BACR19
Expression of human embryonic stem cell genes OCT4, NANOG in breast and thyroid carcinoma compared to testicular carcinoma
Zahra Madjd1, Mohsen Asadi lari2
1Cellular Molecular Research Centre, Iran University of Medical Sciences, Tehran, Iran, 2Oncopathology Research Centre, Iran University of Medical Sciences, Tehran, Iran
Background
Cancer stem cells are a small subpopulation of cells within a tumor, which are responsible for maintaining the tumor mass. A number of factors that govern the fate of adult stem cells also play a role in malignant cell transformation, such as OCT4 and NANOG. OCT4 is largely expressed in human germ cell tumors and its expression reflect an increase in the germ cell (OCT4 +) to somatic cell (OCT4-) ratio in these tumors. NANOG is a key regulator of embryonic stem cell (ESC) self-renewal and pluripotency and there are close similarity between ESC and carcinoma in situ testis (CIS), including high NANOG expression.
Method This study included 200 tumour tissues to determine the expression of OCT4 and NANOG on breast and thyroid tumors compared to testicular carcinoma using immunohistochemistry. The prevalence of these cells then correlated with prognostic factors.Results
It has been observed that seminoma and breast carcinoma express a common stem cell profile including NANOG and OCT4. Therefore stem cell genes may either play a direct role in different types of carcinoma progression or serve as valuable markers of tumorigenesis.
Conclusion
This study explores the possible role of NANOG and OCT4 in the pathogenesis of breast and thyroid tumors compared to testicular tumors, especially those derived from germ cells. Therefore we analyze the expression of NANOG and OCT4 in a panel of tumors including breast, thyroid and testicular neoplasms and establish the ontogeny of expression in the normal human testis.
