Effective suppression of the Kirsten rat sarcoma viral oncogene in pancreatic tumor cells via targeted small interfering RNA delivery using nanoparticles.
OBJECTIVE
The objective of this study was to establish an efficient carrier for small interfering RNA (siRNA) delivery targeting pancreatic tumor cells.


METHODS
A copolymer consisting of a single-chain variable fragment targeted to human CD44 variant 6 (scFv(CD44v6)) functional group conjugated to polyethylene glycol-poly-L-lysine was synthesized and assembled into micelles encapsulating the siRNAs. Flow cytometry and Western blot assays were performed to evaluate the transfection efficiency and gene-silencing effect of the siRNAs. Afterward, (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, Transwell, soft agar colony formation, and enzyme-linked immunosorbent assays were performed to evaluate the biological functions of PANC-1 cells after Kirsten rat sarcoma viral oncogene knockdown. In vivo assays were performed using a BALB/c (nu/nu) mouse model subcutaneously injected with PANC-1 xenografts. Real-time in vivo fluorescence imaging was used to monitor the tumor homing of the nanoparticles.


RESULTS
The scFv(CD44v6) enabled more efficient delivery of siRNAs and exhibited enhanced gene silencing compared with nontargeted nanoparticles. Furthermore, targeted delivery of the siRNAs induced a potent inhibitory effect on cell proliferation, colony formation, invasion, and vascular endothelial growth factor production. The animal assays revealed that single-chain variable fragment nanoparticles accumulated in the tumor tissue and enhanced the inhibition of tumor growth in vivo.


CONCLUSIONS
The scFv(CD44v6)-conjugated nanocarriers provide a highly efficient and safe platform for systemic gene therapy for pancreatic cancer.
From the *Department of Gastroenterology, The Second Affiliated Hospital of Sun Yat-sen University, Guangzhou; †Department of Oncology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai; ‡PCFM Lab of Ministry of Education, School of Chemistry; Chemical Engineering, Sun Yat-sen University, Guangzhou; §Henan Eye Institute, Henan Eye Hospital, Zhengzhou; ∥Department of Gastroenterology, Lihuili Hospital of Ningbo Medical Center, Ningbo; ¶Department of Cardiology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai; and #State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou, China.
Linjuan
L
Zeng
Jingguo
J
Li
Jiajia
J
Li
Qiubo
Q
Zhang
Chenchen
C
Qian
Wei
W
Wu
Zhong
Z
Lin
Jianzhong
J
Liang
Yinting
Y
Chen
Kaihong
K
Huang
D000818:Animals; D002465:Cell Movement; D049109:Cell Proliferation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D018960:Hyaluronan Receptors / Q000276:immunology / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000737:chemistry; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008823:Micelles; D050997:Nanomedicine; D053758:Nanoparticles; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D011092:Polyethylene Glycols / Q000737:chemistry; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D016283:Proto-Oncogene Proteins p21(ras); D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D057127:Single-Chain Antibodies / Q000378:metabolism; D013997:Time Factors; D014162:Transfection / Q000379:methods*; D047368:Tumor Burden; D020298:U937 Cells; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays; D018631:ras Proteins / Q000235:genetics* / Q000378:metabolism
C497483:CD44 protein, human; D018960:Hyaluronan Receptors; C117307:KRAS protein, human; D008823:Micelles; D011518:Proto-Oncogene Proteins; D034741:RNA, Small Interfering; D057127:Single-Chain Antibodies; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C092361:poly(ethylene glycol) lysine copolymer; D011092:Polyethylene Glycols; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D008239:Lysine