Myt3 Mediates Laminin-V/Integrin-β1-Induced Islet-Cell Migration via Tgfbi

TGFBI: A novel therapeutic target for cancer

TGFBI, an extracellular matrix protein induced by transforming growth factor β, has been found to exhibit aberrant expression in various types of cancer. TGFBI plays a crucial role in tumor cell proliferation, angiogenesis, and apoptosis. It also facilitates invasion and metastasis in various types of cancer, including colon, head and neck squamous, renal, and prostate cancers. TGFBI, a prominent p-EMT marker, strongly correlates with lymph node metastasis. TGFBI demonstrates immunosuppressive effects within the tumor immune microenvironment. Targeted therapy directed at TGFBI shows promise as a potential strategy to combat cancer. Hence, a comprehensive review was conducted to examine the impact of TGFBI on various aspects of tumor biology, including cell proliferation, angiogenesis, invasion, metastasis, apoptosis, and the immune microenvironment. This review also delved into the underlying biochemical mechanisms to enhance our understanding of the research advancements related to TGFBI in the context of tumors.

ECM-based bioactive microencapsulation significantly improves islet function and graft performance

Microencapsulation is a promising strategy to prolong the survival and function of transplanted pancreatic islets for diabetes therapy, albeit its translation has been impeded by incoherent graft performance. The use of decellularized ECM has lately gained substantial research momentum due to its innate capacity to augment the function of cells originating from the same tissue type. In the present study, the advantages of both these approaches are leveraged in a porcine pancreatic ECM (pECM)-based microencapsulation platform, thus significantly enhancing murine pancreatic islet performance. pECM-encapsulated islets sustain high insulin secretion levels in vitro, surpassing those of islets encapsulated in conventional alginate microcapsules. Moreover, pECM-encapsulated islet cells proliferate and produce an enriched intra-islet ECM framework, displaying a distinctive structural rearrangement. The beneficial effect of pECM encapsulation is further reinforced by the temporary protection against cytokine-induced cytotoxicity. In-vivo, this platform significantly improves glucose tolerance and achieves glycemic correction in 100% of immunocompetent diabetic mice without any immunosuppression, compared to only 50% mice achieved glycemic correction by alginate encapsulation. Altogether, the results presented herein reveal that pECM-based microencapsulation offers a natural pancreatic niche that can restore the function of isolated pancreatic islets and deliver them safely, avoiding the need for immunosuppression. STATEMENT OF SIGNIFICANCE: Aiming to improve pancreatic islet transplantation outcomes in diabetic patients, we developed a microencapsulation platform based on pancreatic extracellular matrix (pECM). In these microcapsules the islets are entrapped within a pECM hydrogel that mimics the natural pancreatic microenvironment. We show that pECM encapsulation supports the islets' viability and function in culture, and provides temporal protection against cytokine-induced stress. In a diabetic mouse model, pECM encapsulation significantly improved glucose tolerance and achieved glycemic correction without any immunosuppression. These results reveal the potential of pECM encapsulation as a viable treatment for diabetes, providing a solid scientific basis for more advanced preclinical studies.

St18 specifies globus pallidus projection neuron identity in MGE lineage

The medial ganglionic eminence (MGE) produces both locally-projecting interneurons, which migrate long distances to structures such as the cortex as well as projection neurons that occupy subcortical nuclei. Little is known about what regulates the migratory behavior and axonal projections of these two broad classes of neurons. We find that St18 regulates the migration and morphology of MGE neurons in vitro. Further, genetic loss-of-function of St18 in mice reveals a reduction in projection neurons of the globus pallidus pars externa. St18 functions by influencing cell fate in MGE lineages as we observe a large expansion of nascent cortical interneurons at the expense of putative GPe neurons in St18 null embryos. Downstream of St18, we identified Cbx7, a component of Polycomb repressor complex 1, and find that it is essential for projection neuron-like migration but not morphology. Thus, we identify St18 as a key regulator of projection neuron vs. interneuron identity.

Screening key miRNAs and genes in prostate cancer by microarray analysis

BACKGROUND

Prostate cancer (PCa) is the second most frequent cancer and the fifth leading cause of cancer-related death in men while the mechanisms remain unclear.

METHODS

Differentially expressed mRNAs (DEmRNAs) and miRNAs (DEmiRNAs) between PCa and non-tumor controls were identified by using microarray analysis. Functional annotation of DEmRNAs, construction of protein-protein interaction (PPI) network and prediction of upstream transcription factors and downstream target DEmRNAs of DEmiRNAs were conducted to further research functions of key DEmRNAs and DEmiRNAs. Validation of selected DEmRNAs and survival analysis were conducted by using The Cancer Genome Atlas (TCGA).

