Changes in Expression of Specific mRNA Transcripts after Single- or Re-Irradiation in Mouse Testes

Alkylating agents and irradiation induce testicular damage, which results in prolonged azoospermia. Even very low doses of radiation can significantly impair testis function. However, re-irradiation is an effective strategy for locally targeted treatments and the pain response and has seen important advances in the field of radiation oncology. At present, little is known about the relationship between the harmful effects and accumulated dose of irradiation derived from continuous low-dose radiation exposure. In this study, we examined the levels of mRNA transcripts encoding markers of 13 markers of germ cell differentiation and 28 Sertoli cell-specific products in single- and re-irradiated mice. Our results demonstrated that re-irradiation induced significantly decreased testicular weights with a significant decrease in germ cell differentiation mRNA species (Spo11, Tnp1, Gfra1, Oct4, Sycp3, Ddx4, Boll, Crem, Prm1, and Acrosin). In the 13 Sertoli cell-specific mRNA species decreased upon irradiation, six mRNA species (Claudin-11,Espn, Fshr, GATA1, Inhbb, and Wt1) showed significant differences between single- and re-irradiation. At the same time, different decreases in Sertoli cell-specific mRNA species were found in single-irradiation (Aqp8, Clu, Cst12, and Wnt5a) and re-irradiation (Tjp1, occludin,ZO-1, and ZO-2) mice. These results indicate that long-term aspermatogenesis may differ after single- and re-irradiated treatment.

Changes in Expression of Specific mRNA Transcripts after Single- or Re-Irradiation in Mouse Testes

Alkylating agents and irradiation induce testicular damage, which results in prolonged azoospermia. Even very low doses of radiation can significantly impair testis function. However, re-irradiation is an effective strategy for locally targeted treatments and the pain response and has seen important advances in the field of radiation oncology. At present, little is known about the relationship between the harmful effects and accumulated dose of irradiation derived from continuous low-dose radiation exposure. In this study, we examined the levels of mRNA transcripts encoding markers of 13 markers of germ cell differentiation and 28 Sertoli cell-specific products in single- and re-irradiated mice. Our results demonstrated that re-irradiation induced significantly decreased testicular weights with a significant decrease in germ cell differentiation mRNA species (Spo11, Tnp1, Gfra1, Oct4, Sycp3, Ddx4, Boll, Crem, Prm1, and Acrosin). In the 13 Sertoli cell-specific mRNA species decreased upon irradiation, six mRNA species (Claudin-11, Espn, Fshr, GATA1, Inhbb, and Wt1) showed significant differences between single- and re-irradiation. At the same time, different decreases in Sertoli cell-specific mRNA species were found in single-irradiation (Aqp8, Clu, Cst12, and Wnt5a) and re-irradiation (Tjp1, occludin, ZO-1, and ZO-2) mice. These results indicate that long-term aspermatogenesis may differ after single- and re-irradiated treatment.

Transcriptome analysis reveals upregulation of immune response pathways at the invasive tumour front of metastatic seminoma germ cell tumours

Background Testicular germ cell tumours (TGCTs) have a high metastasis rate. However, the mechanisms related to their invasion, progression and metastasis are unclear. Therefore, we investigated gene expression changes that might be linked to metastasis in seminomatous testicular germ cell tumour (STGCT) patients. Methods Defined areas [invasive tumour front (TF) and tumour centre (TC)] of non-metastatic (with surveillance and recurrence-free follow-up >2 years) and metastatic STGCTs were collected separately using laser capture microdissection. The expression of 760 genes related to tumour progression and metastasis was analysed using nCounter technology and validated with quantitative real-time PCR and enzyme-linked immunosorbent assay. Results Distinct gene expression patterns were observed in metastatic and non-metastatic seminomas with respect to both the TF and TC. Comprehensive pathway analysis showed enrichment of genes related to tumour functions such as inflammation, angiogenesis and metabolism at the TF compared to the TC. Remarkably, prominent inflammatory and cancer-related pathways, such as interleukin-6 (IL-6) signalling, integrin signalling and nuclear factor-κB signalling, were significantly upregulated in the TF of metastatic vs non-metastatic tumours. Conclusions IL-6 signalling was the most significantly upregulated pathway in metastatic vs non-metastatic tumours and therefore could constitute a therapeutic target for future personalised therapy. In addition, this is the first study showing intra- and inter-tumour heterogeneity in STGCT.

