Related Experiment Video
Updated: Oct 10, 2025
Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein
Published on: January 16, 2020
[Effects of K-ras gene silence on the expression of oncogenes in HBE cells treated with PM(2.5)]
1School of Public Health, University of South China, Hengyang 421001, China Institute of Environment and Health, Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, China.
Abstract:
Objective: To explore the effects of K-ras gene on the expressions of oncogenes and cancer suppressor genes in human bronchial epithelial (HBE) cells which were exposed to PM(2.5). Methods: According to the mRNA sequence of K-ras gene provided by GenBank in September 2019, interference sequences were designed and synthesized, and the recombinant lentiviral vector was transfected into HBE cell to construct the K-ras gene-silenced cells. HBE cells and K-ras gene-silenced cells were exposed to 10 μg/ml, 50 μg/ml PM(2.5) suspension and 10 μmol/L Cr(6+). Real-time fluorescent quantitative PCR was used to detect the mRNA expression levels of c-myc, c-fos, N-ras, cyclin-D1, p16 and p53 genes, the expression levels of p53 and c-myc proteins were detected by Western blot. Results: In K-ras silenced cell group, K-ras mRNA expression level decreased (80.5%±3.6%) and K-ras protein level decreased (58.9%±4.7%) when compared with the control group (P<0.01) . Compared with the correspoding cell control group without exposure, the mRNA expression levels of c-myc, c-fos, N-ras and cyclin-D1 genes in HBE cell group exposed to different concentrations of PM(2.5), K-ras silenced cell group exposed to different concentrations of PM(2.5), HBE cell group exposed to 10 μmol/L Cr(6+) and K-ras silenced cell group exposed to 10 μmol/L Cr(6+) were increased, the mRNA expressions of p16 and p53 genes were decreased (P<0.01) . Compared with HBE cell group exposed to 10 μg/ml PM(2.5), the mRNA expressions of c-myc, c-fos and p16 genes in K-ras silenced cells exposed to 10 μg/ml PM(2.5) were decreased, and the p53 mRNA level was increased (P<0.01) . Compared with HBE cell group exposed to 50 μg/ml PM(2.5), the mRNA expression levels of c-fos, N-ras, cyclin-D1, p16 and p53 genes in K-ras silenced cell group exposed to 50 μg/ml PM(2.5) were decreased (P<0.01) . Compared with the HBE cell group without exposure, c-myc protein increased and p53 protein decreased in HBE cells exposed to 50 μg/ml PM(2.5) (P<0.05) . Compared with the K-ras silenced cell group without exposure, c-myc protein increased in K-ras silenced cells exposed to 50 μg/ml PM(2.5) (P<0.05) . Conclusion: PM(2.5) can increase the expression levels of oncogenes in HBE cells, and K-ras gene silencing can inhibit the expression levels of oncogenes in HBE cells treated with PM(2.5).
Insights
Exposure to PM2.5 increases oncogene expression in human bronchial epithelial cells. Silencing the K-ras gene can inhibit these oncogenic effects, suggesting K-ras plays a role in PM2.5-induced lung cell changes.
Area of Science:
- Molecular Biology
- Environmental Health
- Oncology
Background:
- Particulate matter 2.5 (PM2.5) is a major air pollutant linked to respiratory diseases.
- The K-ras gene is frequently mutated in human cancers, including lung cancer.
- Understanding the interaction between environmental factors and genetic pathways is crucial for cancer prevention.
Purpose of the Study:
- To investigate the impact of K-ras gene silencing on oncogene and tumor suppressor gene expression in human bronchial epithelial (HBE) cells exposed to PM2.5.
- To elucidate the role of K-ras in the cellular response to PM2.5 exposure.
Main Methods:
- Constructed K-ras gene-silenced HBE cells using lentiviral vectors.
- Exposed HBE cells and K-ras silenced cells to varying concentrations of PM2.5 and Cr(6+).
- Utilized real-time PCR and Western blot to quantify mRNA and protein expression levels of key genes (c-myc, c-fos, N-ras, cyclin-D1, p16, p53).
Main Results:
- K-ras gene silencing significantly reduced K-ras mRNA and protein levels.
- PM2.5 exposure increased the expression of oncogenes (c-myc, c-fos, N-ras, cyclin-D1) and decreased tumor suppressor genes (p16, p53) in HBE cells.
- K-ras gene silencing partially reversed the PM2.5-induced changes in oncogene and tumor suppressor gene expression.
Conclusions:
- PM2.5 exposure promotes oncogene expression in HBE cells.
- K-ras gene silencing demonstrates a protective effect by inhibiting oncogene expression in HBE cells exposed to PM2.5.
- The K-ras gene is implicated in the cellular response to PM2.5-induced genotoxicity and oncogenesis.
More Related Videos
07:48Utilizing Functional Genomics Screening to Identify Potentially Novel Drug Targets in Cancer Cell Spheroid Cultures
Published on: December 26, 2016
10:21Author Spotlight: Exploring the Role of Inflammation in the Co-occurrence of Primary Sjogren's Syndrome and Lung Adenocarcinoma
Published on: September 20, 2024
Related Concept Videos
02:38The Ras Gene
Ras is a...
01:24Small GTPases - Ras and Rho
Three regulatory proteins control their activity:
01:20The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
02:23Abnormal Proliferation