Methods and significance of the combined detection of HER2 gene amplification and chemosensitivity in gastric cancer

Significance of concurrent evaluation of HER2 gene amplification and p53 and Ki67 expression in gastric cancer tissues

OBJECTIVE

The primary objective of this study is to explore the significance of concurrent evaluation of HER2 gene amplification and p53 and Ki67 expression in gastric cancer tissues.

METHODS

Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) methodologies were used to detect HER2 gene amplification, as well as the expression levels of HER2, p53, and Ki67 proteins, across a group of 78 gastric cancer cases.

RESULTS

The expression rate of the HER2 protein was determined to be 43.6% (34/78), with 17.9% (14/78) categorized as HER2 protein 3 + , 14.1% (11/78) as HER2 protein 2 + , and 11.5% (9/78) as HER2 protein 1 + . Using FISH technology, the HER2 gene amplification rate was identified as 19.2% (15/78), including 3 cases of HER2 gene cluster amplification, 5 cases of large granular amplification, 4 cases of punctate amplification, and 3 cases of high polysomy. The positive rate of p53 in gastric cancer cells was 52.6% (41/78), with 62.8% (49/78) of patients exhibiting a ki67 proliferation index ≤ 30, and 37.2% (29/78) accounting for a ki67 proliferation index > 30. The expression rates of the HER2 gene, p53, and ki67 in gastric cancer tissues were significantly associated with both gastric cancer staging and lymph node metastasis (P < 0.05).

CONCLUSION

The HER2 gene amplification rate and gene copy number exhibit a positive correlation with the expression rates of p53 and ki67. Combining these assessments can provide crucial insights into the assessment of metastatic potential, disease progression, and prognosis of gastric tumor cells. This holds paramount importance in steering the formulation of individualized treatment strategies.

Assessing clinical pathological characteristics and gene expression patterns associated with hepatoid adenocarcinoma of the stomach

OBJECTIVE

The objective of this study is to assess the clinical pathological attributes of Hepatoid Adenocarcinoma of the Stomach (HAS) and to delineate the differential diagnostic considerations about it.

METHOD

The investigation involved analyzing 31 HAS cases using histomorphological assessment, immunohistochemical profiling, and relevant gene detection methodologies.

RESULTS

Among the 31 HAS cases, 9 (29.0%) were of trabecular hepatoid adenocarcinoma of the stomach, 7 (22.6%) were of glandular hepatoid adenocarcinoma of the stomach, 4 (12.9%) were of nesting hepatoid adenocarcinoma of the stomach, 3 (9.7%) were of clear cell hepatoid adenocarcinoma of the stomach, and 8 (25.8%) were of diverse hepatoid adenocarcinoma of the stomach. Of these 31 cases, 24 were male, accounting for 77.4% of the cases. Serum alpha-fetoprotein (AFP) levels were notably elevated, with radioimmunoassay results reaching 1240 ng/ml; 28 out of 31 cases had AFP levels below 25 µg/l, accounting for 90.3%. Related genes: HER2 protein indicated positive expression on the cell membrane in 35.5% (11/31) of the cases; HER2 gene amplification detected by the FISH technique was 12.9% (4/31). Tumoral stromal lymphocytes exhibited a PD-1 positive expression rate of 58.1% (18/31). In gastric cancer tissues, the PD-L1 positive rate was 45.1% (14/31).

CONCLUSION

HAS represents a distinctive subtype of gastric cancer with a propensity for mimicking other forms of tumors, underscoring the significance of discerning its unique histopathological attributes for accurate differential diagnosis and tailored therapeutic interventions.

Histopathological features of glandular atrophy of the lamina propria of the gastric mucosa during its occurrence and development

OBJECTIVE

To explore the histopathological features of glandular atrophy of the lamina propria of gastric mucosa during its occurrence and development.

METHOD

We performed detailed histological observation and immunohistochemical examination on the endoscopic biopsy and ESD endoscopic resection specimens of 896 patients with glandular atrophy of the lamina propria of gastric mucosa. The EnVision two-step method was used for immunohistochemical staining, and the slices were incubated with primary antibody CK7, CK20, villin, CDX2, MUC5AC, MUC6, p53 and ki-67. Hematoxylin staining was performed and observed under the microscope and statistically analyzed.

