melphalan and perfosfamide

In vitro drug sensitivity of tumour biopsies is currently being determined using a variety of methods. For these chemosensitivity assays many drugs are required at short notice, and this in turn means that the drugs must generally be stored in solution. There are, however, a number of potential problems associated with dissolving and storing drugs for in vitro use, which include (a) drug adsorption; (b) effects of freezing; (c) drug stability under the normal conditions of dilution and setting up of an in vitro assay; and (d) insolubility of drugs in normal saline (NS) or phosphate-buffered saline (PBS). These problems are considered in general, and some recommendations for use of solutions of drugs in in vitro assays are suggested. The nitrosoureas and alkylating agents are also investigated in greater detail in this respect. The nitrosoureas are found to be very labile in PBS at pH 7, with 5% degradation (t0.95) occurring in 10-50 min at room temperature. These values are increased about 10-fold on refrigeration and about 5- to 10-fold on reduction of the pH of the medium to pH 4-5. At pH 7 and room temperature, t0.95 is observed in under 1 h with the alkylating agents nitrogen mustard, chlorambucil, melphalan, 2,5-diaziridinyl-3,6-bis(2-hydroxyethylamino)-1,4-benzoquinone (BZQ), dibromodulcitol, dibromomannitol, treosulphan, and procarbazine. Of the other alkylating agents, 4-hydroperoxycylophosphamide (sometimes used in vitro in place of cyclophosphamide), busulphan, dianhydrogalactitol, aziridinylbenzoquinone (AZQ), and dacarbazine have a t0.95 of between 2 and 24 h, while ifosfamide and pentamethylmelamine are both stable in aqueous solution for greater than 7 days. About half the drugs studied in detail have been stored frozen in solution for in vitro use, although very little is known about their stability under these conditions.

Topics: Alkylation; Antineoplastic Agents; Carmustine; Chlorambucil; Colony-Forming Units Assay; Cyclophosphamide; Drug Storage; Hydrogen-Ion Concentration; Lomustine; Mathematics; Melphalan; Nimustine; Nitrosourea Compounds; Solutions; Temperature; Tumor Stem Cell Assay

In August 1988 we began a program in which multiple myeloma patients achieving < or = 10% marrow plasma cells and > or = 50% reduction in paraprotein levels after the VAD (vincristine, doxorubicin, dexamethasone) regimen underwent bone marrow harvest, ex vivo marrow purging with 4-hydroperoxycyclophosphamide (4-HC) and marrow cryopreservation. Conditioning with a regimen of high-dose busulfan (total dose 16 mg/kg), cyclophosphamide (120 mg/kg) and melphalan (90 mg/m2) (BU + CY + MEL) followed by autologous BMT was then carried out. Seventeen of the 24 patients who received VAD (71%, 95% confidence interval [CI] 49 to 87%) were eligible for bone marrow harvest. One patient was not harvested because of non-medical reasons; two patients who underwent marrow harvest had gross plasmacytosis present in biopsies performed intraoperatively and did not undergo BMT. Fourteen patients (58%, 95% CI 37 to 78%) received BU + CY + MEL and 4-HC-purged autologous BMT. The median time to recovery of 0.5 x 10(9)/l neutrophils was 19 days (range 14 to 26) while the last platelet transfusion was given on a median of day 32 (range 10 to 46) post-BMT in the evaluable patients. The major non-hematologic toxicity was hepatic; two patients in complete remission died of hepatic veno-occlusive disease. Another patient succumbed to fungal infection despite neutrophil recovery. The remaining 11 patients achieved responses (complete in six and partial in five) associated with a normal performance status.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Antineoplastic Combined Chemotherapy Protocols; Bone Marrow Purging; Bone Marrow Transplantation; Busulfan; Clinical Protocols; Combined Modality Therapy; Cyclophosphamide; Cytarabine; Dexamethasone; Female; Humans; Life Tables; Male; Melphalan; Middle Aged; Multiple Myeloma; Survival Analysis; Transplantation, Autologous; Vincristine

