Myoepithelial neoplasms of the skin and soft tissue still represent a confusing and somewhat controversial field in pathology as it appears that this category includes several different entities. However, recent studies have suggested that both apocrine mixed tumors (AMT) and cutaneous myoepitheliomas (CM) harbor identical chromosomal rearrangements involving the PLAG1 gene and hence may represent a morphological spectrum. The aim of the present study was to share our institutional experience with these tumors and specifically focus on studying their immunohistochemical and molecular features to further assess their relatedness. Eleven cases of AMT and 7 cases of CM were collected and analyzed using immunohistochemistry (IHC), PLAG1 FISH, and Archer FusionPlex assay. There were 14 male and 4 female patients with ages ranging from 26 to 85 years (median 55.8 years, mean 58.5 years). AMTs were mainly located in the head and neck (n = 10), while CMs were mainly located in the acral sites (n = 5). PLAG1 IHC was diffusely strongly positive in 14/17 (82%) cases, whereas a single case of AMT diffusely expressed HMGA2. Both tumor groups showed PLAG1 gene fusions which were detected in 6/13 analyzable samples (AMT, n = 4 and CM, n = 2), and included TRPS1::PLAG1 (n = 3), NDRG1::PLAG1 (n = 1), CTNNB1::PLAG1 (n = 1) and a novel PXDNL::PLAG1 fusion (n = 1). The remaining 5 cases were negative, 5 were not analyzable and the single case positive for HMGA2 by IHC revealed a potential HMGA2 gene rearrangement. The cases were further studied by FISH, with 12/17 cases showing PLAG1 gene rearrangement (AMT, n = 8 and CM, n = 4). Altogether, 14/18 cases showed PLAG1 gene rearrangement by at least one of the methods. PLAG1 immunohistochemistry had a 92% specificity and sensitivity. Our study provided additional data to suggest that AMT and CM share overlapping morphological and immunohistochemical features as well as molecular background characterized by PLAG1 gene fusions and thus represent a morphological spectrum. In addition, we identified a novel PXDNL::PLAG1 fusion and suggested that rare cases may harbor HMGA2 gene alterations which seem to be mutually exclusive with PLAG1 gene fusions. The relatedness of these tumors to salivary gland myoepithelial neoplasms and distinctness from eccrine mixed tumors and other skin and soft tissue myoepithelial neoplasms with EWSR1/FUS fusions is discussed.

• MeSH
• DNA-Binding Proteins * genetics   MeSH
• Adult MeSH
• Gene Rearrangement * MeSH
• In Situ Hybridization, Fluorescence MeSH
• Immunohistochemistry * MeSH
• Middle Aged MeSH
• Humans MeSH
• Myoepithelioma * genetics   pathology   MeSH
• Biomarkers, Tumor * genetics   analysis   MeSH
• Neoplasms, Complex and Mixed genetics   pathology   chemistry   MeSH
• Skin Neoplasms * genetics   pathology   MeSH
• Sweat Gland Neoplasms genetics   pathology   MeSH
• HMGA2 Protein * genetics   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

Three main uterine leiomyoma molecular subtypes include tumors with MED12 mutation, molecular aberrations leading to HMGA2 overexpression, and biallelic loss of FH. These aberrations are mutually exclusive and can be found in approximately 80-90% of uterine leiomyoma, in which they seem to be a driver event. Approximately 10% of uterine leiomyoma, however, does not belong to any of these categories. Uterine leiomyoma with HMGA2 overexpression is the most common subtype in cellular and second most common category of usual leiomyoma. In some of these tumors, rearrangement of HMGA2 gene is present. The most common fusion partner of HMGA2 gene is RAD51B. Limited data suggests that RAD51B fusions with other genes may be present in uterine leiomyoma. In our study, we described two cases of uterine leiomyoma with RAD51B::NUDT3 fusion, which occur in one case of usual and one case of highly cellular leiomyoma. In both cases, no other driver molecular aberrations were found. The results of our study showed that RAD51::NUDT3 fusion can occur in both usual and cellular leiomyoma. RAD51B may be a fusion partner of multiple genes other than HMGA2 and HMGA1. In these cases, RAD51B fusion seems to be mutually exclusive with other driver aberrations defining molecular leiomyoma subtypes. RAD51B::NUDT3 fusion should be added to the spectrum of fusions which may occur in uterine leiomyoma, which can be of value especially in cellular leiomyoma in the context of differential diagnosis against endometrial stromal tumors.

