In-vivo nonlinear optical microscopy (NLOM) of epithelial-connective tissue interface (ECTI) reveals quantitative measures of neoplasia in hamster oral mucosa.

The epithelial-connective tissue interface (ECTI) plays an integral role in epithelial neoplasia, including oral squamous cell carcinoma (OSCC). This interface undergoes significant alterations due to hyperproliferating epithelium that supports the transformation of normal epithelium to precancers and cancer. We present a method based on nonlinear optical microscopy to directly assess the ECTI and quantify dysplastic alterations using a hamster model for oral carcinogenesis. Neoplastic and non-neoplastic normal mucosa were imaged in-vivo by both multiphoton autofluorescence microscopy (MPAM) and second harmonic generation microscopy (SHGM) to obtain cross-sectional reconstructions of the oral epithelium and lamina propria. Imaged sites were biopsied and processed for histopathological grading and measurement of ECTI parameters. An ECTI shape parameter was calculated based on deviation from the linear geometry (ΔLinearity) seen in normal mucosa was measured using MPAM-SHGM and histology. The ECTI was readily visible in MPAM-SHGM and quantitative shape analysis showed ECTI deformation in dysplasia but not in normal mucosa. ΔLinearity was significantly (p < 0.01) higher in dysplasia (0.41±0.24) than normal (0.11±0.04) as measured in MPAM-SHGM and results were confirmed in histology which showed similar trends in ΔLinearity. Increase in ΔLinearity was also statistically significant for different grades of dysplasia. In-vivo ΔLinearity measurement alone from microscopy discriminated dysplasia from normal tissue with 87.9% sensitivity and 97.6% specificity, while calculations from histology provided 96.4% sensitivity and 85.7% specificity. Among other quantifiable architectural changes, a progressive statistically significant increase in epithelial thickness was seen with increasing grade of dysplasia. MPAM-SHGM provides new noninvasive ways for direct characterization of ECTI which may be used in preclinical studies to investigate the role of this interface in early transformation. Further development of the method may also lead to new diagnostic approaches to differentiate non-neoplastic tissue from precancers and neoplasia, possibly with other cellular and layer based indicators of abnormality

Autoantibodies to Ca2+ binding protein Calnuc is a potential marker in colon cancer detection.

Calnuc is a calcium (Ca2+) binding protein found in both Golgi and cytoplasm, and it may play a role in G protein- and Ca2+-regulated signal transduction events. This study was designed to investigate the possibility of whether Calnuc protein might be a tumor-associated antigen (TAA) that induces autoantibody response in human cancers, and to evaluate the feasibility of the Calnuc antigen-antibody system as a marker in cancer detection. Purified full-length recombinant Calnuc protein was used as an antigen in enzyme-linked immunoassay and Western blotting for the detection of autoantibodies in cancers. Sera from 447 patients with 9 different types of cancer were analyzed. Although the frequency of autoantibody to Calnuc was found to be 4.7% in total groups of cancer, it was not significantly different to that of normal individuals (1.2%). However, the frequency of autoantibody to Calnuc in colon cancer (11.5%) was significantly higher than that in normal individuals (1.2%). The expression analysis of Calnuc in multiple colon cancer tissues by immunohistochemistry on tissue array further confirmed the high specificity of Calnuc in colon cancer. Of 69 colon cancer tissue specimens examined, 41 tissues (59.4%) overexpressed Calnuc, while normal colon tissues did not show any expression of Calnuc. The subcellular distribution analysis of Calnuc examined by subcellular fractionation and immunofluorescence indicates that Calnuc is a membrane associated protein and mostly distributed in Golgi, which is consistent with previous reports. With adding Calnuc into a TAA array (including p53, c-myc, cyclin B1, cyclin D1), the cumulative frequency of antibody to multiple TAAs in colon cancer was raised to 65.4% which is significantly higher than the cumulative frequency in normal individuals (6.1%). This indicates that a mini-array of multiple TAAs which includes Calnuc might provide a novel non-invasive approach to enhance antibody detection for colon cancer diagnosis