Normal vs cancer thyroid stem cells: the road to transformation

Abstract

Recent investigations in thyroid carcinogenesis have led to the isolation and characterisation of a subpopulation of stem-like cells, responsible for tumour initiation, progression and metastasis. Nevertheless, the cellular origin of thyroid cancer stem cells (SCs) remains unknown and it is still necessary to define the process and the target population that sustain malignant transformation of tissue-resident SCs or the reprogramming of a more differentiated cell. Here, we will critically discuss new insights into thyroid SCs as a potential source of cancer formation in light of the available information on the oncogenic role of genetic modifications that occur during thyroid cancer development. Understanding the fine mechanisms that regulate tumour transformation may provide new ground for clinical intervention in terms of prevention, diagnosis and therapy.Oncogene advance online publication, 11 May 2015; doi:10.1038/onc.2015.138

Estrogen and thyroid cancer is a stem affair: A preliminary study

“…Based on the fetal and CSC carcinogenesis models for the thyroid gland [29], the interaction between SCs and progenitors with hormonal pathways could be potential mechanisms to explain estrogen involvement. Xu and colleagues were among the first to report the estrogenic effect on SCs in thyroid disease isolated from goiter tissue [26].…”

Pathological processes and therapeutic advances in radioiodide refractory thyroid cancer

“…This hypothesis has been especially postulated as a potential origin of ATC. However, this could also explain the occurrence of poorly differentiated TC originating from thyroid precursor cells, including thyroblasts or prothyrocytes (Hoshi et al 2007, Lan et al 2007, Fagman & Nilsson 2011, Zane et al 2016. This is supported by the striking resemblance between thyroid-specific gene expression profiles of well-differentiated TC, poorly differentiated TC and ATC on the one hand and end-stage differentiated thyroid follicles, thyroid precursor and thyroid progenitor cells on the other.…”

Thyroid Stem Cells: Concept and Clinical Implications

“…Thyroid CSC was first isolated by Mitsutake et al who postulated that the presence of a small subset of cells in the mature thyroid is responsible for cancer initiation and maintenance (42). At this point, it is not clear whether the origin of this subset of cells is normal cells that have undergone transformation, or existing stem cells that have become activated (47).…”

“…This important process is essential in embryonic development and has also been implicated in initiation and progression of tumour metastasis (52,53). Thus, during this reversible process carcinoma cells acquire mesenchymal gene expression patterns and properties (47).…”