Chemosensitivity of conjunctival melanoma cell lines to target-specific chemotherapeutic agents.

OBJECTIVE: In conjunctival melanoma, local chemotherapy has been based so far on clinical evidence and limited to the therapy of melanoma in situ. Our aim was to define substances that may have the potential to add to therapeutic options in extended local growth and metastatic disease. Two conjunctival cell lines (CRMM-1 and CRMM-2) have been established from recurrent conjunctival melanoma. In this study, we examined the chemosensitivity of these cell lines to different cytotoxic substances. MATERIALS AND METHODS: The cell lines CRMM-1 and CRMM-2 were exposed to chemotherapeutics for 24 h and the IC50 was generated. Sulforhodamin-B assays were used for quantification of in vitro efficacy. Time of exposure and escalating concentrations of the substances were adapted to the experimental setting. RESULTS: Bortezomib, clusianone 502 (nemorosone), ranpirnase, and sorafenib were efficient in inhibiting the growth of conjunctival melanoma cell lines. The IC50 achieved concentrations below or around 10 µM for these substances. CONCLUSIONS: Bortezomib, clusianone 502, ranpirnase, and sorafenib inhibited growth in conjunctival melanoma cell lines efficiently. The new substances may be a suitable alternative for local therapy. New therapeutic options with highly specific targeted agents for metastatic disease have to be evaluated in further experiments.

Results of a phase I trial of sorafenib (BAY 43-9006) in combination with oxaliplatin in patients with refractory solid tumors, including colorectal cancer.

BACKGROUND: Sorafenib (BAY 43-9006), a multiple kinase inhibitor, has been shown to inhibit tumor growth and tumor angiogenesis by targeting Raf kinase, vascular endothelial growth factor receptor, and platelet-derived growth factor receptor. In phase I studies, sorafenib demonstrated single-agent activity in patients with advanced solid tumors and was successfully combined with oxaliplatin in preclinical studies. This phase I study investigated the safety, pharmacokinetics, and efficacy of sorafenib in combination with oxaliplatin. PATIENTS AND METHODS: Twenty-seven patients with refractory solid tumors were enrolled in the initial dose-escalation part (cohorts 1, 2A, and 2B) and 10 additional patients with oxaliplatin-refractory colorectal cancer were subsequently enrolled in an extension part (cohort 3). Oxaliplatin 130 mg/m2 was given on day 1 of a 3-week cycle and oral sorafenib was administered continuously from day 4 of cycle 1 at 200 mg twice daily (cohort 1) or 400 mg twice daily (cohorts 2A, 2B, and 3). RESULTS: Adverse events were generally mild to moderate and the maximum tolerated dose was not reached. Common adverse events were diarrhea (52% of patients in the dose-escalation part and 20% in the extension part), sensory neuropathy (44% and 20%), and dermatologic toxicities (41% and 80%). No pharmacokinetic interaction between sorafenib and oxaliplatin was detectable. Two patients with gastric cancer had a partial response. Forty-three percent of patients in cohorts 1 and 2A/B and 78% of patients in cohort 3 exhibited stable disease for >or=10 weeks. CONCLUSION: Continuous oral sorafenib 400 mg twice daily was safely combined with oxaliplatin without detectable drug interactions and showed preliminary antitumor activity in this phase I study. This dose is recommended for phase II studies.

Pegylated liposomal doxorubicin: proof of principle using preclinical animal models and pharmacokinetic studies.

Encapsulation of doxorubicin in polyethylene glycol-coated liposomes (Doxil/Caelyx [PLD]), was developed to enhance the safety and efficacy of conventional doxorubicin. The liposomes alter pharmacologic and pharmacokinetic parameters of conventional doxorubicin so that drug delivery to the tumor is enhanced while toxicity normally associated with conventional doxorubicin is decreased. In animals and humans, pharmacokinetic advantages of PLD include an increased area under the plasma concentration-time curve, longer distribution half-life, smaller volume of distribution, and reduced clearance. In preclinical models, PLD produced remission and cure against many cancers including tumors of the breast, lung, ovaries, prostate, colon, bladder, and pancreas, as well as lymphoma, sarcoma, and myeloma. It was also found to be effective as adjuvant therapy. In addition, it was found to cross the blood-brain barrier and induce remission in tumors of the central nervous system. Increased potency over conventional doxorubicin was observed and, in contrast to conventional doxorubicin, PLD was equally effective against low- and high-growth fraction tumors. The combination of PLD with vincristine or trastuzumab resulted in additive effects and possible synergy. PLD appeared to overcome multidrug resistance, possibly as the result of increased intracellular concentrations and an interaction between the liposome and P-glycoprotein function. On the basis of pharmacokinetic and preclinical studies, PLD, either alone or as part of combination therapy, has potential applications to treat a variety of cancers.