Potential New Therapeutic Approaches for Cisplatin-Resistant Testicular Germ Cell Tumors.

BACKGROUND: Testicular germ cell tumors (TGCTs), a group of heterogeneous neoplasms, are the most frequent tumors of teenagers and young men, with the incidence rising worldwide. High cure rates can be achieved through cisplatin (CDDP)-based treatment, but approximately 10% of patients present refractory disease and virtually no treatment alternatives. Here, we explored new strategies to treat CDDP-resistant. METHODS: In vitro TGCT CDDP-resistance model was established and differential mRNA expression profiles were evaluated using NanoString technology. Then, TGCT cell lines were treated with four potential drugs (PCNA-I1, ML323, T2AA, and MG-132) to overcome CDDP-resistance. RESULTS: We found several differentially expressed genes related to DNA repair and cell cycle regulation on CDDP-resistant cell line (NTERA-2R) compared to parental cell line (NTERA-2P), and the proteasome inhibitor MG-132 demonstrated cytotoxic activity in all cell lines evaluated, even at a nanomolar range. MG-132 also enhanced cell lines' sensitivity to CDDP, increasing apoptosis in both NTERA-2P and NTERA-2R. CONCLUSIONS: MG-132 emerges as a potential new drug to treat CDDP-resistant TGCT. Targeted therapy based on molecular mechanism insights may contribute to overcome acquired chemotherapy CDDP-resistance.

Molecular Biology of Pediatric and Adult Male Germ Cell Tumors.

Cancer is a leading cause of death by disease in children and the second most prevalent of all causes in adults. Testicular germ cell tumors (TGCTs) make up 0.5% of pediatric malignancies, 14% of adolescent malignancies, and are the most common of malignancies in young adult men. Although the biology and clinical presentation of adult TGCTs share a significant overlap with those of the pediatric group, molecular evidence suggests that TGCTs in young children likely represent a distinct group compared to older adolescents and adults. The rarity of this cancer among pediatric ages is consistent with our current understanding, and few studies have analyzed and compared the molecular basis in childhood and adult cancers. Here, we review the major similarities and differences in cancer genetics, cytogenetics, epigenetics, and chemotherapy resistance between pediatric and adult TGCTs. Understanding the biological and molecular processes underlying TGCTs may help improve patient outcomes, and fuel further investigation and clinical research in childhood and adult TGCTs.