Related Experiment Video

Updated: Apr 4, 2026

Analysis of Combinatorial miRNA Treatments to Regulate Cell Cycle and Angiogenesis
11:44

Analysis of Combinatorial miRNA Treatments to Regulate Cell Cycle and Angiogenesis

Published on: March 30, 2019

8.1K

Down-regulation of let-7 microRNA increased K-ras expression in lung damage induced by radon

Zhihai Chen1, Dapeng Wang1, Chao Gu1

  • 1Department of Toxicology, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, School of Public Health, Medical College of Soochow University, Suzhou 215123, China.

Environmental Toxicology and Pharmacology
|August 31, 2015
PubMed

Insights

Radon exposure causes lung damage by altering let-7 microRNA and K-ras expression. This study reveals their role in radon-induced lung tumorigenesis, offering potential for early diagnosis and therapy.

Area of Science:

  • Environmental Health
  • Molecular Biology
  • Oncology

Background:

  • Radon is a known human carcinogen linked to lung cancer.
  • The precise molecular mechanisms of radon-induced lung damage are not fully understood.
  • let-7 microRNA and K-ras are implicated in various cancers, but their role in radon exposure is unexplored.

Purpose of the Study:

  • To investigate the role of let-7 microRNA and K-ras in radon-induced lung damage.
  • To examine histological, cellular, and molecular changes following long-term radon exposure in rats and human bronchial epithelial cells.

Main Methods:

  • Wistar rats and human bronchial epithelial (HBE) cells were exposed to radon.
  • Evaluated lung tissue histology, reactive oxygen species (ROS) production, antioxidant enzyme activity (SOD), and HBE cell clonogenic formation.
  • Assessed let-7 microRNA and K-ras expression at both mRNA and protein levels.
  • Investigated K-ras expression changes in HBE cells transfected with specific let-7 microRNAs.

Main Results:

  • Radon exposure led to severe lung damage in rats.
  • Increased ROS production and clonogenic formation, with decreased SOD activity in HBE cells.
  • Observed down-regulation of let-7 and up-regulation of K-ras in lung tissue and HBE cells.
  • Confirmed K-ras down-regulation in HBE cells with altered let-7 levels.

Conclusions:

  • let-7 microRNA and K-ras are involved in radon-induced lung damage.
  • Findings suggest a potential pathway for radon-induced lung tumorigenesis.
  • These molecular alterations may serve as biomarkers for early diagnosis and therapeutic targets.
Keywords:
K-rasLet-7MicroRNARadon

More Related Videos

The Soft Agar Colony Formation Assay08:01

The Soft Agar Colony Formation Assay

Published on: October 27, 2014

114.4K
Utilizing 18F-FDG PET/CT Imaging and Quantitative Histology to Measure Dynamic Changes in the Glucose Metabolism in Mouse Models of Lung Cancer06:51

Utilizing 18F-FDG PET/CT Imaging and Quantitative Histology to Measure Dynamic Changes in the Glucose Metabolism in Mouse Models of Lung Cancer

Published on: July 21, 2018

18.9K

Related Concept Videos

MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After...
24.7K
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
4.3K
The Ras Gene02:38

The Ras Gene

The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a...
7.5K
Small GTPases - Ras and Rho01:24

Small GTPases - Ras and Rho

Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
5.7K
MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
9.3K
lncRNA - Long Non-coding RNAs02:39

lncRNA - Long Non-coding RNAs

In humans, more than 80% of the genome gets transcribed. However, only around 2% of the genome codes for proteins. The remaining part produces non-coding RNAs which includes ribosomal RNAs, transfer RNAs, telomerase RNAs, and regulatory RNAs, among other types. A large number of regulatory non-coding RNAs have been classified into two groups depending upon their length – small non-coding RNAs, such as microRNA, which are less than 200 nucleotides in length, and long non-coding RNA...
10.2K