Tumor epidermal growth factor receptor (EGFR) and EGFR PY1068 are independent prognostic indicators for head and neck squamous cell carcinoma
Menée à partir d'échantillons tumoraux prélevés sur 193 patients atteints d'un carcinome épidermoïde de la tête et du cou, cette étude montre une association entre le niveau d'expression tumorale des récepteurs EGFR et EGFR PY1068 et la survie des patients
Purpose:To assess the prognostic value of EGFR molecular characteristics of head and neck squamous cell carcinoma (HNSCC). Patients and Methods: HNSCC tumors from patients prospectively enrolled in either an Early Detection Research Network (EDRN) study and treated with surgery without an EGFR-targeted agent (N=154) or enrolled in a chemoradiation trial involving the EGFR-targeted antibody cetuximab (N=39) were evaluated for EGFR gene amplification by fluorescence in situ hybridization (FISH) and EGFR protein by immunohistochemical (IHC) staining. Fresh-frozen tumors (EDRN) were also evaluated for EGFR protein and site-specific phosphorylation at Y992 and Y1068 using reverse-phase protein array (RPPA) (n=67). Tumor (n=50) EGFR and EGFRvIII mRNA levels were quantified using real-time PCR. Results:EGFR expression by IHC was significantly higher in the EDRN tumors with EGFR gene amplification (P<0.001), and a similar trend was noted in the cetuximab-treated cohort. In the EDRN and cetuximab-treated cohorts elevated EGFR by IHC was associated with reduced survival (p=0.019 and p=0.06, respectively). Elevated expression of total EGFR and EGFR PY1068 were independently significantly associated with reduced progression-free survival in the EDRN cohort (HR=2.75; 95% CI=1.26-6.00 and HR=3.29; 95% CI=1.34-8.14, respectively). Conclusions: In two independent HNSCC cohorts treated with or without cetuximab, tumor EGFR levels were indicative of survival. Tumor EGFR PY1068 levels provided prognostic information independent of total EGFR.
Clinical Cancer Research , résumé, 2012