Prokopios P. Argyris

Fluorescence in‐situ hybridization identifies Mastermind‐like 2 (MAML2) rearrangement in odontogenic cysts with mucous prosoplasia: a pilot study

The pathogenesis of intraosseous mucoepidermoid carcinoma (IMEC) remains unknown. Coexistence with odontogenic cysts (ODC) has been reported in 32–48% of IMEC. Furthermore, prosoplastic mucous cells are often seen in the epithelial lining of ODCs. MECT1–MAML2 fusion transcripts have been identified in >66% of salivary gland MEC cases. The aim of this study was to investigate the presence of MAML2 rearrangement in ODCs featuring mucous prosoplasia.

S100A8/A9 regulates MMP-2 expression and invasion and migration by carcinoma cells

Intracellular calprotectin (S100A8/A9) functions in the control of the cell cycle checkpoint at G2/M. Dysregulation of S100A8/A9 appears to cause loss of the checkpoint, which frequently characterizes head and neck squamous cell carcinoma (HNSCC). In the present study, we analyzed carcinoma cells for other S100A8/A9-directed changes in malignant phenotype. Using a S100A8/A9-negative human carcinoma cell line (KB), transfection to express S100A8 and S100A9 caused selective down-regulation of MMP-2 and inhibited in vitro invasion and migration. Conversely, silencing of endogenous S100A8 and S100A9 expression in TR146 cells, a well-differentiated HNSCC cell line, increased MMP-2 activity and in vitro invasion and migration. When MMP-2 expression was silenced, cells appeared to assume a less malignant phenotype. To more closely model the architecture of cell growth in vivo, cells were grown in a 3D collagen substrate, which was compared to 2D. Growth on 3D substrates caused greater MMP-2 expression. Whereas hypermethylation of CpG islands occurs frequently in HNSCC, S100A8/A9-dependent regulation of MMP-2 could not be explained by modification of the upstream promoters of MMP2 or TIMP2. Collectively, these results suggest that intracellular S100A8/A9 contributes to the cancer cell phenotype by modulating MMP-2 expression and activity to regulate cell migration and mobility.

Clinical utility of myb rearrangement detection and p63/p40 immunophenotyping in the diagnosis of adenoid cystic carcinoma of minor salivary glands: a pilot study

OBJECTIVES MYB rearrangement is observed in approximately 28% to 86% of adenoid cystic carcinomas (ACCs). Also, ACC features a p63+/p40+ immunophenotype in greater than 90% of cases, compared with p63+/p40- polymorphous low-grade adenocarcinoma (PLGA). Our aim was to investigate the incidence of (1) MYB rearrangement and (2) p63/p40 immunoreactivity in ACC and PLGA of minor salivary glands (MSGs). STUDY DESIGN Seven cases of ACC as well as five of PLGA were evaluated by using a MYB (6 q23.3) break-apart fluorescence in situ hybridization (FISH) probe. In addition, all cases were immunohistochemically stained with p63 and p40 antibodies. RESULTS All five successfully hybridized ACCs featured MYB rearrangement, whereas PLGAs did not show MYB rearrangement. Interestingly, one case of PLGA demonstrated a single intact copy of MYB in greater than 88% of the neoplastic cells. All ACCs exhibited consistent p63+/p40+ staining, whereas PLGAs demonstrated a p63+/p40- immunophenotype. CONCLUSIONS (1) MYB rearrangement is encountered in ACCs but not PLGAs of MSGs; (2) MYB aberrations, for example, monosomy or deletion, can be seen in PLGAs; (3) combined p63/p40 immunostaining can be used to differentiate ACC from PLGA in incisionally biopsied specimens; and (4) performance of either FISH or p63/p40 immunohistochemistry is expected to be able to confirm the diagnosis of ACC or PLGA in small intraoral biopsies, since both techniques appeared to be diagnostically accurate in this pilot study.

Localized juvenile spongiotic gingival hyperplasia featuring unusual p16INK4A labeling and negative human papillomavirus status by polymerase chain reaction.

