1. Inhibition of PDCD6 Induces Cell Proliferation and Reduces Apoptosis in Human Epithelial Ovarian Cancer Cells
Yan Huang, Xiaohua Wu
Department of Gynecology, Cancer Center, Fudan University
Yan Huang （ ）
Correspondence: Xiaohua Wu

2. Backgrounds
Ovarian epithelial cancer is the leading killer among all gynecological malignancies.
Recent findings suggested that apoptosis and apoptosis-linked genes may play an important role in the development and progression of ovarian cancer (la Cour JM, et al. Mol Oncol. 2008).
Programmed cell death gene 6 (PDCD6), also known as apoptosis-linked gene-2 (ALG-2), is a 22 kDa penta-EF-hand type Ca2+-binding protein that was first reported by Vito in It is well recognized as an apoptotic mediator because PDCD6 expression is required for apoptosis following numerous death stimuli (Vito P, et al. Science. 1996).

3. Methods BrdU Poliferation
Design of siRNA and construction of recombi-nant plasmids
RT-PCR, Western blot
Flow cytometry
Transfection
SKOV-3 and OVCAR-3
Apoptosis
RT-PCR, Western blot
Flow cytometry
Cell cycle
RT-PCR, Western blot
Effects of cisplatin on ovarian cancer cells SKOV-3 and OVCAR-3
BrdU, Flow cytometry
Poliferation
Apoptosis
PDCD6
RT-PCR, Western blot

4. Results
RNAi inhibited PDCD6 expression in ovarian cancer cells

5. Inhibition of PDCD6 prohibited apoptosis and increased cell proliferation

6. Inhibition of PDCD6 induced cell cycle
Cell cycle phase
Transfection group
G0/G1(%)
S(%)
G2/M(%)
SKOV-3 control
75.23±1.17
16.87±0.58
7.90±1.39
SKOV-3 pRT-neg
76.73±1.53
15.40±1.21
7.87±1.45
SKOV-3 pRT-pdcd
56.77±1.48a
26.27±1.11a
16.97±2.56a
OVCAR-3 control
79.90±1.35
17.17±1.11
2.93±1.08
OVCAR-3 pRT-neg
78.27±1.00
17.30±1.13
4.43±2.05
OVCAR-3 pRT-pdcd
59.27±0.90b
22.17±1.80b
18.57±1.53b

9. Cisplatin inhibited proliferation and increased apoptosis

10. PDCD6 RNAi partly blocked the apoptotic effect and the anti-proliferative effect induced by cisplatin

11. Conclusions
1. Inhibition of PDCD6 by RNAi induced cell proliferation and cell cycle in SKOV-3 and OVCAR-3 cells by up-regulating cyclin D1, cyclin B1, cyclin E, and proliferating cell nuclear antigen (PCNA).
2. Inhibition of PDCD6 by RNAi reduced apoptosis in SKOV-3 and OVCAR-3 cells by decreasing cleaved caspase-3, cleaved caspase-7, cleaved caspase-8, Bax, death receptor 5 (DR5）and death receptor 4(DR4) and increasing Bcl-2.

12. 3. Cisplatin increased cell apoptosis and prohibited cell proliferation while the mRNA and protein expression of PDCD6 was up-regulated.
4. PDCD6 RNAi partly blocked the apoptotic effect and the anti-proliferative effect induced by cisplatin. Cisplatin may inhibit proliferation and increase apoptosis partly through PDCD6.
5. PDCD6 plays an important role in the promotion and progression of ovarian cancer. PDCD6 is a candidate as a new target for ovarian cancer treatment.

13. Thank you