Aplidin, a marine organism-derived compound with potent antimyeloma activity in vitro and in vivo.

Despite recent progress in its treatment, multiple myeloma (MM) remains incurable, thus necessitating identification of novel anti-MM agents. We report that the marine-derived cyclodepsipeptide Aplidin exhibits, at clinically achievable concentrations, potent in vitro activity against primary MM tumor cells and a broad spectrum of human MM cell lines, including cells resistant to conventional (e.g.

Development of a liquid chromatography/tandem mass spectrometry assay for the quantification of PM02734, a novel antineoplastic agent, in dog plasma.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay was developed and validated to quantify a novel antineoplastic agent, PM02734, in dog plasma. The method was validated to demonstrate the specificity, limit of quantification (LOQ), accuracy, and precision of measurements. The calibration range for PM02734 was established using PM02734 standards from 0.

Quantitative analysis of Variolin analog (PM01218) in mouse and rat plasma by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry.

PM01218 is a novel marine-derived alkaloid and has shown potent growth inhibitory activity against several human cancer cell lines. A rapid and sensitive high performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) method was developed and validated to quantify PM01218 in mouse and rat plasma. The lower limit of quantitation (LLOQ) was 0.

Induction of resistance to Aplidin in a human ovarian cancer cell line related to MDR expression.

Aplidin-resistant IGROV-1/APL cells were derived from the human ovarian cancer IGROV-1 cell line by exposing the cells to increasing concentration of Aplidin for eight months, starting from a concentration of 10 nM to a final concentration of 4 microM. IGROV-1/APL cell line possesses five fold relative resistance to Aplidin. IGROV-1/APL resistant cell line shows the typical MDR phenotype: (1) increased expression of membrane-associated P-glycoprotein, (2) cross-resistance to drugs like etoposide, doxorubicin, vinblastine, vincristine, taxol, colchicin and the novel anticancer drug Yondelis (ET-743).

Combination of trabectedin and irinotecan is highly effective in a human rhabdomyosarcoma xenograft.

Our objective was to evaluate in vitro and in vivo the effect of the combination of trabectedin (Yondelis, ET-743) and irinotecan (CPT-11) or its major metabolite SN-38 in a human rhabdomyosarcoma cell line. The schedule trabectedin (1 h) followed by irinotecan or SN-38 (24 h) and the opposite sequence (irinotecan or SN-38 24 h followed by trabectedin 1 h) were analyzed in a rhabdomyosarcoma cell line. In vivo studies were conducted with trabectedin and irinotecan at the doses of 0.

Development of a liquid chromatography/tandem mass spectrometry assay for the quantification of PM00104, a novel antineoplastic agent, in mouse, rat, dog, and human plasma.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay was developed and validated to quantify a novel antineoplastic agent, PM00104, in mouse, rat, dog, and human plasma. The method was validated to demonstrate the specificity, limit of quantification (LOQ), accuracy, and precision of measurements. The calibration range for PM00104 was established using PM00104 standards from 0.

Use of CFU-GM assay for prediction of human maximum tolerated dose of a new antitumoral drug: Yondelis (ET-743).

Acute cytotoxic exposure causes decreases in bone marrow progenitors that precedes the neutrophil nadir. Experiments in animal models reveal a relationship between the reduction in granulocyte-macrophage progenitors (CFU-GM) and the decrease in absolute neutrophil count [Toxicol. Pathol.

In vitro toxicity of three new antitumoral drugs (trabectedin, aplidin, and kahalalide F) on hematopoietic progenitors and stem cells.

Objective: In addition to neutropenias and/or thrombocytopenias as a short-term effect, antineoplastics also can produce long-term effects as a consequence of damage to the hematopoietic stem cells. The aim of the present study was to evaluate the toxicity of three marine-derived antineoplastics on murine hematopoietic stem cells. These antitumoral compounds currently are being evaluated in patients in phase II (aplidin and kahalalide F) and phase II/III (trabectedin) clinical trials.

