Yang Liu1,2, Dan Liu3, Chong Wang1,2, Qinyuan Liao1,2, Jing Huang1,2, Dongyang Jiang1,2, Wenwei Shao1,2, Cheng Cameron Yin4, Youhui Zhang5, Gregory Lee6, Xiaoyan Qiu1,2. 1. Department of Immunology, Key Laboratory of Medical Immunology, Ministry of Health, School of Basic Medical Sciences, Peking University, Beijing, China. 2. Peking University Center for Human Disease Genomics, Beijing, China. 3. Harbin Medical University Cancer Hospital, Harbin, China. 4. Department of Hematopathology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA. 5. Department of Immunology, Cancer Institute and Hospital, Chinese Academy of Medical Science, Beijing, China. 6. Andrology Laboratory, University of British Columbia Centre for Reproductive Health, Vancouver, BC, Canada.
Abstract
AIMS: Cancer cell-derived immunoglobulin (Ig)G (cancer-IgG) has been found to be involved in the pathogenesis and progression of many cancers, including lung cancer. The aim of the present study was to investigate the relationship between cancer-IgG expression in lung adenocarcinoma (ADC) and clinicopathological characteristics and clinical outcome. METHODS AND RESULTS: Immunohistochemical analysis was performed using an RP215 monoclonal antibody to determine cancer-IgG expression in 140 lung ADC patients. Cell migration and invasion were analysed in A549 cell line after short interfering RNA (siRNA) knockdown of IgG and cell sorting by flow cytometry. Our results show that RP215 immunostaining score is correlated significantly with local invasion (P < 0.05) and tumour differentiation (P < 0.05) in ADC. Moreover, RP215 staining was significantly higher in metastatic tumours than in primary tumours (P < 0.0001). The knockdown of IgG resulted in a reduction of cell migration and invasion. In contrast, RP215-positive cells displayed greater migration and invasion ability than RP215-negative cells. Additionally, a higher RP215 immunostaining score was associated significantly with poor prognosis. CONCLUSIONS: RP215 staining is correlated strongly with differentiation, local invasion, metastasis and clinical outcome of patients with lung ADC. Our results suggest that RP215 can serve as a biomarker for prognosis of lung ADC.
AIMS: Cancer cell-derived immunoglobulin (Ig)G (cancer-IgG) has been found to be involved in the pathogenesis and progression of many cancers, including lung cancer. The aim of the present study was to investigate the relationship between cancer-IgG expression in lung adenocarcinoma (ADC) and clinicopathological characteristics and clinical outcome. METHODS AND RESULTS: Immunohistochemical analysis was performed using an RP215 monoclonal antibody to determine cancer-IgG expression in 140 lung ADC patients. Cell migration and invasion were analysed in A549 cell line after short interfering RNA (siRNA) knockdown of IgG and cell sorting by flow cytometry. Our results show that RP215 immunostaining score is correlated significantly with local invasion (P < 0.05) and tumour differentiation (P < 0.05) in ADC. Moreover, RP215 staining was significantly higher in metastatic tumours than in primary tumours (P < 0.0001). The knockdown of IgG resulted in a reduction of cell migration and invasion. In contrast, RP215-positive cells displayed greater migration and invasion ability than RP215-negative cells. Additionally, a higher RP215 immunostaining score was associated significantly with poor prognosis. CONCLUSIONS: RP215 staining is correlated strongly with differentiation, local invasion, metastasis and clinical outcome of patients with lung ADC. Our results suggest that RP215 can serve as a biomarker for prognosis of lung ADC.