Screening and Identification of a Targeting Peptide to Hepatocarcinoma from a Phage Display Peptide Library

Abstract

Ligands specific to cell surface receptors have been heavily investigated in cancer research. Phage display technology is a powerful tool in this field and may impact clinical issues including functional diagnosis and targeted drug delivery. In this study, a hepatocellular carcinoma cell line (HepG2) and a normal hepatocyte line (L-02) were used to carry out subtractive screening in vitro with a phage display-7 peptide library. After four rounds of panning, there was an obvious enrichment for the phages specifically binding to the HepG2 cells, and the output/input ratio of phages increased about 976-fold (from 0.3×10 -7 to 292.8×10 -7 ).A group of peptides capable of binding specifically to the hepatoma cells were obtained, and the affinity of these peptides to the targeting cells and tissues was studied. Through a cell-based ELISA, immunocytochemical staining, immunohistochemical staining, and immunofluorescence, the S1 phage and synthetic peptide HCBP1 (sequence FQHPSFI) were shown to bind to the tumor cell surfaces of two hepatoma cell lines and biopsy specimens, but not to normal hepatocytes, other different cancer cells, or nontumor liver tissues. In conclusion, the peptide HCBP1 may be a potential candidate for targeted drug delivery in therapy of hepatoma cancer.

Screening and characterization of novel specific peptides targeting MDA-MB-231 claudin-low breast carcinoma by computer-aided phage display methodologies

“…Tissue sections were blocked using a 5% BSA solution and were incubated at room temperature for 30 min. Immunostaining was performed by adding 100 μL of the last round of the 12-mer phage pool (10 9 PFUs.mL −1 ) to the tissue overnight at 4 °C [24, 25]. Sections were washed 4 times in TBST 1x for 5 min and 100 μL of the primary antibody rabbit anti-fd bacteriophage (working dilution of 1:5000 in BSA 1%), was added and incubated at 4 °C overnight.…”

Liver cell-targeted delivery of therapeutic molecules

“…Homing peptides that specifically target HCC include TTPRDAY (Shimizu et al, 2006), FQHPSFI (HCBP1) (Zhang et al, 2007a), SFSIIHTPILPL (SP94) (Lo et al, 2008), RGWCRPLPKGEG (HC1) (Zhang et al, 2011), AGKGTPSLETTP (A54) (Du et al, 2010), KSLSRHDHIHHH (HCC79) (Jiang et al, 2006) and AWYPLPP (Jia et al, 2007). Several HCC-targeted delivery systems using these peptides have been developed (Du et al, 2010;Lo et al, 2008), but further studies are needed to confirm whether they can distinguish between HCC and hepatocytes or other liver cells.…”

Identification of host cell binding peptide from an overlapping peptide library for inhibition of classical swine fever virus infection

“…Triplicate determinations were performed at each data point. Cell selectivity was determined using the formula [15]: Selectivity = (OD t -ODc)/ODc. Here, OD t and ODc represent the absorbance values from the binding to cells by phage clones and the CT7Ps, respectively.…”