Modeling epithelial homeostasis and perturbation in three-dimensional human esophageal organoids.

Background: Esophageal organoids from a variety of pathologies including cancer are grown in Advanced Dulbecco's Modified Eagle Medium-Nutrient Mixture F12 (hereafter ADF). However, the currently available ADF-based formulations are suboptimal for normal human esophageal organoids, limiting the ability to compare normal esophageal organoids with those representing a given disease state. Methods: We have utilized immortalized normal human esophageal epithelial cell (keratinocyte) lines EPC1 and EPC2 and endoscopic normal esophageal biopsies to generate three-dimensional (3D) organoids. To optimize ADF-based medium, we evaluated the requirement of exogenous epidermal growth factor (EGF) and inhibition of transforming growth factor-(TGF)-ß receptor-mediated signaling, both key regulators of proliferation of human esophageal keratinocytes. We have modeled human esophageal epithelial pathology by stimulating esophageal 3D organoids with interleukin (IL)-13, an inflammatory cytokine, or UAB30, a novel pharmacological activator of retinoic acid signaling. Results: The formation of normal human esophageal 3D organoids was limited by excessive EGF and intrinsic TGFß receptor-mediated signaling. In optimized HOME0, normal human esophageal organoid formation was improved, whereas IL-13 and UAB30 induced epithelial changes reminiscent of basal cell hyperplasia, a common histopathologic feature in broad esophageal disease conditions including eosinophilic esophagitis. Conclusions: HOME0 allows modeling of the homeostatic differentiation gradient and perturbation of the human esophageal epithelium while permitting a comparison of organoids from mice and other organs grown in ADF-based media.

Inhaled fosamprenavir for laryngopharyngeal reflux: Toxicology and fluid dynamics modeling.

Objectives: Approximately 25% of Americans suffer from laryngopharyngeal reflux (LPR), a disease for which no effective medical therapy exists. Pepsin is a predominant source of damage during LPR and a key therapeutic target. Fosamprenavir (FOS) inhibits pepsin and prevents damage in an LPR mouse model. Inhaled FOS protects at a lower dose than oral; however, the safety of inhaled FOS is unknown and there are no inhalers for laryngopharyngeal delivery. A pre-Good Lab Practice (GLP) study of inhaled FOS was performed to assess safety and computational fluid dynamics (CFD) modeling used to predict the optimal particle size for a laryngopharyngeal dry powder inhaler (DPI). Methods: Aerosolized FOS, amprenavir (APR), or air (control) were provided 5 days/week for 4 weeks (n = 6) in an LPR mouse model. Organs (nasal cavity, larynx, esophagus, trachea, lung, liver, heart, and kidney) were assessed by a pathologist and bronchoalveolar lavage cytokines and plasma cardiotoxicity markers were assessed by Luminex assay. CFD simulations were conducted in a model of a healthy 49-year-old female. Results: No significant increase was observed in histologic lesions, cytokines, or cardiotoxicity markers in FOS or APR groups relative to the control. CFD predicted that laryngopharyngeal deposition was maximized with aerodynamic diameters of 8.1-11.5 µm for inhalation rates of 30-60 L/min. Conclusions: A 4-week pre-GLP study supports the safety of inhaled FOS. A formal GLP assessment is underway to support a phase I clinical trial of an FOS DPI for LPR. Level of Evidence: NA.

Using Bland-Altman Analysis to Identify Appropriate Clonogenic Assay Colony Counting Techniques.

