ABSTRACT
Among skin epithelial tumors, recurrent mutations in the APC/CTNNB1 genes resulting in activation of the Wnt/ß-catenin pathway have been reported predominantly in neoplasms with matrical differentiation. In the present study, we describe the morphologic, immunohistochemical, and genetic features of 16 primary cutaneous carcinomas harboring mutations activating the Wnt/ß-catenin pathway without evidence of matrical differentiation, as well as four combined tumors in which a similar Wnt/ß-catenin activated carcinoma component was associated with Merkel cell carcinoma or pilomatrical carcinoma. Among the pure tumor cases, 6/16 patients were female with a median age of 80 years (range: 58-98). Tumors were located on the head and neck (n=7, 44%), upper limb (n=4, 25%), trunk (n=3, 18%), and leg (n=2, 13%). Metastatic spread was observed in 4 cases resulting in death from disease in one patient. Microscopically, all cases were poorly differentiated neoplasms infiltrating the dermis and/or subcutaneous tissue. In 13 cases, solid "squamoid" areas were associated with a basophilic component characterized by rosette/pseudoglandular formation resulting in a biphasic appearance. Three specimens consisted only of poorly differentiated carcinoma lacking rosette formation. Immunohistochemical studies showed frequent expression of EMA (100%), BerEP4 (100%), cytokeratin 7 (94%), chromogranin A (44%), synaptophysin (82%) and cytokeratin 20 (69%). Complete loss of Rb expression was observed in all but one case. Nuclear ß-catenin and CDX2 expressions were detected in all cases. Recurrent pathogenic somatic mutations were observed in APC (60%), CTNNB1 (40%) and RB1 (n=47%). Global methylation analysis confirmed that cases with rosette formation constituted a homogenous tumor group distinct from established skin tumor entities (pilomatrical carcinoma, Merkel cell carcinoma and squamous cell carcinoma) while the 3 other cases lacking such morphologic features did not. In addition, we identified four combined neoplasms in which there was a component showing a similar poorly differentiated rosette forming carcinoma demonstrating Rb loss and beta-catenin activation associated with either Merkel cell carcinoma (n=3) or pilomatrical carcinoma (n=1). In conclusion, we describe a distinctive neoplasm, for which we propose the term "Wnt/ß-catenin activated rosette-forming carcinoma", morphologically characterized by the association of rosette formation, squamous and/or neuroendocrine differentiation, diffuse CDX2 expression, Rb loss, and mutations in CTNNB1/APC genes.
ABSTRACT
Merkel cell carcinoma (MCC) is an aggressive skin cancer frequently caused by genomic integration of the Merkel cell polyomavirus (MCPyV). MCPyV-negative cases often present as combined MCCs, which represent a distinctive subset of tumors characterized by association of an MCC with a second tumor component, mostly squamous cell carcinoma. Up to now, only exceptional cases of combined MCC with neuroblastic differentiation have been reported. Herein we describe two additional combined MCCs with neuroblastic differentiation and provide comprehensive morphologic, immunohistochemical, transcriptomic, genetic and epigenetic characterization of these tumors, which both arose in elderly men and appeared as an isolated inguinal adenopathy. Microscopic examination revealed biphasic tumors combining a poorly differentiated high-grade carcinoma with a poorly differentiated neuroblastic component lacking signs of proliferation. Immunohistochemical investigation revealed keratin 20 and MCPyV T antigen (TA) in the MCC parts, while neuroblastic differentiation was confirmed in the other component in both cases. A clonal relation of the two components can be deduced from 20 and 14 shared acquired point mutations detected by whole exome analysis in both combined tumors, respectively. Spatial transcriptomics demonstrated a lower expression of stem cell marker genes such as SOX2 and MCM2 in the neuroblastic component. Interestingly, although the neuroblastic part lacked TA expression, the same genomic MCPyV integration and the same large T-truncating mutations were observed in both tumor parts. Given that neuronal transdifferentiation upon TA repression has been reported for MCC cell lines, the most likely scenario for the two combined MCC/neuroblastic tumors is that neuroblastic transdifferentiation resulted from loss of TA expression in a subset of MCC cells. Indeed, DNA methylation profiling suggests an MCC-typical cellular origin for the combined MCC/neuroblastomas. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Subject(s)
