New markers and models of premalignancy and the early development of gastric cancer

HSPA6, a novel prognostic and therapeutic biomarker, associated with Ming classification in gastric cancer

OBJECTIVE

This study aimed to explore the clinical relevance of heat shock protein family A member 6 (HSPA6) in gastric cancer (GC) and its effect on GC cell proliferation.

METHODS

HSPA6 mRNA and protein levels were analyzed by bioinformatics, RT-qPCR, western blot and immunohistochemistry. HSPA6 was correlated with clinicopathological variables by the Chi-square test. Kaplan-Meier survival analysis and the univariate and multivariate Cox models were used to assess the prognostic value of HSPA6. Nomogram was used to predict overall survival in patients with GC. Knockdown or over-expression of HSPA6 in GC cell lines was constructed by lentiviral transduction. EdU and CCK-8 assay were used to detect cell proliferation. In vivo mouse tumor models were performed to evaluate the effects of HSPA6 on GC growth.

RESULTS

HSPA6 were significantly upregulated in the GC tissues compared to the normal stomach epithelium and were associated with Ming classification (p < 0.001) and tumor size (p = 0.002). Patients with high expression of HSPA6 showed worse survival compared to the low expression group. HSPA6 was identified to be an independent prognostic biomarker for GC. HSPA6 was functionally annotated with the cell cycle, G2M checkpoint and Hippo pathway. Knockdown of HSPA6 suppressed XGC-1 cell proliferation both in vitro and in vivo. Overexpression of HSPA6 in AGS cells increased proliferation rates, increased the levels of cyclinB1 and YAP and decreased that of phosphorylated YAP. HSPA6 knockdown in the NUGC2 cells had the opposite effect.

CONCLUSIONS

HSPA6 promotes GC proliferation by the Hippo pathway, as a novel prognostic biomarker and potential therapeutic target.

Effect of different oesophagojejunostomy methods on the quality of life of gastric cancer patients after totally laparoscopic total gastrectomy with self-pulling and latter transected technique: study protocol for a randomised trial

INTRODUCTION

Gastric cancer is the fifth most common cancer worldwide and the detection rate of proximal gastric cancer has been increasing. Currently, surgical resection using gastrectomy and proper perigastric lymphadenectomy is the only treatment option to enhance the survival rate of patients with gastric cancer. Laparoscopic total gastrectomy (LTG) is increasingly performed for adenocarcinoma of the oesophagogastric junction. However, totally LTG (TLTG) is only performed by a few surgeons due to difficulty associated with oesophagojejunostomy (OJ), in which there is no consensus on a standardised anastomosis technique. We propose a randomised trial to compare functional end-to-end anastomosis (FETE) and side-to-side anastomosis (Overlap) for OJ.

METHODS AND ANALYSIS

A prospective, randomised, open-label, single-centre, interventional trial has been designed to evaluate the quality of life (QoL) outcomes and safety of FETE and Overlap, with a 1-year follow-up as the primary endpoint. The trial began in 2020 and is scheduled to enrol 96 patients according to a previous sample size calculation. Patients were randomly allocated to the FETE or Overlap groups with a follow-up of 1 year to assess QoL after the procedure. All relevant clinical data including biological markers were collected. The primary indicator is the D-value between the postoperative and preoperative QoL. Student's t-tests will be used to compare continuous variables, while χ² tests or Fisher's exact tests will be used to compare categorical variables. Statistical analysis will be performed with SPSS V.23.0 statistical software. A p<0.05 will be considered statistically significant.

ETHICS AND DISSEMINATION

This study has been approved by the Hospital Institutional Review Board of Huashan Hospital, Fudan University (2020-1055). The results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2000035583.

HOXB13 promotes gastric cancer cell migration and invasion via IGF-1R upregulation and subsequent activation of PI3K/AKT/mTOR signaling pathway

AIMS

This study aimed at exploring HOXB13 expression and function in gastric cancer (GC), and the underlying molecular mechanism.

MATERIALS AND METHODS

HOXB13 and fat mass and obesity-associated protein (FTO) expression in GC and non-GC tissues of GC patients were analyzed using Gene Expression Profiling Interactive Analysis (GEPIA) and verified by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting. The regulatory relationship between FTO and HOXB13 was verified via RT-qPCR, methylated RNA immunoprecipitation sequencing (MeRIP-seq), and double luciferase reporter gene assay. The effects of HOXB13 and FTO on proliferation, invasion, and migration of GC cells were studied using EdU and Transwell assays.

KEY FINDINGS

HOXB13 and FTO expression was abnormally high in GC tissues and cell lines, with no significant correlation between HOXB13 and FTO expression and the prognosis of GC patients. Inhibiting FTO expression in GC cells decreased HOXB13 methylation and upregulated HOXB13 expression. Inhibiting HOXB13 and FTO expression suppressed GC cell proliferation, migration, and invasion. Decreased HOXB13 expression suppressed PI3K/AKT/mTOR signaling pathway activity, while atypical HOXB13 expression promoted it. A probable downstream target of HOXB13 was insulin-like growth factor 1 receptor (IGF-1R); a decrease in IGF-1R relieved GC cell migration, invasion, and proliferation and inhibited PI3K/AKT/mTOR signaling pathway activity promoted by atypical HOXB13 expression.

SIGNIFICANCE

HOXB13 and FTO expression is elevated in GC. FTO suppresses HOXB13 methylation; FTO and HOXB13 expression promotes GC cell proliferation, migration, and invasion. HOXB13 expression intensifies GC invasion through PI3K/AKT/mTOR signaling via IGF-1R. HOXB13 and associated signaling pathways can be effective targets for GC therapy.