OBJECTIVE: Determine the interchangeability of various methods utilized for counting colonies in clonogenic assays. METHODS: Clonogenic assays of 2 head and neck cancer cell lines were counted through 4 different counting modalities: Manual counting pen, via microscope, 1 publicly available automated algorithm, and a semiautomated algorithm presented by the authors. Each method counted individual wells (N = 24). Pen and microscopic counts were performed by 2 observers. Parameters included both low-growth (<150 colonies/well) and high-growth (>150 colonies/well) cell lines. Correlational and Bland-Altman analyses were performed using SPSS software. RESULTS: Interobserver manual pen count correlation R2 value in both growth conditions was 0.902; controlling for only low-growth conditions decreased R2 to 0.660. Correlation of microscopic versus pen counts R2 values for observers 1 and 2 were 0.955 and 0.775, respectively. Comparing techniques, Bland-Altman revealed potential bias with respect to the magnitude of measurement (P < .001) for both observers. Correlation of microscopic counts for both interobserver (R2 = 0.902) and intraobserver (R2 = 0.916) were analyzed. Bland-Altman revealed no bias (P = .489). Automated versus microscopic counts revealed no bias between methodologies (P = .787) and a lower correlation coefficient (R2 = 0.384). Semiautomated versus microscopic counts revealed no bias with respect to magnitude of measurement for either observer (P = .327, .229); Pearson correlation was 0.985 (R2 = 0.970) and 0.965 (R2 = 0.931) for observer 1 and 2. Semiautomated versus manual pen colony counts revealed a significant bias with respect to magnitude of measurement (P < .001). CONCLUSION: Counting with a manual pen demonstrated significant bias when compared to microscopic and semiautomated colony counts; 2 methods were deemed to be interchangeable. Thus, training algorithms based on manual counts may introduce this bias as well. Algorithms trained to select colonies based on size (pixels2) and shape (circularity) should be prioritized. Solely relying on Bland-Altman or correlational analyses when determining method interchangeability should be avoided; they rather should be used in conjunction.

Potential Roles of Activin in Head and Neck Squamous Cell Carcinoma Progression and Mortality.

BACKGROUND/AIM: Activin, a member of the TGF-ß super family of cytokines, is involved in head and neck squamous cell carcinoma (HNSCC). This study examined the constituents of the activin axis in order to further elucidate the role of activin A in HNSCC progression. MATERIALS AND METHODS: Immunohistochemistry (IHC), reverse transcription polymerase chain reaction (RT-PCR), MTT, and matrigel invasion assays, in addition to analysis of the tumor cancer genome atlas (TCGA), were employed. RESULTS: IHC in HNSCC and oral leukoplakia (OPL) lesions demonstrated increased expression of the inhibin subunit ßA (INHBA) (p<0.0001), as well as activin receptor type IB (ACVR1B) (p<0.0032) compared to normal mucosa. TCGA analysis revealed increased INHBA expression was associated with lymph node positive tumors (p=0.024), decreased overall survival (p=0.0167), and decreased promoter methylation (p<0.0001). Concomitant up-regulated expression of gene pathways strongly correlated with INHBA expression demonstrated further deleterious effects on survival (p<0.0148). CONCLUSION: Activin may be an important component of early carcinogenesis in OPL and HNSCC with unfavorable effects on clinical end-points such as survival.

Metabolic and Metabolomic Effects of Metformin in Murine Model of Pulmonary Adenoma Formation.

Epidemiologic studies of diabetic patients treated with metformin identified significantly lower incidences of cancer. From this, there is growing interest in the use of metformin to treat and prevent cancer. Studies have investigated chemopreventive mechanisms including alterations in calorie intake, cancer metabolism, and cell signaling. Repurposing the drug is challenging due to its metabolic effects and non-uniform effects on different types of cancer. In our previously published studies, we observed that benzo[a]pyrene treated mice receiving metformin significantly reduced lung adenomas; however, mice had reduced weight gain. In this study, we compared chemoprevention diets with and without metformin to evaluate the effects of diet vs. effects of metformin. We also performed tandem mass spectrometry on mouse serum to assess metabolomic alterations associated with metformin treatment. In metformin cohorts, the rate of weight gain was reduced, but weights did not vary between diets. There was no weight difference between diets without metformin. Interestingly, caloric intake was increased in metformin treated mice. Metabolomic analysis revealed metabolite alterations consistent with metformin treatment. Based on these results, we conclude that previous reductions in lung adenomas may have been occurred from anticancer effects of metformin rather than a potentially toxic effect such as calorie restriction.

Oral and Inhaled Fosamprenavir Reverses Pepsin-Induced Damage in a Laryngopharyngeal Reflux Mouse Model.

