Treatment of malignant melanoma

Complete regression and systemic protective immune responses obtained in B16 melanomas after treatment with LTX-315

Malignant melanoma is the most aggressive and deadliest form of skin cancer due to its highly metastatic potential, which calls for new and improved therapies. Cationic antimicrobial peptides (CAPs) are naturally occurring molecules found in most species, in which they play a significant role in the first line of defense against pathogens, and several CAPs have shown promising potential as novel anticancer agents. Structure-activity relationship studies on the CAP bovine lactoferricin allowed us to de novo design short chemically modified lytic anticancer peptides. In the present study, we investigated the in vivo antitumor effects of LTX-315 against intradermally established B16 melanomas in syngeneic mice. Intratumoral administration of LTX-315 resulted in tumor necrosis and the infiltration of immune cells into the tumor parenchyma followed by complete regression of the tumor in the majority of the animals. LTX-315 induced the release of danger-associated molecular pattern molecules such as the high mobility group box-1 protein in vitro and the subsequent upregulation of proinflammatory cytokines such as interleukin (IL) 1β, IL6 and IL18 in vivo. Animals cured by LTX-315 treatment were protected against a re-challenge with live B16 tumor cells both intradermally and intravenously. Together, our data indicate that intratumoral treatment with LTX-315 can provide local tumor control followed by protective immune responses and has potential as a new immunotherapeutic agent.

Clinical features of malignant melanoma of the finger and therapeutic efficacies of different treatments

The purpose of this study was to explore the clinical features of malignant melanoma of the finger and therapeutic efficacies of different treatments. The clinical data of 22 patients with malignant melanoma of the finger (confirmed by pathological examination), admitted and treated in our hospital between February 1995 and October 2007, were analyzed retrospectively. The primary site of the tumor was the thumb in 12 cases, index finger in 3 cases, middle finger in 3 cases, ring finger in 2 cases and little finger in 2 cases. The most common presenting symptoms were pain and black patches on the fingers. A total of 15 of the 22 patients had subungual disease, 12 had a history of trauma and 2 had osteolytic bone lesions of the phalanx. The main treatments employed were surgery, chemotherapy and immunotherapy. Finger amputation was performed for all 22 patients and axillary lymph node dissection in the same side was performed for 13 patients. Nineteen cases were followed up for 1-10 years with an average of 5.5 years. Three patients were lost to follow-up 2 years after treatment. The 1-, 3- and 5-year survival rates were 86.4% (19/22), 42.1% (12/19) and 31.2% (6/19), respectively. In conclusion, malignant melanoma of the finger is a rarely occurring tumor. Comprehensive treatment, including surgery, chemotherapy and immunotherapy, is the key approach for malignant melanoma of the finger. Prognosis of the disease is associated with the size of the tumor, depth of infiltration and clinical stages.

Intratumoral injection of DNA encoding human interleukin 12 into patients with metastatic melanoma: clinical efficacy

Plasmid DNA encoding human interleukin 12 (IL-12) was produced under GMP conditions and injected into lesions of nine patients with malignant melanoma (stage IV) previously treated with both standard and nonstandard therapies. The treatment was based on efficacy in preclinical studies with melanoma in mice and gray horses. The DNA was applied in cycles, three injections per cycle, for up to seven cycles. Three therapy arms comprised low (2 mg), medium (4 mg), and high (10 to 20 mg) amounts of total DNA. The therapy was well tolerated. Three of nine patients experienced a clinical response: two stable disease and one complete remission. One patient receiving a low dose of DNA experienced a long-lasting stabilization of the disease for more than 3 years, whereas the other two responders received high doses of DNA. All patients but one (patient 9) experienced a transient response at the intratumoral injection site. Immunohistochemical staining of responder sections showed local reduction of angiogenesis and lymphocyte infiltrations. All patients, in particular the clinical and local responders (patients 3, 7, and 8), exhibited an antigen-specific immune response against MAGE-1 and MART-1, which in some cases preexisted. Biopsies of responders showed some increase in IL-12, IP-10, and IFN-(). Serum levels revealed fluctuations. The results show that intratumoral injection of DNA produced some beneficial clinical effect. DNA encoding a cytokine may be useful as a therapeutic or adjuvant against various human cancers.

