Thermoradiotherapy in human head and neck squamous cell carcinoma cell lines

Thermoradiosensitivity of 8 cell lines of head and neck squamous cell carcinoma (HO-1-u-1, HSC2, HSC3, HSC4, SAS, KB, Hep2, and Ca9-22) was investigated. The differences of radiosensitivity between the cell line with the highest radiosensitivity and the cell line with the lowest radiosensitivity were 1.7-, 7.7-, and 41-fold at 2, 6 and 8 Gy, respectively. The differences between the cell line with the highest thermosensitivity and the cell line with the lowest thermosensitivity were 2.4-, 6.2- and 34.4-fold at 43 degrees C for 40, 60 and 100 min, and 2.6-, 4.9- and 127-fold at 44 degrees C for 20, 30 and 50 min, respectively. These findings indicated that there were large differences in both radiosensitivity and thermosensitivity among the 8 cell lines. There was a negative relationship between radiosensitivity and thermosensitivity (43 degrees C: r=-0.600, 44 degrees C: r=-0.848) in 7 of 8 cell lines, the exception being the HSC4 cell line, which was resistant to both therapies. Four of the 8 cell lines at 43 degrees C and 5 at 44 degrees C in the radiotherapy combined with thermotherapy showed actual survival rates smaller than the theoretical survival rates. Thus, thermoradiotherapy was deemed effective in the head and neck carcinoma cell lines, although 1 of 8 cell lines was resistant to both radiotherapy and thermotherapy.     

HPV相关的头颈部鳞状细胞癌的研究进展

随着吸烟、饮酒危险因素的相应控制,头颈部鳞状细胞癌的发病率有所下降,但是一部分由高危型HPV16/18感染引起的头颈部鳞癌的发病率却呈明显的上升趋势。HPV相关的头颈部鳞癌因特殊的致病因素而表现出独特的基因表达谱和生物学特性,且对放化疗敏感、预后良好以及有更高的生存率,因此治疗方式也有区别于其他头颈部鳞癌。本文就近些年来关于HPV相关的头颈部鳞癌流行病学特点、致癌机制以及诊断与防治作一综述。     

Changing trends in human papillomavirus-associated head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) continues to be a significant disease with varying rates of incidence and mortality worldwide. Numerous studies have demonstrated that human papillomavirus (HPV) is etiologically linked with a subset of HNSCC, independent of tobacco and alcohol use. This subset of tumor shows increased sensitivity to radiation therapy and association with better outcomes. The study aims to determine the HPV burden and trend among patients with HNSCC in the southern region of the United States over the past 10 years. Of 142 cases from 2000 to 2004, 18 (13%) were positive for high-risk HPV. Nine of these were oropharyngeal tumors, including 4 cases from the tonsil. These constitute 38% (9/24) of all oropharyngeal tumors and 57% (4/7) of tonsillar tumors. Of 35 cases from 2009 to 2010, 14 (40%) were positive for high-risk HPV. Thirteen of these were oropharyngeal tumors, including 9 cases from the tonsil. These constitute 59% (13/23) of oropharyngeal tumors and 64% (9/14) of tonsillar tumors. When data from the 2 periods are combined, the results show that African American patients are less likely to have HPV-associated disease compared with white patients (9% vs 22%). Human papillomavirus-positive and oropharyngeal HNSCC are more likely to be nonkeratinizing (P < .0001). In conclusion, the HPV detection rate in oropharyngeal squamous cell carcinoma increased from 38% to 59% between the 2000-to-2004 and 2009-to-2010 periods.     

