Differential proteomic expression profiles in vulvar lichen planus as compared to normal vulvar tissue, vulvar lichen sclerosus, or oral lichen planus: An exploratory study.

Vulvar lichen planus (VLP) is a chronic inflammatory disease which adversely affects patients' quality of life. The pathogenesis of VLP is unknown although Th1 immune response has been implicated. We aimed to discover specific tissue-based protein biomarkers in VLP compared to normal vulvar tissue (NVT), vulvar lichen sclerosus (VLS) and oral lichen planus (OLP). We used laser capture microdissection-liquid chromatography- tandem mass spectrometry to assess protein expression in fixed lesional mucosal specimens from patients with VLP (n = 5). We then compared proteomic profiles against those of NVT (n = 4), VLS (n = 5), OLP (n = 6) and normal oral mucosa (n = 5), previously published by our group. IL16, PTPRC, PTPRCAP, TAP1 and ITGB2 and were significantly overexpressed in VLP compared to NVT. Ingenuity pathway analysis identified antigen presentation and integrin signalling pathways. Proteins overexpressed in both VLP versus NVT and OLP versus NOM included IL16, PTPRC, PTPRCAP, TAP1, HLA-DPB1, HLA-B and HLA-DRA. This proteomic analysis revealed several overexpressed proteins in VLP that relate to Th1 autoimmunity, including IL16. Overlapping pathways, including those involving IFNγ and Th1 signalling, were observed between VLP, VLS, and OLP.

Differential proteomic expression in indolent versus transforming oral lichen planus.

Oral lichen planus (OLP) confers an approximately 1% risk of transformation to oral squamous cell carcinoma (OSCC). Early identification of high-risk OLP would be very helpful for optimal patient management. We aimed to discover specific tissue-based protein biomarkers in patients with OLP who developed OSCC compared to those who did not. We used laser capture microdissection- and nanoLC-tandem mass spectrometry to assess protein expression in fixed lesional mucosal specimens in patients with indolent OLP (no OSCC after at least 5-year follow-up, n = 6), transforming OLP (non-dysplastic epithelium with lichenoid inflammation marginal to OSCC, n = 6) or normal oral mucosa (NOM, n = 5). Transforming OLP protein profile was enriched for actin cytoskeleton, mitochondrial dysfunction and oxidative phosphorylation pathways. CA1, TNNT3, SYNM and MB were overexpressed, and FBLN1 was underexpressed in transforming OLP compared with indolent OLP. Integrin signalling and antigen presentation pathways were enriched in both indolent and transforming OLP compared with NOM. This proteomic study provides potential biomarkers, such as CA1 overexpression, for higher-risk OLP. While further validation studies are needed, we propose that epithelial-mesenchymal transition may be involved in OLP carcinogenesis.

Differential proteomic expression in indolent vulvar lichen sclerosus, transforming vulvar lichen sclerosus and normal vulvar tissue.

Vulvar lichen sclerosus (VLS) confers approximately 3% risk of malignant transformation to vulvar squamous cell carcinoma (VSCC). We used unbiased proteomic methods to identify differentially expressed proteins in tissue of patients with VLS who developed VSCC compared to those who did not. We used laser capture microdissection- and nanoLC-tandem mass spectrometry to assess protein expression in individuals in normal vulvar tissue (NVT, n = 4), indolent VLS (no VSCC after at least 5 years follow-up, n = 5) or transforming VSCC (preceding VSCC, n = 5). Interferon-γ and antigen-presenting pathways are overexpressed in indolent and transforming VLS compared to NVT. There was differential expression of malignancy-related proteins in transforming VLS compared to indolent VLS (CAV1 overexpression, AKAP12 underexpression), particularly in the EIF2 translation pathway, which has been previously implicated in carcinogenesis. Results of this study provide additional molecular evidence supporting the concept that VLS is a risk factor for VSCC and highlights possible future biomarkers and/or therapeutic targets.

Whole-exome sequencing of transforming oral lichen planus reveals mutations in DNA damage repair and apoptosis pathway genes.

BACKGROUND: Oral lichen planus confers a 1% risk of transformation to oral squamous cell carcinoma. While prior exome sequencing studies have identified multiple genetic mutations in oral squamous cell carcinoma, mutational analyses of lichen planus-derived OSCC are lacking. We sought to clarify genomic events associated with oral lichen planus transformation. METHODS: Using rigorous diagnostic criteria, we retrospectively identified patients with non-transforming oral lichen planus (i.e., known to be non-transforming with 5 years of clinical follow-up; n = 17), transforming oral lichen planus (tissue marginal to oral squamous cell carcinoma, n = 9), or oral squamous cell carcinoma arising in lichen planus (n = 17). Gene mutational profiles derived from whole-exome sequencing on fixed mucosal specimens were compared among the groups. RESULTS: The four most frequently mutated genes in transforming oral lichen planus and oral squamous cell carcinoma (TP53, CELSR1, CASP8, and KMT2D) identified 12/17 (71%) of oral squamous cell carcinomas and 5/9 (56%) of transforming oral lichen planus but were absent in non-transforming oral lichen planus. We identified other known oral squamous cell carcinoma mutations (TRRAP, OBSCN, and LRP2) but also previously unreported mutations (TENM3 and ASH1L) in lichen planus-associated oral squamous cell carcinomas. CONCLUSIONS: These findings suggest alterations in DNA damage response and apoptosis pathways underlie lichen planus-related oral squamous cell carcinoma transformation and are supported by mutational signatures indicative of DNA damage. This study characterized patterns of mutational events present in oral lichen planus associated with squamous cell carcinoma and in squamous cell carcinoma associated with oral lichen planus but not in non-transforming oral lichen planus.

Cutaneous sarcoid-like drug reaction caused by an anaplastic lymphoma kinase inhibitor.

Anaplastic lymphoma kinase (ALK) rearranged lung cancers represent 4% to 6% of all pulmonary adenocarcinomas, and echinoderm microtubule associated protein like 4 (EML4)-ALK fusions are the most common subgroup. Herein, we report a case of two successive drug reactions due to ALK inhibitors. A 69-year-old female with stage IVB EML4-ALK fused lung adenocarcinoma developed a generalized morbilliform eruption 10 days after starting alectinib. Skin biopsy findings were consistent with a drug reaction. Her findings resolved after alectinib was discontinued. Another ALK inhibitor, lorlatinib was started and she developed multiple asymptomatic cutaneous and oral nodules 4 months later. Biopsies from these nodules showed sarcoidal granulomas without evidence of metastases or infection. ALK inhibitors are associated with numerous adverse events, including various cutaneous eruptions. However, a sarcoidal drug reaction involving the skin has not been reported. Identification of drug reactions to targeted therapy can avoid long-term sequelae and misinterpretation of the clinical findings as disease progression or infection.