hes1-protein--human and Mouth-Neoplasms

Notch pathway molecules crosstalk with Wnt/β-catenin signaling cascade in stem cells and tumors. However, the correlation between the expression pattern of Notch intracellular domain NICD, Hes-1 and c-Myc has not been studied in oral squamous cell carcinoma. The aim of this study is to investigate the correlation and prognostic significance of NICD, Hes-1 and c-Myc in oral cancer. Immunohistochemistry was used to study the expression pattern of NICD, Hes-1 and c-Myc in oral preneoplastic and neoplastic tissues. In addition, double immunofluorescence was used to examine the co-localization of NICD, Hes-1 and c-Myc in H314 cells. The expression pattern of NICD and Hes-1 was gradually increased from normal to dysplasia to carcinoma. Interestingly, statistically significant correlation was not observed between NICD, Hes-1 and c-Myc in oral squamous cell carcinoma. Furthermore, NICD+/c-Myc+ and Hes-1+/c-Myc+ double positive cases showed worst survival when compared with other cases in oral cancer. Notch signaling molecules, NICD and Hes-1, are found to be involved in the progression of oral squamous cell carcinoma. Interestingly, NICD, Hes-1 and c-Myc may have independent roles in oral cancer. On the other hand, we have demonstrated that NICD+/c-Myc+ and Hes-1+/c-Myc+ double positivity might be used as independent prognostic indicator of oral carcinoma.

Topics: Aged; Basic Helix-Loop-Helix Transcription Factors; Epithelium; Female; Homeodomain Proteins; Humans; Male; Middle Aged; Mouth Neoplasms; Nestin; Precancerous Conditions; Protein Structure, Tertiary; Proto-Oncogene Proteins c-myc; Receptors, Notch; Reference Values; Survival Analysis; Transcription Factor HES-1

Cancer stem-like cell (CSC; also known as tumor initiating cell) is defined as a small subpopulation of cancer cells within a tumor and isolated from various primary tumors and cancer cell lines. CSCs are highly tumorigenic and resistant to anticancer treatments. In this study, we found that prolonged exposure to tumor necrosis factor alpha (TNFα), a major proinflammatory cytokine, enhances CSC phenotype of oral squamous cell carcinoma (OSCC) cells, such as an increase in tumor sphere-forming ability, stem cell-associated genes expression, chemo-radioresistance, and tumorigenicity. Moreover, activation of Notch1 signaling was detected in the TNFα-exposed cells, and suppression of Notch1 signaling inhibited CSC phenotype. Furthermore, we demonstrated that inhibition of a Notch downstream target, Hes1, led to suppression of CSC phenotype in the TNFα-exposed cells. We also found that Hes1 expression is commonly upregulated in OSCC lesions compared to precancerous dysplastic lesions, suggesting the possible involvement of Hes1 in OSCC progression and CSC in vivo. In conclusion, inflammatory cytokine exposure may enhance CSC phenotype of OSCC, in part by activating the Notch-Hes1 pathway.

Topics: Basic Helix-Loop-Helix Transcription Factors; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Transformation, Neoplastic; Homeodomain Proteins; Humans; Mouth Neoplasms; Neoplastic Stem Cells; Receptor, Notch1; Transcription Factor HES-1; Tumor Necrosis Factor-alpha

The constitutive activation of the Notch pathway has been demonstrated in various types of malignancies. However, it remains unclear how the Notch pathway is involved in the pathogenesis of oral squamous cell carcinoma (OSCC). We investigated the expression of Notch pathway molecules in OSCC cell lines and biopsy specimens and examined the effect of Notch pathway inhibition. Reverse transcription-polymerase chain reaction revealed upregulation of Notch1, Notch2, Jagged1, HES1 and HEY1 in both OSCC cell lines and biopsy specimens. Immunohistochemical examination showed that the Notch intracellular domain accumulates in the nucleus of cells in OSCC cell lines and biopsy specimens. In addition, Jagged1 is expressed in the cytoplasm of cells in OSCC cell lines and biopsy specimens. Furthermore, Notch pathway inhibition using a gamma-secretase inhibitor prevented the growth of OSCC in vitro. These findings suggest that inhibition of the Notch pathway suppresses OSCC growth and may be a useful approach for the treatment of patients with OSCC.

Topics: Aged; Amyloid Precursor Protein Secretases; Basic Helix-Loop-Helix Transcription Factors; Biopsy; Carcinoma, Squamous Cell; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Female; Homeodomain Proteins; Humans; Immunohistochemistry; Mouth Neoplasms; Protease Inhibitors; Receptor, Notch1; Receptor, Notch2; Receptors, Notch; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Time Factors; Transcription Factor HES-1; Up-Regulation