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miR-21 confers cisplatin resistance in gastric cancer cells by regulating PTEN

Shou-Mei Yang1, Cheng Huang, Xiao-Feng Li

  • 1School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei 230032, China.

Toxicology
|March 8, 2013
PubMed

Insights

MicroRNA-21 (miR-21) promotes cisplatin resistance in gastric cancer by downregulating PTEN and activating the Akt pathway. Inhibiting miR-21 can enhance chemotherapy effectiveness, offering a new therapeutic target.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Chemotherapy resistance is a significant challenge in cancer treatment.
  • MicroRNAs (miRNAs) play a role in drug resistance pathways.
  • The function of microRNA-21 (miR-21) in gastric cancer drug resistance is largely unknown.

Purpose of the Study:

  • To investigate the role of miR-21 in mediating resistance to cisplatin (DDP) in gastric cancer cells.
  • To explore the underlying molecular mechanisms of miR-21-induced chemoresistance.

Main Methods:

  • Comparison of miR-21 expression in cisplatin-sensitive (SGC7901) and resistant (SGC7901/DDP) gastric cancer cell lines.
  • Manipulation of miR-21 levels (overexpression and knockdown) to assess effects on cisplatin sensitivity.
  • Analysis of PTEN expression and Akt pathway activation.
  • Inhibition of the Akt pathway using LY 294002.

Main Results:

  • miR-21 expression was significantly upregulated in cisplatin-resistant gastric cancer cells.
  • Overexpression of miR-21 reduced cisplatin-induced apoptosis and proliferation inhibition.
  • Knockdown of miR-21 increased sensitivity to cisplatin.
  • miR-21 conferred resistance by downregulating PTEN and activating the Akt pathway.
  • Inhibition of Akt signaling abrogated miR-21-mediated cell survival.

Conclusions:

  • miR-21 plays a crucial role in conferring cisplatin resistance in gastric cancer.
  • The miR-21/PTEN/PI3K/Akt pathway is a key mechanism underlying chemoresistance.
  • Targeting miR-21 may represent a novel therapeutic strategy for overcoming cisplatin resistance in gastric cancer.

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