ITGA6+ Human Testicular Cell Populations Acquire a Mesenchymal Rather than Germ Cell Transcriptional Signature during Long-Term Culture

Investigating SNHG3 as a potential therapeutic approach for HCC stem cells

INTRODUCTION

Hepatocellular Carcinoma (HCC) is a common malignant tumor worldwide. Long Non-Coding RNA (lncRNA) has gained attention in tumor biology, and this study aims to investigate the role of lncRNA SNHG3 in HCC, specifically in the self-renewal and maintenance of liver cancer stem cells.

METHODS

The expression of lncRNA SNHG3 was analyzed in HCC and adjacent normal tissue using the TCGA database. The expression levels of SNHG3 in HCC cell lines (Hep3B, HepG2, Huh7) were detected using qRT-PCR and Western blot techniques. Functional assays, including CCK-8, soft agar colony formation, and tumor sphere formation, were performed to evaluate the impact of SNHG3 on HCC stem cell functionality. MeRIP-qPCR was also used to investigate the regulatory role of SNHG3 in m6A modification of ITGA6 mRNA mediated by METTL3.

RESULTS

The study found that SNHG3 was significantly upregulated in HCC tissue and cell lines compared to normal liver tissue. SNHG3 expression correlated with the pathological stage, metastasis status, and tumor size of liver cancer. Inhibiting SNHG3 reduced proliferation, colony formation, and tumor sphere formation ability in HCC stem cells. SNHG3 also played a role in regulating the m6A modification and expression of ITGA6 through METTL3.

CONCLUSION

This study emphasizes the upregulation of lncRNA SNHG3 and its role in HCC stem cell self-renewal. SNHG3 may regulate the m6A modification of ITGA6 mRNA through its interaction with METTL3, impacting the function of liver cancer stem cells. These findings support the potential of targeting SNHG3 as a therapeutic approach for HCC.

Favorable culture conditions for spermatogonial propagation in human and non-human primate primary testicular cell cultures: a systematic review and meta-analysis

Introduction: Autologous transplantation of spermatogonial stem cells (SSCs) isolated from cryopreserved testicular biopsies obtained before oncological treatment could restore fertility in male childhood cancer survivors. There is a clear necessity for in vitro propagation of the limited SSCs from the testicular biopsy prior to transplantation due to limited numbers of spermatogonia in a cryopreserved testicular biopsy. Still, there is no consensus regarding their optimal culture method. Methods: We performed a systematic review and meta-analysis of studies reporting primary testicular cell cultures of human and non-human primate origin through use of Pubmed, EMBASE, and Web of Science core collection databases. Of 760 records, we included 42 articles for qualitative and quantitative analysis. To quantify in vitro spermatogonial propagation, spermatogonial colony doubling time (CDT) was calculated, which measures the increase in the number of spermatogonial colonies over time. A generalized linear mixed model analysis was used to assess the statistical effect of various culture conditions on CDT. Results: Our analysis indicates decreased CDTs, indicating faster spermatogonial propagation in cultures with a low culture temperature (32°C); with use of non-cellular matrices; use of StemPro-34 medium instead of DMEM; use of Knockout Serum Replacement; and when omitting additional growth factors in the culture medium. Discussion: The use of various methods and markers to detect the presence of spermatogonia within the reported cultures could result in detection bias, thereby potentially influencing comparability between studies. However, through use of CDT in the quantitative analysis this bias was reduced. Our results provide insight into critical culture conditions to further optimize human spermatogonial propagation in vitro, and effectively propagate and utilize these cells in a future fertility restoration therapy and restore hope of biological fatherhood for childhood cancer survivors.

Isolation and In Vitro Culture of Germ Cells and Sertoli Cells from Human Fetal Testis

In the human fetal testis, fetal germ cells (FGCs) are progressively surrounded by supporting Sertoli cells inside seminiferous cords. During the second trimester, the FGCs develop asynchronously and can be observed in several stages of development. However, the mechanism that regulates the transition between the different developmental stages as well as the formation of spermatogonia is currently not well understood. For this, it is necessary to develop suitable isolation protocols and a platform for in vitro culture of FGCs of different stages. Here, we report a method to isolate distinct populations of FGCs and Sertoli cells from second trimester human testis using a panel of conjugated antibodies for THY1, PDPN, ALPL, KIT, and SUSD2 for fluorescence-activated cell sorting (FACS) followed by in vitro culture up to 7 days. This platform provides the base for cellular and molecular characterization of the different testicular cell populations to investigate the transition between FGCs and spermatogonia and shed some light on crucial processes of early human gametogenesis unknown until now.

Spermatogonial Stem Cell-Based Therapies: Taking Preclinical Research to the Next Level

Fertility preservation via biobanking of testicular tissue retrieved from testicular biopsies is now generally recommended for boys who need to undergo gonadotoxic treatment prior to the onset of puberty, as a source of spermatogonial stem cells (SSCs). SSCs have the potential of forming spermatids and may be used for therapeutic fertility approaches later in life. Although in the past 30 years many milestones have been reached to work towards SSC-based fertility restoration therapies, including transplantation of SSCs, grafting of testicular tissue and various in vitro and ex vivo spermatogenesis approaches, unfortunately, all these fertility therapies are still in a preclinical phase and not yet available for patients who have become infertile because of their treatment during childhood. Therefore, it is now time to take the preclinical research towards SSC-based therapy to the next level to resolve major issues that impede clinical implementation. This review gives an outline of the state of the art of the effectiveness and safety of fertility preservation and SSC-based therapies and addresses the hurdles that need to be taken for optimal progression towards actual clinical implementation of safe and effective SSC-based fertility treatments in the near future.