'All action no talk': the role of HER2/neu in adjuvant therapy choice for gastric cancer

Photothermal and gene therapy combined with immunotherapy to gastric cancer by the gold nanoshell-based system

BACKGROUND

The gastric cancer is the second most malignant tumor in the world. HER-2 is one of the key targets for the gastric cancer therapy. Anti-HER-2 antibodies like trastuzumab, exhibits the satisfactory therapeutic effect in clinical. However, the drug resistance problem limits its application.

METHOD

In this study, we develop a gold nanoshell (Gold Nanoshell) drug carrier for delivery and selective photo-thermal release of genes which target HER-2 and immunologic adjuvant CPG sequence in gastric tumor cells. The drug delivery system generated a multidimensional treatment strategy which includes gene-, immune- and photothermal-therapy.

RESULTS

The whole gold nanoshell drug delivery system exhibits the well gene transduction ability and combined treatment effect. Both in vitro and in vivo results demonstrate the multiple therapeutic effects of the drug delivery system is better than the monotherapy.

CONCLUSIONS

This study indicates the multiple combined therapy based on the gold nanoshell system would be a promising translational treatment for gastric cancer.

HER2 positivity in gastric and esophageal adenocarcinoma: clinicopathological analysis and comparison

PURPOSE

Primary tumor classification of gastric or esophageal cancer has changed significantly with recent alterations of the tumor-node-metastasis (TNM) staging system. Considering these alterations, human epidermal growth factor receptor 2 (HER2) positivity rates were determined and compared in gastric and esophageal adenocarcinoma. Additionally, HER2 positivity in relation to other clinicopathological characteristics was evaluated.

METHODS

A total of 321 patients with histologically confirmed invasive gastric or esophageal adenocarcinoma were examined for HER2 by immunohistochemy (IHC) and chromogenic in situ hybridization (CISH). IHC 3+ or IHC 2+/CISH-positive tumors were considered HER2 positive. Clinicopathological characteristics were retrospectively retrieved from the patient records.

RESULTS

HER2 positivity was found in 50 of 321 patients (15.6 %). In univariate and multivariate logistic models, HER2 positivity rates were significantly higher in esophageal primary tumors (esophageal 25.0 % vs. gastric 7.4 %) and in intestinal histological tumor type (intestinal 22.6 % vs. diffuse/mixed 5.7 %). No significant differences in HER2 positivity were found between males and females, age below and above 65 years, biopsies and surgical specimens or advanced and early-stage disease. Using the 7th TNM edition, many tumors (30.5 % of all included tumors and 64.5 % of all esophageal primary tumors) previously classified as gastric cancer are now classified as esophageal cancer.

CONCLUSIONS

HER2 positivity occurs in 15.6 % of invasive gastroesophageal adenocarcinoma in Western patients, of which the majority is esophageal primary tumors and of the intestinal tumor type. With the introduction of the 7th TNM edition, a large number of tumors previously classified as gastric are now classified as esophageal tumors instead, with relatively high HER2 positivity rates in these esophageal primary tumors.

Pathologic diagnostics of HER2 positivity in gastroesophageal adenocarcinoma

OBJECTIVES

The human epidermal growth factor receptor 2 (HER2) oncogene shows overexpression in 15% to 30% of gastroesophageal adenocarcinomas. Targeted anti-HER2 therapy with trastuzumab has been recently validated in advanced gastric and gastroesophageal junction cancer treatment. A standardized modified scoring system was recently introduced for gastroesophageal HER2 scoring. We aimed to validate this scoring system, including an analysis of interobserver variability of immunohistochemistry (IHC) scoring.

METHODS

In total, 323 patients with histologically confirmed invasive gastric or esophageal adenocarcinoma were examined for HER2 by IHC and chromogenic in situ hybridization (CISH). IHC 3 + or IHC 2 +/CISH positive tumors were considered HER2 positive. Interobserver variability on IHC scoring using the currently standard modified HER2 scoring system was determined among three clinical pathologists. Clinicopathologic characteristics were retrospectively retrieved from the patient records.

RESULTS

HER2 positivity was found in 50 (15.5%) of 323 patients. Interobserver agreement on IHC scoring was high (κ = 0.78). Most disagreement was found in diffuse or mixed tumor types and in weak to moderate stained samples (IHC 2 +). The HER2 IHC scoring system is sensitive in differentiating HER2 status before ISH.

CONCLUSIONS

The currently used standardized HER2 scoring system is an excellent, clinically applicable method to establish HER2 status in appropriately educated and trained pathologists.