Drug interactions may dictate the failure or success of a treatment. Patients undergoing hematopoietic stem cell transplantation (HSCT) are exposed to various types of drugs, and understanding how these drugs interact is of the utmost importance. The pharmacokinetics of busulfan, melphalan, and cyclophosphamide, drugs commonly used for HSCT, are known to be affected by a variety of other drugs with differing molecular structures. We hypothesized that these structurally unrelated drugs affect the transport of DNA-alkylating agents. To test this hypothesis, we developed a flow cytometry assay that used 5-carboxyfluorescein diacetate acetoxymethyl ester, which is cleaved by nonspecific intracellular esterases to 5-carboxyfluorescein (5-CF), a fluorescent ligand for the drug transporter MRP1. A decreased 5-CF efflux in the presence of a test compound suggests competitive inhibition. We demonstrated that chlorambucil, 4-hydroperoxycyclophosphamide, ketoconazole, ethacrynic acid, everolimus, and sirolimus strongly inhibited 5-CF efflux in lymphoma and leukemia cell lines. The efflux of these drugs partially depends on the glutathione (GSH) level, and their cytotoxicity is synergistic with inhibited GSH synthesis. This is consistent with the hypothesis that their GSH-conjugated products are ligands of a common cellular drug transporter. Our results may explain clinical observations on the effects of various drugs on the pharmacokinetics and pharmacodynamics of alkylating agents, and the assay may be used to deduce interaction mechanisms of drugs transported by a common system.

Topics: Antineoplastic Agents, Alkylating; Biological Transport; Busulfan; Cell Line, Tumor; Cell Survival; Chlorambucil; Cyclophosphamide; Drug Interactions; Ethacrynic Acid; Everolimus; Flow Cytometry; Fluoresceins; Humans; Ketoconazole; Melphalan; Multidrug Resistance-Associated Proteins; Reproducibility of Results; Sirolimus

Bone marrow stromal cell function is a critical influence on hematopoietic reconstitution following progenitor or stem cell transplantation. Stromal cells support hematopoietic cell migration, survival, and proliferation. We have previously reported that stromal cell matrix metalloproteinase-2 (MMP-2) is necessary for optimal support of pro-B-cell chemotaxis through its regulation of stromal cell-derived factor-1 (CXCL12) release. Following exposure to the topoisomerase II inhibitor, etoposide (VP-16), stromal cell MMP-2 protein expression is reduced. The current study investigated the mechanism by which VP-16 may alter translation of MMP-2 in bone marrow stromal cells.. Bone marrow stromal cells were exposed to chemotherapeutic agents etoposide, melphalan, and 4-hydroperoxycyclophosphamide (4HC) and evaluated for MMP-2 expression by enzyme-linked immunosorbent assay and support of pro-B-cell chemotaxis by chemotaxis assay. Western blot analyses were completed to evaluate phosphorylation of stromal cell translational regulatory proteins 4E binding protein-1 (4EBP-1), P70(S6K), and S6 or MMP-2 in the presence of chemotherapy, or the chemical inhibitors rapamycin or LY294002.. Rapid dephosphorylation of 4EBP-1, P70(S6K), and S6 following VP-16 exposure was observed, consistent with blunted translational efficiency. We also observed that inhibition of stromal cell mammalian target of rapamycin with rapamycin, or phosphatidylinositol 3 kinase with LY294002, resulted in inhibition of stromal cell MMP-2 protein. In addition we found that the chemotherapeutic agents melphalan and 4HC disrupt bone marrow stromal cell MMP-2 protein expression and support of chemotaxis.. These data suggest that one mechanism by which chemotherapy may alter stromal cells of the bone marrow microenvironment is through disrupted translation of proteins.

Topics: Adaptor Proteins, Signal Transducing; Animals; Antimetabolites, Antineoplastic; Bone Marrow Cells; Cell Cycle Proteins; Cell Line; Cyclophosphamide; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Etoposide; Humans; Matrix Metalloproteinase 2; Melphalan; Mice; Phosphatidylinositol 3-Kinases; Phosphoproteins; Phosphorylation; Protein Kinases; Protein Serine-Threonine Kinases; Ribosomal Protein S6; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Sirolimus; Stromal Cells; Structure-Activity Relationship; TOR Serine-Threonine Kinases

Loss of DNA mismatch repair is a common finding in hereditary non-polyposis colon cancer as well as in many types of sporadic human tumours. We compared the effect of loss of DNA mismatch repair on drug sensitivity as measured by a clonogenic assay with its effect on the ability of the same drug to enrich for mismatch repair-deficient cells in a proliferating tumour cell population. Mixed populations containing 50% DNA mismatch repair-deficient cells constitutively expressing green fluorescent protein and 50% mismatch repair-proficient cells were exposed to different chemotherapeutic agents. 6-Thioguanine, to which DNA mismatch repair-deficient cells are known to be resistant, was included as a control. The results in the cytotoxicity assays and in the enrichment experiments were concordant. Treatment with either carboplatin, cisplatin, doxorubicin, etoposide or 6-thioguanine resulted in enrichment for mismatch repair-deficient cells, and clonogenic assays demonstrated resistance to these agents, which varied from 1.3- to 4.8-fold. Treatment with melphalan, paclitaxel, perfosfamide or tamoxifen failed to enrich for mismatch repair-deficient cells, and no change in sensitivity to these agents was detected in the clonogenic assays. These results identify the topoisomerase II inhibitors etoposide and doxorubicin as additional agents for which loss of DNA mismatch repair causes drug resistance. The concordance of the results from the two assay systems validates the enrichment assay as a rapid and reliable method for screening for the effect of loss of DNA mismatch repair on sensitivity to additional drugs.

