A systematic review and network meta-analysis of single nucleotide polymorphisms associated with pancreatic cancer risk

Analysis of Pancreatic Cancer Genetic Risk Factors in a Multi-Ethnic Population Sample

Background

Pancreatic cancer (PC) has one of the highest mortality to incidence ratio of all cancers. Early identification of at-risk individuals should permit early diagnosis. Genome-wide association studies showed the association of several genetic variants with PC risk in multi-ethnic populations. Our objective was to examine the association of these genetic variants with PC in a population sample from Kuwait.

Methods

DNA samples from 103 pancreatic ductal adenocarcinoma (PDAC) specimens and 132 healthy controls were used for genotyping ABO rs505922, BCAR1 rs7190458, LINC-PINT rs6971499, HNF1B rs4795218, VDR rs2228570 rs731236, and PRSS1 rs111033565 rs111033568 rs387906698 and rs267606982 using TaqMan genotyping assays, and VDR expression was performed by immunocytochemistry.

Results

ABO rs505922C and VDR rs2228570A were associated with PDAC risk (odds ratio (OR): 1.55, 95% confidence interval (CI): 1.07 - 2.24, P = 0.027; OR: 1.64, 95% CI: 1.09 - 2.48, P = 0.024; respectively). An unweighted polygenic risk score (ABO rs505922, BCAR1 rs7190458, LINC-PINT rs6971499, and HNF1B rs4795218) was significantly associated with PDAC risk (β: -0.11, 95% CI: -0.15 to -0.05, P < 0.001). VDR expression was downregulated or absent in most PDAC specimens regardless of VDR haplotype.

Conclusion

ABO rs505922C and VDR rs2228570A are PDAC genetic risk factors in our population. Ethnicity influences the association of reported genetic PDAC risk factors and should be adjusted for when performing PDAC genetic risk estimations. Investigation of these genetic risk factors in other ethnic populations is a necessity to evaluate their PDAC risk prediction potential.

Identification of gemcitabine resistance-related AHNAK2 gene associated with prognosis and immune infiltration in pancreatic cancer

Purpose

Gemcitabine is a basic chemotherapy drug for pancreatic cancer (PC), but resistance is common and causes tumor recurrence and metastasis. Therefore, it is significant to explore gemcitabine resistance-related molecules for individualized treatment and prognosis assessment of PC.

Methods

In this study, transcriptome sequencing and TCGA database analysis were performed, and a differentiated gene AHNAK2 was screened. MEXPRESS database, tissue microarray analysis, and CIBERSORT and TIMER databases were used to correlate AHNAK2 expression with clinicopathological features and prognosis and immune infiltration of PC. Enrichment analysis was used to investigate the significant biological processes associated with AHNAK2.

Results

AHNAK2 was highly expressed in gemcitabine-resistant cells. High expression of AHNAK2 increased the risk of poor overall survival (OS) and progression-free survival (PFS) in PC. Clinicopathologic analysis revealed that AHNAK2 correlated with KRAS, TP53 mutations, histologic type, short OS, N stage, and elevated CA199 levels in PC. Knockdown of AHNAK2 inhibited the ability of cell proliferation and colony formation and enhanced the toxic effect of gemcitabine in PC. Meanwhile, the knockdown of AHNAK2 expression enhanced cell-ECM adhesion, inhibited cell-cell adhesion, and downregulated the KRAS/p53 signaling pathway in PC. Furthermore, AHNAK2 was correlated with immune infiltration, especially B cells and macrophages.

Conclusions

Our study unveils for the first time the pivotal role of AHNAK2 in PC, particularly its association with gemcitabine resistance, clinical prognosis, and immune infiltration. AHNAK2 not only drives the proliferation and drug resistance of PC cells by potentially activating the KRAS/p53 pathway but also significantly impacts cell-cell and cell- ECM adhesion. Additionally, AHNAK2 plays a crucial role in modulating the tumor immune microenvironment. These insights underscore AHNAK2's unique potential as a novel therapeutic target for overcoming gemcitabine resistance, offering new perspectives for PC treatment strategies.

Superoxide Dismutase (rs2070424, rs4880, rs2536512) and Catalase (rs794316, rs1001179) SNPs and their Association with Breast Cancer Risk: Findings from a Hospital Based Case-Control Study

BACKGROUND

The antioxidant enzymes are important cellular components involved in detoxification of reactive oxygen species (ROS) and protect cells from ROS induced oxidative damage. Single nucleotide polymorphisms (SNPs) of antioxidant enzyme coding genes such as superoxide dismutase (SOD) and catalase (CAT) may alter the enzyme activity which can influence susceptibility towards carcinogenesis.  Therefore, the present study was planned to investigate possible SNPs of SOD (SOD1 (Cu,Zn-SOD), SOD2(Mn-SOD), SOD3(EC-SOD) and CAT genes and their possible association with breast cancer risk in rural Indian women.

