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Introduction: Testicular germ cell tumor is the most frequent neoplasia in men of reproductive age, with a 5‐year survival rate of 95%. Antineoplastic treatments induce sperm DNA fragmentation, especially within the first year post‐therapy. Data in the literature are heterogeneous concerning longer follow‐up periods, and the large majority is limited to 2 years. Objective: To define the timing for the recovery of sperm DNA damage and the proportion of patients with severe DNA damage at 2 and 3 years from the end of therapy. Materials and methods: Sperm DNA fragmentation was evaluated in 115 testicular germ cell tumor patients using terminal deoxynucleotidyl transferase dUTP nick end labeling assay coupled with flow cytometry before (T0) and 2 (T2) and 3 (T3) years post‐treatment. Patients were divided based on the type of treatment: carboplatin, bleomycin–etoposide–cisplatin, and radiotherapy. For 24 patients, paired sperm DNA fragmentation data were available at all time‐points (T0–T2–T3). Seventy‐nine cancer‐free, fertile normozoospermic men served as controls. Severe DNA damage was defined as the 95th percentile in controls (sperm DNA fragmentation = 50%). Results: Comparing patients versus controls, we observed: (i) no differences at T0 and T3 and (ii) significantly higher sperm DNA fragmentation levels (p < 0.05) at T2 in all treatment groups. Comparing pre‐ and post‐therapy in the 115 patients, the median sperm DNA fragmentation values were higher in all groups at T2, reaching significance (p < 0.05) only in the carboplatin group. While the median sperm DNA fragmentation values were also higher in the strictly paired cohort at T2, about 50% of patients returned to baseline. The proportion of severe DNA damage in the entire cohort was 23.4% and 4.8% of patients at T2 and T3, respectively. Discussion: Currently, testicular germ cell tumor patients are advised to wait 2 years post‐therapy before seeking natural pregnancy. Our results suggest that this period may not be sufficient for all patients. Conclusion: The analysis of sperm DNA fragmentation may represent a useful biomarker for pre‐conception counseling following cancer treatment. [ABSTRACT FROM AUTHOR]

Various signal transduction pathways seem to be involved in chemoresistance mechanism of glioblastomas (GBMs). miR-21 is an important oncogenic miRNA which modulates drug resistance of tumor cells. We analyzed the expression of 5 miRNAs, previously found to be dysregulated in high grade gliomas, in 9 pediatric (pGBM) and in 5 adult (aGBM) GBMs. miR-21 was over-expressed, with a significant difference between pGBMs and aGBMs represented by a 4 times lower degree of expression in the pediatric compared to the adult series (p = 0.001). Doxorubicin (Dox) seems to be an effective anti-glioma agent with high antitumor activity also against glioblastoma stem cells. We therefore evaluated the chemosensitivity to Dox in 3 GBM cell lines (A172, U87MG and T98G). Dox had a cytotoxic effect after 48 h of treatment in A172 and U87MG, while T98G cells were resistant. TUNEL assay verified that Dox induced apoptosis in A172 and U87MG but not in T98G. miR-21 showed a low basal expression in treated cells and was over-expressed in untreated cells. To validate the possible association of miR-21 with drug resistance of T98G cells, we transfected anti-miR-21 inhibitor into the cells. The expression level of miR-21 was significantly lower in T98G transfected cells (than in the parental control cells). Transfected cells showed a high apoptotic rate compared to control after Dox treatment by TUNEL assay, suggesting that combined Dox and miR-21 inhibitor therapy can sensitize GBM resistant cells to anthracyclines by enhancing apoptosis.