| Colon cancer continues to be one of the most common cancers, and the importance and necessity of new
therapies needs to be stressed. The most important proto-oncogen factors for colon cancer appear to be
epidermal growth factor receptor, EGFR, and c-Src with high expression and activity leading to tumor growth
and ultimately to colon cancer progression. Application of c-Src and EGFR antisense agents simultaneously
should theoretically therefore have major benefit. In the present study, anti-EGFR and c-Src specific antisense
oligodeoxynucleotides were combined in a formulation using PAMAM dendrimers as a carrier. Nano drug entry
into cells was confirmed by flow cytometry and fluorescence microscopy imaging and real time PCR showed gene
expression of c-Src and EGFR, as well as downstream STAT5 and MAPK-1 with the tumor suppressor gene
P53 to all be downregulated. EGFR and c-Src protein expression was also reduced when assessed by western
blotting techniques. The effect of the antisense oligonucleotide on HT29 cell proliferation was determined by
MTT assay, reduction beijng observed after 48 hours. In summary, nano-drug, anti-EGFR and c-Src specific
antisense oligodeoxynucleotides were effectively transferred into HT-29 cells and inhibited gene expression in
target cells. Based on the results of this study it appears that the use of antisense EGFR and c-Src simultaneously
might have a significant effect on colon cancer growth by down regulation of EGFR and its downstream genes. |