Second-harmonic imaging microscopy for identifying colorectal intraepithelial neoplasia.

In this study, second-harmonic imaging microscopy was used to monitor precancerous colorectal lesions at different stages. It was found that the morphology of glands and lamina propria in mucosa changes with the progression of colorectal diseases from normal to low-grade intraepithelial neoplasia to high-grade intraepithelial neoplasia and this microscopy has the ability of direct visualization of these warning symptoms. Furthermore, two morphologic variables were quantified to determine the changes of glands and collagen in lamina propria during the development of colorectal intraepithelial neoplasia. These results suggest that second-harmonic imaging microscopy has the potential in label-freely and effectively distinguishing between normal and precancerous colorectal tissues, and will be helpful for early diagnosis and treatment of colorectal diseases.

Overexpression of cyclin E isoforms correlates with poor prognosis in rectal cancer.

AIMS: To investigate the expression of cyclin E isoforms in rectal cancer and its relations to clinicopathological factors and survival. MATERIALS AND METHODS: Cyclin E expression was assessed by Western blot in 360 resected rectal cancer patients of stage I to III. Multivariate analysis was applied to indicate the independent prognostic markers in this cohort. RESULTS: Nineteen percent, 24% or 29% patients exhibited elevated levels of full-length (FL) cyclin E, low-molecular-weight (LMW) cyclin E or total cyclin E in their tumors respectively. Significant correlation was observed between cyclin E expression with blood vessel invasion, deeply invasive tumors, histology grade and lymph node metastasis. Moreover, patients with high levels of LMW-cyclin E or total cyclin E had a poorer 5-year overall survival than did patients with low levels of LMW-cyclin E or total cyclin E. In multivariate analysis, both the LMW-cyclin E and total cyclin E, but not FL-cyclin E, remained independent prognostic indicators in both patients with stage I to III and in those with early stage. Patients with elevated LMW- or total cyclin E levels had a hazard ratio for death from rectal cancer of 6.302 (95% CI, 1.903-17.81, p = 0.001) or 4.332 (95% CI, 1.298-16.362, p = 0.001). CONCLUSION: Overexpression of the LMW-cyclin E or total cyclin E is a strong predictor for poorer survival in patients with rectal cancer. Therefore, evaluating cyclin E expression may provide useful prognostic information for resectable rectal cancer patients.