PTEN Loss in a Prostate Cancer Cohort From Jordan

Deletion of phosphatase and tensin homolog (PTEN) in prostate cancer has been associated with early biochemical recurrence, increased metastatic potential, and androgen independence. We evaluated the status of PTEN loss in a cohort of prostate cancer patients from Jordan. We investigated 71 patients with prostate cancer and 52 control subjects with benign prostatic hyperplasia (BPH). PTEN status was assessed by immunohistochemistry. PTEN mutations on exons 1, 2, 5, and 8 were also evaluated by polymerase chain reaction single-stranded conformation polymorphism (PCR-SSCP). We found PTEN loss in 42 of 71 (59.2%) evaluated prostate cancer cases by immunohistochemistry. In contrast, 51 of 52 BPH (98.1%) cases had an intact PTEN. In a subset of 24 prostate cancer cases evaluated by PCR-SSCP, we found PTEN mutations in 15 (62.5%) cases, whereas 22 (91.7%) of BPH controls lacked PTEN mutations. Exon 5 was the most frequently mutated exon (37.5%). Although the loss of PTEN was not significantly correlated with the Gleason Score (GS) or the World Health Organization (WHO)-International Society of Urological Pathology (ISUP) Grade Group (GG), we found higher frequency of PTEN loss (64%) in patients with GS >= 4+3/GG >= 3, compared with patients with GS <= 3+4/GG <= 2 (47.6%). In this first study to address the question of PTEN loss in a predominantly Arab population, we documented the frequency of PTEN loss in prostate cancer patients from Jordan, which was found to be higher than in comparable cohorts from East Asia, and was at the higher end of the range of reported frequency of PTEN loss in respective cohorts from North America and Western Europe. Although there was more frequent PTEN loss in cancers with higher GS/GG, this was not statistically significant.