A Study in vitro on the Synergetic Cytocidal Effect ofAscorbic Acid and Mitomycin C against the Ehrlich As-cites Tumor Cells in Culture

The synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich as-cites tumor cells in culture was studied. The chain scission of DNA by Cu(Ⅱ)mitomycin C/ascorbic acid system,and the chemical kinetics of the Cu(Ⅱ) catalyzed aerobic oxidation of ascorbic acid in the presence of mitomycin C were also discussed. Experimental results showed that ascorbic acid and mitomycin C were synergetic in destroying Ehrlich ascites tumor cells.The effect is related to the breaking action of the Cu(Ⅱ)mitomycin C/ascorbic acid system on the DNA chain, and to the quantity of the system produced ·OH, and the speed of production which are both directly proportional to the concentration of ascorbic aci.These results imply that the ·OH produced in the aerobic oxidation of ascorbic acid,and·OH induced scission of DNA chain, are important factors to he synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich ascites tumor cells.

COMPARATIVE STUDY OF PHOSPHOTYROSYL PROTEIN PHOSPHATASE OF MICE NORMAL LIVER, REGENERATING LIVER, AND MICE H22A HEPATOMA ASCITES CELL

In regenerating liver of mice, marked increase of the activity of phosphotyrosyl protein phosphatase (PTPP) in cytosol was observed. The PTPP activity varied with time and reached the highest level between 24 to 48 hours after partial hepatectomy. In H22a cells the PTPP activity found in every subcellular fraction was lower than that of the normal liver. The PTPP activity was mostly concentrated in lysosomes of normal liver, but mainly distributed in nucleus, cytosol and microsome of regenerating liver. In H22a cells PTPP activity seemed distribute evenly. Five similar major PTPP peaks (I-V) were obtained on DEAE cellulose chromatography of cytosols from all three of liver cells studied. However, two additional PTPP peaks, a and b, were also obtained from cytosol of liver.

THE SENSITIVITY OF EHRLICH ASCITIC CARCINOMA CELLS TO THE EMPERIPOLESIS OF THYMUS LYMPHOCYTES

In mixed lymphocyte-tumor all culture in vitro, the ability of thymus lymphocytes adhering to tumor cells was found to be essentially consistent with its emperipolesis index, though not synchronous. Tumor cells at different progressive stages and in the mixed cultures with or without Con A stimulation also varied in the sensitivity to lymphocyte adhesion and emperipolesis. Tumor adhesiveness anl emperipolesis of theymus lymphocytes and their PNA-, PNA+ subgroups were shown to be different significantly from splenic lymphocytes. Thymosin exhibited certain promotive effect on lymphocyte-tumor adhesion and emperipolesis.

ESTABLISHMENT OF A MURINE ASCITES HEPATOMA CELL LINE H_(22)-F_(25)/L AND ITS BIOLOGICAL CHARACTERISTICS

Having been passed for 160 generations, a cell linedesignated as H22-F25/L was established from a murine tumorlymphatic metastatlc model H22-F25 which had been set up in our college. The cell line was in suspension culture with a rapid proliferation and stable growth. The peak tune of cell division and proliferation was 48 and 96 hours after culture. In a week, the cell number was Increased by 25 tunes. H22-F25/L still keeps the features of a poorly differentiated cancer. Its tumor inducing rate (in vivo)was 100% in 615 mice. Lymph node metastasis rate was 50% and pulmonary metastasis rate 10%. H22- F25/ L Is a population of heterogenetlc tumor cells Including 2 stem cell lines (the model number of chromosomes being 43 in 40% tumor cells and 86 in 32%) and some side lines. The common marker chromosomes M1, M2, M3 and M4 were present in all stem and side lines.

Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential (Hca-P/L_(6))

In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells,a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential(Hca-P/L_(6))was established and the effect of curcumin on biological behavior of Hca-P/L_(6) was observed.Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential(Hca-P)was subcutaneously inoculated into the medioventral line of a mouse 615 and thefirst generation of metastatic tumor cells of inguinal lymph node(Hca-P/L_(1))was obtained.Then,Hca-P/L_(1) was screened by the route of mouse foot pad subcutaneously!lymph node!scale-up culture in vitro!mouse foot pad subcuta-neously forfive times consecutively.The sensitivity of two murine ascites hepatocarcinoma cell lines(Hca-P and Hca-P/L_(6))and two anchorage-dependent human hepato-carcinoma cell lines(SMC7721 and HepG_(2))to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay after these cells had been pretreated by curcumin at the concentration of 15–240μmol/L for 48 h.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15μmol/L in vitro,the effect of curcumin against cell proliferation of Hca-P and Hca-P/L6 was observed by inverted micro-scope,cell growth curve and cell population doubling time;the effects of curcumin on cell cycles of Hca-P/L6 and Hca-P were studied byflow cytometry(FCM).The results showed Hca-P/L_(6) spreading to the lymph nodes at multiple sites in mice was screened from Hca-P.The lymph node metastatic rate was 100%.Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner(P<0.05).At concentrations of 30–120μmol/L,curcu-min had more inhibition on murine ascites hepatocarci-noma cell lines than on human anchorage-dependent hepatocarcinoma cell lines.At concentrations of 60–240μmol/L,curcumin had more inhibition on Hca-P/L_(6) with the 50%inhibitory concentration(IC50)of 51.48μmol/L than on Hca-P with IC50 of 90.87μmol/L.After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days,the proliferations of Hca-P/L_(6) and Hca-P were inhibited(P<0.05)in a time-dependent manner(P<0.01)and the population doubling time of Hca-P/L6 and Hca-P was prolonged(P<0.01),and curcumin had more inhibition on Hca-P/L6 than on Hca-P(P<0.05).After pretreatment by 15μmol/L curcumin for 48 h,the morphous of Hca-P/L_(6) was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L6 being blocked in the S phase and Hca-P in the S and G_(2)/M phases.Hca-P/L_(6) was validated to be more sensitive to curcumin than Hca-P.Hca-P/L_(6) is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.

In vitro cytotoxic studies of red algae Portieria hornemannii and Spyridia fusiformis against Dalton’s lymphoma ascite and Ehrlich ascite carcinoma cell lines

Objective:To study the in vitro cytotoxic activities of methanol extract of Portieria hornemannii(P.hornemannii)and Spyridia fusiformis(S.fusiformis)using Dalton’s lymphoma ascite and Ehrlich ascite carcinoma cell lines.Methods:The effect of cytotoxicity of P.hornemannii and S.fusiformis was evaluated with the concentrations(100 to 200μg/mL)and assessed for the antitumour activity vs.the selected cell lines using Trypan blue assay.Results:The methanol extracts of P.hornemannii and S.fusiformis showed potent cytotoxic activity with IC_(50)values of(209.00±0.05)μg/mL and(190.00±0.05)μg/mL against the Dalton’s lymphoma ascite cell line and IC_(50)values of(190.00±0.05)μg/mL and(182.00±0.05)μg/mL against the Ehrlich ascite carcinoma cell line respectively.In vitro cytotoxicity against the tested cancer cell lines showed strong activity by the abnormal activities of algal residue in the normal cells.Conclusions:The methanol solvent residue of red algae(P.hornemannii and S.fusiformis)could be a good candidate.It would be a novel marine resource as a antitumor medicine demonstrated by cytotoxic studies that the above marine algae can be a potential candidate sources as antitumor drugs.

In vivo anticancer activity of vanillin,benzophenone and acetophenone thiosemicarbazones on Swiss albino mice

Objective:To study the anticancer activities of three schiff bases viz.vanillin thiosemicarbazone,benzophenone thiosemicarbazone and acetophenone thiosemicarbazone against Ehrlich ascites carcinoma(EAC)cells in Swiss albino mice.Methods:Synthesized compounds have administrated into the intraperitoneal cavity of the EAC inoculated mice at two doses.The anticancer activities have studied by monitoring the parameters such as cell growth inhibition,tumor weight measurement,survival time of EAC bearing mice as well as the changes in depleted hematological parameters due to tumorgenesis.All such data have been compared with those of a known standard drug bleomycin at the dose of 0.3 mg/kg(i.p.).Results:It has been found that these bases enhanced life span,reduced average tumor weight and inhibited tumor cell growth of EAC cell bearing mice remarkably.The results were similar in potency to those obtained with bleomycin.It was also found that the depleted hematological parameters(red blood count,white blood count and haemoglobin content)were found to be restored gradually towards normal within few weeks after ceasing the treatment.Conclusions:The compounds can be primarily considered more or less as potent anticancer agents.