Preliminary Study On The Suppressive Effect Of Culture Supernatant Of Antler Stem Cells On The Migration And Invasion Of Breast Cancer Cells And Its Molecular Mechanism

Jilin province is the hometown of sika deers and deer breeding is one of her characteristic agricultural industries.The annual number of antler-producing deers in Jilin is about 500000,accounting for about one third of the national stock.Antler,as a traditional Chinese medicine,has been used for thousands of years in China and plays an important role in the field of traditional Chinese medicine.Antler is the only mammalian organ that can completely regenerate periodically.The complete regeneration of an antler depends on proliferation and differentiation of antler stem cells,and the fast-growing antler tissue never develops tumors,suggesting that there is a close association between antler stem cells and the tumor-free situation.Cancer has become one of the main killers to human health.As the key reason for the cancer-related deaths,tumor metastasis has always been a difficult problem of cure.At present,it is believed that the expression level of cancer-related genes in a tumor cell changes under the action of carcinogenic factors.This change may lead to an increase in malignancy of a tumor cell as characterized at least as aberrant reorganization of the cytoskeleton,cell shape change and enhanced cell migratory and invasive potentials.These aberrations may partially resemble the phenotype of the epithelial-mesenchymal transition,which is a cellular event key to metastasis.Epithelial-Mesenchymal Transition(EMT)plays key roles in governing tumor cell differentiation,tumor cell migration and tumor metastasis,and it is strictly regulated by EMT-related genes.The expression level of these EMT-related genes will change under the stimulation of various environmental and genetic cues,and as a consequence,the EMT event progresses.These complex changes in gene expression can be monitored by a powerful method like transcriptomic analysis,providing informatic support for related studies.In this study,the MDA-MB-231 human breast cancer cell line was used.The cell line has a high metastatic potential and is believed to have had an EMT event occurred.Upon the success in the preparation of antler stem cells,the culture supernatant of antler stem cells(CSASC)was harvested to treat the MDA-MB-231 cells.By performing the wound healing assay and the Transwell invasion assay,I found that CSASC treatment attenuated the migratory and invasive potentials of the MDA-MB-231 cells.At the same time,by performing the CCK8 assay,I found that CSASC treatment attenuated the proliferative potential of the MDA-MB-231 cells;in contrast,CSASC treatment had no effect on the proliferative potential of the bone marrow stromal cells(BMSCs),suggesting that CSASC prefers to attenuate the proliferative potential of tumor cells rather than that of non-tumor cells(e.g.BMSCs),although BMSCs also have a high proliferative potential.Further,by using the RNAseq technique,I uncovered a transcriptomic change in the MDA-MB-231 cells before and after CSASC treatment,and by performing GO(Gene Ontology)and KEGG(Kyoto Encyclopedia of Genes and Genomes)annotation analyses,I found a strong association between the differentially expressed genes(DEGs)and cell migration and invasion.In addition,I found some EMT-related DEGs in MDA-MB-231 cells by comparing the RNAseq data of MCF7 breast cancer cells with that of MDA-MB-231 cells.So I found that the expression level of some key EMT related genes was also altered(for examples,SNAIL1 was downregulated whereas CDH1 was upregulated),suggesting that CSASC treatment attenuated the molecular trait of EMT in the MDA-MB-231 cells.Finally,by using the RT-q PCR technique,I validated the differential expression of these key EMT related DEGs and thus confirmed the reliability of the transcriptomic data.In summary,CSASC may exert an inhibitory effect on the migratory and invasive potentials of the MDA-MB-231 cells through altering the expression of some key EMT related genes and other necessary but uncharacterized genes.My thesis may provide a new idea for the study of the functional correlation between antler stem cells and anti-tumor(anti-metastasis)in the future.