Effects Of Umbilical Cord-derived Mesenchymal Stem Cells On Lewis Lung Carcinoma Chemotherapy In C57bl/6 Mice

ObjectiveThe first part was to investigate the way of isolation and culture of mesenchymal stem cells from umbilical cord, and assess their potential of differentiation. The second part was to research the effects of umbilical cord-derived mesenchymal stem cells on the growth and metastasis of lung cancer with lewis lung carcinoma animal models. The thrid part was to investigate the effect of umbilical cord-derived mesenchymal stem cells on lewis lung carcinoma chemotherapy in C57BL/6 mice.MethodsPart 1:Wharton's Jelly were isolated immediately from human umbilical cord with eye scissors and incubated for 2 weeks. The immunophenotype of fibroblast-like cells were analyzed by flow cytometry. Their potential to differentiate into adipocytes and osteocytes was detemined by oil red and alizarin reds staining. Part 2:Animal models of mouse Lewis lung carcinoma in C57BL/6 mice were established and randomly divided into NS group and MSC group (n=8). Every mouse of MSC group was injected 1 x 106 cells by tail vein at day 7,12,17 respectively. All mice were killed to observe the lung metastases number and the tumor size at day 21. Part 3:Animal models of mouse Lewis lung carcinoma in C57BL/6 mice were established and randomly divided into 3 groups (n=8):including NS group, ADM group, ADM+MSC group. Every mouse of ADM group and ADM+MSC group was injected Adriamycin 2mg/kg by intraperitoneal injection at day 1,2,3 respectively, and ADM+MSC group was injected 1×106 cells by tail vein at day 4. six days were as a course and there were total three courses of treatment. All mice were killed to detect the numerus of WBC,RBC,PLT,Hb,CK-MB and LDH at day 19. The gastrointestinal and myocardial pathology were observed by optical microscope. ResultsPart 1:From the second week after incubation, fibroblast-like cells were dominant, The second-generation cells presented homogeneous population of fibroblast-like cells. Flow cytometry analysis showed that this cell population expressed CD 105, CD 106, and did not express hematopoietic lineage markers such as CD34, CD45 or CD31 molecules. Fibroblast-like cells led to the appearance of rounded cells presenting numberous fat vacuoles in cytoplasm. The osteogenic stimulus of fibroblast-like cells led to the differentiation into osteocytes demonstrated by Alizarin Reds staining. Part 2:The average tumor weight of NS group was 4.5875±1.04g, and the tumor weight of MSC group was 4.155±1.13g. No statistical significant difference was noted between the two groups, P>0.05. The average lung metastasis number of NS group was 3.75±1.39, but the lung metastasis number of MSC group was only l.13±1.13. There was statistical significant difference between the two groups, P<0.001. Part 3:The average weight of mice in ADM+MSC group is significantly higher than that in ADM group(P<0.05). The numerus of WBC,RBC,PLT,Hb in ADM+MSC group is higher than higher that in ADM group and the numerus of CK-MB,LDH in ADM+MSC group is lower than that in ADM group. There were statistical significant difference between the two groups. The gastrointestinal and myocardial pathology indicated that MSC had an important function in repairing the injury which was cause by the chemotherapy.Conclusionl.Wharton's Jelly of umbilical cord veincontains MSC-like cells, which can be differentiated into adipocytes and osteocytes under specific culture conditions. Wharton's Jelly of umbilical cord may serve as another source of MSC for clinical use.2.Mesenchymal stem cells have no effects on the growth of lewis lung carcinoma, but can obviously inhibit tumor metastasis. 3.Mesenchymal stem cells can reduce the side reaction of chemotherapy and improve the quality of life for patients.