RESULTS

In the initial stage of glandular atrophy of the lamina propria, the proliferation area of the deep gastric pits, and the isthmus and neck of the gastric glands are characterized by roughly normal structure of the glandular structure, increased mesenchyme, and widened space between glands. Subsequently, the gland becomes smaller in volume and less in number, especially at the base, in the gastric glandular part of the gastric unit. The disease at this stage has higher incidence, and occurs more often in the elderly who account for 64.0% (573/896) of our study group. The disease in this stage may exhibit some lesions that are physiologic (age-related degeneration) while others are pathological. Therefore, this condition is called simple glandular atrophy of the lamina propria of the gastric mucosa. When the gastric mucosal epithelium is subjected to infection or repeated infections, chemical stimuli, immune factors, and genetic factors, it can lead to the proliferation and transformation of stem cells in the proliferation area of the deep gastric pits, and the isthmus and neck of the gastric glands, forming single ducts, multiple ducts, or a proliferation of patchy cells. Then, atypical hyperplasia (intraepithelial neoplasia) presents, finally leading to gastric adenocarcinoma.

CONCLUSION

Understanding the histopathological characteristics of glandular atrophy of the lamina propria of gastric mucosa is of great significance in controlling the occurrence and development of gastric cancer.

Clinicopathological features and differential diagnosis of gastric pleomorphic giant cell carcinoma

The aim of this study was to investigate the clinicopathological features and differential diagnosis of gastric pleomorphic giant cell carcinoma. Histopathology, immunohistochemistry, and human epidermal growth factor receptor 2 (HER2) gene testing were conducted for seven cases of gastric pleomorphic giant cell carcinoma. In histomorphological terms, all seven cases involved pleomorphic giant cell carcinoma, accounting for more than 10% of the entire tumor, with pleomorphic spindle cells and giant cells mixed with various histomorphological structures of adenocarcinoma with high, intermediate, and low differentiation. There was large heterogeneity in the HER2 protein expression and HER2 gene amplification in the gastric pleomorphic giant cell carcinoma, and both levels of HER2 were focal in three cases, accounting for 42.9% (3/7). The mismatch repair gene proteins MLH1, MSH2, PMS2, and MSH6 were positive. Routine immunohistochemical markers, i.e., pan-cytokeratin, epithelial membrane antigen, villin, caudal-type homeobox 2, E-cadherin, and p53, were positive in the gastric pleomorphic giant cell carcinoma, while vimentin, calponin, smooth muscle actin, nestin, S-100, cluster of differentiation (CD) 99, desmin, and CD34 were focally expressed in both the spindle and the giant cells, with Ki-67-positive cells accounting for 70-80%. Gastric pleomorphic giant cell carcinoma presents multiple histomorphological features and is easily confused with various tumors. Clarifying the histopathological features of this type of tumor is important for differential diagnosis and precise treatment.

ERCC1 is a potential biomarker for predicting prognosis, immunotherapy, chemotherapy efficacy, and expression validation in HER2 over-expressing breast cancer

Objective

To investigate the relationship between Excision repair cross-complementation 1 (ERCC1) expression, clinicopathological features, and breast cancer prognosis in patients treated with trastuzumab. Further, we aim to explore the immune status of ERCC1 in breast cancer.

Methods

The data were retrieved from publicly available databases like the Cancer Genome Atlas, Therapeutically Applicable Research to Generate Effective Treatments, and the Genotype-Tissue Expression. The data was used to perform differential expression analyses between tumor and normal tissues in pan-cancers, immune-related analysis, homologous recombination deficiency (HRD), tumor mutation burden, and microsatellite instability. A total of 210 patients with HER2 over-expressing breast cancer from the Fourth Hospital of Hebei Medical University between January 2013 to December 2015 were enrolled in the study. Ten adjacent normal tissues were used to study the expression pattern of ERCC1 in normal tissues. Immunohistochemistry was performed to study ERCC1 expression and immune cell infiltration in different status of ERCC1 expression. Further, the correlation between ERCC1 expression, immune cell infiltration clinicopathological features, and the prognosis of patients with breast cancer was analyzed.

