Project description:Autophagy plays important roles in malignant pathogenesis and drug resistance. We used medicinal chemistry approaches to generate a series of novel agents that inhibit autophagic degradation. ROC-325 was selected as a lead compound for further evaluation. Comprehensive in vitro and in vivo studies were conducted to evaluate the selectivity, tolerability, and efficacy of ROC-325 in preclinical models of renal cell carcinoma (RCC). ROC-325 exhibited superior in vitro anticancer effects than the existing autophagy inhibitor hydroxychloroquine in 12 different tumor models with diverse genetic backgrounds. Focused studies of the mechanism of action and efficacy of ROC-325 in RCC cells showed that drug treatment induced hallmark characteristics of autophagy inhibition including accumulation of autophagosomes with undegraded cargo, lysosomal deacidification, p62 stabilization, and disruption of autophagic flux. Subsequent experiments showed that ROC-325 antagonized RCC growth and survival in an ATG5/7-dependent manner, induced apoptosis, and exhibited favorable selectivity. Oral administration of ROC-325 to mice bearing 786-0 RCC xenografts was well tolerated, significantly more effective at inhibiting tumor progression than HCQ, and inhibited autophagy in vivo. We used microarrays to determine gene expression changes following 24 h treatment with ROC-325 in RCC cell lines and identified differentially expressed genes.
Project description:Peroxisome proliferator-activated receptor-gamma (PPARg) regulates the interface between cellular lipid metabolism, redox status and organelle differentiation. Following conditional prostatic epithelial knockout of PPARg in mice we observed focal hyperplasia of the epithelium which developed to mouse prostatic intraepithelial neoplasia (mPIN), becoming progressively more severe with time. We selectively knocked down PPARg2 isoform in wild-type mouse prostatic epithelial cells and examined the consequences of this in a tissue recombination model. Histopathologically the results resembled the conditional PPARg KO mouse prostates. Electron microscopy showed accumulated defective lysosomes and autophagic vacuoles in both of PPARg- and g2- deficient cells. Gene expression profiling indicated a major dysregulation of cell cycle control and metabolic signaling networks related to peroxisomal and lysosomal maturation, lipid oxidation and degradation. We conclude that PPARg maintains the maturation and turnover of peroxisomes and lysosomes in prostate epithelium. Disruption of PPARg signaling results in autophagy and oxidative stress during mPIN pathogenesis. The mPrE-PPARg knockout and mPrE-PPARg2 shRNA cells were compared to wildtype mPrE cells. Time (3 days culture) and cell types (x 4) were tested.
Project description:Mathematical modeling of regulatory T cell effects on renal cell carcinoma treatment
Lisette dePillis 1, , Trevor Caldwell 2, , Elizabeth Sarapata 2, and Heather Williams 2,
1.
Department of Mathematics, Harvey Mudd College, Claremont, CA 91711
2.
Harvey Mudd College, Claremont, CA 91711, United States, United States, United States
Abstract
We present a mathematical model to study the effects of the regulatory T cells (Treg) on Renal Cell Carcinoma (RCC) treatment with sunitinib. The drug sunitinib inhibits the natural self-regulation of the immune system, allowing the effector components of the immune system to function for longer periods of time. This mathematical model builds upon our non-linear ODE model by de Pillis et al. (2009) [13] to incorporate sunitinib treatment, regulatory T cell dynamics, and RCC-specific parameters. The model also elucidates the roles of certain RCC-specific parameters in determining key differences between in silico patients whose immune profiles allowed them to respond well to sunitinib treatment, and those whose profiles did not.
Simulations from our model are able to produce results that reflect clinical outcomes to sunitinib treatment such as: (1) sunitinib treatments following standard protocols led to improved tumor control (over no treatment) in about 40% of patients; (2) sunitinib treatments at double the standard dose led to a greater response rate in about 15% the patient population; (3) simulations of patient response indicated improved responses to sunitinib treatment when the patient's immune strength scaling and the immune system strength coefficients parameters were low, allowing for a slightly stronger natural immune response.
Keywords: Renal cell carcinoma, mathematical modeling., sunitinib, immune system, regulatory T cells.
Project description:Background: Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide with limited treatment options. The intricate pathogenesis of dysregulated lipid metabolism leading to the development of DKD remains obscure. Lipophagy, which refers to the autophagic degradation of intracellular lipid droplets, has been found to be impaired in DKD, resulting in renal tubule dysfunction and ectopic lipid deposition (ELD). The lipotoxity in renal tubules is closely related to the pathogenesis of DKD. Therefore, it is crucial to develop effective and safe agents that can restore autophagic flux and lipophagy in renal tubules for potential preventive interventions. Purpose: This study seeks to investigate the preventive effect of sodium butyrate (NaB) on ELD in the progression of DKD and elucidate the underlying mechanisms involved.Methods: The beneficial effects of NaB were investigated in glucolipotoxicity (GLT)-stimulated HK-2 cells and the streptozotocin (STZ) injection combined with a high-fat diet induced DKD model mice. Additionally, we managed to silence transcription factor EB (TFEB) in HK-2 cells and establish the renal specific silence model by retrograde ureteral infusion of AAV9-shTFEB in mice. We investigated the expression profile of RNAs in HK-2 cells through. The mechanism of NaB is demonstrated by RNA sequencing (RNA-seq), pulldown MS assay, SPR experiments etc.Results: Our findings revealed that serum butyrate level is reduced in DKD patients and is statistically correlated with urinary protein excretion and eGFR. Sodium butyrate (NaB) dose-dependently improved lipid deposition in HK-2 cells and renal tubular epithelial cells of DKD model mice. This effect may be attributed to the promotion of TFEB dephosphorylation, as NaB can directly interact with PPP2R1A to activate PP2A phosphorylation activity. Therefore, NaB may play a role in improving renal lipid deposition in DKD through the PP2A-TFEB pathway. Conclusion: NaB acts as a PP2A-TFEB axis activator that restores lipophagy to ameliorate ELD and renal dysfunction in DKD.
Project description:Non-coding RNAs play an important role in the pathogenesis of human malignancies. So far, microRNAs have been investigated in detail in clear cell renal cell carcinoma, but the knowledge about other small non-coding RNAs like snoRNA, tRNA and piRNA remains small. There is increasing evidence that these non-coding RNAs are also involved in regulation of gene expression, and we therefore performed small RNA sequencing in a cohort of 18 corresponding normal and malignant tissue samples from patients with clear cell renal cell carcinoma. We observed differential expression of microRNAs, but also some dysregulated tRNA and snoRNA in clear cell renal cell carcinoma tissue
Project description:Alzheimer’s disease (AD), and lysosomal dysfunction has been implicated in AD pathogenesis. We found, by examining cells stably expressing each APOE isoform, that APOE4 increases lysosomal trafficking, accumulates in enlarged lysosomes and late endosomes, alters autophagic flux and the abundance of autophagy proteins and lipid droplets, and alters the proteomic contents of lysosomes following internalization. We investigated APOE-related lysosomal trafficking further in cell culture, and found that APOE from the post-Golgi compartment is degraded through autophagy. We found that this autophagic process requires the lysosomal membrane protein LAMP2 in immortalized neuron-like and hepatic cells, and in mouse brain tissue. Several macroautophagy-associated proteins were also required for autophagic degradation and internalization of APOE in hepatic cells. The dysregulated autophagic flux and lysosomal trafficking of APOE4 that we observed suggest a possible novel mechanism that might contribute to AD pathogenesis.