Role of SIX1, EYA2, and E-cadherin in ovarian carcinoma. Evidence on epithelial-mesenchymal transition from an immunohistochemical study.

This study aims to investigate the expression of SIX1, EYA2, and E-cadherin in ovarian cancer (OC). It was conducted on 97 cases of surface epithelial tumors (SEOTs). Immunohistochemistry (IHC) staining for the three markers was applied to archival paraffin-embedded sections. Results of semi-quantitative scoring were statistically compared, correlated with clinic-pathologic parameters, response to therapy and with patient survival. RESULTS: There was a significant association of SIX1 expression in the intratumoral stroma (ITS) with malignant cases (P < 0.0001). There was a significant direct correlation between tumour cell expression of SIX1 and EYA2 (P = 0.03) and an inverse correlation between SIX1 and E-cadherin (P = 0.03). Additionally, there were direct correlations between SIX1 expression and larger tumour size (P = 0.05), high mitosis (P < 0.0001), and advanced FIGO stage (P = 0.06), and between EYA2 expression and LN metastasis (P = 0.02), and low apoptotic index (P = 0.007). Only SIX1 expression in ITS affected the patient survival by univariate analysis (P = 0.004). CONCLUSIONS: SIX1/EYA2 complex may have a poor prognostic role in OC. SIX1 expression in ITS may be used as a predictive marker of stromal invasion in ovarian borderline tumors and could affect patients' survival in OC. SIX1, EYA2, and E-cadherin may constitute a pathway that could be targeted to stop the progression of SEOTs.

Evaluation of the Role of ALDH1 as Cancer Stem Cell Marker in Colorectal Carcinoma: An Immunohistochemical Study.

INTRODUCTION: Colorectal Carcinoma (CRC) is the third most commonly diagnosed cancer in males. Stem Cells (SC) may be involved in tumour growth, including colon cancer. Aldehyde Dehydrogenase 1 (ALDH1) is a detoxifying enzyme that might modulate SC proliferation. AIMS: To evaluate the immunohistochemical expression of ALDH1 as stem cell marker in the pathogenesis of colorectal carcinoma. MATERIALS AND METHODS: This retrospective study included 71 colorectal specimens (49 colorectal carcinoma, 13 adenoma and 9 normal cases) that were collected from Pathology Department, Faculty of Medicine, Menoufia University during the period from 2011 to 2015. All cases were stained by ALDH 1 antibody. Survival data were available for 31cases. RESULTS: There was a statistical significant association between epithelial positivity of ALDH1 and younger age (p=0.003), right sided tumour (p=0.038), presence of lymph node invasion (p= 0.04), ulcerating gross picture (p=0.01) and presence of vascular invasion (p=0.05). Moreover, there was statistical significant association between stromal positivity of ALDH1 and smaller tumour size (p=0.03) and inverse association between stromal expression of ALDH1 and grade of tumour (p=0.000) and perineural invasion (p= 0.05). Furthermore, there was an inverse significant relation between CD44 and ALDH1 expression (p=0.001). Univariate recurrence free survival analysis revealed the bad prognostic impact of high grade (p=0.03) and female sex (p=0.02) on patient outcome. CONCLUSION: Epithelial expression of ALDH1 might be associated with poor prognosis while its stromal expression might be associated with good prognosis.