INPP4B exerts a dual function in the stemness of colorectal cancer stem-like cells through regulating Sox2 and Nanog...

Area of Science:

• Oncology
• Molecular Biology
• Cancer Stem Cell Research

Background:

• Inositol polyphosphate 4-phosphatase type II (INPP4B) is a lipid phosphatase implicated in cancer, but its function in colorectal cancer (CRC) and its stem-like cells (CR-CSLCs) is debated.
• The precise role and molecular mechanisms of INPP4B in CR-CSLCs remain largely unexplored.

Purpose of the Study:

• To investigate the expression, biological function, and molecular mechanism of INPP4B in human colorectal cancer stem-like cells (CR-CSLCs).
• To elucidate the role of INPP4B in regulating the stemness, self-renewal, chemoresistance, and tumorigenicity of CR-CSLCs.

Main Methods:

• Quantitative analysis of INPP4B expression in non-metastatic and highly metastatic CR-CSLCs.
• In vitro experiments involving INPP4B overexpression and knockdown in CR-CSLCs to assess self-renewal and chemoresistance.
• In vivo tumorigenicity assays in nude mice.
• Analysis of signaling pathways, including PI3K/PTEN/Akt, and stemness markers (Sox2, Nanog).

Main Results:

• INPP4B expression levels varied in CR-CSLCs, being decreased in non-metastatic and increased in highly metastatic subtypes.
• INPP4B demonstrated dual roles: inhibiting self-renewal and chemoresistance in non-metastatic CR-CSLCs, but promoting them in highly metastatic CR-CSLCs.
• INPP4B modulated CR-CSLC stemness by regulating Sox2 and Nanog expression via the PI3K/PTEN/Akt pathway, impacting tumorigenicity in vivo.

Conclusions:

• INPP4B plays a significant and context-dependent role in the stemness of CR-CSLCs.
• INPP4B acts as a dual therapeutic target in colorectal cancer, with potential for suppressing primary tumor growth and preventing metastasis.