Mark Whipple

Angiogenic heterogeneity in head and neck squamous cell carcinoma: biological and therapeutic implications

The literature contains numerous references describing heterogeneity for tumor phenotypes including cell proliferation, invasiveness, metastatic potential, and response to therapies. However, data regarding angiogenic heterogeneity are limited. In this study, we investigated the degree of intertumoral angiogenic heterogeneity present in head and neck squamous cell carcinomas (HNSCC). In addition, we investigated the biological relevance that this heterogeneity may have in the context of cytokine directed antiangiogenic therapy. Keratinocytes were harvested from HNSCC specimens using laser capture microdissection (LCM). Gene expression profiling of the RNA extracted from these specimens demonstrated variability in the expression of angiogenesis-related genes. Hierarchical clustering and principal component analyses (PCA) demonstrated the presence of unique patient clusters, suggesting that there may be two potentially distinct pathways by which HNSCC induce angiogenesis. Immunohistochemistry for VEGF, IL-8/CXCL8, HGF, and FGF-2, cytokines that play functional roles in HNSCC angiogenesis was performed on the original patient samples as well as a larger panel of normal, dysplastic and HNSCC specimens to validate the heterogeneous expression observed in the gene expression profiling studies. Finally, the therapeutic response of HNSCC tumor xenografts to anti-VEGF therapy was found to be dependent on the amount of VEGF produced by the tumor cells. These findings support the hypothesis of intertumoral angiogenic heterogeneity. They imply that there are differences with regard to the specific molecular mechanisms by which individual tumors within the same histological type induce angiogenesis. Moreover, they demonstrate the need for a more in-depth understanding of the variability of the angiogenic phenotype within a given type of neoplasm when designing cytokine targeted antiangiogenic therapies. Finally, they suggest that studies in conjunction with the ongoing clinical trials that explore the correlation between target expression and clinical outcome are warranted.

Tumor-specific genetic expression profile of metastatic oral squamous cell carcinoma †

Metastasis is the most important predictor of survival in patients with oral squamous cell carcinoma (OSCC). We tested the hypothesis that there is a genetic expression profile associated with OSCC metastasis.

A Genomic Predictor of Oral Squamous Cell Carcinoma

Objectives/Hypothesis: The objective was to identify a genomic profile that predicts the likelihood of oral squamous cell carcinoma compared with normal oral mucosa in unknown tissue samples.

Endothelial and circulating C19MC microRNAs are biomarkers of infantile hemangioma

Infantile hemangioma (IH) is the most common vascular tumor of infancy, and it uniquely regresses in response to oral propranolol. MicroRNAs (miRNAs) have emerged as key regulators of vascular development and are dysregulated in many disease processes, but the role of miRNAs in IH growth has not been investigated. We report expression of C19MC, a primate-specific megacluster of miRNAs expressed in placenta with rare expression in postnatal tissues, in glucose transporter 1-expressing (GLUT-1-expressing) IH endothelial cells and in the plasma of children with IH. Tissue or circulating C19MC miRNAs were not detectable in patients having 9 other types of vascular anomalies or unaffected children, identifying C19MC miRNAs as the first circulating biomarkers of IH. Levels of circulating C19MC miRNAs correlated with IH tumor size and propranolol treatment response, and IH tissue from children treated with propranolol or from children with partially involuted tumors contained lower levels of C19MC miRNAs than untreated, proliferative tumors, implicating C19MC miRNAs as potential drivers of IH pathogenesis. Detection of C19MC miRNAs in the circulation of infants with IH may provide a specific and noninvasive means of IH diagnosis and identification of candidates for propranolol therapy as well as a means to monitor treatment response.

The lytic activation of KSHV during keratinocyte differentiation is dependent upon a suprabasal position, the loss of integrin engagement, and calcium, but not the interaction of cadherins

We previously found that KSHV (HHV-8) lytic activation occurs during differentiation of oral keratinocytes in organotypic raft cultures. To further investigate the spatial and temporal aspects of KSHV lytic activation and the roles of integrins, cadherins, and calcium, we used rKSHV.219-infected primary oral keratinocytes in submerged, suspension, and direct suprabasal plating, models of differentiation. We found that early keratinocyte differentiation did not activate lytic KSHV in cells attached to a substratum, with activation only occurring in suprabasal cells. Temporally, KSHV lytic expression occurred between the expression of early and late differentiation markers. Keratinocytes differentiated in suspension culture, which mimics substratum loss that occurs with stratification, activated lytic KSHV. This lytic activation was inhibited by integrin engagement, showing that integrins are a control point for KSHV reactivation. A role for cadherins was not found. Elevated extracellular calcium was necessary, but not sufficient, for lytic activation.

Gene expression profiling by DNA microarrays and its application to dental research

UNLABELLED DNA microarray technology has been used for genome-wide gene expression studies that incorporate molecular genetics and computer science skills on massive levels. The technology permits the simultaneous analysis of tens of thousands of genes for the purposes of gene discovery, disease diagnosis. improved drug development, and therapeutics tailored to specific disease processes. OBJECTIVE In this review, the two most common microarray technologies and their potential application to dental research will be discussed. The authors review current articles pertaining to the technologies and analysis of mRNA expression using DNA micro-arrays and its application to dental research. Since many genes contribute to normal functioning, research efforts are moving from the search for a disease specific gene to the understanding of the biochemical and molecular functioning of a variety of genes and how complicated networks of interaction can lead to a disease state, such as oral cancer. With the incorporation of DNA micro-array based research, we can look forward to more accurate diagnosis and surgical treatment/drug-delivery therapy based on an individual patients genetic profile.

