Vimentin regulates differentiation switch via modulation of keratin 14 levels and their expression together correlates with poor prognosis in oral cancer patients

Abstract

Vimentin is an intermediate filament protein, predominantly expressed in cells of mesenchymal origin, although its aberrant expression is seen in many carcinomas during epithelial mesenchymal transition. In cancer, vimentin expression is associated with the transition from a more differentiated epithelial phenotype to a dedifferentiated state. In view of the perceived role of keratins (Ks) as regulators of differentiation in epithelia, it was important to understand whether vimentin modulates differentiation through the reprogramming of keratins, in transformed cells. To address this, vimentin was stably downregulated in oral cancer derived cells. Further, global keratin profiling was performed after high salt keratin extraction. K5/K14 pair was found to be significantly downregulated, both at protein and mRNA levels upon vimentin downregulation. The previous study from our laboratory has shown a role of the K5/K14 pair in proliferation and differentiation of squamous epithelial cells. Vimentin depleted cells showed an increase in the differentiation state, marked by an increase in the levels of differentiation specific markers K1, involucrin, filaggrin and loricrin while its proliferation status remained unchanged. Rescue experiments with the K5/K14 pair overexpressed in vimentin knockdown background resulted in decreased differentiation state. ΔNp63 emerged as one of the indirect targets of vimentin, through which it modulates the expression levels of K5/K14. Further, immunohistochemistry showed a significant correlation between high vimentin-K14 expression and recurrence/poor survival in oral cancer patients. Thus, in conclusion, vimentin regulates the differentiation switch via modulation of K5/K14 expression. Moreover, vimentin-K14 together may prove to be the novel markers for the prognostication of human oral cancer.

Extracellular vesicles derived from MSCs activates dermal papilla cell in vitro and promotes hair follicle conversion from telogen to anagen in mice

“…Western blot analysis was performed as described 73 . Whole-cell or EV or dorsal skin tissue lysates were prepared in SDS lysis buffer (62.5 mM Tris pH 6.8, 2% SDS, 0.1% β-mercaptoethanol, 10% glycerol, and protease inhibitor cocktail (Sigma, USA).…”

Macrophage-Derived Extracellular Vesicle Promotes Hair Growth

“…The dorsal skin of all the groups was fixed in 10% formalin and assessed with hematoxylin and eosin (H&E) staining [25]. The number of HFs were counted.…”

Keratin 5/14‑mediated cell differentiation and transformation are regulated by TAp63 and Notch‑1 in oral squamous cell carcinoma‑derived cells

“…After 6-8 weeks, the animals were sacrificed so that the mean tumor diameter did not exceed 1.2 cm, as described in the AAAlAC guidelines for Animal Welfare in Cancer research (14). The mice were euthanized using CO 2 method and the tumor was removed (18).…”

“…The blot was then washed thrice with TBST [0.1% Tween-20 (v/v), 150 mM NaCl, 10 mM Tris-HCl pH 8.0] followed by incubation with horseradish peroxidase (HrP)-conjugated secondary antibody (anti-mouse; A4416 or anti-rabbit; A-0545; Sigma-Aldrich) for 1 h at rT on a rocker followed by TBST washes. The blots were developed using ECl chemiluminescence reagent (WesternBright™ ECl; Advansta, East Sussex, uK) according to the manufacturer's protocol (18). The primary antibodies for K14 (1:8,000; mouse monoclonal, clone ll002; cat.…”