OBJECTIVE: More than 20% of the US population suffers from laryngopharyngeal reflux. Although dietary/lifestyle modifications and alginates provide benefit to some, there is no gold standard medical therapy. Increasing evidence suggests that pepsin is partly, if not wholly, responsible for damage and inflammation caused by laryngopharyngeal reflux. A treatment specifically targeting pepsin would be amenable to local, inhaled delivery, and could prove effective for endoscopic signs and symptoms associated with nonacid reflux. The aim herein was to identify small molecule inhibitors of pepsin and test their efficacy to prevent pepsin-mediated laryngeal damage in vivo. METHODS: Drug and pepsin binding and inhibition were screened by high-throughput assays and crystallography. A mouse model of laryngopharyngeal reflux (mechanical laryngeal injury once weekly for 2 weeks and pH 7 solvent/pepsin instillation 3 days/week for 4 weeks) was provided inhibitor by gavage or aerosol (fosamprenavir or darunavir; 5 days/week for 4 weeks; n = 3). Larynges were collected for histopathologic analysis. RESULTS: HIV protease inhibitors amprenavir, ritonavir, saquinavir, and darunavir bound and inhibited pepsin with IC50 in the low micromolar range. Gavage and aerosol fosamprenavir prevented pepsin-mediated laryngeal damage (i.e., reactive epithelia, increased intraepithelial inflammatory cells, and cell apoptosis). Darunavir gavage elicited mild reactivity and no discernable protection; aerosol protected against apoptosis. CONCLUSIONS: Fosamprenavir and darunavir, FDA-approved therapies for HIV/AIDS, bind and inhibit pepsin, abrogating pepsin-mediated laryngeal damage in a laryngopharyngeal reflux mouse model. These drugs target a foreign virus, making them ideal to repurpose. Reformulation for local inhaled delivery could further improve outcomes and limit side effects. LEVEL OF EVIDENCE: NA. Laryngoscope, 133:S1-S11, 2023.

Oral Premalignant and Malignant Lesions in Fanconi Anemia Patients.

OBJECTIVE: There is a lack of data supporting cancer surveillance in pediatric Fanconi Anemia patients. We sought to describe the rates of upper aerodigestive lesions and malignancy in this population to augment current management guidelines. METHODS: A retrospective cohort study of patients with Fanconi Anemia from a quaternary referral center between 2007-2021 was completed for head and neck cancer risk. RESULTS: One hundred and five FA patients were reviewed. Average age at presentation was 11.3 years old and 90.5% of patients underwent hematopoietic stem cell transplant (HSCT). A total of 8.6% of patients had leukoplakia or erythroplakia and 3.8% developed malignancy. The standardized incidence ratio of head and neck malignancy was 483.8. Patients presented with leukoplakia and malignancy at an average age of 14.6 and 25.1 years old, respectively. Malignancies were aggressive and marked by recurrence. There were no premalignant or malignant lesions found on flexible laryngoscopy. This series represents the largest longitudinal series of pediatric FA head and neck lesions. CONCLUSIONS: Fanconi Anemia patients should begin screening for head and neck cancer at age 10 or after HSCT. LEVEL OF EVIDENCE: Level 4 Laryngoscope, 133:1745-1748, 2023.

Observations of increased gastroesophageal reflux symptomology in an anhydrous ammonia exposed population.

OBJECTIVE: This case series describes a cohort of patients exposed to anhydrous ammonia vapors with clinical findings of laryngopharyngeal reflux (LPR). The study characterizes the identification of LPR as a consequence of vapor inhalation and the utility of PPI therapy in LPR secondary to inhalational ammonia exposure. METHODS: This is a case series of 15 patients exposed to anhydrous ammonia from a single chemical spill who experienced LPR several months after exposure. Symptoms of LPR were assessed at their initial consultation and by phone at least 30 days after treatment with low-dose PPI or diet modification. At this visit, patients underwent complete head and neck examination and flexible direct laryngoscopy. RESULTS: 15 patients were available for analysis before and after treatment. 93.3 % experienced at least three cardinal symptoms of LPR. 66 % of these patients had at least one LPR finding on flexible laryngoscopy. 73 % were treated with daily standard dose PPI, and 82 % of these patients experienced reduction of symptoms after 30 days of PPI treatment. Four of 15 patients were not taking the PPI as prescribed, and only one of these patients had resolution of LPR symptoms. CONCLUSION: We conclude that there is an association between anhydrous ammonia exposure and the development of LPR symptoms. In this study, treatment with PPIs was successful in reducing symptoms for most patients, and patients who did not receive PPIs experienced symptoms for a longer time.

Effects of methylene blue photodynamic therapy on oral carcinoma and leukoplakia cells.

