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Biology subjects

Pareek, S.

Publications and source records attributed to Pareek, S..

4 recordsLinked to original sources

Aerobic exercise promotes PDAC vascular normalization through S1PR1 signaling in tumor endothelial cells

Pancreatic Ductal Adenocarcinoma (PDAC) is characterized by high resistance to anti-cancer therapies. This resistance is caused in part by hypo-vascularization and dysfunctional vessels which inefficiently deliver chemotherapy. Here, we define the mechanism of aerobic exercise-induced tumor vascular remodeling and improved chemotherapy delivery and efficacy. We found that aerobic exercise was able to improve tumor vascular function and increase the number of lymphatic vessels, and these effects were associated with increased gemcitabine delivery to and efficacy against PDAC in mice. Further, exercise increased sphingosine-1-phosphate (S1P) in plasma and the activation of sphingosine-1-phosphate receptor 1 (S1PR1) in tumor endothelial cells. S1PR1 endothelial cell-specific deletion blunted the exercise-induced improvements in tumor vascular function, gemcitabine efficacy and drug concentration. Preclinical findings were validated in a patient cohort in which we found that exercise during neoadjuvant chemotherapy remodeled PDAC vasculature and improved tumor vascular function. These findings provide direct evidence that exercise increases chemotherapy delivery and efficacy by improving vascular function, defining S1PR1 as a necessary mediator of exercise-induced vascular remodeling.

cancer biology↗

Simplicity: web-based visualization and analysis of high-throughput cancer cell line screens

High-throughput drug screens are a powerful tool for cancer drug development. However, the results of such screens are often made available only as raw data, which is intractable for researchers without informatic skills, or as highly processed summary statistics, which can lack essential information for translating screening results into clinically meaningful discoveries. To improve the usability of these datasets, we developed Simplicity, a robust and user-friendly web interface for visualizing, exploring, and summarizing raw and processed data from high-throughput drug screens. Importantly, Simplicity allows for easy recalculation of summary statistics at user-defined drug concentrations. This allows Simplicitys outputs to be used with methods that rely on statistics being calculated at clinically relevant doses. Simplicity can be freely accessed at https://oncotherapyinformatics.org/simplicity/.

pharmacology and toxicology↗

Canonical Wnt signaling regulates soft palate development through mediating ciliary homeostasis

Craniofacial morphogenesis requires complex interactions among tissues, signaling pathways, secreted factors, and organelles. The details of these interactions remain elusive. In this study, we analyzed the molecular mechanisms and homeostatic cellular activities governing soft palate development to improve regenerative strategies for cleft palate patients. We have identified canonical Wnt signaling as a key signaling pathway primarily active in cranial neural crest (CNC)-derived mesenchymal cells surrounding soft palatal myogenic cells. Using Osr2-Cre;{beta}-cateninfl/fl mice, we further discovered that Wnt signaling is indispensable for mesenchymal cell proliferation and subsequently myogenesis through mediating ciliogenesis. Specifically, we identified that Wnt signaling directly regulates expression of the ciliary gene Ttll3 through {beta}-catenin/Tcf7l2 complex. Impaired ciliary disassembly leads to differentiation defects of mesenchymal cells and indirectly disrupts myogenesis through decreased expression of Dlk1, a mesenchymal cell-derived pro-myogenesis factor. Moreover, we found that restoring ciliary homeostasis rescues mesenchymal cell proliferation in Osr2-Cre;{beta}-cateninfl/fl samples. This study highlights the role of Wnt signaling in palatogenesis through controlling ciliary homeostasis, which establishes a new mechanism for Wnt-regulated craniofacial morphogenesis.

developmental biology↗

TGF-β signaling and Creb5 cooperatively regulate Fgf18 to control pharyngeal muscle development

The communication between myogenic cells and their surrounding connective tissues is indispensable for muscle morphogenesis. During late embryonic development in mice, myogenic progenitors migrate to discrete sites to form individual muscles. The detailed mechanism of this process remains unclear. Using levator veli palatini (LVP) development as a model, we systematically investigated how a distinct connective tissue subpopulation, perimysial fibroblasts, communcates with myogenic cells to regulate mouse pharyngeal myogenesis. Using single-cell RNAseq data analysis, we identified that TGF-{beta} signaling is a key regulator for the perimysial fibroblasts. Loss of TGF-{beta} signaling led to defects in perimysial fibroblasts and subsequently muscle formation in Osr2-Cre;Alk5fl/fl mice. In particular, a perimysial fibroblast-specific regulator, Creb5, interacts with TGF-{beta} signaling to enable specific activation of perimysial fibroblast-derived signals such as Fgf18. Moreover, Fgf18 supports pharyngeal muscle development in vivo and its exogenous expression can partially rescue myogenic cell numbers in Osr2-Cre;Alk5fl/fl samples, illustrating that TGF-{beta}-regulated Fgf18 signaling is required for LVP development. Collectively, our findings revealed the mechanism by which TGF-{beta} signaling achieves its specificity in defining the perimysial-to-myogenic signals for pharyngeal myogenesis.

developmental biology↗