Cigarette smoke‑induced malignant transformation via STAT3 signalling in pulmonary epithelial cells in a lung‑on‑a‑chip model

Background Chronic obstructive pulmonary disease(COPD)is a severe public health problem.Cigarette smoke(CS)is a risk factor for COPD and lung cancer.The underlying molecular mechanisms of CS-induced malignant transformation of bronchial epithelial cells remain unclear.In this study,we describe a lung-on-a-chip to explore the possible mechanistic link between cigarette smoke extract(CSE)-associated COPD and lung cancer.Methods An in vitro lung-on-a-chip model was used to simulate pulmonary epithelial cells and vascular endothelial cells with CSE.The levels of IL-6 and TNF-αwere tested as indicators of inflammation using an enzyme-linked immune sorbent assay.Apical junction complex mRNA expression was detected with qRT-PCR as the index of epithelial-to-mesenchymal transition(EMT).The effects of CSE on the phosphorylation of signal transduction and transcriptional activator 3(STAT3)were detected by Western blotting.Flow cytometry was performed to investigate the effects of this proto-oncogene on cell cycle distribution.Results Inflammation caused by CSE was achieved in a lung-on-a-chip model with a mimetic movement.CSE exposure induced the degradation of intercellular connections and triggered the EMT process.CSE exposure also activated the phosphorylation of proto-oncogene STAT3,while these effects were inhibited with HJC0152.Conclusions CSE exposure in the lung-on-a-chip model caused activation of STAT3 in epithelial cells and endothelial cells.HJC0152,an inhibitor of activated STAT3,could be a potential treatment for CS-associated COPD and lung cancer.

Preparation of chitosan-Epigallocatechin-3-O-gallate nanoparticles and their inhibitory effect on the growth of breast cancer cells

In this paper,we prepared the nanoparticle drug carrier system between nanoparticles chitosan and Epigallocatechin-3 O-gallate(EGCG)for breast cancer cell inhibiting application.For this drug carrier system,chitosan acts as a carrier and EGOG as a drug.Which were systematically characterized and thoroughly evaluated in terms of their inhibition rate and biocompatibility.We also did a cell scratch test and the result indicated that the chitosan EGCG nanoparticles have inhibitory effect on the growth of breast cancer cells.The inhibition rate could reach up to 21.91%.This work revealed that the modification of nanopartidles paved a way for specific biomedical applications.