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Background: Previous studies have shown that Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is closely associated with the occurrence and development of nasopharyngeal carcinoma, and can be used as a tumor marker in screening for the disease. Here we report a new methodology based on highly specific and sensitive surface-enhanced Raman scattering (SERS) technology to detect LMP1 in nasopharyngeal tissue sections directly with no need of tedious procedures as with conventional immunohistochemistry methods., Methods: LMP1-functionalized 4-mercaptobenzoic acid (4-MBA)-labeled Au/Ag core-shell bimetallic nanoparticles were prepared first and then applied for analyzing LMP1 in formalin-fixed paraffin-embedded nasopharyngeal tissue sections obtained from 34 cancer patients and 20 healthy controls. SERS spectra were acquired from a 25 × 25 spot square area on each tissue section and used to generate SERS images., Results: Data from SERS spectra and images show that this new SERS-based immunoassay detected LMP1 in formalin-fixed paraffin-embedded nasopharyngeal tissue sections with high sensitivity and specificity. The results from the new LMP1-SERS probe method are superior to those of conventional immunohistochemistry staining for LMP1, and in excellent agreement with those of in situ hybridization for EBV-encoded small RNA (EBER)., Conclusion: This new SERS technique has the potential to be developed into a new clinical tool for detection and differential diagnosis of nasopharyngeal carcinoma as well as for predicting metastasis and immune-targeted treatment of nasopharyngeal carcinoma.

Background: Adoptive immunotherapy with EBV-specific CTLs (EBV-CTL) has been used to treat EBV-associated nasopharyngeal carcinoma (NPC) but only a fraction of the patients shows noticeable clinical response., Patients and Methods: Sixty-seven newly diagnosed NPC patients from 2005 to 2007 and 21 healthy donors were collected. Immunological parameters and immune function of PBMCs and EBV-CTL were analyzed by flow cytometer analysis (FACS) and ⁵¹Cr releasing experiment; Molecular characteristics on NPC tumor cells were investigated by immunochemical staining and statistic analysis., Results: NPC patients can be classified into two groups based on the percentage of CD3+ T cells in peripheral blood before accepted any treatment, (>52.6%, mean-2SE from healthy controls, NPC Group 1; <52.6%, NPC Group 2). The patients in Group 2 showed a significant decrease of CD3+CD8+ T-cells, CD3+CD4+ T-cells and CD3+CD45RO+ memory T cells, and increase of CD3⁻CD16+ NK cells compared to Group 1 patients and healthy controls (P<0.001). EBV-specific T cell responses, were weaker in this group of patients and their tumor cells expressed lower levels of the EBV encoded latent membrane protein (LMP)-1 and HLA class II protein compared with the patients of NPC Group 1 (P<0.05)., Conclusion: These findings demonstrate that NPC patients could be distinguished on the basis of their immune status which will affect the efficacy of EBV-CTL immunotherapy.

An important role for B cells and immunoglobulin deposition in the inflammatory tumor cell environment has been recognized in several cancers, and this is recapitulated in our murine model of inflammation-associated carcinogenesis: transgenic mice expressing the Epstein-Barr virus oncogene LMP1 in epithelia. Similarly in several autoimmune disorders, immunoglobulin deposition represents a key underlying event in the disease process. However, the autoantigens in most cases are not known. In other studies, overexpression of the enzymatically inactive mammalian chitinase-like proteins (CLPs) has been observed in a number of autoimmune disorders and numerous cancers, with expression correlated with poor prognosis, although the function of these proteins is largely unknown. We have now linked these observations demonstrating that overexpression of the CLPs renders them the targets for autoantigenicity during carcinogenic progression. We show that the CLPs, Chi3L1, Chi3L3 /YM1, and Chi3L4/YM2, are abundantly overexpressed in the transgenic epidermis at an early, preneoplastic stage and secreted into the serum. Immunoglobulin G reactive to the CLPs is detected in the serum and deposited in the hyperplastic tissue, which goes on to become inflamed and progressively displastic. The CLPs are also upregulated in chemical carcinogen-promoted lesions in both transgenic and wild-type mice. Expression of the related, active chitinases, Chit1 and AMCase, increases following infiltration of inflammatory cells. In this model, the 3 CLPs are autoantigens for the tissue-deposited immunoglobulin, which we propose plays a causative role in promoting the inflammation-associated carcinogenesis. This may reflect their normal, benign function to promote tissue remodeling and to amplify immune responses. Their induction during carcinogenesis and consequent autoantigenicity provides a missing link between the oncogenic event and subsequent inflammation. This study identifies the CLPs as important and novel therapeutic targets to limit inflammation in cancer and potentially also autoimmune disorders.