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T ECHNOLOGY, PRODUCTS, MA RKETS AND SERVICE OPPORTUNITIES A NEW MEDICINE PUBLICATION SEPTEMBER 1995 VOLUME 1, NUMBER 5 Vertex Pharmaceuticals 130 STATE-OF-THE-ART IN THE MANAGEMENT OF CANCER Xenova 130 MALIGNANT MELANOMA Oligonucleotide-based agents/ribozymes 130 Other agents in development 131 ETIOLOGY AND RISK FACTORS 117 Drug Delivery Methodologies Used to PATHOGENESIS, CLASSIFICATION, STAGING Reverse P-gp MDR 132 AND PROGNOSIS 118 Aronex 132 EPIDEMIOLOGY 119 Combination of MDR Modulators in Cancer Therapy 132 DIAGNOSIS 122 Monoclonal Antibodies 133 CURRENT DISEASE MANAGEMENT APPROACHES 123 Ingenex 133 Surgery 124 OVERCOMING OTHER TYPES OF MDR 133 Chemotherapy 125 Overcoming Resistance to Topoisomerase Dacarbazine 125 II Poisons 133 Fotemustine 125 Overcoming Resistance to Free Radical-Mediated Vindesine 125 Drug Cytotoxicity 133 Interferon-α 2b 126 Overcoming Resistance to Alkylating Agents and Platinum Compounds 133 Interferon-α 2a 126 Terrapin Technologies 134 Sequential Chemoimmunotherapy 126 Institute Pasteur 134 Overcoming Resistance to Antimetabolites 134 MEETING COVERAGE Sparta Pharmaceuticals 135 Reversal of Apoptosis-Mediated Chemoresistance 136 19TH INTERNATIONAL CONGRESS OF CHEMOTHERAPY, MONTREAL, QUEBEC, CANADA, JULY 16-21, 1995 NEW TREATMENT APPROACHES FOR INFECTIONS IN STATE-OF-THE-ART IN THE MANAGEMENT OF CANCER NEUTROPENIC PATIENTS 127 Piperacillin/Tazobactam 127 MALIGNANT MELANOMA Recombinant Granulocyte-Colony Stimulating Factor Malignant melanoma is a relatively rare tumor. Combination Therapy 128 Although highly aggressive it is usually curable when treated Meropenem 128 in its early stages. In spite of its low prevalence and limited Pefloxacin with Teicoplanin 128 impact, melanoma has become the object of a dispropor- Ciprofloxacin 128 tionally large research effort because of its immunogenic nature. Melanoma elicits both host humoral and cellular Fluconazole 128 responses, and techniques developed to understand and exploit this phenomena may lead to the discovery of MECHANISMS IN MALIGNANCY immunotherapy strategies to treat this and other cancers exhibiting similar behavior. DRUG RESISTANCE IN CANCER-PART III ETIOLOGY AND RISK FACTORS NOVEL AGENTS IN DEVELOPMENT TO OVERCOMING The etiology of melanoma remains obscure. Risk factors P-GLYCOPROTEIN-MEDIATED RESISTANCE 129 associated with melanoma include hereditary predisposi- Novel Drugs Being Evaluated in P-gp MDR 129 tion, mutations in pivotal genes, occupational and/or envi- Byk Gulden 129 ronmental factors, exposure to ultraviolet (UV) radiation, and various precancerous and cancerous conditions. Risk Cell Therapeutics 129 for development of malignant melanoma has been reported CytRx 129 to be greater in persons of higher socioeconomic status. Knoll Pharmaceuticals 129 According to a study sponsored by the American Cancer COPYRIGHT © 1995 NEW MEDICINE, INC. UNAUTHORIZED PHOTOCOPYING, DISTRIBUTION OR ELECTRONIC STORAGE IS PROHIBITED BY LAW. FUTURE ONCOLOGY SEPTEMBER 1995 VOLUME 1, NUMBER 5 Society, the risk of development of malignant melanoma nevi have been observed to evolve into cutaneous in men was significantly higher in high-paying versus melanoma, the frequency of conversion to melanoma of low-paying occupations (odds ratio = 1.58) and in white- any single nevus is quite low. However, in melanoma- collar versus blue-collar occupations (odds ratio = 1.33). prone families, these cancers are associated with dys- No significant conclusions could be drawn for women. plastic nevi in more than 80% of the cases. Also, giant Interestingly, no significant differences in risk were congenital melanocytic nevi are associated with a greatly observed between those with indoor versus outdoor increased risk of melanoma (approximately 6% lifetime occupations. Among specific occupational exposures, risk of melanoma development). In a study conducted to only exposure to X-rays significantly raised malignant assess the degree of risk associated with such nevi, melanoma risk (odds ratio = 1.37) (Pion IA, etal, Cancer, among 33 patients with a congenital nevus covering at 1995 Jan 15, 75(2 Suppl):637-44). least 5% of body area, two melanomas occurred during Although rising incidence of all skin cancer (basal cell follow-up that were fatal. Patients with nevi 1% to 4% of and squamous cell carcinoma as well as malignant body area did not exhibit increased risk. Lentigo maligna melanoma) among fair-skinned Caucasians in the devel- develop into invasive melanoma with a frequency oped world has been attributed to increased exposure to reported in the literature ranging from 5-50% (Sober AJ ultraviolet (UV) radiation, the connection between such and Burstein JM, Cancer, 1995 Jan 15, 75(2 Suppl):645- exposure and the development of