Content-specific auditing of a large scale anatomy ontology

Biomedical ontologies are envisioned to be usable in a range of research and clinical applications. The requirements for such uses include formal consistency, adequacy of coverage, and possibly other domain specific constraints. In this report we describe a case study that illustrates how application specific requirements may be used to identify modeling problems as well as data entry errors in ontology building and evolution. We have begun a project to use the UW Foundational Model of Anatomy (FMA) in a clinical application in radiation therapy planning. This application focuses mainly (but not exclusively) on the representation of the lymphatic system in the FMA, in order to predict the spread of tumor cells to regional metastatic sites. This application requires that the downstream relations associated with lymphatic system components must only be to other lymphatic chains or vessels, must be at the appropriate level of granularity, and that every path through the lymphatic system must terminate at one of the two well known trunks of the lymphatic system. It is possible through a programmable query interface to the FMA to write small programs that systematically audit the FMA for compliance with these constraints. We report on the design of some of these programs, and the results we obtained by applying them to the lymphatic system. The algorithms and approach are generalizable to other network organ systems in the FMA such as arteries and veins. In addition to illustrating exact constraint checking methods, this work illustrates how the details of an application may reflect back a requirement to revise the design of the ontology itself.

Evaluation of a Minimally Disruptive Treatment Protocol for Frontal Sinus Fractures

Importance Despite common goals of frontal sinus fracture treatment (restoring forehead contour and creating a safe sinus), there remains significant variability in evaluation and treatment. Objective To describe our experience with a minimally disruptive treatment protocol for the treatment of frontal sinus fractures. Design, Setting, and Participants Analysis of prospectively collected data from 2010 through 2015 at a level 1 trauma center. All patients with frontal sinus fractures treated with our protocol from January 2010 to December 2015. Patients with poor follow-up and/or incomplete medical records were excluded from analysis. Main Outcomes and Measures Presence of an aerated frontal sinus and aesthetically acceptable forehead contour. Secondary outcome measures were complications related to frontal sinus fractures. Results A total of 39 patients were treated under our minimally disruptive protocol, and 25 patients were included in the study; 18 (72%) were male and 7 (28%) were female. Their ages ranged from 6 to 62 years. After review, 22 patients had both clinical and radiographic follow-up. No patients underwent immediate frontal sinus repair. Five of 22 patients underwent surgery for indications other than their frontal sinus fracture: 1 of 5 patients underwent immediate surgical repair due to bilateral LeFort fractures, and 4 of 5 underwent delayed surgery due to nasal polyps (1 patient), scar revision (1 patient), and concomitant LeFort fractures (2 patients). Two of 22 patients (9%) underwent frontal sinus repair after outpatient surveillance due to persistent cerebrospinal fluid leak (1 patient) and orbital roof fracture (1 patient). The remaining 20 patients were treated nonoperatively, and 19 of 20 (95%) had spontaneous improvement in opacification and/or contour deformity. Twelve of 20 patients (60%) had improvement or resolution in both. One patient had ongoing partial opacification and deformity at the 3-month follow-up but was asymptomatic and had bony contour that was aesthetically acceptable to the patient. There were no complications. The median of all follow-up was 3 months. Conclusions and Relevance Frontal sinus fractures treated nonoperatively had a high rate of spontaneous ventilation and bony autoreduction with aesthetically acceptable frontal bone remodeling. There were no complications in the nonoperative group. The initial results of this study support further study of the safety and efficacy of a minimally disruptive protocol for frontal sinus fractures. Level of Evidence 4.

Automated delineation of regional target volumes for patients with head and neck cancer treated conformally

Purpose/Objective: Despite advances in radiotherapy planning and delivery systems, conformal head and neck radiotherapy continues to require labor-intensive target delineation on axial slices of a treatment-planning CT scan. In addition to being time-consuming and complex, manual contouring is also potentially inaccurate. The purpose of this study was to design a computer algorithm that could accurately and automatically contour the cervical lymph node levels (Ia-V) for patients receiving conformal radiotherapy/IMRT.

Automated Surgical Approach Planning for Complex Skull Base Targets: Development and Validation of a Cost Function and Semantic At-las:

Successful multidisciplinary treatment of skull base pathology requires precise preoperative planning. Current surgical approach (pathway) selection for these complex procedures depends on an individual surgeon’s experiences and background training. Because of anatomical variation in both normal tissue and pathology (eg, tumor), a successful surgical pathway used on one patient is not necessarily the best approach on another patient. The question is how to define and obtain optimized patient-specific surgical approach pathways? In this article, we demonstrate that the surgeon’s knowledge and decision making in preoperative planning can be modeled by a multiobjective cost function in a retrospective analysis of actual complex skull base cases. Two different approaches— weighted-sum approach and Pareto optimality—were used with a defined cost function to derive optimized surgical pathways based on preoperative computed tomography (CT) scans and manually designated pathology. With the first method, surgeon’s preferences were input as a set of weights for each objective before the search. In the second approach, the surgeon’s preferences were used to select a surgical pathway from the computed Pareto optimal set. Using preoperative CT and magnetic resonance imaging, the patient-specific surgical pathways derived by these methods were similar (85% agreement) to the actual approaches performed on patients. In one case where the actual surgical approach was different, revision surgery was required and was performed utilizing the computationally derived approach pathway.