Antitumor effects of Doxorubicin hydrochloride (dox) and buthionine sulfoximine (bso)-hydroxyapatite (hap) complex on transplanted tumors in-vivo

We prepared hydroxyapatite (HAP) beads containing doxorubicin hydrochloride (DOX) and buthionine sulfoximine (BSO), as a DOX and BSO-HAP complex. When the complex was implanted into mice bearing sarcoma 180 tumor, the antitumor effect of the complex was intensified 1.5-fold, as assessed using tumor volume, on day 27 as compared with that of a complex of DOX-HAP only. Therefore, we concluded that the antitumor effect of the DOX and BSO-HAP complex was increased through depletion of the intracellular radical scavenger glutathione (GSH) by released BSO and subsequently free radicals produced by released DOX.     

Enhancement by hyperthermia of the in vivo antitumour effect of doxorubicin hydrochloride (DOX) and buthionine sulfoximine (BSO)-hydroxyapatite (HAP) complex

We have developed a new type of drug delivery system (DDS) comprising a complex of porous hydroxyapatite (HAP) with the anticancer drug doxorubicin hydrochloride (DOX) and the glutathione inhibitor buthionine sulfoximine (BSO) (DOX and BSO-HAP complex). We then studied the antitumour effect of DOX and BSO-HAP combined with 44 degrees C hyperthermia for 40 min. It was found that in mice this combined treatment suppressed the growth of sarcoma 180 in terms of tumour volume to 36% in comparison viith mice given plain HAP, and was more effective than HAP + hyperthermia or DOX- and BSO-HAP. These results were also confirmed by histological observation.     

Mitogenesis and the search for new targets for anticancer drug design

An exciting new approach to the treatment of cancer is the development of therapeutic strategies which target growth factors and the signal transduction pathways elicited by them. The rationale for targeting the processes which regulate cell proliferation rests on the contention that the malignant phenotype is maintained as a result of alterations in the biochemistry of growth control. The challenge is to design novel anticancer agents which exploit qualitative or quantitative differences in the biochemical elements controlling tumour cell growth and thereby achieve tumour selectivity. A wide variety of drugs are currently under development and include agents which block growth factor-receptor interaction, or which inhibit the action or formation of second messengers such as protein kinase C or phospholipase C. Although in its infancy, the use of inhibitors of growth factor action as antineoplastic agents has already proven effective against some tumours.     

Doxorubicin and mitoxantrone drug eluting beads for the treatment of experimental peritoneal carcinomatosis in colorectal cancer

We investigated the therapeutic efficiency of sulfonate‐modified polyvinyl alcohol beads loaded with doxorubicin, irinotecan or mitoxantrone in vitro and in vivo in a model of experimental peritoneal carcinomatosis (PC). In vitro, cell proliferation was efficiently impaired by doxorubicin drug eluting bead (DEB) treatment while mitoxantrone DEBs were less effective than. Irinotecan showed little effect for both DEBs and free drug. Apoptosis was not different between free mitoxantrone and the DEB form while more apoptosis induction was observed in cells incubated with free doxorubicin and irinotecan. Experimental PC was produced in mice. The therapeutic efficiency of either mitoxantrone and doxorubicin DEB or free drugs were compared. Mice were treated either once on day 12 or by 3 repetitive applications on days 7, 10 and 12. Mice treated by DEBs showed less weight loss and mortality. Therapeutic effect was determined by measuring tumor volume and tumor load on the day 15 after tumor inoculation. For the single application on the day 12, an advantage could be observed for the free drugs. After 3 repeated injections of both free and mitoxantrone DEB no difference in tumor load or tumor volume could be observed. Least tumor load and tumor volume was observed in mice that received 3 repeated injections of doxorubicin DEB. No animal survived 3 injections of free doxorubicin. We conclude that bead encapsulation of chemotherapeutic drugs may show the advantage of less toxicity in peritoneal spread of colorectal cancer. © 2008 Wiley‐Liss, Inc.     

