AIM: To investigate the potential toxic effects of paclitaxel(PTX)on the proliferation, apoptosis, cell cycle, morphology, and blood-retinal barrier(BRB)of human retinal pigment epithelial cells(ARPE-19).

METHODS: ARPE-19 cells were cultured in vitro and divided into two groups: Control group(Control)and drug plus group(PTX). ARPE-19 cells were treated with different concentrations of PTX(0.005, 0.05, 0.5, 5mg/L)for a certain period of time(12, 24, 36, 48, 72h), and CCK8 assay and flow cytometry were used to detect the effects of drug on proliferation and apoptosis of ARPE-19 cells at different concentrations and time points. The same time, the cell cycle was detected by flow cytometry. Morphological changes of cells were observed by immunofluorescence. Expressions of apoptosis-related proteins and barrier function-related proteins were detected by Western blot. The effect of the drug on the cell barrier was measured by measuring the transepithelial resistance of the cells.

RESULTS: PTX reduced the proliferation ability of ARPE-19 cells. After 36h of treatment with low concentration of 0.005mg/L paclitaxel, cell proliferation began to be affected. At the same time, PTX accelerated cell apoptosis was dependent on drug concentration and time. Flow cytometry showed that the cells were arrested in the G2-M phase. In addition, PTX causes significant morphological changes in cells, with normal cells fusiform or irregular. In the PTX group, the number of cells decreased and the cell shape tended to be round. PTX affected retinal barrier function, and the transepithelial resistance of cells was significantly decreased after treatment, and the expression of tight junction proteins ZO-1 and Occludin were significantly decreased compared with the control group(P<0.05). The expression levels of Cleaved-caspase-3 and Bax were significantly increased compared with the control group, while the expression levels of Bcl-2 were significantly decreased(P<0.05)and was dependent on drug concentration and time.

CONCLUSION: PTX can affect the proliferation and apoptosis of ARPE-19 cells, and it depends on time and concentration. In addition, PTX affected the cell cycle and morphology of ARPE-19 cell. At the same time PTX can destroy the barrier function of the retina,suggesting that anti-tumor drugs have a potential toxic effect on the retina.