Inherited mutations in BRCA1 and BRCA2 predispose to high risks of breast and ovarian cancer.^1,2 Lifetime risks of breast cancer are as high as 80% among US women with mutations in these genes, and lifetime risks of ovarian cancer are greater than 40% for carriers of the BRCA1 mutation and greater than 20% for carriers of the BRCA2 mutation. Risks for young women with inherited BRCA1 or BRCA2 mutations are particularly increased.¹ Among white women in the United States, 5% to 10% of breast cancer cases and 10% to 15% of ovarian cancer cases are due to inherited mutations in BRCA1 and BRCA2.^3-10

Rachael Stolzenberg-Solomon, Laufey Amundadottir and colleagues report a genome-wide association study of pancreatic cancer. They identify four new susceptibility loci. We performed a multistage genome-wide association study including 7,683 individuals with pancreatic cancer and 14,397 controls of European descent. Four new loci reached genome-wide significance: rs6971499 at 7q32.3 (LINC-PINT, per-allele odds ratio (OR) = 0.79, 95% confidence interval (CI) 0.74–0.84, P = 3.0 × 10−12), rs7190458 at 16q23.1 (BCAR1/CTRB1/CTRB2, OR = 1.46, 95% CI 1.30–1.65, P = 1.1 × 10−10), rs9581943 at 13q12.2 (PDX1, OR = 1.15, 95% CI 1.10–1.20, P = 2.4 × 10−9) and rs16986825 at 22q12.1 (ZNRF3, OR = 1.18, 95% CI 1.12–1.25, P = 1.2 × 10−8). We identified an independent signal in exon 2 of TERT at the established region 5p15.33 (rs2736098, OR = 0.80, 95% CI 0.76–0.85, P = 9.8 × 10−14). We also identified a locus at 8q24.21 (rs1561927, P = 1.3 × 10−7) that approached genome-wide significance located 455 kb telomeric of PVT1. Our study identified multiple new susceptibility alleles for pancreatic cancer that are worthy of follow-up studies.

In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10⁻⁸). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10⁻¹⁴), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10⁻¹⁰), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10⁻⁸), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10⁻⁸). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene.

Worldwide, colorectal cancer (CRC) is the third most common cancer, with the highest mortality rates occurring in Central Europe. The use of chemotherapy to treat CRC is limited by the inter-individual variability in drug response and the development of cancer cell resistance. ATP-binding cassette (ABC) transporters play a crucial role in the development of resistance by the efflux of anticancer agents outside of cancer cells. The aim of this study was to explore transcript levels of all human ABCs in tumours and non-neoplastic control tissues from CRC patients collected before the first line of treatment by 5-fluorouracil (5-FU)-containing regimen. The prognostic potential of ABCs was evaluated by the correlation of transcript levels with clinical factors. Relations between transcript levels of ABCs in tumours and chemotherapy efficacy were also addressed. The transcript profile of all known human ABCs was assessed using real-time polymerase chain reaction with a relative standard curve. The majority of the studied ABCs were down-regulated or unchanged between tumours and control tissues. ABCA12, ABCA13, ABCB6, ABCC1, ABCC2 and ABCE1 were up-regulated in tumours versus control tissues. Transcript levels of ABCA12, ABCC7 and ABCC8 increased in direction from colon to rectum. Additionally, transcript levels of ABCB9, ABCB11, ABCG5 and ABCG8 followed the reverse significant trend, i.e. a decrease in direction from colon to rectum. The transcript level of ABCC10 in tumours correlated with the grade (P = 0.01). Transcript levels of ABCC6, ABCC11, ABCF1 and ABCF2 were significantly lower in non-responders to palliative chemotherapy in comparison with responders. The disease-free interval of patients treated by adjuvant chemotherapy was significantly shorter in patients with low transcript levels of ABCA7, ABCA13, ABCB4, ABCC11 and ABCD4. In conclusion, ABCC11 may be a promising candidate marker for a validation study on 5-FU therapy outcome.

We analysed the associations between genetic polymorphisms in genes coding for DNA repair enzymes XPD (exon 23 A → C, K751Q), XPG (exon 15 G → C, D1104H), XPC (exon 15 A → C, K939Q), XRCC1 (exon 10 G → A, R399Q) and XRCC3 (exon 7 C → T, T241 M) and the levels of chromosomal aberrations (CAs) and single-strand breaks (SSBs) in peripheral lymphocytes in a central European population. We also measured the irradiation-specific DNA repair rates and the repair rates of 8-oxoguanines in these individuals. An elevated frequency of CAs was observed in individuals with the XPD exon 23 A allele (AA and AC) genotypes (F = 3.6, P = 0.028, ANOVA). In multifactorial analysis of variance, the XPD exon 23 polymorphism appeared as a major factor influencing CAs (F = 4.2, P = 0.017). SSBs in DNA, on the other hand, were modulated by XPD (F = 4.3, P = 0.023), XPG (F = 4.3, P = 0.024) and XRCC1 genotypes (F = 3.0, P = 0.064). Irradiation-specific DNA repair rates (reflecting mainly base excision repair activity) were affected by XRCC1 (F = 5.9, P = 0.010) and XPC polymorphisms (F = 4.2, P = 0.046, MANOVA). Our results from this study suggest that markers of genotoxicity are associated with polymorphisms in genes encoding DNA repair enzymes.