Two meta-analysis reports have suggested that CD133 expression is significantly associated with shorter survival, and CD133 may play an important role in the progression of colorectal cancer.
By Cox progression analysis, it was shown that CEA/CK/CD133 mRNA in tumor drainage blood was an independent prognostic factor for DFS and OS in patients with Dukes' stage B and C. These results suggest that detecting CEA/CK/CD133 mRNA in tumor drainage blood by the real-time RT-PCR method would have a prognostic value in CRC patients with Dukes' stage B and C.
Expression levels of CD133, a cancer stem cell marker, and of the α-subunit of the dystroglycan (α-DG) complex, have been previously reported to be altered in colorectal cancers.
In the current research, CD133 expression in primary CRC was detected by immunohistochemistry, and an asymmetric BiAb consisting of monomer of chimeric AC133 (mouse anti-human CD133 monoclonal antibody) and single chain of humanized OKT3 was developed to eradicate CD133-expressing tumor cells by arming activated T cells in vitro and in vivo.
In light of the recent discovery of tumor-initiating cancer stem cells (CSCs) in various tumor types, we developed an in vitro CSC model from xenograft tumors established in mice from a colorectal cancer patient tumor in which the CD133+/EpCAM+ population represented tumor-initiating cells.
In order to identify other CRC stem cell-specific genes, we performed a comparative expression profiling of CD133(+) and CD133(-) cell populations in primary and metastatic tumors from four patients with CRC.
To accomplish this aim, we use immunohistochemistry (IHC) and double IHC with different potential stem-like markers, anti-musashi (Msi), anti-CD133, anti- LGR5 and anti-ALDH1 to examine the presentation of stem-like cells in different compartments including adenoma/CRC epithelium, transitional crypts and tumor stroma in colorectal adenoma and CRC.
CD133 expression is a putative cancer stem cell marker and a proposed prognostic marker in CRC, whereas the predictive value of CD133 expression for effect of adjuvant chemotherapy in CRC is unclear.
Initially the size of the CD133-expressing (CD133+) population in eight well-described CRC cell lines was measured by flow cytometry and was found to range from 0% to >95%.
After Cox regression, age, Duck's stage, lymph node metastasis, and CD133 and CD44 proteins co-expression were shown to be the independent prognostic factors of colorectal cancers.
The great majority of the cells expressing CD133 also expressed gastrin precursors in both DLD-1 cells, which retain a stem cell-like subpopulation, and human CRC specimens.
Together, these data show that ABCG2 expression correlates with the presence of CD133-positive cancer cells, and thus is a possible therapeutic target for colorectal cancer.
Collagen was highly deposited in the CRC invasive tumor front (ITF), and the expression of CD133 was higher in ITF compared with normal tissue and the tumor cells.