Identity matters: cancer stem cells and tumour plasticity in head and neck squamous cell carcinoma

Abstract

Head and neck squamous cell carcinoma (HNSCC) represents frequent yet aggressive tumours that encompass complex ecosystems of stromal and neoplastic components including a dynamic population of cancer stem cells (CSCs). Recently, research in the field of CSCs has gained increased momentum owing in part to their role in tumourigenicity, metastasis, therapy resistance and relapse. We provide herein a comprehensive assessment of the latest progress in comprehending CSC plasticity, including newly discovered influencing factors and their possible application in HNSCC. We further discuss the dynamic interplay of CSCs within tumour microenvironment considering our evolving appreciation of the contribution of oral microbiota and the pressing need for relevant models depicting their features. In sum, CSCs and tumour plasticity represent an exciting and expanding battleground with great implications for cancer therapy that are only beginning to be appreciated in head and neck oncology.

Extracellular vesicles from Aggregatibacter actinomycetemcomitans exhibit potential antitumorigenic effects in oral cancer: a comparative in vitro study

“…Although interesting, this is not surprising given the genetic and phenotypic differences between primary and metastatic cancer cells, including their stemness and plasticity (Salem and Salo 2023 ). For instance, the metastatic cancer cells exhibit high potential to acquire transitional phenotypic states, mediate drug resistance, and initiate endothelial-like capillaries (Hujanen et al 2021 ; Salem and Salo 2023 ). However, studies on the bacterial EVs and cancer are limited, which reflects the newness of this interesting field.…”

The road after cancer: biomaterials and tissue engineering approaches to mediate the tumor microenvironment post-cancer treatment

“…One particular aspect of the TME worthy of note is the presence of cancer stem cells (CSCs) and their plasticity-a property that enables cells to change their phenotypic expression as a result of environmental cues, without causing any genetic mutation. CSCs have been found to exhibit enhanced self-renewal, differentiation and tumorigenesis in multiple cancer types (Kruyt, 2023;Salem and Salo, 2023). For these reasons, complete obliteration of CSCs is a major factor that should be considered when looking for effective therapy methods.…”

Feline SCCs of the Head and Neck Display Partial Epithelial-Mesenchymal Transition and Harbor Stem Cell-like Cancer Cells

“…Following a cellular program termed epithelial-mesenchymal transition (EMT), epithelial tumor cells can reversibly switch to a mesenchymal phenotype via E-cadherin suppression allowing EMT transcription factors to promote enhanced expression of mesenchymal proteins. The latter drives extracellular matrix (ECM) degradation, cell motility, invasion, and metastasis [5][6][7][8][9]. In addition, tumor cells can adopt an endothelial phenotype that can build up an alternative system of microvessels ("vasculogenic mimicry") facilitating metastases [10].…”

“…In addition, tumor cells can adopt an endothelial phenotype that can build up an alternative system of microvessels ("vasculogenic mimicry") facilitating metastases [10]. Moreover, tumor cells can acquire a stem cell-like phenotype that has the ability to self-renew, transdifferentiate, and migrate [5,[11][12][13][14]. Long-lived cancer stem cells (CSCs) show a pronounced resistance to stress factors such as DNA damage, reactive oxygen species, or hypoxia, and because of this, they are multidrug resistant.…”