Study on Antiproliferation Effects and Cell Cycle Arrest Effects of Genistein on Cultured Immortalized Human Lens Epithelial Cell

Abstract

Purpose: : Posterior capsule opacification (PCO) remains the most common long - term complication after cataract surgery. It can be treated by Nd:YAG laser capsulotomy, however, this may lead to other complications. With the development of modern cataract refractive surgery, surgeries such as multifocal IOL implantion, which can bring better visual function, come into trends. Therefore, prevention the development of PCO seems to be more and more important.Objective: To investigate the mechanisms of antiproliferation effects of genistein with different concentration on cultured immortalized human lens epithelial cell.

Methods: : HLEC-B₃ lines were incubated with genistein 0-75mg/L for 12-72 hours,the survival rate of LEC-B₃ was determined by a trypan blue dye exclusion test;And flow cytometric analysis was employed to study the influence of genistein of different concentration on cell cycles and cell apoptosis of LEC-B₃. Reverse transcription polymerase chain reaction ( RT-PCR ) was adopted to detect mRNA expression of cell cycle protein D1, P53, and P21, while western blot was employed to detect protein expression of cyclin D1, P53 and P21.

Results: : Genistein with the concentration of 75mg/L had antiproliferative effects at 12 hours (p=0.027<0.05), and the antiproliferative effects of 12.5,25,50,75mg/L genistein had statistical significance compared with the control group at 24,48 hours. Moreover, all groups of different concentration had antiproliferative effects at 72 hours(p<0.05). The flow cytometric analysis suggested that the cell was blocked at S stage. After treated with 12.5mg/L genistein for 48 hours, apoptosis of LEC-B₃ was found. Apoptosis of LEC-B₃ was significant after treated with 50mg/L genistein for 48 hours. The rates of apoptosis were 12.72%,51.83%,59.3% respectively when treated with 6.25,12.5,25mg/L genistein for 72 hours. Expression of P21 mRNA and protein was gradually increased with the dose of genistein increased,while expression of cyclinD₁ mRNA and protein was gradually decreased. There was no significant difference on the expression of P53 mRNA and protein between the control and treated group.

Conclusions: : Genistein antagonizes HLEC-B₃ cell growth through both cell-cycle arrest and induction of apoptosis. Genistein arrests cell cycle progression at S stage, probably through the decrease of P21 expression. Moreover,this process is P53 independent.

Keywords: posterior capsular opacification (PCO) • signal transduction