Objective: Methylene blue (MB) is a readily available and affordable substrate that can be used as a photosensitizer for photodynamic therapy (PDT). The objective of this study was to determine if PDT with MB can downregulate matrix metalloproteinases (MMPs) related to oral carcinoma. Methods: Cell cultures of oral squamous cell carcinoma (CA-9-22), oral leukoplakia (MSK-Leuk1), and immortalized keratinocytes (Rhek-1A) were photosensitized with MB and treated with PDT. MMP-9 gene expression was interrogated via qRT-PCR. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to confirm the efficacy of MB PDT. Results: MMP-9 gene expression was found to be significantly decreased in oral carcinoma, leukoplakia, and immortalized keratinocytes with use of MB PDT. Conclusion: This work demonstrates that MB-mediated PDT can downregulate MMPs which are critical to the invasion and metastasis of oral cancer. These results suggest that MB PDT could be a clinically significant and cost-effective treatment for oral leukoplakia and carcinoma. Level of Evidence: NA.

Medical scribes improve documentation consistency and efficiency in an otolaryngology clinic.

OBJECTIVE: Scribes in medical practice enable more efficient documentation requirements but insufficient analyses have occurred to fully evaluate their efficacy in otolaryngology. We analyzed pre/post metrics of scribe implementation that may aid practitioners in determining feasibility for use in their practices. METHODS: 1808 patient charts were analyzed in The Epic Electronic Medical Record system (EMR) (903 pre and 905 post scribe implementation). We measured: clinic volumes, time saved in documentation, chart billing level, and lag days of chart closure. RESULTS: Patient volumes increased by 3.02% with an 11-17% decrease in time spent in clinic/day and lag days for billing. The distribution of visits for new patients was 17.75% level 2, 51.45% level 3, 29.71% level 4 before the scribe and was 6.83% level 2, 89.21% level 3, 3.96% level 4 after the scribe. For established patients it was 3.97% level 2, 84.92% level 3, 8.93% level 4 before and 0.34% level 2, 91.76% level 3, 7.73% level 4 after. The change in level of documentation for established and new patients pre and post scribe implementation was not statistically significant (p = 0.821, 0.063, respectively). Charts were closed within 0 to 7 days with the implementation of a scribe instead of 7-21 days when awaiting dictations for transcription. CONCLUSIONS: The implementation of a scribe in an academic otolaryngology clinic facilitated more rapid completion of documentation while decreasing provider hours/day in clinic. We feel the analysis can be generalized to otolaryngology practitioners in general and the data structures we implemented are usable for others.

Large cell neuroendocrine carcinoma originating in the subglottic larynx.

Large cell neuroendocrine carcinoma (LCNEC) of the larynx is an exceedingly rare cancer of the head and neck that is difficult to diagnose. Few case reports of laryngeal LCNEC exist within the literature, and it was not until recently that LCNEC was recognized as a discrete subtype of neuroendocrine carcinoma. Given its recent recognition as a distinct subtype, histologic characteristics distinguishing LCNEC from other poorly differentiated carcinomas remain under investigation. Various reports have shown genetic alterations such as p53 and/or p16 overexpression, which are typically associated with infection by human papilloma virus (HPV). However, some reports have shown p53 and/or p16 overexpression in HPV negative samples. In this case, we discuss a 67-year-old patient with a history of extensive alcohol and tobacco use with a newly diagnosed T4N0M0, high grade, LCNEC of the subglottic larynx. Tumor pathology demonstrated positive staining for typical neuroendocrine (NE) markers like synaptophysin and chromogranin A; however, there was diffuse CK34ßE12 and p16 expression. LCNEC is a newly classified subtype of poorly differentiated neuroendocrine (NE) tumors, and the diagnosis requires consideration of the clinical presentation, microscopic features, and immunostaining markers.

Patients with oral preneoplastic lesions and integration of dental pathology referrals.

PURPOSE: Oral cancers lack standardized monitoring systems. Our institution has developed an active surveillance system which provides detailed monitoring and follow up of patients with oral preneoplastic lesions (OPL). We examined a historic cohort of patients with OPL seen by regional dental professionals and a current cohort of clinic patients. The major aim was to examine follow up practices for biopsy proven dysplasia to gauge appropriateness of an active monitoring system for oral carcinoma. MATERIALS AND METHODS: Questionnaires regarding patients with OPL were sent to 285 dentists who had requested oral pathology services from our institution. The follow up practices of 141 dentists were evaluated for patients with OPL. We then examined our current clinic referral patterns for the number of dental referrals after the creation of an oral carcinoma active surveillance clinic. RESULTS: There were 76.5% (108/141) of patients who received follow up after diagnosis of preneoplastic oral lesions with 14.1% who underwent repeat biopsy. There was a malignant transformation rate of 11.3% including transformation of 42.8% of severe dysplasias into carcinoma within 2 years. After establishment of a dental referral clinic, 21.8% of tumor visits in a six-week period were referred from the regional dental community. CONCLUSIONS: A high rate of transformation of OPL to cancer in this cohort may support a role for joint dental and otolaryngology surveillance of dysplasia with longitudinal follow up.

