Objective To suppress the proliferation of lens epithelial cells (LECs) is a primary goal in prevention of after cataract. Recent study demonstrated an effective inhibition of elemene(Ele) on tumor cells. Present study was to investigate the effects of Ele on proliferation and cell cycle of human LECs B3 (HLE-B3). Methods Recombinant human basic fibroblast growth factor(rhbFGF) was utilized to induce proliferation of HLE-B3. Proliferative HLE-B3 was incubated with 80 mg/L Ele in CO_2 incubator for 24 hours. Then the inhibitory effects of Ele on proliferation of HLE-B3 was evaluated by methyl thiazolyl tetrazolium(MTT). The effect of Ele on HLE-B3 morphology was observed under the optical microscope. The effect of Ele on HLE-B3 cell cycle was analyzed by flow cytometer(FCM). Results MTT test showed that the optical density (OD) value of rhbFGF group was remarkably higher than that of control group(0. 599 0 ± 0. 053 1 versus 0. 409 1 ± 0. 042 2) (P ＜ 0. 01), and that of Ele group(0. 450 0 ±0. 061 4) was obviously declined in comparison to rhbFGF group(P ＜0. 01) . The inhibitory rate of Ele was 24.90 %. In proliferation group, the number of HLE-B3 was increased with the normal cell structure and abundant cytoplasm under the optical microscope. However, in Ele group, the number of HLE-B3 was evidently decreased with less cytoplasm, undistinguished cell structure, condensed and aggregated nucleuses. The result of flow cytometer showed that the percentage of HLE-B3 in G_1 phase in rhbFGF group was 42. 062% ± 1. 270% and that in control group was 46. 422% ±3. 765% with a significant difference(P ＜ 0. 05). HLE-B3 in G_1 phase in Ele group (60. 665% ±2.069%) was evidently increased in comparison with rhbFGF group (P ＜ 0. 01). HLE-B3 in S phase in rhbFGF group compared with control group was increased (51.647% ±1.123% versus 31.842% ± 2. 798%) (P ＜ 0. 01), but that in S phase in Ele group(30. 222% ±3.429%) was lower than rhbFGF group (P ＜ 0. 01). HLE-B3 in G_2 phase in rhbFGF group was decreased in comparison with control group (6. 288% ± 0. 966% versus 21. 735% ± 3. 806%, P ＜ 0. 01), and that in G_2 phase in Ele group (9. 112% ± 1. 659%) compared with proliferation group was increased (P ＜ 0. 01). Conclusion Ele could alter the cell cycle of HLE-B3 and effectively inhibit the HLE-B3 proliferation induced by rhbFGF. Ele may be a reliable and effective drug for prevention and treatment of after cataract.

Objective:To observe the effects of miR-21 knockout on proliferation and drug resistance in K562/G01 cells, and to preliminarily explore the mechanism of imatinib sensitivity by knocking out miR-21 in K562/G01 cells.Methods:Using CRISPR/Cas9 to knock out the miR-21 gene in K562/G01 cells, and single-cell-derived clones of miR-21 knockout were obtained by genomic DNA PCR screening, Sanger sequencing, and real-time PCR. We used MTT and cell colony formation assays to assess the cell proliferation, and determined imatinib sensitivity by MTT assay and Annexin-Ⅴ-APC/7-AAD double staining flow cytometry. Using western blot, we examined the potential mechanisms affecting imatinib sensitivity by knocking out miR-21 in K562/G01 cells.Results:Three miR-21 knockout K562/G01 single-cell-derived clones were successfully constructed. The mutation efficiency mediated by CRISPR/Cas9 was 7.12%-8.11%. MiR-21 knockout inhibited the proliferation of K562/G01 cells; the clone formation rates of WT and 1#, 2#, 6# K562/G01 single-cell clones were (57.67±8.25) %, (26.94± 5.36) %, (7.17±2.11) %, (31.50±3.65) %, respectively. MiR-21 knockout increased the sensitivity of K562/G01 cells to imatinib, IC 50 of imatinib in WT, and 1#, 2#, 6# K562/G01 single-cell clones were (21.92±1.36) μmol/ml, (3.98±0.39) μmol/ml, (5.38±1.01) μmol/ml, (9.24±1.36) μmol/ml. After the knockout of miR-21, the activation of PI3K/Akt signaling molecules was inhibited, while the expression of P210 BCR-ABL and p-P210 BCR-ABL was downregulated; however, the expression of PTEN was not affected. Conclusion:The knockout of miR-21 can suppress cell proliferation and improve sensitivity to imatinib in K562/G01 cells, which may be achieved by inhibiting the PI3K/AKT signaling pathway and BCR-ABL expression.