Correlation of OPN gene expression with proliferation and apoptosis of ovarian cancer cells and prognosis of patients

An integrated bioinformatic investigation of focal adhesion-related genes in glioma followed by preliminary validation of COL1A2 in tumorigenesis

Focal adhesions (FAs) allow cells to contact the extracellular matrix, helping to maintain tension and enabling signal transmission in cell migration, differentiation, and apoptosis. In addition, FAs are associated with changes in the tumor microenvironment (TME) that lead to malignant progression and drug resistance in tumors. However, there are still few studies on the comprehensive analysis of focal adhesion-related genes (FARGs) in glioma. Expression data and clinical information of glioma samples were downloaded from public databases. Two distinct molecular subtypes were identified based on FARGs using an unsupervised consensus clustering algorithm. A scoring system consisting of nine FARGs was constructed using integrated LASSO regression and multivariate Cox regression. It not only has outstanding prognostic value but also can guide immunotherapy of glioma patients, which was verified in TCGA, CGGA, GSE16011, and IMvigor210 cohorts. The results of bioinformatics analysis, immunohistochemistry staining, and western blotting all revealed that the expression of COL1A2 was up-regulated in glioblastoma and related to poor prognosis outcomes in patients from public datasets. COL1A2 promotes the proliferation, migration, and invasion of glioblastoma cells. A positive correlation between COL1A2 and CD8 was determined in GBM specimens from eight patients. Moreover, the results of cell co-cultured assay showed that COL1A2 participated in the killing of GBM cells by Jurkat cells. Our study indicates that the FARGs have prominent application value in the identification of molecular subtypes and prediction of survival outcomes in glioma patients. Bioinformatics analysis and experimental verification provide a direction for further research on FARGs.

OPN Promotes Cell Proliferation and Invasion through NF-κB in Human Esophageal Squamous Cell Carcinoma

Background

Osteopontin (OPN) is a phosphorylated glycoprotein. There is increasing evidence that the OPN gene played a major role in the progression of solid organ tumors. However, few studies have clarified how OPN regulated the functional role of human esophageal squamous cell carcinoma (ESCC). This study was designed to investigate the effect of OPN in esophageal squamous cell carcinoma.

Methods

First, we screened Eca-109 and KYSE-510 cells to construct OPN silencing and overexpression models. Endogenous OPN of Eca-109 and KYSE-510 were knocked down or overexpressed using small interfering RNAs. QRT-PCR, Western blot, flow cytometry, and CCK-8 were used to detect the function of Eca-109 and KYSE-510 cells. Tumor formation in nude mice was used to measure tumor growth after OPN inhibition.

Results

Eca-109 and KYSE-510 cells contain the si-OPN arrest cell cycle in the S-phase and increase apoptosis. These changes were OPN downregulation of the NF-κB pathway that significantly reduced the protein levels of TNF-α, IL-1β, and p-p65. However, the activity of Eca-109 and KYSE-510 cells was enhanced in OPN overexpressing cells. Then, the in vivo tumor formation experiment in nude mice showed that the tumor volume and weight of nude mice after silencing OPN were significantly reduced.

Conclusion

This study contributed to understanding the vital role of OPN in ESCC development and progression. This could be a promising molecular target for developing new ESCC diagnostic and therapeutic strategies.

SPP1 Regulates Radiotherapy Sensitivity of Gastric Adenocarcinoma via the Wnt/Beta-Catenin Pathway

Purpose

Radiotherapy has been widely applied for the treatment of locally advanced and metastatic gastric adenocarcinoma (GAC). The aberrant expression of secreted phosphoprotein 1 (SPP1) is involved in radiosensitivity in a variety of cancers. The present study aims to characterize the clinical significance of SPP1 expression in GAC and its role and underlying mechanism of radiosensitivity.

Methods

The SPP1 expression in GAC tissues and pericarcinomatous tissues was determined by QRT-PCR and immunohistochemistry, and the SPP1 expression in GAC cell lines (BGC823, AGS, and SGC7901) and normal human gastric epithelial cell line (GES-1) was determined by western blot. T-test, one-way ANOVA, Cox regression model, and Kaplan–Meier plotter were applied to further assess the association between SPP1 expression and the prognosis of the patients with GAC. After irradiation and transfection with si-SPP1 combined with or without Wnt/β-catenin pathway inhibitor (XAV939), western blot, transwell, flow cytometry, and TOP-flash reporter assay were applied to detect DNA damage, invasion, apoptosis, cell cycle, and activation of Wnt/β-catenin pathway, respectively.

