22 research outputs found
Cellular Uptake and Internalization of Hyaluronan-based Doxorubicin and Cisplatin Conjugates
Background
Hyaluronan (HA) is a ligand for the CD44 receptor which is crucial to cancer cell proliferation and metastasis. High levels of CD44 expression in many cancers have encouraged the development of HA-based carriers for anti-cancer therapeutics.
Purpose
The objective of this study was to determine whether HA conjugation of anticancer drugs impacts CD44-specific HA-drug uptake and disposition by human head and neck cancer cells.
Methods
The internalization and cellular disposition of hyaluronan-doxorubicin (HA-DOX), hyaluronan-cisplatin (HA-Pt), and hyaluronan-cyanine7 (HA-Cy7) conjugates were investigated by inhibiting endocytosis pathways, and by inhibiting the CD44–mediated internalization pathways that are known to mediate hyaluronan uptake in vitro.
Results
Cellular internalization of HA was regulated by CD44 receptors. In mouse xenografts, HA conjugation significantly enhanced tumor cell uptake compared to unconjugated drug.
Discussion
The results suggested that the main mechanism of HA-based conjugate uptake may be active transport via CD44 in conjunction with a clathrin–dependent endocytic pathway. Other HA receptors, hyaluronan–mediated motility receptor (RHAMM) and lymphatic vessel endothelial hyaluronan receptor (LYVE-1), did not play a significant role in conjugate uptake.
Conclusions
HA conjugation significantly increased CD44 mediated drug uptake and extended the residence time of drugs in tumor cells
Mandibular myofibrosarcoma of childhood: surgical resection & reconstruction with fibula flap Miofibrossarcoma mandibular na infância: ressecção cirúrgica e reconstrução com retalho fibular
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MANAGEMENT OF THE NECK IN MERKEL CELL CARCINOMA OF THE HEAD AND NECK : UNIVERSITY OF MIAMI EXPERIENCE
Sarcopenia and Treatment Toxicity in Older Adults Undergoing Chemoradiation for Head and Neck Cancer: Identifying Factors to Predict Frailty
This study was performed to identify treatment related toxicities in older adults undergoing concurrent chemoradiotherapy for head and neck cancer and nutritional and skeletal muscle measures that might identify frailty. Imaging analysis was done with the following skeletal muscle measurements: skeletal muscle index (SMI), skeletal muscle density (SMD), and skeletal muscle gauge (SMG). Patients were dichotomized by age into younger (<70 years old, 221 patients) and older age groups (≥70 years old, 51 patients). Low SMI was more common in older patients (86.7%) compared to younger patients (51.7%, p < 0.01), as were low SMD (57.8% vs. 37.3%, p = 0.012) and low SMG (76.1% vs. 44.2%, p < 0.01), despite having similar BMIs (27.3 kg/m2 versus 27.7 kg/m2, p = 0.71). Older patients were significantly more likely to experience chemotherapy toxicity than younger patients (54.9% versus 32.3%, p < 0.01). On multivariate analysis age (p < 0.01), current smoking status (p < 0.01), and low SMI (p < 0.01) remained as significant predictors for missed chemotherapy cycles or discontinuation. Older patients were more likely to require ≥5-day radiation breaks than younger patients (27.5% versus 8.6%, p < 0.01). On multivariate analysis, age (p < 0.01), low albumin status (p = 0.03), and low SMI (p = 0.04) were identified as predictors of prolonged radiation treatment breaks. Based on the results of our study, sarcopenia may be used as an additional marker for frailty alongside traditional performance status scales
Quantitative clinical outcomes of therapy for head and neck lymphedema
Purpose: Head and neck surgery and radiation cause tissue fibrosis that leads to functional limitations and lymphedema. The objective of this study was to determine whether lymphedema therapy after surgery and radiation for head and neck cancer decreases neck circumference, increases cervical range of motion, and improves pain scores. Methods and materials: A retrospective review of all patients with squamous cell carcinoma of the oral cavity, oropharynx, or larynx who were treated with high-dose radiation therapy at a single center between 2011 and 2012 was performed. Patients received definitive or postoperative radiation for squamous cell carcinoma of the oral cavity, oropharynx, or larynx. Patients were referred to a single, certified, lymphedema therapist with specialty training in head and neck cancer after completion of radiation treatment and healing of acute toxicity (typically 1-3 months). Patients underwent at least 3 months of manual lymphatic decongestion and skilled fibrotic techniques. Circumferential neck measurements and cervical range of motion were measured clinically at 1, 3, 6, 9, and 12 months after completion of radiation therapy. Pain scores were also recorded. Results: Thirty-four consecutive patients were eligible and underwent a median of 6 months of lymphedema therapy (Range, 3-12 months). Clinically measured total neck circumference decreased in all patients with 1 month of treatment. Cervical rotation increased by 30.2% on the left and 27.9% on the right at 1 month and continued to improve up to 44.6% and 55.3%, respectively, at 12 months. Patients undergoing therapy had improved pain scores from 4.3 at baseline to 2.0 after 1 month. Conclusions: Lymphedema therapy is associated with objective improvements in range of motion, neck circumference, and pain scores in the majority of patients
Cellular uptake and internalization of hyaluronan-based doxorubicin and cisplatin conjugates
Development and Characterization of an In Vitro Model for Radiation-Induced Fibrosis.
Radiation-induced fibrosis (RIF) is a major side effect of radiotherapy in cancer patients with no effective therapeutic options. RIF involves excess deposition and aberrant remodeling of the extracellular matrix (ECM) leading to stiffness in tissues and organ failure. Development of preclinical models of RIF is crucial to elucidate the molecular mechanisms regulating fibrosis and to develop therapeutic approaches. In addition to radiation, the main molecular perpetrators of fibrotic reactions are cytokines, including transforming growth factor-β (TGF-β). We hypothesized that human oral fibroblasts would develop an in vitro fibrotic reaction in response to radiation and TGF-β. We demonstrate here that fibroblasts exposed to radiation followed by TGF-β exhibit a fibrotic phenotype with increased collagen deposition, cell proliferation, migration and invasion. In this in vitro model of RIF (RI