Molecular Diagnostics in Esophageal and Gastric Neoplasms: 2018 Update

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.

SKA1 overexpression is associated with the prognosis of esophageal squamous cell carcinoma and regulates cell proliferation and migration

Spindle and kinetochore‑associated protein 1 (SKA1), a microtubule‑binding subcomplex of the outer kinetochore, is essential for complete chromosomal separation. SKA1 has been suggested as a potential biomarker for various types of cancer. However, the exact role of SKA1 in esophageal squamous cell carcinoma (ESCC) remains unclear. The present study investigated whether SKA1 affects the biological behavior of ESCC. The expression of SKA1 in ESCC tissues was measured using immunohistochemistry and reverse transcription‑quantitative polymerase chain reaction. In addition, a SKA1‑silencing lentivirus was constructed, which was transfected into TE‑1 cells to establish stable SKA1‑knockdown TE‑1 cells. Proliferation was analyzed using a Celigo image cytometer and a MTS assay. Cell cycle progression and apoptosis were analyzed by flow cytometry, while cell migration was assessed using a Transwell assay. SKA1 was significantly overexpressed in ESCC tissues, and SKA1 overexpression was significantly associated with differentiation, pathological N stage and pathological tumor‑node‑metastasis stage. SKA1 was determined to be an independent prognostic factor for ESCC. Furthermore, SKA1 was significantly overexpressed in ESCC cells, and SKA1‑silencing inhibited cell proliferation and migration, arrested the cell cycle and promoted cell apoptosis. In summary, SKA1 may serve as a potential therapeutic target and prognostic biomarker for ESCC.

WISP2 exhibits its potential antitumor activity via targeting ERK and E-cadherin pathways in esophageal cancer cells

Backgrounds

Emerging evidence has demonstrated that WISP2 is critically involved in cell proliferation, migration, invasion and metastasis in cancers. However, the function of WISP2 in esophageal squamous cell carcinoma (ESCC) is largely unclear. Therefore, we aim to explore the effects and the potential mechanism of WISP2 on proliferation and motility and invasion of ESCC cells.

Methods

Cell proliferation was detected by MTT assay and apoptosis was measured by FACS in ESCC cells after WISP2 downregulation and overexpression. Cell migration and invasion were analyzed by wound healing assay and transwell migration assay, respectively. The expression of ERK-1/2, Slug and E-cadherin was measured by Western blot respectively. IHC was performed to measure the expression of WISP2 in ESCC tissues.

Results

WISP2 overexpression is associated with survival in ESCC patients. WISP2 overexpression inhibited cell growth and induced cell apoptosis, suppressed cell migration and invasion in ESCC cells. Moreover, WISP overexpression retarded tumor growth in mouse model. WISP2 downregulation enhanced cell growth, inhibited apoptosis, promoted cell migration and invasion in ESCC cells. Mechanistically, WISP2 exerts its tumor suppressive functions via regulation of ERK1/2, Slug, and E-cadherin in ESCC cells.

Conclusions

Our findings suggest that activation of WISP2 could be a useful therapeutic strategy for the treatment of ESCC.

A negative feedback loop between long noncoding RNA NBAT1 and Sox9 inhibits the malignant progression of gastric cancer cells

Long noncoding RNAs (lncRNAs) play critical roles in carcinogenesis and progression, and act as important gene expression modulators. Recent evidence indicates that lncRNA neuroblastoma associated transcript 1 (NBAT1) functions as a tumor suppressor in some types of human cancers. However, its functional role in the development of gastric cancer (GC) remains unknown. The aim of this research was to investigate the clinical significance and biological functions of NBAT1 in GC. NBAT1 was found to be significantly down-regulated in GC tissue. Decreased NBAT1 expression was correlated with poor differentiation, higher tumor stage and lymph node metastasis, and poor prognosis. Functional assays showed that NBAT1 inhibited GC proliferation, migration, and invasion. NBAT1 also suppressed proliferation, migration, and capillary tube formation of human umbilical vein endothelial cells (HUVECs). Mechanistically, NBAT1 interacted with Sox9, and reduced its protein stability by promoting it from polyubiquitination and proteasome-dependent degradation. Moreover, we revealed that Sox9 could occupy the NBAT1 promoter to inactivate its transcription. The negative feedback loop of NBAT1 and Sox9 continuously enhanced the suppressive effects. In conclusion, these findings suggest that feedback regulation of NBAT1 and Sox9 served as a critical effector in GC progression.

