Modulation of cytotoxicity of cytostatic drugs by hemodialysis in vitro and in vivo

For most cytotoxic substances there are no established guidelines on how to deal with overdosage. Little is known about the dialysability of cytostatic drugs. To obtain further information, human plasma was incubated with cytostatic drugs and dialysed in vitro, using 'minimodules' with capillaries identical to those in clinical use. Cytotoxicity before and after dialysis was measured in a biological test system using permanent human lymphoblast cultures (LS2). The 20 cytostatic drugs studied were categorized as follows: (1) Dialysability in vitro. Good: methotrexate (MTX), 5-fluorouracil (5-FU/5-FUdR), cytarabine (ARAC), actinomycin D (DACT), mitomycin C (MMC), 4-OH-cyclophosphamide (4-OH-CPM), ifosfamide (IFO), melphalan (L-PAM), dacarbazine (DTIC), cisplatin (DDP). Intermediate: Adriamycin (ADM), 4'-epi-doxorubicin (4'-EA), carmustine (BCNU). Ineffective: daunorubicin (DNR), vincristine (VCR), vinblastine (VBL), vindesine (VDS), etoposide (VP-16), teniposide (VM-26), mitoxantrone (MITOX). These in vitro results cannot be transferred automatically into the in vivo situation because of specific drug distribution and metabolic rates. Considering pharmacokinetic data from the literature, the following recommendations can be made for practical clinical purposes. (2) Detoxification by hemodialysis in vivo. Possibly effective: MTX, 5-FU, MMC, CPM, IFO, L-PAM, BCNU, DTIC. Ineffective: ADM, 4'-EA, DNR, MITOX, DACT, VP-16, VM-26, VCR, VBL, VDS, ARAC, DDP.     

二十二碳六烯酸复合物的体内外抑瘤作用及其机制

目的 探讨二十二碳六烯酸(DHA)复合物的抗癌作用及其作用机制.方法 建立H22小鼠肝癌细胞的移植瘤动物模型,观察DHA复合物的体内抑瘤作用,采用体外细胞培养的方法 ,观察DHA复合物对宫颈癌HeLa细胞和胶质瘤U251细胞的体外抑瘤作用.采用电镜和荧光显微镜观察细胞形态的变化.Western blot法测定移植瘤组织中caspase-3蛋白的表达,逆转录聚合酶链反应(RT-PCR)检测HeLa细胞和U251细胞中Bel-2和Bax mRNA的表达.结果 DHA复合物对小鼠H22细胞移植瘤有明显的抑瘤作用,其低、中、高剂量组的抑瘤率分别为37.62%、48.55%和58.63%.在体外,随着剂量的增加,DHA复合物对HeLa细胞和U251的生长抑制率逐渐增高,Hela细胞的IC50为0.9814 μg/ml,U251细胞的IC50为0.3746 μg/ml.DHA复合物处理后,移植瘤细胞的细胞核呈分叶状,可见大小不等、致密的凋亡小体;HeLa细胞的细胞核内可见致密浓染的黄绿色荧光和碎片,分布在核周边,呈肾形或者半月形,核固缩,趋于碎裂.与CMC组比较,DHA复合物能明显促进caspase-3蛋白的表达,且DHA复合物剂最越高,caspase-3蛋白的表达升高越明显.DHA复合物能下调U251细胞中Bcl-2 mRNA的表达,上调Bax mRNA的表达,与CMC组比较,差异均有统计学意义(均P<0.01).结论 DHA复合物在体内外对多种肿瘤细胞有抑制作用,其抑瘤作用可能是通过抑制Bcl-2的表达、促进Bax和caspase-3的表达实现的.     

