Potentiated antitumor effects of a combination therapy with a farnesyltransferase inhibitor L-744,832 and butyrate in vitro

Farnesyltransferase inhibitors, butyrate and butyric acid derivatives have previously been reported to exert anti-tumor activity in experimental models in vitro and in vivo and have recently gained acceptance as potential anticancer agents. In our study, we examined antitumor effects of a combination of a farnesyltransferase inhibitor L-744,832 and butyrate in vitro against MDA-MB-231 and MIA PaCa-2 human cancer cells. This combination therapy showed synergistic antitumor activity against MDA-MB-231 cells, which was at least in part due to induction of p27KIP1 expression. Both drugs increased intracellular levels of p53 as well but there was no significant difference between the groups treated with single drugs and the group treated with their combination. In MIA PaCa-2 cells, the combination therapy exerted additive antitumor activity. Our results illustrate possible application of the farnesyltransferase inhibitor L-744,832 and butyrate as a combination therapy of cancer.     

Potentiating antitumor effects of a combination therapy with lovastatin and butyrate in the Lewis lung carcinoma model in mice

Lovastatin, the drug used for the treatment of hypercholesterolemia, has previously been reported to exert antitumor activity in experimental murine models. Butyrate and butyric acid derivatives are well known to induce differentiation and apoptosis of tumour cells and also have recently gained acceptance as potential anticancer agents. In this study, we examined the antitumor effects of the combination of lovastatin and butyrate or its prodrug tributyrin in vitro and in vivo against a murine Lewis lung carcinoma (3LL). This combination therapy showed synergistic antitumor activity against 3LL cells in vitro. These effects were at least in part due to apoptosis induction that occurred after 12 hr of incubation with lovastatin and butyrate and was preceded by changes in cell cycle distribution of treated cells and expression of p21, p53 and cyclin D1. Remarkably, a systemic treatment of syngeneic mice inoculated with 3LL cells with both drugs resulted in significant tumour growth retardation.     

Potent antitumor effects of a novel actinomycin D analog Leu5AMD

Leu5AMD ([D-Val2, L-MeLeu5]2 AMD) is a novel actinomycin D (AMD) analog, in which both N-methylvalines were replaced by N-methylleucines. In the present study, an attempt has been made to investigate the effects of Leu5AMD on the proliferation of human gastric carcinoma cell line SGC-7901. The results showed that Leu5AMD inhibited the proliferation and induces apoptosis in SGC-7901 cells in a dose-dependent manner. Apoptosis induced by Leu5AMD was further confirmed by annexin V-FITC/PI dual staining assay. After treatment with Leu5AMD, the loss of mitochondrial potential and the decrease of bcl-2 gene expression were observed in apoptotic cells, suggesting that Leu5AMD may be involved in mitochondria and bcl-2 related apoptotic pathway. In addition, the in vivo antitumor effects of Leu5AMD on S-180 bearing mice and the acute toxicity on healthy mice were investigated. Treatment with Leu5AMD markedly suppressed the growth of Sarcoma xenograft. These results suggest that Leu5AMD may be used as a promising chemotherapeutical agent for patients affected by gastric carcinoma and other solid cancer.     

Immunohistochemical localization of actinomycin D in human melanoma tumor cells

Human melanoma tumor colonies and derived cell lines (81-46a) were exposed to Actinomycin D (Act D) in vitro in order to study subcellular sites of drug-cell interaction. Light microscopy of 13 day-old colonies previously treated for 24 hours with 0.01 microgram/ml, 0.1 microgram/ml, and 1 microgram/ml Act D revealed a decrease in colony size and organization, an increase in pyknotic nuclei, and an accumulation of cell debris concomitant with an increase in Act D concentration. The 81-46a cells were treated with 0.1 microgram/ml Act D for 15, 30, and 60 minute intervals, followed by Act D antibodies. Immunofluorescence microscopy revealed both cytoplasmic, vesicular, filamentous, and nuclear variations in drug distribution with increased exposure. Cell viability studies indicated a decrease in viable cells as exposure time to Act D increased.     