skin cancer has not 50 and Swerdlow AJ, etal, Journal of the American been elucidated. Nevertheless empirical observations Academy of Dermatology, 1995 Apr, 32(4):595-9). indicate that UV exposure is one of the major contributing Patients with a history of basal cell and/or squamous factors. For instance, the risk of contracting cutaneous cell skin cancer are at substantial increased risk for and ocular melanomas is much higher among fair- developing malignant melanoma. Ten of 290 white skinned than dark-skinned individuals, indicating a pro- patients with a history of non-melanoma skin cancer tective effect of melanin against sun exposure. Although but with no personal or family history of malignant it is possible that sunlight exposure is an indirect risk melanoma developed this cancer within an average of factor, (by stimulating growth factor production, which 109 months of follow-up (range, 3-17 years). All cases then stimulates melanocytic proliferation, leading to were less than 0.70 mm in Breslow thickness and 80% melanoma), it is more likely that sunlight effect on occurred on non-exposed sites. The expected number of melanoma is primarily direct. For instance, visceral malignant melanoma in the control population was 0.59, 118 melanomas, an extremely rare form of this cancer, resulting in a relative risk of 17 for those with a history of occured with similar frequency in blacks and whites, as skin cancer (Marghoob AA, etal, Cancer, 1995 Jan 15, was shown in a study of 25,184 visceral melanoma cases 75(2 Suppl):707-14). (Neugut AI, etal, American Journal of Public Health, Retinoblastoma patients (often exhibiting germline 1994 Nov, 84(11):1828-9). mutations in the retinoblastoma tumor suppressor gene) Epidemiologic data suggests that it is the repeated and their relatives also appear to have an increased risk sun tanning and sunburns that place individuals at of other cancers, especially malignant melanoma, which higher risk for malignant malanoma. Exposure to shorter represents 7% of second primaries in retinoblastoma sur- wavelength UVB radiation (280-320 nm in wavelength) vivors. Individuals belonging to families with the atypical is considered the most damaging, although UVA radia- mole syndrome (encountered in families with a genetic tion (320-400 nm in wavelength) may also be harmful. susceptibility to melanoma) have a recognizable pheno- Interestingly, sunscreens are very effective in blocking type, with many atypical melanocytic nevi (Bataille V, UVB but not UVA, leading to the hypothesis that expo- etal, British Journal of Dermatology, 1995 Jan, 132 sure to UVA is the culprit for the rise in the incidence of (1):134-8). Intraocular malignant melanoma is also linked malignant melanoma. to familial atypical multiple mole syndrome. Skin exposure to potentially carcinogenic therapies, such as ionizing radiation or alkylating agents, may also PATHOGENESIS, CLASSIFICATION, STAGING AND give rise to secondary cutaneous malignancies. Six out of PROGNOSIS 164 patients with cutaneous T-cell lymphoma treated by The genesis, evolution and progression of malignant total skin electron beam therapy between 1974 and 1990 melanoma are not fully understood. Although various developed malignant melanoma within 12 to 95 months genetic factors have been linked to melanoma (see of treatment. Three of the six patients had also received Exhibit 1), their role is unclear. Even the role of the gen- oral psoralen with UVA as additional therapy and two erally accepted contributor to melanoma, UV radiation had received topical mechlorethamine (Licata AG, etal, exposure, remains obscure. However, although the pre- Archives of Dermatology, 1995 Apr, 131(4):432-5). cise molecular impact of UV radiation in the pathogene- Certain skin lesions are also markers for increased sis of melanoma is not known, UV has been shown to risk. The most important precursor/marker for melanoma alter expression of multiple genes in both melanocytes is the atypical mole or dysplastic nevus which occur in 5- and melanoma cells, some of which may have a role in 10% of the USA population. Although in some cases these the initiation or progression of melanoma (AACR95, Abs. COPYRIGHT © 1995 NEW MEDICINE, INC. 714. 830. 0448. FUTURE ONCOLOGY SEPTEMBER 1995 VOLUME 1, NUMBER 5 Exhibit 1 Various Genetic Markers Associated with Malignant Melanoma Gene/Chromosome Product Comments MAGE gene family Codes for antigens recognized by autologous Not expressed in normal tissues except cytotoxic T lymphocytes (CTL) on melanoma tumors for testis MAGE-1 Melanoma peptide antigen (46 kDa) recognized by cytotoxic T-lymphocytes MAGE-3 BAGE Codes for a putative protein of 43 aa; seems to Like the MAGE genes, it is silent in normal tissues belong to a family of several genes; BAGE is with the exception of