Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants|
|Research Institution||Kochi Medical School|
OSAKI Tokio Kochi Medical School, Department of Oral Surgery, Research Associate, 医学部, 教授 (70031995)
OKU Naohisa Kochi Medical School, Department of Oral Surgery, Research Associate, 医学部附属病院, 助手 (20363286)
UETA Eisaku Kochi Medical School, Department of Oral Surgery, Assistant Professor, 医学部附属病院, 講師 (10203431)
KAMATANI Takaaki Kochi Medical School, Department of Oral Surgery, Research Associate, 医学部附属病院, 助手 (00315003)
SASABE Eri Kochi Medical School, Department of Oral Surgery, Research Associate, 医学部附属病院, 助手 (40363288)
山本 哲也 高知医科大学, 医学部, 助教授 (00200824)
木村 剛 高知医科大学, 医学部附属病院, 助手 (10294836)
|Project Period (FY)
2002 – 2003
Completed(Fiscal Year 2003)
|Budget Amount *help
¥10,400,000 (Direct Cost : ¥10,400,000)
Fiscal Year 2003 : ¥4,700,000 (Direct Cost : ¥4,700,000)
Fiscal Year 2002 : ¥5,700,000 (Direct Cost : ¥5,700,000)
|Keywords||oral cancer / invasion / reactive oxygen species / Mn-SOD / tight junction / occludin / claudin / β-catenin / 活性酵素|
A) We treated oral carcinoma patients by chemo (5-FU and peplomycin)-radio (γ-rays)-immunotherapy (OK-432 and LAK cells) and examined genes and proteins which were associated with the therapeutic effects and lymph node metastasis.
B) Using squamous cell carcinoma (SCC) cell lines established from lymph-metastasized oral SCC, we investigated apoptosis-regulating genes and molecules.
The results are as follows.
A-1. The microarray analysis suggested that the expression of COMT (Catechol-O-methyltransferase) was negatively correlated with lymph node metastasis while C-CAM1 (Carcinoembryonic antigen-related cell adhesion molecule1) was positively correlated with lymph node metastasis and that the expression of MFG-E8 (Milk fat globular-EGF-factor 8) was positively correlated with the effect of chemo-radio immunotherapy.
B-1. The in vitro sensitivity of SCC cell lines to the anticancer agents was inversely correlated with the reactive oxygen species (ROS)-scavenging activity, especially Mn-supe
roxide dismutase (SOD) activity of the cancer cells. The intracellular ROS increased the phosphorylation of the Bcl-2 family proteins and the increased phosphorylation of Bax and Bcl-2 induced a decrease and an increase of their ubiquitination, respectively. Accordingly, these effectsof ROS were inhibited by transfection of Mn-SOD antisense or SCC treatment with antioxidants.
B-2. In SCC cells possessing a highly invasion activity, E-cadherin, one of tight junction structural components, was weakly expressed compared with that in non-ivasive SCC cells, while claudin 1, one of adherens junction components, was strongly expressed in highly invasive SCC cells. The level of E-cadherin expression was inversely correlated with the SCC cell sensitivity to the anticancer agents.
B-3. The expression level of hypoxia inducile factor-1a (HIF-1a) was increased by cultivation of SCC cells in hypoxic condition (1% oxygen) for longer than 12 h or by their treatment with the anticancer agents. The expression level of HIF-1a was negatively correlated with the susceptibility of SCC cells to the anticancer agents. Knockdown of HIF-1a by siRNA induced a high susceptibility to the anticancer agents.
These results indicate that the expression levels of the MFG-E8 gene, E-cadherin, caludin 1 and HIF-1a as well as the ROS scavenging activity are indicative of the susceptibility of SCCs to chemo-radio-immunotherapy and the suggest that the down-regulation of Mn-SOD and HIF-1a is an useful strategy for oral SCC treatment. In addition, regional lymph node metastasis couldbe predicted by the expression pattern of COMT or C-CAM1 gene. Less