• MeSH
• DNA-Binding Proteins * genetics   MeSH
• Adult MeSH
• Oncogene Proteins, Fusion genetics   MeSH
• Leiomyoma * genetics   pathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Biomarkers, Tumor genetics   MeSH
• Uterine Neoplasms * genetics   pathology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH

INTRODUCTION: Among children born small for gestational age, 10-15% fail to catch up and remain short (SGA-SS). The underlying mechanisms are mostly unknown. We aimed to decipher genetic aetiologies of SGA-SS within a large single-centre cohort. METHODS: Out of 820 patients treated with growth hormone (GH), 256 were classified as SGA-SS (birth length and/or birth weight <-2 SD for gestational age and life-minimum height <-2.5 SD). Those with the DNA triplet available (child and both parents) were included in the study (176/256). Targeted testing (karyotype/FISH/MLPA/specific Sanger sequencing) was performed if a specific genetic disorder was clinically suggestive. All remaining patients underwent MS-MLPA to identify Silver-Russell syndrome, and those with unknown genetic aetiology were subsequently examined using whole-exome sequencing or targeted panel of 398 growth-related genes. Genetic variants were classified using ACMG guidelines. RESULTS: The genetic aetiology was elucidated in 74/176 (42%) children. Of these, 12/74 (16%) had pathogenic or likely pathogenic (P/LP) gene variants affecting pituitary development (LHX4, OTX2, PROKR2, PTCH1, POU1F1), the GH-IGF-1 or IGF-2 axis (GHSR, IGFALS, IGF1R, STAT3, HMGA2), 2/74 (3%) the thyroid axis (TRHR, THRA), 17/74 (23%) the cartilaginous matrix (ACAN, various collagens, FLNB, MATN3), and 7/74 (9%) the paracrine chondrocyte regulation (FGFR3, FGFR2, NPR2). In 12/74 (16%), we revealed P/LP affecting fundamental intracellular/intranuclear processes (CDC42, KMT2D, LMNA, NSD1, PTPN11, SRCAP, SON, SOS1, SOX9, TLK2). SHOX deficiency was found in 7/74 (9%), Silver-Russell syndrome in 12/74 (16%) (11p15, UPD7), and miscellaneous chromosomal aberrations in 5/74 (7%) children. CONCLUSIONS: The high diagnostic yield sheds a new light on the genetic landscape of SGA-SS, with a central role for the growth plate with substantial contributions from the GH-IGF-1 and thyroid axes and intracellular regulation and signalling.

• MeSH
• Child MeSH
• Gestational Age MeSH
• Infant, Small for Gestational Age MeSH
• Insulin-Like Growth Factor I MeSH
• Humans MeSH
• Human Growth Hormone * genetics   MeSH
• Dwarfism * MeSH
• Infant, Newborn MeSH
• Growth Disorders genetics   diagnosis   MeSH
• Short Stature Homeobox Protein MeSH
• Silver-Russell Syndrome * genetics   MeSH
• Body Height genetics   MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Infant, Newborn MeSH
• Publication type
• Journal Article MeSH