BACKGROUND Localized juvenile spongiotic gingival hyperplasia (LJSGH) is a distinct type of gingival hyperplastic lesion with specific clinicopathologic features. Evaluation of the morphological characteristics of LJSGH indicates the potential role of human papillomavirus (HPV) infection as an underlying etiopathogenetic mechanism. METHODS All cases of LJSGH from 2008 to present were retrieved. Clinical and demographic data were collected. HPV status was investigated by p16INK4A immunohistochemistry and HPV-Polymerase chain reaction (PCR). RESULTS Twenty-one cases of LJSGH were identified, 14 (66.7%) affecting males and seven (33.3%) females (M:F = 2:1, age range: 8-36, mean: 13 years). All lesions were well-demarcated, exophytic, erythematous, and hemorrhagic with granular or slightly papillary surface. Preponderance for the maxillary gingiva (19, 90.5%) was observed. Two (9.5%) patients presented with recurrence 20 and 21 months after excision (mean follow-up: 18.7 months). Histopathologically, all LJSGH lesions featured epithelial hyperplasia with intense neutrophilic exocytosis and spongiosis. All cases demonstrated positivity for p16INK4A with the majority of specimens (47.6%) intensely decorated in >50% of the overlying epithelium with focal immunostaining observed in 47.6% and diffuse in 52.4%. Thirteen cases (61.9%) were negative for HPV DNA by PCR, while two (9.5%) were suspicious for the presence of low levels of HPV DNA but definitive genotyping was not possible. One case (4.8%) displayed positivity for HPV-31. The remaining five cases failed the PCR reaction. CONCLUSIONS Human papillomavirus does not participate in the pathogenesis of LJSGH. P16INK4A expression in the absence of detectable HPV DNA can likely be attributed to the intense inflammation associated with LJSGH.

Nasopharyngeal hyalinizing clear cell carcinoma: Report of the histopathologic features of a case showing ewsr1 rearrangements by fish and literature review

Background. Hyalinizing clear cell carcinoma (HCCC) is a rare low-grade malignant tumor affecting the minor salivary glands; nasopharyngeal involvement is uncommon. Methods and Results. A 38-year-old male patient presented with a 3.2 × 4.5 × 4.4 cm expansile mass obliterating the lumen of the nasopharynx and extending into the left nasal cavity. Histopathologically, the tumor was characterized by clear round to polygonal epithelial cells arranged in anastomosing trabeculae and solid nests. The stroma consisted of fibromyxoid connective tissue with areas of intense hyalinization and desmoplasia. Immunohistochemically, strong and diffuse reactivity for AE1/AE3, CK5/6, and p63 was observed. EWSR1 gene rearrangement was confirmed by fluorescence in situ hybridization. The diagnosis of nasopharyngeal HCCC was rendered. Surgical excision was performed along with adjuvant radiotherapy and chemotherapy. Conclusions. HCCC generally demonstrates good prognosis with low metastatic potential. Identification of EWSR1 gene disruption is useful in discerning HCCC from other neoplasms with overlapping microscopic features.

A subset of ectomesenchymal chondromyxoid tumours of the tongue show EWSR1 rearrangements and are genetically linked to soft tissue myoepithelial neoplasms: a study of 11 cases

Ectomesenchymal chondromyxoid tumour (ECT) is a rare, benign intraoral neoplasm showing a predilection for the anterior dorsum of the tongue. The World Health Organization includes ECT in the pathological spectrum of soft tissue myoepithelioma. EWS RNA‐binding protein 1 gene (EWSR1) rearrangement is found in 45% of cutaneous, soft tissue and bone myoepithelial neoplasms, and pleomorphic adenoma gene 1 (PLAG1) aberrations are found in 37% of EWSR1‐negative soft tissue myoepitheliomas. The aim of this study was to evaluate the presence of EWSR1 and PLAG1 rearrangements in ECTs.

Maxillary pseudotumor as initial manifestation of von Willebrand disease, type 2: report of a rare case and literature review.

OBJECTIVES Von Willebrand disease (VWD) is a bleeding disorder associated with inherited defects of von Willebrand factor (VWF). Type 2 N VWD is characterized by impaired FVIII-binding capacity (VWF:FVIIIB). Pseudotumor (PT) represents a serious complication of hemophilia. Case reports of oral PTs in VWD remain scarce. METHODS An 11-year-old Caucasian female presented with an expansile gingival mass of the posterior maxilla. Surgical excision of the tumor was performed. RESULTS Histopathologically, the tumor was characterized by cystic spaces filled with hemorrhagic material and dense fibrous connective tissue. Postoperatively, the patient suffered prolonged hemorrhage. Results of blood tests showed decreased levels of FVIII function ( FVIII C) and VWF:FVIIIB. Subsequent gene analysis for type 2 N VWD confirmed heterozygosity for the missense mutation p.Arg816 Trp. A diagnosis of oral PT was rendered. CONCLUSIONS Here, we report the clinical, radiographic, and microscopic features of a rare example of oral PT leading to the diagnosis of type 2 N VWD.

