The effect of tetrathiomolybdate on cytokine expression, angiogenesis, and tumor growth in squamous cell carcinoma of the head and neck.

OBJECTIVE: To assess the effect of tetrathiomolybdate on cytokine expression, angiogenesis, and tumor growth rate in human squamous cell carcinoma (SCC). DESIGN: Three human SCC cell lines were used in this study for both in vitro and in vivo investigations. Conditioned media from untreated and tetrathiomolybdate-treated cell lines were compared with regard to cytokine levels, endothelial cell chemotaxis, endothelial cell tubule formation, and migration and the ability to induce angiogenesis in a rat aortic ring array. In vivo UM-SCC-38 was seeded onto tissue-engineered scaffolds and surgically implanted into the flanks of immunodeficient mice. Tumor growth rates and the level of angiogenesis were compared after 2 weeks of therapy. SETTING: A tertiary care facility. RESULTS: In this study, we demonstrate that tetrathiomolybdate significantly decreases the secretion of interleukin 6 and basic fibroblast growth factor by head and neck SCC (HNSCC) cell lines in vitro. Furthermore, we demonstrate that tetrathiomolybdate significantly decreases the secretion of interleukin 6 and basic fibroblast growth factor by HNSCC cell lines in vitro. Furthermore, tetrathiomolybdate treatment of HNSCC cell lines results in significantly decreased endothelial cell chemotaxis, tubule formation, and neovascularization in a rat aortic ring assay. This in vitro evidence of decreased angiogenesis by tetrathiomolybdate is confirmed in vivo by using a severe combined immunodeficiency disorder mouse model in which tetrathiomolybdate therapy is shown to prevent human blood vessel formation. Finally, human HNSCC implanted into immunodeficient mice grow to a much larger size in untreated mice compared with those treated with 0.7 mL/kg per day of oral tetrathiomolybdate. CONCLUSIONS: These findings illustrate the ability of tetrathiomolybdate to down-regulate proinflammatory and proangiogenic cytokines in HNSCC. These observations are potentially exciting from a clinical perspective because a global decrease in these cytokines may decrease tumor aggressiveness and reverse the resistance to chemotherapy and radiation therapy seen in this tumor type.

Prognostic factors in oral cavity and oropharyngeal squamous cell carcinoma.

BACKGROUND: The survival of patients with head and neck squamous cell carcinoma (HNSCC) remains unaffected despite recent therapeutic advances. To reverse this trend, reliable and clinically applicable markers of tumor aggressiveness must be identified. One such marker may be the tumor-associated macrophage content. The authors hypothesized that tumor-associated macrophages contribute to HNSCC aggressiveness, and the objective of the current study was to prove this hypothesis using mRNA expression analysis and a large cohort of clinical specimens. METHODS: Oligonucleotide microarray analysis was performed on a prospective cohort of 20 patients with previously untreated oral cavity or oropharynx squamous cell carcinoma (OC/OP SCCA) and on normal oropharyngeal mucosa from 4 patients. After determining whether macrophage chemoattractants were produced by tumors, conditioned media from three HNSCC cell lines were used to quantify macrophage migration in an in vitro assay. A high-density tissue microarray of 102 patients with previously untreated OC/OP SCCA was stained immunohistochemically for CD68 to identify tissue macrophages, and the results were correlated with clinicopathologic data and survival. RESULTS: Monocyte chemoattractant protein 1 was up-regulated significantly in tumors compared with normal mucosa (P=0.0025; fold change=1.89). All University of Michigan SCC tumor cell line conditioned media caused a significant increase in macrophage migration (P <0.05). Tissue microarray data revealed that macrophage content of the primary tumor was associated strongly with lymph node metastasis (P <0.0001), extracapsular lymph node spread (P=0.0001), and advanced clinical disease stage (P=0.0002). When it was evaluated along with other clinicopathologic data, the macrophage content was found to be an independent predictor of lymph node metastasis (P <0.0001). CONCLUSIONS: Primary tumor macrophage content is a strong predictor of tumor aggressiveness in HNSCC.