Response of primary oral malignant melanoma to interferon: report of two cases

Interferon-gamma and anti-Fas antibody-induced apoptosis in human melanoma cell lines and its relationship to bcl-2 cleavage and bak expression

Interferon-gamma (IFNgamma) has been shown to induce apoptosis through the induction of the Fas antigen in certain cell lines. In this study, we used four melanoma cell lines (MMN9, PMP, MAA and HMG) to study the antiproliferative effect of exogenous IFNgamma treatment, the expression of IFNgamma-induced Fas antigen, and the combined effect of IFNgamma and anti-Fas antibody (CH-11). We also investigated the relationship between Fas-mediated apoptosis and the expression of the bcl-2 family, measured using Western blotting. IFNgamma increased the mean fluorescence intensity of Fas in MMN9 and PMP cells as measured by flow cytometry. Combined therapy had a significant antiproliferative effect on MMN9 and PMP cells, as measured by the MTT assay. After exposure to IFNgamma and anti-Fas antibody, cleavage of bcl-2 occurred in apoptotic cells, and the signal intensity of both bcl-2 and bak decreased in surviving MMN9 cells, as shown by Western blotting analysis. Our results indicate that IFNgamma induces overexpression of Fas and consequently enhances the sensitivity of melanoma cells to Fas-mediated apoptosis. Furthermore, it is possible that cleavage of bcl-2 correlates with the induction of apoptosis induced by IFNgamma and anti-Fas antibody in melanoma cells. We conclude that combined therapy with IFNgamma and anti-Fas antibody may provide an alternative and more efficient chemotherapeutic approach against melanoma cells by inducing the overexpression of Fas after exposure to IFNgamma.

Successful palliation of stenosing anorectal melanoma by intratumoral injections with natural interferon-beta

Anorectal malignant melanoma is an uncommon tumour. Unlike for cutaneous melanoma, there are few guidelines for its optimal management. In particular, very few palliative treatment strategies have been described for patients with advanced disease. We report on an 80 year old patient with locally advanced anorectal melanoma nearly completely blocking the anal orifice and disseminated metastases. Complete regression of the primary tumour and partial remission of the metastases was achieved with intratumoral injections of natural interferon-beta and systemic administration of dacarbazine. The quality of life in this patient was improved markedly by providing relief from severe rectal pain and bleeding. We propose that conservative treatment strategies such as intratumoral injections with interferon-beta should be considered as a palliative treatment option for stenosing anorectal melanoma before an abdominoperineal resection is recommended.

Oral melanoma: diagnosis and treatment

Melanoma of the mouth is rare, most commonly occurring on the upper jaw of patients older than 50 years. Because of a frequent delay in diagnosis, the tumors are often diagnosed after they are deeper than the average cutaneous melanoma. Hence, the prognosis tends to be poor. Surgery is the mainstay of treatment, but often it is difficult because of anatomic restraints. Although melanoma is classically not very radiosensitive, occasional patients have had a good response to radiation therapy, sometimes with temporary palliation. Other treatment modalities are similar to those used for cutaneous melanoma. Immunotherapy, including interferon, has been used. Chemotherapy has a low response rate.

Simultaneous malignant melanoma and squamous cell carcinoma of the oral cavity: a case report

Primary malignant melanoma of the oral cavity is rare. The incidence of oral melanoma constitutes between 0.2% and 8.0% of all melanomas, although higher percentages are reported in Japanese and other nonwhite races. In contrast, squamous cell carcinoma is the most common malignant neoplasm in the oral region. Multiple cancers may develop independently over the course of time in one organ, or double cancers may develop separately in different organs. Both types of cancer are collectively referred to as multiple primary cancers. The simultaneous occurrence of two histologically distinct primary malignancies in the same organ is extremely rare. We present a case of simultaneous malignant melanoma in association with squamous cell carcinoma of the oral cavity.