Potentiated antitumor effects of the combination treatment with statins and pamidronate in vitro and in vivo

The aim of the present study was to examine the potential antitumor activity of lovastatin and other statins together with pamidronate, a second generation bisphosphonate (BP), against tumor cell lines. Cytostatic/cytotoxic effects were measured using crystal violet assay. Regulation of the cell cycle and induction of apoptosis were evaluated using flow cytometry and Western blotting, migration of tumor cells was measured in a scratch wound assay and their invasiveness was measured with a Matrigel-invasion assay. Antitumor effects of the combination treatment were evaluated in a murine PANC 02 pancreatic adenocarcinoma model. Combination of pamidronate and lovastatin produced potentiated cytostatic/cytotoxic effects against breast and pancreatic cancer cell lines. The combination was also effective in inhibition of tumor cell adhesion to collagen IV and fibronectin and interfered with migration and invasiveness of tumor cells. Neither pamidronate nor lovastatin alone affected tumor growth in mice but the combination treatment resulted in retardation of tumor growth and prolongation of mouse survival. The combination of statins and pamidronate, a second generation bisphosphonate, demonstrates promising antitumor effects at doses readily achievable in patients. This combination holds promise for future clinical studies.     

Disposition of [3H]actinomycin D in tumor-bearing mice.

A single, nonlethal dose of actinomycin D will cause total regression and cure of Ridgway osteogenic sarcoma in mice. A cure is not obtained with a single dose daily for 7 days, a dose regimen which kills 10% of normal C57BL/6 X DBA/2 mice. This suggests that actinomycin D is more effective on a single high-dose schedule than on chronic daily therapy. Analysis of drug exposure in Ridgway osteogenic sarcoma and normal mouse tissues following the single and multiple-dose regimens suggests the difference in therapeutic response is due to drug exposure at a higher concentration in Ridgway osteogenic sarcoma after the single high dose than after the multiple-dose regimen. This may be related to the higher drug concentration attained in blood following the single-dose regimen than is attained with the multidose regimen.     

Enhancement of interferon antitumor action by sodium butyrate.

Sodium butyrate together with interferon enhances the antitumor effect of interferon in vivo. When Sarcoma 180 TG cells are inoculated in mice, the mean survival time and final survival rate are greatly increased compared to those for treatment with interferon alone. Similarly, a significant delay in the mean survival time is observed when mice inoculated with L1210 cells are treated with sodium butyrate and interferon. This effect could be due at least in part to a potentiation of interferon action on the tumor cells.     

Efficacy of repeat isolated limb infusion with melphalan and actinomycin D for recurrent melanoma

BACKGROUND:

Isolated limb infusion (ILI) is an effective and minimally invasive treatment option for delivering regional chemotherapy in patients with metastatic melanoma confined to a limb. Recurrent or progressive disease after an ILI, however, presents a challenge for further treatment. The value of repeat ILI in this situation has not been well documented.

METHODS:

Forty‐eight patients were identified who had been treated with a repeat ILI. In all patients, a cytotoxic combination of melphalan and actinomycin D was used.

RESULTS:

The median time between the 2 procedures was 11 months. The complete response (CR) rate after repeat ILI was 23%, compared with 31% after the initial ILI (P = .36). The overall response was 83%, compared with 75% after the first procedure (P = .32). The median duration of response was 11 months (10 months for patients with CR; P = .80), and median survival was 38 months. In those patients achieving a CR, the median survival was 68 months (P = .003). Toxicity after repeat ILI was increased, with 20 patients experiencing Wieberdink grade III limb toxicity (considerable erythema and edema with blistering) and 5 patients experiencing grade IV toxicity (threatened or actual compartment syndrome), whereas after the initial ILI these toxicity grades occurred in 14 patients and 1 patient, respectively (P = .03). No patient experienced grade V toxicity (requiring amputation).

CONCLUSIONS:

Repeat ILI is an attractive treatment option to achieve limb salvage in patients with inoperable recurrent or progressive melanoma after a previous ILI. It can be associated with significant short‐term regional toxicity, but is well tolerated by most patients, with satisfactory response rates. Cancer 2009. © 2009 American Cancer Society.     

Phase II study of bleomycin,actinomycin D,DTIC and vindesine in disseminated malignant melanoma

Twenty-seven patients with disseminated malignant melanoma were treated with combination chemotherapy consisting of bleomycin, actinomycin D, DTIC and vindesine. There were 4 complete responses in patients with pulmonary metastasis, 5 patients had a partial remission, 2 of them had mainly lung lesions. Toxicity consisted mainly of leuco- and thrombocytopenia of short duration and sporadic severe mucositis.     

