Project description:Deoxynivalenol (DON) is one of the most common food contaminants, widely present in grain products. Studies using murine and porcine models show deoxynivalenol exposure impairs oocyte maturation and mitochondrial function; however, the exact mechanisms remain unclear. In the present study, we found DON exposure markedly altered the microtubule nucleation-associated proteins expression pattern of oocytes, while supplementation of Tubacin recovered the progress of oocyte maturation, as well as the expression of KIF11 and TPX2, which are key factors for microtubule nucleation and spindle stabilization. More importantly, with the in vivo TUBB8 oocyte-specific knock-in model which introduced the human β-tubulin isotype into the most widely used mouse model, we found inhibition of HDAC6 activity reconstructed morphologically normal spindles and drastically recovered polar-body extrusion rate by culturing with the specific HDAC6 inhibitor Tubacin in DON-exposed oocytes. Mechanistically, DON represses mRNA translation and disrupts ribosomal function. In our investigation, DON interfered with fertilized egg cleavage by disrupting microtubule and microfilament networks, and Tubacin enhanced microtubule acetylation, stabilizing the network and rescuing developmental arrest. Taken together, these findings elucidated the rescue effects of Tubacin on DON-induced reproductive toxicity in oocytes, and validated our TUBB8 oocyte-specific knock-in mouse model as a rapid evaluation of exposure and potential treatment of environmental pollutants to female reproductive health.
Project description:Microtubule-targeting agents have been widely used for cancer treatment, yet their cancer specificity is a common challenge. In this study, we identified that CMPD1 as a promising cancer specific inhibitor. Both in vitro and in vivo experiments showed that CMPD1 efficiently inhibits tumor growth. Mechanistically, CMPD1 inhibits microtubule polymerization in mitosis. Collectively, CMPD1 has the high potential to serve as a cancer cell inhibitor.
Project description:Endocrine therapy is the most important treatment modality of breast cancer patients whose tumors express the estrogen receptor (ER). The androgen receptor (AR) is also expressed in the vast majority (80-90%) of ER-positive tumors. However, AR-targeting drugs are not used in clinical practice, but have been evaluated in multiple trials and preclinical studies. We performed a genome-wide study to identify genetic context-dependent AR signaling induced by either AR agonist (dihydrotestosterone [DHT]), or AR antagonist (enzalutamide [Enz]), known as pharmacogenomic expression quantitative expression loci (PGx-eQTLs), utilizing a previously well characterized lymphoblastic cell line panel.
Project description:Parthenolide is a natural compound that has shown highly promising anticancer activity. Even though its mode of action has been studied for decades, its antimitotic activity has been largely overlooked, limiting the understanding of its full anticancer potential. In this study, we combined click chemistry with quantitative mass spectrometry and cell biology to elucidate the mechanism of action of parthenolide in mitosis. We show that parthenolide does not act as a microtubule-targeting agent in cells. Instead, it binds to the kinetochore protein ZNF207/BUGZ, preventing the establishment of proper kinetochore-microtubule attachment. Our results show that parthenolide covalently binds to Cys54 of BUGZ via Michael addition to its α-methylene-γ-lactone moiety. Since Cys54 is located within the second zinc finger domain of BUGZ microtubule-targeting region, we propose that parthenolide interferes with the microtubule-binding ability of BUGZ, consequently preventing kinetochore-microtubule attachments required for accurate chromosome congression to the spindle equator.
Project description:Search for SNPs associated with the pharmacogenomic profile of Benzidazole adverse reactions in Chagas Disease Homo sapiens patients.
Project description:This study is a comparative analysis to examine whether there are significant gene expression changes after 6 hours of treatment with three diverse microtubule destabilizers: combretastation A4 (CA4), vinblastine (VB), and plinabulin (PL). Other comparators include baseline control DMSO, microtubule destabilizer docetaxel (DTXL), and inflammatory cytokine TNF-α. We use primary human pulmonary microvascular endothelial cells as a model for a cell sensitive to microtubule perturbations.
Project description:Circular RNAs (circRNAs) are widely expressed in eukaryotes and highly regulated in a myriad of biological processes. While many studies indicate their activity as miRNA and protein sponges, little is known about their ability to directly control mRNA homeostasis. We show that a widely expressed circRNA, circZNF609, directly interacts with several mRNAs and increases their stability and/or translation by favouring the recruitment of the RNA-binding protein ELAVL1. Specifically, the interaction with Ckap5 mRNA, that interestingly overlaps the back-splicing junction, regulates microtubule homeostasis in several cancer cell lines and sustains cell-cycle progression. Finally, we show that circZNF609 downregulation increases the sensitivity to several microtubule-targeting cancer drugs in the regulation of microtubule metabolism and that LNA protectors against the Ckap5 pairing region on circZNF609 phenocopies such activity. These data set an example of how the small effects tuned by circZNF609/Ckap5 mRNA interaction might have potent output in tumour growth and drug response.
Project description:The transition of cancer cells between drug-sensitive and drug-tolerant persister phenotypes drives treatment failures. Using glioblastoma models, we identified MRK-740, an inhibitor of H3K4 methyltransferase PRDM7/9, as a potent enhancer of chemotherapy-induced cell death, resulting in elimination of glioblastoma persister cells. Mechanistic investigations as well as analysis of glioblastoma specimens revealed that H3K4me3 is a transcription-activating mark at the promoters of key genes involved in cholesterol biosynthesis. The inhibition of H3K4 methylation in cells treated with microtubule-targeting agents led to the disruption of cholesterol homeostasis and LXR-dependent cholesterol efflux, ultimately depleting intracellular cholesterol and causing the death of persisters. Furthermore, we have developed a brain permeable microtubule-targeting agent to validate these mechanistic findings in vivo. We show that a combination of our novel chemotherapeutic agent and a brain permeable LXR agonist significantly extends survival in a glioblastoma mouse model. These results uncover the importance of balanced cholesterol homeostasis in chemotherapy tolerance.