Preventive use of gabapentin to decrease pain and systemic symptoms in patients with head and neck cancer undergoing chemoradiation.

BACKGROUND: Radiation for patients with head and neck cancer (HNC) is associated with painful mucositis that impacts the delivery of treatment and contributes to high symptom burden. METHODS: This was a prospective, randomized pilot trial. Eligible patients received primary or adjuvant chemoradiation. Patients were randomized to usual care vs usual care plus gabapentin titrated to drug tolerance during radiation. Patients completed a symptom survey at baseline and weekly during therapy. RESULTS: Seventy-nine patients were enrolled in the study (38 control, 41 treatment). At interim analysis, gabapentin use resulted in a decrease in pain (P = .004), with the biggest decreases being in the latter weeks of therapy. By week 7, the median pain score in the treatment group was below the 0.25 quantile of the control group. CONCLUSION: Prophylactic use of gabapentin during chemoradiation for HNC patients resulted in a decrease in pain, neurosensory symptoms, and general systemic symptoms.

Enhanced radiation damage of tumor vasculature by mTOR inhibitors.

It is known that radiation activates the phosphoinositol-3 kinase (PI3K)/Akt pathway and that inhibition of PI3K or Akt sensitizes tumor vasculature to radiotherapy. Mammalian target of rapamycin (mTOR) is a downstream target of Akt, and we hypothesized that irradiation activates mTOR signaling in both glioma and endothelial cells (ECs) and that radiosensitization results from inhibiting mTOR signaling. mTOR inhibitors, rapamycin and RAD001 (everolimus) were found to radiosensitize vascular ECs, but failed to sensitize glioma cells as determined by clonogenic assay. Therefore, we investigated the anti-angiogenic effects of mTOR inhibitors. Increased phospho-mTOR protein was detected in irradiated human umbilical vein endothelial cells (HUVEC), but not in GL261 glioma cells. Phospho-S6, a biomarker for mTOR signaling, was also found to be induced following irradiation in HUVEC and this effect was inhibited by PI3K or mTOR inhibitors. Significant increase in cleaved caspase 3 was detected when Rad001 was combined with radiation. Endothelial tube formation was significantly diminished following treatment with rapamycin and 3 Gy of radiation. Histological sections of GL261 tumors from mice showed a greatly reduced vascular density when treated with RAD001 and radiation. Power Weighted Doppler of glioma xenografts in mice showed a significant reduction in vasculature and blood flow compared with mice treated with 3 Gy or RAD001 alone. We conclude that irradiation activates mTOR signaling in vascular endothelium and that rapamycin and RAD001 increased apoptosis of ECs in response to radiation. To the authors' best knowledge this is the first study which demonstrates that mTOR inhibitors may be a way to target the vasculature by radiosensitizing the vascular endothelium resulting in better tumor control as seen in experiments demonstrating increased tumor growth delay in mice treated with rapamycin with radiation compared with mice treat with either treatment alone. We conclude that mTOR inhibitors have increased efficacy as antiangiogenics when combined with radiation.

A specific antagonist of the p110delta catalytic component of phosphatidylinositol 3'-kinase, IC486068, enhances radiation-induced tumor vascular destruction.

The phosphatidylinositol 3'-kinase (PI3k)/protein kinase B (PKB/Akt) signal transduction pathway plays a critical role in mediating endothelial cell survival and function during oxidative stress. The role of the PI3k/Akt signaling pathway in promoting cell viability was studied in vascular endothelial cells treated with ionizing radiation. Western blot analysis showed that Akt was rapidly phosphorylated in response to radiation in primary culture endothelial cells (human umbilical vascular endothelial cells) in the absence of serum or growth factors. PI3k consists of p85 and p110 subunits, which play a central upstream role in Akt activation in response to exogenous stimuli. The delta isoform of the p110 subunit is expressed in endothelial cells. We studied the effects of the p110delta specific inhibitor IC486068, which abrogated radiation-induced phosphorylation of Akt. IC486068 enhanced radiation-induced apoptosis in endothelial cells and reduced cell migration and tubule formation of endothelial cells in Matrigel following irradiation. In vivo tumor growth delay was studied in mice with Lewis lung carcinoma and GL261 hind limb tumors. Mice were treated with daily i.p. injections (25 mg/kg) of IC486068 during 6 days of radiation treatment (18 Gy). Combined treatment with IC486068 and radiation significantly reduced tumor volume as compared with either treatment alone. Reduction in vasculature was confirmed using the dorsal skinfold vascular window model. The vascular length density was measured by use of the tumor vascular window model and showed IC486068 significantly enhanced radiation-induced destruction of tumor vasculature as compared with either treatment alone. IC486068 enhances radiation-induced endothelial cytotoxicity, resulting in tumor vascular destruction and tumor control when combined with fractionated radiotherapy in murine tumor models. These findings suggest that p110delta is a therapeutic target to enhance radiation-induced tumor control.