Expression of IL-18 in patients with head and neck squamous cell carcinoma

Interleukin-18 (IL-18), a recently described cytokine secreted mainly by macrophages, stimulates interferon-gamma (IFN-gamma) production by natural killer cells and T cells. The purpose of this study was to determine tissue expression and serum levels of IL-18 in head and neck squamous cell carcinoma (HNSCC) and to evaluate ethanol and endotoxin-driven cytokine secretion. In 24 patients with primary HNSCC and 28 healthy controls, PBMC were isolated and incubated with 50 mM ethanol, LPS (doses 25 ng/ml, 250 ng/ml, 2500 ng/ml) and both agents for 24 h. Levels of IL-18 in serum, and cell supernatants were analysed by capture ELISA, IL-18 tissue level by immunoblotting. Serum levels of IL-8, IL-10 and IL-12, IFN-gamma, and endotoxin plasma levels were also determined. Statistical analysis involved Welch t-test and Page's test for trend. The majority of patients with HNSCC had high concentrations of serum IL-18. The level of IL-18 in the sera of these patients had a mean level of 271.7 pg/ml, while the mean IL-18 serum level in healthy controls was 174,0 pg/ml (p<0.001). Levels of IL-10 and IL-12, IFN-gamma were not increased in patients. Endotoxin was not detectable in either group. LPS stimulated dose-dependently IL-18 secretion from PBMC of patients and controls in vitro (p<0.05). Incubation with ethanol alone did not affect basal IL-18 secretion, but ethanol reduced LPS-stimulated IL-18 secretion compared to LPS stimulation alone. The mRNA expression of IL-18 in unstimulated PBMC and the response of PBMC to ethanol and LPS was similar in patients and controls. Our data on elevated serum levels of IL-18 in the majority of HNSCC cancer patients, irrespective of its biological activity, suggest that serum IL-18 might be a candidate for a new marker for HNSCC. The pathways for IL-18 production and its mechanisms of action in patients with HNSCC remain to be determined. Understanding of the immunological pathways might offer new therapeutic options in head and neck cancer in the future.     

Expression profiling and prediction of distant metastases in head and neck squamous cell carcinoma

BACKGROUND: For breast and prostate cancer, a gene expression signature of the tumour is associated with the development of distant metastases. Regarding head and neck squamous cell carcinoma (HNSCC), the only known risk factor is the presence of > or =3 tumour-positive lymph nodes. AIM: To evaluate whether a HNSCC gene expression signature can discriminate between the patients with and without distant metastases. METHODS: Patients with HNSCC with and without distant metastases had >3 tumour-positive lymph nodes, and did not differ with respect to other risk factors. Statistical analysis was carried out using Student's t test, as well as statistical analysis of microarrays (SAM), to assess the false discovery rate for each gene. These analyses were supplemented with a newly developed method that computed deviations from gaussian-order statistics (DEGOS). To validate the platform, normal mucosa of the head and neck was included as control. RESULTS: 2963 genes were differently expressed between HNSCC and normal mucosa (t test; p<0.01). More rigorous statistical analysis with SAM confirmed the differential expression of most genes. The comparison of genes in HNSCC with and without metastases showed 150 differently expressed genes (t test; p<0.01), none of which, however, could be confirmed using SAM or DEGOS. CONCLUSIONS: No evidence for a metastasis signature is found, and gene expression profiling of HNSCC has seemingly no value in determining the risk of developing distant metastases. The absence of such a signature can be understood when it is realised that, for HNSCC in contrast with breast cancer, the lymph nodes are a necessary in-between station for haematogenous spread.     

The opioid growth factor receptor in human head and neck squamous cell carcinoma

Regucalcin is a Ca2+-binding protein, which plays a regulatory role in liver cell functions related to Ca2+. In this study we have cloned cDNA for regucalcin from rabbit, bovine, chicken and toad livers by using rapid amplification of cDNA ends (RACE) method. The nucleotide and amino acid sequences of them are compared with published human, rat and mouse sequences. Comparison analysis revealed that the nucleotide sequences of regucalcin from seven vertebrate species were highly conserved in their coding region. The overall regucalcin proteins in these species consisted of 299 amino acids, and they had 69.9-91.3% identity. Furthermore, phylogenetic analysis showed that regucalcin in seven species appears to form a single cluster. This study demonstrates a great conservation of the regucalcin genes throughout evolution.     