二十二碳六烯酸复合物的体内外抑瘤作用及其机制

目的 探讨二十二碳六烯酸(DHA)复合物的抗癌作用及其作用机制.方法 建立H22小鼠肝癌细胞的移植瘤动物模型,观察DHA复合物的体内抑瘤作用,采用体外细胞培养的方法 ,观察DHA复合物对宫颈癌HeLa细胞和胶质瘤U251细胞的体外抑瘤作用.采用电镜和荧光显微镜观察细胞形态的变化.Western blot法测定移植瘤组织中caspase-3蛋白的表达,逆转录聚合酶链反应(RT-PCR)检测HeLa细胞和U251细胞中Bel-2和Bax mRNA的表达.结果 DHA复合物对小鼠H22细胞移植瘤有明显的抑瘤作用,其低、中、高剂量组的抑瘤率分别为37.62%、48.55%和58.63%.在体外,随着剂量的增加,DHA复合物对HeLa细胞和U251的生长抑制率逐渐增高,Hela细胞的IC50为0.9814 μg/ml,U251细胞的IC50为0.3746 μg/ml.DHA复合物处理后,移植瘤细胞的细胞核呈分叶状,可见大小不等、致密的凋亡小体;HeLa细胞的细胞核内可见致密浓染的黄绿色荧光和碎片,分布在核周边,呈肾形或者半月形,核固缩,趋于碎裂.与CMC组比较,DHA复合物能明显促进caspase-3蛋白的表达,且DHA复合物剂最越高,caspase-3蛋白的表达升高越明显.DHA复合物能下调U251细胞中Bcl-2 mRNA的表达,上调Bax mRNA的表达,与CMC组比较,差异均有统计学意义(均P<0.01).结论 DHA复合物在体内外对多种肿瘤细胞有抑制作用,其抑瘤作用可能是通过抑制Bcl-2的表达、促进Bax和caspase-3的表达实现的.     

二十二碳六烯酸复合物的体内外抑瘤作用及其机制

目的 探讨二十二碳六烯酸(DHA)复合物的抗癌作用及其作用机制.方法 建立H22小鼠肝癌细胞的移植瘤动物模型,观察DHA复合物的体内抑瘤作用,采用体外细胞培养的方法 ,观察DHA复合物对宫颈癌HeLa细胞和胶质瘤U251细胞的体外抑瘤作用.采用电镜和荧光显微镜观察细胞形态的变化.Western blot法测定移植瘤组织中caspase-3蛋白的表达,逆转录聚合酶链反应(RT-PCR)检测HeLa细胞和U251细胞中Bel-2和Bax mRNA的表达.结果 DHA复合物对小鼠H22细胞移植瘤有明显的抑瘤作用,其低、中、高剂量组的抑瘤率分别为37.62%、48.55%和58.63%.在体外,随着剂量的增加,DHA复合物对HeLa细胞和U251的生长抑制率逐渐增高,Hela细胞的IC50为0.9814 μg/ml,U251细胞的IC50为0.3746 μg/ml.DHA复合物处理后,移植瘤细胞的细胞核呈分叶状,可见大小不等、致密的凋亡小体;HeLa细胞的细胞核内可见致密浓染的黄绿色荧光和碎片,分布在核周边,呈肾形或者半月形,核固缩,趋于碎裂.与CMC组比较,DHA复合物能明显促进caspase-3蛋白的表达,且DHA复合物剂最越高,caspase-3蛋白的表达升高越明显.DHA复合物能下调U251细胞中Bcl-2 mRNA的表达,上调Bax mRNA的表达,与CMC组比较,差异均有统计学意义(均P<0.01).结论 DHA复合物在体内外对多种肿瘤细胞有抑制作用,其抑瘤作用可能是通过抑制Bcl-2的表达、促进Bax和caspase-3的表达实现的.     

