Potential role of hematopoietic pre-B-cell leukemia transcription factor-interacting protein in oral carcinogenesis.

Abstract

BACKGROUND:

Hematopoietic pre-B-cell leukemia transcription factor-interacting protein (HPIP) is a corepressor of pre-B-cell leukemia homeobox (PBX) 1 and is known to play a role in hematopoiesis. Recently, HPIP was demonstrated to promote breast cancer cell proliferation and hepatocellular carcinoma growth. Moreover, it has been revealed that homeobox and PBX proteins, the expression of which is regulated by HPIP, play key roles in cancer of various organs, including oral squamous cell carcinoma (OSCC). Nevertheless, there has not been any study regarding the role of HPIP in OSCC. This study investigated the expression of HPIP in normal oral mucosa, epithelial precursor lesion (OEPL), and OSCC, and the functional roles of HPIP in OSCC cells and normal keratinocytes.

MATERIALS AND METHODS:

Immunohistochemical analysis of HPIP, Ki-67, and involucrin was performed in OSCC specimens, and the change in involucrin expression following RNA interference treatment against HPIP was examined by quantitative RT-PCR and Western blot analysis in SCC9 and NHEK cells undergoing extracellular calcium-induced differentiation. Matrigel transwell and cell proliferation assays for both cell lines transfected with HPIP siRNA were also conducted.

RESULTS:

HPIP expression increased in OEPL and OSCC specimens. In vitro analysis revealed that HPIP suppressed differentiation and proliferation of SCC9 cells and transwell migration of NHEK cells, while HPIP promoted invasion of SCC9 and proliferation of NHEK cells. However, HPIP has no significant effect on NHEK cell differentiation.

CONCLUSION:

HPIP may play a critical role in oral carcinogenesis and is thus a potential target for anticancer therapy, with particular emphasis on its involvement in differentiation and migration/metastasis.

• Authors: Seiji Okada, Tarou Irié, Junichi Tanaka, Rika Yasuhara, Gou Yamamoto, Tomohide Isobe, Chie Hokazono, Tetsuhiko Tachikawa, Yohko Kohno, Kenji Mishima
• Journal: Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology (J Oral Pathol Med) Vol. 44 Issue 2 Pg. 115-25 (Feb 2015) ISSN: 1600-0714 [Electronic] Denmark
• PMID: 25060351 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Chemical References

• Co-Repressor Proteins
• Ki-67 Antigen
• PBXIP1 protein, human
• Protein Precursors
• RNA, Small Interfering
• Transcription Factors
• involucrin
• Calcium

Topics

• Adult
• Aged
• Calcium (pharmacology)
• Carcinogenesis (pathology)
• Carcinoma in Situ (pathology)
• Carcinoma, Squamous Cell (pathology)
• Cell Culture Techniques
• Cell Differentiation
• Cell Line, Tumor
• Cell Movement
• Cell Proliferation
• Co-Repressor Proteins
• Female
• Gene Silencing
• Humans
• Keratinocytes (pathology)
• Ki-67 Antigen (analysis)
• Male
• Middle Aged
• Mouth Mucosa (pathology)
• Mouth Neoplasms (pathology)
• Precancerous Conditions (pathology)
• Protein Precursors (analysis)
• RNA, Small Interfering (genetics)
• Transcription Factors (analysis, physiology)