RESULTS

Total of 91 DEmRNAs and 62 DEmiRNAs were obtained. Thrombospondin-4 precursor (THBS4) was the most significantly up-regulated DEmRNA whose product was predicted to interact with the hub protein of the PCa-specific PPI network, collagen type I alpha 1 chain (COL1A1). Both ATP binding cassette subfamily C member 4 (ABCC4) and endothelin receptor type B (EDNRB) have great prognostic value for PCa. Thrombospondin type 1 domain containing 4 (THSD4) was a down-regulated DEmRNA regulated by several cancer-related miRNAs including has-miR-107, hsa-miR-3175 and hsa-miR-484. Two miRNAs (hsa-miR-428 and hsa-miR-4284) involve in PCa by regulating BMP5-BAMBI interaction and TGF-beta signaling pathway. The expression of selected DEmRNAs between PCa and non-tumor controls in TCGA was consistent with that in our microarray analysis, generally.

CONCLUSIONS

Key DEmRNAs and DEmiRNAs between PCa and non-tumor controls were identified in this study which provided clues for exploring the molecular mechanism and developing potential biomarkers and therapeutic target sites for PCa.

Bufalin inhibits glycolysis-induced cell growth and proliferation through the suppression of Integrin β2/FAK signaling pathway in ovarian cancer

Bufalin is the major digoxin-like component of the traditional Chinese medicine Chansu and has obvious anti-tumor effect in major malignancies, but the role of bufalin in glucose metabolism in ovarian cancer remains illustrated. Here, we sought to elucidate the regulatory function of bufalin on cell glucose metabolism in ovarian cancer. The treatment of bufalin on ovarian cancer cells effectively inhibited glucose uptake and lactate production in ovarian cancer cells. The expression levels of glycolysis-related proteins, including GLUT4, LDHB and HK2, were decreased by the treatment of bufalin detected by qRT-PCR and immunoblotting. Mechanistically, bufalin exerted its anti-tumor effect by targeting ITGB2/FAK signaling pathway in vitro and in vivo, which could be rescued by the introduction of ITGB2 cDNA in ovarian cancer cells. These findings provide evidence that bufalin inhibited cellular glycolysis-induced cell growth and proliferation through repression of the ITGB2/FAK pathway, indicating that bufalin may be developed as a chemotherapeutic agent to treat ovarian cancer.

Bufalin enhances antitumor effect of paclitaxel on cervical tumorigenesis via inhibiting the integrin α2/β5/FAK signaling pathway

While Bufalin restrains primary tumorigenesis, the role of Bufalin in cervical cancer remains unclear. Here, we show that Bufalin can inhibit cervical cancer cell proliferation, block cell cycle in G2/M phase, induce cellular apoptosis and reduce cell metastasis through stimulation of p21^waf/cip1, p27^cip/kip, Bax and E-cadherin, and suppression of cyclin A, cyclin B1, CDK2, Bcl-2, Bcl-xl, MMP9 and SNAIL1. Further study suggests that Bufalin has no apparent damage to human normal cervical cells at the low concentration (<20nM), but increases the chemotherapeutic efficacy of paclitaxel. Mechanistic study reveals that Bufalin suppresses the integrin α2/FAK/AKT1/ GSK3β signaling. Finally, in vivo studies show that Bufalin blocks the Siha-induced xenograft tumor growth without detectable toxicity in the animals at the therapeutic doses, and the combination treatment of Bufalin and paclitaxel more efficiently inhibits xenograft tumor growth. Thus, Bufalin may be developed as a potential therapeutic agent to treat cervical cancer.

Myt3 suppression sensitizes islet cells to high glucose-induced cell death via Bim induction

Diabetes is a chronic disease that results from the body's inability to properly control circulating blood glucose levels. The loss of glucose homoeostasis can arise from a loss of β-cell mass because of immune-cell-mediated attack, as in type 1 diabetes, and/or from dysfunction of individual β-cells (in conjunction with target organ insulin resistance), as in type 2 diabetes. A better understanding of the transcriptional pathways regulating islet-cell survival is of great importance for the development of therapeutic strategies that target β-cells for diabetes. To this end, we previously identified the transcription factor Myt3 as a pro-survival factor in islets following acute suppression of Myt3 in vitro. To determine the effects of Myt3 suppression on islet-cell survival in vivo, we used an adenovirus to express an shRNA targeting Myt3 in syngeneic optimal and marginal mass islet transplants, and demonstrate that suppression of Myt3 impairs the function of marginal mass grafts. Analysis of grafts 5 weeks post-transplant revealed that grafts transduced with the shMyt3 adenovirus contained ~20% the number of transduced cells as grafts transduced with a control adenovirus. In fact, increased apoptosis and significant cell loss in the shMyt3-transduced grafts was evident after only 5 days, suggesting that Myt3 suppression sensitizes islet cells to stresses present in the early post-transplant period. Specifically, we find that Myt3 suppression sensitizes islet cells to high glucose-induced cell death via upregulation of the pro-apoptotic Bcl2 family member Bim. Taken together these data suggest that Myt3 may be an important link between glucotoxic and immune signalling pathways.