The Incidence of Molecular/Genetic Markers in Testis Tissue From Severely and Mildly Oligospermic Men With Varicoceles and Infertility

Abstract

Genetic abnormalities in men with varicoceles may influence fertility and effect varicocelectomy outcome.In WBCs and sperm, these abnormalities occur more often in men with severe oligospermia (< 5 mil sperm/ml),but the overall incidence seems low(abnormal karyotype-5,6%,Y chromosome microdeletions-6.0%,CF mutations-1.2%,androgen receptor defects-1.1%,high sperm DNA damage-10.0%). In contrast,we studied molecular/genetic markers in testis tissue from infertile men with varicoceles. We present data on the incidence of testis markers in severely versus moderately oligospermic patients and report the influence on varicocelectomy outcome. A retrospective study on the incidence molecular/genetic markers in testis tissue that correlate with apoptosis,and their ability to predict varicocelectomy outcome. Percutanous testis aspiration biopsies with ultrasonic control were obtained at varicocelectomy (n = 119) or at sperm retrieval for ICSI in men with prior vasectomy and normal spermatogenesis (n = 5). Varicocele patients were divided into two groups (Group 1: <5 million/ml, n = 47; Group 2: > 5 million/ml, n = 72). Markers were examined by different techniques:[1] microscopy (BL thickness, germ cell count/tubule),[2] atomic absorption spectroscopy/autometallography (testicular Cd),[3] TUNEL (apoptosis),[4] RT-PCR (mRNAs for L-VDCC exons 6-9, CREMα and CREMτ), and[5] immunocytochemistry (L-VDCC, FasL, CD34, VEGF). Semen and marker data were available from 78 post varicocelectomy patients.A 50% increase in post op sperm density was considered sucessful, because men who achieved natural pregnancy after varicocelectomy demonstrated this level of increase. The median % apoptosis for varicocele patients was 17% versus controls 8.7% (p <0.05), and all markers were significantly correlated with apoptosis. The incidence of abnormal values among varicocele patients was: tissue Cd > 0.453 μg per mg dry weight (45/84 = 53.6%), L-VDCC microdeletions (24/44 = 54.5%), BL thickness > 7.1 microns (44/44 = 100%), absent HSP 701- (11/25 = 44.0%), absent CREMα (8/28 = 28.6%) and absent CREMτ (19/30 = 63.3%). There were no differences in the median values for the markers between the 2 groups (Mann-Whitney[MW] tests, p = 0.2 to 0.8, NS) or in the proportion of men with marker defects (Fisher exact[FE] tests, p = 0.2 to 1.0, NS). The median pre-op sperm density for Group 1 was 2.0 mil/ml(range: 1-2.75) versus 14.0 mil/ml(range: 10.0-18.0) for group 2 (p<0.001).The median post-op sperm density was 5.0 (range 2-11) versus 22 (range 17.25-30.0) respectively (p<0.001). The fraction increase was 0.667 for Group 1 and 0.36 for Group2 (p<0.008). In cases with high testis Cd or Ca Channel Microdeletions, the chances were 87.1% & 86.6%,respectively,that the post op change in sperm density would be <50%. Percutaneous testis aspiration biopsies with ultrasonic control are safe. The markers studied correlated with apoptosis and may control the final sperm density. The incidence of markers was > in testis than WBCs or sperm, but similar for severe and mild oligospermia. Testis markers may predict < 50% increase in sperm density after a varicocelectomy. When markers are absent, severely oligospermic men may show greatest % improvement. Markers may be used to explore specific medical therapies, or stratify patients in future prospective randomized trials.