Background: Lumbar disc degeneration (LDD) is a ubiquitous finding in low back pain. Many different etiology factors may explain the LDD process, such as bone morphogenetic proteins (BMPs), DNA methylation, and gut microbiota. Until recently the mechanisms underlying the LDD process have been elusive.
View Article and Find Full Text PDFRepair of double strand breaks (DSBs) by RNA-binding proteins (RBPs) is vital for ensuring genome integrity. DSB repair is accompanied by local transcriptional repression in the vicinity of transcriptionally active genes, but the mechanism by which RBPs regulate transcriptional regulation is unclear. Here, we demonstrated that RBP hnRNPA2B1 functions as a RNA polymerase-associated factor that stabilizes the transcription complex under physiological conditions.
View Article and Find Full Text PDFSirtuin 6 (SIRT6), a member of the SIRT family, plays essential roles in the regulation of metabolism, inflammation, aging, DNA repair, and cancer development, making it a promising anticancer drug target. Herein, we present our use of proteolysis-targeting chimera (PROTAC) technology to formulate a series of highly potent and selective SIRT6 degraders. One of the degraders, , induced the near-complete degradation of SIRT6 in both SK-HEP-1 and Huh-7 cell lines and more potently inhibited hepatocellular carcinoma (HCC) cell proliferation than the parental inhibitors.
View Article and Find Full Text PDFBasal-like breast cancer may originate from luminal epithelial or cancerous cells. Inadequately repaired DNA damage impairs luminal differentiation and promotes aberrant luminal to basal trans-differentiation in mammary epithelial cells (MECs). Ubiquitin-specific peptidase 11 (USP11), a deubiquitinase, plays a critical role in DNA damage repair.
View Article and Find Full Text PDFCochlear hair cells (HCs) sense sound waves and allow us to hear. Loss of HCs will cause irreversible sensorineural hearing loss. It is well known that DNA damage repair plays a critical role in protecting cells in many organs.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2024
Breast Cancer Type 1 Susceptibility Protein (BRCA1) is a tumor-suppressor protein that regulates various cellular pathways, including those that are essential for preserving genome stability. One essential mechanism involves a BRCA1-A complex that is recruited to double-strand breaks (DSBs) by RAP80 before initiating DNA damage repair (DDR). How RAP80 itself is recruited to DNA damage sites, however, is unclear.
View Article and Find Full Text PDFThe fundamental role of cells in safeguarding the genome's integrity against DNA double-strand breaks (DSBs) is crucial for maintaining chromatin homeostasis and the overall genomic stability. Aberrant responses to DNA damage, known as DNA damage responses (DDRs), can result in genomic instability and contribute significantly to tumorigenesis. Unraveling the intricate mechanisms underlying DDRs following severe damage holds the key to identify therapeutic targets for cancer.
View Article and Find Full Text PDFGliomas are the most common malignant tumors of the central nervous system, accounting for approximately 80% of all malignant brain tumors. Accumulating evidence suggest that pyroptosis plays an essential role in the progression of cancer. Unfortunately, the effect of the pyroptosis-related factor caspase-4 (CASP4) on immunotherapy and drug therapy for tumors has not been comprehensively investigated.
View Article and Find Full Text PDFThe NAD-dependent deacetylase SIRT7 is a pivotal regulator of DNA damage response (DDR) and a promising drug target for developing cancer therapeutics. However, limited progress has been made in SIRT7 modulator discovery. Here, we applied peptide-based deacetylase platforms for SIRT7 enzymatic evaluation and successfully identified a potent SIRT7 inhibitor .
View Article and Find Full Text PDFMacroautophagy/autophagy is essential for the degradation and recycling of cytoplasmic materials. The initiation of this process is determined by phosphatidylinositol-3-kinase (PtdIns3K) complex, which is regulated by factor BECN1 (beclin 1). UFMylation is a novel ubiquitin-like modification that has been demonstrated to modulate several cellular activities.
View Article and Find Full Text PDFBackground: Inadequate DNA damage repair promotes aberrant differentiation of mammary epithelial cells. Mammary luminal cell fate is mainly determined by a few transcription factors including GATA3. We previously reported that GATA3 functions downstream of BRCA1 to suppress aberrant differentiation in breast cancer.
