Alison Klein and colleagues report a genome-wide meta-analysis to identify loci associated with pancreatic cancer risk. They identify associated variants at 17q25.1, 3q29, 7p13 and 2p13.3. Pancreatic cancer is the fourth leading cause of cancer death in the developed world1. Both inherited high-penetrance mutations in BRCA2 (ref. 2), ATM3, PALB2 (ref. 4), BRCA1 (ref. 5), STK11 (ref. 6), CDKN2A7 and mismatch-repair genes8 and low-penetrance loci are associated with increased risk9,10,11,12. To identify new risk loci, we performed a genome-wide association study on 9,925 pancreatic cancer cases and 11,569 controls, including 4,164 newly genotyped cases and 3,792 controls in 9 studies from North America, Central Europe and Australia. We identified three newly associated regions: 17q25.1 (LINC00673, rs11655237, odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.19–1.34, P = 1.42 × 10−14), 7p13 (SUGCT, rs17688601, OR = 0.88, 95% CI = 0.84–0.92, P = 1.41 × 10−8) and 3q29 (TP63, rs9854771, OR = 0.89, 95% CI = 0.85–0.93, P = 2.35 × 10−8). We detected significant association at 2p13.3 (ETAA1, rs1486134, OR = 1.14, 95% CI = 1.09–1.19, P = 3.36 × 10−9), a region with previous suggestive evidence in Han Chinese12. We replicated previously reported associations at 9q34.2 (ABO)9, 13q22.1 (KLF5)10, 5p15.33 (TERT and CLPTM1)10,11, 13q12.2 (PDX1)11, 1q32.1 (NR5A2)10, 7q32.3 (LINC-PINT)11, 16q23.1 (BCAR1)11 and 22q12.1 (ZNRF3)11. Our study identifies new loci associated with pancreatic cancer risk.

Altered expression of microRNAs (miRNAs) hallmarks many cancer types. The study of the associations of miRNA expression profile and cancer phenotype could help identify the links between deregulation of miRNA expression and oncogenic pathways. Expression profiling of 866 human miRNAs in 19 colorectal and 17 pancreatic cancers and in matched adjacent normal tissues was investigated. Classical paired t-test and random forest analyses were applied to identify miRNAs associated with tissue-specific tumors. Network analysis based on a computational approach to mine associations between cancer types and miRNAs was performed. The merge between the two statistical methods used to intersect the miRNAs differentially expressed in colon and pancreatic cancers allowed the identification of cancer-specific miRNA alterations. By miRNA-network analysis, tissue-specific patterns of miRNA deregulation were traced: the driving miRNAs were miR-195, miR-1280, miR-140-3p and miR-1246 in colorectal tumors, and miR-103, miR-23a and miR-15b in pancreatic cancers. MiRNA expression profiles may identify cancer-specific signatures and potentially useful biomarkers for the diagnosis of tissue specific cancers. miRNA-network analysis help identify altered miRNA regulatory networks that could play a role in tumor pathogenesis.

The clock gene machinery controls cellular metabolism, proliferation, and key functions, such as DNA damage recognition and repair. Dysfunction of the circadian clock is involved in tumorigenesis, and altered expression of some clock genes has been found in cancer patients. The aim of this study was to evaluate the expression levels of core clock genes in colorectal cancer (CRC). Quantitative real-time polymerase chain reaction (qPCR) was used to examine ARNTL1, CLOCK, PER1, PER2, PER3, CRY1, CRY2, Timeless (TIM), TIPIN, and CSNK1Ε expression levels in the tumor tissue and matched apparently healthy mucosa of CRC patients. In the tumor tissue of CRC patients, compared to their matched healthy mucosa, expression levels of ARNTL1 (p = .002), PER1 (p = .002), PER2 (p = .011), PER3 (p = .003), and CRY2 (p = .012) were lower, whereas the expression level of TIM (p = .044) was higher. No significant difference was observed in the expression levels of CLOCK (p = .778), CRY1 (p = .600), CSNK1Ε (p = .903), and TIPIN (p = .136). As to the clinical and pathological features, a significant association was found between low CRY1 expression levels in tumor mucosa and age (p = .026), and female sex (p = .005), whereas high CRY1 expression levels in tumor mucosa were associated with cancer location in the distal colon (p = .015). Moreover, high TIM mRNA levels in the tumor mucosa were prevalent whenever proximal lymph nodes were involved (p = .013) and associated with TNM stages III–IV (p = .005) and microsatellite instability (p = .015). Significantly poorer survival rates were evidenced for CRC patients with lower expression in the tumor tissue of PER1 (p = .010), PER3 (p = .010), and CSNKIE (p = .024). In conclusion, abnormal expression levels of core clock genes in CRC tissue may be related to the process of tumorigenesis and exert an influence on host/tumor interactions. (Author correspondence: g. mazzoccoli@tin. it )