Topics: Adenocarcinoma; Antineoplastic Agents; Carboplatin; Cell Separation; Cisplatin; Colorectal Neoplasms; Cyclophosphamide; DNA Repair; DNA, Neoplasm; Doxorubicin; Enzyme Inhibitors; Etoposide; Humans; Melphalan; Paclitaxel; Tamoxifen; Thioguanine; Tumor Cells, Cultured; Tumor Stem Cell Assay

It is vital to develop effective therapy for children with acute lymphoblastic leukemia (ALL), in whom no remission occurs or who suffer relapse with current protocols. Cellular drug resistance is thought to be an important cause of induction failure and relapse. We performed in vitro tests of bone marrow samples in 196 children with newly diagnosed ALL with a 4-day culture and a methyl-thiazol-tetrazolium assay. We tested 16 drugs and calculated the 70% lethal dose (LD70) for 14 drugs and the leukemic cell survival (LCS) rate for dexamethasone and prednisolone. For each single drug, patients were classified into two groups, sensitive or resistant, by median concentration of LD70 or LCS. When patients were classified into three groups by sensitivity to four drugs of DPAV (dexamethasone, prednisolone, L-asparaginase, and vincristine), 3-year event-free survival (EFS; 95% confidence intervals) of the super sensitive group (SS; sensitive to all 4 drugs) was 0.833 (0.690 to 0.976), that of the intermediate sensitive group (IS; sensitive to 2 or 3 drugs) was 0.735 (0.609 to 0.863), and that of the relatively resistant group (RR; sensitive to no drugs or to 1 drug) was 0.541 (0.411 to 0.670; P = .0008). We then investigated the relationship between the above four-drug sensitivity and the time of relapse. The SS and IS patients tended to maintain continuous complete remission, and RR patients tended to undergo induction failure and early and late relapse (P = .004). Initial white blood cell count, immunologic classification, and age were also predictive factors, but the patient numbers showed no statistical correlation between these factors and the four-drug sensitivity groups (SS, IS, and RR). When we took three groups SS/IS/RR and investigated the EFS for various clinical groups, DPAV sensitivity strongly influenced EFS in the standard-risk ALL (P = .016). In vitro drug sensitivity testing provides additional prognostic information about childhood ALL, and early detection of drug resistance at the time chemotherapy commences may provide a successful strategy for individualizing treatment, as the results indicate de novo resistance to front-line drugs and suggest alternative, second-line drugs.

Topics: Aclarubicin; Adolescent; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Asparaginase; Bleomycin; Bone Marrow; Cell Survival; Child; Child, Preschool; Cyclophosphamide; Cytarabine; Daunorubicin; Dexamethasone; Disease-Free Survival; Dose-Response Relationship, Drug; Doxorubicin; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Etoposide; Follow-Up Studies; Humans; Infant; Infant, Newborn; Life Tables; Melphalan; Methotrexate; Mitomycin; Mitoxantrone; Neoplastic Stem Cells; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Prednisolone; Prognosis; Recurrence; Remission Induction; Tumor Cells, Cultured; Vincristine

The aim of these studies was to determine whether chemotherapy-resistant tumor cell sublines derived from a single starting cell population with identical treatment protocols, have the same mechanism of resistance.. Twelve cyclophosphamide-resistant sublines were derived from KHT-iv murine sarcoma cells by repeated exposures to 2, 4, or 8 microg/ml doses of 4-hydroperoxycyclophosphamide (4-OOHCP). To investigate possible mechanisms of resistance, glutathione (GSH) levels, glutathione S-transferase (GST) activity, and aldehyde dehydrogenase (ALDH) activity were determined. In addition, studies with the GSH depletor buthionine sulfoximine (BSO) and the ALDH inhibitor diethylamino-benzaldehyde (DEAB) were undertaken.. Resistant factors to 4-OOHCP, assessed at 10% clonogenic cell survival, ranged from 1.5-7.0 for the various cell lines. Crossresistance to melphalan and adriamycin also were commonly observed. Increased GSH levels, GST activity and ALDH activity were detected in the sublines but not all exhibited the same pattern of biochemical alterations. The response to GSH and ALDH inhibitors also varied among the sublines; the resistance being reversible in some cell lines but not others.. The present results indicate that when resistant sublines are derived simultaneously from the same starting cell population, the observed mechanisms of resistance may not be the same in each of the variants. These findings support the hypothesis that preexisting cellular heterogeneity may affect mechanisms of acquired resistance.

