Cardiac fibrosis and remodeling are critical contributors to heart failure, particularly in the context of diabetes, where hyperglycemia (HG) exacerbates pathological fibroblast activity. Despite the known cardiovascular...Cardiac fibrosis and remodeling are critical contributors to heart failure, particularly in the context of diabetes, where hyperglycemia (HG) exacerbates pathological fibroblast activity. Despite the known cardiovascular benefits of canagliflozin (CANA), its specific effects on human cardiac fibroblasts (HCFs) under HG conditions remain unexplored. We investigated whether CANA could mitigate HG-induced detrimental responses in HCFs. Dose-response assays revealed that 100 nM CANA significantly reduced HG-induced proliferation and migration of HCFs. Furthermore, CANA attenuated mitochondrial reactive oxygen species (ROS) production, a key driver of myofibroblast differentiation, and suppressed HG-induced expression of SMAD2, a critical activator of cardiac fibroblasts. Additionally, HG disrupted calcium (Ca) homeostasis, which was ameliorated by CANA treatment. These findings collectively demonstrate that CANA exerts protective effects on HCFs by improving mitochondrial function, restoring Ca handling, and reducing fibroblast proliferation, migration, and activation under HG conditions.
Cells regulate the expression of cell cycle-related genes, including cyclins essential for mitosis, through the transcriptional activity of the positive transcription elongation factor b (P-TEFb), a complex comprising CD...Cells regulate the expression of cell cycle-related genes, including cyclins essential for mitosis, through the transcriptional activity of the positive transcription elongation factor b (P-TEFb), a complex comprising CDK9, cyclin T, and transcription factors. P-TEFb cooperates with CDK7 to activate RNA polymerase. In response to DNA stress, the cell cycle shifts from mitosis to repair, triggering cell cycle arrest and the activation of DNA repair genes. This tight coordination between transcription, cell cycle progression, and DNA stress response is crucial for maintaining cellular integrity. Cyclin-dependent kinases CDK7 and CDK9 are central to both transcription and cell cycle regulation. CDK7 functions as the CDK-activating kinase (CAK), essential for activating other CDKs, while CDK9 acts as a critical integrator of signals from both the cell cycle and transcriptional machinery. This review elucidates the mechanisms by which CDK7 and CDK9 regulate the mitotic process and cell cycle checkpoints, emphasizing their roles in balancing cell growth, homeostasis, and DNA repair through transcriptional control.
α-Fodrin, a known scaffolding protein for cytoskeleton stabilization, performs various functions including cell adhesion, cell motility, DNA repair and apoptosis. Based on our previous results revealing its role in mitos...α-Fodrin, a known scaffolding protein for cytoskeleton stabilization, performs various functions including cell adhesion, cell motility, DNA repair and apoptosis. Based on our previous results revealing its role in mitosis in glioblastoma, we have examined its effect in pancreatic cancer, which is often linked to mitotic aberrations including aneuploidy and chromosome instability. Here, we show that the expression of α-Fodrin increases in pancreatic adenocarcinoma tissues compared to its normal counterpart, suggesting its tumor promoting role. shRNA-mediated knock-down of α-Fodrin significantly reduces the xenograft growth in immunocompromised mice underscoring the importance of α-Fodrin in tumor progression. CENP-E (centromere-associated protein E) is a motor protein essential for chromosomal alignment and segregation during mitosis. We have found that α-Fodrin interacts with CENP-E to recruit it to the kinetochore and depletion of α-Fodrin has a crucial role in controlling aneuploidy. As these mitotic defects can lead to apoptosis, we have further evaluated the activation of possible upstream pathways. Paclitaxel, a chemotherapeutic agent that stabilizes microtubules, disrupts mitosis and induces apoptosis. We found that Paclitaxel triggered stronger activation of JNK, ERK, and P38 MAPKs, altered BCL2/BAX ratios, cytochrome C release causing increased apoptosis in α-Fodrin knockdown cells compared to cells with wild-type α-Fodrin. This enhanced sensitivity to paclitaxel is consistent with improved survival in pancreatic cancer patients with low α-Fodrin () and low CENP-E expression compared to poor prognosis with high expressions of both the genes. Taken together, this study provides the molecular mechanism by which α-Fodrin - CENP-E axis regulates pancreatic cancer progression and drug response.
