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PI3K, Rac1 and pPAK1 are overexpressed in extramammary Paget's disease

Yue Qian1, Na Zhang, Siyuan Chen

  • 1Department of Dermatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Journal of Cutaneous Pathology
|August 1, 2012
PubMed
Abstract

Insights

Overexpression of PI3K, Rac1, and PAK1 was observed in extramammary Paget's disease (EMPD) tissues. These proteins may contribute to EMPD development and progression, particularly in invasive and metastatic cases.

Area of Science:

  • Oncology
  • Molecular Biology
  • Dermatopathology

Background:

  • The roles of Phosphatidylinositol 3-kinase (PI3K), Ras-related C3 botulinum toxin substrate 1 (Rac1), and P21-activated protein kinase 1 (PAK1) in tumor pathogenesis are recognized, but their involvement in extramammary Paget's disease (EMPD) remains unexplored.
  • Investigating these signaling molecules is crucial for understanding EMPD development.

Purpose of the Study:

  • To investigate the expression and potential role of PI3K, Rac1, and PAK1 in the pathogenesis of extramammary Paget's disease (EMPD).
  • To determine if these proteins are differentially expressed in various stages of EMPD, including non-invasive, invasive, and metastatic forms.

Main Methods:

  • Immunohistochemical staining was performed on 35 paraffin-embedded EMPD specimens.
  • Expression levels of PI3K (85α), Rac1, and phosphorylated PAK1 (pPAK1) were quantified in primary EMPD, metastatic lymph nodes, and normal apocrine glands.

Main Results:

  • Cytoplasmic overexpression of PI3K (85α), Rac1, and pPAK1 was detected in all 35 EMPD specimens.
  • Expression levels were significantly higher in EMPD compared to normal skin apocrine glands.
  • Elevated expression of these proteins correlated with invasive EMPD and lymph node metastasis, with significant positive correlations observed between PI3K (85α) and Rac1, and between Rac1 and pPAK1.

Conclusions:

  • PI3K, Rac1, and PAK1 are significantly overexpressed in EMPD.
  • These signaling molecules likely play a critical role in the pathogenesis and progression of EMPD.
  • Targeting these pathways may offer therapeutic strategies for EMPD.

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