Advances in Helicobacter pylori infection involved in gastric cancer metastasis

Gastric cancer is a common cancer of the gastrointestinal tract, highly occurring in East and Southeast Asian. Roughly more than 50% of the population is exposed to Helicobacter pylori (H. pylori) infection worldwide. H. pylori infection is one of the risk factors for gastric cancer and is strongly associated with the development of gastric cancer. The association between H. pylori infection and metastasis of gastric cancer is still inconclusive but has made some progress. For one thing, H. pylori is colonized in the gastric mucosa. The effect of its key virulence factors, VacA and CagA proteins, keeps H. pylori alive in the stomach for a long time and makes it possible for H. pylori to promote the proliferation, epithelial-mesenchymal transition and metastasis of gastric cancer cells. For another, the tumor microenvironment is the site of interaction between host immune system and tumor. By interfering with the effect of tumor cells and immune cells, enhancing the formation of an acidic and hypoxic environment and altering the differentiation of cells in the tumor microenvironment, H. pylori infection can strengthen immune escape and then facilitate the metastasis of gastric cancer. H. pylori infection has become a global public health problem, and its influence on the evolution of gastric cancer cannot be disregarded. The review addresses the correlation between H. pylori infection and gastric cancer metastasis through both key virulence factors and tumor microenvironment. It will provide reference for clinical and basic research in gastric cancer

Exploratory study of interferon regulatory factor 3 promoting proliferation and invasion related to colorectal cancer cells

Objective·To analyze the relationship between the expression level of interferon regulatory factor 3 (IRF3) in colorectal cancer and its clinicopathological features and prognosis, and to observe the effects of IRF3 overexpression on the proliferation and invasion ability of colorectal cancer cells and the related protein molecular pathways.MethodsThe Cancer Genome Atlas (TCGA) data were downloaded and used to analyze the correlation between expression levels of IRF3 and the prognosis of patients (including renal cell carcinoma, colorectal cancer, hepatocellular carcinoma, and prostate cancer). Immunohistochemistry was used to detect the differences in the expression levels of IRF3 between cancerous tissue and adjacent normal tissues of 10 patients with colorectal/renal cancer. The C-terminal residue sites of the IRF3 protein were modified to construct HEK-293T cells overexpressing the phosphorylated IRF3-5D (396/398/402/404/405-D). At 12 and 24 h of cell culture, treatment with TANK-binding kinase 1 (TBK1) inhibitor was performed, and Western blotting was used to detect the expression levels of IRF3 and p-IRF3 (Ser386) in the cells. RNA sequencing (RNA-seq) was employed to explore the correlation between high expression of IRF3-5D and the expression levels of tumor-related proteins. Colorectal cancer cells CT26 and COLON26 overexpressing wild-type IRF3 (IRF3-WT) and IRF3-5D were construct, and cell proliferation and migration ability were assessed by using cell counting, scratch assay, and clonogenic assay.Results·Analysis of TCGA data suggested that the expression level of IRF3 protein in cancer tissues was positively correlated with poor prognosis in patients. Immunohistochemical analysis of pathological tissues from patients with cancer showed that the expression level of IRF3 was significantly upregulated in colorectal cancer tissues and renal cancer tissues, with protein expression concentrated in the cell nucleus. After treatment with TBK1 inhibitors for 12 and 24 h in cell culture, the expression of p-IRF3 (Ser386) protein in HEK-293T cells decreased. The results of RNA-seq and Western blotting showed that the expression levels of multiple proteins associated with poor prognosis [such as IRF9, programmed cell death 1-ligand 1 (PD-L1), etc.] were significantly upregulated under conditions of high expression of IRF3-5D. Overexpression of IRF3-5D in colorectal cancer cells could significantly enhance the proliferation and migration capabilities of cancer cells.Conclusion·The expression level of IRF3 in colorectal cancer is positively correlated with poor patient prognosis. High expression of IRF3-5D protein in colorectal cancer cells can promote malignant biological behavior of cancer cells. Additionally, IRF3-5D is dependent on the TBK1-mediated activation of the IRF3 activation pathway and upregulates the expression levels of multiple tumor-related proteins