Alzheimer's Disease (AD) is the most common neurodegenerative disease and the leading cause of dementia among senile subjects. It has been proposed that AD can be caused by defects in mitochondrial oxidative phosphorylation. Given the fundamental contribution of the mitochondrial genome (mtDNA) for the respiratory chain, there have been a number of studies investigating the association between mtDNA inherited variants and multifactorial diseases, however no general consensus has been reached yet on the correlation between mtDNA haplogroups and AD. We applied for the first time a high resolution analysis (sequencing of displacement loop and restriction analysis of specific markers in the coding region of mtDNA) to investigate the possible association between mtDNA-inherited sequence variation and AD in 936 AD patients and 776 cognitively assessed normal controls from central and northern Italy. Among over 40 mtDNA sub-haplogroups analysed, we found that sub-haplogroup H5 is a risk factor for AD (OR = 1.85, 95% CI:1.04–3.23) in particular for females (OR = 2.19, 95% CI:1.06–4.51) and independently from the APOE genotype. Multivariate logistic regression revealed an interaction between H5 and age. When the whole sample is considered, the H5a subgroup of molecules, harboring the 4336 transition in the tRNA^Gln gene, already associated to AD in early studies, was about threefold more represented in AD patients than in controls (2.0% vs 0.8%; p = 0.031), and it might account for the increased frequency of H5 in AD patients (4.2% vs 2.3%). The complete re-sequencing of the 56 mtDNAs belonging to H5 revealed that AD patients showed a trend towards a higher number (p = 0.052) of sporadic mutations in tRNA and rRNA genes when compared with controls. Our results indicate that high resolution analysis of inherited mtDNA sequence variation can help in identifying both ancient polymorphisms defining sub-haplogroups and the accumulation of sporadic mutations associated with complex traits such as AD.

A small number of common susceptibility loci have been identified for pancreatic cancer, one of which is marked by rs401681 in the TERT–CLPTM1L gene region on chromosome 5p15.33. Because this region is characterized by low linkage disequilibrium, we sought to identify whether additional single nucleotide polymorphisms (SNPs) could be related to pancreatic cancer risk, independently of rs401681. We performed an in‐depth analysis of genetic variability of the telomerase reverse transcriptase (TERT) and the telomerase RNA component (TERC) genes, in 5,550 subjects with pancreatic cancer and 7,585 controls from the PANcreatic Disease ReseArch (PANDoRA) and the PanScan consortia. We identified a significant association between a variant in TERT and pancreatic cancer risk (rs2853677, odds ratio = 0.85; 95% confidence interval = 0.80–0.90, p = 8.3 × 10⁻⁸). Additional analysis adjusting rs2853677 for rs401681 indicated that the two SNPs are independently associated with pancreatic cancer risk, as suggested by the low linkage disequilibrium between them (r² = 0.07, D′ = 0.28). Three additional SNPs in TERT reached statistical significance after correction for multiple testing: rs2736100 (p = 3.0 × 10⁻⁵), rs4583925 (p = 4.0 × 10⁻⁵) and rs2735948 (p = 5.0 × 10⁻⁵). In conclusion, we confirmed that the TERT locus is associated with pancreatic cancer risk, possibly through several independent variants.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most deadly cancers, being the fourth leading cause of cancer-related deaths. Long-term survival reaching 15% is achieved in less than 5% of patients who undergo surgery, and median survival is only 6 months in those with inoperable lesions. A deeper understanding of PDAC biologic characteristics as well as novel prognostic markers are therefore required to improve outcomes. Herein we report that BAG3, a protein with recognized anti-apoptotic activity, was expressed in 346 PDACs analyzed, but was not expressed in the surrounding nonneoplastic tissue. In a cohort of 66 patients who underwent radical resection (R0), survival was significantly shorter in patients with high BAG3 expression (median, 12 months) than in those with low BAG3 expression (median, 23 months) (P = 0.001). Furthermore, we report that BAG3 expression in PDAC-derived cell lines protects from apoptosis and confers resistance to gemcitabine, offering a partial explanation for the survival data. Our results indicate that BAG3 has a relevant role in PDAC biology, and suggest that BAG3 expression level might be a potential marker for prediction of patient outcome.