whose first full-term pregnancies occurred at an older age (33.8% versus 26.1%, p=0.03). Women with the CYP1A1 4889AG+GG genotype and earlier first full-term pregnancies had a 1.87-fold (95% CI: 1.32-2.67) increased risk of sporadic breast cancer compared to the other study participants. Excess CYP1A1 4889AG+GG (39.8% versus27.1%, p=0.01) and 6235TC+CC (48.4% versus 35.9%, p=0.02) genotypes were also observed in patients with grade I and II tumors compared to patients with grade III tumors and controls (39.8% versus 23.2%, p=0.04; 48.4% versus 38.6%, p=0.04). The G and C allele carriers had a 2.44-fold (95% CI: 1.48-4.02) and 1.67-fold (95% CI: 1.03-2.69) increased risk, respectively, of developing grade I and II tumors compared to other subjects. CONCLUSIONS: The CYP1A1 A4889G and T6235C polymorphisms may alter the risk of sporadic breast cancer in Brazilian women.

Clinical effects of A4889G and T6235C polymorphisms in cytochrome P-450 CYP1A1 for breast cancer patients treated with tamoxifen: implications for tumor aggressiveness and patient survival.

PURPOSE: Individual differences in cytochrome P-450 efficiency partly explain their variations in resistance to tamoxifen and estrogen metabolism. Two polymorphisms of the CYP1A1 gene-A4889G and T6235C-are known to affect activation of estrone and estradiol and to deregulate concentration of highly active tamoxifen metabolites. However, the clinicopathologic implications of these findings have not yet been evaluated. OBJECTIVE: The objective of this study is to evaluate whether T6235C and A4889G gene polymorphisms are related to pathological presentations and clinical outcomes of ER+/PR+ breast cancer (BC) in women using tamoxifen. METHODS: We included 405 women with ER+/PR+ tumors, who used tamoxifen as their primary therapy, and for whom 5-year follow-up data were available. We evaluated associations within clinicopathologic features, including overall 5-year survival, with CYP1A1 gene status. RESULTS: Univariate analysis showed that a slightly higher proportion of women with AG/GG genotypes were of European descent (P = 0.05) and that TC/CC genotype was significantly associated with premenopausal status (P = 0.01); however, no significant association remained after multivariate adjustment. Women with CYP1A1 genotypes other than AA and TT were more prone to develop low-grade tumors; 85.9 % of tumors in AA and TT genotype groups were grade III, but only 76.1 % of tumors in carriers of the polymorphisms were grade III (adjusted P = 0.02; OR 0.51 for grade III disease; 95 % CI 0.28-0.93). After 60 months of follow-up, ~75 % of the women were alive. There was no significant difference in survival related to the CYP1A1 gene status. CONCLUSIONS: Breast cancer patients carrying CYP1A1 gene polymorphisms developed less aggressive tumors, but showed no evidence of better prognoses.

Association of CYP1A1 A4889G and T6235C polymorphisms with the risk of sporadic breast cancer in Brazilian women

OBJECTIVES:We examined the influence of CYP1A1 A4889G and T6235C polymorphisms on the risk of sporadic breast cancer.METHODS:DNA from 742 sporadic breast cancer patients and 742 controls was analyzed using the polymerase chain reaction, followed by the restriction fragment length polymorphism technique.RESULTS:More patients had the CYP1A1 4889AG+GG genotype compared to controls (29.0% versus 23.2%, p=0.004). The G allele carriers had a 1.50-fold increased risk (95% CI: 1.14-1.97) of sporadic breast cancer compared to the other study participants. The frequency of the 4889AG+GG genotype among the Caucasian patients was higher than in the non-Caucasian patients (30.4% versus 20.2%, p=0.03) and controls (30.4% versus 23.2%, p=0.002). Caucasians and G allele carriers had a 1.61-fold increased risk (95% CI: 1.20-2.15) of sporadic breast cancer compared to other subjects. The CYP1A1 4889AG+GG genotype was more common among patients with a younger median age at first full-term pregnancy than among controls (33.8% versus 23.2%, p=0.001) and subjects whose first full-term pregnancies occurred at an older age (33.8% versus 26.1%, p=0.03). Women with the CYP1A1 4889AG+GG genotype and earlier first full-term pregnancies had a 1.87-fold (95% CI: 1.32-2.67) increased risk of sporadic breast cancer compared to the other study participants. Excess CYP1A1 4889AG+GG (39.8% versus27.1%, p=0.01) and 6235TC+CC (48.4% versus 35.9%, p=0.02) genotypes were also observed in patients with grade I and II tumors compared to patients with grade III tumors and controls (39.8% versus 23.2%, p=0.04; 48.4% versus 38.6%, p=0.04). The G and C allele carriers had a 2.44-fold (95% CI: 1.48-4.02) and 1.67-fold (95% CI: 1.03-2.69) increased risk, respectively, of developing grade I and II tumors compared to other subjects.CONCLUSIONS:The CYP1A1 A4889G and T6235C polymorphisms may alter the risk of sporadic breast cancer in Brazilian women.