Preclinical evidence for pioglitazone and bexarotene combination in oral cancer chemoprevention.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) requires new treatments and targeted approaches to improve survival. The peroxisome proliferator-activated receptor γ (PPARγ) and retinoic X receptor alpha (RXRα) nuclear receptor pathways may be targetable with repurposed Food and Drug Administration (FDA)-approved agents for prevention and treatment. METHODS: Oral cancer and leukoplakia cell lines were treated with the PPARγ agonist (pioglitazone) and RXRα activator (bexarotene). PPARγ activation, cellular proliferation, apoptosis activity and phenotype, including the pharmacodynamic marker, involucrin (IVL), were subsequently analyzed using a reporter gene assay, genomic data, MTT assay and western blot. RESULTS: Microarray analysis of HNSCC tumor versus normal tissue shows IVL expression is significantly increased in normal tissue compared to HNSCC tumors (p < 0.0001). In MSK Leuk1 and CA 9-22 cell lines, pioglitazone increases PPARγ DNA binding activity and IVL promoter activity in a dose dependent manner (p < 0.01 and p < 0.0001). Combination treatment with pioglitazone and bexarotene increases PPARγ DNA binding activity and IVL promoter activity (p < 0.01 and p < 0.0001). MTT analysis shows decreases in cell proliferation when cells are treated with pioglitazone and bexarotene. Decreases in cell proliferation are significant to at least p < 0.05 for all combination versus single agent treatments. Western blot on whole-cell lysate from cells treated with pioglitazone and bexarotene alone or in combination for IVL showed increased protein levels with combination treatment. CONCLUSIONS: Targeting the PPARγ/RXRα heterodimer with pioglitazone and bexarotene was effective in this preclinical project. This was functional in both preneoplastic and oral cancer cell lines. A better understanding of the molecular mechanism on downstream effects on cellular proliferation could potentially have implications clinically, both in oral preneoplasia and possibly head and neck cancer; however, more research needs to be done to explore the potential these medications have in chemoprevention.

An active surveillance program in oral preneoplasia and translational oncology benefit.

OBJECTIVE: We desired to establish an active surveillance clinic for head and neck cancer. In this review we examined. METHODS: We examined the natural history of human oral carcinogenesis, the types of preneoplastic lesions, and efforts at oral chemoprevention over the past decades for presentation here. RESULTS: We established a clinic and program for patients with oral premalignant lesions approximately over 15 years ago based on an unmetneed for this service. We have completed over 4000 outpatient visits for this cohort and have a place for referrals of difficult oral lesions. We have leveraged this population for multiple federally funded trials on oral cancer prevention as well as specimen banking. CONCLUSION: There is need for routine active surveillance for oral preneoplastic conditions in patients at high risk for conversion to cancer. There are no effective durable treatment or preventions for these individuals and we have attempted to fill this unmet need with our program.

Inhibition of mTOR signaling and clinical activity of metformin in oral premalignant lesions.

BACKGROUNDThe aberrant activation of the PI3K/mTOR signaling circuitry is one of the most frequently dysregulated signaling events in head and neck squamous cell carcinoma (HNSCC). Here, we conducted a single-arm, open-label phase IIa clinical trial in individuals with oral premalignant lesions (OPLs) to explore the potential of metformin to target PI3K/mTOR signaling for HNSCC prevention.METHODSIndividuals with OPLs, but who were otherwise healthy and without diabetes, underwent pretreatment and posttreatment clinical exam and biopsy. Participants received metformin for 12 weeks (week 1, 500 mg; week 2, 1000 mg; weeks 3-12, 2000 mg daily). Pretreatment and posttreatment biopsies, saliva, and blood were obtained for biomarker analysis, including IHC assessment of mTOR signaling and exome sequencing.RESULTSTwenty-three participants were evaluable for response. The clinical response rate (defined as a ≥50% reduction in lesion size) was 17%. Although lower than the proposed threshold for favorable clinical response, the histological response rate (improvement in histological grade) was 60%, including 17% complete responses and 43% partial responses. Logistic regression analysis revealed that when compared with never smokers, current and former smokers had statistically significantly increased histological responses (P = 0.016). Remarkably, a significant correlation existed between decreased mTOR activity (pS6 IHC staining) in the basal epithelial layers of OPLs and the histological (P = 0.04) and clinical (P = 0.01) responses.CONCLUSIONTo our knowledge this is the first phase II trial of metformin in individuals with OPLs, providing evidence that metformin administration results in encouraging histological responses and mTOR pathway modulation, thus supporting its further investigation as a chemopreventive agent.TRIAL REGISTRATIONNCT02581137FUNDINGNIH contract HHSN261201200031I, grants R01DE026644 and R01DE026870.

