Interaction among susceptibility genotypes of PARP1 SNPs in thyroid carcinoma

Polymorphisms of DNA Repair Genes in Thyroid Cancer

The incidence of thyroid cancer, one of the most common forms of endocrine cancer, is increasing rapidly worldwide in developed and developing countries. Various risk factors can increase susceptibility to thyroid cancer, but particular emphasis is put on the role of DNA repair genes, which have a significant impact on genome stability. Polymorphisms of these genes can increase the risk of developing thyroid cancer by affecting their function. In this article, we present a concise review on the most common polymorphisms of selected DNA repair genes that may influence the risk of thyroid cancer. We point out significant differences in the frequency of these polymorphisms between various populations and their potential relationship with susceptibility to the disease. A more complete understanding of these differences may lead to the development of effective prevention strategies and targeted therapies for thyroid cancer. Simultaneously, there is a need for further research on the role of polymorphisms of previously uninvestigated DNA repair genes in the context of thyroid cancer, which may contribute to filling the knowledge gaps on this subject.

A functional polymorphism in the poly(ADP-ribose) polymerase-1 gene increases the risk of endometrial carcinoma

The aim of this study was to investigate the effects of two functional genetic polymorphisms in the poly(ADP-ribose) polymerase-1 (PARP-1) gene on the risk of endometrial carcinoma (EC). Genotypes of the rs1136410 and rs8679 polymorphisms were determined by polymerase chain reaction and ligase detection reaction in 327 EC patients and 329 controls. The results showed that there were significant differences in the genotype distributions of rs1136410 between cases and controls. Women carrying the rs1136410 CC genotype had a significantly increased risk of EC compared to those with the rs1136410 TT genotype (OR = 1.73, 95% CI = 1.10-2.72, p = .018). After adjustment for clinical characteristics, the rs1136410 CC genotype still significantly increased the risk of EC (adjusted OR = 1.83, 95% CI = 1.09-3.07, p = .021). However, no significant difference was observed in the genotype frequencies of rs8679 between cases and controls. This study indicated that rs1136410 was related to the risk of developing EC, and the CC genotype of rs1136410 may be a risk factor for EC in the northern Chinese population.IMPACT STATEMENTWhat is already known on this subject? Genetic variations in the PARP-1 gene may affect protein function and hence reduce DNA repair capacity, leading to the accumulation of DNA damage and a subsequent increased probability of tumorigenesis. Previous studies have shown that polymorphisms of the PARP-1 gene are associated with the risk of various carcinomas, including breast cancer, lung cancer, thyroid cancer, colorectal cancer, and oral squamous cell carcinoma.What do the results of this study add? Our results suggest that the rs1136410 polymorphism of PARP-1 was related to the risk of developing endometrial carcinoma, and the CC genotype of rs1136410 may be a risk factor for endometrial carcinoma in the northern Chinese population.What are the implications of these findings for clinical practice and/or further research? The new genetic marker may help to identify genetic basis of endometrial carcinoma, and develop gene-targeted therapies for endometrial carcinoma.

A Genome Wide Association Study Revealed Key Single Nucleotide Polymorphisms/Genes Associated With Seed Germination in Gossypium hirsutum L

Fast and uniform seed germination is essential to stabilize crop yields in agricultural production. It is important to understand the genetic basis of seed germination for improving the vigor of crop seeds. However, little is known about the genetic basis of seed vigor in cotton. In this study, we evaluated four seed germination-related traits of a core collection consisting of 419 cotton accessions, and performed a genome-wide association study (GWAS) to explore important loci associated with seed vigor using 3.66 million high-quality single nucleotide polymorphisms (SNPs). The results showed that four traits, including germination potential, germination rate, germination index, and vigor index, exhibited broad variations and high correlations. A total of 92 significantly associated SNPs located within or near 723 genes were identified for these traits, of which 13 SNPs could be detected in multiple traits. Among these candidate genes, 294 genes were expressed at seed germination stage. Further function validation of the two genes of higher expression showed that Gh_A11G0176 encoding Hsp70-Hsp90 organizing protein negatively regulated Arabidopsis seed germination, while Gh_A09G1509 encoding glutathione transferase played a positive role in regulating tobacco seed germination and seedling growth. Furthermore, Gh_A09G1509 might promote seed germination and seedling establishment through regulating glutathione metabolism in the imbibitional seeds. Our findings provide unprecedented information for deciphering the genetic basis of seed germination and performing molecular breeding to improve field emergence through genomic selection in cotton.

PARP1 rs1136410 (A/G) polymorphism is associated with early age of onset of gallbladder cancer

OBJECTIVES

Evaluation of the association of PARP1 rs1136410 (A/G) polymorphism with gallbladder cancer susceptibility and its prognosis in the Indian population of eastern Uttar Pradesh and western Bihar.

