ABSTRACT
Importance: While smoking is associated with a decreased incidence of cutaneous melanoma, the association of smoking with melanoma progression and death is not well defined. Objective: To determine the association of smoking with survival in patients with early-stage primary cutaneous melanoma. Design, Setting, and Participants: This cohort study performed a post hoc analysis of data derived from the randomized, multinational first and second Multicenter Selective Lymphadenectomy Trials (MSLT-I and MSLT-II). Participants were accrued for MSLT-I from January 20, 1994, to March 29, 2002; MSLT-II, from December 21, 2004, to March 31, 2014. Median follow-up was 110.0 (IQR, 53.4-120.0) months for MSLT-I and 67.6 (IQR, 25.8-110.2) months for MSLT-II. Patients aged 18 to 75 years with clinical stages I or II melanoma with a Breslow thickness of 1.00 mm or greater or Clark level IV to V and available standard prognostic and smoking data were included. Analyses were performed from October 4, 2022, to March 31, 2023. Exposure: Current, former, and never smoking. Main Outcomes and Measures: Melanoma-specific survival of patients with current, former, and never smoking status was assessed for the entire cohort and for nodal observation and among subgroups with sentinel lymph node biopsy (SLNB)-negative and SLNB-positive findings. Results: Of 6279 included patients, 3635 (57.9%) were men, and mean (SD) age was 52.7 (13.4) years. The most common tumor location was an extremity (2743 [43.7%]), and mean (SD) Breslow thickness was 2.44 (2.06) mm. Smoking status included 1077 (17.2%) current, 1694 (27.0%) former, and 3508 (55.9%) never. Median follow-up was 78.4 (IQR, 30.5-119.6) months. Current smoking was associated with male sex, younger age, trunk site, thicker tumors, tumor ulceration, and SLNB positivity. Current smoking was associated with a greater risk of melanoma-associated death by multivariable analysis for the entire study (hazard ratio [HR], 1.48 [95% CI, 1.26-1.75]; P < .001). Former smoking was not. The increased risk of melanoma-specific mortality associated with current smoking was greatest for patients with SLNB-negative melanoma (HR, 1.85 [95% CI, 1.35-2.52]; P < .001), but also present for patients with SLNB-positive melanoma (HR, 1.29 [95% CI, 1.04-1.59]; P = .02) and nodal observation (HR, 1.68 [95% CI, 1.09-2.61]; P = .02). Smoking at least 20 cigarettes/d doubled the risk of death due to melanoma for patients with SLNB-negative disease (HR, 2.06 [95% CI, 1.36-3.13]; P < .001). Conclusions and Relevance: The findings of this cohort study suggest that patients with clinical stage I and II melanoma who smoked had a significantly increased risk of death due to melanoma. Smoking status should be assessed at time of melanoma diagnosis and may be considered a risk factor for disease progression.
Subject(s)
Melanoma , Skin Neoplasms , Humans , Male , Female , Melanoma/epidemiology , Melanoma/surgery , Skin Neoplasms/epidemiology , Skin Neoplasms/surgery , Cohort Studies , Smoking/epidemiology , Tobacco SmokingABSTRACT
BACKGROUND: Minimally invasive inguinal lymphadenectomy (MILND) is safe and feasible, but limited data exist regarding oncologic outcomes. METHODS: This study performed a multi-institutional retrospective cohort analysis of consecutive MILND performed for melanoma between January 2009 and June 2016. The open ILND (OILND) comparative cohort comprised patients enrolled in the second Multicenter Selective Lymphadenectomy Trial (MSLT-II) between December 2004 and March 2014.The pre-defined primary end point was the same-basin regional nodal recurrence, calculated using properties of binomial distribution. Time to events was calculated using the Kaplan-Meier method. The secondary end points were overall survival, progression-free survival, melanoma-specific survival (MSS), and distant metastasis-free survival (DMFS). RESULTS: For all the patients undergoing MILND, the same-basin regional recurrence rate was 4.4 % (10/228; 95 % confidence interval [CI], 2.1-7.9 %): 8.2 % (4/49) for clinical nodal disease and 3.4 % (6/179) for patients with a positive sentinel lymph node (SLN) as the indication. For the 288 patients enrolled in MSLT-II who underwent OILND for a positive SLN, 17 (5.9 %) had regional node recurrence as their first event. After controlling for ulceration, positive LN count and positive non-SLNs at the time of lymphadenectomy, no difference in OS, PFS, MSS or DMFS was observed for patients with a positive SLN who underwent MILND versus OILND. CONCLUSION: This large multi-institutional experience supports the oncologic safety of MILND for melanoma. The outcomes in this large multi-institutional experience of MILND compared favorably with those for an OILND population during similar periods, supporting the oncologic safety of MILND for melanoma.