Topics: Aldehyde Dehydrogenase; Animals; Antineoplastic Agents, Alkylating; Cyclophosphamide; Drug Resistance, Neoplasm; Glutathione; Glutathione Transferase; Melphalan; Mice; Neoplasm Proteins; Sarcoma, Experimental; Tumor Cells, Cultured

Loss of DNA mismatch repair is a common finding in many types of sporadic human cancers as well as in tumors arising in patients with hereditary nonpolyposis colon cancer. The effect of the loss of DNA mismatch repair activity on sensitivity to a panel of commonly used chemotherapeutic agents was tested using one pair of cell lines proficient or deficient in mismatch repair due to loss of hMSH2 function and another due to loss of hMLH1 function. 6-Thioguanine and N-methyl-N'-nitro-N-nitrosoguanidine, to which these cells are known to be resistant, were included in the panel as controls. The results were concordant in both pairs of cells. Loss of either hMSH2 or hMLH1 function was associated with low level resistance to cisplatin, carboplatin, and etoposide, but there was no resistance to melphalan, perfosfamide, 5-fluorouracil, doxorubicin, or paclitaxel. The results are consistent with the concept that the DNA mismatch repair proteins function as a detector for adducts produced by 6-thioguanine, N-methyl-N'-nitro-N-nitrosoguanidine, cisplatin, and carboplatin but not for melphalan and perfosfamide. They also suggest that these proteins play a role in detecting the DNA damage produced by the binding of etoposide to topoisomerase II and propagating signals that contribute to activation of apoptosis.

Topics: Adaptor Proteins, Signal Transducing; Adenocarcinoma; Antineoplastic Agents; Carboplatin; Carrier Proteins; Cisplatin; Colorectal Neoplasms; Cyclophosphamide; DNA Adducts; DNA Damage; DNA Repair; DNA-Binding Proteins; DNA, Neoplasm; Doxorubicin; Drug Resistance, Neoplasm; Endometrial Neoplasms; Etoposide; Female; Fluorouracil; Humans; Melphalan; Methylnitronitrosoguanidine; Mutagenesis; MutL Protein Homolog 1; MutS Homolog 2 Protein; Neoplasm Proteins; Nuclear Proteins; Paclitaxel; Proto-Oncogene Proteins; Thioguanine; Tumor Cells, Cultured

Cyclocreatine, an analog of creatine, is an efficient substrate for creatine kinase, but its phosphorylated form is a poor phosphate donor in comparison with creatine phosphate. Cyclocreatine was not very cytotoxic upon 24 h of exposure of human SW2 small-cell lung cancer cells to concentrations of up to 5 mM. However, combinations of cyclocreatine (0.5 mM, 24 h) with each of four antitumor alkylating agents, cis-diamminedichloroplatinum(II), melphalan, 4-hydroperoxycyclophosphamide, and carmustine, resulted in additive to greater-than-additive cytotoxicity toward exponentially growing SW2 cells. The greatest levels of synergy were seen at higher concentrations of 4-hydroperoxycyclophosphamide and carmustine as determined by isobologram analysis. In vivo cyclocreatine (0.5 or 1 g/kg) was more effective if given i.v. rather than i.p. The longest tumor-growth delays, up to 10 days, were produced by extended regimens of cyclocreatine. Cyclocreatine was an effective addition to therapy with standard anticancer agents including cis-diamminedichloroplatinum(II), cyclophosphamide, Adriamycin, or 5-fluorouracil. No additional toxicity was observed when 10 days of cyclocreatine treatment was given with full standard-dose regimens of each drug. The resultant increases in tumor-growth delay were 1.7- to 2.4-fold as compared with those obtained for each of the drugs alone. These results indicate that cyclocreatine may be an effective single agent and an effective addition to combination chemotherapy regimens.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Carcinoma, Small Cell; Carmustine; Cell Division; Cell Survival; Cisplatin; Creatinine; Cyclophosphamide; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Female; Humans; Injections, Intraperitoneal; Injections, Intravenous; Lung Neoplasms; Mammary Neoplasms, Experimental; Melphalan; Rats; Rats, Inbred F344; Tumor Cells, Cultured