Validation of a sensitive assay for thiocoraline in mouse plasma using liquid chromatography-tandem mass spectrometry.

A sensitive high-performance liquid chromatography-tandem mass spectrometry assay for thiocoraline, an anti-tumor depsipeptide, in mouse plasma is described. Echinomycin, a quinoxaline peptide, was used as an internal standard. Thiocoraline was recovered from the mouse plasma using protein precipitation with acetonitrile and followed by solid-phase extraction of the supernatant.

Development of a liquid chromatography/tandem mass spectrometry assay for the quantification of Aplidin, a novel marine-derived antineoplastic agent, in human plasma.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay was developed and validated to quantify a novel marine-derived depsipeptide, Aplidin, in human plasma. The method was validated to demonstrate the specificity, recovery, limit of quantitation (LOQ), accuracy, and precision of measurements. The calibration range for Aplidin was established using Aplidin standards from 0.

Effective combination of ET-743 and doxorubicin in sarcoma: preclinical studies.

Purpose: To investigate the cytotoxic and antitumor effects of the combination of the novel anticancer drug ET-743 and doxorubicin (Dx) and to determine whether any pharmacokinetic interaction occurs in sarcoma-bearing mice.

Methods: The cytotoxicity of each drug and of their combinations was assessed in the rhabdomyosarcoma cell line TE-671 by a clonogenic assay, and isobologram analysis was performed to detect any synergistic, additive or antagonistic effects. The antitumor activities of each drug and of the combinations were also evaluated in nude mice transplanted subcutaneously with human TE-671 rhabdomyosarcoma and in C3H female mice injected intravenously with UV2237 M fibrosarcoma or with the Dx-resistant subline UV2237 M-ADM which overexpresses Pgp.

Antiangiogenesis treatment combined with chemotherapy produces chondrosarcoma necrosis.

A combination therapy protocol using a marine chemotherapeutic and an antiangiogenic molecule was tested in a mouse tumor xenograft model for the ability to curtail the growth of a human chondrosarcoma (CHSA). Ecteinascidin-743 (ET-743), a marine-derived chemotherapeutic, was effective at slowing the growth of a primary CHSA. Plasminogen-related protein B, which antagonizes various endothelial cell activities, also elicited a significant inhibition of neoplastic growth, albeit with reduced effectiveness.

Effectiveness of Ecteinascidin-743 against drug-sensitive and -resistant bone tumor cells.

Purpose: The identification of new drugs is strongly needed for bone tumors.Ecteinascidin-743 (ET-743), a highly promising antitumor agent isolated from the marine tunicate Ecteinascidia turbinata, is currently under Phase II clinical investigation in Europe and the United States for treatment of soft tissue sarcoma. In this study, we analyzed the preclinical effectiveness of this drug in osteosarcoma and Ewing's sarcoma.

Preclinical toxicity studies of kahalalide F, a new anticancer agent: single and multiple dosing regimens in the rat.

Purpose: Kahalalide F (KF) is a new anticancer agent currently in clinical trials for solid tumors, including prostate cancer. During the preclinical development of this drug, the studies reported here were conducted to determine the acute and multiple dose toxicities of KF when administered intravenously (i.v.

Unique features of the mode of action of ET-743.

This paper describes the current knowledge of the primary mode of action of a natural product, ecteinascidin 743 (ET-743), derived from the marine tunicate Ecteinascidia turbinata. ET-743 was initially selected for preclinical development because of its potent antitumor activity observed against several human solid tumor types. In vitro, the drug is cytotoxic in the nanomolar range, and in the case of some very sensitive cell lines, in the picomolar range.

A nondisposable microplate for use with organic solvents.

A nondisposable, or "hard", multiwell microplate is described for use with small volumes of biological solutions containing organic solvents. The design of this teflon-coated, aluminum device resembles the 96-well layout of the disposable variety of tissue culture microplates. The reusable, hard microplate has been specifically developed to hold and evaporate volatile organic solvents from aliquots of crude sample extractions or partitions intended for testing in various in vitro biological screening assays.