AIMS: The formal pathogenesis of salivary carcinosarcoma (SCS) remained unclear, both with respect to the hypothetical development from either preexisting pleomorphic adenoma (PA) or de novo and the clonal relationship between highly heterogeneous carcinomatous and sarcomatous components. METHODS AND RESULTS: We performed clinicopathological and molecular (targeted RNA sequencing) analyses on a large series of 16 cases and combined this with a comprehensive literature search (111 cases). Extensive sampling (average 11.6 blocks), combined with immunohistochemistry and molecular studies (PA-specific translocations including PLAG1 or HMGA2 proven in 6/16 cases), enabled the morphogenetic identification of PA in 15/16 cases (93.8%), by far surpassing a reported rate of 49.6%. Furthermore, we demonstrated a multistep (intraductal/intracapsular/extracapsular) adenoma-carcinoma-sarcoma-progression, based on two alternative histogenetic pathways (intraductal, 56.3%, versus myoepithelial pathway, 37.5%). Thereby, early intracapsular stages are identical to conventional carcinoma ex PA, while later extracapsular stages are dominated by secondary, frequently heterologous sarcomatous transformation with often large tumour size (>60 mm). CONCLUSION: Our findings strongly indicate that SCS (almost) always develops from PA, with a complex multistep adenoma-carcinoma-sarcoma-sequence, based on two alternative histogenetic pathways. The findings from this novel approach strongly suggest that SCS pathogenetically is a rare (3-6%), unique, and aggressive variant of carcinoma ex PA with secondary sarcomatous overgrowth. In analogy to changes of terminology in other organs, the term "sarcomatoid carcinoma ex PA with/without heterologous elements" might be more appropriate.

• MeSH
• Adenocarcinoma * MeSH
• In Situ Hybridization, Fluorescence MeSH
• Carcinosarcoma * MeSH
• Humans MeSH
• Biomarkers, Tumor genetics   MeSH
• Soft Tissue Neoplasms * MeSH
• Salivary Gland Neoplasms * pathology   MeSH
• Adenoma, Pleomorphic * pathology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

Cellular leiomyoma (CL) represents an uncommon variant of uterine leiomyoma with limited data concerning its immunohistochemical and molecular profile. We performed a comprehensive analysis of 52 CL cases all of which were analyzed immunohistochemically. Molecular analysis was possible in 32 cases with sufficient DNA, and 38 cases with sufficient RNA. The immunohistochemical results showed a high expression of smooth muscle markers (calponin (100%), desmin (100%), smooth muscle actin (98.1%), caldesmon (96.1%), transgelin (96.1%), smooth muscle myosin heavy chain (86.5%), and smoothelin (61.5%)). Concerning markers of endometrial stromal differentiation, the expression of CD10 was observed in 65.4% cases (42.2% with H-score > 50), and IFITM1 in 36.5% cases (1.9% with H-score > 50). 36.5% showed HMGA2 overexpression at the IHC level, associated with increased mRNA expression in 14/14 cases. The rearrangement of the HMGA2 gene was detected in 13.2%. Chromosome 1p deletion was found in 19.3%, while 9.4% of tumors showed a pathogenic mutation in the MED12 gene. In conclusion, CL is immunohistochemically characterized by a high expression of "smooth muscle" markers commonly associated with a co-expression of "endometrial stromal" markers, where IFITM1 shows superior performance compared to CD10 regarding its specificity for differentiation from endometrial stromal tumors. The sensitivity of smoothelin in CL seems rather low, but no data is available to assess its specificity. On a molecular level, the most common mutually exclusive aberration in CL affects HMGA2, followed by chromosome 1p deletions and MED12 mutations.

