Star-PAP regulates tumor protein D52 through modulating miR-449a/34a in breast cancer

Aizhu Duan1,2, Lingmei Kong1, Tao An1

  • 1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, P.R. China.

Biology Open
|October 26, 2019
PubMed

Insights

Star-PAP, a poly (A) polymerase, inhibits breast cancer progression by downregulating tumor protein D52 (TPD52) through microRNA-449a/34a (miR-449a/34a). This identifies Star-PAP as a potential therapeutic target for breast cancer.

Area of Science:

  • Molecular Biology
  • Oncology
  • Biochemistry

Background:

  • Tumor protein D52 (TPD52) is an oncogene implicated in various cancers.
  • MicroRNA-449a and microRNA-34a (miR-449a/34a) are tumor suppressors targeting TPD52 in breast cancer.
  • The upstream regulators of miR-449a/34a and TPD52 in breast cancer remain unclear.

Purpose of the Study:

  • To investigate the role of Star-papillary (Star-PAP) in regulating miR-449a/34a and TPD52 expression in breast cancer.
  • To elucidate the molecular mechanism by which Star-PAP influences breast cancer tumorigenesis.

Main Methods:

  • Correlation analysis of TPD52 and Star-PAP expression in breast cancer.
  • Overexpression and knockdown studies of Star-PAP.
  • RNA immunoprecipitation and pull-down assays to determine molecular interactions.
  • Rescue experiments involving TPD52 and miR-449a/34a modulation.

Main Results:

  • A negative correlation was observed between TPD52 and Star-PAP expression.
  • Star-PAP overexpression decreased TPD52 levels, while Star-PAP knockdown increased them.
  • Star-PAP directly binds to the 3' region of miR-449a, independent of TPD52.
  • Modulation of Star-PAP, miR-449a/34a, and TPD52 affected cell proliferation and apoptosis.

Conclusions:

  • Star-PAP acts as a tumor suppressor in breast cancer by negatively regulating TPD52 expression via miR-449a/34a.
  • This pathway represents a novel molecular mechanism in breast cancer development.
  • Star-PAP emerges as a potential therapeutic target for breast cancer treatment.

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