The effect of metabolism-related lifestyle and clinical risk factors on digestive system cancers in East Asian populations: a two-sample Mendelian randomization analysis.

Metabolic factors play a critical role in the development of digestive system cancers (DSCs), and East Asia has the highest incidence of malignant tumors in the digestive system. We performed a two-sample Mendelian randomization analysis to explore the associations between 19 metabolism-related lifestyle and clinical risk factors and DSCs, including esophageal, gastric, colorectal, hepatocellular, biliary tract, and pancreatic cancer. The causal association was explored for all combinations of each risk factor and each DSC. We gathered information on the instrumental variables (IVs) from various sources and retrieved outcome information from Biobank Japan (BBJ). The data were all from studies of east Asian populations. Finally, 17,572 DSCs cases and 195,745 controls were included. Our analysis found that genetically predicted alcohol drinking was a strong indicator of gastric cancer (odds ratio (OR) = 0.95; 95% confidence interval (CI): 0.93-0.98) and hepatocellular carcinoma (OR = 1.11; 95% CI: 1.05-1.18), whereas coffee consumption had a potential protective effect on hepatocellular carcinoma (OR = 0.69; 95% CI: 0.53-0.90). Triglyceride was potentially associated with a decreased risk of biliary tract cancer (OR = 0.53; 95% CI: 0.34-0.81), and uric acid was associated with pancreatic cancer risk (OR = 0.59; 95% CI: 0.37-0.96). Metabolic syndrome (MetS) was associated with esophageal and gastric cancer. Additionally, there was no evidence for a causal association between other risk factors, including body mass index, waist circumference, waist-to-hip ratio, educational levels, lipoprotein cholesterol, total cholesterol, glycine, creatinine, gout, and Graves' disease, and DSCs. The leave-one-out analysis revealed that the single nucleotide polymorphism (SNP) rs671 from the ALDH2 gene has a disproportionately high contribution to the causal association between alcohol drinking and gastric cancer and hepatocellular carcinoma, as well as the association between coffee consumption and hepatocellular carcinoma. The present study revealed multiple metabolism-related lifestyle and clinical risk factors and a valuable SNP rs671 for DSCs, highlighting the significance of metabolic factors in both the prevention and treatment of DSCs.

Helicobacter pylori CagA protein induces gastric cancer stem cell-like properties through the Akt/FOXO3a axis.

The presence of Helicobacter pylori (H. pylori) infection poses a substantial risk for the development of gastric adenocarcinoma. The primary mechanism through which H. pylori exerts its bacterial virulence is the cytotoxin CagA. This cytotoxin has the potential to induce inter-epithelial mesenchymal transition, proliferation, metastasis, and the acquisition of stem cell-like properties in gastric cancer (GC) cells infected with CagA-positive H. pylori. Cancer stem cells (CSCs) represent a distinct population of cells capable of self-renewal and generating heterogeneous tumor cells. Despite evidence showing that CagA can induce CSCs-like characteristics in GC cells, the precise mechanism through which CagA triggers the development of GC stem cells (GCSCs) remains uncertain. This study reveals that CagA-positive GC cells infected with H. pylori exhibit CSCs-like properties, such as heightened expression of CD44, a specific surface marker for CSCs, and increased ability to form tumor spheroids. Furthermore, we have observed that H. pylori activates the PI3K/Akt signaling pathway in a CagA-dependent manner, and our findings suggest that this activation is associated with the CSCs-like characteristics induced by H. pylori. The cytotoxin CagA, which is released during H. pylori infection, triggers the activation of the PI3K/Akt signaling pathway in a CagA-dependent manner. Additionally, CagA inhibits the transcription of FOXO3a and relocates it from the nucleus to the cytoplasm by activating the PI3K/Akt pathway. Furthermore, the regulatory function of the Akt/FOXO3a axis in the transformation of GC cells into a stemness state was successfully demonstrated.

Mitochondrial DNA copy number and cancer risks: A comprehensive Mendelian randomization analysis.

