Lack of association between ACE insertion/deletion polymorphism and lung cancer: A meta-analysis

Association of a common genetic variant (insertion/deletion) in ACE gene with prostate cancer susceptibility in a Tunisian population

Background

Angiotensin‐converting enzyme (ACE) plays a pivotal role in several pathologies including cancers. The association of insertion/deletion (I/D) polymorphism of the ACE gene with prostate cancer (PC) risk remains controversial. We aimed to investigate for the first time, to our Knowledge, in North Africa the potential relationship between ACE I/D polymorphism with PC susceptibility and clinical outcomes of PC patients.

Methods

This case‐control study included 143 healthy individuals and 124 patients diagnosed with PC. Using genomic DNA, the samples were genotyped for ACE I/D polymorphism by polymerase chain reaction (PCR).

Results

We found that The D allele is significantly associated with an increased risk of PC and D/D + D/I genotypes were at 3 times increased risk of PC ([p = 0.005], OR = 2.95, IC 95% = 1.26–7.09) compared with I/I genotype (p = 0.003, OR = 0.3, IC 95% = 0.12–0.74). We observed an association between D/D and D/I genotypes with advanced age (≥70 years) (p = 0.014; r² = 0.22). Furthermore, there is a significant prediction of advanced Gleason score ≥8 based on epidemiological parameters and ACE genotype (p = 0.000; R² = 0.349), although no significant association was observed with stage and metastasis.

Conclusion

The ACE I/D polymorphism is likely to predispose to PC and could play a role in PC progression and aggressiveness.

Associations between I/D polymorphism in the ACE gene and lung cancer: an updated systematic review and a meta-analysis

Background

We evaluated the association between the I/D polymorphism in the ACE gene and lung cancer risk by performing a meta-analysis.

Methods

The heterogeneity in the study was tested using the Cochran χ²-based Q statistic test and I² test, and then the random ratio or fixed effect was utilized to merge the odds ratios (ORs) and 95% confidence intervals (CIs) to estimate the strength of the association between ACE polymorphisms and susceptibility to lung cancer. Sensitivity analysis was also performed. Using funnel plot and Begg’s rank test, we investigated the publication bias. All statistical analyses were performed using Stata 12.0 and RevMan 5.3.

Results

A total of 4307 participants (2181 patients; 2126 controls) were included in the 12 case–control studies. No significant association was found between the ACE I/D polymorphism and lung cancer risk (II vs. ID + DD: OR = 1.22, 95% CI = 0.89–1.68; II + ID vs. DD: OR = 1.21, 95% CI = 0.90–1.63; I vs. D: OR = 1.15, 95% CI = 0.95–1.39). In the subgroup analysis by ethnicity, no significant association between the ACE I/D polymorphism and lung cancer risk was found among Asian and Caucasian populations for the comparisons of II vs. ID + DD, II + ID vs. DD, and I vs. D genetic models.

Conclusion

The ACE I/D polymorphism is not associated with the risk of lung cancer.

Association between the ACE-I/D polymorphism and nicotine dependence amongst patients with lung cancer

The biologically active peptide angiotensin II is cleaved from angiotensinogen by the renin and the angiotensin-converting enzyme (ACE), an enzymatic cascade known as the renin-angiotensin system (RAS). RAS may be important in the etiology of nicotine dependence by influencing dopaminergic signaling. In the present study, the association between an insertion/deletion (I/D) polymorphism of ACE and nicotine dependence amongst patients with lung cancer was assessed. To date, several studies have shown the relevance of this polymorphic variant in both nicotine dependence and lung cancer. However, the present study is the first to address the potential role of the ACE-I/D polymorphism in nicotine dependence among patients with lung cancer. Genotyping was performed in 305 patients with lung cancer (males/females, 214/91). Significantly more male smokers had the ACE-I allele compared with male non-smokers (44.9 vs. 20.0%; P<0.05). The risk of smoking was ~5-fold higher for males with the ACE-I allele (ACE-II homozygous and ACE-ID heterozygous) vs. ACE-DD homozygous (odds ratio, 5.47; 95% confidence interval, 1.4-21.9; P=0.016). The pack-year smoking history in a subgroup of females with squamous cell carcinoma carrying the ACE-I allele was significantly lower compared with ACE-DD (37.1±14.1 vs. 57.0±29.1; F=4.5; P=0.046). The ACE-I/D polymorphism accounted for 17.6% of the smoking severity in this patient group (β, -0.42; multiple R² change, 0.176; P=0.046). These results suggest that the ACE-I/D polymorphism contributes to the risk of nicotine dependence and smoking severity in lung cancer patients in a sex-specific manner.

Association of ACE I/D, -240A > T and AT1R A1166C polymorphisms with susceptibility to breast cancer: a systematic review and meta-analysis based on 35 case-control studies

The objective of this meta-analysis was to estimate the association of ACE I/D, -240 A > T and AT1R 1166 A > C polymorphisms with breast cancer (BC) risk. A comprehensive search on databases was conducted to identify all eligible case-control studies. Finally, 35 case-control studies, including 20 studies for ACE I/D, seven studies for ACE 240 A > T, and eight studies for AT1R 1166 A > C were included. The pooled analysis showed a significant association between ACE I/D polymorphism and BC risk under three genetic models, i.e., heterozygote (ID vs. DD: OR = 0.707, 95% CI 0.528-0.946, p = 0.020), homozygote (II vs. DD: OR = 0.662, 95% CI 0.462-0.947, p = 0.024), and dominant (II + ID vs. DD: OR = 0.691, 95% CI 0.507-0.941, p = 0.019). A significant association was also observed in ACE I/D polymorphism with BC risk among Asians and Caucasians. However, ACE -240 A > T and AT1R 1166 A > C polymorphisms were not associated with BC. Stratified analyses by ethnicity showed a significant association of ACE -240 A > T and AT1R 1166 A > C polymorphisms with BC risk in Latinos populations, but not in Asians. This meta-analysis inconsistence with all previous meta-analyses suggests that the ACE I/D might be associated with BC in overall and by ethnicity. However, the ACE -240 A > T and AT1R 1166 A > C were associated with BC risk only among Latinos populations.

[Advance in Research of Angiotensin II and Its Receptor and Malignant Tumor]

Angiotensin AngII, a linear small peptide,which is composed of eight amino acids, is the main effectors of renin-angiotensin systen (Renin-angiotensin system, RAS). AngII, a main biopolypeptide of the RAS, has important pathophysiologic in effects participating in cardiac hypertrophy, vascular cell proproliferation, inflammation and tissue remodeling through G-protein-coupled receptors. In recent years, Ang II can promote tumor cell proliferation, tumor vessel formation and inhibit the differentiation of the tumor cells. This suggests that inhibit the production of AngII or block its effect is expected to become a new measure for the treatment of malignant tumors. This article reviews the advances in research on the relationship between AngII and its receptor and malignant tumor in recent years.