CRISPR/Cas9-mediated deletion of a GA-repeat in human GPM6B leads to disruption of neural cell differentiation from NT2 cells

Modeling of cancer stem cells and the tumor microenvironment Via NT2/D1 cells to probe pathology and treatment for cancer and beyond

INTRODUCTION

Unique from the other tumor cells, tumorigenic cancer stem cells (CSCs) manifest as a subpopulation of cells within the tumor that exhibit genetic and phenotypic features and signaling processes, which escape traditional anti-oncogenic treatments, thereby triggering metastases and relapses of cancers. Critical to cancer biology is the crosstalk between CSCs and tumor microenvironment (TME), implicating a CSC-based cancer immunotherapy. Cognizant of CSCs' significant role in cancer pathology and treatment, finding a biological model that recapitulates CSCs and TME may allow a better understanding of tumor onset and progression for testing CSC-based therapies. In this review paper, we examined the CSC and TME characteristics of the human embryonal carcinoma NTERA-2 clonal cell line called NTERA-2 cl.D1 or NT2/D1 cells and discussed their potential utility for research and development of treatments for cancer and central nervous system (CNS) disorders.

METHODS

To probe our hypotheses that NT2/D1 cells display CSC and TME properties key to tumor development, which can serve as a screening platform to test cancer and CNS therapeutics, we conducted a literature review over a 10-year period (2014-2024), focusing on PUBMED and Science Direct published articles on cellular models of cancer, with emphasis on milestone research discoveries on NT2/D1 cells relevant to CSCs and TME. We categorized the studies under pre-clinical and clinical investigations in supporting the existence of CSC and TME features in NT2/D1 cells and providing a laboratory-to-clinic translational basis for cancer and CNS therapeutics.

CONCLUSIONS

NT2/D1 cells stand as a feasible biological model that recapitulates the crosstalk of CSCs and TME, which may critically contribute to our understanding of cancer and CNS biology and therapeutics. Designing therapeutics against CSCs' distinct self-renewal and differentiation capacities within the TME opens new avenues for treating cancers and CNS disorders.

Investigation of GPM6B as a novel therapeutic target in Osteoarthritis

BACKGROUND

Osteoarthritis (OA) is the most common motor system disease in older people, characterized by a high incidence and significant social and economic burden. Women have a higher risk of OA, more severe clinical symptoms, and a higher rate of disabilities than men. However, the pathogenesis of OA remains unclear. Therefore, we screened for differentially expressed genes (DEGs) in OA patients of different sex and searched for new targets that may be involved in regulating the development of OA.

METHODS

The study compared the expression of DEGs in synovial fluid exosomes between male and female patients with OA through RNA sequencing combined with bioinformatics analysis using public data. To evaluate the screened DEGs, synovial tissue and fluid samples were obtained from patients with OA who underwent joint replacement surgery. SiRNA-mediated knockdown in vitro experiments were performed to investigate the role of glycoprotein membrane 6B (GPM6B). Meanwhile, GPM6B gene knockout mice were used to assess the in vivo pathological roles of GPM6B in OA.

RESULTS

The results revealed that GPM6B is a potential target associated with OA. Immunofluorescence staining demonstrated that GPM6B was expressed in fibroblast-like synoviocytes (FLS) and macrophage-like synoviocytes in patients with OA. In vitro experiments confirmed that GPM6B knockdown can reduce the expression of inflammatory factors in primary FLS from patients with OA. Under inflammatory conditions, GPM6B knockdown can reduce the expression of matrix metalloproteinases as well as proliferation of FLS. In addition, using a destabilization of the medial meniscus-induced OA model, we revealed that GPM6B is associated with OA progression in mice.

CONCLUSION

Thus, we provided evidence that GPM6B act as a new target associated with OA.

A Hypermutable Region in the DISP2 Gene Links to Natural Selection and Late-Onset Neurocognitive Disorders in Humans

(CCG) short tandem repeats (STRs) are predominantly enriched in genic regions, mutation hotspots for C to T truncating substitutions, and involved in various neurological and neurodevelopmental disorders. However, intact blocks of this class of STRs are widely overlooked with respect to their link with natural selection. The human neuron-specific gene, DISP2 (dispatched RND transporter family member 2), contains a (CCG) repeat in its 5' untranslated region. Here, we sequenced this STR in a sample of 448 Iranian individuals, consisting of late-onset neurocognitive disorder (NCD) (N = 203) and controls (N = 245). We found that the region spanning the (CCG) repeat was highly mutated, resulting in several flanking (CCG) residues. However, an 8-repeat of the (CCG) repeat was predominantly abundant (frequency = 0.92) across the two groups. While the overall distribution of genotypes was not different between the two groups (p > 0.05), we detected four genotypes in the NCD group only (2% of the NCD genotypes, Mid-p = 0.02), consisting of extreme short alleles, 5- and 6-repeats, that were not detected in the control group. The patients harboring those genotypes received the diagnoses of probable Alzheimer's disease and vascular dementia. We also found six genotypes in the control group only (2.5% of the control genotypes, Mid-p = 0.01) that consisted of the 8-repeat and extreme long alleles, 9- and 10-repeats, of which the 10-repeat was not detected in the NCD group. The (CCG) repeat specifically expanded in primates. In conclusion, we report an indication of natural selection at a novel hypermutable region in the human genome and divergent alleles and genotypes in late-onset NhCDs and controls. These findings reinforce the hypothesis that a collection of rare alleles and genotypes in a number of genes may unambiguously contribute to the cognition impairment component of late-onset NCDs.

The human SMAD9 (GCC) repeat links to natural selection and late-onset neurocognitive disorders

INTRODUCTION

Whereas (GCC)-repeats are overrepresented in genic regions, and mutation hotspots, they are largely unexplored with regard to their link with natural selection. Across numerous primate species and tissues, SMAD9 (SMAD Family Member 9) reaches highest level of expression in the human brain. This gene contains a (GCC)-repeat in the interval between + 1 and + 60 of the transcription start site, which is in the high-ranking (GCC)-repeats with respect to length.

METHODS

Here we sequenced this (GCC)-repeat in 396 Iranian individuals, consisting of late-onset neurocognitive disorder (NCD) (N = 181) and controls (N = 215).

RESULTS

We detected two predominantly abundant alleles of 7 and 9 repeats, forming 96.2% of the allele pool. The (GCC)7/(GCC)9 ratio was in the reverse order in the NCD group versus controls (p = 0.005), resulting from excess of (GCC)7 in the NCD group (p = 0.003) and (GCC)9 in the controls (p = 0.01). Five genotypes, predominantly consisting of (GCC)7 and lacking (GCC)9 were detected in the NCD group only (p = 0.008). The patients harboring those genotypes received the diagnoses of Alzheimer's disease (AD) and vascular dementia (VD). Five genotypes consisting of (GCC)9 and lacking (GCC)7 were detected in the control group only (p = 0.002). The group-specific genotypes formed approximately 4% of the genotype pool in the human samples studied.

CONCLUSION

We propose natural selection and a novel locus for late-onset AD and VD at the SMAD9 (GCC)-repeat in humans.