title: Human epithelial cancers secrete immunoglobulin g with unidentified specificity to promote growth and survival of tumor cells.
abstract: Immunoglobulins (Igs) are found thus far only to be produced by differentiated B lymphocytes. By immunohistochemistry analysis, in situ hybridization, and laser capture microdissection-assisted single-cell PCR, we demonstrate that human cancers of epithelial origin, including carcinomas of breast, colon, liver, lung, established epithelial cancer lines, as well as some normal lung tissues, also produce IgG in both cytoplasmic and secreted forms. Furthermore, blockade of tumor-derived IgG by either antisense DNA or antihuman IgG antibody increased programmed cell death and inhibited growth of cancer cells in vitro. More importantly, administration of antihuman IgG antibody also suppressed the growth of an IgG-secreting carcinoma line in immunodeficient nude mice. Our results support a role of tumor-derived IgG as growth factor for epithelial cancers. Prevalent expression of IgG in human carcinomas and its growth-promoting functions may have important implications in growth regulation and targeted therapy of human cancers.
authors.affiliation: Beijing University Center for Human Disease Genomics, 38 Xue-yuan Road, 100083 Beijing, China. qiuxy@bjmu.edu.cn
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Qiu
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhu
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Mao
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Peng
authors.initials: P
authors.lastname: Hao
authors.forename: Guohui
authors.initials: G
authors.lastname: Li
authors.forename: Peng
authors.initials: P
authors.lastname: Lv
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Li
authors.forename: Xin
authors.initials: X
authors.lastname: Sun
authors.forename: Lemeng
authors.initials: L
authors.lastname: Wu
authors.forename: Jie
authors.initials: J
authors.lastname: Zheng
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Deng
authors.forename: Chunmei
authors.initials: C
authors.lastname: Hou
authors.forename: Peixian
authors.initials: P
authors.lastname: Tang
authors.forename: Shuren
authors.initials: S
authors.lastname: Zhang
authors.forename: Youhui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D019073:HT29 Cells; D006367:HeLa Cells; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D016376:Oligonucleotides, Antisense / Q000235:genetics / Q000494:pharmacology; D014183:Transplantation, Heterologous
chemical_list: D007074:Immunoglobulin G; D016376:Oligonucleotides, Antisense