Results

The immune analysis revealed a significant correlation between CD8+ T cell, CD4+ T cell, T helper cell, macrophages, mast cells, and ERCC1 expression. Spearman analysis show that ERCC1 expression is related to macrophages and T cells. A close correlation was observed between increased ERCC1 expression and high tumor immune dysfunction and exclusion (TIDE) score as well as HRD. The results revealed a significant correlation among ERCC1, chemotherapy and estrogen receptor (ER; P < 0.05) expression. Univariate survival analysis revealed a significant correlation (P < 0.05) between that ERCC1 and ER expression, blood vessel invasion, and disease-free survival (DFS). ERCC1 and ER expression, tumor size, blood vessel invasion, pathological type, and lymph node metastases significantly correlated (P < 0.05) with overall survival in patients. Multivariate regression analysis revealed that ERCC1 expression and chemotherapy were independent factors that influence DFS. ERCC1 expression and vascular tumor thrombus were independent influencing factors that influence OS.

Conclusion

A correlation was observed between high ERCC1 expression and poor patient prognosis. High ERCC1 expression also influences the efficacy of immunotherapy and chemotherapy.

Systematic Review and Meta-analysis of TP53, HER2/ERBB2, KRAS, APC, and PIK3CA Genes Expression Pattern in Gastric Cancer

Background: With a global prevalence of about 10%, gastric cancer is among the most prevalent cancers. Currently, there has been an ongoing trend toward investigating genetic disruptions in different cancers because they can be used as a target-specific therapy. We aimed to systemically review some gene expression patterns in gastric cancer. Methods: The current systematic review was designed and executed in 2020. Scopus, PubMed, Cochrane Library, Google Scholar, web of knowledge, and Science Direct were searched for relevant studies. A manual search of articles (hand searching), reference exploring, checking for grey literature, and seeking expert opinion were also done. Results: In this review, 65 studies were included, and the expression pattern of HER2/ ERBB2, ER1/Erb1/EGFR, PIK3CA, APC, KRAS, ARID1A, TP53, FGFR2 and MET was investigated. TP53, APC, KRAS, and PIK3CA mutation cumulative frequency were 24.8 (I²=95.05, Q value=525.53, df=26, P<0.001), 7.2 (I²=89.79, Q value=48.99, df=5, P<0.001), 7.8 (I²=93.60, Q value=140.71, df=9, P=0.001) and 8.6 (I²=80.78, Q value=525.53, df=9, P<0.001) percent, respectively. Overexpression was investigated for HER1/ Erb1/EGFR, PIK3CA, APC, KRAS, ARID1A, TP53, CCND1, FGFR2, MET and MYC. The frequency of TP53 and HER2/ERBB2 were 43.1 (I²=84.06, Q value=58.09, df=9, P<0.001) and 20.8 (I²=93.61, Q value=234.89, df=15, P<0.001) percent, respectively. Conclusion: More research is encouraged to investigate the genes for which we could not perform a meta-analysis.

The Histopathological Types and Distribution Characteristics of Gastric Mixed Tumors

Objective

The present study aimed to investigate the histopathological types and distribution characteristics of gastric mixed tumors.

Methods

Detailed histological observations, together with related immunohistochemical and genetic tests, were analyzed on 960 surgically resected samples in 6 hospitals with gastric mixed tumors from May 2017 to May 2021 in this retrospective study.

Results

Epithelial-derived tumors accounted for 80.10% (769/960) of the gastric mixed tumor samples studied, and tumors of different tissue origins accounting for 10.83% (104/960), mesenchymal-derived tumors accounting for 6.25% (60/960), neuroendocrine tumors accounting for 2.40% (23/960), and lymphoma accounting for 0.42% (4/960). The histological types of gastric mixed tumors identified as most commonly were epithelial originated, followed by mixed tumors of different tissue originated, then mixed neuroendocrine, lymphoma, and mesenchymal originated in sequence. The histological number of gastric mixed tumors was ≤ 3 in 83.23% (799/960) of cases and > 4 in 16.77% (161/960) of cases. The mixed histological patterns of gastric mixed tumors were divided into three types: those with tumor cells interspersed with each other, those with incomplete fibrous tissue separation, and those without fibrous tissue separation. The gene target characteristics of gastric mixed tumors were the existence of multi-gene mutation, including human epidermalgrowth factor receptor-2 (HER2) gene amplification, key result areas (K-ras) and platelet-derived growth factor receptor alpha (PDGFRA).

Conclusion

Gastric mixed tumors should be adequately sampled, each piece of tissue should be involved in the morphological proportional division of the tumor, and any independent histological component should be written into the pathological examination report.

