Non-invasive Diagnosis Of Nasopharyngeal Carcinoma Based On The Raman Spectroscopy

Raman spectroscopy(RS) and surface enhanced Raman spectroscopy technology(SERS) is the hotspot in the field of international biomedical research technique. According to the requirements of clinical diagnosis of nasopharyngeal carcinoma(NPC), in order to explore a quick, objective, non-invasive and accurate diagnosis method based on RS and SERS technique of nasopharyngeal carcinoma, RS and SERS technique with high sensitivity, combined with principle components analysis(PCA) and linear discriminant analysis(LDA) statistics model, were applied to detect the tissue, blood, body fluid of nasopharyngeal carcinoma patients. The main research work includes five parts:1. Discrimination between Early and advanced nasopharyngeal carcinoma tissue based RS detection.Objective: The aim of the study is to evaluate a label-free tissue detection of different stages using Raman spectroscopy(RS).Materials and methods: RS technique were applied to acquire high quality Raman spectra on two tissue groups: one group consists of 30 early stages(I-II) NPC patients, the other group is 46 advanced stages(III-IV) NPC patients. Tentative assignment of Raman bands shows specific biomolecular changes correlated with cancer development. Furthermore, effective diagnostic algorithms based on PCA and LDA were performed for distinguishing Raman spectra of nasopharyngeal tissues from different stages.Result: Nasopharyngeal carcinoma patients with early and advanced tissue have obvious different RS signal. RS combined with PCA and a LDA Yields the sensitivity, specificity and accuracy were 70%, 78.3% and 75% respectively.Conclusion: This exploratory work suggests that RS in conjunction with the PCA-LDA algorithms provides good identification ability of the early and the advanced staged NPC tissues, and it has enormous potential for the non-invasive detection of early and advanced NPC.2. Based on surface enhanced Raman spectroscopy technology to detect nasopharyngeal carcinoma patients saliva directly.Objective: The study evaluates the value of saliva label-free silver nanoparticles SERS in nasopharyngeal carcinoma patients.Materials and methods : 52 saliva samples pathologically proven NPC patients and 60 healthy controls were detected, Ag nanoparticles were synthesized by deoxidizing method, the saliva was compounded with Ag colloids in ratio 1:1, in Via confocal Raman microscope was applied to detect the subjects, the raw spectra needed to be pretreatmented in order to excluded the experimental artifacts, important biochemical SERS spectra bands were tentatively assigned.Result: The saliva SERS spectra contained both healthy volunteers and NPC patients were further probed by multivariate statistical analysis. The key SERS spectra difference between NPC patients and healthy volunteers controls was at 447, 496, 635, 729, 1134, 1270, and 1448 cm-1, which primarily contain signals related to proteins, glycogen, nucleic acids, collagen and fatty acids. Based on PCA and LDA provided a relatively high diagnostic sensitivity of 82.7%, specificity of 91.7%, overall diagnostic accuracy of 87.5%.Conclusion: This study demonstrated that saliva SERS technology combined with PCA-LDA diagnostic algorithms may distinguish NPC from normal healthy volunteers well, the technique for non-destructive diagnosis of nasopharyngeal carcinoma(NPC) has potential clinical application value.3. Detection of plasma label-free SERS in different T stage nasopharyngeal carcinoma.Objective: The aim of study is to evaluate the feasibility of a label-free nanobiosensor based on blood plasma surface-enhanced Raman spectroscopy(SERS) technique for detecting variability of different T stages in nasopharyngeal cancer(NPC).Materials and methods: Au nanoparticles as the SERS-active nanostructures were directly mixed with human blood plasma to enhance the Raman scattering signals. High quality SERS spectra can be acquired from blood plasma samples belong to 60 healthy subjects, 25 T1 stage NPC patients and 75 T2–T4 stage NPC patients.Result: The diagnostic sensitivity is 84% and 92% specificity of 83.3% and 95%, the accuracy is 83.5% and 93.3% respectively, However, between T1 and T2- T4 nasopharyngeal carcinoma, the difference of sensitivity, specificity and accuracy of only 64%, 62.7% and 63%, the degree of differentiation is not ideal, This exploratory study based on SERS nano biotechnology combined with PCA, LDA statistical method can achieve early T1 and healthy volunteers,T2, T4 and the healthy volunteers of the plasma. Difference between early and late is more difficult.Conclusion: So this method can be a potential complement technology used as an early clinical diagnosis of nasopharyngeal carcinoma detection, but there is a great challenge to distinguish the different stage of nasopharyngeal carcinoma.4. Detection of DNA label-free surface enhanced Raman spectroscopy in nasopharyngeal carcinoma patientsObjective: This experiment is to detect the difference between the tissue DNA of nasopharyngeal carcinoma(NPC) and normal nasopharyngeal with the surface enhanced Raman spectroscopy. In order to explore the applied value of surface enhanced Raman spectroscopy in the diagnosis of nasopharyngeal carcinoma.Materials and methods: We detected 91 samples, 26 early stage NPC patients, 35 advanced stage NPC patients and 30 healthy volunteers. There are found significant differences on the DNA of these three kinds of tissue samples Raman spectra, early, late nasopharyngeal carcinoma tissue and normal nasopharyngeal tissue, the spectra of these DNAs can be observed in the following several major spectrum peak: 678,729, 788,1093,1337, 1421,1460,1506,1573cm-1. The raman spectroscopy peak of patients with advanced nasopharyngeal carcinoma tissue samples is stronger than that of early nasopharyngeal carcinoma tissue and normal nasopharyngeal tissue, in 678?788, 1460 cm- 1 the three spectral peak strength. However, in 729,1506 cm- 1 the two spectral peak position shows the Raman spectra of patients in early stage is higher.Result: The experimental exist good repeatability. Furthermore, effective diagnostic algorithms based on PCA and LDA were applied for distinguishing Raman spectra of nasopharyngeal tissues from different stages, acquiring diagnostic sensitivity and specificity of 80.8% and 84.6% respectively, overall discriminant accuracy is 86.8% on early stage, a diagnostic sensitivity of 85.7% and a specificity of 82.1%, overall discriminant accuracy is 92.3% in advanced stage.Conclusion: This exploratory work suggests that SERS in conjunction with the PCA-LDA algorithms provides good identification ability of the early and the advanced stage NPC from DNA, and it has enormous potential for screening for nasopharyngeal carcinoma(NPC).5. Nasopharyngeal tissue in vivo with Nasopharyngeal endoscope Raman spectrum signal detectionObjective: The most commonly useful screening detection methods of nasopharyngeal carcinoma is suspicious lesions histopathologic biopsy,but this approach is easy to result in missed diagnosis and misdiagnosis. To avoid misdiagnosis and missed diagnosis, we explore the feasibility of endoscopic nasopharyngeal cancer nasopharyngeal fiber body Intrapulse Stimulated Raman spectroscopy detection.Materials and methods: This article apply the fluorescence imaging and Raman spectroscopy technology under nasal endoscope in vivo, explore the living fluorescence image and Raman spectra of nasopharyngeal carcinoma(NPC) for nasopharyngeal carcinoma real-time Raman spectroscopy for the first time.Result: For the first time we got the nasopharyngeal carcinoma real-time living Raman spectra.conclusion: The nasopharyngeal microscopically in vivo fluorescence imaging combination Raman spectroscopy has certain potential to improve the effectiveness of the diagnosis of nasopharyngeal carcinoma(NPC).