miR-135a Reduces Osteosarcoma Pulmonary Metastasis by Targeting Both BMI1 and KLF4

Chenglong Chen1,2, Xingjia Mao3, Caitong Cheng3

  • 1Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, China.

Frontiers in Oncology
|April 8, 2021
PubMed

Insights

MicroRNA-135a (miR-135a) acts as a tumor suppressor in osteosarcoma (OS) by inhibiting cell invasion and metastasis. Targeting BMI1 and KLF4 with miR-135a offers a potential therapeutic strategy for OS treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Gene Regulation

Background:

  • Osteosarcoma (OS) treatment faces challenges due to modest response rates, leading to tumor recurrence and metastasis.
  • MicroRNA-135a (miR-135a) is known as an anticarcinogenic regulator in various cancers, but its role in OS is largely uncharacterized.

Purpose of the Study:

  • To investigate the expression and function of miR-135a in osteosarcoma.
  • To determine the relationship between miR-135a, BMI1, and KLF4 in OS.
  • To evaluate the therapeutic potential of miR-135a in OS.

Main Methods:

  • Assessed miR-135a expression in OS cells and tissues.
  • Performed ectopic expression of miR-135a in OS cells to analyze effects on invasion and oncogene expression.
  • Conducted *in vivo* xenograft studies in nude mice to evaluate tumor growth and metastasis inhibition.
  • Identified direct targets of miR-135a and compared its effects with targeting BMI1 and KLF4.

Main Results:

  • Abridged miR-135a expression was observed in OS cells and tissues, inversely correlated with oncogenes BMI1 and KLF4.
  • Ectopic miR-135a expression suppressed OS cell invasion and reduced BMI1/KLF4 levels.
  • *In vivo* studies confirmed miR-135a's tumor suppressor role, inhibiting tumor growth and lung metastasis.
  • BMI1 and KLF4 were identified as direct targets of miR-135a.

Conclusions:

  • miR-135a functions as a tumor suppressor in osteosarcoma.
  • Targeting the miR-135a/BMI1/KLF4 pathway presents a promising novel therapeutic strategy for osteosarcoma.