Research on the Histological Features and Pathological Types of Gastric Adenocarcinoma With Mucinous Differentiation

Objective

To discuss the histological features, pathological types, and prognosis of gastric adenocarcinoma with mucinous differentiation.

Methods

Specimens of 189 cases of gastric adenocarcinoma with mucinous differentiation were collected for detailed histomorphology, immunohistochemistry, fluorescence in situ hybridization, and follow-up.

Results

In accordance with the morphological and histological structural features of the cancer cells as well as the area ratio of the mucus, gastric adenocarcinoma with mucinous differentiation was divided into four types, namely pure mucinous carcinoma, intraductal papillary mucinous carcinoma, signet ring cell type mucinous carcinoma, and mixed cell type mucinous carcinoma. Based on the macroscopic types according to Bormann's classification, pure mucinous carcinoma was mostly Type I, intraductal papillary mucinous carcinoma was mostly Type II, signet ring cell type mucinous carcinoma was mostly Type IV, and mixed cell type mucinous carcinoma was mostly Type III. The 5-year survival rate was 69.2, 64.2, 0, and 31.5%, respectively. There was a statistical difference in the lymph node metastasis rate and survival rate of the four carcinoma types. The invasion features of pure mucinous carcinoma entailed penetrating corrosively in a push-in form, without blood vessel or lymphatic metastasis and with few lymphocytes and lymphatic nodules in the marginal area. Thus, there was little lymph node metastasis and invasion of nerves. The HER2 protein expression rate was 40.2% (76/189), the HER2 gene amplification detected by FISH technology was 16.9% (32/189).

Conclusion

The independent histological type, four subtypes, and histopathological classification of gastric mucinous adenocarcinoma are important for the prognosis evaluation and precise treatment of this disease.

Disruption of Her2-Induced PD-L1 Inhibits Tumor Cell Immune Evasion in Patient-Derived Gastric Cancer Organoids

Simple Summary

HER2 may contribute to immune evasion in gastric cancer that is associated with PD-L1 expression. Autologous organoid/immune cell co-cultures serve as an appropriate in vitro model to study the effects of anti-HER2 targeted therapy in combination with anti-PD1 immune checkpoint inhibition and may be used as an ex vivo tool for precision medicine.

Abstract

(1) Background: The expression of programmed death-ligand 1 (PD-L1), which interacts with programmed cell death protein 1 (PD-1) on cytotoxic T lymphocytes (CTLs), enables tumors to escape immunosurveillance. The PD-1/PD-L1 interaction results in the inhibition of CTL proliferation, and effector function, thus promoting tumor cell evasion from immunosurveillance and cancer persistence. Despite 40% of gastric cancer patients exhibiting PD-L1 expression, only a small subset of patients responds to immunotherapy. Human epidermal growth factor receptor2 (HER2) is one of the critical regulators of several solid tumors, including metastatic gastric cancer. Although half of PD-L1-positive gastric tumors co-express HER2, crosstalk between HER2 and PD-1/PD-L1 in gastric cancer remains undetermined. (2) Methods: Human gastric cancer organoids (huTGOs) were generated from biopsied or resected tissues and co-cultured with CTLs and myeloid-derived suppressor cells (MDSCs). Digital Spatial Profiling (DSP) was performed on FFPE tissue microarrays of numerous gastric cancer patients to examine the protein expression of immune markers. (3) Results: Knockdown of HER2 in PD-L1/HER2-positive huTGOs led to a concomitant decrease in PD-L1 expression. Similarly, in huTGOs/immune cell co-cultures, PD-L1 expression decreased in huTGOs and was correlated with an increase in CTL proliferation which enhanced huTGO death. Treatment with Nivolumab exhibited similar effects. However, a combinatorial treatment with Mubritinib and Nivolumab was unable to inhibit HER2 expression in co-cultures containing MDSCs. (4) Conclusions: Our study suggested that co-expression of HER2 and PD-L1 may contribute to tumor cell immune evasion. In addition, autologous organoid/immune cell co-cultures can be exploited to effectively screen responses to a combination of anti-HER2 and immunotherapy to tailor treatment for gastric cancer patients.

Clinicopathological features and differential diagnosis of gastrofibromatosis-like undifferentiated carcinoma

Objective

To study the clinicopathological features and differential diagnosis of gastrofibromatosis-like undifferentiated carcinoma (GFLUC).

