HER-2/neu gene amplification in gastric adenocarcinoma and its relationship with clinical and pathological findings

Prevalence of HER2 expression and its association with clinicopathological parameters in gastric and gastroesophageal junction adenocarcinoma: A 10?year experience of an academic center

HER2 overexpression is a marker for targeted therapy in adenocarcinoma of the gastroesophageal junction (GEJ) and stomach. The present study aimed to evaluate the frequency of HER2 overexpression with reference to clinicopathological characteristics in subjects from King Abdulaziz University Hospital, Jeddah, Saudi Arabia over a 10-year period. A retrospective cross-sectional study was conducted on all biopsy and resection specimens diagnosed with either gastric cancer (GC) or GEJ adenocarcinomas from patients between January 2014 and December 2023 that had a final pathology report. Demographic characteristics of 122 patients, including age and sex, were collected, along with pathological details such as tumor grade, histological subtype and HER2 status. χ2 test was used to analyze the association between collected clinicopathological characteristics and HER2 status of the tumor. Most patients were aged 40-60 years. Males constituted 66% of the patients, and the ethnic distribution between Saudi and non-Saudi was almost equal. The most common subtype of cancer was the intestinal type (49%), and the majority of cases were poorly differentiated (64%). HER2 status was assessed in only 61% of cases, with 13.5% showing gene amplification. There was no significant association found between HER2 status and clinicopathological features.

Autologous tumor‑derived microvesicles influence gene expression profiles and enhance protumorigenic chemotactic potential, signal transduction and cellular respiration in gastric cancer cells

Tumor‑derived microvesicles (TMVs) interact with a variety of different cell types within the immune system, including lymphocytes, monocytes, dendritic cells and tumor cells that they have originated from. In the present study, the effects of autologous‑TMVs (auto‑TMVs) on gene expression, chemotaxis, intercellular signaling and cellular metabolism were examined in cells of the gastric cancer (GC) cell line 1415 (GC1415). The effects of auto‑TMVs on mRNA gene expression in GC1415 cells were assessed using pathway‑focused PCR arrays. A chemotaxis assay was performed using the HoloMonitor M4 System. Signaling pathways were evaluated using western blot analysis, and cellular respiration was measured using the Seahorse XF Cell Mito Stress Test. Exposure of the GC1415 cells to auto‑TMVs led to the overexpression (75 genes) and underexpression (96 genes) of genes that are associated with signal transduction, metabolism, chemotaxis, angiogenesis and metastasis. The auto‑TMVs were indicated to induce chemotaxis and activate the PI3K/AKT signaling pathway in GC1415 cells. However, the MAPK/ERK signaling pathway was not indicated to be activated. Furthermore, studies on cellular respiration in GC1415 cells exposed to auto‑TMVs demonstrated a metabolic shift to glycolysis. The results of the current study thus indicate that auto‑TMVs may exert an effect on tumor cell function.

Prevalence of HER2 Expression and Its Correlation with Clinicopathological Parameters in Gastric or Gastroesophageal Junction Adenocarcinoma in North-East Indian Population

Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicated in advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2 positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-East India and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of 68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examination from September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational (epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved, standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters. Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantly higher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patients with well differentiated histology and was more common in patients with stage II and III diseases, but neither of the associations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours (56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patients with locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlated significantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expression is recommended to provide a therapeutic advantage in Indian patients.