title: Novel amelanotic and melanotic cell lines NM78-AM and NM78-MM derived from a human oral malignant melanoma.
abstract: Abstract Novel cell lines, designated NM78-AM and NM78-MM, have been established from a malignant melanoma of the cheek oral mucosa. NM78-AM cells were spherical, grew in suspension as clusters, and produced no melanin. In contrast, NM78-MM cells were adherent and produced melanin granules. Initially, NM78-AM cells were grown on fibroblast feeder cells or in growth media supplemented with 10% conditioned medium from fibroblasts, but eventually grew in standard growth media alone. NM78-AM cells had interdigitating microvilli and formed cell clusters. They had large nucleoli, desmosomes, lipid droplets, and well-developed Golgi apparatuses. In contrast, NM78-MM cells grew as adherent neuron-like cells. They had large prominent nucleoli, irregular nuclear membranes, a number of mitochondria, well-developed Golgi apparatuses, melanosomes at various stages of development in the cytoplasm, and the cells secreted melanin granules. Projections from these melanotic cells formed anastomoses with each other. NM78-MM cells stained immunofluorescently for internexin, neuron specific enolase, NF-200, and glial fibrillary acidic protein. These cells were severely aneuploid, approximating to triploidy, and had many marker chromosomes. We used a real-time monitoring system to evaluate oxygen concentrations in culture medium to investigate the susceptibility of both cell lines to various anti-cancer drugs. NM78-AM cells were slightly sensitive to actinomycin D, but not to cisplatin, irinotecan, the irinotecan metabolite SN-38, taxol, taxotere, bleomycin and methotrexate; NM78-MM cells were sensitive to cisplatin, and not to taxol, taxotere, carboplatin, and irinotecan. These new cell lines, NM78-AM and NM78-MM, will be very important for the development of new chemotherapeutics for oral malignant melanoma.
authors.affiliation: Section of Developmental and Regenerative Dentistry, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo, Japan. t.nakahara@tky.ndu.ac.jp
authors.forename: Taka
authors.initials: T
authors.lastname: Nakahara
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Tamaki
authors.forename: Noriko
authors.initials: N
authors.lastname: Tominaga
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Ide
authors.forename: Masanori
authors.initials: M
authors.lastname: Nasu
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ohyama
authors.forename: Soh
authors.initials: S
authors.lastname: Sato
authors.forename: Isamu
authors.initials: I
authors.lastname: Ishiwata
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishikawa
mesh_terms: D000368:Aged; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D002610:Cheek; D003470:Culture Media; D055808:Drug Discovery; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D008297:Male; D008543:Melanins / Q000096:biosynthesis; D008545:Melanoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D051379:Mice; D046529:Microscopy, Electron, Transmission; D009061:Mouth Mucosa; D009062:Mouth Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D009368:Neoplasm Transplantation
chemical_list: D000970:Antineoplastic Agents; D003470:Culture Media; D008543:Melanins