Dialysability of cytostatic drugs. Experimental studies in vitro

There are no established guidelines for detoxification for most cases of overdosage or intoxication with cytostatic drugs. Little is known about the dialysability of cytostatic drugs. To obtain further information on the dialysability of cytostatic drugs, human plasma was incubated with cytostatic drugs and dialysed in vitro using "mini-modules" with capillaries identical to clinical use. Cytotoxicity before and after dialysis was measured in a biological test system using permanent human lymphoblast cultures (LS2). The 20 cytostatic drugs studied could be categorised as follows: Good dialysability in vitro: methotrexate, 5-fluorouracil, cytarabine, actinomycin D, mitomycin C, 4-OH-cyclophosphamide, ifosfamide, melphalan, dacarbazine, cisplatin. Intermediate dialysability in vitro: adriamycin, epirubicin, carmustine. Ineffective dialysability in vitro: daunorubicin, vincristine, vinblastine, vindesine, etoposide, teniposide, mitoxantrone. These in vitro results cannot be transferred automatically into the in vivo situation because of specific drug distribution and metabolic rates. Considering pharmacokinetic data, the following recommendations can be made for practical clinical purposes: Detoxification by hemodialysis in vivo: Possibly effective: Methotrexate, 5-fluorouracil, mytomicin C, cyclophosphamide, ifosfamide, melphalan, carmustine, dacarbazine. Ineffective: Adriamycin, epirubicin, daunorubicin, mitoxantrone, actinomycin D, etoposide, teniposide, vincristine, vinblastine, vindesine, cytarabine, cisplatin.     

Antitumor effect of antiplatelet agents in gastric cancer cells: an in vivo and in vitro study

Background

The antitumor effects of antiplatelet agents in gastric cancer cells are not well known. In this study, the possibility of gastric cancer treatment with an antiplatelet agent, mainly aspirin, was examined both in vivo and in vitro.

Methods

For in vivo experiments, tumor-bearing mice were treated by an antiplatelet antibody or aspirin, and the tumor growth was compared. For in vitro experiments, human gastric cancer cell lines were used to confirm the cancer cell growth and inhibition by reducing the platelet count or using aspirin. We also examined several cytokines by using an ELISA assay and conducted microRNA microarray analysis of MKN-45 tumor cells to determine the influence of platelets or aspirin.

Results

In vivo experiments showed that tumor growth was inhibited by halving the circulating platelet count by using an antiplatelet antibody or peroral daily aspirin. In vitro experiments showed that the proliferation rates of gastric cancer cell lines were increased after coincubation with platelets and that the effect was inhibited by aspirin. Although the expression of interleukin-6, platelet-derived growth factor, transforming growth factor-β, and prostaglandin E2 did not correlate with tumor growth inhibition by aspirin, seven microRNAs showed altered expression in cancer cells in response to coincubation with platelets or addition of aspirin. Cells transfected with mir-4670-5p showed a significant increase in proliferation compared to negative control cells.

Conclusions

Our study showed that platelets increased the proliferation of gastric cancer cells and that this increase was inhibited by antiplatelet antibody or aspirin. Mir-4670-5p may play an important role in these responses.

     

亚甲蓝体内抗肿瘤作用及药理学研究

Methylene blue can inhibit the growth of Ehrlich ascitic tumor, L1210 leukemia and P388 leukemia in mice. The average life span of the treated animals was obviously longer than that of the controls. Methylene blue was superior to 5-Fu in the treatment of L1210 leukemia of mice and two thirds of the mice with P388 leukemia were healthy and survived for more than 60 days after administrated different doses of methylene blue. When adriamycin was given simultaneously with methylene blue to mice, the acute toxic effect of adriamycin was decreased and the survival time prolonged. Methylene blue is a highly ionized and a rapidly eliminated drug which can combine well with tissues at higher concentration maintained for several hours and can easily pass through the blood-brain barrier.     

