TCS 401 is a selective inhibitor of protein-tyrosine phosphatase 1B (PTP1B; Ki = 0.29 µM)

TCS 401 promoted the proliferation and expression of cyclin A and cyclin D1 in RPE cells. TCS 401 induced RPE cells to differentiate toward better contractility and motility. A migration assay proved that inhibiting PTP1B improved the migratory activity of RPE cells. TCS 401 activated extracellular signal-regulated kinase (Erk) and protein kinase B (Akt) phosphorylation. Pretreatment with PD98059 and LY294002 abolished TCS 401-induced activation of Erk, Akt, cell proliferation, and cell migration[1].

From the cultured RPE cells treated with TCS 401, cell proliferation was assessed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetracolium bromide assay, and the protein expression levels of cyclin A and cyclin D1 were determined. The effect of TCS 401 on cell differentiation was confirmed by immunostaining for α-smooth muscle actin and by western blot. Cell migration activity and PTP1B signaling mechanism were determined. Migration Assay was used to evaluate cell migration activity. PTP1B signaling mechanism was determined by use of PD98059 and LY294002[1].