Antigens, Viral, Tumor , Carcinoma, Merkel Cell , Cell Transdifferentiation , Merkel cell polyomavirus , Skin Neoplasms , Humans , Carcinoma, Merkel Cell/pathology , Carcinoma, Merkel Cell/virology , Carcinoma, Merkel Cell/genetics , Carcinoma, Merkel Cell/metabolism , Male , Skin Neoplasms/pathology , Skin Neoplasms/genetics , Skin Neoplasms/virology , Skin Neoplasms/metabolism , Antigens, Viral, Tumor/genetics , Antigens, Viral, Tumor/metabolism , Merkel cell polyomavirus/genetics , Cell Cycle Checkpoints/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Aged, 80 and over , Aged , Neoplasms, Complex and Mixed/pathology , Neoplasms, Complex and Mixed/genetics , Neoplasms, Complex and Mixed/metabolism , Neuroblastoma/pathology , Neuroblastoma/genetics , Neuroblastoma/metabolismSubject(s)
Thyroid Neoplasms , Thyroid Nodule , Humans , Thyroid Neoplasms/diagnosis , World Health OrganizationABSTRACT
AIMS: Merkel cell carcinoma (MCC) is frequently caused by the Merkel cell polyomavirus (MCPyV). Characteristic for these virus-positive (VP) MCC is MCPyV integration into the host genome and truncation of the viral oncogene Large T antigen (LT), with full-length LT expression considered as incompatible with MCC growth. Genetic analysis of a VP-MCC/trichoblastoma combined tumour demonstrated that virus-driven MCC can arise from an epithelial cell. Here we describe two further cases of VP-MCC combined with an adnexal tumour, i.e. one trichoblastoma and one poroma. METHODS AND RESULTS: Whole-genome sequencing of MCC/trichoblastoma again provided evidence of a trichoblastoma-derived MCC. Although an MCC-typical LT-truncating mutation was detected, we could not determine an integration site and we additionally detected a wildtype sequence encoding full-length LT. Similarly, Sanger sequencing of the combined MCC/poroma revealed coding sequences for both truncated and full-length LT. Moreover, in situ RNA hybridization demonstrated expression of a late region mRNA encoding the viral capsid protein VP1 in both combined as well as in a few cases of pure MCC. CONCLUSION: The data presented here suggest the presence of wildtype MCPyV genomes and VP1 transcription in a subset of MCC.
Subject(s)
Carcinoma, Merkel Cell , Merkel cell polyomavirus , Polyomavirus Infections , Poroma , Skin Neoplasms , Sweat Gland Neoplasms , Humans , Carcinoma, Merkel Cell/metabolism , Merkel cell polyomavirus/genetics , Polyomavirus Infections/complications , Skin Neoplasms/pathology , GenomicsABSTRACT
Merkel cell carcinoma (MCC) is an aggressive skin cancer for which Merkel cell polyomavirus integration and expression of viral oncogenes small T and Large T have been identified as major oncogenic determinants. Recently, a component of the PRC2 complex, the histone methyltransferase enhancer of zeste homolog 2 (EZH2) that induces H3K27 trimethylation as a repressive mark has been proposed as a potential therapeutic target in MCC. Because divergent results have been reported for the levels of EZH2 and trimethylation of lysine 27 on histone 3, we analyzed these factors in a large MCC cohort to identify the molecular determinants of EZH2 activity in MCC and to establish MCC cell lines' sensitivity to EZH2 inhibitors. Immunohistochemical expression of EZH2 was observed in 92% of MCC tumors (156 of 170), with higher expression levels in virus-positive than virus-negative tumors (P = 0.026). For the latter, we showed overexpression of EZHIP, a negative regulator of the PRC2 complex. In vitro, ectopic expression of the large T antigen in fibroblasts led to the induction of EZH2 expression, whereas the knockdown of T antigens in MCC cell lines resulted in decreased EZH2 expression. EZH2 inhibition led to selective cytotoxicity on virus-positive MCC cell lines. This study highlights the distinct mechanisms of EZH2 induction between virus-negative and -positive MCC.
