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Published on: July 21, 2018

KAI1/CD82 decreases Rac1 expression and cell proliferation through PI3K/Akt/mTOR pathway in H1299 lung carcinoma

Un-Jong Choi1, Bo-Keun Jee, Young Lim

  • 1Department of General Surgery, Wonkwang University School of Medicine, Iksan-City, Jeonbuk, Republic of Korea.

Cell Biochemistry and Function
|December 25, 2008
PubMed

Insights

The KAI1/CD82 protein reduces lung cancer metastasis by decreasing Rac1 expression via the PI3K/Akt/mTOR pathway, impacting cell growth and motility.

Area of Science:

  • Oncology
  • Cell Biology
  • Molecular Biology

Background:

  • The KAI1/CD82 protein is known to inhibit metastasis, but its precise mechanism remains unclear.
  • The acquisition of a motile phenotype is crucial for the initial stages of cancer metastasis.
  • Understanding KAI1/CD82's role in regulating cellular motility is key to developing anti-metastatic strategies.

Purpose of the Study:

  • To investigate the effects of KAI1/CD82 on the metastatic phenotype in H1299 lung carcinoma cells.
  • To elucidate the molecular mechanisms by which KAI1/CD82 influences cell metastasis.
  • To identify the signaling pathways involved in KAI1/CD82-mediated regulation of metastasis.

Main Methods:

  • Phase contrast microscopy was used to observe KAI1/CD82-induced morphological changes.
  • Rac1 expression and GTPase activity were measured to assess its regulation by KAI1/CD82.
  • The PI3K/Akt/mTOR signaling pathway was investigated to identify regulatory mechanisms.

Main Results:

  • KAI1/CD82 expression led to decreased Rac1 expression and GTPase activity without altering Rac1 mRNA levels.
  • KAI1/CD82 transfection resulted in lower mTOR expression and reduced cell growth in H1299 cells.
  • The PI3K/Akt/mTOR pathway was implicated in KAI1/CD82's regulation of Rac1.

Conclusions:

  • KAI1/CD82 decreases the metastatic phenotype in H1299 lung carcinoma cells.
  • The mechanism involves the down-regulation of Rac1 expression through the PI3K/Akt/mTOR signaling pathway.
  • KAI1/CD82 influences cell growth and motility by modulating Rac1 and mTOR signaling.

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