|Budget Amount *help
¥2,500,000 (Direct Cost : ¥2,500,000)
Fiscal Year 1996 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1995 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Effect of antisense oligo nucleotides complementary to HPV E6/E7 gene. Cervical cancer is associated with expression of Human Papilloma Virus (HPV) E6/E7. We investigated the effect of antisense oligo DNA targeted to E6/E7 gene (AS) in cervical cancer cells (SiHa, C4II,C33a) and immortalized Normal Human Epidermal Karatinocyto (PHK16) by introduction of HPV type 16 genome. Further more, We attempted to evaluate the effect of psolaren conjugated AS (PS-AS) which could form complex formation with targeted sequence more tightly than AS.
1.Proliferation of HPV positive cells (SiHa, C4II,PHK16) was repressed by addition of 5mM AS into the culture medium, except SiHa. Expression of HPVE7 protein was reduced in PHK16 cells but not affected in SiHa cells by addition of AS.These results indicated that AS could suppress cell proliferation by repressing the expression of targeted protein (E7) in HPV positive cells. FITC labeled AS was incorporated into almost all cells, in PHK 16 and SiHa, suggesting that insufficient binding of AS to target sequence might cause ineffectiveness of AS in SiHa cell. Thus, we next attempted to use PS-AS to improve the function of AS.
2.Psolaren (PS) could form cross-link to nucleic acid under long wave UV irradiation. We investigated the effect of PS-AS on cell proliferation. Low dose PS-AS (0.5mM) addition could suppress cell growth in SiHa. However, PS-AS was effective in C33A cell which was HPV negative, suggesting the possibility that toxicity of psolaren but not specific activity of AS could induce growth suppression. As a result, PS-AS might be not useful for clinical application, without protection of cytotoxicity of psolaren.