Glycogene expression profiles based on microarray data of cervical carcinoma HeLa cells partially silenced in E6 and E7 HPV oncogenes

Aberrant glycosylation is a characteristic of tumor cells. The expression of certain glycan structures has been associated with poor prognosis. In cervical carcinoma has been reported changes in the gene expression level of some glycogenes that has been associated with lymph invasion. Human papilloma virus (HPV) infection is one of the most important factors to develop cervical cancer. HPV oncoproteins E6 and E7 have been implicated in cervical carcinogenesis. The role of these oncoproteins in glycosylation changes has not been reported. To know the effect of these oncoproteins on glycogene expression we realized a partial silencing of oncogenes E6 and E7 in HeLa cells, we made a microarray expression assay and we identified glycogenes that modified its expression. The analysis showed alteration in some glycosylation pathways, like glycosphingolipid, O-glycan mucin-type, and O-glycan non mucin-type glycosylation. Our results suggest that E6 and E7 oncoproteins could modified glycosylation of structures implicated in proliferation, adhesion, and apoptosis. Two-condition experiment, HeLa cell groups (shE6/E7, and shControl) One replicate array. 10 µg of total RNA were used for cDNA synthesis incorporating dUTP-Alexa555 (for shE6/E7) or dUTP-Alexa647 (for shControl) employing the First-Strand cDNA labeling kit (Invitrogen). Incorporation of fluorophore was analyzed by using the absorbance at 555 nm for Alexa555 and 650 nm for Alexa647. Equal quantities of labeled cDNA were hybridized using hybridization solution UniHyb (TeleChem International INC). The arrays were incubated for 14 h at 42°C, and then washed tree times with 1X SCC, 0.05 % SDS at room temperature.