D-mannose: A novel prognostic biomarker for patients with esophageal adenocarcinoma

Metabolomic profiling is a promising approach to identify new biomarkers for cancer prognosis. However, the role of circulating metabolites as prognostic indicators in esophageal adenocarcinoma (EAC) has not been well explored. In this study, we aimed to evaluate the prognostic value of three serum metabolites, d-mannose, l-proline (LP), and 3-hydroxybutyrate (BHBA), which were significantly different between EAC patients and controls, identified through a global and targeted metabolite profiling. We measured the levels of d-mannose, LP, and BHBA in pretreatment serum from 159 EAC patients, using liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) methods. A multivariable Cox model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the association of these metabolites with recurrence and overall survival. We found that serum levels of d-mannose were significantly associated with recurrence and overall survival in EAC patients, whereas levels of LP and BHBA were not. Compared with patients with a low (first tertile) level of d-mannose, those with a high (second plus third tertiles) level had 49% reduced risk of recurrence (HR = 0.51; 95% CI: 0.29-0.91; P = 0.02), and 56% reduced risk of death (HR = 0.44; 95% CI: 0.25-0.77, P \u3c 0.01). The significant association of high d-mannose levels with better prognosis was consistent among patients with early-stage and advancedstage EAC. Our results suggest that serum level of d-mannose may be used as a novel prognostic biomarker for patients with EAC. Further studies in independent populations are warranted to confirm our findings

The deubiquitinating enzyme UCHL1 is a favorable prognostic marker in neuroblastoma as it promotes neuronal differentiation

Abstract Background Neuroblastoma (NB) is the most common pediatric solid tumor that originates from neural crest-derived sympathoadrenal precursor cells that are committed to development of sympathetic nervous system. The well differentiated histological phenotype of NB tumor cells has been reportedly associated with favorable patient outcome. Retinoic acid (RA) can effectively induce NB cell differentiation, thereby being used in the clinic as a treatment agent for inducing the differentiation of high-risk NB. However, the underlying molecular mechanisms of regulating differentiation remain elusive. Methods The correlation between clinical characteristics, survival and the deubiquitinating enzyme ubiquitin C-terminal hydrolase 1 (UCHL1) expression were assessed using a neuroblastic tumor tissue microarray, and then validated in three independent patient datasets. The different expression of UCHL1 in ganglioneuroblastoma, ganglioneuroma and NB was detected by immunohistochemistry, mass spectra and immunoblotting analysis, and the correlation between UCHL1 expression and the differentiated histology was analyzed, which was also validated in three independent patient datasets. Furthermore, the roles of UCHL1 in NB cell differentiation and proliferation and the underlying mechanisms were studied by using short hairpin RNA and its inhibitor LDN57444 in vitro. Results Based on our neuroblastic tumor tissue microarrays and three independent validation datasets (Oberthuer, Versteeg and Seeger), we identified that UCHL1 served as a prognostic marker for better clinical outcome in NB. We further demonstrated that high UCHL1 expression was associated with NB differentiation, indicated by higher UCHL1 expression in ganglioneuroblastomas/ganglioneuromas and well-differentiated NB than poorly differentiated NB, and the positive correlation between UCHL1 and differentiation markers. As expected, inhibiting UCHL1 by knockdown or LDN57444 could significantly inhibit RA-induced neural differentiation of NB tumor cells, characterized by decreased neurite outgrowth and neural differentiation markers. This effect of UCHL1 was associated with positively regulating RA-induced AKT and ERK1/2 signaling activation. What’s more, knockdown of UCHL1 conferred resistance to RA-induced growth arrest. Conclusion Our findings identify a pivotal role of UCHL1 in NB cell differentiation and as a prognostic marker for survival in patients with NB, potentially providing a novel therapeutic target for NB

Fatty acid receptor GPR120 promotes breast cancer chemoresistance by upregulating ABC transporters expression and fatty acid synthesisResearch in context