View Article and Find Full Text PDFR-loops are three-stranded structures that can pose threats to genome stability. RNase H1 precisely recognizes R-loops to drive their resolution within the genome, but the underlying mechanism is unclear. Here, we report that ARID1A recognizes R-loops with high affinity in an ATM-dependent manner.
View Article and Find Full Text PDFSix new compounds, including two depsidones garciculendepsidones A and B (1 and 2), one prenylated xanthone garciculenxanthone (3) and three dimeric xanthones bigarciculenxanthones A-C (4-6), were isolated from the twigs and leaves of Garcinia esculenta Y. H. Li.
View Article and Find Full Text PDFBidirectional signal transduction between tumor epithelial cells and tumor microenvironment (TME) is important for tumor development. Here we show that Lin28b/let-7 pathway is indispensable for modulating the expression of Wnt5a in tumor epithelium, which could be secreted and then up-regulates Lin28b in cancer-associated fibroblasts (CAFs). Moreover, we demonstrate that Lin28b in CAFs promoted growth of PDAC by inducing cytokine PCSK9's production.
View Article and Find Full Text PDFNat Struct Mol Biol
November 2023
Chromatin relaxation is a prerequisite for the DNA repair machinery to access double-strand breaks (DSBs). Local histones around the DSBs then undergo prompt changes in acetylation status, but how the large demands of acetyl-CoA are met is unclear. Here, we report that pyruvate dehydrogenase 1α (PDHE1α) catalyzes pyruvate metabolism to rapidly provide acetyl-CoA in response to DNA damage.
View Article and Find Full Text PDFAdding another constituent into a binary system, known as a ternary strategy, represents a simple and effective approach to boosting the power conversion efficiency (PCE) of organic solar cells (OSCs). Herein, we have prepared a new nonfused ring small-molecule acceptor with a medium bandgap, named DFTQA-2FIC, which possesses a high-lying lowest unoccupied molecular orbital energy level and a strong intramolecular charge-transfer effect. We elaborately utilized it as a third component in a typical PM6:Y6 blend to obtain high-performance ternary OSCs.
View Article and Find Full Text PDFTwo new guaiane-type sesquiterpenes, wenyujinolides A () and B (), were isolated from the ethanol extract of , together with 10 known compounds. Their structures were established by extensive spectroscopic methods (IR, ESIMS, HRESIMS, ECD, 1D and 2D NMR) and comparison of their NMR data with literatures. Compounds and were evaluated for the inhibition of NO production in LPS induced RAW 264.
View Article and Find Full Text PDFHistone deacetylase 6 (HDAC6) mediates DNA damage signaling by regulating the mismatch repair and nucleotide excision repair pathways. Whether HDAC6 also mediates DNA double-strand break (DSB) repair is unclear. Here, we report that HDAC6 negatively regulates DSB repair in an enzyme activity-independent manner.
View Article and Find Full Text PDFKeratin 17 (K17) is a cytoskeletal protein that is part of the intermediate filaments in epidermal keratinocytes. In K17 mice, ionizing radiation induced more severe hair follicle damage, whereas the epidermal inflammatory response was attenuated compared with that in wild-type mice. Both p53 and K17 have a major impact on global gene expression because over 70% of the differentially expressed genes in the skin of wild-type mice showed no expression change in p53 or K17 skin after ionizing radiation.
View Article and Find Full Text PDFBasal-like breast cancers (BLBCs) are among the most aggressive cancers, partly due to their enrichment of cancer stem cells (CSCs). Breast CSCs can be generated from luminal-type cancer cells via epithelial-mesenchymal transition (EMT). GATA3 maintains luminal cell fate, and its expression is lost or reduced in BLBCs.
View Article and Find Full Text PDFDNA damage repair (DDR) is a double-edged sword with different roles in cancer susceptibility and drug resistance. Recent studies suggest that DDR inhibitors affect immune surveillance. However, this phenomenon is poorly understood.
View Article and Find Full Text PDFThe histone deacetylase known as sirtuin 6 (SIRT6) deacetylates both histone and non-histone proteins but has low deacetylase activity in vitro. Here, we present a protocol to monitor SIRT6-mediated deacetylation of long-chain acyl-CoA synthase 5 in the presence of palmitic acid. We describe the purification of His-SIRT6 and a Flag-tagged substrate.
View Article and Find Full Text PDF