TNF alpha promoter polymorphisms analysis in benign and malignant breast lesions

Section: Discussionsupporting

confidence: 84%

Association of single nucleotide polymorphisms (SNPs) in TNF-LTA locus with breast cancer risk in Indian population

Kohaar

Tiwari

Kumar

et al. 2008

“…A total of 16 studies (18 studies including the sub-studies) on TNF-a-308 polymorphism of [3,[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] and six studies on TNF-a-238 polymorphism (35 studies including the sub-studies) [3,14,20,22,23,26] that met the inclusion criteria were used to evaluate the relation of these two variants with risk for BC. The detailed characteristics of the studies were shown in Table 1.…”

Section: Resultsmentioning

confidence: 99%

TNF-alpha polymorphisms and breast cancer

Feng

et al. 2011

Tumor necrosis factor-α (TNF-α) is an important pro-inflammatory cytokine in the development and progress in human cancer. TNF-α polymorphisms have been confirmed to influence the risk for several types of cancer, however, the associations between TNF-α polymorphisms and breast cancer (BC) remain controversial and ambiguous. The aim of this meta-analysis is to explore more precise estimations regarding this point. Electronic searches of several databases were conducted for all online publications on the associations between TNF-α-238, -308, -857, -863, -1031, -1210 polymorphisms and BC through March 2011. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated to assess the strength of these associations in fixed- and random-effect models with Review manager 5.0. A total of 17 studies with 44,442 BC patients and 49,926 controls involved were identified. This meta-analysis showed no significant association between TNF-α-308 polymorphism and BC (AA + GA vs. GG: OR = 0.95, 95% CI = 0.82-1.09) in overall and (OR = 1.44, 95% CI = 0.61-3.40) Asian populations, however, a negative association was shown in Caucasian subgroup (OR = 0.91, 95% CI = 0.85-0.97). As regards the TNF-α-238 polymorphism, the OR values (95% CI) were 0.99 (0.94-1.05), 0.94 (0.78-1.14), and 1.00 (0.95-1.05) for the overall, Asian, and Caucasian studies, respectively. No significant associations were found for other polymorphisms. Furthermore, there was a coincidence in the sensitivity analysis of these associations. No publication bias was detected in this study. To sum up, no significant associations were found between the TNF-α-308, -238, -857, -863, -1031, -1210 polymorphisms and the risk for BC in overall populations, whereas a negative association was found between TNF-α-308 polymorphism and BC in Caucasian populations.

“…Majority of the studies till date reported lack of association between TNF-a (-308 G[A) polymorphism and breast cancer [5,[19][20][21][26][27][28][29][30][31][32][33][34][35]. For example, a study on the TNFa (-308 G[A) polymorphism in a Korean population comprising 95 breast cancer cases and 190 controls, showed no association [19].…”

Section: Discussionmentioning

confidence: 99%

Role of ethnic variations in TNF-α and TNF-β polymorphisms and risk of breast cancer in India

Singh

Francis²,

Bid

et al. 2010

TNF-α and -β, the multi-functional pro-inflammatory cytokines, are known to play important roles in both tumor progression and destruction based on their concentrations. Growth factors and various stimuli such as cytokines regulate proliferation of the breast epithelial cells. Therefore, the polymorphisms in the genes encoding these signaling molecules could affect the risk of breast cancer. We have investigated selected genetic polymorphisms in TNF-α promoter (rs1800629, -308 G>A and rs361525, -238 G>A) and TNF-β intron 1 (rs909253, +252 A>G) in ethnically two different case-control groups from India. The study included 200 cases and 200 controls from an Indo-European (North Indian) group, and 265 cases and 237 controls from a Dravidian (South Indian) group. Genotyping of a total of 902 individuals was done by direct DNA sequencing. None of the polymorphisms showed significant association with breast cancer in the Indo-European group; however, all the three polymorphisms showed strong association with breast cancer in the Dravidian group. Further, sub-group analysis in the Indo-European group showed no significant difference between pre-menopausal cases and controls or between post-menopausal cases and controls at any of the loci analyzed. However, all the polymorphisms in the Dravidian group were significantly associated with pre-menopausal but not with post-menopausal breast cancer. In conclusion, TNF-α and -β polymorphisms are strongly associated with breast cancer in the Dravidian but not in the Indo-European group.