Although the antiangiogenic agent TNP-470 does not, in general, increase the cytotoxicity of anti-cancer therapies in cell culture, the antiangiogenic agents TNP-470 and minocycline individually and especially in combination have been shown to increase the tumor growth delay produced by several standard cytotoxic therapies in the Lewis lung carcinoma. In an effort to understand the mechanism by which the antiangiogenic agent combination TNP-470/minocycline potentiates the antitumor activity of cytotoxic therapeutic agents in vivo, the biodistribution of [14C]-cyclophosphamide and cis-diamminedichloroplatinum(II) was determined 6 h after cytotoxic drug administration in animals bearing Lewis lung carcinoma pretreated with TNP-470/minocycline and in animals without pretreatment. Higher levels of 14C and platinum were found in 9 tissues (including tumor) except blood in animals pretreated with TNP-470/minocycline. The increased drug levels in the tumors may be sufficient to account for the increased tumor growth delays observed previously. DNA alkaline elution of tumors from animals pretreated with TNP-470/minocycline showed increased DNA cross-linking by both cyclophosphamide and cis-diamminedichloroplatinum(II). The possible implications of these results are discussed.

Topics: Animals; Antineoplastic Agents; Carcinoma, Lewis Lung; Carmustine; Cell Hypoxia; Cell Survival; Cisplatin; Cyclohexanes; Cyclophosphamide; DNA, Neoplasm; Drug Combinations; Male; Melphalan; Mice; Mice, Inbred C57BL; Minocycline; O-(Chloroacetylcarbamoyl)fumagillol; Platinum; Sesquiterpenes; Tumor Cells, Cultured

We evaluated the antitumor activity of busulfan against a panel of tumor cell lines and xenografts in athymic nude mice derived from childhood high-grade glioma, adult high-grade glioma, ependymoma, and medulloblastoma. Busulfan displayed similar activity against a panel of four medulloblastoma cell lines (D283 Med, Daoy, D341 Med, and D425 Med) and four corresponding sublines with laboratory-generated or clinically acquired resistance to 4-hydroperoxycyclophosphamide [D283 Med (4-HCR), Daoy (4-HCR), D341 Med (4-HCR), and D458 Med] and cross-resistance to melphalan. This is consistent with a nearly total lack of cross-resistance of busulfan to 4-hydroperoxycyclophosphamide. Busulfan was active in the therapy of all but one of the subcutaneous xenografts tested, with growth delays ranging from 14.3 days in D612 EP to 58.4 days in D528 EP. Busulfan produced statistically significant increases in the median survival of mice bearing intracranial D456 MG (66%-90%), D612 EP (18%-33%), and D528 EP (89%) xenografts. These studies suggest that busulfan may be active against medulloblastomas, high-grade gliomas, and ependymomas as well as against cyclophosphamide-resistant neoplasms.

Topics: Animals; Brain Neoplasms; Busulfan; Child, Preschool; Cyclophosphamide; Female; Humans; Injections, Intraperitoneal; Male; Medulloblastoma; Melphalan; Mice; Mice, Nude; Neoplasm Transplantation; Transplantation, Heterologous; Tumor Cells, Cultured

We initiated this study to determine whether three structurally related bifunctional alkylating agents could induce the expression of a presumptive human DNA repair gene. The gene chosen for this study is known to encode the ribosomal phosphoprotein PO, but ironically may also share functions related to DNA repair. We now show by Northern analysis that PO is induced by L-phenylalanine mustard, 4-hydroperoxycyclophosphamide and mechlorethamine, which are DNA-damaging agents commonly used as chemotherapeutic antitumor agents. In further support of its involvement in DNA repair is the finding of a 30- to 50-fold constitutive overexpression of the PO gene in human tumor cell lines that are Mer-, cells which lack O6-methylguanine methyltransferase activity, when compared to Mer+ cell lines. This constitutively elevated level of PO in Mer- cell lines, which are thus DNA repair defective for O6-alkyguanine lesions, was not observed for other genes tested, including the human ribosomal gene S17 whose mRNA steady-state levels were uniformly the same in both Mer- and Mer+ cells. Taking these data together, it appears that increased levels of PO are somehow linked to DNA repair, and increased expression of PO may compensate for the decreased O6-methylguanine DNA methyltransferase activity in Mer- cells. Furthermore, the PO gene has also been shown to be overexpressed in colorectal tumors and polyps and the sera of some systemic lupus erythematosus patients contain antibodies against PO. The titer of the anti-PO antibodies rises significantly during lupus psychosis.

