From embryonic stem cells to testicular germ cell cancer - should we be concerned?

• Published in: International journal of andrology Vol. 29; no. 1; pp. 211 - 218
• Main Authors: Almstrup, Kristian, Sonne, Si Brask, Hoei-Hansen, Christina E., Ottesen, Anne Marie, Nielsen, John E., Skakkebæk, Niels E., Leffers, Henrik, Meyts, Ewa Rajpert-De
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-02-2006
• Subjects: cancer stem cells; carcinoma in situ; Carcinoma in Situ - genetics; Carcinoma in Situ - metabolism; Carcinoma in Situ - pathology; embryonic stem cells; Germinoma - genetics; Germinoma - metabolism; Germinoma - pathology; Humans; Male; Neoplasms, Germ Cell and Embryonal - genetics; Neoplasms, Germ Cell and Embryonal - metabolism; Neoplasms, Germ Cell and Embryonal - pathology; Seminoma - genetics; Seminoma - metabolism; Seminoma - pathology; Stem Cells - pathology; testicular germ cell cancers; Testicular Neoplasms - genetics; Testicular Neoplasms - metabolism; Testicular Neoplasms - pathology
• ISSN: 0105-6263; 1365-2605
• DOI: 10.1111/j.1365-2605.2005.00643.x

Summary
Since the discovery of testicular carcinoma in situ (CIS) – the precursor cell for the vast majority of germ cell tumours – it has been proposed that CIS cells could be derived from transformed primordial germ cells or gonocytes. Here, we review recent discoveries not only substantiating that initial hypothesis but also indicating that CIS cells have a striking phenotypic similarity to embryonic stem cells (ESC). Many cancers have been proposed to originate from tissue‐specific stem cells [so‐called ‘cancer stem cells’ (CSC)] and we argue that CIS may be a very good example of a CSC, but with exceptional features due to the retention of embryonic pluripotency. In addition, considering the fact that pre‐invasive CIS cells are transformed from early fetal cells, possibly due to environmentally induced alterations of the niche, we discuss potential risks linked to the uncontrolled therapeutic use of ESC.