Mitochondrial DNA plays a critical role in the pathophysiology of cancer. However, the associations between mitochondrial DNA copy number (mtDNA-CN) and cancer risk are controversial. Mendelian randomization (MR) analyses were performed using three independent instrumental variables (IVs) to explore potential associations between mtDNA-CN and 20 types of cancer. The three sets of IVs were primarily obtained from participants in the UK Biobank and the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium using different methods. The outcome data of cancers were investigated using summary statistics from the FinnGen cohort. The potential causal associations were evaluated using the MR-Egger regression, weighted median, inverse-variance weighted (IVW), and weighted mode methods. The robustness of IVW estimates was validated using leave-one-out sensitivity analysis. Additionally, a meta-analysis was conducted to pool results from three sets of IVs. The results revealed that genetically predicted mtDNA-CN was not associated with cancer risk (odds ratio = 1.02; 95% confidence interval: 0.95-1.10). Subgroup analyses indicated no causal association between mtDNA-CN and breast, lung, prostate, skin, colorectal, gastric, liver, cervical uteri, esophageal, thyroid, bladder, pancreas, kidney, corpus uteri, ovary, brain, larynx, and anus cancers. It was observed that mtDNA-CN was associated with lip, oral cavity, and testis cancers. However, these results should be interpreted with caution because a small number of patients with lip and oral cavity or testis cancers were included. The comprehensive MR analysis demonstrated that mtDNA-CN is not a suitable biomarker for tumor risk assessment.

Convenient method to improve efficiency of lymph node examination after gastrectomy with D2 lymphadenectomy for gastric cancer.

BACKGROUND: The D2 procedure has been accepted as the standard treatment for advanced gastric cancer (GC) in East Asia. Determination of the number of lymph nodes (LNs) after gastrectomy may influence the pathological stage assessment of lymph node metastasis, significantly influencing prognostic evaluations and formulation of chemotherapy regimens. METHODS: Between January 2020 and January 2022, the medical files of 312 patients with clinical stage T0-4aN0-3M0 gastric cancer were reviewed retrospectively, and the patients were assigned to the normal group (lymph nodes were examined roughly), manual group (lymph nodes were manually examined meticulously), and device group (lymph nodes were examined by device). The clinical and pathologic characteristics, number of lymph nodes harvested, and the time required for lymph node examination was compared. RESULTS: A total of 312 gastric cancer patients (mean age 65.8 ± 10.3 years, 85 females and 227 males) underwent gastrectomy with curative intent at our department. Sex, age, body mass index (BMI), tumor size, clinical TNM stage, and pathologic TNM stage in the three groups showed no statistically significant differences (P > 0.05). The mean number of harvested lymph nodes in the normal, manual, and device group was 24.2, 36.6 and 35.2, respectively, which showed significant differences (P < 0.0001). The mean number of positive lymph nodes in the normal, manual, and device group was 3.5, 3.9 and 3.9, respectively (P = 0.99). The mean time consumption in device group was 15 min while the time consumption in manual group was 52.3 min, which showed a significant difference (P < 0.0001). CONCLUSION: This improved lymph node examination method offers a simple approach that is worth promoting, and it can improve the number of harvested lymph nodes efficiently.

Mitochondrial DNA copy number is associated with Crohn's disease: a comprehensive Mendelian randomization analysis.

Mitochondrial DNA plays a critical role in the pathophysiological process of inflammation. However, the relationship between mitochondrial DNA copy number (mtDNA-CN) and inflammatory bowel diseases (IBD) remains poorly understood. We conducted a comprehensive Mendelian randomization (MR) using three instrumental variables (IVs) to explore the causal associations between mtDNA-CN and IBD, including Crohn's disease (CD), ulcerative colitis (UC). MR-Egger regression, weighted median, inverse-variance weighted (IVW), and weighted mode methods were used to evaluate the potential causal associations. The robustness of the IVW estimates was determined using the leave-one-out sensitivity test. A meta-analysis was conducted to pool the results from the three sets of IVs. Upon analysis, the findings of the current study revealed that genetically predicted mtDNA-CN was not associated with IBD (CD + UC) and UC. The results of MR analyses between mtDNA-CN and CD risk were inconsistent by using three sets of IVs. After a meta-analysis, we found that genetically predicted mtDNA-CN was associated with CD risk (odds ratio = 2.09; 95% confidence interval: 1.37-3.18). This finding was also confirmed by multivariable MR analyses and remained robust when tested with the leave-one-out sensitivity test. In conclusion, genetically predicted mtDNA-CN was found to be associated with CD risk. Therefore, mtDNA levels in the blood could potentially be used as a marker for CD risk assessment. Further studies are needed to elucidate the underlying mechanisms and validate the results of this study.

LncRNA expression signature identified using genome-wide transcriptomic profiling to predict lymph node metastasis in patients with stage T1 and T2 gastric cancer.