Topics: Antineoplastic Agents; Blotting, Northern; Blotting, Southern; Cyclophosphamide; DNA Probes; DNA Repair; Electrophoresis, Agar Gel; Gene Expression; Humans; Mechlorethamine; Melphalan; Methyltransferases; O(6)-Methylguanine-DNA Methyltransferase; Phosphoproteins; Ribosomal Proteins; Tumor Cells, Cultured

Alkylating agents have been used individually and in combination to treat epithelial ovarian carcinoma. In this study, the cytotoxicity of 7 alkylating agents has been measured using a serial dilution clonogenic assay. When individual agents were evaluated, markedly different activity was observed against several ovarian cancer cell lines. Among 4 cell lines tested, OVCA 432 was the most sensitive to cisplatin, thiotepa and melphalan. When alkylating agents were used in combination against OVCA 432, synergistic activity was observed with cisplatin and each of several other alkylating agents including thiotepa, melphalan, 4-hydroperoxycyclophosphamide (4HC) and carboplatin. The combination of cisplatin and thiotepa also exerted synergistic activity against the OVCA 420, 429 and 433 cell lines, but had only additive or subadditive activity against the NIH:OVCAR-3 cell line. Sequential treatment of tumor cell lines with the different alkylating agents was as effective as simultaneous treatment. Synergistic anti-tumor activity in cell culture is consistent with clinical observations that alkylating agents in combination appear more effective than single agents for treatment of advanced epithelial ovarian cancer. In addition, our study suggests that cisplatin in combination with thiotepa, 4HC or melphalan might prove useful for high-dose therapy with autologous bone-marrow support.

Topics: Alkylating Agents; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Carcinoma, Squamous Cell; Cell Division; Cisplatin; Cyclophosphamide; Drug Synergism; Female; Humans; Melphalan; Ovarian Neoplasms; Thiotepa; Tumor Cells, Cultured

Intensive chemotherapy prior to harvesting autologous bone marrow may be advantageous for cancers that infiltrate the bone marrow. This approach, however, may deplete hemopoietic reserves or damage the hemopoietic microenvironment and thereby jeopardize posttransplant engraftment; in vitro treatment of bone marrow to ensure a tumor-free state may enhance the risk of nonengraftment. We addressed these concerns in a pilot study of patients with disseminated neuroblastoma. Bone marrow was harvested after initial intensive therapy that included 1) three to six courses of very high dose cyclophosphamide (CPM) (100-140 mg/kg in five patients, 140-160 mg/kg in nine patients), plus doxorubicin and vincristine, followed by 2) a median of three strongly myelosuppressive courses of cisplatin/VP16. The median interval between courses was 23 days. The marrow was treated in vitro with the CPM congener 4-hydroperoxycyclophosphamide (4-HC) and cryopreserved. It was infused after a massive cytoreduction regimen of melphalan 180 mg/m2 (n = 7) or thiotepa 900 mg/m2 (n = 7), plus cisplatin, BCNU, VP16, and local radiation. All 14 patients reconstituted hemopoiesis (median of 37 days to neutrophils greater than or equal to 500/microliter and of 63 days to platelets greater than 50,000/microliters). The number per kilogram body weight of hemopoietic progenitor cells (CFU-GM, BFU-E) in the autografts correlated significantly with the rate of hematologic recovery. Preharvest CPM dosage, however, did not. The use of thiotepa, as opposed to melphalan, was associated with a significantly slower posttransplant platelet recovery, suggesting a possible adverse effect of high-dose thiotepa on posttransplant hemopoiesis. In sum, while reinforcing evidence of a stem cell sparing effect of CPM, this pilot study more importantly delineates the degree to which high-dose alkylator therapy can be exploited to attain maximal dose intensity beginning at diagnosis. This aggressive treatment approach may have wide applicability, since CPM is among the most active agents against a spectrum of pediatric cancers.

Topics: Adolescent; Antineoplastic Combined Chemotherapy Protocols; Blood Platelets; Bone Marrow; Bone Marrow Transplantation; Child, Preschool; Cisplatin; Cyclophosphamide; Doxorubicin; Etoposide; Hematopoiesis; Humans; Infant; Melphalan; Neuroblastoma; Neutrophils; Thiotepa; Vincristine