Polymorphous low-grade adenocarcinoma of the upper lip with metachronous myoepithelioma of the buccal mucosa

Examples of multiple minor salivary gland tumors, synchronous or metachronous, are uncommon. We report a patient who initially presented with polymorphous low-grade adenocarcinoma (PLGA) and subsequently with myoepithelioma. A 91-year-old white woman presented in 2009 with a 1-cm, firm, nontender, well-circumscribed nodule of the left side of the upper lip extending to the anterior buccal mucosa. Excisional biopsy revealed PLGA. While the margins were positive, further treatment was not recommended due to the patients age. In 2011, the patient returned with a 1.5-cm, asymptomatic mass of the left buccal vestibule. Excision of the lesion revealed a circumscribed proliferation of epithelioid and plasmacytoid cells arranged in spherical or whorl-like islands and immersed in a mucinous stroma, consistent with myoepithelioma. The PLGA recurred 3 years after initial diagnosis. Excision was again associated with positive margins, and again no further treatment was recommended. A few months later, at a scheduled follow-up appointment, she presented with a painless nodule of the left upper lip, consistent with recurrent PLGA. One month later, the patient died of unrelated causes. We also present a literature review of multiple minor salivary gland tumors.

Calprotectin and the Initiation and Progression of Head and Neck Cancer

Calprotectin (S100A8/A9), a heterodimeric complex of calcium-binding proteins S100A8 and S100A9, is encoded by genes mapping to the chromosomal locus 1q21.3 of the epidermal differentiation complex. Whereas extracellular calprotectin shows proinflammatory and antimicrobial properties by signaling through RAGE and TLR4, intracytoplasmic S100A8/A9 appears to be important for cellular development, maintenance, and survival. S100A8/A9 is constitutively expressed in myeloid cells and the stratified mucosal epithelia lining the oropharyngeal and genitourinary mucosae. While upregulated in adenocarcinomas and other cancers, calprotectin mRNA and protein levels decline in head and neck squamous cell carcinoma (HNSCC). S100A8/A9 is also lost during head and neck preneoplasia (dysplasia). Calprotectin decrease does not correlate with the clinical stage (TNM) of HNSCC. When expressed in carcinoma cells, S100A8/A9 downregulates matrix metalloproteinase 2 expression and inhibits invasion and migration in vitro. S100A8/A9 regulates cell cycle progression and decelerates cancer cell proliferation by arresting at the G2/M checkpoint in a protein phosphatase 2α–dependent manner. In HNSCC, S100A8 and S100A9 coregulate with gene networks controlling cellular development and differentiation, cell-to-cell signaling, and cell morphology, while S100A8/A9 appears to downregulate expression of invasion- and tumorigenesis-associated genes. Indeed, tumor formation capacity is attenuated in S100A8/A9-expressing carcinoma cells in vivo. Hence, intracellular calprotectin appears to function as a tumor suppressor in head and neck carcinogenesis. When compared with S100A8/A9-low HNSCC based on analysis of TCGA, S100A8/A9-high HNSCC shows significant upregulation of apoptosis-related genes, including multiple caspases. Accordingly, S100A8/A9 facilitates DNA damage responses in HNSCC, promotes apoptotic cell death, and confers sensitivity to cisplatin and X-radiation in vitro. In the tumor milieu, loss of S100A8/A9 strongly associates with poor squamous differentiation and higher tumor grading, EGFR upregulation, increased DNA methylation, and, finally, poorer overall survival for patients with HNSCC. Hence, intracellular calprotectin shows a multifaceted protective role against the development of HNSCC.

Angioimmunoblastic T-cell lymphoma of the oral cavity presenting as gingival mass: report of the histopathologic and molecular characteristics of an unusual case featuring clonal T-cell receptor γ gene rearrangement by polymerase chain reaction

Angioimmunoblastic T-cell lymphoma (AITL) is a rare neoplastic process constituting 15% to 20% of peripheral T-cell lymphomas. We report the clinicopathologic and molecular characteristics of an unusual intraoral manifestation of AITL. A 35-year-old white man with a history of AITL presented with a 2.5-cm, poorly circumscribed, erythematous, exophytic lesion occupying the free and attached buccal gingiva of the right maxillary lateral incisor and canine. Histopathologically, the tumor showed diffuse and intense polymorphic infiltration by small to medium-sized lymphocytes admixed with numerous eosinophils. The neoplastic cells showed strong and diffuse reactivity for CD2, CD3, CD4, CD10, and PD-1 (programmed cell death 1 [PDCD1]). Rare immunopositivity was seen with BCL6 (B-cell CLL/lymphoma 6) and CXCL13 (chemokine [C-X-C motif] ligand 13). Neoplastic cells were negative for CD7 and EBER ISH (Epstein-Barr virus-encoded small RNA in situ hybridization). CD21 did not show any increased follicular dendritic cell component. Polymerase chain reaction-based assay found monoclonal T-cell receptor γ (TRG) gene rearrangements. Diagnosis of recurrent/residual AITL was rendered. Chemotherapy was administered, with the intraoral tumor resolving completely 3 months later.