Impaired angiogenic balance and suppression of tumorigenicity in HeLa cells chronically exposed to interferon-alpha.
We have previously reported that IFNalpha-chronic treatment for 41 days induced a partial phenotype reversion on HeLa cells along with a down-regulation of HPV18 mRNA levels. However, tumorigenicity of these cells in nude mice was unchanged. Interestingly, after 1 year of IFNalpha-chronic exposition, HeLa cells failed to induce s.c. tumors when injected into nude mice. In such experimental conditions both HPV18 DNA integration pattern and viral DNA copy number present in HeLa cells remained intact in the nontumorigenic phenotype cells. As result of the treatment with IFNalpha, HeLa cells rendered more resistant to lysis mediated by activated natural killer cells in vitro. Furthermore, IFNalpha-chronic treatment was able to induce VEGF and decrease bFGF mRNA expression, suggesting a potential effect on the angiogenic behavior of these tumoral cells. Thus, long-term treatment of HeLa cells with IFNalpha can accomplish a reversion of the malignant phenotype by a sequential multistep mechanism, in which the antiangiogenic effect of IFNalpha could be one of the contributing events.
López-Ocejo
O
O
Division of Vaccine, Center for Genetic Engineering and Biotechnology, C. Havana, Cuba.
Perea
S E
SE
Bequet-Romero
M
M
Araña
M J
MJ
López Saura
P
P
D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation; D016228:Endothelial Growth Factors / Q000096:biosynthesis; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis; D018628:Gene Dosage; D006367:HeLa Cells; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000378:metabolism; D008222:Lymphokines / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic; D027383:Papillomaviridae / Q000737:chemistry / Q000378:metabolism; D010641:Phenotype; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D008222:Lymphokines; D012333:RNA, Messenger; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D016222:Fibroblast Growth Factor 2