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MicroRNA Expression Profiles in Gastric Carcinogenesis.
Jinha Hwang1, Byung-Hoon Min2, Jiryeon Jang3,4
1Department of Biomedical Science, Seoul National University Graduate School, Seoul, Korea.
Scientific Reports
|September 28, 2018
Summary
MicroRNAs (miRNAs) are altered early in gastric cancer development, with some showing decreased expression from adenoma stages. These dysregulated miRNAs could serve as potential biomarkers for early gastric tumorigenesis.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Gastric carcinoma progresses through a multistep sequence involving genomic alterations.
- The role of microRNAs (miRNAs) in early gastric carcinogenesis remains incompletely understood.
Purpose of the Study:
- To identify differentially expressed miRNAs (DEMs) during the early stages of gastric carcinogenesis.
- To investigate the potential of miRNAs as biomarkers for early gastric cancer detection.
Main Methods:
- MicroRNA microarray profiling was conducted on 24 gastric tissue samples, including normal tissues, adenomas (low and high-grade dysplasia), and early gastric cancer (EGC).
- Expression patterns of 132 miRNAs were analyzed, with a focus on 42 aberrantly expressed miRNAs in EGC.
- Quantitative real-time PCR (RT-qPCR) was used to validate the expression of five representative miRNAs in an independent cohort of 77 samples.
Main Results:
- A total of 132 miRNAs showed altered expression across different stages of gastric tumorigenesis.
- Forty-two miRNAs were found to be aberrantly expressed in early gastric cancer (EGC).
- Specific miRNAs (e.g., miR-26a, miR-375) demonstrated decreased expression starting from the adenoma stage, while others (e.g., miR-200C, miR-29a) were downregulated in EGC compared to normal or adenoma tissues. Conversely, some miRNAs (e.g., miR-601, miR-107) showed increased expression in gastric cancer.
Conclusions:
- MicroRNA dysregulation occurs at the early stages of gastric tumorigenesis, indicating their involvement in the multistep carcinogenic process.
- The identified differentially expressed miRNAs represent potential candidate biomarkers for the early detection of gastric cancer.
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