Enhancement by stable butyrate derivatives of antitumor and antiviral actions of interferon.

The use of n-butyric acid has been associated with induction of cell differentiation and bypassing of genetic defects in the suppression of malignancy. This biological response modifier satisfies the requirements for specificity and low toxicity, and its use can be considered as an alternative approach to conventional cancer chemotherapy. However, a lack of clinical efficacy has been observed with butyrate and attributed mainly to the rapid metabolism of the compound. Butyric acid pro-drugs derived from monosaccharides such as 3-O-butanoyl-1,2-O-isopropylidene-alpha-D-glucofuranose (MAG = 3but) have consequently been devised. Pharmacokinetic and biological advantages of MAG = 3but have been previously described. In the present report, we have studied the effect of MAG = 3but on murine interferon-alpha, beta (IFN) anticellular, antitumor and antiviral activities. In vitro, it appears that MAG = 3but predisposes malignant MSV cells to a later, complete establishment of the antiproliferative and the cell-differentiating effects of IFN, and the antiviral action of the latter in the same line of cells infected with encephalomyocarditis (EMC) virus. In vivo, combined treatment with MAG = 3but and IFN protects mice effectively against the fatal development of ascitic sarcoma 180 TG and the lethal effect of EMC virus infection.     

Studies of actinomycin D induced B23-translocation in P388D1 cells implanted in DBA/2 mice.

Nucleophosmin/B23 is a nucleolar phosphoprotein which redistributes from nucleoli to nucleoplasm (B23-translocation) when cells are exposed to certain anticancer drugs, particularly intercalators. The B23-translocation assay has been demonstrated in cell culture to correlate with drug effects and to detect drug-resistant cells. We now report the effect of actinomycin D on B23-translocation in P388D1 cells implanted in DBA/2 mice. B23-translocation was observed in cells after actinomycin D treatment in a dosage- and time-dependent manner. Translocation could be observed within 30 min after drug treatment. Complete B23-translocation with at least 1-day duration was achieved by a single injection of 0.25 mg/kg. Reduced dosages produced partial B23-translocation with shorter durations. These results indicate that B23-translocation may be useful in monitoring drug effects in animals.     

肝脂素对小鼠S37肉瘤与B16黑色素瘤的抗肿瘤作用

目的：探讨肝脂素（Heplipin)对S37和B16两种肿瘤细胞移植瘤的生长抑制作用。方法：小鼠S37肉瘤和B16黑色素瘤移植瘤在高、中、低剂量（每天分别为3000、1800、1100mg/kg)肝脂素胃饲为治疗组,环磷酰胺（CTX）20mg(kg／天）和生理盐水作为两对照组。比较抑瘤率、癌周边部血管数、总肿瘤面积中坏死区所占比例,结果：肝脂素对S37肉瘤和B16黑色素瘤的抑瘤分别为大剂量：75．1％和47．0％、中剂量：69．7％和32．1％、小剂量：61．7％和13．0％,显示出明显的剂量效关系,与生理盐水对照组相比有显著性差异。在S37肉瘤荷瘤小鼠的实验中,组织学观察发现,肝脂素用药组肿瘤周边部单痊面积血血管数明显少于阴性对照组和CTX组;肝脂素治疗组的肿瘤坏死面积明显大于对照组,结论：肝脂素可明显抑制小鼠S37肉瘤和B16黑色素瘤的生长,其抗肿瘤机制可能与抑制肿瘤生长血管的生成,导肿瘤缺血坏死有关。     

Cooperative antitumor effects of vitamin D3 derivatives and rosemary preparations in a mouse model of myeloid leukemia

