The Investigation Of The Effect Of A Small Molecule Compound A0801 On Cancer Cell Lines And Its Mechanism

Apoptosis is a normal physiology phenomenon which plays an important role in organism's development and homeostasis,and once abnormal in process of apoptosis,it will induce diseases,such as cancer. Recently,studies suggested that apoptosis plays an important role in the development of cancer as well as its ultimate invasion and metabasis.A hallmark of cancer is its resistance to natural apoptotic signals,which is typically a result of abnormally expression of key proteins in the apoptotic cascade,or of mutations in genes coding these proteins.So, through regulating the expressions and functions of these key proteins it can enhance the sensitivity of cancer to the apoptotic signals,which can induce apoptosis and suppress the growth of tumor.But most anticancer drugs target the upstream proteins in the apoptotic cascade,while rarely the executioner ones in the downstream.However,based on the executioner proteins,the Xiangya Biological Medicine Institute in Shenzhen synthesized a new small molecule compound named A0801. Here we aimed to investigate the effects of the compound on cancer cells and primarily explore its mechanism.OBJECTIVE To study the effects of compound A0801 on the proliferation of the leukemia cell lines(HL-60 and K562),liver cancer cell line(HepG-2),lung adenocarcinoma cell line(A549),and neuroblastoma cell line(SK-N-SH),and to explore its mechanism preliminary.METHODS The effects of A0801 on cancer cells HL-60,K562,A549, HepG-2 and SK-N-SH were studied by MTT assay.The morphology of the cells was observed by the Wright's-Giemsa staining and Hochest-33258 staining.The enzyme activity was determined using the kit to study the effect of compound A0801 on the activity of caspase-3. RT-PCR assay was used to study the mRNA expression of the apoptosis related gene such as Bcl-xl and Survivin in both HepG-2 and HL-60 cell lines treated by A0801 for different time,and the cell cycles of HepG-2 and HL-60 were determined by flow cytometry.RESULTS(1) The result of the MTT assay showed that compared with peripheral blood mononuclear cells(PBMNC),the proliferation of cancer cells can be inhibited by the A0801 in a manner of time-does dependent, especially for the leukemia cell line HL-60.The IC₅₀ values for the cell death induction for A0801 versus HL-60 cells were 2.21±0.47μg/ml, 1.50±0.10μg/ml and 0.94±0.10μg/ml after treated for 24h,48h and 72h respectively.(2) The cytoplasma bubbling and chromatin condensation were observed in Wright's-Giemsa-stained HepG-2 cells,and hyperchromatic nuclear was observed in Hochest-33258-stained cells.(3) It was observed that compared with the control group,the caspase-3-like activity reached the highest level in HepG-2 cells after treated by A0801(10μg/ml) for 24h.Although there was a downward trend after treated for 48h and 72h,the level of the caspase-3-like activity is still higher than that of control group.(4) The flow cytometry assay indicated that compared with the control group,after treated with A0801 for 24h, the number of cells in G1 phase increased significantly,while in S phase and G2 phase the number was significantly reduced.CONCLUSION(1) The compound A0801 can significantly inhibit the proliferation of HL-60,K562,A549,HepG-2 and SK-N-SH cells in a time-does dependent manner,while there was almost no obvious inhibition to PBMNC.(2) The compound A0801 can induce apoptosis by activating caspase-3 in HepG-2 cells.(3) The compound A0801 can inhibit the proliferation of HepG-2 cells through G1 phase arrest.