No abstract

Two classes of insulin-like growth factor I (IGF-I) cDNAs were isolated from an adult rat liver library using a human IGF-I cDNA probe. The two types of rat IGF-I cDNA differed by the presence or absence of a 52-base pair insert which altered the derived C-terminal amino acid sequence of the E peptide, but not the 3'-untranslated region or the sequence coding for the mature IGF-I protein. When probes derived from these cDNA clones were hybridized to Northern blots of rat mRNA, specific bands of 8.6, 2.1, and 1.0-1.4 kilobases were seen. Hybridization to poly(A)+ RNA from various tissues from GH-treated and control rats demonstrated an increase in IGF-I mRNA due to GH treatment in all tissues examined.

Background. The aim of this study was to examine biomolecular profiles in a cohort of young adults with squamous cell cancers (SCCs) of the oral tongue.Methods. We identified all patients aged 18 to 39 years diagnosed with SCC of the oral tongue at our institution. Immunohistochemical (IHC) staining was performed for p16 INK4a , epidermal growth factor receptor (EGFR), phosphorylated-EGFR (pEGFR), p53, and ERCC1. Human papillomavirus (HPV) testing was performed using in situ hybridization (ISH) and polymerase chain reaction (PCR). Biomarker expression and HPV status were correlated with outcomes.Results. We identified 25 patients with sufficient tumor samples. Median age at diagnosis was 30 years (range, 20-39 years). p16INK4a overexpression was observed in 11 of 25 patients, whereas HPV-16 positivity was observed in none of the tumor samples by ISH and 2 of the tumor samples by PCR. p16INK4a positivity was correlated with improved relapse-free survival (hazard ratio [HR] ¼ 0.23, p ¼ .01) and overall survival (HR ¼ 0.28, p ¼ .05). Neither EGFR, pEGFR, p53, nor excision repair cross-complementing rodent repair deficiency, complementation group 1 (ERCC1) expression correlated with outcome on univariate analysis.Conclusions. p16 INK4a overexpression was common and was a marker of favorable prognosis. p16INK4a overexpression was not a reliable predictor of HPV positivity in our cohort.