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Approximately 31% of patients with 22q11.2 deletion syndrome (22q11.2DS) have genitourinary system disorders and 6% of them have undescended testes. Haploinsufficiency of genes on chromosome 22q11.2 might contribute to the risk of 22q11.2DS. In this study, we used mice with single-allele deletion in mitochondrial ribosomal protein L40 (Mrpl40+/−) as models to investigate the function of Mrpl40 in testes and spermatozoa development. The penetrance of cryptorchidism in Mrpl40+/− mice was found to be higher than that in wild-type (WT) counterparts. Although the weight of testes was not significantly different between the WT and Mrpl40+/− mice, the structure of seminiferous tubules and mitochondrial morphology was altered in the Mrpl40+/− mice. Moreover, the concentration and motility of spermatozoa were significantly decreased in the Mrpl40+/− mice. In addition, data-independent acquisition mass spectrometry indicated that the expression of genes associated with male infertility was altered in Mrpl40+/− testes. Our study demonstrated the important role of Mrpl40 in testicular structure and spermatozoa motility and count. These findings suggest that Mrpl40 is potentially a novel therapeutic target for cryptorchidism and decreased motility and count of spermatozoa.

Abstract Background Neuroblastoma (NB) is a common extracranial malignancy with high mortality in children. Recently, super-enhancers (SEs) have been reported to play a critical role in the tumorigenesis and development of NB via regulating a wide range of oncogenes Thus, the synthesis and identification of chemical inhibitors specifically targeting SEs are of great urgency for the clinical therapy of NB. This study aimed to characterize the activity of the SEs inhibitor GNE987, which targets BRD4, in NB. Results In this study, we found that nanomolar concentrations of GNE987 markedly diminished NB cell proliferation and survival via degrading BRD4. Meanwhile, GNE987 significantly induced NB cell apoptosis and cell cycle arrest. Consistent with in vitro results, GNE987 administration (0.25 mg/kg) markedly decreased the tumor size in the xenograft model, with less toxicity, and induced similar BRD4 protein degradation to that observed in vitro. Mechanically, GNE987 led to significant downregulation of hallmark genes associated with MYC and the global disruption of the SEs landscape in NB cells. Moreover, a novel candidate oncogenic transcript, FAM163A, was identified through analysis of the RNA-seq and ChIP-seq data. FAM163A is abnormally transcribed by SEs, playing an important role in NB occurrence and development. Conclusion GNE987 destroyed the abnormal transcriptional regulation of oncogenes in NB by downregulating BRD4, which could be a potential therapeutic candidate for NB.

Abstract Recent studies uncovered the emerging roles of SAPCD2 (suppressor anaphase-promoting complex domain containing 2) in several types of human cancer. However, the functions and underlying mechanisms of SAPCD2 in the progression of neuroblastoma (NB) remain elusive. Herein, through integrative analysis of public datasets and regulatory network of GSK-J4, a small-molecule drug with anti-NB activity, we identified SAPCD2 as an appealing target with a high connection to poor prognosis in NB. SAPCD2 promoted NB progression in vitro and in vivo. Mechanistically, SAPCD2 could directly bind to cytoplasmic E2F7 but not E2F1, alter the subcellular distribution of E2F7 and regulate E2F activity. Among the E2F family members, the roles of E2F7 in NB are poorly understood. We found that an increasing level of nuclear E2F7 was induced by SAPCD2 knockdown, thereby affecting the expression of genes involved in the cell cycle and chromosome instability. In addition, Selinexor (KTP-330), a clinically available inhibitor of exportin 1 (XPO1), could induce nuclear accumulation of E2F7 and suppress the growth of NB. Overall, our studies suggested a previously unrecognized role of SAPCD2 in the E2F signaling pathway and a potential therapeutic approach for NB, as well as clues for understanding the differences in subcellular distribution of E2F1 and E2F7 during their nucleocytoplasmic shuttling.