Evaluation of sperm DNA quality in men presenting with testicular cancer and lymphoma using alkaline and neutral Comet assays

Abstract

Despite more cancers in young men over the past two decades, improvements in therapies give a greater chance to live full lives following treatment. Sperm genomic quality is variable following cancer diagnosis, so its assessment is important if sperm cryopreservation is being considered. Here, we evaluated DNA damage using two DNA damage assays: an alkaline and for the first time, a neutral Comet assays in men presenting with testicular cancer (n = 19 for alkaline and 13 for neutral group) and lymphoma (n = 13 for alkaline and 09 for neutral group) compared with fertile donors (n = 20 for alkaline and 14 for neutral group). No significant differences were observed in any semen analysis parameters. In contrast, sperm DNA damage was higher in men with testicular cancer than in donors as assessed by both the alkaline (12.4% vs. 37.4%, p < 0.001) and neutral (7.5% vs. 13.4%; p < 0.05) Comet assays. Similar trends were observed in men with lymphoma. Here, sperm DNA damage was higher using both the alkaline (35.0% vs. 12.4%) and neutral (10.7% against 7.5% (p < 0.05) Comet assays. Moreover, the DNA strand breaks (particularly double-strand breaks) were significantly more prominent in men with cancer having abnormal seminal parameters than normozoospermic ones. This study showed that sperm DNA testing using alkaline and neutral Comet assays is more sensitive than semen analysis in detecting impaired sperm quality in men presenting with cancer. It may provide a useful adjunct when considering storage prior to cancer investigations and assisted reproductive techniques (ART)-based treatment.

Sperm DNA Fragmentation: A New Guideline for Clinicians

“…Genitourinary infections and subsequent leukocytospermia increases ROS production, increasing SDF [47][48][49][50][51]. Increase in SDF has also been reported in men with testicular cancer and other malignancies, which is suggested to be secondary to the associated endocrine alterations or OS in these pathologies [52][53][54][55].…”

Fatherhood and Sperm DNA Damage in Testicular Cancer Patients

“…The analysis is performed using a fluorescence microscope with imaging software. This test can be performed in both alkaline and neutral conditions: alkaline Comet reveals both SSBs and DSBs in sperm DNA, while neutral Comet is capable of selectively detect DSBs ( 104 ). The Comet assay has been used for both the in vitro evaluation of the mutagenic activity of various chemicals on sperm ( 105 ) and in preliminary studies of the correlation between fertility and basal sperm DNA damage ( 106 ).…”

“…The authors found impaired semen parameters (sperm concentration, normal forms, and motility), an elevated FSH serum concentration and elevated sperm DNA damage in the TC patients in comparison with the control group of healthy volunteers. More recently, Kumar et al detected increased sperm DNA damage in 19 testicular cancers patients vs. 20 semen donors with both alkaline and neutral COMET, with higher levels of sperm DNA fragmentation in TC patients with abnormal semen parameters ( 104 ). In particular, under neutral conditions, the Authors reported a significant difference in DNA DSBs in men presenting with testicular cancer compared to fertile donors.…”

Cryopreservation media differentially affect sperm motility, morphology and DNA integrity

“…However, researchers have not reached a firm consensus regarding the impact of cryopreservation on sperm DNA integrity (Di Santo et al ., ). The controversy in the literature could be due to differences in sample size, semen quality, cryopreservation method and tests used to evaluate DNA integrity (Isachenko et al ., ; Paasch et al ., ; Valcarce et al ., ,b; Kumar et al ., ).…”