Adenosine metabolism of human mesenchymal stromal cells isolated from patients with head and neck squamous cell carcinoma

BackgroundMesenchymal stromal cells (MSC) are a major component of the tumor microenvironment in patients with head and neck squamous cell carcinoma (HNSCC). MSC display innate and regulatory immunologic functions, very similar to many hematopoietic ‘classical’ immune cells. Conversion of ATP to immunosuppressive adenosine is an immunosuppressive mechanism utilized by other hematopoietic immune cells. The present study explores the adenosine metabolism of tumor derived MSC in comparison to autologous MSC from non-malignant tissue.MethodsFrom HNSCC patients (n = 10), paired MSC were generated from tumor tissue (tMSC) and autologous healthy control tissue (cMSC). Differentiation properties and phenotype (CD105, CD73, CD39, CD90, CD26, CD29) were compared by flow cytometry. Production of immunosuppressive adenosine (ADO) by functionally active ectonucleotidases, CD39 and CD73, was determined by luminescence and mass spectrometry. Suppressive activity of ADO was tested in CFSE proliferation assays of isolated T-cells. Plasticity of cMSC was explored after incubation with tumor-cell conditioned media.ResultsDifferentiation into osteogenic, chondrogenic and adipogenic directions was comparable in tMSC and cMSC. Expression of ectonucleotidases, CD39 and CD73, was decreased in tMSC as compared to corresponding cMSC, which correlated with decreased ATP metabolism in mass spectrometry. Proliferation of CD4⁺ T-cells was significantly suppressed by exogenous ADO. Tumor-conditioned medium was unable to down-regulate ADO production in cMSC.ConclusionWe identified MSC of the oropharyngeal mucosa as an important producer of exogenous ADO. In patients with HNSCC, reduced expression of ADO may contribute to excessive inflammation and tumor growth.     

Allelic loss and tumor pathology in head and neck squamous cell carcinoma.

Allelic loss is a common occurrence in head and neck tumors and has been shown to be an independent predictor of prognosis; however, the relationship between allelic loss and tumor pathology is not well-known. We studied 139 patients who were newly diagnosed with squamous cell cancer of the head and neck to determine whether tumor pathology was correlated with allelic loss at one or more of eight different regions on chromosomes 3p, 5q, 8p, 9p, 10p, 18q, and 21q. At each chromosomal region, loss of heterozygosity at any one of three or four highly polymorphic microsatellite markers that spanned the region in question was considered evidence for allelic loss. A pathologist scored all tumors for seven tumor pathology and host interface parameters. Mean allelic loss across all eight regions was associated with mitotic index (P =.034) and inflammatory response (P =.005). For allelic loss at specific chromosomal regions, the most statistically significant trends were between overall tumor grade and 3p14.2-p13 (P =.014), mitotic index and 3p24.3-p14.3 (P =.026), 9p24.2-p21 (P =.004) and 18q12.3-q23 (P =.009), inflammatory response and 3p14.2-p13 (P =.008) and 9p24.2-p21 (P =.001), desmoplastic response and 9p24.2-p21 (P =.009), and pattern of invasion and 21q21-q22.2 (P =.015). Our results suggest that genes involved in tumor suppression and oncogenesis can potentially be classified based on specific pathologic events in head and neck squamous cell carcinogenesis that they modify.     

Consistent chromosomal losses in head and neck squamous cell carcinoma cell lines

Clonal chromosomal abnormalities were characterized in nine cell lines established from squamous cell carcinomas of the head and neck. Aneuploidy was a common feature; one cell line was near-diploid, three were near-triploid, four were near-tetraploid, and one cell line showed extensive variation in chromosome numbers. Consistent numerical abnormalities included loss of the sex chromosomes in six cell lines, losses of chromosomes 2 and 21 in six and five cell lines, respectively, and gain of chromosome 20 in five cell lines. Recurrent structural rearrangements included del(10)(q22-q26) (seven cell lines), i(5)(p10) (six cell lines), i(8)(q10) (six cell lines), add(19)(q13) (six cell lines), del(4)(q21-q31.3) (five cell lines), i(3)(q10) (four cell lines), del(12)(p11.1-p12) (four cell lines), and add (18)(q21-q23) (four cell lines). Other changes were noted in lower frequencies. Loss of specific regions on chromosomes 2, 3p, 4q, 5q, 8p, 10q, 12p, 18q, 19q, and 21 suggests that they may represent sites of putative tumor suppressor genes, loss of which may play a role in the pathogenesis of squamous cell carcinomas of the head and neck. Alternatively, gain of chromosomal region 3q, 5p, and 8q due to isochromosome formation suggests that more than one mechanism is involved in malignant transformation. Cytogenetic evidence of gene amplification was found in two cell lines; as an hsr(11)(q 13) in one and as dmins in the other. The clonal karyotypes of four cell lines were compared with those of their respective primary tumors. In all cell lines, clonal evolution had occurred, with loss of some rearrangements present in the primary tumors or the gain of additional abnormalities.     