Subject(s)
Carcinoma, Merkel Cell , Merkel cell polyomavirus , Skin Neoplasms , Humans , Carcinoma, Merkel Cell/pathology , Histones/metabolism , Enhancer of Zeste Homolog 2 Protein/genetics , Enhancer of Zeste Homolog 2 Protein/metabolism , Skin Neoplasms/pathology , Merkel cell polyomavirus/genetics , Antigens, Viral, Tumor/genetics , Antigens, Viral, Tumor/metabolismABSTRACT
AIMS: Recently, YAP1 fusion genes have been demonstrated in eccrine poroma and porocarcinoma, and the diagnostic use of YAP1 immunohistochemistry has been highlighted in this setting. In other organs, loss of YAP1 expression can reflect YAP1 rearrangement or transcriptional repression, notably through RB1 inactivation. In this context, our objective was to re-evaluate the performance of YAP1 immunohistochemistry for the diagnosis of poroma and porocarcinoma. METHODS AND RESULTS: The expression of the C-terminal part of the YAP1 protein was evaluated by immunohistochemistry in 543 cutaneous epithelial tumours, including 27 poromas, 14 porocarcinomas and 502 other cutaneous tumours. Tumours that showed a lack of expression of YAP1 were further investigated for Rb by immunohistochemistry and for fusion transcripts by real-time PCR (YAP1::MAML2 and YAP1::NUTM1). The absence of YAP1 expression was observed in 24 cases of poroma (89%), 10 porocarcinoma (72%), 162 Merkel cell carcinoma (98%), 14 squamous cell carcinoma (SCC) (15%), one trichoblastoma and one sebaceoma. Fusions of YAP1 were detected in only 16 cases of poroma (n = 66%), 10 porocarcinoma (71%) all lacking YAP1 expression, and in one sebaceoma. The loss of Rb expression was detected in all cases except one of YAP1-deficient SCC (n = 14), such tumours showing significant morphological overlap with porocarcinoma. In-vitro experiments in HaCat cells showed that RB1 knockdown resulted in repression of YAP1 protein expression. CONCLUSION: In addition to gene fusion, we report that transcriptional repression of YAP1 can be observed in skin tumours with RB1 inactivation, including MCC and a subset of SCC.
Subject(s)
Carcinoma , Eccrine Porocarcinoma , Poroma , Skin Neoplasms , Sweat Gland Neoplasms , Humans , Poroma/genetics , Poroma/metabolism , Poroma/pathology , Sweat Gland Neoplasms/diagnosis , Eccrine Porocarcinoma/genetics , Eccrine Porocarcinoma/pathology , Skin Neoplasms/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Ubiquitin-Protein Ligases/metabolism , Retinoblastoma Binding Proteins/metabolismABSTRACT
MCC (Merkel cell carcinoma) is an aggressive neuroendocrine cutaneous neoplasm. Integration of the Merkel cell polyomavirus (MCPyV) is observed in about 80% of the cases, while the remaining 20% are related to UV exposure. Both MCPyV-positive and -negative MCCs-albeit by different mechanisms-are associated with RB1 inactivation leading to overexpression of SOX2, a major contributor to MCC biology. Moreover, although controversial, loss of RB1 expression seems to be restricted to MCPyV-negative cases.The aim of the present study was to assess the performances of RB1 loss and SOX2 expression detected by immunohistochemistry to determine MCPyV status and to diagnose MCC, respectively.Overall, 196 MCC tumors, 233 non-neuroendocrine skin neoplasms and 70 extra-cutaneous neuroendocrine carcinomas (NEC) were included. SOX2 and RB1 expressions were assessed by immunohistochemistry in a tissue micro-array. Diagnostic performances were determined using the likelihood ratio (LHR).RB1 expression loss was evidenced in 27% of the MCC cases, 12% of non-neuroendocrine skin tumors and 63% of extra-cutaneous NEC. Importantly, among MCC cases, RB1 loss was detected in all MCPyV(-) MCCs, while MCPyV( +) cases were consistently RB1-positive (p < 0.001). SOX2 diffuse expression was observed in 92% of the MCC cases and almost never observed in non-neuroendocrine skin epithelial neoplasms (2%, p < 0.0001, LHR + = 59). Furthermore, SOX2 diffuse staining was more frequently observed in MCCs than in extra-cutaneous NECs (30%, p < 0.001, LHR + = 3.1).These results confirm RB1 as a robust predictor of MCC viral status and further suggest SOX2 to be a relevant diagnostic marker of MCC.