Subject(s)
Melanoma , Skin Neoplasms , Humans , Lymph Node Excision/methods , Melanoma/pathology , Retrospective Studies , Sentinel Lymph Node Biopsy/methods , Skin Neoplasms/pathologyABSTRACT
PURPOSE: As clinical management decisions in patients with Stage III melanoma have become more complex, precise pathologic characterization of sentinel lymph node (SLN) metastases has become critical to guide management. The extent of SLN involvement correlates with risk of adverse outcomes, but reported methods of disease quantification vary. We examined SLN metastases from patients participating in an international clinical trial and compared several methods of tumor burden quantification. METHODS: SLNs from 146 node-positive patients in the first Multicenter Selective Lymphadenectomy Trial (MSLT-I) were centrally-reviewed and characterized by number of tumor-positive nodes, percent nodal area tumor replacement, maximum dimension of largest metastasis, tumor penetrative depth, number of tumor foci, metastasis microanatomic location, and extracapsular extension. These data were analyzed for correlation with non-SLN metastasis and melanoma-specific survival (MSS). RESULTS: The median number of tumor-involved SLNs was 1. The median maximum metastasis dimension was 1.11 mm. Median SLN area involvement was 1.5%. Tumor burden measures were highly correlated with each other. Factors associated with non-SLN metastasis by univariable analysis were primary tumor ulceration and extent of metastases. Tumor thickness, ulceration, non-SLN metastasis and multiple measures of SLN tumor burden were significantly related to MSS on univariable analysis. After multivariable adjustment, number of involved SLNs (p = 0.05) and percent nodal area tumor replacement (p = 0.02) were independent predictors of MSS. CONCLUSION: Central review of MSLT-I pathology indicates that primary tumor and SLN tumor characteristics predict non-SLN metastasis and MSS. Percent nodal involvement was more powerfully prognostic than the more commonly used maximum dimension of largest metastasis.
Subject(s)
Lymphadenopathy , Melanoma , Sentinel Lymph Node , Skin Neoplasms , Humans , Lymph Node Excision , Lymph Nodes/pathology , Lymph Nodes/surgery , Lymphatic Metastasis/pathology , Melanoma/pathology , Prognosis , Sentinel Lymph Node/pathology , Sentinel Lymph Node Biopsy , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Tumor BurdenABSTRACT
Wound healing is a multi-step process to rapidly restore the barrier function. This process is often impaired in diabetic patients resulting in chronic wounds and amputation. We previously found that paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway via topical administration of the BRAF inhibitor vemurafenib accelerates wound healing by activating keratinocyte proliferation and reepithelialization pathways in healthy mice. Herein, we investigated whether this wound healing acceleration also occurs in impaired diabetic wounds and found that topical vemurafenib not only improves wound healing in a murine diabetic wound model but unexpectedly promotes hair follicle regeneration. Hair follicles expressing Sox-9 and K15 surrounded by CD34+ stroma were found in wounds of diabetic and non-diabetic mice, and their formation can be prevented by blocking downstream MEK signaling. Thus, topically applied BRAF inhibitors may accelerate wound healing, and promote the restoration of improved skin architecture in both normal and impaired wounds.
