Long noncoding RNAs (lncRNAs) are an important class of functional regulators involved in human cancers development, including gastric cancer (GC). Studying aberrantly expressed lncRNAs may provide us with new insights into the occurrence and development of gastric cancer by acting as oncogenes or tumor suppressors. In this study, we aim to examine the expression pattern of lncRNA HAGLROS in GC and its clinical significance as well as its biological role in tumor progression. Bioinformatics analysis and qRT-PCR were performed to detect the relative expression of HAGLROS in GC tissues and cell lines. Gain or loss of function approaches were used to investigate the biological functions of HAGLROS. The effect of HAGLROS on proliferation was evaluated by MTT, colony formation assay and nude mouse xenograft model. Wound healing and Transwell assays were used to study the invasion and migration of GC cells. FISH, RIP, RNA-seq, Luciferase report assays, RNA pulldown and Western blot were fulfilled to measure molecular mechanisms. Results are shown as means ± S.D. and differences were tested for significance using Student’s t-test (two-tailed). We screened out HAGLROS, whose expression was significantly increased and correlated with outcomes of GC patients by publicly available lncRNAs expression profiling and integrating analyses. Exogenous down-regulation of HAGLROS expression significantly suppressed the cell proliferation, invasion and migration. Mechanistic investigations showed that HAGLROS was a direct target of transcriptional factor STAT3. Moreover, HAGLROS knockdown decreased mTOR expression and increased autophagy-related genes ATG9A and ATG9B expression. Further investigation showed that HAGLROS regulated mTOR signals in two manners. In the one hand, HAGLROS competitively sponged miR-100-5p to increase mTOR expression by antagonizing miR-100-5p-mediated mTOR mRNA inhibition. On the other hand, HAGLROS interacted with mTORC1 components to activate mTORC1 signaling pathway which was known to be an important negative signal of autophagy. Here activation of mTORC1 signaling pathway by HAGLROS inhibited autophagy, thereby promoted excessive proliferation and maintained the malignant phenotype of GC cells. The present study demonstrates that HAGLROS overexpression contributes to GC development and poor prognosis and will be a target for GC therapy and further develop as a potential prognostic biomarker.

Obesity is correlated with increased colorectal cancer (CRC) risk, but few studies have investigated lifetime body mass index (BMI) metrics and CRC risk. In a cohort of 139 229 subjects in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, we analysed the effects of life-course BMI trajectories on CRC risk. At 13 years of follow-up, 2031 subjects developed CRC. Compared with subjects who were never overweight/obese, subjects who first exceeded the threshold of 25 kg m⁻² at age 20 had a higher CRC risk (HR = 1.28, 95% confidence interval (CI) = 1.11–1.48). A body weight gain of ≥15 kg between 20 and 50 years of age (HR = 1.34, 95% CI = 1.18–1.52) and baseline (HR = 1.24, 95% CI = 1.08–1.43) was significantly associated with increased CRC risk. BMI trajectory analyses revealed that the CRC risk increased gradually over the three BMI trajectories (HR = 1.11–1.27, P_trend = 0.005) compared with subjects who maintained a normal BMI. Being overweight/obese at the onset of adulthood and BMI trajectories over the lifespan that result in obesity lead to an increased CRC risk.

An inverse association between tea consumption and colorectal cancer risk

Polygenic risk score (PRS) has been demonstrated to be effective in identifying individuals at high risk of developing cancer, but its prognostic value remains unclear. We constructed site-specific PRSs by aggregating the risk effect of independent variants derived from previous genome-wide association studies (GWASs) across 17 cancer types. The Cox proportional hazards model was used to evaluate the association of each PRS with cancer survival, leveraging data from two prospective European cohorts, namely the UK Biobank involving 19,628 incident cases and The Cancer Genome Atlas involving 7079 prevalent cases. The combined PRS (CPRS), determined by merging site-specific PRSs, was further used to assess the prognostic effect of PRS on overall cancer in a sex-specific manner. We discovered that the cancer risk-related PRS was associated with neither overall survival (OS) nor cancer-specific survival (CSS) of each site-specific cancer with an underlying false discovery rate (FDR) P > 0.05, as evidenced by consistent findings from the two cohorts. Furthermore, the fixed-effect meta-analysis of the two cohorts provided no evidence to support for an association between CPRS and overall cancer survival in both males [OS: hazard ratio (HR)_meta = 1.00, P_meta = 0.760; CSS: HR_meta = 1.01, P_meta = 0.447] and females (OS: HR_meta = 0.97, P_meta = 0.067; CSS: HR_meta = 0.96, P_meta = 0.054). Similar results were observed across multiple sensitivity analyses. Our findings indicate that the risk-specific PRS might not be a clinically useful tool in cancer prognosis prediction and further studies focusing on the development of polygenic prognostic score are warranted. This project was funded by the National Natural Science Foundation of China (82173601 and 82073631), and Priority Academic Program Development of Jiangsu Higher Education Institutions (Public Health and Preventive Medicine).

The different incidence of colorectal cancer between the sexes suggests that sex hormones may be involved in the susceptibility to colorectal cancer. The association between sex hormones and genetic variants in hormone metabolic pathways and the colorectal cancer risk remains unclear. We detected sex hormone levels in plasma from colorectal cancer patients and controls in males by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We evaluated the clinical significance of sex hormones on colorectal cancer diagnosis with the area under the receiver operating characteristic curve (AUC). The role of genetic variants in hormone metabolic pathways in the colorectal cancer risk was assessed by a logistic regression model. The biological functions were detected by luciferase reporter assays and cell behavior experiments. We found that 2-methoxyestrone (2-MeO-E1) was highly expressed in cases (P_FDR = 3.48 × 10^-19). The expression of 2-MeO-E1 in plasma showed improved accuracy for predicting colorectal cancer (AUC = 0.88). In the 2-MeO-E1 metabolic pathway, rs165599 in COMT was significantly associated with an increased risk of colorectal cancer (P = 0.009). Mechanistically, we found that the rs165599 G allele could decrease the binding ability of miR-22-3p to the COMT 3'-UTR. Furthermore, knockdown of COMT inhibited cell proliferation, induced cell apoptosis and arrested the cell cycle in the G1 phase. This is the first study to show that 2-MeO-E1 and a genetic variant in COMT contribute to the susceptibility to colorectal cancer. These results shed light on the different incidence of colorectal cancer between the sexes.