• MeSH
• Chromosomes chemistry   metabolism   MeSH
• Leiomyoma * pathology   MeSH
• Humans MeSH
• Mediator Complex genetics   metabolism   MeSH
• Mutation MeSH
• Uterine Neoplasms * pathology   MeSH
• Endometrial Neoplasms * genetics   MeSH
• Neprilysin analysis   MeSH
• HMGA2 Protein MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Salivary gland tumors are a heterogeneous group of tumors originating from the major and minor salivary glands. The pleomorphic adenoma (PA), which is the most common subtype, is a benign lesion showing a remarkable morphologic diversity and that, upon recurrence or malignant transformation, can cause significant clinical problems. Cytogenetic studies of >500 PAs have revealed a complex and recurrent pattern of chromosome rearrangements. In this review, we discuss the specificity and frequency of these rearrangements and their molecular/clinical consequences. The genomic hallmark of PA is translocations with breakpoints in 8q12 and 12q13-15 resulting in gene fusions involving the transcription factor genes PLAG1 and HMGA2. Until recently, the association between these two oncogenic drivers was obscure. Studies of the Silver-Russel syndrome, a growth retardation condition infrequently caused by mutations in IGF2/HMGA2/PLAG1, have provided new clues to the understanding of the molecular pathogenesis of PA. These studies have demonstrated that HMGA2 is an upstream regulator of PLAG1 and that HMGA2 regulates the expression of IGF2 via PLAG1. This provides a novel explanation for the 8q12/12q13-15 aberrations in PA and identifies IGF2 as a major oncogenic driver and therapeutic target in PA. These studies have important diagnostic and therapeutic implications for patients with PA.

• Publication type
• Journal Article MeSH
• Review MeSH

Most of salivary gland neoplasms (benign and malignant) are characterized by recurrent gene fusions. Pleomorphic adenoma (PA), the most frequent salivary gland tumor, is driven by chromosomal rearrangements involving PLAG1 mapped to 8q12 and HMGA2 mapped to 12q13-15 in most cases. Multiple fusion partners have been identified including CTNNB1, FGFR1, LIFR, CHCHD7 and TCEA for PLAG1 fusions and NFIB, WIF1 and FHIT for HMGA2 fusions. To date, no data exist on the morphology of the few reported HMGA2-WIF1-rearranged PAs. We present 28 major salivary gland adenomas displaying distinctive trabecular and canalicular morphology associated with recurrent genotype. Patients were 15 females and 13 males aged 43 to 87 (median: 65). All tumors originated from the parotid. Their size range was 1 to 4 cm (mean: 2.3). Histologically, all tumors showed elongated or columnar cells arranged into bilayered to multilayered communicating and branching strands and trabeculae in a manner similar to canalicular adenoma of minor salivary glands or trabecular myoepithelioma with variable solid confluent intercalated duct-like areas. Fifteen tumors were exclusively canalicular/trabecular while 13 had intermingled or well-demarcated conventional (chondromyxoid) PA component comprising 5 to >50% of the tumor. The monomorphic areas expressed uniformly CK7 (28/28), vimentin (21/21), S100 (24/24), SOX10 (16/17) and variably p63 (8/21) and mammaglobin (6/16) but were negative with p40 (0/24), smooth muscle actin (0/24) and MUC4 (0/16). Targeted RNA sequencing revealed HMGA2 fusions in 14/16 (87%) assessable cases. Fusion partner was WIF1 (12), RPSAP52 (1) and HELB (1). Separate testing of the 2 components in 1 hybrid tumor showed same HMGA2/WIF1 fusion. HMGA2 immunohistochemistry was homogeneously positive in all cases including the 2 fusion-negative cases. A control cohort of 12 genuine canalicular adenomas revealed no HMGA2 fusions (0/4) and lacked HMGA2 immunoreactivity (0/12). This study highlights a distinctive variant in the spectrum of PA characterized by prominent trabecular and canalicular adenoma-like morphology. Our data confirm that canalicular adenomas in major salivary glands (either monomorphic or part of hybrid tumors) are distinct from canalicular adenoma of minor salivary glands. Their uniform genotype irrespective of presence or absence of a conventional PA component argues for classifying those tumors lacking a conventional PA component as "monomorphic variants of PA" rather than canalicular/basal cell adenomas, intercalated duct adenoma, trabecular myoepithelioma or true hybrid tumors.