Antitumor activity of mannan-methotrexate conjugate in vitro and in vivo

Conjugation of anticancer drugs with different carriers has been extensively studied recently as a potential method of obtaining improved drug forms. The conjugation often results in the increase of the therapeutic effect, alteration of a toxicity profile, and/or selective targeting of therapeutic agent to the tissue of interest. We have synthesized mannan-methotrexate conjugate by means of methotrexate anhydride and studied its antitumor properties both in vitro and in vivo in comparison with free methotrexate. Mannan-methotrexate conjugate showed significantly improved antitumor activity compared to free methotrexate in the model of P388 mouse leukemia disseminated in the peritoneal cavity treated with intraperitoneally injected chemotherapy. Conversely, the antitumor effects of free methotrexate and mannan-methotrexate conjugate were comparable when leukemia was implanted subcutaneously and chemotherapy agents were administered intravenously. These results suggest that mannan-methotrexate conjugate should be further investigated as a potential therapeutic agent for intraperitoneally disseminated tumors.     

Toxicity of cytostatic drugs to normal bone marrow cells in vitro

In this study we compared how different concentrations and periods of incubation of anthracyclines, amsacrine, and cytosine arabinoside would affect normal hematopoietic bone marrow cells in terms of interindividual differences in toxicity, the age of the donor, and the proliferative capacity of the bone marrow. Bone marrow was obtained from 36 donors in connection with bone marrow transplantation. After separation the mononuclear cell fraction was incubated with doxorubicin, 4-epidoxorubicin, daunorubicin, idarubicin, aclarubicin, mitroxantrone, amsacrine, and cytosine arabinoside for 1 h, for 3 h, or continuously. The cells were thereafter cultured in soft agar and CFU-GM were counted after 10–12 days. The results showed a large interindividual variation in toxicity for all drugs tested. Daunorubicin, idarubicin, aclarubicin, and mitoxantrone had a pronounced cytotoxic effect after 1 h of incubation. Doxorubicin and 4-epi-doxorubicin showed the greatest cytotoxic effect after 3 h and were also more toxic to normal bone marrow cells from donors over 40 years of age. Ara-C had a low cytotoxic effect after 1 and 3 h of incubation, even at high concentrations, but exerted a pronounced degree of toxicity during continuous incubation. Daunorubicin, idarubicin, and ara-C also showed increased toxicity to cell samples with a low proliferating capacity in the control. The conclusions drawn from these results are that interindividual variation, proliferation capacity, incubation conditions, and the age of the donors are factors of importance in the toxicity of drugs to normal hematopoietic bone marrow cells. Received: 12 January 1997 / Accepted: 24 November 1997     

Antitumor effect of anthocyanin fractions extracted from red soybeans and red beans in vitro and in vivo

Many bioflavonoids extracted from petals of higher plants and from fruit rinds, as well as purified flavonoids, have been reported to have antitumor effects in vitro and in vivo. Bioflavonoids extracted from red soybeans are mostly cyanin conjugated with glucose and rhamnose, whereas bioflavonoids of red beans are cyanin conjugated with rhamnose as revealed by thin-layer chromatogram. Flavonoids extracted from red soybeans were effective in inhibiting the growth of HCT-15 cells in vitro. On the other hand, flavonoids from red beans were not effective, although their hydrolyzed sugar-free forms were growth inhibitory. Sugar-bonded bioflavonoids extracted from both red soybeans and red beans were effective in prolonging the survival of Balb/C mice bearing syngeneic tumor-Meth/A cells, when they were dissolved in drinking water and given at a dose of approximately 500 micrograms/mouse/day.     