Subject(s)
Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Regeneration/drug effects , Wound Healing/drug effects , Administration, Topical , Animals , Diabetes Mellitus, Experimental/pathology , Female , Hair Follicle/physiology , Mice , Mice, Inbred BALB C , Mice, Obese , Proto-Oncogene Proteins B-raf/metabolism , Skin/pathology , Vemurafenib/pharmacology , Wnt Signaling Pathway/drug effects , beta Catenin/metabolismABSTRACT
OBJECTIVE: To assess whether preoperative ultrasound (US) assessment of regional lymph nodes in patients who present with primary cutaneous melanoma provides accurate staging. BACKGROUND: It has been suggested that preoperative US could avoid the need for sentinel node (SN) biopsy, but in most single-institution reports, the sensitivity of preoperative US has been low. METHODS: Preoperative US data and SNB results were analyzed for patients enrolled at 20 centers participating in the screening phase of the second Multicenter Selective Lymphadenectomy Trial. Excised SNs were histopathologically assessed and considered positive if any melanoma was seen. RESULTS: SNs were identified and removed from 2859 patients who had preoperative US evaluation. Among those patients, 548 had SN metastases. US was positive (abnormal) in 87 patients (3.0%). Among SN-positive patients, 39 (7.1%) had an abnormal US. When analyzed by lymph node basin, 3302 basins were evaluated, and 38 were true positive (1.2%). By basin, the sensitivity of US was 6.6% (95% confidence interval: 4.6-8.7) and the specificity 98.0% (95% CI: 97.5-98.5). Median cross-sectional area of all SN metastases was 0.13âmm2; in US true-positive nodes, it was 6.8âmm2. US sensitivity increased with increasing Breslow thickness of the primary melanoma (0% for ≤1âmm thickness, 11.9% for >4âmm thickness). US sensitivity was not significantly greater with higher trial center volume or with pre-US lymphoscintigraphy. CONCLUSION: In the MSLT-II screening phase population, SN tumor volume was usually too small to be reliably detected by US. For accurate nodal staging to guide the management of melanoma patients, US is not an effective substitute for SN biopsy.
Subject(s)
Lymph Node Excision , Lymph Nodes/diagnostic imaging , Melanoma/diagnosis , Neoplasm Staging/methods , Preoperative Care/methods , Skin Neoplasms/diagnosis , Ultrasonography/methods , Follow-Up Studies , Humans , Lymphatic Metastasis , Melanoma/secondary , Melanoma/surgery , Retrospective Studies , Skin Neoplasms/surgeryABSTRACT
BACKGROUND: Recommended treatment for patients with sentinel lymph node (SLN)-positive melanoma has recently changed. Randomized trials demonstrated equivalent survival with close observation versus completion lymph node dissection (CLND), but increased regional node recurrence. We evaluated factors related to in-basin nodal recurrence after lymphadenectomy (LND) for SLN-positive or macroscopic nodal metastases. METHODS: An institutional database and the first Multicenter Selective Lymphadenectomy Trial (MSLT-I) were analyzed independently. Exclusions were multiple primaries, multi-basin involvement, or in-transit metastases. Patient demographics, primary tumor thickness and ulceration, lymph nodes retrieved, and use of adjuvant radiotherapy were analyzed. Multivariate analyses were performed to determine factors predicting in-basin nodal recurrence (significance p ≤ 0.05). RESULTS: The retrospective cohort (577 patients) showed an in-basin failure rate of 6.6% after CLND for a positive SLN and 13.1% after LND for palpable disease (p = 0.001). This recurrence risk persisted after adjustment for patient, tumor, and LND factors [hazard ratio (HR) 2.32; p = 0.004]. In the MSLT-I cohort (326 patients), the failure rate after CLND following SLNB was 6.2%, but 10.1% after LND for palpable recurrence in observation patients. After adjustment for other factors, macroscopic disease was associated with an increased risk of recurrence after LND (HR 2.24; p = 0.05). CONCLUSION: After LND for melanoma, in-basin recurrence is infrequent, but a clinically significant fraction will fail. Failure is less likely if dissection is performed for clinically occult disease. Further research is warranted to evaluate the long-term regional control and quality of life associated with nodal basin observation, which has now become standard practice.
