Gregory M. Ness

Topical Application of a Mucoadhesive Freeze-Dried Black Raspberry Gel Induces Clinical and Histologic Regression and Reduces Loss of Heterozygosity Events in Premalignant Oral Intraepithelial Lesions: Results from a Multicentered, Placebo-Controlled Clinical Trial

Purpose: Approximately 30% higher grade premalignant oral intraepithelial neoplasia (OIN) lesions will progress to oral cancer. Although surgery is the OIN treatment mainstay, many OIN lesions recur, which is highly problematic for both surgeons and patients. This clinical trial assessed the chemopreventive efficacy of a natural product-based bioadhesive gel on OIN lesions. Experimental Design: This placebo-controlled multicenter study investigated the effects of topical application of bioadhesive gels that contained either 10% w/w freeze-dried black raspberries (BRB) or an identical formulation devoid of BRB placebo to biopsy-confirmed OIN lesions (0.5 g × q.i.d., 12 weeks). Baseline evaluative parameters (size, histologic grade, LOH events) were comparable in the randomly assigned BRB (n = 22) and placebo (n = 18) gel cohorts. Evaluative parameters were: histologic grade, clinical size, and LOH. Results: Topical application of the BRB gel to OIN lesions resulted in statistically significant reductions in lesional sizes, histologic grades, and LOH events. In contrast, placebo gel lesions demonstrated a significant increase in lesional size and no significant effects on histologic grade or LOH events. Collectively, these data strongly support BRBs chemopreventive impact. A cohort of very BRB-responsive patients, as demonstrated by high therapeutic efficacy, was identified. Corresponding protein profiling studies, which demonstrated higher pretreatment levels of BRB metabolic and keratinocyte differentiation enzymes in BRB-responsive lesions, reinforce the importance of local metabolism and differentiation competency. Conclusions: Results from this trial substantiate the LOH reductions identified in the pilot BRB gel study and extend therapeutic effects to significant improvements in histologic grade and lesional size. Clin Cancer Res; 20(7); 1910–24. ©2014 AACR.

THIOL REDOX MODULATION OF DOXORUBICIN MEDIATED CYTOTOXICITY IN CULTURED AIDS-RELATED KAPOSI'S SARCOMA CELLS

The chemotherapeutic, doxorubicin, is currently used empirically in the treatment of AIDS‐ related Kaposis sarcoma (AIDS‐KS). Although often employed in a chemotherapeutic cocktail (doxorubicin, bleomycin, vincristine) single‐agent therapy has recently been attempted with liposome encapsulated doxorubicin. Although doxorubicins mechanism of action against AIDS‐KS is unknown, we hypothesized that doxorubicins ability to undergo redox cycling is associated with its clinical efficacy. The current study was conducted to investigate the effects of doxorubicin on selected xenobiotic‐associated biochemical responses of three cellular populations: KS lesional cells, nonlesional cells from the KS donors, and fibroblasts obtained from HIV− aged matched men. Our results show that during doxorubicin challenge, there are strong positive correlations between cellular glutathione (GSH) levels and viability (r = 0.94), NADPH levels and viability (r = 0.93), and GSH and NADPH levels (r = 0.93), and demonstrate that as a consequence of their abilities to maintain cellular thiol redox pools HIV− donor cells are significantly less susceptible to doxorubicins cytotoxic effects relative to AIDS‐KS cells. Additional studies further supported the contribution of reduced thiols in mediating doxorubicin tolerance. While pretreatment with the GSH precursor, N‐acetylcysteine was cytoprotective for all cell groups during doxorubicin challenge, GSH depletion markedly enhanced doxorubicins cytotoxic effects. Studies to investigate the effects of a hydroxyl scavenger and iron chelator during doxorubicin challenge showed moderate cytoprotection in the AIDS‐KS cells but deleterious effects in the HIV− control cells. Inactivation of the longer lived membrane generated ROI in the cytoprotective deficient AIDS‐KS cells, as well as an impairment of endogenous defenses in the HIV− donor control cells, may account for these scavenger and chelator associated findings. In summary, our findings show that doxorubicin mediates, at least in part, its AIDS‐KS cellular cytotoxic effects by a redox related mechanism, and provides a biochemical rationale for doxorubicins clinical efficacy in AIDS‐KS treatment. J. Cell. Biochem. 73:259–277, 1999.

