Publications by authors named "Chang-xin Shi"

Here, we report an intermolecular carboacylation of terminal alkynes with tertiary and secondary alkyltrifluoroborates as well as acyl chlorides via photoredox/nickel dual catalysis, affording a varity of stereodefined trisubstituted enones in good to excellent yields and stereoselectivity, through a radical relay process. This redox-neutral protocol exhibits excellent functional group tolerance, exclusive regio- and stereoselectivity, and broad compatibility with various acyl chlorides and alkyltrifluoroborates.

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A novel photoredox/nickel dual catalytic intermolecular alkylarylation of vinylarenes with tertiary and secondary alkyltrifluoroborates and aryl bromides is described, which affords 1,1-diarylalkane frameworks that are found in various natural products as well as functionalized molecules in good to excellent yield and regioselectivity through a radical relay process. Notably, this redox-neutral reaction could proceed efficiently with good tolerance of various substrates, including a great diversity of commercially available (hetero)aryl bromides, alkyltrifluoroborates, and vinylarenes.

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Article Synopsis
  • Multiple myeloma (MM) is a type of cancer that affects plasma cells and often involves changes in a gene called MYC.
  • Research on special mice called Vk*MYC mice shows that when MYC is activated, it can lead to the growth of tumors, and these tumors can change over time with new mutations.
  • By studying these mice, scientists are learning about the different genetic changes in MM, which helps them understand how the disease develops and why it's still linked to the MYC gene, even as it gets more complicated.
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Unlabelled: Multiple myeloma (MM) is a malignancy that is often driven by MYC and that is sustained by IRF4, which are upregulated by super-enhancers. IKZF1 and IKZF3 bind to super-enhancers and can be degraded using immunomodulatory imide drugs (IMiD). Successful IMiD responses downregulate MYC and IRF4; however, this fails in IMiD-resistant cells.

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Despite advancements in profiling multiple myeloma (MM) and its precursor conditions, there is limited information on mechanisms underlying disease progression. Clincal efforts designed to deconvolute such mechanisms are challenged by the long lead time between monoclonal gammopathy and its transformation to MM. MM mouse models represent an opportunity to overcome this temporal limitation.

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Background: Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is a risk factor for cardiovascular disease. The relationship between CHIP and coronary microvascular dysfunction (CMD) is unknown. The current study examines the association between CHIP and CH with CMD and the potential relationships in risk for adverse cardiovascular outcomes.

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Identifying biomarkers associated with disease progression and drug resistance are important for personalized care. We investigated the expression of 121 curated genes, related to immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs) responsiveness. We analyzed 28 human multiple myeloma (MM) cell lines with known drug sensitivities and 130 primary MM patient samples collected at different disease stages, including newly diagnosed (ND), on therapy (OT), and relapsed and refractory (RR, collected within 12 months before the patients' death) timepoints.

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BCMA-CD3-targeting bispecific antibodies (BsAb) are a recently developed immunotherapy class which shows potent tumor killing activity in multiple myeloma (MM). Here, we investigated a murine BCMA-CD3-targeting BsAb in the immunocompetent Vk*MYC and its IMiD-sensitive derivative Vk*MYC models of MM. The BCMA-CD3 BsAb was safe and efficacious in a subset of mice, but failed in those with high-tumor burden, consistent with clinical reports of BsAb in leukemia.

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Human G-protein coupled receptor kinase 6 (GRK6) belongs to the GRK4 kinase subfamily of the G protein-coupled receptor kinase family which comprises of GRK1, GRK2, and GRK4. These kinases phosphorylate ligand-activated G-protein coupled receptors (GPCRs), driving heterotrimeric G protein coupling, desensitization of GPCR, and β-arrestin recruitment. This reaction series mediates cellular signal pathways for cell survival, proliferation, migration and chemotaxis.

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We generated eight multiple myeloma cell lines resistant to bortezomib; five acquired mutations. In 1,500 patients such mutations were rare clinically. To better understand disruption of proteasomes on multiple myeloma viability and drug sensitivity, we systematically deleted the major proteasome catalytic subunits.

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von Willebrand A domain-containing protein 8 (VWA8) is a poorly characterized, mitochondrial matrix-targeted protein with an AAA ATPase domain and ATPase activity that increases in livers of mice fed a high-fat diet. This study was undertaken to use CRISPR/Cas9 to delete VWA8 in cultured mouse hepatocytes and gain insight into its function. Unbiased omics techniques and bioinformatics were used to guide subsequent assays, including the assessment of oxidative stress and the determination of bioenergetic capacity.

