Expression And Co-localization Of Hsp70 Grp94 And IgG In Human Lung Carcinoma

Human lung carcinoma is the one of common malignant carcinoma in the world .It has high incidence and mortality rate in our country. The poor understanding to essence and protected mechanism of lung cancer has resulted in treatment failure.A lot of researches have demonstrated that HSPs are rich in all kinds of malignant carcinoma. The expression of HSPs in carcinoma has related with tumor cell proliferation, poor differentiation, lymphatic metastasis and therapy outcome. Materials have found that HSPs could regulate cellular proliferation and cellular atypia differentiation of carcinoma by means of interacting with oncogene, proto-oncogene and their products. Immunoglobulin G (IgG) is the important molecular in immune system. It has been confirmed to be the characteristic product of B lymphocyte. At present, many researches have discovered that human cancers of epithelial origin, including carcinomas of breast, colon, liver, lung and established epithelial cancer lines also produce IgG, but what is the relationship of HSPs and IgG? What are the relationship and their biological functions of HSPs and IgG in neoplasia and its progression? Why tumor cell produce IgG? What is the function of IgG origined tumor? These problems are waiting for further explore in the future.As there is no report about the correlation of HSPs and IgG in human lung cancer, we aim to explore the expression and significance of heat shock protein 70 (HSP70), glucose regulated protein 94 (GRP94) and IgG in human lung carcinoma and their stroma in our study. Firstly, The expression of HSP70, GRP94 and IgG in 40 human lung carcinomas and their stroma was studied using immunohistochemical technique and image analysis.The localization among HSP70 , GRP94 and IgG was analyzed by double labeling immunofluorescent staining and laser scanning confocal microscopy. Secondly, we furtherly confirmed the localization relation through cell culture(A549) using double labeling immunofluorescent staining and laser scanning confocal microscopy methoeds. At last we used RT-PCR to prove that tumor cell could produce IgG. In summary we have found HSP70,GRP94 and IgG in Human lung carcinomas showed high expression. The positive rate of HSP70, GRP94 and IgG was 65% (26/40), 45% (18/40), and 82.5% (33/40), respectively. The average value of optical density was 5.10±0.32, 3.52±0.35, and 8.12±0.31, respectively.HSP70was localized in nucleus and cellular cytoplasm while GRP94 and IgG were mainly localized in cellular cytoplasm. Ten cases showed HSP70 was co-localized with IgG and Eighteen cases showed GRP94 was co-localized with IgG. In stroma we found that GRP94 and IgG have expressed in plasm cells, macrophage and histiocyte. But they are all negative in lymphocyte. We succeed in cloning IgG heavy chain fragment in cell line indicating its genetic origin. So we concluded high expression of HSP70,GRP94 and IgG in human lung carcinomas suggested that HSP70, GRP94 and IgG might play an important role in the development of human lung carcinoma. IgG orgined from tumor cells is co-localized with HSP70 or GRP94. The study will lay a theorical basis for further research on anti-tumor immunotherapy.