AIDS‐related Kaposi's sarcoma cells rapidly internalize endostatin, which co‐localizes to tropomysin microfilaments and inhibits cytokine‐mediated migration and invasion

AIDS‐related Kaposis sarcoma (KS) is the most common HIV‐related malignancy. In some respects, KS is analogous to other angioproliferative diseases, in that KS lesions are highly vascularized and promoted by inflammatory cytokines. However, unlike other cancers or inflammatory mediated vascular diseases, KS is unique in that the KS lesional cells both express and respond to the complete angiogenic cytokines vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Therefore, the angiogenic phenotype, which is crucial for cancer progression, is inherent to KS tumor cells. Due to the recognized importance of angiogenesis in cancer progression, numerous angiostatic agents are being investigated as potential therapeutic agents. One such agent is endostatin, which is a 20‐kDa carboxyl‐terminal fragment of collagen XVIII that has demonstrated potent angiostatic activities at both the in vivo and in vitro levels. Since endostatin is recognized as a potent angiostatic agent, the majority of in vitro endostatin studies have evaluated its effects on endothelial cells. Although KS cells are speculated to arise from endothelial cell precursors and KS lesions are highly vascularized, no previous studies have investigated endostatin–KS cell interactions. This present study evaluated endostatins effects on KS tumor cell: (i) signal transduction (endostatin internalization and transcription factor activation), and (ii) migration and invasion (functional activity assays and tropomysin co‐localization). Our results show that KS cells rapidly internalize endostatin and that endostatin initiates activation of the transcription activating factors nuclear factor‐κB (NF‐κB) and activating protein 1 (AP‐1). Our data also show that internalized endostatin co‐localizes to tropomysin microfilaments and acts to inhibit KS cell migration and invasion in response to the clinically relevant angiogenic cytokines VEGF and bFGF. As a consequence of its combined angiostatic and antitumorigenic activities, endostatin could provide dual therapeutic benefits for patients with mucocutaneous KS. J. Cell. Biochem. 89: 133–143, 2003. Published 2003 Wiley‐Liss, Inc.

Thiol redox modulation of tumor necrosis factor-α responsiveness in cultured AIDS-related Kaposi's sarcoma cells

Both clinical and experimental evidence indicates that AIDS‐related Kaposis sarcoma (AIDS‐KS) has a multifactorial pathogenesis with factors such as HIV viral load, latent virus induction, and opportunistic infections contributing to disease progression. However, a consistent feature that unites these apparently diverse putative etiologic agents is sustained serum elevations of pro‐inflammatory cytokines such as tumor necrosis factor‐α (TNF‐α). While virtually every cell responds to TNF‐α with gene activation, the extent of TNF‐α‐mediated cellular signaling is regulated by a delicate balance between signal activation and signal arresting events. Reactive oxygen intermediates (ROI), which are generated as a consequence of TNF‐α membrane interaction, are part of this TNF‐α‐initiated cellular activation cascade. Previous studies in our laboratory have shown that AIDS‐KS cells possess impaired oxygen intermediate scavenging capacities, thereby establishing conditions permissive for the intracellular retention of ROI. In this study, we used cellular capacity to upregulate the cytoprotective enzyme superoxide dismutase (SOD) to address the extent of cellular response to TNF‐α. Concurrent with the SOD analyses, nucleotide profiles were obtained to assess cellular bioenergetic responses during TNF‐α challenge. Proliferative growth levels of mitochondrial (Mn)SOD activities showed an activity spectrum ranging from lowest activity in AIDS‐KS cells, to intermediate levels in matched, nonlesional cells from the AIDS‐KS donors, to highest activities in HIV− normal fibroblasts. In contrast, following TNF‐α challenge, the AIDS‐KS and KS donor nonlesional cells showed a 11.89‐ and 5.86‐fold respective increase in MnSOD activity, while the normal fibroblasts demonstrated a 1.35‐fold decrease. Subsequent thiol redox modulation studies showed that only the normal fibroblast cultures showed a potentiation of TNF‐α‐mediated MnSOD upregulation following GSH depletion. In addition, provision of the GSH precursor, N‐acetylcysteine during TNF‐α challenge only diminished MnSOD activity and mitochondrial compartmentalization in the AIDS‐KS cells, a finding that likely reflects the lower levels of reduced thiols in this cellular population. Our data, which show that a perturbation in their cellular thiol redox status accentuates AIDS‐KS cellular responsiveness to TNF‐α, suggest a biochemical rationale for the recognized TNF‐α AIDS‐KS clinical correlation. J. Cell. Biochem. 68:339–354, 1998.

