Detection of cancer stem cell-related markers in different stages of colorectal carcinoma patients of Indian origin by immunohistochemistry.

CONTEXT

Although the incidence rate of colorectal cancer (CRC) in all Indian cancer registries is very close to the lowest rate in the world, westernization has shown an increasing trend in the recent years. Recurrence is reported in CRC because the slowly proliferating stem cells escape the chemotherapeutic regimen.

AIM

To detect the presence of CD133 and CD44 in human CRC specimens and to correlate the level of marker expression with tumor staging.

MATERIALS AND METHODS

We included 26 colorectal carcinoma patients between 20 and 70 years of age. Histological and immunohistochemical analysis of CD133 and CD44 was done in sections of 5 μm prepared from paraffin-embedded blocks with most representative areas.

STATISTICAL ANALYSIS

All analyses were performed using Microsoft Excel 2010 and SPSS version 22.

RESULTS

CD133 expression was seen exclusively on the cell membrane at the glandular luminal surface with dot-like cytoplasmic staining. In the normal mucosa, CD44 expression was seen in the superficial region of the cell, whereas in most of the carcinomas, the staining was localized in the basolateral region of the cell. Both CD133 and CD44 showed significant correlation with tumor stage.

CONCLUSIONS

In the present study, CD133 and CD44 show significant correlation with tumor staging. Cancer stem cell markers have shown similar pattern of expression in the patients of Indian origin. Using combination of markers for staging is preferred as it increases the sensitivity and specificity.