Her2/neu Protein Expression and Oncogene Amplification in Gastric Carcinoma with Clinico-Pathological Correlation in Egyptian Patients

Study of the Relationship between MMP-2 and MMP-9 and Her2/neu Overexpression in Gastric Cancer: Clinico- Pathological Correlations

Background:

The relationship between the expressions of matrix metalloproteinases with clinico-pathological data on gastric cancer has been investigated in many countries, but this relationship remains unexplored in Iranian patients. Also, the correlation of the MMPs and the HER-2/neu proto-oncogene with other clinic-pathological variables has been evaluated for several other malignancies, but little effort has been made to shed light on the relationship with gastric cancer.

Methods:

We investigated MMP-2 and MMP-9 expression and HERE-2/neu overexpression in 48 gastric cancer patients referred to Afzalipour Hospital, associated with Kerman Medical University. Immunohistochemistry staining with rabbit polyclonal antibodies was used. Data statistical analysis was done by SPSS software (Version 20.0).

Results:

The mean age was 59, most of the patients were male (79.2%), and the average tumor size was larger than 5 centimeters in its greatest diameter. The majority of tumors were of the intestinal subtype and were located in the pyloric and antrum regions (43.8%). Invasion to muscularis properia was seen in 87.5% of the tumors (T3). MMP-2 and MMP-9 were highly expressed in 58.3% and 50% of cases, respectively, and Her-2/neu positivity was 10.4%. MMP-2, MMP-9 and HER-2 were found to have no relation with any clinicopathological parameters.

Conclusion:

According to the results of this study, MMP-2 and MMP-9 were highly expressed in gastric cancer, but there was no significant association with other clinicopathological variables.

Human epidermal growth factor receptor 2 overexpression in gastric and gastroesophageal junction adenocarcinoma in patients seen at the University Teaching Hospital, Lusaka, Zambia

BACKGROUND

There are scanty data on the occurrence of gastric tumours overexpressing human epidermal growth factor receptor 2 (HER2) in Africa.

OBJECTIVE

To assess HER2 protein overexpression in gastric and gastroesophageal junction adenocarcinoma (GGEAC) samples from a single centre in Zambia.

METHODOLOGY

This was a cross-sectional study of formalin-fixed paraffin-embedded blocks with GGEAC. Prepared slides were first stained with Haematoxylin and Eosin and then evaluated for HER2 protein overexpression by immunohistochemistry.

RESULTS

A total of 57 gastric tissues were stained and evaluated for HER2 overexpression. Thirteen (23%) showed overexpression, 41/57 (72%) had negative and 3/57 (5%) had equivocal staining. The equivocal cases were excluded from the final analysis. Of the remaining 54 tissues, 28 (52%) were from females, and 26 (48%) were from males. The mean age was 59 years (SD 15 years). HER2 overexpression was highest in moderately differentiated tumours (p=0.0005). Intestinal type tumours had a higher occurrenc of HER2 overexpression than diffuse or mixed sub-types (p=0.0087). HER2 overexpression was not associated with age (p=0.27), sex (p=1.00) or anatomical location (p=1.00).

CONCLUSION

The occurrence of GGEAC HER2 overexpression in Zambian patients is similar to proportions reported elsewhere, and it is associated with moderately differentiated tumours of the intestinal type.

GEFT protein expression in digestive tract malignant tumors and its clinical significance

Guanine nucleotide exchange factor T (GEFT), a member of the Rho guanine nucleotide exchange factor family, is expressed in a variety of tumors. In the present study, the expression and clinical significance of GEFT in malignant digestive tract tumors was assessed. Tumor and adjacent control samples from 180 patients were tested. Positive GEFT expression rates were 80, 83.33 and 86.67% in esophageal squamous carcinoma (ESCC), gastric carcinoma (GC) and colorectal cancer (CRC), respectively. GEFT expression was associated with diffuse type carcinoma according to the Lauren classification (χ²=12.525, P=0.002) and tumor-node-metastasis (TNM) stages III/IV (χ²=4.033, P=0.045) in GC, and with vessel carcinoma embolus (χ²=7.890, P=0.005) and lymph node metastasis (χ²=5.455, P=0.020) in CRC, but was not associated with other clinicopathological parameters. Patients with high levels of GEFT protein expression had a less favorable outcome compared with patients with low levels of GEFT expression in patients with CRC (χ²=3.876, P=0.049). However, a significant association was not found between GEFT expression and overall survival in patients with ESCC (χ²=0.040, P=0.842) or GC (χ²=0.501, P=0.479). The rate of human epidermal growth factor receptor 2 upregulation in patients with GC was 13.33% and it was associated with nerve invasion (χ²=4.005, P=0.045) and TNM stages III/IV (χ²=5.600, P=0.018). Mismatch repair protein (MMRP) defect was observed in six cases, and the KRAS mutation rate was 26.67% in patients with CRC. GEFT expression was significantly correlated with MMRP (r=-0.285, P=0.027) and KRAS mutation in patients with CRC (r=0.697, P<0.001). These findings revealed frequent GEFT upregulation in malignant digestive tract tumors, which may have promoted tumor development. GEFT expression in CRC may be associated with microsatellite instability and KRAS mutation status, suggesting that GEFT may be a potential therapeutic target for patients with CRC.

HER2 Oncogene Amplification and Immunohistochemical Profiling in Gastric Adenocarcinoma

Background and Objectives: Gastric adenocarcinoma is one of the most common malignant tumors and a major cause of cancer death worldwide, especially in developing countries. Her2/neu gene amplification and protein overexpression in breast cancer is a golden criterion for the targeted therapy with trastuzumab. However, the role of Her2 as a prognostic factor in gastric cancer is still controversial. The purpose of this study was to evaluate the frequency of Her2 oncogene overexpression and concordance between the results for Her2 protein expression and gene amplification. Materials and Methods: A total of 65 retroprospective cases with gastric adenocarcinoma, including biopsy and resected specimens obtained between July 2015 to December 2017, were analyzed. Her2/neu expression was determined by Immuno-histochemistry (IHC). Equivocal and some selected cases were submitted for FISH to detect Her2/neu gene amplification. Results: In the present study, out of 65 patients of gastric adenocarcinoma, there were 50 males and 15 females, with mean age of 54.52 years. The majority of tumors were located within the antropyloric region. We found 27 (41.4%) positivity, scored as IHC 3+ and IHC 2+, and 38 (58.3%) negativity, scored as IHC 1+ and IHC 0. We also evidentiated a significant difference between Her2/neu expression with age (p=0.010) and depth of invasion (p=0.020).Her2/neu gene was amplified only in 13 cases, 4 cases were of Her2/neu (3+) positive, 11 cases (39.3%) Her2/neu (2+) with IHC staining. The concordance rate between the results of IHC and FISH in all 18 cases was 83.3%. Conclusion: IHC detection can be carried out to guide the treatment when FISH detection cannot be performed. Overexpression of Her 2/neu in gastric adenocarcinoma could potentially be used in selecting the patients who can get benefit from the anti-Her2/neu targeted therapy.