Results

SPP1 mRNA and protein levels in GAC tissues were both dramatically higher than those in pericarcinomatous tissues. SPP1 overexpression was positively associated with tumor size, nodal status, and histological grade of GAC patients. SPP1 overexpression, depth of invasion, and nodal status were independent prognostic factors for the patients. High SPP1 expression was negatively related to the overall survival in patients with GAC. We found that SPP1 knockdown enhanced the radiosensitivity of GAC cell lines (AGS and SGC7901). Increasing H2AX phosphorylation, apoptosis and G2/M phase arrest, and decreasing invasion were observed after the administration of si-SPP1 and irradiation. Radiosensitivity of SPP1 was mainly dependent on the Wnt/β-catenin signal pathway. XAV939 could enhance these phenomena induced by irradiation combined with SPP1 knockdown.

Conclusion

This study demonstrates that SPP1 suppresses Wnt/β-catenin signaling to enhance the radiosensitivity of GAC via inhibiting invasion and accelerating DNA damage, G2/M phase arrest, and apoptosis.

Melittin suppresses growth and induces apoptosis of non-small-cell lung cancer cells via down-regulation of TGF-β-mediated ERK signal pathway

The purpose of this study was to investigate the anti-cancer effect of melittin on growth, migration, invasion, and apoptosis of non-small-cell lung cancer (NSCLC) cells. This study also explored the potential anti-cancer mechanism of melittin in NSCLC cells. The results demonstrated that melittin suppressed growth, migration, and invasion, and induced apoptosis of NSCLC cells in vitro. Melittin increased pro-apoptotic caspase-3 and Apaf-1 gene expression. Melittin inhibited tumor growth factor (TGF)-β expression and phosphorylated ERK/total ERK (pERK/tERK) in NSCLC cells. However, TGF-β overexpression (pTGF-β) abolished melittin-decreased TGF-β expression and pERK/tERK in NSCLC cells. Treatment with melittin suppressed tumor growth and prolonged mouse survival during the 120-day observation in vivo. Treatment with melittin increased TUNEL-positive cells and decreased expression levels of TGF-β and ERK in tumor tissue compared to the control group. In conclusion, the findings of this study indicated that melittin inhibited growth, migration, and invasion, and induced apoptosis of NSCLC cells through down-regulation of TGF-β-mediated ERK signaling pathway, suggesting melittin may be a promising anti-cancer agent for NSCLC therapy.

Integrin-Linked Kinase Is a Novel Therapeutic Target in Ovarian Cancer

OBJECTIVE

The objective of this study is to identify and validate novel therapeutic target(s) in ovarian cancer.

BACKGROUND

Development of targeted therapeutics in ovarian cancer has been limited by molecular heterogeneity. Although gene expression datasets are available, most of them lack appropriate pair-matched controls to define the alterations that result in the transformation of normal ovarian cells to cancerous cells.

METHODS

We used microarray to compare the gene expression of treatment-naïve ovarian cancer tissue samples to pair-matched normal adjacent ovarian tissue from 24 patients. Ingenuity Pathway Analysis (IPA) was used to identify target pathways for further analysis. Integrin-linked kinase (ILK) expression in SKOV3 and OV90 cells was determined using Western blot. ILK was knocked down using CRISPR/Cas9 constructs. Subcutaneous xenograft study to determine the effect of ILK knockdown on tumor growth was performed in NOD SCID gamma mice.

RESULTS

Significant upregulation of the ILK pathway was identified in 22 of the 24 cancer specimens, identifying it as a potential player that could contribute to the transformation of normal ovarian cells to cancerous cells. Knockdown of ILK in SKOV3 cells resulted in decreased cell proliferation and tumor growth, and inhibition of downstream kinase, AKT (protein kinase B). These results were further validated using an ILK-1 chemical inhibitor, compound 22.

CONCLUSION

Our initial findings validate ILK as a potential therapeutic target for molecular inhibition in ovarian cancer, which warrants further investigation.