Subject(s)
Lymph Node Excision/mortality , Melanoma/pathology , Melanoma/therapy , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/therapy , Sentinel Lymph Node Biopsy , Databases, Factual , Female , Humans , Male , Melanoma/mortality , Middle Aged , Multivariate Analysis , Neoplasm Recurrence, Local/mortality , Neoplasm Staging , Quality of Life , Radiotherapy, Adjuvant , Retrospective Studies , Survival RateABSTRACT
PURPOSE: Transgenic adoptive cell therapy (ACT) targeting the tumor antigen NY-ESO-1 can be effective for the treatment of sarcoma and melanoma. Preclinical models have shown that this therapy can be improved with the addition of dendritic cell (DC) vaccination and immune checkpoint blockade. We studied the safety, feasibility, and antitumor efficacy of transgenic ACT with DC vaccination, with and without CTLA-4 blockade with ipilimumab. PATIENTS AND METHODS: Freshly prepared autologous NY-ESO-1-specific T-cell receptor (TCR) transgenic lymphocytes were adoptively transferred together with NY-ESO-1 peptide-pulsed DC vaccination in HLA-A2.1-positive subjects alone (ESO, NCT02070406) or with ipilimumab (INY, NCT01697527) in patients with advanced sarcoma or melanoma. RESULTS: Six patients were enrolled in the ESO cohort, and four were enrolled in the INY cohort. Four out of six patients treated per ESO (66%), and two out of four patients treated per INY (50%) displayed evidence of tumor regression. Peripheral blood reconstitution with NY-ESO-1-specific T cells peaked within 2 weeks of ACT, indicating rapid in vivo expansion. Tracking of transgenic T cells to the tumor sites was demonstrated in on-treatment biopsies via TCR sequencing. Multiparametric mass cytometry of transgenic cells demonstrated shifting of transgenic cells from memory phenotypes to more terminally differentiated effector phenotypes over time. CONCLUSIONS: ACT of fresh NY-ESO-1 transgenic T cells prepared via a short ex vivo protocol and given with DC vaccination, with or without ipilimumab, is feasible and results in transient antitumor activity, with no apparent clinical benefit of the addition of ipilimumab. Improvements are needed to maintain tumor responses.
Subject(s)
Adoptive Transfer , Antineoplastic Agents, Immunological/pharmacology , Cancer Vaccines/immunology , Dendritic Cells/immunology , Ipilimumab/pharmacology , Neoplasms/immunology , Neoplasms/therapy , Adoptive Transfer/methods , Adult , Animals , CTLA-4 Antigen/antagonists & inhibitors , Cell Line, Tumor , Combined Modality Therapy , Dendritic Cells/metabolism , Female , Gene Knock-In Techniques , Humans , Immunotherapy , Lymphocytes/immunology , Lymphocytes/metabolism , Male , Mice , Middle Aged , Molecular Targeted Therapy , Neoplasms/pathology , Phenotype , Pilot Projects , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism , Young AdultABSTRACT
A promising arsenal of targeted and immunotherapy treatments for metastatic melanoma has emerged over the last decade. With these therapies, we now face new mechanisms of tumor-acquired resistance. We report here a patient whose metastatic melanoma underwent dedifferentiation as a resistance mechanism to adoptive T-cell transfer therapy (ACT) to the MART1 antigen, a phenomenon that had been observed only in mouse studies to date. After an initial period of tumor regression, the patient presented in relapse with tumors lacking melanocytic antigens (MART1, gp100) and expressing an inflammation-induced neural crest marker (NGFR). We demonstrate using human melanoma cell lines that this resistance phenotype can be induced in vitro by treatment with MART1 T cell receptor-expressing T cells or with TNFα, and that the phenotype is reversible with withdrawal of inflammatory stimuli. This supports the hypothesis that acquired resistance to cancer immunotherapy can be mediated by inflammation-induced cancer dedifferentiation.Significance: We report a patient whose metastatic melanoma underwent inflammation-induced dedifferentiation as a resistance mechanism to ACT to the MART1 antigen. Our results suggest that future melanoma ACT protocols may benefit from the simultaneous targeting of multiple tumor antigens, modulating the inflammatory response, and inhibition of inflammatory dedifferentiation-inducing signals. Cancer Discov; 8(8); 935-43. ©2018 AACR.This article is highlighted in the In This Issue feature, p. 899.