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Article Synopsis
  • APY0201, a PIKfyve inhibitor, shows strong cellular cytotoxicity against multiple myeloma, confirmed through testing in 25 cell lines and 40% of 100 primary patient samples, especially in cases with trisomies and without t(11;14).
  • When compared to other PIKfyve inhibitors, APY0201 demonstrated superior potency, effectively reducing cell viability at very low concentrations in a majority of tested cell lines.
  • The treatment with APY0201 resulted in changes related to lysosomal function and autophagy, suggesting that its effectiveness in multiple myeloma may stem from disrupting these cellular processes, and establishing a predictive autophagy assay could help identify likely responsive patients.
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  • Researchers created human multiple myeloma cell lines (HMCLs) that are either sensitive or resistant to lenalidomide to study the mechanisms behind immunomodulatory drug (IMiD) resistance in multiple myeloma (MM).
  • Four HMCLs were resistant to all IMiDs tested but not to Bortezomib, with three showing abnormalities in the CRBN gene, while one (XG1LenRes) had high CD147 levels and active STAT3 signaling.
  • Inhibiting STAT3 re-sensitized XG1LenRes to lenalidomide, and targeting the IRF4/MYC pathway using a specific inhibitor restored lenalidomide sensitivity in this and other resistant HM
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About 15% of intrahepatic cholangiocarcinomas (ICCs) express constitutively active fibroblast growth factor receptor 2 (FGFR2) fusion proteins (FFs) generated by chromosomal translocations. FFs have been nominated as oncogenic drivers because administration of FGFR tyrosine kinase inhibitors (F-TKIs) can elicit meaningful objective clinical responses in patients carrying FF-positive ICC. Thus, optimization of FF targeting is a pressing clinical need.

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More effective treatment options for elderly acute myeloid leukemia (AML) patients are needed as only 25-50% of patients respond to standard-of-care therapies, response duration is typically short, and disease progression is inevitable even with some novel therapies and ongoing clinical trials. Anti-apoptotic BCL-2 family inhibitors, such as venetoclax, are promising therapies for AML. Nonetheless, resistance is emerging.

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Article Synopsis
  • Bortezomib is an effective treatment for multiple myeloma, but patients often develop resistance, prompting research to identify genetic factors that contribute to this issue.
  • Using CRISPR technology, researchers targeted over 19,000 human genes in myeloma cells to find those that may be linked to resistance against bortezomib.
  • Among the genes studied, PSMC6 was identified as a critical factor for bortezomib sensitivity; mutations in proteasome subunits could affect treatment efficacy, suggesting further investigation is needed in resistant patient populations.
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is one of the most recurrently mutated genes in multiple myeloma; however its role in disease pathogenesis has not been determined. Here we demonstrate that wild-type (WT) overexpression induces substantial cytotoxicity in multiple myeloma cells. In contrast, mutations found in multiple myeloma patients abrogate this cytotoxicity, indicating a survival advantage conferred by the mutant phenotype.

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The VWA8 gene was first identified by the Kazusa cDNA project and named KIAA0564. Based on the observation, by similarity, that the protein encoded by KIAA0564 contains a Von Willebrand Factor 8 domain, KIAA0564 was named Von Willebrand Domain-containing Protein 8 (VWA8). The function of VWA8 protein is almost unknown.

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Lenalidomide is an immunomodulatory drug (IMiDs) with clinical efficacy in multiple myeloma (MM) and other late B-cell neoplasms. Although cereblon () is an essential requirement for IMiD action, the complete molecular and biochemical mechanisms responsible for lenalidomide-mediated sensitivity or resistance remain unknown. Here, we report that IMiDs work primarily via inhibition of peroxidase-mediated intracellular HO decomposition in MM cells.

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Background: Immunomodulatory drugs (IMiDs), such as lenalidomide, are therapeutically active compounds that bind and modulate the E3 ubiquitin ligase substrate recruiter cereblon, thereby affect steady-state levels of cereblon and cereblon binding partners, such as ikaros and aiolos, and induce many cellular responses, including cytotoxicity to multiple myeloma (MM) cells. Nevertheless, it takes many days for MM cells to die after IMiD induced depletion of ikaros and aiolos and thus we searched for other cereblon binding partners that participate in IMiD cytotoxicity.

Methods: Cereblon binding partners were identified from a MM cell line expressing histidine-tagged cereblon by pulling down cereblon and its binding partners and verified by co-immunoprecipitation.

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Article Synopsis
  • The study looked at a protein called c-Maf, which is important in a type of cancer called multiple myeloma (MM) that affects plasma cells.
  • Researchers found that a protein named HERC4 connects with c-Maf and helps control its destruction in the body.
  • When HERC4 levels are low, as seen in MM, it can make the cancer grow faster, so targeting HERC4 could be a new way to treat MM.
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Human chromosomal region 13q14 is a deletion hotspot in prostate cancer, multiple myeloma, and chronic lymphocytic leukemia. This region is believed to host multiple tumor suppressors. Chromosome Condensation 1-like (CHC1L) is located at 13q14, and found within the smallest common region of loss of heterozygosity in prostate cancer.

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