Cancer Stem Cells in Head and Neck Squamous Cell Cancer

Abstract

Appropriate treatment of head and neck squamous cell cancer (HNSCC) remains one of the most difficult challenges in head and neck oncology. Overall survival of patients with HNSCC remains at approximately 50% at 5 years. Surgical therapy can be mutilating and often has significant effects on swallowing, speech, and physical appearance. The addition of chemotherapy to radiation treatment has shown efficacy in organ preservation in some sites in the head and neck, but has resulted in limited improvement in survival rates. HNSCC resistance to chemotherapy has limited the usefulness of chemotherapy in the treatment of this disease. We have recently demonstrated that human head and neck squamous cell cancers contain a tumorigenic, so-called cancer stem cell, subpopulation of cells that can self-renew and produce differentiated cells that form the bulk of the tumor. These tumorigenic HNSCC cells have a distinct phenotype and can be identified by a surface marker. Current treatment for HNSCC regimens may selectively kill the differentiated cancer cells, producing tumor regression while sparing the cancer stem cells, leading to tumor regrowth and relapse. It is important for us to understand why HNSCC does not respond to chemotherapy and to identify new targeted treatments that can overcome resistance and improve patient outcomes. Further study of HNSCC stem cells will increase our knowledge of this devastating disease and allow us to develop novel treatments.

Cancer Stem Cells in Head and Neck Squamous Cell Carcinoma: A Review

“…The following are key features of cancer stem cell hypothesis (Prince et al, 2008): i) Only a small fraction of the cancer cells within a tumor have tumorigenic potential when transplanted into immunodeficient mice;…”

Association of differential β‐catenin expression with Oct‐4 and Nanog in oral squamous cell carcinoma and their correlation with clinicopathological factors and prognosis

“…The cancer stem cell hypothesis states that a subpopulation of cells in cancerous tissues with tumor inducing capacity as well as stem cell-like characteristics is responsible for carcinogenesis. These cells are termed as cancer stem cells [2]. However, studies on the molecular mechanisms related to cancer stem cells remains obscure.…”

Cancer Stem Cells and Response to Therapy

“…It has been demonstrated that CSCs exist in various tumor types and the signaling pathways involved in CSC self-renewal and differentiation seems to be common in different tumor types (Boman and Huang, 2008;Dirks, 2008;Huff and Matsui, 2008;Kakarala and Wicha, 2008;Prince and Ailles, 2008;Sell and Leffert, 2008;Takaishi et al, 2008). Therefore, there is the possibility that therapies targeting these common pathways be effective against a wide spectrum of tumor types.…”