Overcoming tnf-alpha and cddp resistance of a human ovarian-cancer cell-line (c30) by treatment with buthionine sulfoximine in combination with tnf-alpha and or cddp

Previous studies have demonstrated that glutathione (GSH) plays an important role in a wide range of cellular functions including protection, detoxification, transport and metabolism. GSH has been implicated in tumor cell resistance to drugs and/or cytotoxic factors. Buthionine sulfoximine (BSO), a specific inhibitor of gamma-glutamylcysteine synthetase, depletes intracellular GSH and thus could reverse resistance. The present study investigated the effect of BSO used in combination with tumor necrosis factor-alpha (TNF-alpha) or cisdiamminedichloroplatinum (II) (CDDP) on cytotoxicity of a TNF-alpha and CDDP resistant human ovarian cancer cell line (C30). Cytotoxicity was monitored by the MTT assay. Treatment of C30 cells with BSO and CDDP or BSO and TNF-alpha resulted in overcoming resistance and a synergistic cytotoxic effect was obtained. Pretreatment of the tumor cells by either agent for 4 h and wash and followed by the addition of the second agent for 20 h resulted in the same cytotoxicity as observed in the presence of the two agents. Furthermore, combination treatment with BSO, CDDP and TNF-alpha further augmented the synergistic cytotoxic activity achieved by two agents against C30 cells. The protective effect of GSH was shown for TNF-alpha but not for CDDP as treatment of C30 cells with TNF-alpha in combination with GSH or N-acetyl-cysteine (NAC) reduced the cytotoxic effect of TNF-alpha. One mechanism of resistance to TNF-alpha in tumor cells is through the induction of TNF-alpha mRNA and/or protein. The C30 cells did not constitutively express TNF-alpha mRNA, however, treatment of C30 cells with TNF-alpha upregulated the expression of TNF-alpha mRNA. When BSO was used in combination with TNF-alpha, the level of TNF-alpha mRNA induced by TNF-alpha was markedly reduced. Further, incubation of C30 cells with TNF-alpha in conjunction with GSH or NAC also downregulated the expression of TNF-alpha mRNA induced by TNF-alpha. These findings demonstrate that treatment with BSO in combination with TNF-alpha or CDDP can overcome the resistance of C30 tumor cells to TNF-alpha and CDDP. The depletion of intracellular GSH and downregulation of TNF-alpha mRNA by BSO may play a role in the enhanced cytotoxicity seen with the combination of BSO and TNF-alpha. The synergistic effect obtained with a CDDP selected resistant ovarian cancer cell line suggests that treatment with BSO in conjunction with either TNF-alpha or CDDP, or TNF-alpha and CDDP may have a clinical application in the therapy of TNF-alpha and/or CDDP resistant ovarian tumors'     

Enhanced in vitro cytotoxicity of 1,3-bis-(2-chloroethyl)-1-nitrosourea or buthionine sulfoximine combined with a reactive oxygen-generating enzyme immunotoxin

The glutathione inhibitor drugs, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and buthionine sulfoximine (BSO), were tested in vitro in order to assess their cytotoxic effectiveness when combined with an enzyme immunotoxin (eIT) composed of a T-cell reactive monoclonal antibody (mAb) 097 coupled to the reactive oxygen-generating enzyme, glucose oxidase (GO) (EC 1.1.3.4). As targets of this eIT we used mature human T-cells or leukemia cells that expressed the 097 epitope. We found that treatment of the cells with subtoxic amounts of mixtures of both a drug and the 097 eIT markedly potentiated cytotoxicity compared to either drug or eIT alone.     

Implantation treatment method of slow release anticancer doxorubicin containing hydroxyapatite (DOX-HAP) complex. A basic study of a new treatment for hepatic cancer.