Subject(s)
Carcinoma, Merkel Cell , Merkel cell polyomavirus , Polyomavirus Infections , Skin Neoplasms , Tumor Virus Infections , Carcinoma, Merkel Cell/diagnosis , Carcinoma, Merkel Cell/pathology , Humans , Merkel cell polyomavirus/metabolism , Polyomavirus Infections/complications , Polyomavirus Infections/metabolism , Retinoblastoma Binding Proteins , SOXB1 Transcription Factors/metabolism , Skin Neoplasms/pathology , Tumor Virus Infections/complications , Ubiquitin-Protein LigasesABSTRACT
Antibody-drug conjugates (ADCs) are an emerging class of therapeutics, with twelve FDA- and EMA-approved drugs for hematological and solid cancers. Such drugs consist in a monoclonal antibody linked to a cytotoxic agent, allowing a specific cytotoxicity to tumor cells. In recent years, tremendous progress has been observed in therapeutic approaches for advanced skin cancer patients. In this regard, targeted therapies (e.g., kinase inhibitors) or immune checkpoint-blocking antibodies outperformed conventional chemotherapy, with proven benefit to survival. Nevertheless, primary and acquired resistances as well as adverse events remain limitations of these therapies. Therefore, ADCs appear as an emerging therapeutic option in oncodermatology. After providing an overview of ADC design and development, the goal of this article is to review the potential ADC indications in the field of oncodermatology.
ABSTRACT
BACKGROUND: Low miR-31-3p expression was identified as predictive of anti-EGFR efficacy in RAS-wt mCRC. Primary tumor side was also proposed as a predictive factor of anti-EGFR benefit. This retrospective multicentric study evaluated the predictive role of miR-31-3p in right-sided RAS-wt mCRC patients treated with first-line CT+anti-EGFR or CT+bevacizumab (Beva). METHODS: Seventy-two right-sided RAS-wt mCRC patients treated in first-line with CT+anti-EGFR (n = 43) or Beva (n = 29) were included. Overall survival (OS), progression-free survival (PFS) and response rate (RR) were analyzed and stratified according to tumor miR-31-3p expression level and targeted therapy (TT). RESULTS: BRAF V600E mutation was more frequent in high vs low miR-31-3p expressers (60.6% vs 15.4%, P < 0.001). PFS was significantly longer with CT+Beva than with CT+anti-EGFR (13 vs 7 months; P = 0.024). Among low miR-31-3p expressers, PFS, OS and RR were not significantly different between the two groups, while in high miR-31-3p expressers, only PFS was longer in the CT+Beva group (11 vs 6 months; P = 0.03). In patients treated with CT+anti-EGFR, low miR-31-3p expressers had a significantly longer OS (20 vs 13 months; P = 0.02) than high miR-31-3p expressers. ORR was not significantly different between the two groups of treatment, in both low and high miR-31-3p expressers. MiR-31-3p expression status was statistically correlated between primary tumors and corresponding metastases. CONCLUSION: In this study, miR-31-3p couldn't identify a subgroup of patients with right-sided RAS-wt mCRC who might benefit from anti-EGFR and suggest that Beva is the TT of choice in first-line treatment of these patients.
Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , MicroRNAs , Antineoplastic Combined Chemotherapy Protocols , Bevacizumab/therapeutic use , Colonic Neoplasms/drug therapy , Colonic Neoplasms/genetics , Colorectal Neoplasms/pathology , ErbB Receptors/genetics , Humans , MicroRNAs/genetics , Retrospective StudiesABSTRACT
Colorectal cancer (CRC) is the second leading cause of death worldwide, with 0.9 million deaths per year. The metastatic stage of the disease is identified in about 20% of cases at the first diagnosis and is associated with low patient-survival rates. Voltage-gated sodium channels (NaV) are abnormally overexpressed in several carcinomas including CRC and are strongly associated with the metastatic behavior of cancer cells. Acidification of the extracellular space by Na+/H+ exchangers (NHE) contributes to extracellular matrix degradation and cell invasiveness. In this study, we assessed the expression levels of pore-forming α-subunits of NaV channels and NHE exchangers in tumor and adjacent non-malignant tissues from colorectal cancer patients, CRC cell lines and primary tumor cells. In all cases, SCN5A (gene encoding for NaV1.5) was overexpressed and positively correlated with cancer stage and poor survival prognosis for patients. In addition, we identified an anatomical differential expression of SCN5A and SLC9A1 (gene encoding for NHE-1) being particularly relevant for tumors that originated on the sigmoid colon epithelium. The functional activity of NaV1.5 channels was characterized in CRC cell lines and the primary cells of colon tumors obtained using tumor explant methodologies. Furthermore, we assessed the performance of two new small-molecule NaV1.5 inhibitors on the reduction of sodium currents, as well as showed that silencing SCN5A and SLC9A1 substantially reduced the 2D invasive capabilities of cancer cells. Thus, our findings show that both NaV1.5 and NHE-1 represent two promising targetable membrane proteins against the metastatic progression of CRC.
