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Let‑7d inhibits colorectal cancer cell proliferation through the CST1/p65 pathway

Jie Jiang1, Hui-Ling Liu1, Li Tao1

  • 1Department of Gastroenterology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, P.R. China.

International Journal of Oncology
|May 31, 2018
PubMed

Insights

MicroRNA let-7d inhibits colorectal cancer progression by downregulating Cystatin SN (CST1) via the CST1/p65 pathway. This finding suggests CST1 as a potential therapeutic target for colon cancer treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Cystatin SN (CST1) is a cysteine protease inhibitor and a known tumor biomarker for various carcinomas.
  • MicroRNAs (miRNAs) are crucial regulators of tumor cell proliferation, but the specific roles of let-7d and CST1 in colon cancer are not fully understood.

Purpose of the Study:

  • To investigate if let-7d inhibits colorectal carcinogenesis through the CST1/p65 pathway.
  • To determine the potential of let-7d and CST1 as clinical therapeutic targets for colorectal cancer.

Main Methods:

  • Microarray analysis of mRNA from colon cancer and normal tissues.
  • Reverse transcription-quantitative PCR (RT-qPCR), immunohistochemistry, and western blot analysis to confirm gene and protein expression.
  • Use of siRNA targeting CST1 (CST1-siRNA) and let-7d-mimics in HCT116 cells.

Main Results:

  • CST1 expression was significantly upregulated in colon cancer tissues and cell lines compared to normal tissues.
  • let-7d expression was downregulated in colon cancer patients and cell lines.
  • let-7d demonstrated an inhibitory effect on colorectal cancer cell proliferation by targeting the CST1/p65 pathway.

Conclusions:

  • let-7d inhibits colorectal carcinogenesis through the CST1/p65 pathway.
  • CST1 represents a potential therapeutic target for future clinical interventions in colorectal cancer treatment.

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