METHODS

In this case-control study, the association of SOD and CAT gene polymorphism was studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The study was conducted among 400 clinically breast cancer patients and 400 healthy women in a population of South-Western Maharashtra. The logistic regression analysis was carried out to calculate Odds ratio (OR) with 95% confidence interval and p-value, where p ≤0.05 was considered as statistically significant.

RESULTS

The results of analysis of genotype frequency distribution showed significant association of rs4880 SNP of Mn-SOD with BC risk at homozygous variant (CC/CC) genotype (OR 2.46; 95%CI, 1.61-3.75; p<0.0001) and corresponding frequency of variant (C) allele (OR 1.53; 95%CI, 1.25-1.86; p<0.0001). In CAT gene polymorphisms the variant (T/T) was increased significantly in BC cases as compared to controls (OR 3.45; 95%CI, 2.17-5.50; p<0.0001) along with its variant (T) allele (OR 2.01; 95%CI, 1.63-2.48; p<0.0001).

CONCLUSIONS

The results implied that, C/C genotype of SOD2-1183T/C polymorphism and T/T genotype of CAT-262 C/T polymorphism may be associated with an increased breast cancer risk. However, SOD1-251 A/G and SOD3-172 G/A polymorphisms did not show any significant difference in variant homozygous genotypes of patients compared to controls.

Association of a Genetic Variant in the Cyclin-Dependent Kinase Inhibitor 2B with Risk of Pancreatic Cancer

BACKGROUND

Pancreatic cancer (PC) is among the most aggressive tumors with a poor prognosis, indicating the need for the identification of a novel prognostic biomarker for risk stratifications. Recent genome-wide association studies have demonstrated common genetic variants in a region on chromosome 9p21 associated with an increased risk of different malignancies.

METHODS

In the present study, we explore the possible relationship between genetic variant, rs10811661, and gene expression of CDKN2B in 75 pancreatic cancer patients, and 188 healthy individuals. DNAs were extracted and genotyping and gene expression were performed by TaqMan real-time PCR and RT-PCR, respectively. Logistic regression was used to assess the association between risk and genotypes, while the significant prognostic variables in the univariate analysis were included in multivariate analyses.

RESULTS

The patients with PDAC had a higher frequency of a TT genotype for rs10811661 than the control group. Also, PDAC patients with dominant genetic model, (TT + TC), was associated with increased risk of developing PDAC (OR= 14.71, 95% CI [1.96-110.35], p= 0.009). Moreover, patients with CC genotype had a higher expression of CDKN2B, in comparison with TT genotype.

CONCLUSION

Our findings demonstrated that CDKN2A/B was associated with the risk of developing PDAC, supporting further investigations in the larger and multicenter setting to validate the potential value of this gene as an emerging marker for PDAC.

FTO Gene Polymorphisms Contribute to the Predisposition and Radiotherapy Efficiency of Nasopharyngeal Carcinoma

Background

Nasopharyngeal carcinoma (NPC) is mainly concentrated in East and Southeast Asia. This study aims to elucidate the potential associations of functional SNPs in the fat mass and obesity associated gene (FTO) with NPC risk and radiotherapy outcomes in a Chinese population.

Methods

Functional SNP rs1477196 G>A, rs9939609 T>A, rs7206790 C>G, and rs8047395 A>G were genotyped and evaluated for their associations with NPC risk and radiotherapy outcomes.

Results

Both rs9939609 (allele A versus allele T: OR=1.59; 95% CI=1.17–2.17; P-value=0.003) and rs8047395 (allele G versus allele A: OR=0.76; 95% CI=0.64–0.9; P-value=0.002) were significantly associated with risk of NPC. GTEx showed risk allele A of rs9939609 and rs8047395 were significantly associated with higher FTO mRNA levels in skeletal muscle tissue, which also corroborated our findings. Meanwhile, both rs1477196 (allele A versus allele G: OR=1.64; 95% CI=1.09–2.49; P-value=0.019) and rs9939609 (allele A versus allele T: OR=0.61; 95% CI=0.43–0.87; P-value=0.006) were significantly associated with complete remission (CR) of NPC.

Conclusion

Our study identified that FTO polymorphisms contributed to the susceptibility and radiotherapy efficacy of NPC. These results shed light on the potential of establishing markers for predicting risk and personalized treatment of NPC.