Aldehyde dehydrogenase 1: a specific cancer stem cell marker for human colorectal carcinoma.

Since the identification of cancer stem cells (CSCs) a new understanding of tumor occurrence and development has evolved. According to the stem cell (SC) theory, colorectal carcinoma (CRC) SCs may be derived from mutations in normal intestinal cells. CSCs can be defined by their cell of origin (SCs or early progenitor cells). Thus, through a shared stem cell marker between CSCs and SCs, it is possible to investigate the association between its expression and the various clinicopathological features in patients with CRC. Aldehyde dehydrogenase 1 (ALDH1) is an appropriate marker. The present study was performed to examine the role of ALDH1 in CRC. Through indirect fluorescence antibody staining, the association between ALDH1 protein expression and various clinicopathological parameters was investigated. Furthermore, enzyme­linked immunosorbent assay (ELISA) was used to investigate the differing content of ALDH1 between CRC tissues and normal colorectal tissues. The results revealed that ALDH1 expression was markedly associated with tumor stage, Dukes' stage and the level of tumor cell differentiation. Using ELISA, it was demonstrated that there was a greater level of ALDH1 in CRC tissue than in normal colorectal tissue. Therefore, ALDH1 levels can be used as a useful parameter for pathological evaluation of tissue histology and to predict disease prognosis.

Expression and prognostic value of tumor stem cell markers ALDH1 and CD133 in colorectal carcinoma.

The identification of cancer stem cells (CSCs) has improved the understanding of tumor occurrence and development. According to CSC theory, colorectal carcinoma (CRC) may be derived from these few cells. Thus, markers for CSCs may lead to the identification of CSCs and investigation of the correlation with various clinicopathological features and survival time in human CRC patients. Aldehyde dehydrogenase 1 (ALDH1) and CD133 (also known as Prominin-1 or AC133) were involved in the current study. The aim of the present study was to identify CSCs through markers of CSCs and to explore the value of the CSC markers, ALDH1 and CD133, in human CRC. The correlation between ALDH1 and CD133 protein expression and the various clinicopathological parameters were investigated through immunohistochemistry (IHC). In addition, the Kaplan-Meier method was used to estimate patients' overall survival. Correlation of the survival differences between ALDH1- or CD133-positive expression and negative controls was analyzed by the log-rank test. Furthermore, the correlation between the expression of ALDH1 and CD133 was assessed by Spearman's rank correlation. A marked correlation between the differentiation degree and expression of ALDH1 in tumor cells was demonstrated, but not with CD133 expression. In addition, it was demonstrated that low-stage tumors exhibit a higher expression of ALDH1 or CD133 staining compared with high-stage tumors. Meanwhile, CD133 expression was associated with lymph node metastasis-positive cases, but ALDH1 expression was not. Furthermore, compared with negative cases, ALDH1-positive patients exhibited a poor prognosis. However, no significant difference was identified between CD133-positive and -negative cases in terms of survival time. Overall, the results of the present study indicated that ALDH1 and CD133 may serve as useful markers of CSC to predict disease prognosis and clinicopathological characteristics of human CRC.

Therapeutic effect of co-transplantation of neuregulin-1-transfected Schwann cells and bone marrow stromal cells on spinal cord hemisection syndrome.

The aim of this present study is to evaluate the therapeutic effect of co-transplantation of neuregulin-1-transfected Schwann cells (SCs) and bone marrow stromal cells (BMSCs) on a rat model of spinal cord hemi-section injuries (Brown-Séquard syndrome), which is relevant to human clinical spinal cord injury. Both in vivo and in vitro data we received demonstrated that co-transplantation BMSCs with NRG1-transfected SCs reduced the size of cystic cavities, promoted axonal regeneration and hind limb functional recovery in comparison with SCs or BMSCs transplantation alone or together, and this treatment could provide important insights into potential therapies of spinal cord hemi-section injuries.