We performed an experimental study on slow releasing anticancer drug implantation treatment as a new therapy for hepatocellular carcinoma. Hydroxyapatite (HAP) was chosen for the carrier material and doxorubicin hydrochloride (DOX) for anticancer agent. DOX-HAP was produced by adsorbing DOX to porous HAP particles of 1375 +/- 125 microns diameter using the freeze drying method. In vitro experiments showed slow release of the drug resulting in the steady release of DOX from HAP for 1 month duration. In healthy white rabbits with DOX-HAP implantation in the liver, serum DOX was not detectable, and DOX release rate was stable at the implanted region after 7, 14, and 21 days. When DOX-HAP (DOX; 100 mg kg-1) was administered to mice with sarcoma 180, an improved survival rate was observed without acute toxicity. We also found that VX2 liver tumour growth on white rabbit was inhibited by implantation of DOX-HAP, without acute toxicity. We hope that DOX-HAP implantation therapy will open up new avenues for the treatment of hepatoma.     

SR 4233 (tirapazamine): a new anticancer drug exploiting hypoxia in solid tumours.

SR 4233 (3-amino-1,2,4-benzotriazine 1,4-dioxide, WIN 59075, tirapazamine) is the lead compound in a new class of bioreductive anticancer drugs, the benzotriazine di-N-oxides. It is currently undergoing Phase I clinical testing. The preferential tumour cell killing of SR 4233 is a result of its high specific toxicity to cells at low oxygen tensions. Such hypoxic cells are a common feature of solid tumours, but not normal tissues, and are resistant to cancer therapies including radiation and some anticancer drugs. The killing of these tumour cells by SR 4233, particularly when given on multiple occasions, can increase total tumour cell killing by fractionated irradiation by several orders of magnitude without increasing toxicity to surrounding normal tissues. Topics covered in this review include the rationale for developing a hypoxic cytotoxic agent, the cytotoxicity of SR 4233 as a function of oxygen concentration, the mechanism of action of the drug and its intracellular target and the in vivo evidence that the drug may be useful as an adjunct both to radiotherapy and chemotherapy. Finally, the major unanswered questions on the drug are outlined.     

Prolonged survival of a patient with lung cancer after treatment with S-1, a new oral fluoropyrimidine anticancer drug

A 36-yr-old woman complaining of cough and body weight loss at a health checkup and referred to us after an abnormality was noted on the chest X-ray was diagnosed with clinical stage IV (cT2N3Ml) non-small-cell lung cancer (adenocarcinoma). She received three courses of chemotherapy. The response to treatment was stable disease. She was subsequently enrolled in a clinical trial of S-1, a new oral fluoropyrimidine anticancer drug, and received a total of 22 courses of S-1 over a period of 2 yr 5 mo. At the end of treatment, she was classified as having a partial response. A bronchoscopic biopsy disclosed no cancer cells. Remission continued for 1 yr 7 mo after treatment. The patient died of primary disease 8 yr after the initiation of treatment with oral S-1. Non-small-cell lung cancer was approved as a new indication of S-1 in 2004 in Japan, but the number of patients receiving it for this indication remains limited. Here, we describe our experience with a patient with adenocarcinoma of the lung who survived for a prolonged period after treatment with S-1. Our findings suggest that S-1 is effective for the treatment of non-small-cell lung cancer.     

Monoclonal-antibody against Doxorubicin (dxr) - some characteristics and utilization for dxr-immunoassay

To establish a rapid, specific, sensitive and simple assay method for doxorubicin (DXR) in body fluid, monoclonal antibodies (MAbs) against DXR were generated by immunizing mice with keyhole limpet hemocyanin-DXR conjugate, cell fusion, and a one step, time saving screening ELISA method using aminoplate-coupled DXR via a glutaraldehyde bridge as solid phase antigen. Inhibition ELISA for DXR-immunoassay was established using anti-DXR MAb of the best producer (2E9) and aminoplate-coupled DXR as antigen and DXR ranging from 50 pg to 50 ng in the body fluid or in the cell extract could be detected. MAb 2E9 cross-reacted to various degrees to anthracycline compounds, such as some DXR analogues and derivatives, but did not recognize anthracene and anthraquinone structures.     

