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Shah, J. V.

Publications and source records attributed to Shah, J. V..

2 recordsLinked to original sources

Piezo mechanosensory channels regulate centrosome integrity

Piezo1 and 2 are evolutionarily conserved mechanosensory cation channels known to function on the cell surface by responding to external pressure and transducing a mechanically activated Ca2+ current. Here we show that both Piezo1 and 2 also exhibit concentrated intracellular localization at centrosomes. Both Piezo1 and 2 loss-of-function and Piezo1 activation by the small molecule Yoda1 produced supernumerary centrosomes due to inappropriate centriole disengagement. Using a centrosome-localized GCaMP Ca2+-sensitive reporter, we show that perturbations in Piezo modulate Ca2+ local concentration at centrosomes. We designed a photoactivable Yoda1 analog (caged-Yoda1) and revealed that its photoactivation specifically at centrosomes leads to rapid premature centriole disengagement within minutes. We identified the sorting nexin Snx5, which is involved in endocytic uptake and trafficking, as a protein-interactor with the conserved Piezo C-terminal domain, and Snx5 also co-localizes with Piezo1 and 2 at centrosomes. Moreover, inhibition of Polo-like-kinase 1 (PLK1) abolishes Yoda1-induced centriole disengagement. Collectively, these data suggest that Piezo1 and 2 in pericentrosomal endosomes control centrosome integrity, likely by maintaining local Ca2+ within a defined range through mechanotransduction of cell intrinsic forces from microtubules.

cell biology↗

Extracellular vesicle molecular signatures characterize metastatic dynamicity in ovarian cancer

Late-stage diagnosis of ovarian cancer drastically lowers 5-year survival rate from 90% to 30%. Early screening tools that use non-invasive sampling methods combined with high specificity and sensitivity can significantly increase survival. Emerging research employing blood-based screening tools have shown promise in non-invasive detection of cancer. Our findings in this study show the potential of a small extracellular vesicle (sEV)-derived signature as a non-invasive longitudinal screening tool in ovarian cancer. We identified a 7-gene panel in these sEVs that overlapped with an established tissue-derived metastatic ovarian carcinoma signature. We found the 7-gene panel to be differentially expressed with tumor development and metastatic spread. While there were quantifiable changes in genes from the 7-gene panel in plasma-derived sEVs from ovarian cancer patients, we were unable to establish a definitive signature due to low sample number. The most notable finding was a significant change in the ascites-derived sEV gene signature that overlapped with that of the plasma-derived sEV signature at varying stages of disease progression. Taken together our findings show that differential expression of metastatic genes derived from circulating sEVs present a minimally invasive screening tool for ovarian cancer detection and longitudinal monitoring of molecular changes associated with progression and metastatic spread.

cancer biology↗