Lectin-immobilized fluorescent nanospheres for targeting to colorectal cancer from a physicochemical perspective.

Abstract

The goal of this research is to develop an imaging agent that enables real-time and accurate diagnosis of small-sized colorectal cancer. Since colorectal cancer initially develops in the mucous membrane of the large intestine, a nonabsorbable colonoscopic imaging agent capable of being administered intracolonically was designed. The imaging agent is peanut agglutinin (PNA)-immobilized polystyrene nanospheres with surface poly(N-vinylacetamide) (PNVA) chains encapsulating coumarin 6. PNA is a targeting moiety that binds to β-D-galactosyl-(1-3)-N-acetyl-D-galactosamine, which is the terminal sugar of the Thomsen-Friedenreich antigen that is specifically expressed on the mucosal side of colorectal cancer cells. PNVA is immobilized with the aim of reducing nonspecific interactions between the imaging agent and normal tissues, because the initial tumor-derived change is very small throughout the entire large intestine. Coumarin 6 is encapsulated into nanosphere cores to provide endoscopically-detectable fluorescence intensity. It is anticipated that the intracolonically-administered imaging agent recognizes tumor-derived changes in the large intestinal mucosa with high affinity and specificity. Real-time and accurate diagnosis of small-sized early colorectal cancer can be achieved through an imaging agent providing clear fluorescence contrast between normal and cancer tissues observed with a florescence endoscope. This review describes the design concept of this nanoprobe from a physicochemical perspective.

• Authors: Shinji Sakuma, Shinji Yamashita, Ken-ichiro Hiwatari, Robert M Hoffman, Wellington Pham
• Journal: Current drug discovery technologies (Curr Drug Discov Technol) Vol. 8 Issue 4 Pg. 367-78 (Dec 01 2011) ISSN: 1875-6220 [Electronic] United Arab Emirates
• PMID: 21644921 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Review)

Chemical References

• Acetamides
• Coumarins
• Fluorescent Dyes
• Peanut Agglutinin
• Polystyrenes
• Polyvinyls
• Thiazoles
• coumarin 6
• poly(N-vinylacetamide)

Topics

• Acetamides (chemistry)
• Animals
• Colonoscopy (methods)
• Colorectal Neoplasms (diagnosis, pathology)
• Coumarins (chemistry)
• Drug Delivery Systems
• Fluorescent Dyes (chemistry)
• Humans
• Nanospheres
• Peanut Agglutinin (chemistry)
• Polystyrenes (chemistry)
• Polyvinyls (chemistry)
• Thiazoles (chemistry)