Chemotherapy and bio-chemotherapy in patients with advanced melanoma: combination therapy with a nitrosourea

The treatment of advanced melanoma is still disappointing. In a multicenter randomized clinical trial to compare a chemotherapy (CT) with or without low doses of IL-2 and IFN (Bio-CT), the participating centers chose whether or not to add a nitrosourea, carmustine (BCNU) to the therapy. The aim of the present paper is to report the clinical results of the patients (pts) treated in both arms with BCNU. One hundred and seventy-six pts with advanced melanoma were enrolled in the study from 27 centers and a total of 18 pts also received BCNU in 3 centers. No further changes to the protocol criteria were allowed. One patient refused the treatment. No complete responses were observed. Irrespectively of the treatment arm, 9/17 pts showed a partial response to therapy (53%) (5/9 in the CT and 4/8 in the BioCT arm). The most important adverse events observed were hematological: 12 pts presented grade 3 (6 pts) or grade 4 (6 pts) leukocytopenia and 9 pts had grade 4 thrombocytopenia, all of which resolved spontaneously. The addition of a nitrosourea to CT or Bio-CT appears to improve response rates compared to the same regimens without nitrosourea. Patient tolerability is acceptable. Further studies using this combination are warranted.

Microdialysis and response during regional chemotherapy by isolated limb infusion of melphalan for limb malignancies

This study sought to use a microdialysis technique to relate clinical and biochemical responses to the time course of melphalan concentrations in the subcutaneous interstitial space and in tumour tissue (melanoma, malignant fibrous histiocytoma, Merkel cell tumour and osteosarcoma) in patients undergoing regional chemotherapy by Isolated Limb Infusion (ILI). 19 patients undergoing ILI for treatment of various limb malignancies were monitored for intra-operative melphalan concentrations in plasma and, using microdialysis, in subcutaneous and tumour tissues. Peak and mean concentrations of melphalan were significantly higher in plasma than in subcutaneous or tumour microdialysate. There was no significant difference between drug peak and mean concentrations in interstitial and tumour tissue, indicating that there was no preferential uptake of melphalan into the tumours. The time course of melphalan in the microdialysate could be described by a pharmacokinetic model which assumed melphalan distributed from the plasma into the interstitial space. The model also accounted for the vascular dispersion of melphalan in the limb. Tumour response in the whole group to treatment was partial response: 53.8% (n = 7); complete response: 33.3% (n = 5); no response: 6.7% (n = 1). There was a significant association between tumour response and melphalan concentrations measured over time in subcutaneous microdialysate (P< 0.01). No significant relationship existed between the severity of toxic reactions in the limb or peak plasma creatine phosphokinase levels and peak melphalan microdialysate or plasma concentrations. It is concluded that microdialysis is a technique well suited for measuring concentrations of cytotoxic drug during ILI. The possibility of predicting actual concentrations of cytotoxic drug in the limb during ILI using our model opens an opportunity for improved drug dose calculation. The combination of predicting tissue concentrations and monitoring in microdialysate of subcutaneous tissue could help optimise ILI with regard to post-operative limb morbidity and tumour response.

Interferon therapy in primary care

Interferons are proteins produced by human blood cells in response to stimulation (viral infection). The natural roles of interferons are host defense and modulation of the immune system. Therapeutic uses are based on these roles. Interferon-alpha has been widely used for malignancies, skin conditions, viral infections, and myeloproliferative disorders. Interferon-beta is a standard treatment for relapsing multiple sclerosis. Interferon-gamma therapy is currently used for chronic granulomatous disease and skin lesions (human papilloma virus related and keloids), but further research is ongoing. Side effects of interferon therapy are common and limit utility. Flulike symptoms are reported by more than 75% and depression by 10-40% of interferon users. Severe adverse effects are less common but may be life threatening, including autoimmune diseases, thrombotic-thrombocytopenic purpura, and acute renal failure. Limited use of interferon therapy during pregnancy has been described, with successful maternal and neonatal outcomes. Use of interferon therapy during early pregnancy is not an indication for termination.