High-risk cutaneous squamous cell carcinoma of the head and neck

Nonmelanoma skin cancers (squamous cell and basal cell carcinomas) occur at an epidemic rate in many countries with the worldwide incidence increasing. The sun-exposed head and neck are the most frequent sites for these cancers to arise and in most patients diagnosed with a cutaneous squamous cell carcinoma, local treatment is usually curative. However, a subset is diagnosed with a high-risk cutaneous squamous cell carcinoma. High-risk factors include size (>2 cm), thickness/depth of invasion (>4 mm), recurrent lesions, the presence of perineural invasion, location near the parotid gland, and immunosuppression. These patients have a higher risk (>10-20%) of developing metastases to regional lymph nodes (often parotid nodes), and in some cases also of experiencing local morbidity (perineural invasion), based on unfavourable primary lesion and patient factors. Despite treatment, many patients developing metastatic cutaneous squamous cell carcinoma experience mortality and morbidity usually as a consequence of uncontrolled metastatic nodal disease. It is therefore important that clinicians treating nonmelanoma skin cancers have an understanding and awareness of these high-risk patients. The aim of this article is to discuss the factors that define a high-risk patient and to present some of the issues pertinent to their management.     

Epidermal growth factor receptor: a novel biomarker for aggressive head and neck cutaneous squamous cell carcinoma

There is currently no prognostic tool that reliably predicts the risk of metastasis in cutaneous squamous cell carcinoma, most of which occur in the head and neck region. Epidermal growth factor receptor has received much interest in recent years with the advent of epidermal growth factor receptor-targeted molecular therapy in clinical oncology. We investigate the role of epidermal growth factor receptor as a biomarker for head and neck cutaneous squamous cell carcinoma. Using immunohistochemistry and fluorescence in situ hybridization, we assessed the epidermal growth factor receptor protein expression and gene copy in 3 groups of head and neck cutaneous squamous cell carcinoma: primary lesions not associated with metastasis (P), primary lesions associated with subsequent metastasis (PM), and metastatic nodal disease (M). Epidermal growth factor receptor overexpression was detected in 36% and 79% of P and PM cases, respectively. Epidermal growth factor receptor overexpression was significantly associated with PM (P = .03) and was found to be an independent prognostic factor for metastasis on multivariate analysis (P = .05). However, epidermal growth factor receptor overexpression was only maintained in 47% of cases in the M group. None of the 27 cases that overexpressed the epidermal growth factor receptor protein showed gene amplification: the results were uninterpretable in 2, and polysomy and balanced disomy were detected in 5 and 20 cases, respectively. These observations may have important prognostic and therapeutic implications for head and neck cutaneous squamous cell carcinoma.     

Chromosomal alterations during metastasis formation of head and neck squamous cell carcinoma.

Comparative genomic hybridization (CGH) was used to detect chromosomal changes during metastasis formation of head and neck squamous cell carcinomas (HNSCCs). In total, 92 tumors of 54 patients were investigated. In 34 of these, the metastases were compared to the corresponding primary tumors. The group of metastatic tumors was also compared with 20 nonmetastatic tumors. Gain of 3q was the earliest genetic marker for invasion and metastasis and also correlated with poor prognosis. Additional metastasis-associated lesions were gains on 11q13, 7q11.2, 1q21-q22, and losses on 8p, 11p14, 11q14-qter, 10p12, 10q, and 14q. The incidence of the chromosomal changes was used to evaluate their significance and temporal order of appearance during tumor dissemination, thus leading to an extended progression model of HNSCC. In the clonality analysis, three different methods revealed a mean concordance of 64 and 68% between pairs of primaries and metastases, respectively. Using different similarity scores, the correct metastasis was identified from the pool of all metastatic lesions in 19-26 of the 34 cases. The study supplements previous genetic results on HNSCC pathogenesis and provides criteria for multiple tumor analysis.     

