%0 Journal Article %T Screening and Identification of Peptides Specifically Targeted to Gastric Cancer Cells from a Phage Display Peptide Library %J Asian Pacific Journal of Cancer Prevention %I West Asia Organization for Cancer Prevention (WAOCP), APOCP's West Asia Chapter. %Z 1513-7368 %A Sahin, Deniz %A Taflan, Sevket Onur %A Yartas, Gizem %A Ashktorab, Hassan %A Smoot, Duane T %D 2018 %\ 04/01/2018 %V 19 %N 4 %P 927-932 %! Screening and Identification of Peptides Specifically Targeted to Gastric Cancer Cells from a Phage Display Peptide Library %K Gastric cancer %K phage display %K targeted approach %K subtraction biopanning %R 10.22034/APJCP.2018.19.4.927 %X Background: Gastric cancer is the second most common cancer among the malign cancer types. Inefficiency oftraditional techniques both in diagnosis and therapy of the disease makes the development of alternative and noveltechniques indispensable. As an alternative to traditional methods, tumor specific targeting small peptides can be usedto increase the efficiency of the treatment and reduce the side effects related to traditional techniques. The aim of thisstudy is screening and identification of individual peptides specifically targeted to human gastric cancer cells usinga phage-displayed peptide library and designing specific peptide sequences by using experimentally-eluted peptidesequences. Methods: Here, MKN-45 human gastric cancer cells and HFE-145 human normal gastric epithelial cellswere used as the target and control cells, respectively. 5 rounds of biopannning with a phage display 12-peptide librarywere applied following subtraction biopanning with HFE-145 control cells. The selected phage clones were establishedby enzyme-linked immunosorbent assay and immunofluorescence detection. We first obtain random phage clonesafter five biopanning rounds, determine the binding levels of each individual clone. Then, we analyze the frequenciesof each amino acid in best binding clones to determine positively overexpressed amino acids for designing novelpeptide sequences. Results: DE532 (VETSQYFRGTLS) phage clone was screened positive, showing specific bindingon MKN-45 gastric cancer cells. DE-Obs (HNDLFPSWYHNY) peptide, which was designed by using amino acidfrequencies of experimentally selected peptides in the 5th round of biopanning, showed specific binding in MKN-45cells. Conclusion: Selection and characterization of individual clones may give us specifically binding peptides, butmore importantly, data extracted from eluted phage clones may be used to design theoretical peptides with betterbinding properties than even experimentally selected ones. Both peptides, experimental and designed, may be potentialcandidates to be developed as useful diagnostic or therapeutic ligand molecules in gastric cancer research. %U https://journal.waocp.org/article_58429_19b4625f614b24c1462931540e48253e.pdf