• MeSH
• Adaptor Proteins, Signal Transducing genetics   MeSH
• Adult MeSH
• Gene Fusion * MeSH
• Gene Rearrangement * MeSH
• Middle Aged MeSH
• Humans MeSH
• Biomarkers, Tumor analysis   genetics   MeSH
• Salivary Gland Neoplasms chemistry   genetics   pathology   MeSH
• Adenoma, Pleomorphic chemistry   genetics   pathology   MeSH
• HMGA2 Protein genetics   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Giant cell tumors of soft tissue (GCT-ST) are rare low-grade neoplasms that were at one time thought to represent the soft tissue counterparts of GCT of bone (GCT-B) but are now known to lack the H3F3 mutations characteristic of osseous GCT. We present six distinctive giant cell-rich soft tissue neoplasms that expressed keratins and carried a recurrent HMGA2-NCOR2 gene fusion. Patients were five females and one male aged 14-60 years (median, 29). All presented with superficial (subcutaneous) masses that were removed by conservative marginal (3) or wide (2) local excision. The tumors originated in the upper extremity (2), lower extremity (2), head/neck (1), and trunk (1). Five patients with follow-up (median, 21 months; range, 14-168) remained disease-free. Grossly, all tumors were well-demarcated but not encapsulated with variable lobulation. Histologically, they were composed of bland plump epithelioid or ovoid to spindled mononuclear cells admixed with evenly distributed multinucleated osteoclast-type giant cells. Foci of stromal hemorrhage and hemosiderin were seen in all cases. The mitotic activity ranged from 2 to 14/10 high power fields (median: 10). Foci of necrosis and vascular invasion were seen in one case each. The mononuclear cells were immunoreactive with the AE1/AE3 keratin cocktail and less frequently/less diffusely for K7 and K19 but lacked expression of other lineage-associated markers. RNA-based next-generation sequencing revealed an HMGA2-NCOR2 fusion in all tumors. None of the keratin-negative conventional GCT-ST showed the HMGA2-NCOR2 fusion (0/7). Metaplastic bone (4/9) and SATB2 expression (3/4) were frequent in keratin-negative conventional GCT-ST but were lacking in keratin-positive HMGA2-NCOR2 fusion-positive tumors. The distinctive immunophenotype and genotype of these tumors strongly suggest that they represent a discrete entity, differing from conventional GCT-ST and other osteoclast-rich morphologic mimics. Their natural history appears favorable, although a study of additional cases and longer follow-up are warranted.

• MeSH
• Child MeSH
• Adult MeSH
• Keratins MeSH
• Nuclear Receptor Co-Repressor 2 genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Soft Tissue Neoplasms genetics   pathology   MeSH
• Giant Cell Tumors genetics   pathology   MeSH
• Oncogene Fusion MeSH
• HMGA2 Protein genetics   MeSH
• Aged MeSH
• Check Tag
• Child MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Projekt je zaměřen na detailní analýzu exprese pěti kandidátních biomarkerů (PBX1, HOXC9, NF1, HMGI-C a HMGA2), které souvisejí s rezistencí k retinoidům v buňkách neuroblastomu. Endogenní exprese těchto biomarkerů bude hodnocena pomocí PCR a imunodetekce ve stabilizovaných neuroblastomových buněčných liniích a v párových vzorcích nádorové tkáně od jednotlivých pacientů. Do studie bude zařazeno nejméně 25-30 párových vzorků nádorové tkáně odebírané pacientům a 25 neuroblastomových buněčných linií. Případné rozdíly v expresi biomarkerů mezi párovými vzorky téhož pacienta, které byly odebrány v době diagnózy a po indukční chemoterapii, budou ověřeny pomocí ovlivnění buněčných linií vybranými retinoidy. Tato studie přinese zejména zcela nové poznatky založené na komplexní analýze všech kandidátních biomarkerů rezistence k retinoidům v rámci jedné experimentální kohorty. Získané informace tak mohou přispět k identifikaci prediktivních biomarkerů, které budou v praxi využitelné ke stanovení léčebné odpovědi na retinoidy u pacientů s vysoce rizikovými neuroblastomy.; This project is aimed at a detailed analysis of the expression of five candidate biomarkers (PBX1, HOXC9, NF1, HMGI-C and HMGA2) associated with the resistance to retinoids in neuroblastoma cells. Endogenous expression of these biomarkers should be evaluated in established neuroblastoma cell lines as well as in paired samples of tumor tissue taken from the individual patients using PCR and immunodetection methods. At least 25-30 paired tumor samples and 25 neuroblastoma cell lines should be included in this study. Possible differences in expression of biomarkers between paired samples taken from the same patient at diagnosis and after induction chemotherapy should be verified on cell lines treated with selected retinoids. This study brings especially completely new information based on multiple analysis of all candidate biomarkers known to be associated with the resistance to retinoids in one experimental cohort. Obtained data may help to identify useful predictive biomarkers of the patient’s response to retinoids within high-risk neuroblastoma category.

