KIMURA Mitsutaka Kyushu Dental College, Faculty of Dentistry, Department of Pediastric Dentistry,, 歯学部, 教授 (70047801)
KAWANO Kenji Oita Medical University, Faculty of Medicine, Department of Oral and Maxillo-Fac, 医学部, 助手 (50214664)
MATSUSHIMA Rintaro Oita Medical University, Faculty of Medicine, Department of Oral and Maxillo-Fac, 医学部, 講師 (10209546)
MIZUKI Harumi Oita Medical University, Faculty of Medicine, Department of Oral and Maxillo-Fac, 医学部, 講師 (40145397)
|Budget Amount *help
¥6,700,000 (Direct Cost : ¥6,700,000)
Fiscal Year 1994 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1993 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1992 : ¥4,700,000 (Direct Cost : ¥4,700,000)
Tumors, especially malignancies, of the oral caivity are treated with surgery, radiation, chemotherapy, or a combination of these modelities. The treatment for any given case depends on several factors, including the histopathological diagnosis, the location of the tumor, the presence and degree of metastaisis, the radiosensitivity and chemosensitivity of the tumor, and the age and general conditions of the patient. This project was planned to study the in vitro behavior of oral tumors under different culture conditions and decide the degree of malignancy from the aspect of tumor biology. The goal of this project will be to establish a guide for prognosis and treatment of oral tumors.
In this study, two established cancer cell lines (MOK-101 and MOK-102) were used throughout experiments. MOK-101 and MOK-102 were derived from the lingual squamous cell carcinoma of a 53 year-old female and the gingival SCC of a 75 year-old male, respectively. An explant outgrowth culture technique was emp
loyed for the establishment of cell lines. Both carcionomas showed similar histological features ; the poorly differentiated type (WHO,1971), the invasion mode of type 2(Yamamoto-Kohama's classification, 1983) and the intermediate grade of the Anneroth's histologic malignancy grading system (1987). Following in vitro and in vivo methods were used to examine biological features of two cell lines ; simple plate culture, agar suspension culture, collagen gel culture and transplantation in nude mice. MOK-101 and MOK-102 showed 21.0 hours and 29.1 hours in doubling times, 3.01*10^5 cells/cm^2 and 6.67*10^4 cells/cm^2 in confluent cell densities, and 0.008% and 0.023% in colony forming efficiency by agar suspension culture, respectivery. Invasion properties of two cell lines were studied by an in vitro invasion model using collagen-gel culture. Both cell lines migrated into the collagen gel combined with MRC-5 (a fibroblast cell line from human embryo lung tissue), and migration occurred more frequently in MOK-101 than in MOK-102. When Swiss albino 3T3 (a fibroblast cell line from mouse embryo) was incorporated in the collagen gel, MOK-101 showed migration into the gel, but MOK-102 did not. Tumorigenicity in nude mice (BALB/c nu/nu, male, 6 weeks) was examined orthotopically and ectotopically. When transplanted in the muscle of tongue, both cell lines formed nodules. On the other hands, MOK-101 formed a nodule in the dermis of back, but MOK-102 did not. Histologically, MOK-101 revealed an expansive growth in tongue and back, while MOK-102 revealed an invasive growth in tongue. It was noteworthy that, although primary tumors of two cell lines showed similar histological features, there was much difference between biological behaviors of the two under experimental conditions. Further studies are necessary for understanding of results obtained in the present studies.
Furthermore, succinic dehydrogenase inhibition test (SDI test) and colony inhibiton test were carried out to examine sensitivities of two cell lines to several anti-cancer drugs. It was concluded that SDI test gave more constant results that colony inhibition test did. Less