Tumor Biology

, Volume 31, Issue 4, pp 359–361 | Cite as

Is Rab25 a tumor promoter or suppressor—context dependency on RCP status?

  • Bor Luen Tang
Research Commentary


Conflicting reports in the literature suggest that Rab25 could either be a context dependent promoter or suppressor of tumorigenesis. We hypothesized that whether Rab25 acts as a promoter or suppressor in tumor progression depends on the expression status of its effector, the Rab coupling protein (RCP). An elevated expression of RCP resulting from genomic amplification may enhance Rab25’s tumor progression activity. Elevation of Rab25 alone may sequester endogenous RCP, and attenuates its activating effect on other oncogenic products, such as mutant Ras.


Rab25 Rab coupling protein (RCP) Tumor promoter Tumor suppressor 



The author is grateful to the anonymous reviewers for their valuable suggestions, which improved the manuscript. He is supported by a grant from the Biomedical Research Council (BMRC) of the Agency for Science, Technology and Research (A*STAR) of Singapore (08/1/21/19/553), and declares no financial conflict of interest.


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Copyright information

© International Society of Oncology and BioMarkers (ISOBM) 2010

Authors and Affiliations

  1. 1.Department of Biochemistry, Yong Loo Lin School of Medicine, National University Health ServiceNational University of SingaporeSingaporeSingapore

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