Ran promotes the proliferation and migration ability of head and neck squamous cell carcinoma cells

HNSCC is an aggressive tumor that often recurrence and metastasis. Although the treatment of HNSCC has improved over the past few decades, it is easy to recurrence even after comprehensive treatment. Ran is a small Ras-related GTPase belonging to the Ras superfamily. Recently, Ran has been proven to be an important oncogene involved in the metastatic progression of many human cancers. But there is seldom research on HNSCC about Ran. This study revealed the relationship between Ran expression and HNSCC characteristics, investigated the expression and role of Ran in HNSCC tissues and cells by means of immunohistochemistry, qRT-PCR, CCK-8, FCM and transwell migration assays. The results indicated that HNSCC tissues had significantly higher Ran expression than adjacent non-tumor tissues. The overall survival rate was significantly lower in patients with Ran-positive tumors than in those with Ran-negative tumors. Moreover, Ran was positively correlated with tumor grade, lymph node metastasis and recurrence. Ran was also high expressed in the HNSCC cell lines (PCI-37B and SCC9) and down regulated of Ran could evidently inhibit their proliferation, migration and down-regulate of Met protein. In conclusion, our findings suggested Ran could promote the proliferation and migration ability of HNSCC cells. Ran may play an important role in the development of HNSCC and may serve as a novel prognostic indicator of HNSCC.     

Molecular biology of squamous cell carcinoma of the head and neck

Squamous cell carcinoma of the head and neck (HNSCC) is a heterogeneous but largely preventable disease with complex molecular abnormalities. It arises from a premalignant progenitor followed by outgrowth of clonal populations associated with cumulative genetic alterations and phenotypic progression to invasive malignancy. These genetic alterations result in inactivation of multiple tumour suppressor genes and activation of proto-oncogenes, including p16(ink4A), p53, cyclin D1, p14(ARF), FHIT, RASSF1A, epidermal growth factor receptor (EGFR), and Rb. Intramucosal migration and clonal expansion of transformed cells with formation of abnormal genetic fields appear to be responsible for local recurrences and development of second primary tumours.     

Two simple translocations in a primary squamous cell carcinoma of the head and neck

A 59-year-old white man was diagnosed with primary squamous cell carcinoma at the base of the tongue (clinical stage T4N3aM0). Cytogenetic analysis of the metaphase spreads obtained from primary cultures of the tumor tissue revealed a clonal abnormality with a 46,XY,t(2;6) (p23;q21),t(18;19)(q21;q13) karyotype.     

Expression of protein tyrosine kinases in head and neck squamous cell carcinomas

Protein tyrosine kinases (TKs) are overexpressed in many carcinomas and sarcomas. We studied the expression of the following TKs in head and neck squamous cell carcinoma (HNSCC): platelet-derived growth factor receptor (PDGFR), c-kit, epidermal growth factor receptor (EGFR), and a serine-threonine kinase, Akt. Formalin-fixed, paraffin-embedded tumor blocks from 44 consecutive patients with primary HNSCC and 5 specimens of benign pharyngeal and laryngeal mucosa were retrieved for immunohistochemical analysis. Of the specimens, 38 had enough material to stain for all 4 antibodies. The study included 21 pharyngeal (base of tongue, 14; tonsil, 6; soft palate, 1), 16 laryngeal, and 1 floor of the mouth carcinoma. All 4 kinases in the tumor samples were expressed highly (PDGFR, 95%-100%; EGFR, 38%-43%; c-kit, 50%-86%; p-Akt, 57%-81%), with EGFR, c-kit, and p-Akt significantly higher than in benign samples. None of the kinase expressions correlated with disease-free survival. The expression of the kinases raises the possibility of treatment of HNSCC by tyrosine and serine-threonine kinase inhibitors.