The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene ...The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.展开更多
Objective:Glioma is a highly invasive tumor,frequently disposed in essential areas of the brain,which makes its surgical excision extremely difficult;meanwhile adjuvant therapy remains quite ineffective.Methods:In the...Objective:Glioma is a highly invasive tumor,frequently disposed in essential areas of the brain,which makes its surgical excision extremely difficult;meanwhile adjuvant therapy remains quite ineffective.Methods:In the current report,a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma model.This approach,termed"Karanahan",is aimed at the eradication of cancer stem cells(CSCs),which were recently shown to be capable of internalizing fragments of extracellular double-stranded DNA.After being internalized,these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics,and such an interference results either in elimination of CSCs or in the loss of their tumorigenic potency.Implementation of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA preparation.Results:U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient mice.In SCID mice with developed subcutaneous grafts,the treatment resulted in reliable slowing down of tumor growth rate(P<0.05).In the experiment with intracerebral transplantation of U87 cells followed by surgical excision of the developed graft and subsequent therapeutic treatment,the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the control.Conclusions:The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.展开更多
文摘The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.
基金supported by the Russian Ministry of Science and High Education,State Budgeted Project 0259-2021-0013 for the Institute of Cytology and Genetics,Novosibirskthe Russian Foundation for Basic Research(Grant No.18-34-20016)+1 种基金Microscopic examination of bone marrow cells was supported by the Russian Ministry of Science and High EducationState Budgeted Project 0246-2021-0017 for the Institute of Molecular and Cellular Biology,Novosibirsk。
文摘Objective:Glioma is a highly invasive tumor,frequently disposed in essential areas of the brain,which makes its surgical excision extremely difficult;meanwhile adjuvant therapy remains quite ineffective.Methods:In the current report,a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma model.This approach,termed"Karanahan",is aimed at the eradication of cancer stem cells(CSCs),which were recently shown to be capable of internalizing fragments of extracellular double-stranded DNA.After being internalized,these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics,and such an interference results either in elimination of CSCs or in the loss of their tumorigenic potency.Implementation of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA preparation.Results:U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient mice.In SCID mice with developed subcutaneous grafts,the treatment resulted in reliable slowing down of tumor growth rate(P<0.05).In the experiment with intracerebral transplantation of U87 cells followed by surgical excision of the developed graft and subsequent therapeutic treatment,the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the control.Conclusions:The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.
