Twenty-eight percent of metastatic lymph nodes from occult primary tumors were HPV positive. There was no survival difference associated with HPV status. Most of the HPV-positive patients in this study were tobacco users who had similar survival to HPV-negative patients, so caution should be used in interpreting HPV status in these patients.

Curcumin appears to be a safe, bioactive food compound that is a potential chemopreventive for patients at a high risk for head and neck squamous cell carcinoma (HNSCC). Identification and validation of intermediate endpoints is an important step in evaluating chemopreventive agents. AKT/ MTOR pathway biomarkers are intrinsic to the carcinogenic process as well as the mechanism of intervention with curcumin. Antiproliferative effects of curcumin were assayed in 9 HNSCC and a keratinocyte cell line. Nicotine, a genotoxic alkaloid involved in tobacco addiction, forms DNA adducts and has been implicated in upper aerodigestive tract cancer promotion. The antiproliferative effects of curcumin were associated with inhibition of the AKT/MTOR pathway in presence and absence of nicotine, which also induced this pathway. Curcumin was highly effective at suppressing growth of SCC40 xenografts and its activity is associated with modulation of MTOR's downstream target pS6. Curcumin at 15 mg significantly increased survival (286 AE 37 vs. 350 days) in the 4NQO carcinogenic model survival study. A major cause of lethal progression of HNSCC is local regional migration and invasion of malignant cells, and curcumin significantly inhibited cancer cell migration and invasion in vitro and in vivo where downregulation of pS6 was associated with a significant decrease in MMP-9. This is the first study to demonstrate that curcumin inhibits the adverse effects of nicotine by blocking nicotine-induced activation of the AKT/MTOR pathway in HNSCC, which retards cell migration. These studies indicate that inhibiting the AKT/MTOR pathway with curcumin may be useful as an oral chemopreventive agent. Cancer Prev Res; 3(12); 1586-95. Ó2010 AACR.

Objectives-No reliable molecular biomarker is currently available for clinical application in the management of head and neck cancer patients. The AKT/MTOR pathway is activated in 90-100% of HNSCC and could be promising biomarkers closely linked to cancer incidence.Methods-Oral mucosa from non-cancer patients were compared to HNSCC tumors and junctional zone mucosa. The candidate biomarkers MTOR, AKT, 4EBP1, and S6 kinase, signaling components upstream and downstream of MTOR that appear dysregulated in HNSCC were evaluated using immunohistochemistry (IHC) and western blot.Results-Expression of phosphorylated AKT and phosphorylated MTOR were significantly higher in cancer patient tumors compared to non-cancer oral mucosa samples (p=0.004 and p=0.026 respectively) by western. pMTOR and p4EBP1 expression were higher in patient junctional zones compared to tumors (p=0.017 and p=0.022 respectively) and no difference in p-AKT or p-S6 expression in HNSCC patients' junctional zone compared to tumors. IHC demonstrated p-MTOR expression was 81.9% sensitive and 100% specific in differentiating cancer from non-cancer mucosa, while p-4EBP1 expression by IHC was only 50.0% sensitive and 95.5% specific in differentiating normal mucosa from HNSCC (p<0.01).Conclusions-Phosphorylated MTOR appears to be a reliable biomarker by both western (p=0.026) and IHC in human head and neck cancer (p<0.001). Moreover, phosphorylated AKT, which is immediately upstream of MTOR, is a potential biomarker that should be further studied. Clinical trials with MTOR inhibitors are being evaluated for HNSCC, and selecting patients that are likely to respond to these inhibitors requires identifying and validating predictive biomarkers of response.

A new method of nanoparticle formulation for low water-soluble materials was demonstrated on the example of curcumin. The drug was dissolved in organic solvent that is miscible with water (ethanol) and drug nucleation was initiated by gradual worsening the solution with addition of aqueous polyelectrolyte assisted by ultrasonication. Curcumin crystals of 60-100 nm size were obtained depending on the component concentrations, sonication power, and an initial solvent. A layer-bylayer shell assembly with biocompatible polyelectrolytes was used to provide particle coating with high surface potential and stabilization of drug nanocolloids. Polyelectrolyte layer-by-layer encapsulation allowed sustained drug release from nanoparticles over the range of 10-20 hours.Many anticancer drugs are poorly soluble in water (curcumin, paclitaxel, tamoxifen, etc). Currently there is no established nanoscale delivery system for the continuous slow release of such drugs other than micelles, although micelles contain a very small percentage of the desired drugs 1-3 . Other approaches for drug nanoformulation include ultrasonicated decomposition of drug powder 4 and drug loading to polymeric (often gelatin or polysaccharide) coacervates [5][6][7][8] . For such formulations, a usual size of drug carriers is 200-300 nm, which is not small enough for the most efficient medical applications.Natural polyphenolic compounds are interesting as substances with variety of biological activity. High antioxidant, antiviral, and anticancer activities have been proven for plant extracts and polymeric tannins including their isolated individual compounds (such as curcumin) [9][10][11][12] . In this paper we describe a new approach for the preparation of drug nanocolloids with diameters less than 100 nm which is based on sonication assisted nucleation of drug particles from their solutions in organic solvents. An aggregation of the formed nanoparticles was avoided by polycation adsorption onto particles followed by the polyelectrolyte layer-by-layer (LbL) nanoshell formation [13][14][15][16][17][18] . The following procedure was used for formation stable curcumin nanocolloids through controlled crystallization initiated by worsening saturated curcumin alcohol solutions (Scheme 1). Curcumin powder was dissolved in 60 % ethanol / water solution (curcumin was obtained from Sabinsa and all other chemicals were purchased from Sigma-Aldrich). After curcumin been completely dissolved, we added aqueous polycations, poly(allylamine hydrochloride), PAH, or biodegradable protomine sulfate, (PS) and started ultrasonication with UIP1000, Hielscher instrument, at 100 Wt per mL of solution. During the sonication, water was slowly added into the solution. Because of the adding water, solvent becomes more polar, causing decrease of curcumin solubility, and Correspondence to: Yuri Lvov, ylvov@latech.edu. NIH Public Access Author ManuscriptLangmuir. Author manuscript; available in PMC 2011 June 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author M...