Genomic Database Analysis for Head and Neck Cancer Prevention Targets: MTOR Signal Transduction Pathway.

BACKGROUND: Type II diabetes agents have anticancer effects on head and neck squamous cell carcinoma (HNSCC). The mechanistic target of rapamycin (MTOR) pathway represents a putative target. MATERIALS AND METHODS: We interrogated an Affymetrix HNSCC dataset for MTOR-related gene expression. RESULTS: MTOR expression itself was unchanged, but various related genes demonstrated differential expression. Pathway promoters ras homolog (RHEB), MTOR-associated protein (MLST8), and ribosomal protein S6 kinase B1 (RPS6KB1) were up-regulated. Expression of growth suppressors tuberous sclerosis complex 2 (TSC2), programmed cell death 4 (PDCD4), and BCL2 apoptosis regulator-associated agonist of cell death (BAD) were reduced in HNSCC. Upstream, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), AKT serine/threonine kinase 1 (AKT1), and phosphatase and tensin homolog (PTEN) were up-regulated in cancer. CONCLUSION: Several MTOR pathway promoters and tumor suppressors were found to be differentially expressed, favoring MTOR pathway up-regulation in HNSCC. Genomic databases can be interrogated to identify intervention targets and endpoints in HNSCC trials.

Retinoids Augment Thiazolidinedione PPARγ Activation in Oral Cancer Cells.

BACKGROUND/AIM: Head and neck squamous cell carcinoma affects nearly 500,000 people annually. Augmenting PPARγ functional activation is linked with multiple anti-carcinogenic processes in aerodigestive cell lines and animal models. PPARγ/RXRα heterodimers may be key partners in this activation. MATERIALS AND METHODS: CA 9-22 and NA cell lines were treated with the PPARγ agonist ciglitazone and/or the RXRα agonist 9-cis-retinoic acid. PPARγ functional activation, cellular proliferation, apoptosis activity, and phenotype were subsequently analyzed. RESULTS: Ciglitazone and 9-cis-retinoic acid independently activated PPARγ and down-regulated the carcinogenic phenotype in vitro. Combination treatment significantly augmented these effects, further decreasing proliferation (p<0.0001), and increasing PPARγ functional activation (p<0.0001), apoptosis (p<0.05), and adipocyte differentiation markers (p<0.0001). CONCLUSION: The efficacy of the combination of ciglitazone and 9-cis-retinoic acid afforded lowering treatment concentrations while maintaining desired therapeutic outcomes, optimistically supporting the feasibility and practicality of this novel treatment option.

Effects of PPAR-γ agonists on oral cancer cell lines: Potential horizons for chemopreventives and adjunctive therapies.

BACKGROUND: Peroxisome proliferator-activated receptor-gamma (PPAR-γ) activators have anti-cancer effects. Our objective was to determine the effect of PPAR-γ ligands 15-deoxy-D12,14 -Prostaglandin J2 (15-PGJ2 ) and ciglitazone on proliferation, apoptosis, and NF-κB in human oral squamous cell carcinoma cell lines. METHODS: NA and CA9-22 cells were treated in vitro with 15-PGJ2 and ciglitazone. Proliferation was measured by MTT colorimetric assay and cell cycle analysis performed via flow cytometry, apoptosis by caspase-3 colorimetric assay and poly-(ADP-ribose) polymerase cleavage on Western blot, and NF-κB activation by luciferase assays. RESULTS: MTT assays demonstrated dose-dependent decreases after 15-PGJ2 treatment in both cell lines, and S-phase cell cycle arrest was also demonstrated. NF-κB luciferase reporter gene activity decreased seven- and eightfold in NA and CA9-22 cells, respectively. Caspase-3 activity increased two- and eightfold in NA and CA9-22 cells, respectively. CONCLUSIONS: Our results suggest these agents, in addition to activating PPAR-γ, can downregulate NF-κB and potentiate apoptosis in oral cancer cells.