Depression, anxiety and health-related quality of life in paediatric intracranial germ cell tumor survivors

Background Little is known about depression and anxiety among paediatric intracranial germ cell tumour (iGCT) survivors. We aimed to evaluate the risk factors associated with depression, anxiety and health-related quality of life (HRQoL) in paediatric iGCT survivors. Methods We recruited 200 iGCT patients (and their parents) from Beijing Tiantan Hospital and assessed their HRQoL using the Paediatric Quality of Life Inventory (PedsQL) 4.0 Generic Core Scales. The Children’s Depression Inventory, Screen for Child Anxiety Related Emotional Disorders, and Symptom Checklist 90 were used to evaluate depression and anxiety. The results were analysed based on disease recurrence, tumour location and treatment strategies. Results Survivors with recurrent tumours had worse HRQoL scores than those with non-recurrent tumours. Patients with tumours involving both the suprasellar and basal ganglia regions had the worst HRQoL scores. A large proportion of survivors had depression or anxiety. Both depression and anxiety scores were highly correlated with the HRQoL emotional functioning scores. The parent proxy-reports (PPR) and child self-reports were highly correlated in all domains. Conclusions This study demonstrated the clinical factors affecting paediatric iGCT survivors’ depression, anxiety, and HRQoL. Therefore, psychological interventions should be implemented. It also suggests that the PedsQL PPR would be helpful for routine screening.

TEX13B is important for germ cell development and male fertility

The recent epidemiological studies suggest that nearly one out of every 7 reproductive age couples face problem to conceive a child after trying for at least one year. Impaired fertility of the male partner is causative in approximately 50% of the infertile couples. However, the etiologies of large proportion of male infertility are still unclear. Our unpublished exome sequencing data identified several novel genes including TEX13B, which motivated us to further explore the role of TEX13B in male infertility in large infertile case control cohort. Hence in this study, we have examined the role of TEX13B in male infertility by whole gene sequencing 628 infertile and 427 control men and have demonstrated the functional role of Tex13b in spermatogonia GC1spg (GC1) cells. We identified 2 variants on TEX13B which are tightly associated with male infertility. TEX13B gene exclusively expressed in germ cells, but its molecular functions in germ cells are still unknown. Hence, we demonstrated the functional importance of Tex13b in GC1 cell line by genomic manipulation via CRISPR-Cas9 and mass spectrometry-based whole cell proteomics. The gene knock out in GC1 cell line clearly shows that Tex13b play an important role in germ cell growth and morphology. We demonstrate that Tex13b knockout or conditional overexpression in GC1 cells reprograms the metabolic status from an oxidative phosphorylation to glycolysis state and vice versa. In conclusion, our study clearly showed the importance of Tex13b in germ cells development and Its association with male infertility.

Mouse CHD4-NURD is Required for Neonatal Spermatogonia Survival and Normal Gonad Development.

Testis development and sustained germ cell production in adults rely on the establishment and maintenance of spermatogonia stem cells and their proper differentiation into spermatocytes. Chromatin remodeling complexes regulate critical processes during gamete development by restricting or promoting accessibility of DNA repair and gene expression machineries to the chromatin. Here, we investigated the role of CHD4 and CHD3 catalytic subunits of the NURD complex during spermatogenesis. Germ cell-specific deletion of Chd4 early in gametogenesis, but not Chd3, resulted in arrested early gamete development due to failed cell survival of neonate undifferentiated spermatogonia stem cell population. Candidate assessment revealed that CHD4 controls expression of Dmrt1 and its downstream target Plzf, both described as prominent regulators of spermatogonia stem cell maintenance. Our results show the requirement of CHD4 in mammalian gametogenesis pointing to functions in gene expression early in the process.