Relation of a hypoxia metagene derived from head and neck cancer to prognosis of multiple cancers.

Affymetrix U133plus2 GeneChips were used to profile 59 head and neck squamous cell cancers. A hypoxia metagene was obtained by analysis of genes whose in vivo expression clustered with the expression of 10 well-known hypoxia-regulated genes (e.g., CA9, GLUT1, and VEGF). To minimize random aggregation, strongly correlated up-regulated genes appearing in >50% of clusters defined a signature comprising 99 genes, of which 27% were previously known to be hypoxia associated. The median RNA expression of the 99 genes in the signature was an independent prognostic factor for recurrence-free survival in a publicly available head and neck cancer data set, outdoing the original intrinsic classifier. In a published breast cancer series, the hypoxia signature was a significant prognostic factor for overall survival independent of clinicopathologic risk factors and a trained profile. The work highlights the validity and potential of using data from analysis of in vitro stress pathways for deriving a biological metagene/gene signature in vivo.

Relation of erythropoietin and erythropoietin receptor expression to hypoxia and anemia in head and neck squamous cell carcinoma.

PURPOSE: The use of erythropoietin in head and neck squamous cell carcinoma (HNSCC) has been associated with poor survival. This study examines the protein and mRNA expression of erythropoietin and erythropoietin receptor in HNSCC and their relation to hypoxia, hemoglobin (Hb), and clinical outcome. EXPERIMENTAL DESIGN: The immunohistochemical expression of erythropoietin and erythropoietin receptor was assessed in 151 cases of HNSCC. Expression was compared with the hypoxia-dependent proteins hypoxia-inducible factor-1alpha (HIF-1alpha) and carbonic anhydrase-9 (CA-9) and correlated with clinical outcome. The mRNA expression of erythropoietin and erythropoietin receptor was measured in paired samples of HNSCC. RESULTS: Erythropoietin and erythropoietin receptor were expressed in 95% and 99% of tumors, respectively. Using a weighed expression score, there was a positive correlation between erythropoietin and erythropoietin receptor expression (r = 0.18, P = 0.03). HIF-1alpha (r = 0.38, P < 0.01) and CA-9 (r = 0.26, P = 0.002) correlated with erythropoietin expression, but there was no correlation with erythropoietin receptor. No correlation was found between Hb and erythropoietin (r = 0.07, P = 0.36) or erythropoietin receptor (r = -0.02, P = 0.8), and no survival difference between high and low erythropoietin or erythropoietin receptor expression (P = 0.59 and P = 0.98, respectively). The mRNA expression of erythropoietin (P = 0.03) but not erythropoietin receptor (P = 0.62) was significantly increased in 11 paired samples of HNSCC. CONCLUSION: In vivo, the HIF pathway regulates erythropoietin at the mRNA level but not erythropoietin receptor expression in HNSCC. Anemia does not seem to influence the hypoxic microenvironment of tumors sufficiently to alter the expression of erythropoietin. The effects of exogenous erythropoietin may be acting via receptors expressed on tumor cells in vivo, or on vascular cells, which also express the pathway.

Pharyngeal pouch surgery: a combined open and endoscopic approach.

Pharyngeal pouches are common, particularly in the elderly population, in whom they can cause significant morbidity. The advanced age of many patients and existing comorbidities mean that in some cases neither open nor endoscopic pouch stapling is possible. We present a technique of combined open and endoscopic pharyngeal pouch surgery, which may be used when other therapeutic options are limited.

The relation between hypoxia-inducible factor (HIF)-1alpha and HIF-2alpha expression with anemia and outcome in surgically treated head and neck cancer.

BACKGROUND: Hypoxia promotes tumorigenesis through the hypoxia-inducible factor (HIF) pathway. There are 2 main homologues of the regulatory proteins, HIF-1alpha and HIF-2alpha, which have different effects in genetic knock-out experiments. Anemia may contribute to hypoxia by reducing oxygen delivery, but it is not known whether this influences HIF-alpha expression in tumors. METHODS: The expression of HIF-1alpha, HIF-2alpha, carbonic anhydrase-9 (CA-9), and peripheral hemoglobin (Hb) levels in 151 patients who underwent surgery for head and neck squamous cell carcinoma (HNSCC) were analyzed and related to outcome. RESULTS: High HIF-1alpha was expressed in 45 of 140 tumors (30%), HIF-2alpha was expressed in 21 of 139 tumors (14%), and CA-9 was expressed in 56 of 149 tumors (62%). There was a positive correlation between HIF-1alpha expression and HIF-2alpha expression (P =.0001). HIF-1alpha alone was associated with a worse disease-specific survival (DSS) (P =.05) and disease-free survival (DFS) (P = .03) in multivariate analyses. Nine percent of tumors expressed both high HIF-1alpha and high HIF-2alpha. High HIF-1alpha/high HIF-2alpha expression was an independent prognostic factors in DSS (P = .04) and DFS (P =.005) in multivariate analyses. There was no correlation noted between Hb and HIF-1alpha, HIF-2alpha, or CA-9. CONCLUSIONS: HIF-1alpha alone was correlated with DSS and DFS. The additive effect of HIF-2alpha on poor prognosis suggested that different pathways may be regulated by HIF-2alph. Anemia that was not related to HIF-alpha expression suggests that tumor intrinsic factors regulate HIF-alpha therefore, anemia may be a surrogate marker for other factors that affect outcome.