Detection of Recurrent Copy Number Loss at Yp11.2 Involving TSPY Gene Cluster in Prostate Cancer Using Array-Based Comparative Genomic Hybridization

University of Texas at San Antonio, San Antonio, Texas, United States
Cancer Research (Impact Factor: 9.33). 05/2006; 66(8):4055-64. DOI: 10.1158/0008-5472.CAN-05-3822
Source: PubMed


Prostate cancer is the second leading cause of cancer deaths among American men. The loss of Y chromosome has been frequently observed in primary prostate cancer as well as other types of cancer. Earlier, we showed that introduction of the human Y chromosome suppresses the in vivo tumorigenicity of the prostate cancer cell line PC-3. To further characterize the Y chromosome, we have developed a high-density bacterial artificial chromosome (BAC) microarray containing 178 BAC clones from the human Y chromosome. BAC microarray was used for array comparative genomic hybridization on prostate cancer samples and cell lines. The most prominent observation on prostate cancer specimens was a deletion at Yp11.2 containing the TSPY tandem gene array. Out of 36 primary prostate tumors analyzed, 16 (44.4%) samples exhibited loss of TSPY gene copies. Notably, we observed association between the number of TSPY copies in the blood and the incidence of prostate cancer. Moreover, PC-3 hybrids with an intact Yp11.2 did not grow tumors in nude mice, whereas PC-3 hybrids with a deletion at Yp11.2 grew tumors in nude mice.

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    • "Recent study of the different breeds of Bos taurus confirms gross variation in the copy number of this gene [51]. Significantly, an increase in copy number of tspy in humans is linked with male infertility [52], while a decrease is associated with prostate cancer [53]. The copy number of tspy ranges 20–60 in human males and 50–200 in bovid males [54], [55], which is consistent with our present study. "
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