Transcatheter arterial embolization using iodized oil (lipiodol) mixed with an anticancer drug for the treatment of hepatocellular carcinoma

The therapeutic results of Lp-TAE (transcatheter arterial embolization with Gelfoam particles preceded by the infusion of a mixture of lipiodol and an anticancer drug via the proper hepatic artery) were evaluated in hepatocellular carcinomas (523 non-resected and 24 resected cases). Excellent therapeutic effects were confirmed not only for the main tumor but also for the the daughter nodules by a histological examination of the liver tissues resected after Lp-TAE. The cumulative 1-year, 2-year and 3-year survival rates in the 523 non-resected cases were 60.4%, 42.9% and 28.0% respectively. These survival rates were all higher than those achieved by Gelfoam TAE. The above results suggest the usefulness of Lp-TAE in the treatment of hepatocellular carcinoma.     

Therapeutic potential and molecular mechanism of a novel sulfonamide anticancer drug, indisulam (E7070) in combination with CPT-11 for cancer treatment

Purpose  

Indisulam (N-(-3-chloro-7-indolyl)-1,4-benzenedisulfonamide; E7070) is an experimental anticancer agent. Microarray analysis indicates that indisulam downregulates several genes involved in drug resistance, and this finding led us to test the effect of combining indisulam with other anticancer drugs. We investigated the antitumor effect and mechanism of synergism when indisulam was administered in combination with CPT-11.     

Combination of cyclosporin A and buthionine sulfoximine (BSO) as a pharmacological strategy for circumvention of multidrug resistance in small cell lung cancer cell lines selected for resistance to doxorubicin.

The small cell lung cancer (SCLC) cell lines U-1285 and U-1690 were adapted to growth in continuous presence of doxorubicin (Dox). The resulting cell lines U-1285R and U-1690R were investigated with respect to sensitivity to the glutathione (GSH) depleting agent buthionine sulfoximine (BSO) and the immunosuppressant cyclosporin A (CsA) as well as the Dox resistance modifying ability of these agents. The parental U-1285 cells were more sensitive to BSO compared to parental U-1690 and the multidrug resistant (MDR) sublines, whereas no difference in sensitivity to CsA was observed between parental and MDR lines. BSO (10 microM) or CsA (1 microgram/ml) alone were able to partially reverse Dox resistance in the MDR cell lines, CsA being only marginally active in U-1285R cells. However, the combination of these two drugs at the same concentrations completely reversed Dox resistance in the MDR U-1690R cells whereas the combination was less effective in the U-1285R cells. The results demonstrate that a combination of low concentrations of BSO and CsA, only partially active by themselves in modifying Dox resistance, may be used as a pharmacological strategy to increase Dox sensitivity in some MDR SCLC cells.     

Epidermal growth factor receptors (EGFR): a new target for anticancer therapy]

Epidermal Growth Factor receptor (EGFR) are a key factor for the tumoral proliferation and its tumoral over expression appears to be a powerful prognosis factor. Currently, 2 types of treatments are targeting EGFR: a monoclonal antibodies anti-EGFR and a specific inhibitors of the EGFR tyrosine kinase. The administration of these compound alone or in combination with chemotherapy gives some promising results. These targets as anti-cancer therapy had emerged to be a new perspective for oncology.     

The pro-oxidant buthionine sulfoximine (BSO) reduces tumor growth of implanted Lewis lung carcinoma in mice associated with increased protein carbonyl,tubulin abundance,and aminopeptidase activity