A panel of four cell sublines, each selected for resistance to a different antineoplastic agent, has been developed from a human malignant melanoma cell line G3361. Following repeated exposure to escalating doses of the drug of interest, cloned sublines were developed that are 9-fold resistant to cisplatin (G3361/CP), 11-fold resistant to 4-hydroxyperoxy-cyclophosphamide (4-HC) (G3361/HC), 4-fold resistant to carmustine (BCNU) (G3361/BCNU), and 4-fold resistant to melphalan (G3361/PAM). The cross-resistance of each resistant cell line was determined for cisplatin, BCNU, 4-HC, melphalan, carboplatin, nitrogen mustard, and Adriamycin. In general, the alkylating agent-resistant cell lines were specifically resistant to the drug used for selection with the exception of the G3361/CP line, which was greater than 10-fold resistant to the cisplatin analogue carboplatin, 4-fold resistant to 4-HC, and slightly (1.5-fold) resistant to melphalan, and the G3361/BCNU line, which was slightly (1.8-fold) resistant to melphalan. Collateral sensitivity of the G3361/CP, G3361/PAM, and G3361/4HC lines to killing by BCNU was also observed. Glutathione-S-transferase activity was elevated in each of the alkylating agent-resistant cell lines by 3- to 5-fold with chlorodinitrobenzene substrate. On Western blotting, the glutathione-S-transferase-pi (GST-pi) isoenzyme protein was elevated in the resistant cells by 3- to 5-fold. A complementary DNA (pTS4-10) coding for GST-pi has been cloned from a lambda gt11 library, sequenced, and used as a probe to determine the relative levels of GST-pi mRNA in the alkylating agent-resistant cell lines. GST-pi mRNA levels were elevated (8- to 15-fold) in the resistant cell lines, indicating that the GST-pi increases were mediated through an increase in mRNA levels. GST-pi elevations are a frequent event in cells selected for alkylating agent resistance, and in some cases, of multiple drug resistance. However, the lack of cross-resistance among cell lines selected for resistance to different alkylating agents, all of which have elevated GST-pi levels, indicates that increased levels of GST-pi cannot be the predominate mechanism for resistance to the tested drugs in these cell lines.

Topics: Alkylating Agents; Antineoplastic Agents; Blotting, Northern; Carmustine; Cell Line; Cell Survival; Clone Cells; Cyclophosphamide; Drug Resistance; Glutathione Transferase; Humans; Melanoma; Melphalan; RNA, Neoplasm; Tumor Cells, Cultured

The sensitivity of myeloid leukaemic colony forming cells (AML-CFC), to five cytotoxic drugs has been compared in two culture systems with the sensitivity of normal myeloid progenitor cells (GM-CFC). No increased sensitivity was found for AML-CFC to any of the chemotherapeutic agents studied. AML-CFC were significantly less sensitive than normal GM-CFC to mafosfamide at the doses commonly used to purge bone marrow autografts. It is suggested that AML cells probably display similar sensitivity to cytotoxic agents as normal myelopoietic cells at a similar stage of differentiation. Hence complete elimination of the leukemic clone by pharmacological purging may be incompatible with bone marrow re-engraftment. We conclude that purging AML autografts with any of the agents examined has little scientific basis.

Topics: Antineoplastic Agents; Bone Marrow; Bone Marrow Transplantation; Cell Survival; Clone Cells; Cyclophosphamide; Cytarabine; Etoposide; Granulocytes; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid, Acute; Melphalan; Transplantation, Autologous; Tumor Cells, Cultured

The toxicities of 4-hydroperoxycyclophosphamide (4-OOH CY), phosphoramide mustard (PM), melphalan (MEL) and busulphan (BU) have been compared in Chinese hamster cells, V-79-753B. The initial total amount of cross-linking was a determining factor for the clonogenic survival of cells treated with MEL or PM. Although 4-OOH CY generated cross-links in this cell line, this damage did not account for the toxicity of the compound. There was no evidence for cross-link formation in cells treated with BU, even at a dose of the drug (1000 micrograms/ml) that was too toxic to measure clonogenic survival. Comparison for the four compounds at equitoxic doses showed that both PM and MEL caused the arrest of the cell cycle at G2 which persisted after drug removal. This was accompanied by a decline in the population growth rate and a decrease in total cell count. In contrast, both BU and 4-OOH CY caused a temporary arrest of the cell cycle G2, 24 hr after drug removal. However, the cell cycle distribution returned the control values within 3-4 days after treatment. Both BU and 4-OOH CY showed little effect on the initial growth rate of the cells. It is concluded that the initial amount of cross-links contributes to the toxicity of PM and MEL. However, it is unlikely that the generation of cross-links is of major importance for the toxicity of either 4-OOH CY or BU.

Topics: Alkylating Agents; Animals; Busulfan; Cell Cycle; Cell Line; Cell Survival; Cricetinae; Cricetulus; Cyclophosphamide; Dose-Response Relationship, Drug; Female; Half-Life; Melphalan; Ovary; Phosphoramide Mustards

The case of a 4 year 8 months old boy with neuroblastoma of unknown primary, metastatic to the bone and to the bone marrow is presented. After achieving a partial remission with six cycles of conventional chemotherapy, the patient was given supraconventional chemotherapy (melphalan 220 mg/m2 bolus i.v.) in an effort to eliminate residual disease. Prior to the administration of the drug, 560 cc of autologous bone marrow, morphologically free of tumor was harvested (total 110 X 10(8) nucleated cells) and concentrated to a mononuclear cell fraction with a total of 10 X 10(8) cells. After in vitro purging with the stable metabolite of 4-hydroperoxycyclophosphamide ASTA Z 7654 (40 micrograms/2 X 10(7) mononuclear cells/ml), the mononuclear cell suspension was retransfused 10 hours following the application of high dose melphalan. Hemopoietic reconstitution was delayed with a platelet count reaching 70,000/microliter only after seven months. At the time of this writing (20 months after diagnosis and 16 months after autologous bone marrow transplantation) there is no evidence for active disease according to the bone scan and multiple bone marrow biopsies. In view of the dismal prognosis of patients with neuroblastoma, stage IV it is recommended that further patients should be treated with a slightly modified protocol of the cooperative austrian neuroblastoma study.