Antitumor activity of novel ailanthone derivatives in vitro and in vivo

The antitumor activities of two ailanthone derivatives with 15 beta-acyloxy side chains were investigated. The cytotoxic activity of 11 beta, 20-epoxy-1 beta, 11 alpha, 12 alpha-trihydroxy-15-beta-[E)-3-methyl-2-octenoyl) oxypicras-3,13(21)-diene-2,16-dione (SUN2071) and 11 beta, 20-epoxy-1 beta, 11 alpha, 12 alpha-trihydroxy-15 beta-[E)-2-undecenoyl) oxypicras-3,13(21)-diene-2,16-dione (SUN0237) was close to that of bruceantin and vincristine. SUN2071 was shown to be a potent inhibitor of protein synthesis in L1210 cultured cells. When administered i.p. to i.p. inoculated P388 leukemia mice, daily treatment with SUN2071 and SUN0237 significantly increased the lifespan (increases in lifespan in excess of 100% were achieved). These increases were comparable to those achieved with vincristine. The therapeutic ratio of SUN2071 was also close to that of vincristine. However, the compounds were ineffective when administered as a single injection. Daily i.p. treatment with SUN2071 demonstrated significant tumor growth inhibition in mice inoculated s.c. with colon-38 and moderate activity against i.p. L1210 leukemia and i.p. B16 melanoma. The compounds were ineffective when tested against the Lewis lung carcinoma and colon-26. In a preliminary toxicological study, SUN2071 at a therapeutic dose in daily consecutive i.p. injection produced leucopenia.     

Antitumor effect of parathyroid hormone-related protein neutralizing antibody in human renal cell carcinoma in vitro and in vivo

Functional inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene occurs in 40-80% of human conventional renal cell carcinomas (RCCs). We showed recently that VHL-deficient RCCs expressed large amounts of parathyroid hormone-related protein (PTHrP), and that PTHrP, acting through the PTH1 receptor (PTH1R), plays an essential role in tumor growth. We also showed that PTHrP expression is negatively regulated by the VHL gene products (pVHL). Our goal was to determine whether blocking the PTHrP/PTH1R system might be of therapeutic value against RCC, independent of VHL status and PTHrP expression levels. The antitumor activity of PTHrP neutralizing antibody and of PTH1R antagonist were evaluated in vitro and in vivo in a panel of human RCC lines expressing or not pVHL. PTHrP is upregulated compared with normal tubular cells. In vitro, tumor cell growth and viability was decreased by up to 80% by the antibody in all cell lines. These effects resulted from apoptosis. Exogenously added PTHrP had no effect on cell growth and viability, but reversed the inhibitory effects of the antibody. The growth inhibition was reproduced by a specific PTH1R antagonist in all cell lines. In vivo, the treatment of nude mice bearing the Caki-1 RCC tumor with the PTHrP antibody inhibited tumor growth by 80%, by inducing apoptosis. Proliferation and neovascularization were not affected by the antiserum. Anti-PTHrP treatment induced no side effects as assessed by animal weight and blood chemistries. Current therapeutic strategies are only marginally effective against metastatic RCC, and adverse effects are common. This study provides a rationale for evaluating the blockade of PTHrP signaling as therapy for human RCC in a clinical setting.     

DNA, RNA, and protein content in adult acute myeloid leukemia: effects of cytostatic drugs in vivo

DNA, RNA, and/or protein cellular content were studied by flow cytometry in 52 cases of acute myeloid leukemia before and on day 4 of remission induction treatment. Bone marrow (BM) samples were stained after fixation by acridine orange for DNA and RNA content (37 cases) and by propidium iodide and fluorescein isothiocyanate for DNA and protein content (52 cases). A positive correlation was found between pretreatment protein content and BM blast involvement: the higher the percentage of blasts in BM smears the higher the mean protein content (p less than 0.05). Protein content was higher in monoblastic leukemia (M4 and M5) than in the granulocytic types (M1, M2, M3) (p less than 0.05). S + G2 + M was higher in patients with protein content below 80 arbitrary units than in the subgroup with protein content above this threshold (p less than 0.05). Pretreatment RNA content, estimated by the RNase-sensitive fraction of G1 cells, was significantly higher in undifferentiated and M1 leukemias than in the other cytological groups (p less than 0.0001). This fraction was higher in patients who subsequently achieved complete remission, but it was not related to BM blast involvement or proliferative fraction of cells. During cytostatic treatment the changes in RNA and protein content did not follow a typical pattern. The connections between variations of DNA, RNA, and protein content and prognosis are examined and their possible relation to drug-induced blast cell maturation is discussed.     

