| Traditional chemotherapies including doxorubicin have been widely used as efficient anticancer drugs for clinic treatment. However, recent studies reveal that tumour cells get tolerant mechanism to resistant chemotherapy. In order to get better drug efficience, the high-dose drug treatments are taken, which on the contrary leads to toxic and side effects. Hence, it’s a crucial subject to find high efficient and safe anti-tumour drugs for researchers worldwide of relevant field. According to our knowledge, the activation of nuclear factor kappa-light-chain-enhancer of activated B cells(NF-κB), is frequently encountered in tumor cells and is believed to be one of resistance mechanisms that contribute to aggressive tumor growth and resistance to chemotherapy and radiotherapy during cancer treatment.TAK1 is a member of the mitogen-activated protein kinase(MAPK) kinase kinase family and participates in the proinflammatory singnal pathway by activating JNK / p38, MAPK and NF-κB singnal pathways. Rescent clinical and experimental studies indicate that TAK1 can activate IκB kinase(IKKS), which results in the activation of NF-κB. When it comes to finding compounds with inhibiting activation of TAK1, research on a fungi-oriented dihydroxy named 5Z-7-oxozeaenol has been attracting the attention of more and more scientists. 5Z-7-oxozeaenol acts as a high efficient inhibitor for TAK1, and its common familily members such as MEKK1 and ASK1 have little effects, which indicates that 5Z-7-oxozeaenol has specific inhibition effect for TAK1.As for the cervical cancer, it still remains unknown that whether TAK1 inhibitor 5Z-7-oxozeaenol has relationship to the activation of NF- κB and to tumour apoptosis or not. In this paper cervical cancer cell was used in the model to further illustrate the anti-tumour machinism of 5Z-7-oxozeaenol via testing its effects towards TAK1 induced tumour apoptosis and the regulation of NF-κB singnal pathway. Understanding the molecular mechanisms of sensibilization function towards TAK1 of 5Z-7-oxozeaenol induction and its possible targets will provide fundamental basis for its possible potential to treat cervical cancers. The thesis mainly contains the following several parts:1. TAK1 inhibitor 5Z-7-oxozeaenol enhanced cytotoxic effects on ceivical cancer cellsAntiproliferation effect of the TAK1 inhibitor 5Z-7-oxozeaenol(5Z-7) on 4 kinds of positive HPV cervical cancer cells(He La, Si Ha, Ca Ski, ME-180) ware tested by CCK8 method, the results indicated that 5Z-7-oxozeaenol had dorminant anti-reproduction effects towards positive HPV cervical cancer cells. When thedifferent cell lines with combination of 5 μM 5Z-7 and Dox treatment for 48 h, the inhibition ratio of He La, Ca Ski, ME-18 were 60%, 70% and 85%, respectively. And all results had significant differencecompared with single Dox treatment(P<0.05). The inhibition ratio of Si Ha was 40% with combination of 2 μM 5Z-7 and Dox treatment for 48 h,, which had significant differentce compared with single 0.5 μM Dox treatment(P<0.05). The results suggested that the combination of 5Z-7 and Dox siginificantly suppressed growth of positive HPV cervical cancer cells. The results of Soft Agar Assay showed that the treatment of 0.5 μM 5Z-7 and 0.05 μM Dox combinations on He La cells for 14 d, had significant differencecompared with 0.05 μM single Dox treatment(P<0.05). The results indicated that the combinations had siginificant inhibition effects on anchorage-independent growth of cervical cancer cells. Also, it was found that combined with 5Z-7 and Dox treatment have efficient anti-proliferation effects towards negtive HPV cervical cancer cells via the same methods.2. TAK1 inhibitor 5Z-7-oxozeaenol cooperated with Dox promoted the apoptosis of cervical cancer cellsThe results of flow cytometry suggested that 5Z-7-oxozeaenol cooperated with Dox promoted the apoptosis of He La cells. And results of western blotting showed that the combinations of 5Z-7-oxozeaenol and Dox helped PARP to small pieces, that existed in positive HPV cervical cancer cells including He La,Si Ha,Ca Ski,ME-180, which suggested that 5Z-7-oxozeaenol enhanced Dox-induced apoptosis.The testing on negtive HPV cervical cancer cell line C-33-A by western blotting indicated that the combinations of 5Z-7-oxozeaenol and Dox promoted PARP to dissolve into small pieces in C-33-A cell, which meant an effect of 5Z-7-oxozeaenol inducing C-33-A cell apoptosis.3. TAK1 inhibitor 5Z-7-oxozeaenol enhanced Dox-induced chemotherapy effects on He La cells by blocking NF-κB singal pathwayThe examinations conducted by Western blotting between single Dox treatment and combinations of 5Z-7-oxozeaenol and Dox on negtive HPV cervical cancer cell line He La Results of western blotting showed that the combinations of 5Z-7-oxozeaenol and Dox on positive HPV cervical cancer cell line He La indicated that 5Z-7 blocked the activation of NF-κB, which was induced by Dox.The same text methods was used on C-33-A. And we can get the same conclusions.Together, we draw our conclusions that: 1. TAK1 inhibitor 5Z-7-oxozeaenol enhanced cytotoxic effects on ceivical cancer cells. 2. TAK1 inhibitor 5Z-7-oxozeaenol cooperated with Dox promoted the apoptosis of cervical cancer cells. 3. TAK1 inhibitor 5Z-7-oxozeaenol enhanced Dox-induced chemotherapy effects on cervical cancer cells by blocking NF-κB pathway. And which indicates that 5Z-7-oxozeaenol gets potential to be a anti-tumor drugs with bright development prospect, our researches shed light on providing fundamental basis for manufacture and development of 5Z-7-oxozeaenol. |