Recombinant adenovirus-p53 enhances the therapeutic effect of surgery and chemoradiotherapy combination in hypopharyngeal squamous cell carcinomas patients

The purpose of our study was to assess the safety and efficacy of recombinant adenovirus-p53 (rAd-p53) combined with surgery and chemoradiotherapy (CRT) for patients with hypopharyngeal squamous cell carcinomas (HPSCC). This study retrospectively and consecutively collected clinical data of 102 patients with primary HPSCC who were admitted to the Department of Otolaryngology of West China Hospital, Sichuan University in China between March 2010 and December 2015. A retrospective clinical study of 102 patients with HPSCC was carried out from March 2010 to December 2015. All patients were male and were divided into 3 groups based on the treatments they received, including Single Surgery, Surgery + CRT, and Surgery + CRT + rAd-p53. In the Surgery + CRT + rAd-p53 group, rAd-p53 was intratumorally injected on the 1st day preoperatively; peritumorally injected on the 7th day intraoperatively, and on the 21st, 28th, and 35th days postoperatively. Their clinical data were retrospectively collected and analyzed. In our study, for all 102 patients with HPSCC, 16 patients received Single Surgery, 44 patients received Surgery + CRT therapy, and 42 patients received Surgery + CRT + rAd-p53 therapy. In the Surgery + CRT + rAd-p53 group, all patients could tolerate rAd-p53 treatment and no serious side effect was observed. In addition, rAd-p53 application did not increase the side reactions caused by surgery and CRT. Compared with the 3-year overall survival rates of Single Surgery group and Surgery + CRT group, the 3-year overall survival rates of Surgery + CRT + rAd-p53 group was significantly enhanced (P < .05). Similar results were also observed for the 3-year disease-free survival rates. Our results indicate that rAd-p53 therapy may improve the therapeutic effect of patients with HPSCC, and is a safe and effective treatment method for patients with HPSCC. However, further prospective studies with larger sample sizes are needed to validate our findings.

Epstein-Barr virus infection associated with pepsinogens and Helicobacter pylori infection in patients with gastric cancer

BACKGROUND

There is no study reporting the influence of the Epstein-Barr virus (EBV) infection on the biomarkers of gastric function like pepsinogen (PG) I and II in patients with gastric cancer, and the relationship between the infection of EBV and Helicobacter pylori (HP) is unclear. This study focused on these issues.

METHODS

In this study, we detected the serum levels of PGI, PGII, anti-HP (immunoglobulin G) IgG antibodies and EBV DNA load in a total of 189 gastric cancer patients confirmed to be EBV positive or negative in tissue using in situ hybridization of EBV-encoded small RNAs (EBERs).

RESULTS

Compared to 123 EBV negative gastric cancer patients, the 66 patients infected with EBV exhibited significant higher levels of PGI and PGI/II ratio and meanwhile, had remarkably lower levels of anti-HP IgG. The prevalence of HP infection in EBV positive patients was 13.6%, and 52.8% in EBV negative patients. In subsequent analysis concerning the EBV DNA load, the patients were divided into two groups by a cutoff value of 1000 copies/ml. The EBV DNA load showed highly consistent association with PGI, PGI/II ratio and HP.

CONCLUSIONS

EBV infection in situ increased the serum levels of PGI and ratio of PGI/PGII in gastric cancer patients. Moreover, the EBV infection exclusively exists with HP infection in the patients with gastric cancer.