• MeSH
• Bexarotene MeSH
• Drug Resistance, Neoplasm MeSH
• Fenretinide MeSH
• Immunologic Techniques MeSH
• Biomarkers, Tumor MeSH
• Neuroblastoma MeSH
• Neurofibromin 1 chemistry   MeSH
• Reverse Transcriptase Polymerase Chain Reaction MeSH
• Pre-B-Cell Leukemia Transcription Factor 1 chemistry   MeSH
• HMGA Proteins chemistry   MeSH
• Retinoids MeSH

• Conspectus
• Patologie. Klinická medicína
• NML Fields
• onkologie
• pediatrie
• chemie, klinická chemie
• NML Publication type
• závěrečné zprávy o řešení grantu AZV MZ ČR

CONTEXT: Familial short stature (FSS) is a term describing a growth disorder that is vertically transmitted. Milder forms may result from the combined effect of multiple genes; more severe short stature is suggestive of a monogenic condition. The etiology of most FSS cases has not been thoroughly elucidated to date. OBJECTIVES: To identify the genetic etiology of severe FSS in children treated with GH because of the diagnosis of small for gestational age or GH deficiency (SGA/GHD). DESIGN, SETTINGS, AND PATIENTS: Of 736 children treated with GH because of GHD/SGA, 33 with severe FSS (life-minimum height -2.5 SD or less in both the patient and shorter parent) were included in the study. The genetic etiology was known in 5 of 33 children prior to the study [ACAN (in 2], NF1, PTPN11, and SOS1). In the remaining 28 of 33, whole-exome sequencing was performed. The results were evaluated using American College of Medical Genetics and Genomics standards and guidelines. RESULTS: In 30 of 33 children (90%), we found at least one variant with potential clinical significance in genes known to affect growth. A genetic cause was elucidated in 17 of 33 (52%). Of these children, variants in growth plate-related genes were found in 9 of 17 [COL2A1, COL11A1, and ACAN (all in 2), FLNB, FGFR3, and IGF1R], and IGF-associated proteins were affected in 2 of 17 (IGFALS and HMGA2). In the remaining 6 of 17, the discovered genetic mechanisms were miscellaneous (TRHR, MBTPS2, GHSR, NF1, PTPN11, and SOS1). CONCLUSIONS: Single-gene variants are frequent among families with severe FSS, with variants affecting the growth plate being the most prevalent.

• MeSH
• Child MeSH
• Genetic Predisposition to Disease epidemiology   MeSH
• Genetic Variation * MeSH
• Cohort Studies MeSH
• Infant MeSH
• Humans MeSH
• Human Growth Hormone therapeutic use   MeSH
• Metalloendopeptidases genetics   MeSH
• Adolescent MeSH
• Growth Disorders drug therapy   epidemiology   genetics   MeSH
• Child, Preschool MeSH
• Prognosis MeSH
• Prospective Studies MeSH
• Receptor, Fibroblast Growth Factor, Type 3 genetics   MeSH
• Receptor, IGF Type 1 genetics   MeSH
• Pedigree MeSH
• Growth Plate drug effects   MeSH
• Exome Sequencing methods   MeSH
• Severity of Illness Index MeSH
• Treatment Outcome MeSH
• Check Tag
• Child MeSH
• Infant MeSH
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH