Experimental cell research最新文献

Multiple myeloma (MM) is a malignant proliferative disorder of plasma cells and remains an incurable disease. Threonine and tyrosine kinase (TTK) is a dual-specific protein kinase that targets serine/threonine and tyrosine residues for phosphorylation. Its elevated expression has been linked to unfavorable outcomes in several types of cancer. Although the role of TTK in MM are still incompletely understood. In this research, we assessed TTK mRNA and protein expression levels in 51 MM patients and 30 healthy donors using qRT-PCR and western blotting. The impact of TTK expression on MM cell apoptosis, proliferation, and the cell cycle were assessed through CCK-8 assay, flow cytometry, and western blotting. Our findings revealed a significant overexpression of TTK in multiple myeloma patients and cell lines. TTK knockdown promoted apoptosis and G0/G1 phase arrest while inhibiting proliferation in MM cells, whereas TTK overexpression reduced apoptosis and G0/G1 phase arrest, enhancing proliferation in MM cells. Next, we identified regucalcin (RGN) as a downstream target of TTK through proteomic analysis. In NDMM, the expression of RGN was decreased. Cell function experiments showed that RGN knockdown significantly promoted MM cell proliferation, inhibited apoptosis and reduced cell cycle arrest, and reversed the increased apoptosis, weakened proliferation, and enhanced cell cycle arrest caused by TTK knockdown. Finally, a xenograft mouse model showed that TTK significantly promotes MM development. In summary, we demonstrated that the TTK-RGN axis regulates cell apoptosis, G0/G1 phase arrest, and proliferation in MM, highlighting TTK as a potential target for therapeutic intervention in this cancer.

Non-small cell lung cancer (NSCLC) is a subtype of the most frequently diagnosed cancer, causing a considerable number of deaths globally. Mitochondrial dysfunction was found to promote malignant progression. However, the underlying mechanism remains unclear. Acyl-CoA synthetase short chain family member 3 (ACSS3) is mainly located in mitochondria, which abnormal regulation is usually accompanied by the occurrence and development of tumors. In this study, we found that the expression level of ACSS3 was correlated with poor prognosis in patients with NSCLC. Moreover, we demonstrated that ACSS3 knockdown led to mitochondrial contraction, increased reactive oxygen species levels, decreased mitochondrial membrane potential, and subsequently inhibited tumor growth of NSCLC cells in vitro and in vivo, whereas its overexpression promoted these processes. Mechanistically, ACSS3 knockdown promoted ferroptosis through transcriptional control of SLC7A11 and GPX4. Further investigations indicated that ACSS3 loss inhibited the SLC7A11/GPX4 axis by enhancing p53 stability. Taken together, our data confirmed that ACSS3 promotes NSCLC tumorigenesis through inhibiting the p53-mediated ferroptosis. Hence, ACSS3 emerges as a promising therapeutic target for NSCLC treatment.

BRAF, a fundamental component of cellular signaling pathways regulating growth and survival, is frequently mutated in cancer development. Among entire BRAF mutations, the V600E substitution stands out as a dominant alteration in various malignancies, including melanoma, colorectal cancer, and thyroid cancer. Understanding the structural differences between wild-type BRAF and BRAFV600E is crucial for elucidating the molecular mechanisms underpinnings tumorigenesis and identifying dysregulation associated with the same. V600E mutation results in a constitutively active kinase domain, leading to dysregulated downstream signaling independent of extracellular stimuli. This sustained activation promotes cell proliferation, survival, angiogenesis, and hallmark features of the cancer cells. The study describes three distinct classes of BRAF mutations where Class 1 mutations predominantly involve point mutations within the BRAF gene, while Class 2 encompasses in-frame insertions and deletions, and Class 3 comprises gene fusions with large-scale chromosomal rearrangements. Further, we have discussed dysregulated pathways associated with mutation of BRAFV600E, which includes MAPK/ERK, PI3K/AKT/mTOR, TP53, DNA damage response, and WNT/β-Catenin from schematic representation. In the current review, we have shown how these dysregulated pathways play pivotal roles in tumorigenesis, tumor progression in BRAF-mutant cancers and highlighted the critical role of BRAF dysregulation in cancer development followed by its therapeutic implications of targeting dysregulated pathways in BRAF-driven malignancies.

Advancement of therapeutics for neurodegenerative diseases like amyotrophic lateral sclerosis (ALS) has been predominantly hampered by the dearth of relevant disease models. Despite numerous animal models, significant challenges remain in correlating these with human disease complexities. In this study, the ALS model was created using amniotic membrane-derived mesenchymal stem cells (AM-MSCs) which were differentiated into motor neurons (MN) with specific MN induction media and transiently transfected with mutated human SOD1 G93A plasmid to induce ALS-like condition. Characterization included gene expression analysis, immunocytochemistry, flow cytometry, and Western blot. Functional assays assessed the extent of degeneration and model efficiency. AM-MSCs demonstrated multipotency and were positive for MSC markers. Upon differentiation, the expression of MN markers like MNX1, Olig2, and ChAT were found to be elevated. SOD1 G93A overexpression, downregulated MN markers, upregulated NURR1 gene, reduced acetylcholine (ACh), reduced glutathione, and elevated oxidative stress markers. This robust in-vitro ALS model derived from AM-MSCs offers an alternative to animal models to provide an efficient and cost-effective platform to conduct rapid drug screening.

Background: As an evolutionarily conserved gene involved in embryonic development, cell differentiation, and immune metabolism, MYG1 exhibits a dynamic expression pattern related to development in human and mouse embryonic tissues, especially upregulates in undifferentiated or pluripotent stem cells. However, MYG1 has been poorly studied in breast cancer and its functional mechanism still remains unclear.

Method: Immunohistochemistry and immunofluorescence were used to study MYG1 expression and localization in breast cancer. Lentivirus transfection combined with CCK8, colony formation, matrix gel experiment and breast fat pad tumor formation in nude mice were used for in vivo and in vitro functional assessment. GSEA enrichment analysis, immunofluorescence and western blot were conducted to explore functional mechanism.

Result: MYG1 expression was upregulated in breast cancer and its higher expression correlated with a variety of clinicopathological characteristics indicating poor prognosis. In vitro and in vivo experiments showed that overexpression of MYG1 promoted breast cancer cells proliferation, migration, invasion and tumorigenesis, while downregulation of MYG1 had an opposite effect. Mechanistically, MYG1 interacted with HSP90 to significantly activate Wnt/β-catenin and Notch signaling pathways in breast cancer cells, thus promoting EMT, cell cycle process and breast cancer progression.

Conclusion: MYG1 is highly expressed in breast cancer and functions as an oncogene. Mechanistically, MYG1 interacts with HSP90 to accelerate EMT and cell cycle process by activating both Wnt/β-catenin and Notch signaling pathways.