J Korean Assoc Oral Maxillofac Surg.  2011 Apr;37(2):97-108. 10.5125/jkaoms.2011.37.2.97.

Cancer stem cell theory and update in oral squamous cell carcinoma

• Kim DH
• Yun JY
• Lee JH
• Myoung H
• Kim SM

• KMID: 2136998
• DOI: http://doi.org/10.5125/jkaoms.2011.37.2.97

Abstract

Cancer stem cells have stem cell-like features, such as the ability for self-renewal and differentiation but show unlimited growth because they have the lost normal regulation of cell growth. Cancer stem cells and normal stem cells have similar features. They show high motility, diversity of progeny, robust proliferative potential, association with blood vessels, immature expression profiles, nestin expression, epidermal growth factor (EGF)-receptor expression, phosphatase and tensin homolog (PTEN) expression, hedgehog pathway activity, telomerase activity, and Wnt pathway activity. On the other hand, with cancer cells, some of these signaling pathways are abnormally modified. In 1875, Cohnheim suggested the concept of cancer stem cells. Recently, evidence for the existence of cancer stem cells was identified. In 1994, the cancer stem cells'specific cell surface marker for leukemia was identified. Since then, other specific cell surface markers for cancer stem cells in solid tumors (e.g. breast and colon cancer) have been identified. In oral cancer, studies on cancer stem cells have been performed mainly with squamous cell carcinomas. Oral cancer specific cell surface markers, which are genes strongly expressed in oral cancer and cancer stem cell specific side populations, have been identified. Cancer stem cells are resistant to radiotherapy and chemotherapy. Therefore, to eliminate malignant tumors efficiently and reduce the recurrence rate, therapy targeting cancer stem cells needs to be performed. Currently, studies targeting the cancer stem cells'specific signaling pathways, telomerase and tumor vasculatures are being done.

Keyword

Neoplastic stem cells; Cell surface antigens; Signal pathways; Mouth neoplasms; Cancer chemotherapy

MeSH Terms

Antigens, Surface
Blood Vessels
Breast
Carcinoma, Squamous Cell
Colon
Epidermal Growth Factor
Hand
Hedgehogs
Intermediate Filament Proteins
Leukemia
Microfilament Proteins
Mouth Neoplasms
Neoplastic Stem Cells
Nerve Tissue Proteins
Recurrence
Signal Transduction
Stem Cells
Telomerase
Wnt Signaling Pathway
Antigens, Surface
Epidermal Growth Factor
Intermediate Filament Proteins
Microfilament Proteins
Nerve Tissue Proteins
Telomerase

Figure

• 

  Fig. 1. Signalling pathways that regulate self-renewal mechanisms during normal stem cell development and during transformation27.

• 

  Fig. 2. Stochastic model and Hierarchial model40.

• 

  Fig. 3. Stem cell specific and conventional cancer therapie110.

Reference

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