While the Warburg effect is well-known and frequently studied, the molecular features that facilitate increased tumor cell glycolytic activity have yet to be extensively investigated. We hypothesized that amplification o...While the Warburg effect is well-known and frequently studied, the molecular features that facilitate increased tumor cell glycolytic activity have yet to be extensively investigated. We hypothesized that amplification of genes encoding proteins related to glucose metabolism could be a mechanism to facilitate increased glycolysis. Thus, we applied a precision-guided copy number variation analysis approach to the GLP1R, AMFR, GCG, GPI, and ACTA1 genes across three different cancer types. Results indicated that higher CNs of GLP1R in glioblastoma were associated with better patient outcomes, while high CNs of GPI in lower-grade gliomas were associated with worse outcomes. Results also indicated that high microsatellite instability directly correlated with high CNs for most of the above indicated genes. These approaches to assessing tumor metabolism-related genes may lead to more accurate measures of patient risk and potential additional treatment options.
Posttranslational modification of proteins plays a fundamental role in cell biology. It provides cells a means to regulate the signaling, enzymatic or structural properties of proteins without continuous cycles of synthe...Posttranslational modification of proteins plays a fundamental role in cell biology. It provides cells a means to regulate the signaling, enzymatic or structural properties of proteins without continuous cycles of synthesis and degradation, offering multiple distinct functions to individual proteins in a rapid and reversible manner. Modifications can include phosphorylation, ubiquitination or methylation, which are widespread and simple to detect using current approaches. More challenging to identify, one modification of growing significance is the direct oxidation of cysteine and methionine side chains. Protein oxidation has long been known to occur spontaneously upon the accumulation of cellular reactive oxygen species (ROS), but new data are providing insight into the targeted oxidation of proteins by flavin-containing monooxygenases (FMOs). Here, we review how oxidation of cellular proteins can modulate their activity and consider potential roles for FMOs in the targeted modification of proteins shaping cell division, with a particular focus on two families of FMOs: MICAL and OSGIN.
Exosomes secreted by mesenchymal stem cells (MSCs) have been considered as a novel biological therapy for myocardial ischemia/reperfusion injury (MIRI). However, the underlying mechanism of exosomes has not been complete...Exosomes secreted by mesenchymal stem cells (MSCs) have been considered as a novel biological therapy for myocardial ischemia/reperfusion injury (MIRI). However, the underlying mechanism of exosomes has not been completely established, especially in the early stage of MIRI. In this study, we primarily investigated the protective effect of exosomes on MIRI from both in vitro and ex vivo perspectives. Bioinformatic analysis was conducted to identify exosomal miRNA associated with myocardial protection, Genes and proteins related to functional studies and myocardial energy metabolism were analyzed and evaluated using techniques such as Polymerase Chain Re-action (PCR), Western blotting, double luciferase biochemical techniques, flow cytometry assay, etc. It was discovered that exosomes ameliorated cardiomyocyte injury t by delivery of miR-132-3p.This process reduced the expression of Phosphatase and tensin homolog (PTEN) mRNA and protein, enhanced the expression of phosphorylated protein kinase (pAKT), regulated the insulin signaling pathway, facilitated intracellular Glucose transporter 4 (GLUT4) protein membrane translocation, and enhanced glucose uptake and Adenosine Triphosphate (ATP) production. This study confirmed, for the first time, that MSC-EXO can provide myocardial protection in the early stages of MIRI through miR-132/PTEN/AKT pathway. This research establishes a theoretical and experimental foundation for the clinical application of MSC-derived exosomes.
The large family of BCL-2 proteins plays a well-established role in the regulation of mitochondrial apoptosis pathway, and the crosstalk between death receptor signaling and mitochondrial apoptosis. Accumulating evidence...The large family of BCL-2 proteins plays a well-established role in the regulation of mitochondrial apoptosis pathway, and the crosstalk between death receptor signaling and mitochondrial apoptosis. Accumulating evidence suggests, however, that various BCL-2 family members are also involved in the regulation of apoptosis-unrelated necrotic forms of cell death, and even non-cell death processes. In this review, we discuss the emerging role of BCL-2 family members, and in particular BIM, in the regulation of mitochondrial dynamics, morphology and energy metabolism, and associated consequences for drug-inuced necrotic cell death.