Methods

Three patients with GFLUC underwent histological and immunophenotypic analyses and fluorescence in situ hybridization to detect human epidermal growth factor receptor (HER2) gene amplification.

Results

Among the three patients (2 male [36 and 44 years old], 1 female [58 years old]), two had lesions in the gastric body and one had lesions in the gastric antrum. Histological analysis revealed mixtures of aggressive fibromatosis and undifferentiated carcinoma in all three cases. Highly invasive fibromatous tissue, consisting of fibroblasts, proliferating myofibroblasts, and collagenous fibrous tissues, accounted for >90% of the tumor, with undifferentiated cancerous tissue accounting for <10% scattered in the gaps within the invasive fibromatous tissue, with no glandular ducts or nests. Immunophenotypic analysis showed that the undifferentiated cancerous cells were positive for pan-cytokeratin, CDX2, villin, and p53, while the cytoplasm of invasive fibromatous cells was positive for vimentin, β-catenin, and smooth muscle actin. No HER2 gene amplification was detected.

Conclusions

Unlike other gastric carcinomas, GFLUC shows specific histological, biological, and immunophenotypic characteristics.

Clinicopathological features of tumor mutation burden, Epstein-Barr virus infection, microsatellite instability and PD-L1 status in Chinese patients with gastric cancer

Objectives

Gastric cancer (GC) is the 4th most common type of cancer worldwide. Different GC subtypes have unique molecular features that may have different therapeutic methods. The aim of the present study was to investigate Epstein-Barr virus (EBV) infection, microsatellite instability (MSI) status, the expression of programmed death-ligand 1 (PD-L1) and gene mutations in GC patients.

Methods

The data of 2504 GC patients, who underwent curative gastrectomy with lymphadenectomy at Peking University Cancer Hospital between 2013 and 2018, were reviewed. We analyzed the clinicopathological factors associated with the immunohistochemistry (IHC) profiles of these patients, and genetic alterations were analyzed using next generation sequencing (NGS).

Results

Mismatch repair-deficient (d-MMR) GC patients were found to have a higher probability of expressing PD-L1 (p = 0.000, PD-L1 cutoff value = 1%). In addition, 4 and 6.9% of the 2504 gastric cancer patients were EBV-positive and d-MMR, respectively. The number of MLH1/PMS2-negative cases was 126 (6%), and the number of MSH2/MSH6-negative cases was 14 (0.9%). d-MMR status was associated with a intestinal group (p = 0.012), but not with tumor differentiation. Furthermore, MSI and d-MMR GC status (detected by NGS and IHC, respectively) were consistently high, and the rate of MSI was higher in patients with d-MMR GC. A number of genes associated with DNA damage repair were detected in GC patients with MSI, including POLE, ETV6, BRCA and RNF43. In patients with a high tumor mutation burden, the most significantly mutated genes were LRP1B (79.07%), ARID1A (74.42%), RNF43 (69.77%), ZFHX3 (65.12%), TP53 (58.14%), GANS (51.16%), BRCA2 (51.16%), PIK3CA (51.16%), NOTCH1 (51.16%), SMARCA4 (48.84%), ATR (46.51%), POLE (41.86%) and ATM (39.53%).

Conclusions

Using IHC and NGS, MSI status, protein expression, tumor mutation burden (TMB) and genetic alterations were identified in patients with GC, which provides a theoretical basis for the future clinical treatment of GC.

Targeting kinases with thymoquinone: a molecular approach to cancer therapeutics

Kinases are enzymes that are important for cellular functions, but their overexpression has strong connections with carcinogenesis, rendering them important targets for anticancer drugs. Thymoquinone (TQ) is a natural compound with proven anticancer activities, at least in preclinical studies. TQ can target several kinases, including phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase (MAPK), Janus kinase/signal transducers and activators of transcription (JAK/STAT), polo-like kinase 1 (PLK1), and tyrosine kinase in different cancer cells and animal models. Inhibiting the activity of kinases or suppressing their expression might be among the mechanisms of TQ anticancer activity. In this review, we discuss the role of TQ in kinase regulation in different cancer models.

Kinases and Cancer

Protein kinases are a large family of enzymes catalyzing protein phosphorylation. The human genome contains 518 protein kinase genes, 478 of which belong to the classical protein kinase family and 40 are atypical protein kinases [...].