Topics: Antineoplastic Combined Chemotherapy Protocols; Bone Marrow; Bone Marrow Transplantation; Bone Neoplasms; Child, Preschool; Cyclophosphamide; Humans; Male; Melphalan; Neoplasm Staging; Neoplasms, Unknown Primary; Neuroblastoma

The ex vivo sensitivity of murine pluripotent hematopoietic stem cells (CFU-S) and myeloid progenitor cells (CFU-GM) to 4-hydroperoxycyclophosphamide, ASTA Z 7557, phosphoramide mustard, acrolein, melphalan, and cis-platinum was determined in the absence and presence of known (disulfiram, diethyldithiocarbamate, cyanamide) or suspected [ethylphenyl(2-formylethyl)phosphinate] inhibitors of aldehyde dehydrogenase activity. As compared to CFU-GM, CFU-S were less sensitive to the oxazaphosphorine agents, 4-hydroperoxycyclophosphamide and ASTA Z 7557. The two cell populations were approximately equisensitive to acrolein as well as to the non-oxazaphosphorine cross-linking agents, phosphoramide mustard, melphalan and cis-platinum. All four inhibitors of aldehyde dehydrogenase activity potentiated the cytotoxic action of the oxazaphosphorines toward CFU-S; they did not potentiate the cytotoxic action of acrolein or the non-oxazaphosphorines toward these cells. The inhibitors did not potentiate the cytotoxic action of the oxazaphosphorines, non-oxazaphosphorines, or acrolein toward CFU-GM. Pyridoxal, a substrate for aldehyde oxidase, did not potentiate the cytotoxic action of oxazaphosphorines toward CFU-S. Cellular NAD-linked aldehyde dehydrogenases are known to catalyze the oxidation of the major transport form of cyclophosphamide, 4-hydroxycyclophosphamide/aldophosphamide, to an inactive metabolite, carboxyphosphamide. Our observations suggest that (1) aldehyde dehydrogenase activity is an important determinant of the sensitivity of a cell population to the oxazaphosphorines, (2) CFU-GM lack the relevant aldehyde dehydrogenase activity, and (3) the phenotypic basis for the relative insensitivity of CFU-S to oxazaphosphorines is the aldehyde dehydrogenase activity contained by these cells.

Topics: Acrolein; Aldehyde Dehydrogenase; Animals; Bone Marrow Cells; Cisplatin; Colony-Forming Units Assay; Cyanamide; Cyclophosphamide; Disulfiram; Ditiocarb; Drug Synergism; Granulocytes; Hematopoietic Stem Cells; Male; Melphalan; Mice; Mice, Inbred BALB C; Nitrogen Mustard Compounds; Organophosphorus Compounds; Phosphinic Acids; Phosphoramide Mustards

Logarithmically growing Yoshida sarcoma cells were treated for 1 h with low (2 decades cell kill) or high (more than 6 decades cell kill) doses of alkylating agents. Pulse and chase labelled DNA from treated cells were studied by alkaline sucrose gradient centrifugation. Nitrogen mustard (HN-2), 4-hydroperoxycyclophosphamide (CY-OOH), melphalan (L-PAM) and chlorambucil (CA) had no effect on the elongation rate of newly replicated DNA, both at low and high doses, although per cell the rate of DNA synthesis declined as inferred from the rates of [3H]thymidine incorporation compared to the increase in numbers of S phase cells in the treated populations. It is concluded that these drugs act specifically on the initiation step of the DNA replication, leaving chain elongation undisturbed. At low doses the chemically related sulphur mustard (SM) had also no effect on the maturation of new DNA but at high doses a decreased elongation rate was observed. A transient inhibition of chain growth was observed following treatment with a low dose of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). In contrast, the intercalating agent adriamycin showed a severe but delayed effect resulting in an almost complete block of the maturation.

Topics: Alkylating Agents; Animals; Carmustine; Cell Division; Cell Survival; Chlorambucil; Cyclophosphamide; DNA Replication; Doxorubicin; Kinetics; Mechlorethamine; Melphalan; Mice; Sarcoma, Yoshida; Structure-Activity Relationship