Antitumor effect of the mTOR inhibitor everolimus in combination with trastuzumab on human breast cancer stem cells in vitro and in vivo

This study evaluated the effects of a mammalian target of mTOR inhibitor everolimus alone or in combination with trastuzumab on stem cells from HER2-overexpressing primary breast cancer cells and the BT474 breast cancer cell line in vitro and in vivo. For the in vitro studies, we sorted ESA(+)CD44(+)CD24(-/low) cells as stem cells from primary breast cancer cells and BT474 cells using flow cytometry. The MTT assay was used to quantify the inhibitory effect of the drugs on total cells and stem cells specifically. Stem cell apoptosis, cell cycle distributions, and their tumorigenicity after treatment were investigated by flow cytometry or soft agar colony formation assays. For the in vivo studies, BALB/c mice were injected with BT474 stem cells, and the different treatments were administered. After necropsy, the expression of Ki67, CD31, AKT1, and phospho-AKT (Thr308) was analyzed by immunohistochemistry. For the in vitro studies, Treatment with everolimus resulted in stem cell growth inhibition in a dose-dependent manner. The combination of everolimus with trastuzumab was more effective at inhibiting cell growth (P?相似文献   

In vitro and In vivo Antitumor Activity of Tiliacorinine in Human Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a fatal cancer with poor prognosis and less than 10% of CCA patients can be offered surgical cure. Conventional chemotherapy results in unfavorable outcomes. At present, plant-derived compounds are gaining interest as potential cancer therapeutics, particularly for treatment-refractory cancers. In this study, antitumor activity of tiliacorinine, the major alkaloid isolated from a tropical plant, on CCA was first demonstrated. Antiproliferative effects of tiliacorinine on human CCA cell lines were investigated using SRB assays. Acridine orange/ethidium bromide staining, flow cytometric analysis and DNA laddering assays were used for apoptotic determination. Apoptosis-related proteins were verified by Western blotting and antitumor activity of tiliacorinine in vivo was demonstrated in CCA xenografted mice. Tiliacorinine significantly inhibited proliferation of human CCA cell lines with IC50 4.5-7 μM by inducing apoptosis through caspase activation, upregulation of BAX, and down-regulation of BclxL and XIAP. Tiliacorinine considerably reduced tumor growth in CCA xenografted mice. These results demonstrated antitumor effects of tiliacorinine on human CCA in vitro and in vivo. Tiliacorinine may be an effective agent for CCA treatment.     

The FLT3 inhibitor PKC412 in combination with cytostatic drugs in vitro in acute myeloid leukemia

An internal tandem duplication of FLT3 (FLT3/ITD) occurs in approximately 25% of newly diagnosed AML. PKC412 inhibits the growth of leukemic cell lines with FLT3 mutations such as the MV4-11. This study evaluated the in vitro effects of the combination of PKC412 and ara-C or daunorubicin, studying the effect of co-incubation, pre-incubation and sequential incubation of the drugs in patient samples and cell lines. Thirty-three patients with AML were included. Two cell lines were studied; MV4-11 that expresses the FLT3/ITD and HL-60 that does not. In the patient cells PKC412 exerted its effect at concentrations between 0.1 and 2.0 microM. For MV4-11 cells concentrations down to 1 nM were effective. In patient samples, the results of co-incubation of PKC412 with ara-C were synergistic in 5%, additive in 67%, sub additive in 17% and antagonistic in 11% of the cases. In patient cells, incubations with ara-C and PKC412 resulted in synergistic effects in 17% of the FLT3/ITD positive samples compared to 0% synergistic in the FLT3/ITD negative samples (p < 0.01). Antagonistic effects were more common in the FLT3/ITD negative samples. The timing of the drugs had little impact on the effect. In cell lines, antagonistic effects were seen frequently in HL-60 (90%) and less so in MV4-11 (60%) regardless of sequence or timing of the drugs. The combination of daunorubicin and PKC412 resulted in more synergistic and less antagonistic effects compared to combinations with ara-C, in both patient material and cell lines. The combination of Lonafarnib, a farnesyl-transferase inhibitor (FTI) and PKC412 had additive and synergistic effects in both FLT3/ITD positive and negative cell lines. In conclusion, the combination of PKC412 together with chemotherapeutic drugs is more effective in FLT3/ITD positive AML cells. Antagonistic effects can be seen, especially in patient samples without FLT3/ITD. Also, the combination of PKC412 and the farnesylinhibitor lonafarnib should be further explored.     

