Biological and Genetic Characteristics of Tumor-Initiating Cells in Colon Cancer

Abstract

It was confirmed that CD133+ cells in colon cancer are useful markers for the detection of tumor-initiating cells. Intimate biological and genetic features of CD133+ cells in colon cancer cell lines were also revealed. The biological characteristics of CD133+ cells and differentially expressed genes in these cells will help elucidate more details of tumor-initiating cells in colon cancer.

Characterization of the conversion between CD133+and CD133-cells in colon cancer SW620 cell line

“…1A) revealed the following prominent features: (1) The levels of CD133 varied very significantly among those cell lines, and the percentage of the cells expressing CD133 ranged from 0.04% (LoVo) to 98.3% (WiDr); (2) Except the HT29 cell line, all others expressed CD133 at relatively stable levels. The levels of CD133 in HT29 cells were in constant change within a range from 19.1% to 88.7%, which was also reflected in other differential reported results; 11,12 (3) The flow cytometry histogram (CD133 vs. cell counts) was a unimodal curve for the majority of the examined cell lines, indicating that each of those cell lines has a single cell population although the cells may express CD133 at varied levels. The only exception was SW620, the histogram of which was bimodal, manifesting that there existed two cell subpopulations marked by CD133 -or CD133 + expression; at the mRNA level and by western blotting at the protein level (Fig.…”

“…3F) + cells are more proliferative than their negative counterparts, and the CD133 phenotype is dependent on cell cycle progression, or influenced by energy metabolism or correlated with differentiation degree. 6,8,11,18,19 However, our results showed that the very similar growth curves detected either by cell counting or by SRB assays, together with the equal levels of PCNA and β-catenin (Fig. 4C), collectively revealed the comparable proliferative potential of the cells between those two subpopulations.…”

CD133 expression is correlated with lymph node metastasis and vascular endothelial growth factor-C expression in pancreatic cancer

“…CD133 expression has been detected in several normal tissues including neuroepithelium, embryonic and adult immature epithelia (Weigmann et al, 1997;Corbeil et al, 2000;Richardson et al, 2004;Shmelkov et al, 2005). The association between CD133 and CSCs has been documented in haematological malignancies (Horn et al, 1999) and since then, CD133 expression has been identified in various types of solid tumours, including brain tumours (Singh et al, 2003(Singh et al, , 2004Beier et al, 2007), prostate cancer (Collins et al, 2005), kidney cancer (Florek et al, 2005), melanoma (Klein et al, 2007;Monzani et al, 2007), ovarian cancer (Ferrandina et al, 2007), hepatocellular carcinoma (Suetsugu et al, 2006;Ma et al, 2007;Yin et al, 2007), and colon cancer (Ieta et al, 2007;O'Brien et al, 2007;Ricci-Vitiani et al, 2007).…”

“…In colon cancer, a small number of CD133 þ cells can maintain themselves as well as differentiate and re-establish tumour heterogeneity after serial transplantation (O'Brien et al, 2007;Ricci-Vitiani et al, 2007). CD133 þ cells in colon cancer cell lines have a high degree of tumorigenic ability in vivo, and their levels of proliferation, colony formation, and invasive ability were found to be higher than those of CD133 À cells in vitro (Ieta et al, 2007). There are also small populations of CD133 þ cells in human hepatocellular carcinoma (HCC) cell lines and primary HCC tissues (Yin et al, 2007).…”

Prognostic Value of Immunohistochemical Expressions of the Stem Cell Biomarker "LGR5" and the Proliferation Biomarker "TPX2" in Colorectal Carcinoma

“…LGR5 and TPX2 in colorectal carcinoma residual CSCs may lead to metastasis and recurrence of colorectal cancer through multilineage differentiation and self-renewal after surgical resection of the primary cancer [34] . Discovering a novel stem cell biomarker such as LGR5 which its expression was associated with poor prognosis, recurrence and metastases of CRC can help to detect therapeutic modality targeting CSCs through eradicating LGR5 positive CSCs and leading to decrease progression recurrence, metastases and improving the CRC prognosis.…”