ABSTRACT
Various c-mesenchymal-to-epithelial transition (c-MET) inhibitors are effective in the treatment of non-small cell lung cancer; however, the inevitable drug resistance remains a challenge, limiting their clinical efficacy. Therefore, novel strategies targeting c-MET are urgently required. Herein, through rational structure optimization, we obtained novel exceptionally potent and orally active c-MET proteolysis targeting chimeras (PROTACs) namely D10 and D15 based on thalidomide and tepotinib. D10 and D15 inhibited cell growth with low nanomolar IC50 values and achieved picomolar DC50 values and >99% of maximum degradation (Dmax) in EBC-1 and Hs746T cells. Mechanistically, D10 and D15 dramatically induced cell apoptosis, G1 cell cycle arrest and inhibited cell migration and invasion. Notably, intraperitoneal administration of D10 and D15 significantly inhibited tumor growth in the EBC-1 xenograft model and oral administration of D15 induced approximately complete tumor suppression in the Hs746T xenograft model with well-tolerated dose-schedules. Furthermore, D10 and D15 exerted significant anti-tumor effect in cells with c-METY1230H and c-METD1228N mutations, which are resistant to tepotinib in clinic. These findings demonstrated that D10 and D15 could serve as candidates for the treatment of tumors with MET alterations.
ABSTRACT
Sleep deficiency is a common public health problem associated with many diseases, such as obesity and cardiovascular disease. In this study, we established a sleep deprivation (SD) mouse model using a ‘stick over water’ method and observed the effect of sleep deficiency on ocular surface health. We found that SD decreased aqueous tear secretion; increased corneal epithelial cell defects, corneal sensitivity, and apoptosis; and induced squamous metaplasia of the corneal epithelium. These pathological changes mimic the typical features of dry eye. However, there was no obvious corneal inflammation and conjunctival goblet cell change after SD for 10 days. Meanwhile, lacrimal gland hypertrophy along with abnormal lipid metabolites, secretory proteins and free amino-acid profiles became apparent as the SD duration increased. Furthermore, the ocular surface changes induced by SD for 10 days were largely reversed after 14 days of rest. We conclude that SD compromises lacrimal system function and induces dry eye. These findings will benefit the clinical diagnosis and treatment of sleep-disorder-related ocular surface diseases.
ABSTRACT
Objective To construct engineered corneal epithelium from embryonic stem cells (ESCs) using Rock inhibitor combined with hypoxia-normoxia culture condition. Methods Human ESC line H1 was induced to differentiate into epithelial-like cells by addition of retinoic acid (RA) and bone morphogenetic protein 4(BMP4) in the differentiation medium under the adherent culture condition. The ESCs derived epithelial-like cells were expanded in the mixed medium of SHEM and KSFM with the mixture ratio of 1 : 2 with or without Rock inhibitor Y27632. The H1 derived epithelial-like cells were seeded on the denuded ammonic membrane to construct engineered corneal epithelium under hypoxia,normoxia and hypoxia-normoxia culture conditions,respectively. The inducted effect of ESCs into epithelial-like cells,the expansion ability of the epithelial-like cells and the characteristics of the constructed engineered corneal epithelium were evaluated by morphological observation, real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) and immunofluorescence technology. Results Compared with the control group,the relative expressions of ESCs marker Oct4 mRNA, Notch signaling pathway related factors Notch1 and Jagged1 mRNA,and Wnt signaling pathways related factors c-myc and Cyclin D1 mRNA were significantly reduced, and the relative expressions of cutaneous ectoderm markers p63 and K18 mRNA were significantly increased at day 8 after induction in the induced group,with significant differences between them (t =14.63,20.15,93.50,11.60, 19.30,18.44,22.63;all at P<0.05). Compared with the without Y27632 group,the relative expressions of p63 and K14 mRNA,Notch signal pathway receptor Notch1 and Jagged1 mRNA were significantly increased,and Wnt signaling pathways downstream targeted gene c-myc and CylinD1 mRNA were significantly decreased at day 8 after induction in the Y27632 group,with significant differences between them (t =20.29,59.22,2.90,39.59,5.32,10.14;all at P<0.05),and the relative expression of K18 mRNA in the two groups was not significantly changed(t=1.38,P>0.05). The ESCs derived epithelium and constructed under hypoxia-normoxia culture condition showed more obvious stratification and tighter cell arrangement in comparison with those cells cultured in consistent hypoxia culture condition or normoxia culture condition. Epithelial markers Pan-CK and K18 as well as epithelial progenitor cell markers p63 and K14 expressed in the whole cell layers of the ESCs derived epithelium constructed under hypoxia-normoxia culture condition. Conclusions The addition of Y27632 enhances the proliferation ability of H1 derived epithelial cells and actives Notch signaling pathway and inhibits Wnt signaling pathway. The culture and construction in the expansion medium with Y27632 under the hypoxia-normoxia culture condition can promote the stratification of H1 derived engineered corneal epithelium.