METHODS

PARP1 rs1136410 was genotyped by PCR-RFLP and its association with the prognosis of gallbladder cancer patients were analyzed using Kaplan-Meier plot and log-rank tests.

RESULTS

Our results demonstrate that minor allele G is more frequent in gallbladder cancer patients than controls. The frequencies of minor allele G and GG genotype are significantly associated with increased risk of gallbladder cancer. Our data suggest that the minor allele G and homozygous genotype GG are significant predisposing factors for the early age of onset of gallbladder cancer. Similarly, women patients having AG and GG genotypes demonstrate an increased risk of gallbladder cancer. The risk group genotypes (AG + GG) are significantly more frequent in patients with thick gallbladder wall, with jaundice and with the presence of lymph node than in patients with normal gallbladder wall thickness, without jaundice and absence of lymph node involvement. Survival analysis data suggest that patients with risk group genotype (AG + GG) presenting jaundice have shorter overall survival.

CONCLUSION

Our study suggests that the minor allele G of PARP1 rs1136410 (A/G) is a predisposing factor for gallbladder carcinogenesis and is significantly associated with early onset of the disease. Interestingly, the minor allele G is significantly more frequent in the patients with jaundice, lymph node metastasis and gallbladder wall thickness.

Genetic and expression deregulation of immunoregulatory genes in rheumatoid arthritis

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases globally, and is an important public health concern, associating with early death and systemic complications. Although key development in RA treatment has already been made still RA affected individuals face comorbidity and disability. Therefore, there is a need to discover new risk factors in helping early diagnosis and treatment of RA. The present study is designed to assess the variations of Vitamin D receptor (VDR) and interleukin -6 (IL-6) in RA patients. Polymorphisms of said genes were calculated in 300 RA patients and 300 controls, using Tetra-ARMS polymerase chain reaction. Secondly, expression levels of selected genes were checked using the quantitative PCR (qPCR) and obtained results were evaluated using a different statistical test. Logistic regression analysis showed that frequency of mutant allele of VDR gene polymorphisms (rs11168268, OR = 4.84; 95% CI = 2.94-7.97; p = 0.0001; rs2248098, OR = 1.65; 95% CI = 1.07-2.54; p = 0.02) and IL-6 gene polymorphisms (rs184229712, OR = 2.47; 95% CI = 1.56-3.92, p = 0.0001; rs36215814, OR = 2.14; 95% CI = 1.30-3.53; p = 0.002) was observed significantly higher in RA patients vs controls. Expression analysis showed the significant upregulation of IL-6 (p < 0.0001) and downregulation of VDR gene (p < 0.0001) in RA cases vs controls. ROC curve analysis showed that downregulation of IL-6 (AUC = 0.86, p < 0.001) and upregulation of VDR (AUC = 0.77, p < 0.001) was act as the good diagnostic marker for detection/diagnosis of arthritis. In conclusions, data from the present study showed the significant involvement of VDR and IL-6 gene variations in RA pathogenesis.

Association of T2285C polymorphism in PARP1 gene coding region with its expression, activity and NSCLC risk along with prognosis

Poly (ADP-ribose) polymerase-1(PARP1), a DNA repair gene, is the crucial player in the maintenance of genome integrity. T2285C polymorphism in coding region of PARP1 has been reported to be associated with susceptibility to tumors. We explored the relation and mechanism of T2285C polymorphism of PARP1 to its expression and activity along with risk and prognosis in NSCLC. mRNA expression was measured using qRT-PCR assay or collected from TCGA dataset. Protein expression was examined with immunoblotting assay. Genotypes were determined by PCR-RFLP and sequencing approaches. PARP1 activity was determined with enzyme activity assay. Regulation of SIRT7 to PARP1 were determined by over-expression and small interference experiment. Association of PARP1 T2285C polymorphism with NSCLC risk was evaluated via multiple logistic regression analysis. Comparison of treatment response and PFS of NSCLC patients among different genotypes or regimens was made by Chi-square test. Results indicated that mRNA and protein expression of PARP1 dramatically increased in NSCLC tissues in comparison to paired para-carcinoma tissues (P<0.05). TC/CC mutant genotypes were associated with markedly enhanced PARP1 mRNA level compared with TT genotype (P=0.011). No significant difference was discovered in PARP1 protein expression among TT, TC or CC genotypes (P>0.05). Subjects with variant allele C had higher risk of NSCLC in comparison to allele T carriers [odds ratio (OR) =1.560; P=0.000]. NSCLC patients carrying mutational TC or CC genotypes were correlated with unfavorable response to platinum-based chemotherapy (TT vs.TC vs.CC, P=0.010), and shorter PFS compared to TT genotype (TT vs.TC vs.CC, P=0.009). T2285C mutation of PARP1 resulted in the enhancement of its mRNA, but the decrease of enzyme activity in tumor cell. Overexpression of SIRT7 attenuated PARP1 expression and activity. These findings suggest the variant allele C of T2285C polymorphism of PARP1 linked to an increase of NSCLC risk, and unfavorable efficacy and prognosis of NSCLC patients with platinum-based chemotherapy, which might be associated with enhancement of its mRNA expression and the diminishment of activity. Identification of PARP1 T2285C polymorphism and mRNA expression may be the promising way for the individualized treatment of NSCLC.

