Screening and
Identification of Human Lung
Cancer-related Antigens
LIU Hai-Yan, PENG Liang-Ping, RAN
Yu-Liang, ZHANG Liang-Ze, ZHANG De-Chao, ZHU You-Kang, YANG Zhi-Hua*
( Department of Cellular and Molecular Biology, Cancer Institute, Chinese
Academy of Medical Sciences, Beijing 100021, China )
Abstract One of the
cardinal questions in tumor immunology is the identification of antigenic
structures in human tumors that are recognized by host immune system. A
powerful new methodology for identifying human tumor antigens eliciting humoral
immune response is SEREX (serological identification of antigen by recombinant
cDNA expression cloning). Here, by using this method, a recombinant cDNA
expression library from lung cancer was analysed and several new tumor antigens
were isolated. Using the λ-ZAP vector, cDNA expression library was constructed
from lung cancer tissues of three patients including a moderately
differentiated lung adenocarcinoma, a highly differentiated lung squamous cell
carcinoma and a moderately differentiated lung adeno-squamous carcinoma. The
primary library consisted of 0.8×106 recombinants. 33 positive
clones encoding antigen genes were obtainedafter immunoscreening, and the
nucleotide sequences of cDNA inserts were determined and analysed with DNASIS
and BLAST softwares in EMBL and
GenBank. These antigen genes included known genes, such as MAGE (melanoma
antigen gene), vitiligo-associated protein VIT-1, fibronectin, Na-K-ATPase et al and unknown
genes or ESTs. To characterize expression profile of these genes, antibodies in
sera from 48 lung cancer patients and 48 health donors were assayed with three
antigens (L-8, L-19, L-51) to screen specific and relative serum markers for
lung cancer. The results show that positive rates in lung cancer patients are
higher than in health donors. Our research indicates that some of these
antigens may be related to lung cancer and may be valuable tumor markers in
diagnosis of lung cancer.
Key words lung cancer； tumor antigens； SEREX； cDNA expression library
*Corresponding author:
Tel, 86-10-67781331-8439； Fax, 86-10-67713359; e-mail, [email protected]