ABSTRACT
Although virus-negative Merkel cell carcinoma (MCC) is characterized by a high frequency of UV-induced mutations, the expression of two viral oncoproteins is regarded as a key mechanism driving Merkel cell polyomavirusâpositive MCC. The cells in which these molecular events initiate MCC oncogenesis have yet not been identified for both MCC subsets. A considerable proportion of virus-negative MCC is found in association with squamous cell carcinoma (SCC), suggesting (i) coincidental collision, (ii) one providing a niche for the other, or (iii) one evolving from the other. Whole-exome sequencing of four combined tumors consisting of SCC in situ and Merkel cell polyomavirusânegative MCC showed many mutations shared between SCC and MCC in all cases, indicating a common ancestry and thereby a keratinocytic origin of these MCCs. Moreover, analyses of the combined cases as well as of pure SCC and MCC suggest that RB1 inactivation in SCC facilitates MCC development and that epigenetic changes may contribute to the SCC/MCC transition.
Subject(s)
Carcinoma in Situ , Carcinoma, Merkel Cell , Carcinoma, Squamous Cell , Merkel cell polyomavirus , Skin Neoplasms , Carcinoma, Merkel Cell/genetics , Carcinoma, Merkel Cell/pathology , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Humans , Merkel cell polyomavirus/genetics , Skin Neoplasms/genetics , Skin Neoplasms/pathologyABSTRACT
Inflammation, oxidative stress, and protease/protease inhibitor imbalance with excessive production of proteases are factors associated with pathogenesis of the chronic obstructive pulmonary disease (COPD). In this study, we report that kallikrein-related peptidase 5 (KLK5) is a crucial protease involved in extracellular matrix (ECM) remodeling and bronchial epithelial repair after injury. First, we showed that KLK5 degrades the basal layer formed by culture of primary bronchial epithelial cells from COPD or non-COPD patients. Also, exogenous KLK5 acted differently on BEAS-2B cells already engaged in epithelial-to-mesenchymal transition (EMT) or on 16HBE 14o- cells harboring epithelial characteristics. Indeed, by inducing EMT, KLK5 reduced BEAS-2B cell adherence to the ECM. This effect, neutralized by tissue factor pathway inhibitor 2, a kunitz-type serine protease inhibitor, was due to a direct proteolytic activity of KLK5 on E-cadherin, ß-catenin, fibronectin, and α5ß1 integrin. Thus, KLK5 may strengthen EMT mechanisms and promote the migration of cells by activating the mitogen-activated protein kinase signaling pathway required for this function. In contrast, knockdown of endogenous KLK5 in 16HBE14o- cells, accelerated wound healing repair after injury, and exogenous KLK5 addition delayed the closure repair. These data suggest that among proteases, KLK5 could play a critical role in airway remodeling events associated with COPD during exposure of the pulmonary epithelium to inhaled irritants or smoking and the inflammation process.
Subject(s)
Airway Remodeling , Bronchi/pathology , Epithelial Cells/pathology , Epithelial-Mesenchymal Transition , Kallikreins/metabolism , Lung Neoplasms/pathology , Pulmonary Disease, Chronic Obstructive/pathology , Aged , Antigens, CD/genetics , Antigens, CD/metabolism , Bronchi/metabolism , Cadherins/genetics , Cadherins/metabolism , Case-Control Studies , Cells, Cultured , Epithelial Cells/metabolism , Female , Humans , Kallikreins/genetics , Lung Neoplasms/metabolism , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/metabolism , Signal TransductionABSTRACT
Setmar is a gene specific to simian genomes. The function(s) of its isoforms are poorly understood and their existence in healthy tissues remains to be validated. Here we profiled SETMAR expression and its genome-wide binding landscape in colon tissue. We found isoforms V3 and V6 in healthy and tumour colon tissues as well as incell lines. In two colorectal cell lines SETMAR binds to several thousand Hsmar1 and MADE1 terminal ends, transposons mostly located in non-genic regions of active chromatin including in enhancers. It also binds to a 12-bp motifs similar to an inner motif in Hsmar1 and MADE1 terminal ends. This motif is interspersed throughout the genome and is enriched in GC-rich regions as well as in CpG islands that contain constitutive replication origins. It is also found in enhancers other than those associated with Hsmar1 and MADE1. The role of SETMAR in the expression of genes, DNA replication and in DNA repair are discussed.