Association between single nucleotide polymorphisms of DNA damage response pathway genes and increased risk in breast cancer

Aim: We aimed to evaluate the role of selected single nucleotide polymorphisms of DNA damage response pathway genes in breast cancer (BC). Materials & methods: In present study, 500 BC patients and 500 controls was used to estimate the frequency of single nucleotide polymorphisms of DNA damage response pathway genes. Tetra-amplification refractory mutation system-PCR technique was used for screening of the six selected polymorphisms. Results: Logistic regression analysis showed that heterozygous mutant genotype of rs1800057 (p < 0.0001) and homozygous mutant genotype of rs1801516 (p < 0.0001) was associated with significant increased risk of BC. In the ATR gene, heterozygous mutant genotype of rs2227931 (p < 0.0001) was associated with significant increased risk of BC. However, significant decreased risk of BC was found associated with heterozygous mutant genotype of rs2227928 (p < 0.0002) and homozygous mutant genotype of rs2229032 (p < 0.0001) in patients compared with controls. Conclusion: The present results showed that alteration in DNA damage response pathway gene (ATM & ATR) results in increased BC risk.

Association of PARP1 polymorphisms with response to chemotherapy in patients with high-risk neuroblastoma

The genetic aetiology and the molecular mechanisms that characterize high‐risk neuroblastoma are still little understood. The majority of high‐risk neuroblastoma patients do not take advantage of current induction therapy. So far, one of the main reasons liable for cancer therapeutic failure is the acquisition of resistance to cytotoxic anticancer drugs, because of the DNA repair system of tumour cells. PARP1 is one of the main DNA damage sensors involved in the DNA repair system and genomic stability. We observed that high PARP1 mRNA level is associated with unfavourable prognosis in 3 public gene expression NB patients’ datasets and in 20 neuroblastomas analysed by qRT‐PCR. Among 4983 SNPs in PARP1, we selected two potential functional SNPs. We investigated the association of rs907187, in PARP1 promoter, and rs2048426 in non‐coding region with response chemotherapy in 121 Italian patients with high‐risk NB. Results showed that minor G allele of rs907187 associated with induction response of patients (P = .02) and with decrease PARP1 mRNA levels in NB cell line (P = .003). Furthermore, rs907187 was predicted to alter the binding site of E2F1 transcription factor. Specifically, allele G had low binding affinity with E2F1 whose expression positively correlates with PARP1 expression and associated with poor prognosis of patients with NB. By contrast, we did not find genetic association for the SNP rs2048426. These data reveal rs907187 as a novel potential risk variant associated with the failure of induction therapy for high‐risk NB.

Thyroid Cancer: The Quest for Genetic Susceptibility Involving DNA Repair Genes

The incidence of thyroid cancer (TC), particularly well-differentiated forms (DTC), has been rising and remains the highest among endocrine malignancies. Although ionizing radiation (IR) is well established on DTC aetiology, other environmental and genetic factors may also be involved. DNA repair single nucleotide polymorphisms (SNPs) could be among the former, helping in explaining the high incidence. To further clarify the role of DNA repair SNPs in DTC susceptibility, we analyzed 36 SNPs in 27 DNA repair genes in a population of 106 DTCs and corresponding controls with the aim of interpreting joint data from previously studied isolated SNPs in DNA repair genes. Significant associations with DTC susceptibility were observed for XRCC3 rs861539, XPC rs2228001, CCNH rs2230641, MSH6 rs1042821 and ERCC5 rs2227869 and for a haplotype block on chromosome 5q. From 595 SNP-SNP combinations tested and 114 showing relevance, 15 significant SNP combinations (p < 0.01) were detected on paired SNP analysis, most of which involving CCNH rs2230641 and mismatch repair variants. Overall, a gene-dosage effect between the number of risk genotypes and DTC predisposition was observed. In spite of the volume of data presented, new studies are sought to provide an interpretability of the role of SNPs in DNA repair genes and their combinations in DTC susceptibility.