CD10 as a novel marker of therapeutic resistance and cancer stem cells in head and neck squamous cell carcinoma.

BACKGROUND: Cancer stem cells (CSCs) are responsible for treatment failure. However, their identification and roles in resistance are not well established in head and neck squamous cell carcinoma (HNSCC). METHODS: Three HNSCC cell lines (FaDu, Detroit562 and BICR6) were treated with cisplatin or radiation. Cell surface antigens were analysed by LyoPlate, a novel cell surface antigen array. The expression levels of antigens highly expressed after treatments were further compared between cisplatin-resistant Detroit562 cells and its parental line. Association of the candidate antigen with CSCs properties, namely sphere formation and in vivo tumourigenicity, was also examined. RESULTS: CD10, CD15s, CD146 and CD282 were upregulated across the treated cell lines, while the increased expression of CD10 was prominent in the cisplatin-resistant cell line. Isolation mediated by FACS revealed that the CD10-positive subpopulation was more refractory to cisplatin, fluorouracil and radiation than the CD10-negative subpopulation. It also showed an increased ability to form spheres in vitro and tumours in vivo. Moreover, the CD10-positive subpopulation expressed the CSC marker OCT3/4 at a higher level than that in the CD10-negative subpopulation. CONCLUSIONS: CD10 is associated with therapeutic resistance and CSC-like properties of HNSCC. CD10 may serve as a target molecule in the treatment of refractory HNSCC.

Prevalence of human papillomavirus in oral gargles and tonsillar washings.

OBJECTIVES: Human papillomavirus (HPV) infection drives carcinogenesis in the oropharynx. No standard sampling or HPV detection methods for evaluating oropharyngeal HPV infection exist. The prevalence of oral HPV infection in Japan is unknown. MATERIALS AND METHODS: We examined 435 healthy Japanese individuals to address whether adding tonsillar washing to oral gargling would improve HPV detection. We compared HPV assessment using GENOSEARCH HPV31 versus nested PCR and direct sequencing. Associations between HPV infection and demographic and behavioral characteristics were examined. RESULTS: Most participants who were HPV-positive based on oral gargles were also HPV-positive based on tonsillar washings: 11 (64.7%) of 17 on nested PCR and 12 (70.6%) of 17 on GENOSEARCH HPV31. Although HPV infection was more prevalent in oral gargles followed by tonsillar washings than in oral gargles alone, the difference was not statistically significant (nested PCR, 4.8% vs. 3.9%, P = 0.46; GENOSEARCH HPV31, 5.3% vs. 3.9%, P = 0.33). The overall agreement between nested PCR and GENOSEARCH HPV31 was 98.6%, with 76.0% positive agreement. The overall prevalence of oral HPV infection in Japan was 5.7% (95% confidence interval, 3.9-8.3%). Men had a significantly higher prevalence of oral HPV infection than women (8.3% vs. 2.6%, P = 0.02). Infection increased with number of lifetime sexual partners (P < 0.001 for trend). CONCLUSION: The oropharynx is probably the major source of HPV-infected cells in oral gargles. Oral gargling could be a standard sampling method for evaluating oropharyngeal HPV infection. GENOSEARCH HPV31 could be an option for oral HPV detection.

Metabolic tumor volume of metastatic lymph nodes and survival after total laryngectomy in laryngeal and hypopharyngeal cancer.

OBJECTIVES: The prognostic value of metabolic tumor volume (MTV) in locally advanced laryngeal or hypopharyngeal cancer is established in the setting of chemoradiotherapy, while it remains unknown in the setting of upfront total laryngectomy. MATERIALS AND METHODS: We retrospectively analyzed 88 patients receiving total laryngectomy and neck dissection, using Cox regression models. RESULTS AND CONCLUSION: Variables related to metastatic lymph node were associated with overall survival, whereas those related to primary tumor were not. In multivariable models, MTV of metastatic lymph nodes (N-MTV) as a continuous variable (Akaike's information criterion (AIC), 277.5) was equivalent to pathological nodal status (AIC, 278.2; P = 0.40), and superior to pathological nodal classification as an ordinal variable (AIC, 281.4; P < 0.05) in ability of predicting death. The risk of death was increased by 1.2-fold (95% confidence interval (CI), 1.0-1.4; P = 0.03) every 10-ml increment of N-MTV, while patients with pN+ disease were at a higher risk of death by 2.9-fold (95% CI, 1.0-12.2; P < 0.05) compared with patients with pN0 disease. Using recursive partitioning analysis (RPA), we classified the patients as having a low, intermediate, or high risk of death on the basis of N-MTV and extranodal extension (ENE). This RPA classification system exhibited greater concordance with overall survival than the classification considering pathological nodal status and ENE (AIC, 275.8 versus 281.4; P = 0.02). In the setting of upfront total laryngectomy, N-MTV is a critical predictor of mortality. A staging system in which N-MTV is incorporated may better inform adjuvant treatment decisions.

The NOTCH Pathway in Head and Neck Squamous Cell Carcinoma.

Comprehensive genomic analyses have been performed for head and neck squamous cell carcinoma (HNSCC), revealing a significant rate of NOTCH1 mutations and identifying NOTCH1 as the second most frequently mutated gene after TP53. Most NOTCH1 mutations are considered inactivating, indicating that NOTCH1 is a tumor suppressor gene. On the other hand, cohorts from Asian populations with HNSCC have shown activating NOTCH1 mutations. HNSCC with NOTCH1 mutations have a worse prognosis than the NOTCH1 wild-type tumors. Additional data on other NOTCH family members have shown that NOTCH promotes HNSCC progression. NOTCH family members, including NOTCH pathway genes, are upregulated in HNSCC compared with normal tissues, and inhibition of the NOTCH pathway decreases cell proliferation and invasion. NOTCH activity in HNSCC is therefore contextual, and NOTCH in HNSCC is considered to have a bimodal role as a tumor suppressor and an oncogene. In this review, recent understandings of NOTCH pathway genes, including NOTCH genes, in HNSCC are described. In addition, the implications of NOTCH pathway alteration for HNSCC-specific NOTCH-targeted cancer therapy are explored.