Emily Light

OBJECTIVES/HYPOTHESIS: Human papillomavirus-16 (HPV-16)-associated carcinoma of the oropharynx has a favorable prognosis. Such patients have elevated CD8+ T-lymphocyte levels that correlate with response to chemotherapy and survival. Tumor-infiltrating lymphocyte (TIL) subpopulations were assessed in pretreatment biopsies from a prospective patient cohort to determine if TIL subsets differed by HPV status, clinical factors, or patient outcome or correlated with peripheral blood T-cell levels. STUDY DESIGN: Retrospective immunological correlative study of patients entered in a prospective Phase 2 clinical trial. METHODS: Measured were CD8, CD4, CD68, and Treg (FoxP3) lymphocytes by immunohistochemistry in a tissue microarray created from patients (n=46) with advanced oropharyngeal cancer. Correlations with peripheral blood levels, HPV status, expression of epidermal growth factor receptor (EGFR), clinical tumor, and patient characteristics and outcome were determined. Median follow-up was 6.6 years. RESULTS: HPV-16-positive patients had improved survival (P=.016). Degree of T-cell infiltration did not differ by HPV status but was significantly related to disease-specific survival (DSS) and overall survival (OS). Even after adjusting for HPV status, we found that CD8, FoxP3, and total T cells were significantly associated with DSS (P=.0236, P=.0040, and P=.0197, respectively) and OS (P=.0137, P=.0158, and P=.0115, respectively). Less T-cell infiltration (P=.0130) and CD4 cells in particular (P=.0792) were associated with higher EGFR expression. CONCLUSIONS: Improved outcomes are associated with increased TILs independent of HPV status and suggest the local immune response may be more related to factors such as tumor size, EGFR expression, or performance status than HPV status. Further study of larger numbers of patients and infiltrates combined with functional analysis of individual subsets may be necessary to detect significant differences in local immunity in HPV-16-related cancers.

Diabetic neuropathy is a severe complication of long-standing diabetes and one of the major etiologies of neuropathic pain. Diabetes is associated with an increased formation of reactive oxygen species and the electrophilic dicarbonyl compound methylglyoxal (MG). Here we show that MG stimulates heterologously expressed TRPA1 in CHO cells and natively expressed TRPA1 in MDCK cells and DRG neurons. MG evokes [Ca(2+)]i-responses in TRPA1 expressing DRG neurons but is without effect in neurons cultured from Trpa1(-/-) mice. Consistent with a direct, intracellular action, we show that methylglyoxal is significantly more potent as a TRPA1 agonist when applied to the intracellular face of excised membrane patches than to intact cells. Local intraplantar administration of MG evokes a pain response in Trpa1(+/+) but not in Trpa1(-/-) mice. Furthermore, persistently increased MG levels achieved by two weeks pharmacological inhibition of glyoxalase-1 (GLO-1), the rate-limiting enzyme responsible for detoxification of MG, evokes a progressive and marked thermal (cold and heat) and mechanical hypersensitivity in wildtype but not in Trpa1(-/-) mice. Our results thus demonstrate that TRPA1 is required both for the acute pain response evoked by topical MG and for the long-lasting pronociceptive effects associated with elevated MG in vivo. In contrast to our observations in DRG neurons, MG evokes indistinguishable [Ca(2+)]i-responses in pancreatic β-cells cultured from Trpa1(+/+) and Trpa1(-/-) mice. In vivo, the TRPA1 antagonist HC030031 impairs glucose clearance in the glucose tolerance test both in Trpa1(+/+) and Trpa1(-/-) mice, indicating a non-TRPA1 mediated effect and suggesting that results obtained with this compound should be interpreted with caution. Our results show that TRPA1 is the principal target for MG in sensory neurons but not in pancreatic β-cells and that activation of TRPA1 by MG produces a painful neuropathy with the behavioral hallmarks of diabetic neuropathy.

OBJECTIVE: to determine whether the favorable outcome associated with human papillomavirus (HPV) 16-positive oropharyngeal cancer is related to a patient's adaptive immunity. SETTING: academic medical center. PATIENTS: forty-seven of 66 previously untreated patients (6 of 20 patients with stage III and 41 of 46 with stage IV cancer) in a prospective clinical trial of chemoradiotherapy. INTERVENTION: all patients were treated with a single course of neoadjuvant chemotherapy followed by either surgery (for nonresponders) or chemoradiotherapy. MAIN OUTCOME MEASURES: pretreatment levels (percentages and absolute counts) of CD3, CD4, CD8, natural killer, and B cells and overall white blood cell counts were measured by flow cytometry. Correlations of subsets with HPV-16 status, tumor subsite, cancer stage, T class, N class, smoking status, performance status, sex, response to chemoradiotherapy, p53 mutation type, epidermal growth factor receptor expression, and disease-specific and overall survival were determined. RESULTS: after a median follow-up of 6.6 years, improved survival was associated with an elevated percentage of CD8 cells (P = .04), a low CD4:CD8 ratio (P = .01), low epidermal growth factor receptor expression (P = .002), and HPV status (P = .02). The percentage of CD8 cells was significantly higher (P = .04) and the CD4:CD8 ratio was significantly lower (P = .02) in HPV-16-positive patients. A higher percentage of CD8 cells was associated with response to induction chemotherapy (P = .02) and complete tumor response after chemoradiotherapy (P = .045). CONCLUSION: these findings confirm previous correlations of outcome with circulating CD8 cell levels and support the conjecture that improved adaptive immunity may play a role in the favorable prognosis of patients with HPV-16-positive cancers.

OBJECTIVES: To identify significant clinical and pathological predictors of survival in mucosal melanoma of the head and neck. DESIGN: Retrospective case series. We reviewed cases of mucosal melanoma of the head and neck from a prospectively collected database after institutional review board approval. SETTING: A single academic institution. PATIENTS: Fifty-two patients with mucosal melanoma of the head and neck. RESULTS: With a median follow-up of 97 months, the median overall survival was 52 months, with a 5-year overall survival of 38%. The median disease-free survival was 15 months, with a 5-year disease-free survival of 22%. Younger age (P = .02), lower T status (P = .003), and lower American Joint Committee on Cancer stage (P < .001) were associated with better overall survival. Positive surgical margins predicted poorer overall survival (P = .01), but patients who required reexcision to achieve negative margins had outcomes that were not significantly different from those with initially negative surgical margins (P = .71). Sex, smoking history, and primary site did not affect disease-free or overall survival. Adjuvant radiotherapy and/or chemotherapy did not predict improved outcomes. Fewer mitoses (P = .02) and the absence of ulceration (P = .01) predicted improved overall survival. CONCLUSIONS: Our experience confirms the utility of current staging systems in predicting outcomes of mucosal melanoma of the head and neck and stresses the importance of achieving negative surgical margins. Pathologically, fewer mitoses and the absence of ulceration predict better outcomes and should be reported as part of routine histological profiles of mucosal melanoma. Further studies are necessary to change the paradigm of care for this rare and deadly disease.