Combination effects of etoposide with other antitumor drugs in vitro and in vivo

Combination effects of etoposide (ET) with each of 10 antitumor drugs were examined with P 388 leukemia cells in vitro and in vivo. Median effect analysis was applied for the evaluation of in vitro effect by the growth inhibition, and the in vivo effect by comparison of the increase of life span (ILS) in a combined group with the sum of ILS's in 2 single agent groups. Among 10 drugs combined with ET, cyclophosphamide (melphalan was used for in vitro study), cisplatin and 6-mercaptopurine exhibited a strong synergism both in vitro and in vivo. The combination of ET with mitomycin C, vincristine, vindesine or cytarabine produced additive or slightly synergistic effect in the both systems. However, methotrexate + ET combination showed an antagonistic effect. Although the combination of ET with doxorubicin or fluorouracil showed a slight synergism in vitro, it was antagonistic in vivo. Thus, the in vitro and in vivo combined effects were consistent in 8 of 10 drugs. The employed methods in the present studies could distinguish high efficacy of ET + cyclophosphamide and ET + cisplatin, which are clinically approved as effective combinations against lung cancer. The methods seem to be useful to assess the drug efficacy in experimental combination.     

Antitumor effect of JM-8 (a cisplatin analogue) on testicular cancer cells in vitro and in vivo

Using transplantable testicular tumor lines serially passaged in nude mice, the antitumor effect of JM-8, an analogue compound of cisplatin, was evaluated by clonogenic assay and in nude mice. JM-8 exhibited compatible tumor growth inhibition to that of 8 to 10 times the concentration of cisplatin both in vitro and in vivo. In addition, JM-8 had less toxicity than cisplatin in vivo. However, when JM-8 was adopted for treatment of regrowing tumors after repeated manipulations with cisplatin, it exerted less growth inhibition than cisplatin. Apart from this effect, it was considered that JM-8 could be substituted for cisplatin in clinical use.     

转染4-1BBL基因的胃癌细胞在小鼠体内的抗肿瘤及免疫调节作用

目的:观察转染4-1BBL基因的小鼠胃癌细胞株MFC的体内致瘤性及其对小鼠免疫功能的影响。方法:通过脂质体介导以重组质粒pMKITneo和pMKITneo/4-1BBL转染小鼠胃癌细胞株MFC。用RT-PCR法检测目的基因的表达。计数法绘制体外培养细胞生长曲线。将转染前后肿瘤细胞,分别接种于615小鼠背部皮下观察其致瘤性。流式细胞仪测定荷瘤小鼠外周血NK、CD4 T和CD8 T细胞数,并测定荷瘤小鼠肿瘤结节内细胞凋亡率。结果:MFC/4-1BBL细胞中可检测到4-1BBLmRNA表达。转染前后肿瘤细胞的体外生长速度无明显变化。MFC/4-1BBL细胞在小鼠体内的致瘤性较MFC/pMKITneo细胞和野生型MFC细胞明显降低。接种MFC/4-1BBL细胞的小鼠外周血NK细胞及CD8 T细胞数明显增多;其肿瘤结节内细胞凋亡率亦明显增高。结论:转染4-1BBL基因后并未影响MFC细胞的体外生长,但其在小鼠体内的致瘤性明显降低。MFC/4-1BBL细胞可诱导荷瘤小鼠体内CD8 T和NK细胞增殖,而且能促进肿瘤细胞的凋亡。