Internal Lymphedema Correlates with Subjective and Objective Measures of Dysphagia in Head and Neck Cancer Patients.

BACKGROUND: Tumor/treatment-related internal lymphedema (IL) and/or external lymphedema (EL) are associated with functional deficits and increased symptom burden in head and neck cancer patients (HNCP). Previously, we noted association between EL/IL and patient-reported dysphagia using the Vanderbilt Head and Neck Symptom Survey (VHNSS) version 1.0. OBJECTIVE: To determine the relationship between IL/EL and subjective and objective measures of swallowing function. METHODS: Eighty-one HNCP completed: (1) VHNSS version 2.0, including 13 swallowing/nutrition-related questions grouped into three clusters: swallow solids (ss), swallow liquids (sl), and nutrition(nt); (2) physical assessment of EL using Foldi scale; (3) endoscopic assessment of IL using Patterson scale (n = 56); and (4) modified barium swallow study rated by dysphagia outcome and severity scale (DOSS) and in conjunction with a swallow evaluation by National Outcomes Measurement System (NOMS). Examinations were performed at varied time points to assess lymphedema spectrum, from baseline (n = 15, 18.1%) to 18 months post-therapy (n = 20, 24.1%). RESULTS: VHNSS swallow/nutrition items scores correlated with NOMS/DOSS ratings (p < 0.001). Highest correlation was with NOMS: ss (-0.73); sl (-0.61); nt (-0.56). VHNSS swallow/nutrition scores correlated with maximum grade of swelling for any single structure on Patterson scale: ss (0.43; p = 0.001); sl (0.38; p = 0.004); nt (0.41; p = 0.002). IL of aryepiglottic/pharyngoepiglottic folds, epiglottis, and pyriform sinus were most strongly correlated with VHNSS and NOMS ratings. NOMS/DOSS ratings correlated with EL (> = -0.34; p < 0.01). No meaningful correlations exist between VHNSS swallow/nutrition items and EL (< ± 0.15, p > 0.20). CONCLUSIONS: IL correlated with subjective and objective measures of swallow dysfunction. Longitudinal analysis of trajectory and impact of IL/EL on dysphagia is ongoing.

Clusterin as a therapeutic target for radiation sensitization in a lung cancer model.

PURPOSE: Clusterin plays important roles in cell survival and death. Inactivation of clusterin enhances the therapeutic efficacy of chemotherapy in lung cancer models. The purpose of this study was to determine whether inhibition of clusterin by an antisense-based investigative drug enhances radiation sensitization in a lung cancer model. METHODS AND MATERIALS: Cells were transfected with an antisense oligonucleotide (ASO) against clusterin (OGX-011). Apoptosis was determined by 7-aminoactinomycin D staining. Cell survival was examined by 3-(4, 5-methylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) and clonogenic assay. Xenograft model was used to demonstrate tumor growth and tumor blood flow. RESULTS: OGX-011 specifically attenuated the expression of secreted clusterin (prosurvival), with no apparent effect on the expression of nuclear clusterin (proapoptotic). Apoptosis was significantly increased when H460 lung cancer cells were treated with OGX-011 plus radiation. Inhibition of clusterin followed by radiation greatly decreased cell survival. H460 xenografts that were treated with OGX-011 plus radiotherapy demonstrated growth delay beyond 17 days. Doppler studies showed that tumor blood flow was compromised when mice bearing H460 xenografts were treated with OGX-011 and radiation. CONCLUSION: A combination of radiotherapy and OGX-011 improved control of tumor growth and vascular regression in the H460 lung cancer model.

Automatic selection of DBS target points using multiple electrophysiological atlases.

In this paper we study and evaluate the influence of the choice of a particular reference volume as the electrophysiological atlas on the accuracy of the automatic predictions of optimal points for deep brain stimulator (DBS) implants. We refer to an electrophysiological atlas as a spatial map of electrophysiological information such as micro electrode recordings (MER), stimulation parameters, final implants positions, etc., which are acquired for each patient and then mapped onto a single reference volume using registration algorithms. An atlas-based prediction of the optimal point for a DBS surgery is made by registering a patient's image volume to that reference volume, that is, by computing a correct coordinate mapping between the two; and then by projecting the optimal point from the atlas to the patient using the transformation from the registration algorithm. Different atlases, as well as different parameterizations of the registration algorithm, lead to different and somewhat independent atlas-based predictions. We show how the use of multiple reference volumes can improve the accuracy of prediction by combining the predictions from the multiple reference volumes weighted by the accuracy of the non-rigid registration between each of the corresponding atlases and the patient volume.