Editing SOX Genes by CRISPR-Cas: Current Insights and Future Perspectives

Evaluation of the paired-Cas9 nickase and RNA-guided FokI genome editing tools in precise integration of an anti-CD52 bicistronic monoclonal antibody expression construct at Chinese hamster ovary cells 18S rDNA locus

INTRODUCTION

The aim of this study was to compare two CRISPR/Cas9-based orthogonal strategies, paired-Cas9 nickase (paired-Cas9n) and RNA-guided FokI (RFN), in targeting 18S rDNA locus in Chinese hamster ovary (CHO) cells and precisely integrating a bicistronic anti-CD52 monoclonal antibody (mAb) expression cassette into this locus.

METHODS

T7E1 and high-resolution melt (HRM) assays were used to compare the ability of mentioned systems in inducing double-strand break (DSB) at the target site. Moreover, 5'- and 3'-junction polymerase chain reactions (PCR) were used to verify the accuracy of the targeted integration of the mAb expression cassette into the 18S rDNA locus. Finally, anti-CD52 mAb gene copy number was measured and, its expression was analyzed using ELISA and western blot assays.

RESULTS

Our results indicated that both paired-Cas9n and RFN induced DSB at the target site albeit RFN performance was slightly more efficient in HRM analysis. We also confirmed that the anti-CD52 mAb cassette was accurately integrated at the 18S rDNA locus and the mAb was expressed successfully in CHO cells.

CONCLUSION

Taken together, our findings elucidated that both paired-Cas9n and RFN genome editing tools are promising in targeting the 18S rDNA locus. Site specific integration of the bicistronic anti-CD52 mAb expression cassette at this locus in the CHO-K1 cells was obtained, using RFN. Moreover, proper expression of the anti-CD52 mAb at the 18S rDNA target site can be achieved using the bicistronic internal ribosome entry site (IRES)-based vector system.

Long non-coding RNA SOX2OT in tamoxifen-resistant breast cancer

Hormone receptor (HR)-positive breast cancer can become aggressive after developing hormone-treatment resistance. This study elucidated the role of long non-coding RNA (lncRNA) SOX2OT in tamoxifen-resistant (TAMR) breast cancer and its potential interplay with the tumor microenvironment (TME). TAMR breast cancer cell lines TAMR-V and TAMR-H were compared with the luminal type A cell line (MCF-7). LncRNA expression was assessed via next-generation sequencing, RNA extraction, lncRNA profiling, and quantitative RT-qPCR. SOX2OT overexpression effects on cell proliferation, migration, and invasion were evaluated using various assays. SOX2OT was consistently downregulated in TAMR cell lines and TAMR breast cancer tissue. Overexpression of SOX2OT in TAMR cells increased cell proliferation and cell invasion. However, SOX2OT overexpression did not significantly alter SOX2 levels, suggesting an independent interaction within TAMR cells. Kaplan-Meier plot analysis revealed an inverse relationship between SOX2OT expression and prognosis in luminal A and B breast cancers. Our findings highlight the potential role of SOX2OT in TAMR breast cancer progression. The downregulation of SOX2OT in TAMR breast cancer indicates its involvement in resistance mechanisms. Further studies should explore the intricate interactions between SOX2OT, SOX2, and TME in breast cancer subtypes.

SOX family transcription factors as therapeutic targets in wound healing: A comprehensive review

The SOX family plays a vital role in determining the fate of cells and has garnered attention in the fields of cancer research and regenerative medicine. It also shows promise in the study of wound healing, as it actively participates in the healing processes of various tissues such as skin, fractures, tendons, and the cornea. However, our understanding of the mechanisms behind the SOX family's involvement in wound healing is limited compared to its role in cancer. Gaining insight into its role, distribution, interaction with other factors, and modifications in traumatized tissues could provide valuable new knowledge about wound healing. Based on current research, SOX2, SOX7, and SOX9 are the most promising members of the SOX family for future interventions in wound healing. SOX2 and SOX9 promote the renewal of cells, while SOX7 enhances the microvascular environment. The SOX family holds significant potential for advancing wound healing research. This article provides a comprehensive review of the latest research advancements and therapeutic tools related to the SOX family in wound healing, as well as the potential benefits and challenges of targeting the SOX family for wound treatment.

gjSOX9 Cloning, Expression, and Comparison with gjSOXs Family Members in Gekko japonicus

SOX9 plays a crucial role in the male reproductive system, brain, and kidneys. In this study, we firstly analyzed the complete cDNA sequence and expression patterns for SOX9 from Gekko japonicus SOX9 (gjSOX9), carried out bioinformatic analyses of physiochemical properties, structure, and phylogenetic evolution, and compared these with other members of the gjSOX family. The results indicate that gjSOX9 cDNA comprises 1895 bp with a 1482 bp ORF encoding 494aa. gjSOX9 was not only expressed in various adult tissues but also exhibited a special spatiotemporal expression pattern in gonad tissues. gjSOX9 was predicted to be a hydrophilic nucleoprotein with a characteristic HMG-Box harboring a newly identified unique sequence, "YKYQPRRR", only present in SOXE members. Among the 20 SOX9 orthologs, gjSOX9 shares the closest genetic relationships with Eublepharis macularius SOX9, Sphacrodactylus townsendi SOX9, and Hemicordylus capensis SOX9. gjSOX9 and gjSOX10 possessed identical physicochemical properties and subcellular locations and were tightly clustered with gjSOX8 in the SOXE group. Sixteen gjSOX family members were divided into six groups: SOXB, C, D, E, F, and H with gjSOX8, 9, and 10 in SOXE among 150 SOX homologs. Collectively, the available data in this study not only facilitate a deep exploration of the functions and molecular regulation mechanisms of the gjSOX9 and gjSOX families in G. japonicus but also contribute to basic research regarding the origin and evolution of SOX9 homologs or even sex-determination mode in reptiles.