Hepatocellular carcinoma (HCC), a leading cause of cancer-related death with limited therapies, is a complex disease developing in a background of Hepatitis Virus infection or systemic conditions, such as the metabolic s...Hepatocellular carcinoma (HCC), a leading cause of cancer-related death with limited therapies, is a complex disease developing in a background of Hepatitis Virus infection or systemic conditions, such as the metabolic syndrome. Investigating HCC pathogenesis in model organisms is therefore crucial for developing novel diagnostic and therapeutic tools. Genetically engineered mouse models (GEMMs) have been instrumental in recapitulating the local and systemic features of HCC. Early studies using GEMMs and patient material implicated members of the dimeric Activator Protein-1 (AP-1) transcription factor family, such as c-Jun and c-Fos, in HCC formation. In a recent report, we described how switchable, hepatocyte-restricted expression of a single-chain c-Jun~Fra-2 protein, functionally mimicking the c-Jun/Fra-2 AP-1 dimer, results in spontaneous and largely reversible liver tumors in GEMMs. Dysregulated cell cycle, inflammation, and dyslipidemia are observed at early stages and tumors display molecular HCC signatures. We demonstrate that increased c-Myc expression is an essential molecular determinant of tumor formation that can be therapeutically targeted using the BET inhibitor JQ1. Here, we discuss these findings with additional results illustrating how AP-1 GEMMs can foster preclinical research on liver diseases with novel perspectives offered by the constantly increasing wealth of HCC-related datasets.
Hydroxychloroquine (HCQ) and chloroquine are repurposed drugs known to disrupt autophagy, a molecular recycling pathway essential for tumor cell survival, chemotherapeutic resistance, and stemness. We pursued a multi-omi...Hydroxychloroquine (HCQ) and chloroquine are repurposed drugs known to disrupt autophagy, a molecular recycling pathway essential for tumor cell survival, chemotherapeutic resistance, and stemness. We pursued a multi-omic strategy in OVCAR3 ovarian cancer and CCL218 colorectal cancer cells. Two genome-scale screens were performed. In the forward genetic screen, cell populations were passaged for 15 drug pulse-chases with HCQ or vehicle control. Evolved cells were collected and processed for bulk RNA-seq, exome-seq, and single-cell RNA-seq (scRNA-seq). In the reverse genetic screen, a pooled CRISPR-Cas9 library was used in cells over three pulse-chases of HCQ or vehicle control treatments. HCQ evolved cells displayed remarkably few mutational differences, but substantial transcriptional differences. Transcriptomes revealed multiple pathways associated with resistance to HCQ, including upregulation of glycolysis, exocytosis, and chromosome condensation/segregation, or downregulation of translation and apoptosis. The Cas9 screen identified only one autophagy gene. Chromosome condensation and segregation were confirmed to be disrupted by HCQ in live cells and organelle-free extracts. Transcriptional plasticity was the primary mechanism by which cells evolved resistance to HCQ. Neither autophagy nor the lysosome were substantive hits. Our analysis may serve as a model for how to better position repurposed drugs in oncology.
Methoxychlor (MXC) is a widely used organochlorine pesticide primarily targeting pests. However, MXC has been found to negatively impact the reproductive system of both humans and animals, triggering oxidative stress and...Methoxychlor (MXC) is a widely used organochlorine pesticide primarily targeting pests. However, MXC has been found to negatively impact the reproductive system of both humans and animals, triggering oxidative stress and apoptosis. Melatonin (MLT), an endogenous hormone, possesses various benefits, including circadian rhythm regulation and anti-inflammatory and antioxidative stress effects. Moreover, MLT plays a crucial role in the development of animal germ cells and embryos. This study aimed to investigate the impact of MLT on porcine oocytes exposed to MXC. The experimental findings revealed that 200 μM MXC had detrimental effects on the maturation of porcine oocytes. However, the addition of 10 M MLT mitigated the toxic effects of MXC. MXC induced oxidative stress in porcine oocytes, leading to an increase in reactive oxygen species and impairing mitochondrial function. Consequently, oocyte quality was affected, resulting in elevated levels of early apoptosis and DNA damage, ultimately negatively impacting subsequent embryonic development. However, the addition of MLT showed the potential to ameliorate the damage caused by MXC. In conclusion, our results suggest that MLT exhibits a protective effect against MXC-induced damage to porcine oocyte maturation.