BACKGROUND: Lymph node (LN) status is vital to evaluate the curative potential of relatively early gastric cancer (GC; T1-T2) treatment (endoscopic or surgery). Currently, there is a lack of robust and convenient methods to identify LN metastasis before therapeutic decision-making. METHODS: Genome-wide expression profiles of long noncoding RNA (lncRNA) in primary T1 gastric cancer data from The Cancer Genome Atlas (TCGA) was used to identify lncRNA expression signature capable of detecting LN metastasis of GC and establish a 10-lncRNA risk-prediction model based on deep learning. The performance of the lncRNA panel in diagnosing LN metastasis was evaluated both in silico and clinical validation methods. In silico validation was conducted using TCGA and Asian Cancer Research Group (ACRG) datasets. Clinical validation was performed on T1 and T2 patients, and the panel's efficacy was compared with that of traditional tumor markers and computed tomography (CT) scans. RESULTS: Profiling of genome-wide RNA expression identified a panel of lncRNA to predict LN metastasis in T1 stage gastric cancer (AUC = 0.961). A 10-lncRNA risk-prediction model was then constructed, which was validated successfully in T1 and T2 datasets (TCGA, AUC = 0.852; ACRG, AUC = 0.834). Thereafter, the clinical performance of the lncRNA panel was validated in clinical cohorts (T1, AUC = 0.812; T2, AUC = 0.805; T1 + T2, AUC = 0.764). Notably, the panel demonstrated significantly better performance compared with CT and traditional tumor markers. CONCLUSIONS: The novel 10-lncRNA could diagnose LN metastasis robustly in relatively early gastric cancer (T1-T2), with promising clinical potential.

MiRNA-124-3p.1 sensitizes hepatocellular carcinoma cells to sorafenib by regulating FOXO3a by targeting AKT2 and SIRT1.

As a multikinase inhibitor, sorafenib is commonly used to treat patients with advanced hepatocellular carcinoma (HCC), however, acquired resistance to sorafenib is a major obstacle to the effectiveness of this treatment. Thus, in this study, we investigated the mechanisms underlying sorafenib resistance as well as approaches devised to increase the sensitivity of HCC to sorafenib. We demonstrated that miR-124-3p.1 downregulation is associated with early recurrence in HCC patients who underwent curative surgery and sorafenib resistance in HCC cell lines. Regarding the mechanism of this phenomenon, we identified FOXO3a, an important cellular stress transcriptional factor, as the key factor in the function of miR-124-3p.1 in HCC. We showed that miR-124-3p.1 binds directly to AKT2 and SIRT1 to reduce the levels of these proteins. Furthermore, we showed that AKT2 and SIRT1 phosphorylate and deacetylate FOXO3a. We also found that miR-124-3p.1 maintains the dephosphorylation and acetylation of FOXO3a, leading to the nuclear location of FOXO3a and enhanced sorafenib-induced apoptosis. Moreover, the combination of miR-124-3p.1 mimics and sorafenib significantly enhanced the curative efficacy of sorafenib in a nude mouse HCC xenograft model. Collectively, our data reveal that miR-124-3p.1 represents a predictive indicator of early recurrence and sorafenib sensitivity in HCC. Furthermore, we demonstrate that miR-124-3p.1 enhances the curative efficacy of sorafenib through dual effects on FOXO3a. Thus, the miR-124-3p.1-FOXO3a axis is implicated as a potential target for the diagnosis and treatment of HCC.

Hypoxia induces sorafenib resistance mediated by autophagy via activating FOXO3a in hepatocellular carcinoma.

Sorafenib, a multikinase inhibitor, is considered as the only approved drug to cure the advanced hepatocellular carcinoma (HCC); however, the acquired chemoresistance caused by intratumoral hypoxia through sorafenib long term therapy induces sorafenib inefficacy. We demonstrated here that hypoxia significantly attenuated sensitivity of HCC cells to sorafenib treatment and reduced its proliferation. Autophagy was observed in sorafenib-treated HCC cells in hypoxia, and inhibition of autophagy by 3-MA eliminated hypoxia-induced sorafenib resistance. Further study revealed hypoxia-activated FOXO3a, an important cellular stress transcriptional factor, via inducing its dephosphorylation and nuclear location; and FOXO3a-dependent transcriptive activation of beclin-1 was responsible for hypoxia-induced autophagy in HCC cells. Knockout of FOXO3a inhibited the autophagy induced by sorafenib itself in normoxia and significantly enhanced the cytotoxicity of sorafenib in HCC cells; and it also inhibited the hypoxia-induced autophagy and achieved the same effect in sorafenib sensitivity-enhancement in HCC cells as it in normoxia. Finally, knockout of intratumoral FOXO3a significantly enhanced curative efficacy of sorafenib via inhibition of autophagy in xenograft tumors in nude mice. Collectively, our study suggests that FOXO3a plays a key role in regulating hypoxia-induced autophagy in sorafenib-treated HCC, and FOXO3-targeted therapy may serve as a promising approach to improve clinical prognosis of patients suffering from HCC.