| Research BackgroundColorectal cancer is one of the main disease badly harmed body health of human. Incidence of this disease shows a general tendency to go up year by year. Up to the present its pathological mechanism is still not well understood. Although surgery made progress and technology of chemotherapy and radiation therapy gradually improved so that treatment level of colorectal cancer advanced, for most of colorectal cancer during evolvement period, treatment methods were not still ideality. Metastasis and recurrence are the main reason leading to the patients' death. At present patients who have suffered from metastasis are mainly treated with chemotherapy treatment.Oxaliplatin expresses an obvious advantage in the anti-cancer ability and poisonous side effect etc. The result of the treatment has been improved very greatly. The patients at the late stage of the colorectal cancer are brought the new hope. The clinical study indicates that the Oxaliplatin shows the repress function for various tumors of the colorectal cancer cell line. This repress function can be improved with the help of 5-Fu.The gene chip technique is a big breakthrough in the field of molecularbiology. It is considered the best way to study the interaction between genes, comprehensive balance control of gene group , Maintain the life phenotype, etc. It is also the most effective method to study the tumor-related genes. The gene chip can perform large-scale parallelism examination of different gene expression from different sample. The biggest advantage in the gene chip is that, it improved the traditional experiment which can only observes one or several differences between gene expressions with one test. It is widely used in the research of gene expression. ObjectiveThe main target molecules of Oxaliplatin are DNA. Oxaliplatin act on DNA through alkylation's combo and form joins of chains, then disturb the compose and copy of DNA. The combine of Oxaliplatin and DNA is very fast and it is usually finished within 15 minutes. The process of copy, the compose and separate of DNA, the compose of RNA and protein are all be disturbed.Compared with cisplatin and carboplatin, Oxaliplatin have specific cytotoxicity It was approved that for the endogenous or acquired drug-resistant cell lines at present, Oxaliplatin shows effective anticancer function both in vivo and in vitro, especially to the colorectal cancer cell line and cisplatin-resistant cell lines, and it has significant cooperation with 5-FU. Now, we can move out the copies of DNA that combine with platinum by mismatch repair, but this process will place a premium on cell apoptosis. When Oxaliplatin act on cancer cell, the compose and separate of DNA , and the compose of RNA and protein are all been disturbed. And during this process, which gene of cell will be changed and what changes will be happened would be study by us anon. Material and method1. The morphological change of SW1116 under electron microscope after Oxaliplatin is induced.SW1116 cell is planted in DMEM planting liquid, 10 % of which is FCS. When it has been planted in planting box, where the temperature is 37°C and 5% of air CO2 , for logarithm growth period, and cell density is adjusted to 1 X 106cell/ml by cell count. 40ug/ml Oxaliplatin is added into planting liquid of test group. Then SW1116 cell is planted for 12 hours contrasted with normal planting cell. 12 hours after Oxaliplatin was put into the planting liquid. Cells, either test group or controlled group are digested by pancrelipase and is Centrifugal for 10 minutes at a speed of 1000 t/m. Groups of cells are taken out and fasted with 25mol/L glutaraldehyde, routine ultra thin section, and then the morphological change of apoptosis tumor cell is observed by the transmission electron microscope.2. The changes of the gene expression table by using Oxaliplatin is detected by the gene expression table chipcDNA microarray is a kind of gene chip, its basic element is chip or micro-arrays made up of DNA or nucleic acid. The basic theory of this reaction is intercross of nucleic acid. The difference is the sample marking and examination systems. Through double-colors fluorescence marking, mRNA from different tissue is made into probe with different fluorescence marking. The probe is mixed and strictly intercrossed with the genes at the microarray. Scan the microarray with different fluorescence at different wavelength. The information of every point was put into computer. With the help of computer, the intuitionistic information of the genes is then clearly showed out.cDNA microarray can perform the parallel examination for two samples of gene express level at the same time. If using sameframe of reference, it cancarry for the analysis and comparison on gene expresses between several samples. Thus it can carry on the large-scale examination and analysis for mRNA or reverse transcription outcome cDNA come from the different individual (normal person and sufferer), different tissue, different cell period, different cell growth stage, different pathological changes, dissimilarity to stimulate (include the dissimilarity inducement, dissimilarity treatment means). Therefore, it have the extensive use in the research aspect of gene function.In this experiment 4096 cDNA clones of target genes were provided by United Gene Holdings, LTD , including 15 kinds of the cancer gene, the suppressing cancer gene, the ion passage, transporting albumen and housekeeping genes and negative contrast. And 2200 known genes, EST sequence of 1800 unknow genes, 96 feminine plant genes and blank antitheses genes. Results:During our experiment, the SW1116celFs morphological change was observed through electron microscope, and the different gene expression before and after Oxaliplatin was induced, was compared with the help of cDNA microarray. The changing on an elctron microscopy configuration and ultrastructure of the cells and the difference on gene is showed. The mechanism of tumor cytocidal induced by oxaliplatin and the molecular mechanism of the apoptosis induced by Oxaliplatin was discussed. We find out the SW1116 cell induced by oxaliplatin shows a significant morphological change of apoptosis. The protruding of quality membrane at the surface of SW1116 cells disappeared, chromatin concentrating and lying around karyotheca, mitochondrial matrix swelled, vacuolization; apoptosis body...
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