Periodic transcriptional waves along the cell cycle ensure the accurate progression of the different cell cycle phases through the timely regulated expression of cell cycle proteins. The G1/S transition (Start) consists...Periodic transcriptional waves along the cell cycle ensure the accurate progression of the different cell cycle phases through the timely regulated expression of cell cycle proteins. The G1/S transition (Start) consists in the activation of a transcriptional program by G1 CDKs through the inactivation of Start transcriptional repressors, Whi5 and Whi7 in yeast or Rb in mammals. Here, we provide a comprehensive characterization of the transcriptional regulation of the Start repressor Whi7 in budding yeast. We found that is a cell cycle regulated gene that shows periodic expression peaking in G1. Our results demonstrate that the three cell cycle transcriptional programs related to G1 and their corresponding transcription factors are involved in the transcriptional control of . Specifically, we identified that the transcriptional regulators Swi5 and Mcm1-Yox1, which are involved in late M and early G1 expression, and the transcription factors MBF and SBF, which are responsible for G1/S expression, are able to associate and regulate the gene. In summary, in this work, we provide new mechanisms for the regulation of the Start repressor Whi7, which highlights the precise and complex control of the cell cycle machinery governing the G1/S transition.
Parasido E, Ribeiro P, Chingle RM
… +13 more, Rohwetter T, Gupta N, Avetian G, Bladelli E, Pierobon M, Chen Y, Tang Q, Schnermann M, Rodriguez O, Robbins D, Burke TR, Albanese C, Ihemelandu C
Colorectal cancer (CRC) is the third most common cancer worldwide. In the United States alone, CRC was responsible for approximately 52,550 deaths in 2023, with an estimated 153,020 new cases. CRC presents with synchrono...Colorectal cancer (CRC) is the third most common cancer worldwide. In the United States alone, CRC was responsible for approximately 52,550 deaths in 2023, with an estimated 153,020 new cases. CRC presents with synchronous peritoneal spread in 5-10% of patients, and up to 20-50% of patients with recurrent disease will develop metachronous colorectal cancer peritoneal metastatic (CRC-PM) disease. Eradication of the tumor, tumor margins and microscopic residual disease is paramount, as microscopic residual disease is associated with local recurrences, with 5-year survival rates of less than 35%. The success of resection and reduction of residual disease depends on the accuracy with which cancer cells and normal tissue can be intra-operatively distinguished. Fluorescence Molecular Imaging (IFMI) and tumor-targeted contrast agents represent a promising approach for intraoperative detection and surgical intervention. Proper target selection, the development of scalable imaging agents and enhanced real-time tumor and tumor microenvironment imaging are critical to enabling enhanced surgical resection. LGR5 (leucine-rich repeat-containing G-protein-coupled receptor 5), a colonic crypt stem cell marker and the receptor for the R-spondins (RSPO) in the Wnt signaling pathway, is also expressed on colorectal cancer stem cells (CSC) and on CRC tumors and metastases, suggesting it could be a useful target for imaging of CRC. However, there are numerous diverging reports on the role of LGR5 in CRC therapy and outcomes. Herein, we report on the synthesis and validation of a 37 amino acid RSPO1-mimetic peptide, termed RC18, that was specifically designed to access the R-spondin binding site of LGR5 to potentially be used for interoperative imaging of CRC-PM. The receptor-binding capabilities of the RC18 indicate that direct interactions with LGR5 neither significantly increased LGR5 signaling nor blocked RSPO1 binding and signal transduction, suggesting that the RSPO1-mimetic is functionally inert, making it an attractive contrast agent for intraoperative CRC-PM imaging.