Improving the Medical Curriculum in Predoctoral Dental Education: Recommendations From the American Association of Oral and Maxillofacial Surgeons Committee on Predoctoral Education and Training

Dental procedures are often performed on patients who present with some level of medical fragility. In many dental schools, the exercise of taking a medical history is all too often a transcription of information to the dental chart, with little emphasis on the presurgical risk assessment and the development of a treatment plan appropriate to the medical status of the dental patient. Changes in dentistry, driven by an increasingly medically complex population of dental patients, combined with treatment advances rooted in the biomedical sciences necessitate the adaptation of our dental education to include a stronger background in systemic health. Many predoctoral educators in the American Association of Oral and Maxillofacial Surgeons (AAOMS) have expressed concern about the medical preparedness of our dental students; therefore, the AAOMS and its Committee on Predoctoral Education and Training have provided recommendations for improving the medical curriculum in predoctoral dental education, including a strengthening of training in clinical medicine and biomedical sciences, with specific recommendations for improved training of our dental students and dental faculty.

Facial Nerve Injury

Minimizing risk to the integrity of the facial nerve is a critical measure of surgical success in temporomandibular joint (TMJ) surgeries. The surgeon must have a keen understanding of the regional anatomy combined with a planned dissection to protect the facial nerve in their approach to the joint [1]. Facial nerve injury may have devastating effects on the patient esthetically and functionally due to impairment of the frontalis and/or orbicularis oculi muscles. According to Liu et al., the most current review of the literature reveals that the incidence of facial nerve injury in conjunction with open TMJ surgery ranges from 12.5 to 32% [2]. The chapter will provide a review on the anatomy of the facial nerve, procedures leading to potential injury, recognition of injury, and multiple methods of management.

Global doctor opinion versus a patient questionnaire for the outcome assessment of treated temporomandibular disorder patients.

PURPOSE Accurately assessing treatment outcomes has become increasingly important for maintaining hospital privileges. When these assessments are based on the judgment of the treating doctor, there is often an inherent positive bias. As a result, there has been increased interest in using patient-based assessments. The purpose of this study was to compare doctors and patients assessments of the outcomes of treatment in a series of patients with various temporomandibular disorders (TMDs). MATERIALS AND METHODS Fifty-two consecutive TMD patients were initially given a questionnaire designed to evaluate their pain, problems eating and sleeping, the occurrence of headache and earache, the presence of temporomandibular joint pain and/or jaw stiffness in the morning, and interference with daily activity. The patients then filled out the same questionnaire at each post-treatment visit, and the findings were compared with the baseline information. At each visit, the treating doctor also recorded a global evaluation of the patients progress as excellent, good, fair, or poor. RESULTS Comparison of the doctors global evaluation with the patients evaluation based on the questionnaire showed a discrepancy in 44% of the cases. When there was a discrepancy, the doctor scored the improvement better than the patient 54.5% of the time and worse than the patient 45.5% of the time. CONCLUSIONS The results of this study confirm the unreliability of using a global opinion by the treating doctor for outcome assessment in patients with various TMDs.