Study About Sonodynamic Therapy Affecting Nuclear Protein Expression And Enzyme Activity Of S180 Ascitic Tumor Cell

The experiment was on the basis of researches about Sonodynamic therapy having two antitumor modes (direct killing and induced apoptosis) for proliferate activity of tumor cell. We adopted the focused ultrasound with a frequency of 1.34MHz and an intensity of 3W/cm~2 activating the Hematoporphyrin to treat ascitic S180 tumor cell. We got treated tumor cells at different times after the treatment, and used immunohistochemistry to detect the dynamic change of intranuclear proteins and enzymes, which have the important correlation with tumor cell in proliferation activity, apoptosis regulation, gene duplication ability, gene transcription activity and protein synthesize. Finally, we used the professional image analysis and statistics software to carry on processing for the changes of proteins and enzymes expression. We obtained the difference significance from experiment result and gave the reasonable explanation about biology significance of the changes. The changes of different biology indexes also indirectly reflected that Sonodynamic therapy influenced intranuclear gene expression activity. In a word, the experimental research accumulated scientific and helpful data for illuminating the mechanism of Sonodynamic therapy. The experimental results were as follow:1. The molecular biology research indicated that the AgNORs (Agenophilic nucleolar organizer regions associated protein) was a highly phosphorylative and acidic nonhistone, which specially combined with the rRNA gene having active transcription ability. The changes in expression quantity and morphology of this protein may indirectly reflect the active level of rDNA transcription and some changes in the structure and function of nucleolar organizer regions. The experimental result indicated that the Sonodynamic therapy had an obviously inhibitory effect, which caused the proliferation activity of tumor cell to be remarkably suppressed.2. Proliferating cell nuclear antigen (PCNA) is the auxiliary protein of DNA polymerase delta, and it is also the necessary nuclear protein for DNA synthesis in eukaryotes. Its synthesis and expression are concerned with the cellular proliferation state. In addition, it also has an important effect during the repair process of DNA. The experimental result indicated that the Sonodynamic therapy has the remarkablyinhibitory effect for the PCNA expression. The effect May directly affect the process of intranuclear DNA synthesis, DNA duplication and DNA repair, and thus it further suppressed the proliferation activity in tumor cell.3. The mutant p53 protein has lost the negatively regulative ability for cell proliferation and cell cycle, the inhibitory effect for cell malignant transformation and the promotive effect for cell apoptosis. Moreover, it also has disturbed the normal function of wild p53 subunit. It obtains the ability of cell malignant transformation and new biological function of tumor protein. The experimental result indicated that the Sonodynamic therapy had an obviously inhibitory effect for the expression of mutant p53 protein in SI80 ascitic tumor cell.4. The high expression of c-myc protein was discovered in many kinds of human cells. It can promote the proliferation and differentiation of cell. Researches in recent years indicated that c-myc protein also participated in the regulation of cell apoptosis. C-myc gene is a main gene for the regulation in cell cycle. It can adjust two polarity processes, cell proliferation and cell death. When c-myc signal transduction system is activated, and if there are enough growth factors in the culture environment, then cell begin to proliferate and divide. Otherwise, the c-myc protein will induce cell to apoptosis. The experimental result indicated that the Sonodynamic therapy might inhibit the expression of c-myc protein in SI80 ascitic tumor cell. The changes in the expression of c-myc protein may further induce tumor cell to apoptosis.5. C-jun protein and c-fos protein are a kind of nuclear transcription factor, which are correlating with the transcription activity of many oncogenes. They have a high expression in majority tumor cells. The two proteins can form homologous or heterologous dimer through the leucine zipper structure, and they constitute transcriptional regulative protein AP-1. Ap-1 protein acts on the Ap-1 union spot in regulative sequence of the target gene, and it has the importantly regulative function to the cell proliferation and differentiation. The experimental result indicated that the Sonodynamic therapy has an obviously inhibitory effect to the expression of c-jun and c-fos protein. The low expression quantity of the two proteins may affect the transcriptional activities of some correlated oncogene, which further affect the hearty proliferation of tumor cell.6. Telomere as the clock of cell mitosis has an important effect for cell proliferation, cell aging and cell apoptosis. Telomerase as a kind of reverse transcriptase plays theextremely vital role to maintain the length of telomere and repair broken chromosome terminal. Telomerase activity is on the high level in majority tumor cells, so tumor cells obtain strong proliferation ability. The experimental result indicated that the Sonodynamic therapy obviously inhibited telomerase activity, which further affect the repair process of broken chromosome and induced tumor cell to death.7. The DNA topoisomerase II is a kind of nuclear enzyme having ability of regulating the DNA three-dimensional structures. It directly participates and affects the processes of DNA duplication, repair, transcription, translation and mitosis. At the same time, it is also the important target spot for many anticancer drugs. Through suppressing normal function of the enzyme, it can change the nucleic acid configuration and cause the nucleic acid to break, which further promotes tumor cell to death. The experimental result indicated that the Sonodynamic therapy had the remarkable inhibitory effect to the activity of DNA topoisomerase Ila. It further suppressed the normal function of DNA topoisomerase Ila and accelerated the death or apoptosis process of hurt tumor cells.