ORIGINAL ARTICLES   

The Quarterly Journal of Nuclear Medicine 2003 June;47(2):139-44

Copyright © 2009 EDIZIONI MINERVA MEDICA

language: English

Radioimmuno targetting technetium 99mlabeled anti-epidermal growth factor receptor monoclonal antibody in experimental tumor models

Meenakshi A., Ganesh V., Suresh Kumar R., Siva Kumar N.

Department of Biochemical Oncology Cancer Institute (WIA) Regional Center for Cancer Research and Treatment of Government of India Adyar, Chennai, India

Aim. Monoclonal anti­bod­ies (MAb) direct­ed at the ­extra cel­lu­lar ­domain (ECD) of epi­der­mal ­growth fac­tor recep­tor (­EGFR) ­offer a prom­is­ing strat­e­gy for diag­no­sis and ther­a­py of can­cers ­that ­over-­express ­EGFR. Radiolabelled MAbs ­against ­cell sur­face anti­gens ­have ­improved in ­vivo ­tumor diag­no­sis and treat­ment. ­EGFR ­over-expres­sion has ­been report­ed in a ­wide ­range of car­ci­no­mas espe­cial­ly of the ­head and ­neck, ­breast, etc., and is asso­ciat­ed ­with ­poor prog­no­sis and resis­tance to ther­a­py. ­CIBCNSH3 is a ­murine MAb gen­er­at­ed to the ECD of ­EGFR in our labor­a­to­ry and has ­been exten­sive­ly char­ac­ter­ized and has prov­en anti­tu­mor activ­ity. The ­tumor tar­get­ing poten­tial of 99mTc ­labelled ­CIBCNSH3 in an experi­men­tal ­tumor mod­el is dis­cussed in ­this ­paper.
Methods. A431, an epi­der­moid car­ci­no­ma ­cell ­line ­with over­ex­pres­sion of ­EGFR, SUDHLH, a lymphoma cell line was ­used to ­induce xen­o­grafts in inbred adult female BALB/C mice and ­used for the ­study. A reduc­tion medi­at­ed meth­od of 99mTc label­ling was adopt­ed to ­label the MAb. Scintiscan pic­tures ­were tak­en at dif­fer­ent ­time inter­vals ­after i.v. admin­is­tra­tion of the 99mTc ­labelled MAb ­using a gamma cam­e­ra and ­results ­were cor­re­lat­ed ­with ­those of bio­dis­trib­u­tion stud­ies.
Results. Immunoscan pic­tures tak­en at dif­fer­ent ­time peri­ods ­showed ­high ­uptake of the radio­im­mu­no­con­ju­gate by the ­tumor pro­vid­ing ­clear ­tumor imag­es and no ­uptake in con­trol ani­mals ­with lym­pho­ma xen­o­grafts. Results of ­scan pic­tures cor­re­lat­ed ­well ­with the bio­dis­trib­u­tion stud­ies.
Conclusion. The radio­im­mu­no­con­ju­gate 99mTc-­CIBCNSH3 ­appears to be a prom­is­ing ­tool in iden­ti­fy­ing any ear­ly recur­rence and ­micro-metas­ta­sis of ­lesions ­that over­ex­press ­EGFR.