Subject(s)
Drug Resistance, Neoplasm , MART-1 Antigen/immunology , Melanoma/therapy , Nerve Tissue Proteins/metabolism , Nevus, Pigmented/therapy , Receptors, Nerve Growth Factor/metabolism , Cell Dedifferentiation , Cell Line, Tumor , Coculture Techniques , Humans , Immunotherapy, Adoptive , Male , Melanoma/immunology , Middle Aged , Neoplasm Metastasis , Nevus, Pigmented/immunology , Receptors, Chimeric Antigen/metabolism , RecurrenceABSTRACT
Desmoplastic melanoma is a rare subtype of melanoma characterized by dense fibrous stroma, resistance to chemotherapy and a lack of actionable driver mutations, and is highly associated with ultraviolet light-induced DNA damage. We analysed sixty patients with advanced desmoplastic melanoma who had been treated with antibodies to block programmed cell death 1 (PD-1) or PD-1 ligand (PD-L1). Objective tumour responses were observed in forty-two of the sixty patients (70%; 95% confidence interval 57-81%), including nineteen patients (32%) with a complete response. Whole-exome sequencing revealed a high mutational load and frequent NF1 mutations (fourteen out of seventeen cases) in these tumours. Immunohistochemistry analysis from nineteen desmoplastic melanomas and thirteen non-desmoplastic melanomas revealed a higher percentage of PD-L1-positive cells in the tumour parenchyma in desmoplastic melanomas (P = 0.04); these cells were highly associated with increased CD8 density and PD-L1 expression in the tumour invasive margin. Therefore, patients with advanced desmoplastic melanoma derive substantial clinical benefit from PD-1 or PD-L1 immune checkpoint blockade therapy, even though desmoplastic melanoma is defined by its dense desmoplastic fibrous stroma. The benefit is likely to result from the high mutational burden and a frequent pre-existing adaptive immune response limited by PD-L1 expression.
Subject(s)
Immunotherapy , Melanoma/immunology , Melanoma/therapy , Programmed Cell Death 1 Receptor/antagonists & inhibitors , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/metabolism , Biopsy , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/immunology , Cell Cycle Checkpoints , Humans , Melanoma/genetics , Melanoma/metabolism , Mutation/genetics , Neurofibromin 1/genetics , Programmed Cell Death 1 Receptor/metabolism , Retrospective StudiesSubject(s)
Melanoma , Sentinel Lymph Node Biopsy , Humans , Lymph Nodes , Lymphatic Metastasis , Skin NeoplasmsABSTRACT
BACKGROUND: Hypothetically, delay between melanoma diagnosis and SLNB could affect outcomes, either adversely by allowing growth and dissemination of metastases, or beneficially by allowing development of an anti-melanoma immune response. Available data are conflicting about the effect of SLNB delay on patient survival. Our objective was to determine whether delay between initial diagnosis and SLNB affects outcomes in patients with cutaneous melanoma. STUDY DESIGN: We performed query and analysis of a large prospectively maintained database of patients with primary cutaneous melanomas undergoing SLNB. An independent dataset from MSLT-1 (Multicenter Selective Lymphadenectomy Trial-1) was used for validation. Primary outcomes included disease-free survival and melanoma-specific survival. RESULTS: Early and delayed SLNB were defined as less than 30 and 30 or more days from initial diagnosis, respectively. There were 2,483 patients that met inclusion criteria. Positive sentinel lymph nodes were identified in 17.4% (n = 432). Among all patients, 42% had SLNB 30 or more days after diagnosis and 37% of positive sentinel lymph nodes were at 30 or more days. No differences in sex, anatomic site, or histopathologic features were identified between the 2 groups. There was no difference in melanoma-specific survival or disease-free survival between those undergoing early or delayed SLNB. Examination of MSLT-1 trial data similarly demonstrated no difference in survival outcomes. CONCLUSIONS: This, the largest study on this subject to date, found no adverse impact on long-term clinical outcomes of patients due to delay of SLNB beyond 30 days. The MSLT-1 data confirm this result. Patients can be reassured that if the operation is performed 30 or more days after diagnosis, it will not cause harm.