This study evaluated the effects of the pro-oxidant buthionine sulfoximine (BSO) and of the interaction between BSO and TETRAC, an antagonist of αvß3 integrin, on tumor development and aminopeptidase (AP) activity in a murine model of implanted Lewis’s carcinoma. Male CBA-C57 mice were untreated (controls) or treated with BSO (222 mg/100 mL in drinking water), TETRAC (10 mg/kg/day, i.p.), or BSO + TETRAC. BSO for 28 days and TETRAC were given for the last 20 days. Mice were subcutaneously inoculated with 1?×?10⁶ Lewis carcinoma 3LL cells into the dorsum. Study variables were tumor weight (TW); Hb, as index of tumor-mediated angiogenesis; vascular endothelial growth factor (VEGF) protein abundance; protein carbonyl content; α-tubulin abundance; and GluAp, AlaAp, and AspAp activities. BSO produced a major decrease in TW (203?±?18 mg) with respect to controls (365?±?26) and a reduction in Hb content. The TETRAC group also showed marked reductions in TW (129?±?15) and Hb concentration associated with a reduced VEGF content. The BSO + TETRAC group showed a major TW reduction (125?±?13); although, the difference with the TETRAC group was not significant. BSO treatment increased protein carbonyl and tubulin abundance in comparison to controls. The activity of all APs was increased in the three experimental groups and was strongly and negatively correlated with TW. In conclusion, administration of BSO reduced the TW, which inversely correlated with protein carbonyl content, suggesting a loss of microtubule polymerization. The finding of a negative correlation between TW and AP activity opens up new perspectives for the study of APs as tumor growth modulators.     

Doxorubicin,cyclophosphamide and VP16-213 (ACE) in the treatment of small cell lung cancer

Summary Small cell lung cancer requires aggressive combination chemotherapy. The three active agents, doxorubicin (A) 45 mg/m² i.v. day 1, cyclophosphamide (C) 1.0 mg/m² i.v. day 1 and VP16-213 (E) 50 mg/m²/day i.v. days 1–5 were given together. The combination (ACE) was given every 21 days without chest irradiation. One hundred and seventy-four patients have been stratified for extent of disease and randomized on three sequential studies testing ACE vs ACE + MER immunotherapy (38 patients), or ACE vs ACE alternating with CCNU, methotrexate, vincristine and procarbazine (109 patients), or ACE vs ACE II (ACE with continuous VP16-213-100 mg/m²/dayx5 days-27 patients-ongoing). The immunotherapy and the alternating non-cross resistant combination have not proven beneficial with respect to response or survival. The ACE combination, regardless of additional treatments, has produced greater than 90% response overall. In limited disease the complete response (CR) frequency is 65%. The median survival for limited disease overall is 14 months and 18 months for patients achieving CR. In extensive disease the CR frequency is 40% with a median survival of 9 months overall and 13 months for patients achieving CR. Response frequency and survival are identical in the first two studies and 20–30% of patients with limited disease are long-term survivors with one late relapse (>3 years). Patients who achieved CR had a significantly longer survival regardless of other factors such as performance status or extent of disease. Prophylactic cranial irradiation was demonstrated to be useful in prevention or delaying CNS metastases in patients who achieved CR. The third generation study of high-dose VP16-213 infusion seeks to increase the CR frequency. ACE chemotherapy without chest irradiation is a highly effective treatment for all patients with small cell lung cancer and compares favorably with all other studies with or without adjuvant radiotherapy.This investigation was supported in part by PHS Grant Number 1 P50CA 32107-01 awarded by the National Cancer Institute, DHHS     

A fibrin clot containing of anticancer drug for intra-arterial chemo-embolization therapy. (2) Chemotherapeutic effects on a model hepatoma using VX-2 carcinoma in rabbits

The chemotherapeutic and ischemic effects of a fibrin clot containing mitomycin-C were observed on a model of primary hepatoma using VX-2 carcinoma inoculated in to the subcapsule of the liver of rabbits. The results of antitumor effect suppression of pulmonary and intrahepatic metastases and survival time using the fibrin clot containing mitomycin-C were better than with other treatments, namely a one-shot infusion of MMC or embolization with fibrin clot only. A synergistic antitumor effect was obtained using embolization with the fibrin clot incorporating mitomycin-C. Using direct subcapsular inoculation with a VX-2 carcinoma block a solitary hepatic tumor was obtained which was hypervascular and resembled human primary hepatoma. These results suggested that a fibrin clot containing an anticancer drug is safe a and effective modality for hepatic or other arterial embolization therapies.