| Background and Purpose:Lung cancer is still the most common and most deadly cancers. Its incidence andmortality rapid growth in the past few decades, so far, has been the first malignancymortality ranking. At present the main treatment for lung cancer are: surgery,chemotherapy, radiation therapy, targeted therapy, etc., has formed a multi-disciplinarycomprehensive treatment plan. But the5-year survival rate of lung cancer patients is stilllow. So researchers are actively exploring new treatments for lung cancer.Telomerase is a unique reverse transcriptase with the main function of elongatingand maintaining telomeres. The ribonucleoprotein consists of two main components–theRNA component(TR) containing the antisense template for telomere synthesis and thecatalytic protein. hTERT is the human telomerase catalytic subunit,and the activity isessential and rate-limiting factor component, which determines the level of telomeraseactivity. Telomerase activity is thought to play a key role in cell immortalization andcarcinogenesis, and the occurrence of lung cancer development, metastasis, and thereforehTERT is expected to become a new target for cancer therapy.hTERT main function is to maintain telomere length. In recent years many Thetelomere-independent functions were found, including: regulation of gene expression, cellgrowth and reproduction control, protection of mitochondrial function in mitochondria andso on. Meanwhile, researchers found that t he distribution of hTERT in theSubcellular:about60%in the nucleus, mitochondria20%and20%in the cytoplasm.However, this ratio is not static. Under conditions of high oxidative stress,hTERT transferred50-60%from the nucleus to the cytoplasm within24hours. Therefore,hTERT is in dynamic equilibrium in a cell. hTERT protection of mitochondrial DNA(mtDNA) to reduce mitochondrial ROS (reactive oxygen species, ROS) and thus maintaincell activity is an important mechanism for the cells are stimulated to repair itself.Nuclear factor kB (NF-kappa B) system is mainly involved in the process oftransmission of information in the body’s defense response, stress, cell differentiation andapoptosis. Virus, reactive oxygen intermediates, lipopolysaccharide stimulation canactivate NF-kappaB. The activation of NF-kappa B to enter the nucleus, can regulate thetranscription of many genes. Studies have shown that: NF-kappaB signaling pathway isclosely related with hTERT. NF-κB signaling pathway activation can be combined withhTERT promoter by nuclear translocation regulates the transcription level of hTERTcontent. In our group preliminary experiments showed that nf-kappa B inhibit caneffectively reduce the hTERT expression in lung cancer, and impact on the growth of lungcancer cells. So whether the nf-kappa B signaling pathway to cells under high ROShTERT translocation of hTERT to mitochondria has an effect? This became the focus ofour research.In this study, ammonium pyrrolidinedithiocarbamate(PDTC) to inhibit NF-kappa Bsignaling pathway. Study the nf-kappa B signaling pathway in the role of translocation ofhTERT to mitochondria in H1299lung cancer cell linesContent and methods of research:1. With Real Time rt-pcr, Western Blot technique to detect different activenf-kappaB signaling pathway in the condition of high oxidative stress to cellshTERTmRNA and protein expression2. With immunofluorescence technique to detect the impact of different activenf-kappa B signaling pathway in the condition of high oxidative stress to cells hTERTtranslocation of hTERT to mitochondria3. Using Western Blot technology to detect the relationship different active nf-kappa B signaling pathway between hTERT translocation of hTERT to mitochondriaResults:1. Real Time RT-PCR, Western Blot technique test results showed that: in thecondition of high oxidative stress hTERTmRNA and protein expression of the quantityincreased, and inhibit the nf-kappa B signaling pathway activity hTERTmRNA andprotein expression of the quantity has a downward trend;2. Immunofluorescence results indicate: Under high oxidative stress hTERT transferto the mitochondria, Inhibit the nf-kappa B signaling pathway activity reduce ranslocationof hTERT to mitochondria.3. Mitochondrial protein Western Blot results indicate: Under high oxidative stresshTERT transfer to the mitochondria, Inhibit the nf-kappa B signaling pathway activityreduce translocation of hTERT to mitochondria.4. Real Time rt-pcr, Western Blot technique test results：The nf-kappa B P65mRNAand protein expression level relatively consistent with the trend of translocation of hTERTto mitochondria.Conclusions:1. Inhibition of the nf-kappa B signaling pathway suppresses the high expression ofhTERT caused by high oxidative stress;2. Inhibition of NF-κB signaling pathway can reduce translocation of hTERT tomitochondria n;3. The major protein P65of NF-κB signaling pathway is closely associatedtranslocation of hTERT to mitochondria... |