Subject(s)
Melanoma/pathology , Melanoma/surgery , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Delayed Diagnosis , Disease-Free Survival , Female , Humans , Male , Melanoma/mortality , Middle Aged , Retrospective Studies , Sentinel Lymph Node Biopsy , Skin Neoplasms/mortality , Survival Rate , Treatment Outcome , Young AdultABSTRACT
BACKGROUND: Sentinel-lymph-node biopsy is associated with increased melanoma-specific survival (i.e., survival until death from melanoma) among patients with node-positive intermediate-thickness melanomas (1.2 to 3.5 mm). The value of completion lymph-node dissection for patients with sentinel-node metastases is not clear. METHODS: In an international trial, we randomly assigned patients with sentinel-node metastases detected by means of standard pathological assessment or a multimarker molecular assay to immediate completion lymph-node dissection (dissection group) or nodal observation with ultrasonography (observation group). The primary end point was melanoma-specific survival. Secondary end points included disease-free survival and the cumulative rate of nonsentinel-node metastasis. RESULTS: Immediate completion lymph-node dissection was not associated with increased melanoma-specific survival among 1934 patients with data that could be evaluated in an intention-to-treat analysis or among 1755 patients in the per-protocol analysis. In the per-protocol analysis, the mean (±SE) 3-year rate of melanoma-specific survival was similar in the dissection group and the observation group (86±1.3% and 86±1.2%, respectively; P=0.42 by the log-rank test) at a median follow-up of 43 months. The rate of disease-free survival was slightly higher in the dissection group than in the observation group (68±1.7% and 63±1.7%, respectively; P=0.05 by the log-rank test) at 3 years, based on an increased rate of disease control in the regional nodes at 3 years (92±1.0% vs. 77±1.5%; P<0.001 by the log-rank test); these results must be interpreted with caution. Nonsentinel-node metastases, identified in 11.5% of the patients in the dissection group, were a strong, independent prognostic factor for recurrence (hazard ratio, 1.78; P=0.005). Lymphedema was observed in 24.1% of the patients in the dissection group and in 6.3% of those in the observation group. CONCLUSIONS: Immediate completion lymph-node dissection increased the rate of regional disease control and provided prognostic information but did not increase melanoma-specific survival among patients with melanoma and sentinel-node metastases. (Funded by the National Cancer Institute and others; MSLT-II ClinicalTrials.gov number, NCT00297895 .).