Background: Chemoresistance is the major cause of neoadjuvant treatment failure in breast cancer patients. Despite recent progress, the mechanism underlying chemoresistance remains to be further defined. Methods: Expression of G protein-coupled receptor 120 (GPR120) was analyzed by immunohistochemistry in the biopsies of primary breast cancer who subsequently underwent preoperative neoadjuvant chemotherapy. In vitro and in vivo loss- and gain-of -function studies were performed to reveal the effects and related mechanism of GPR120 signaling pathway in the chemoresistance of breast cancer cells. Findings: We identified that GPR120, a receptor for long-chain fatty acids, was important for the acquisition of chemoresistance in breast cancer cells. We showed that GPR120 expression was positively associated with clinical response to neoadjuvant chemotherapy in patients. In breast cancer cells, GPR120 enhanced the de novo synthesis of fatty acids that served as GPR120 ligands to activate GPR120 signaling via a feedback mechanism. Upregulated GPR120 signaling rendered cells resistant to epirubicin-induced cell death by upregulating ABC transporters expression and thus decreasing the intracellular accumulation of epirubicin. Akt/NF-κB pathway was responsible for the GPR120-mediated expression of ABC transporters leading to modulation of the concentration of chemotherapeutic drugs in cells. The functional importance of GPR120 in chemoresistance was further validated using epirubicin-treated tumor xenografts, in which we showed that blockade of GPR120 signaling with AH7614 or GPR120-siRNA significantly compromised chemoresistance. Interpretation: Our results highlight that GPR120 might be a promising therapeutic target for breast cancer chemoresistance. Fund: National Natural Science Foundation of China, Ministry of Science and Technology of China, Program of Science and Technology Commission of Shanghai Municipality. Keywords: GPR120, Chemoresistance, ABC transporters, Fatty acid synthesis, Breast cance

Targeting KRAS-mutant stomach/colorectal tumors by disrupting the ERK2-p53 complex

Summary: KRAS is widely mutated in human cancers, resulting in unchecked tumor proliferation and metastasis, which makes identifying KRAS-targeting therapies a priority. Herein, we observe that mutant KRAS specifically promotes the formation of the ERK2-p53 complex in stomach/colorectal tumor cells. Disruption of this complex by applying MEK1/2 and ERK2 inhibitors elicits strong apoptotic responses in a p53-dependent manner, validated by genome-wide knockout screening. Mechanistically, p53 physically associates with phosphorylated ERK2 through a hydrophobic interaction in the presence of mutant KRAS, which suppresses p53 activation by preventing the recruitment of p300/CBP; trametinib disrupts the ERK2-p53 complex by reducing ERK2 phosphorylation, allowing the acetylation of p53 protein by recruiting p300/CBP; acetylated p53 activates PUMA transcription and thereby kills KRAS-mutant tumors. Our study shows an important role for the ERK2-p53 complex and provides a potential therapeutic strategy for treating KRAS-mutant cancer

Potentially functional polymorphisms in the ERCC2 gene and risk of esophageal squamous cell carcinoma in Chinese populations.

ERCC2 is indispensable for nucleotide excision repair pathway, and its functional polymorphisms may be associated with cancer risk. In a large case-control study of 1126 esophageal squamous cell carcinomas (ESCC) patients and 1131 controls, we genotyped two SNPs in ERCC2 (rs238406 G > T and rs13181 T > G) and assessed their associations with ESCC risk. We found a significantly elevated ESCC risk associated with the rs238406 T variant genotypes (adjusted OR = 1.30 and 1.24, 95% CI = 1.02-1.66 and 1.03-1.49 for TG and TG/TT, respectively, compared with GG), particularly in the subgroup of those smoked more than 16 pack-years. Multivariate logistic regression analysis suggested a possible multiplicative gene-environment interaction between rs238406 genotypes and smoking (Pinteraction = 0.026) on ESCC risk. Although no significant risk associations were observed for rs13181, further mini meta-analysis with our and 18 other published studies of 5,012 cases and 8,238 controls found evidence of an association between the rs13181 variant G allele and esophageal cancer risk (TG/GG vs. TT, OR = 1.17; 95% CI = 1.02-1.33). Interestingly, we consistently found a significant correlation between variant genotypes of these two SNPs and ERCC2 mRNA expression. These findings suggest that potentially functional SNPs in ERCC2 may contribute to ESCC risk