Thymosin Beta 15B (TMSb15B)

Thymosin beta15 is a small actin-binding protein upregulated in highly metastatic rat prostate cancer cells, relative to low metastatic cells. Thymosin beta15b, which is transcribed from an independent gene on human chromosome X.

The gene structure of thymosin beta15a and beta15b is conserved and the isoforms show 87% identity across the nucleotide sequence. Across the coding sequence the nucleotide differences are silent, resulting in identical proteins. Other thymosin family members have recently been shown to exert potent clinical effects. The functional data available for thymosin beta15, combined with the tumor expression pattern, suggest that thymosin beta15 may play an important role in tumor development and progression in addition to its value as a biomarker in prostate cancer.