1alpha,25-dihydroxyvitamin D(3) (1,25D(3)) is a powerful differentiation agent, which has potential for treatment of myeloid leukemias and other types of cancer, but the calcemia produced by pharmacologically active doses precludes the use of this agent in the clinic. We have shown that carnosic acid, the major rosemary polyphenol, enhances the differentiating and antiproliferative effects of low concentrations of 1,25D(3) in human myeloid leukemia cell lines (HL60, U937). Here we translated these findings to in vivo conditions using a syngeneic mouse leukemia tumor model. To this end, we first demonstrated that as in HL60 cells, differentiation of WEHI-3B D(-) murine myelomonocytic leukemia cells induced by 1 nM 1,25D(3) or its low-calcemic analog, 1,25-dihydroxy-16-ene-5,6-trans-cholecalciferol (Ro25-4020), can be synergistically potentiated by carnosic acid (10 microM) or the carnosic acid-rich ethanolic extract of rosemary leaves. This effect was accompanied by cell cycle arrest in G0 + G1 phase and a marked inhibition of cell growth. In the in vivo studies, i.p. injections of 2 microg Ro25-4020 in Balb/c mice bearing WEHI-3B D(-) tumors produced a significant delay in tumor appearance and reduction in tumor size, without significant toxicity. Another analog, 1,25-dihydroxy-16,23Z-diene-20-epi-26,27-hexafluoro-19-nor-cholecalciferol (Ro26-3884) administered at the same dose was less effective than Ro25-4020 and profoundly toxic. Importantly, combined treatment with 1% dry rosemary extract (mixed with food) and 1 microg Ro25-4020 resulted in a strong cooperative antitumor effect, without inducing hypercalcemia. These results indicate for the first time that a plant polyphenolic preparation and a vitamin D derivative can cooperate not only in inducing leukemia cell differentiation in vitro, but also in the antileukemic activity in vivo. These data may suggest novel protocols for chemoprevention or differentiation therapy of myeloid leukemia.     

Inhibition of cyclooxygenase-2 indirectly potentiates antitumor effects of photodynamic therapy in mice.

PURPOSE: The aim of the present study was to potentiate the antitumor effectiveness of photodynamic therapy (PDT). A cDNA microarray analysis was used to evaluate the gene expression pattern after Photofrin-mediated PDT to find more effective combination treatment with PDT and inhibitor(s) of the identified gene product(s) overexpressed in tumor cells. EXPERIMENTAL DESIGN: Atlas Mouse Stress Array was used to compare the expression profile of control and PDT-treated C-26 cells. The microarray results have been confirmed using Western blotting. Cytostatic/cytotoxic in vitro assay as well as in vivo tumor models were used to investigate the antitumor effectiveness of PDT in combination with cyclooxygenase (COX) 2 inhibitors. RESULTS: PDT induced the expression of 5 of 140 stress-related genes. One of these genes encodes for COX-2, an enzyme important in the tumor progression. Inhibition of COX-2 in vitro with NS-398, rofecoxib, or nimesulide, or before PDT with nimesulide did not influence the therapeutic efficacy of the treatment. Administration of a selective COX-2 inhibitor after PDT produced potentiated antitumor effects leading to complete responses in the majority of treated animals. CONCLUSIONS: COX-2 inhibitors do not sensitize tumor cells to PDT-mediated killing. However, these drugs can be used to potentiate the antitumor effectiveness of this treatment regimen when administered after tumor illumination.     

G-Csf prevents the suppression of bone marrow hematopoiesis induced by IL-12 and augments its antitumor activity in a melanoma model in mice

Background: IL-12 has been successfully used in experimental tumor therapy. However, administration of this cytokine induces dose-dependent suppression of hematopoiesis that could potentially limit its use in clinical trials. We decided to examine whether the myelosuppressive activity of IL-12 could be corrected by the administration of G-CSF.Materials and methods: In the initial experiments the influence of IL-12 and/or G-CSF on bone marrow and spleen GM-CFC was evaluated. To examine whether G-CSF could influence the antitumor activity of IL-12 the combination therapy with these agents was carried out starting on day seven following inoculation of melanoma MmB16 cells into the footpads of B6D2F₁ mice. To obtain insight into the mechanism of the observed augmented antitumor activity of the combination therapy with IL-12 and G-CSF, the influence of these cytokines on macrophage activity (cytotoxicity and nitric oxide release) was analyzed.Results: In accord with our expectations, the application of G-CSF partially prevented the suppression of bone marrow myelopoiesis in IL-12-treated mice. Unexpectedly, G-CSF also showed potentiation of antitumor effects of IL-12 in this melanoma model. The augmented antitumor activity of combined IL-12/G-CSF immunotherapy could result from the enhanced stimulation of macrophage NO production and cytotoxicity.Conclusion: The simultaneous administration of IL-12 and G-CSF partially prevented suppression of bone marrow myelopoiesis in IL-12-treated mice. Moreover, treatment with these cytokines also results in potentiated antitumor effects in a murine melanoma model.