Subject(s)
Lymph Node Excision , Melanoma/secondary , Sentinel Lymph Node Biopsy , Sentinel Lymph Node/surgery , Watchful Waiting , Adult , Aged , Disease-Free Survival , Female , Humans , Intention to Treat Analysis , Lymph Node Excision/adverse effects , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Lymphatic Metastasis/diagnosis , Lymphedema/etiology , Male , Melanoma/mortality , Melanoma/pathology , Melanoma/surgery , Middle Aged , Neoplasm Staging/methods , Postoperative Complications , Prognosis , Proportional Hazards Models , Sentinel Lymph Node/pathology , Sentinel Lymph Node Biopsy/adverse effects , Survival Analysis , Ultrasonography , Young AdultABSTRACT
BRAF inhibitors are highly effective therapies for the treatment of BRAF(V600)-mutated melanoma, with the main toxicity being a variety of hyperproliferative skin conditions due to paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in BRAF wild-type cells. Most of these hyperproliferative skin changes improve when a MEK inhibitor is co-administered, as it blocks paradoxical MAPK activation. Here we show how the BRAF inhibitor vemurafenib accelerates skin wound healing by inducing the proliferation and migration of human keratinocytes through extracellular signal-regulated kinase (ERK) phosphorylation and cell cycle progression. Topical treatment with vemurafenib in two wound-healing mice models accelerates cutaneous wound healing through paradoxical MAPK activation; addition of a mitogen-activated protein kinase kinase (MEK) inhibitor reverses the benefit of vemurafenib-accelerated wound healing. The same dosing regimen of topical BRAF inhibitor does not increase the incidence of cutaneous squamous cell carcinomas in mice. Therefore, topical BRAF inhibitors may have clinical applications in accelerating the healing of skin wounds.
Subject(s)
MAP Kinase Signaling System/drug effects , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Skin/drug effects , Wound Healing/drug effects , Administration, Topical , Animals , Carcinogenesis/drug effects , Carcinogenesis/pathology , Carcinogens/toxicity , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/pathology , Cell Cycle/drug effects , Cell Line, Tumor , Female , Humans , Incidence , Indoles/pharmacology , Indoles/therapeutic use , Keratinocytes , Mice , Mice, Inbred BALB C , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , Neoplasms, Experimental/chemically induced , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/epidemiology , Neoplasms, Experimental/pathology , Protein Kinase Inhibitors/therapeutic use , Pyridones/pharmacology , Pyridones/therapeutic use , Pyrimidinones/pharmacology , Pyrimidinones/therapeutic use , Skin/metabolism , Skin/pathology , Skin Neoplasms/chemically induced , Skin Neoplasms/drug therapy , Skin Neoplasms/epidemiology , Skin Neoplasms/pathology , Sulfonamides/pharmacology , Sulfonamides/therapeutic use , Treatment Outcome , VemurafenibABSTRACT
Keratoacanthoma is a controversial entity. Some consider keratoacanthoma as a variant of squamous cell carcinoma, whereas others see it as a distinct self-resolving squamoproliferative lesion. Our objective is to examine the relationship of keratoacanthoma with squamous cell carcinoma and normal skin by using DNA microarrays. DNA microarray studies were performed on formalin-fixed and paraffin-embedded blocks from ten cases of actinic keratoacanthoma utilizing the U133plus2.0 array. These results were compared with our previously developed microarray database of ten squamous cell carcinoma and ten normal skin samples. Keratoacanthoma demonstrated 1449 differentially expressed genes in comparison with squamous cell carcinoma (>5-fold change: P<0.01) with 908 genes upregulated and 541 genes downregulated. Keratoacanthoma showed 2435 differentially expressed genes in comparison with normal skin (>5-fold change: P<0.01) with 1085 genes upregulated and 1350 genes downregulated. The most upregulated genes, comparing keratoacanthoma with normal skin included MALAT1, S100A8, CDR1, TPM4, and CALM1. The most downregulated genes included SCGB2A2, DCD, THRSP, ADIPOQ, adiponectin, and ADH1B. The molecular biological pathway analysis comparing keratoacanthoma with normal skin showed that cellular development, cellular growth and proliferation, cell death/apoptosis, and cell cycle pathways are prominently involved in the pathogenesis of keratoacanthoma. The most enriched canonical pathways were clathrin-mediated endocytosis signaling, molecular mechanisms of cancer and integrin signaling. The distinctive gene expression profile of keratoacanthoma reveals that it is molecularly distinct from squamous cell carcinoma. The molecular pathways and genes differentially expressed in comparing keratoacanthoma with normal skin suggest that keratoacanthoma is a neoplasm that can regress due to upregulation of the cell death/apoptosis pathway.