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1.
Head Neck Pathol ; 17(1): 265-274, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36303014

RESUMO

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare translocation-related soft tissue sarcoma, occurring mainly in the limbs and trunk in young adults and adolescents. ASPS is rarely seen in the head and neck and one fourth of those cases described are tongue primary. Given its nonspecific symptoms, clinical findings, and rarity in this location, lingual ASPS (L-ASPS) has been reported to be commonly misdiagnosed as various benign tumors, leading to adverse outcomes. METHODS: We report a case of L-ASPS occurring in the oldest (78 years) female patient published to date and comprehensively review the literature from 1952 to 2022. RESULTS: She presented with a slow-growing (2-year duration) tongue mass, measuring 3.5 cm on palpation. Intraoperative frozen section could not render the definitive diagnosis. The pathological findings of the tumor were characteristic of ASPS with eosinophilic polygonal cells in an organoid/nested pattern, rich sinusoidal capillaries, and TFE3 immunoreactivity, except for the strong diffuse aberrant cytoplasmic CD68 immunoexpression and absence of intracytoplasmic crystalline inclusions on PAS with diastase. After TFE3 gene rearrangement had been identified with fluorescent in-situ hybridization, reflex testing confirmed a rearrangement of TFE3 gene with the known fusion partner ASPSCR1. CONCLUSIONS: ASPS should be included in the differential diagnoses in cases of any slow-growing lingual masses (especially vascular ones) with non-specific clinical pictures, regardless of the patient's age.


Assuntos
Sarcoma Alveolar de Partes Moles , Neoplasias de Tecidos Moles , Neoplasias da Língua , Adolescente , Adulto Jovem , Humanos , Feminino , Idoso , Sarcoma Alveolar de Partes Moles/diagnóstico , Fatores de Transcrição , Neoplasias de Tecidos Moles/patologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética
2.
J Neurosurg Case Lessons ; 3(8)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130545

RESUMO

BACKGROUND: The authors reported the first pediatric case of a craniocerebral gunshot injury successfully treated with a wound vacuum-assisted closure (VAC) device after dehiscence and infection of the initial cranial wound. OBSERVATIONS: A 17-year-old boy suffered several gunshots to the left hemisphere, resulting in significant damage to the scalp, calvaria, and brain. Emergency hemicraniectomy was performed, with reconstruction of a complicated scalp wound performed at the initial surgery. The scalp was devitalized and ultimately dehisced, resulting in a cranial infection. It was treated first with a repeated attempt at primary closure, which failed because of persistent devitalized tissue, and was then treated with aggressive debridement followed by placement of a wound VAC device over the exposed brain as a bridge therapy to reconstruction. This procedure was deemed necessary given the active infection. LESSONS: The patient received delayed reconstruction with a free split-thickness skin graft and made a remarkable recovery, with cranioplasty performed 6 months later. The authors reviewed the literature on wound VAC use in cranial wound treatment and proposed it as a legitimate bridge therapy to definitive reconstruction in the setting of dirty wounds, active infection, or even hemodynamically unstable patients.

3.
Pathophysiology ; 28(3): 437-456, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35366284

RESUMO

Hydrogen sulfide (H2S) is a gasotransmitter that exerts a multitude of functions in both physiologic and pathophysiologic processes. H2S-synthesizing enzymes are increased in a variety of human malignancies, including colon, prostate, breast, renal, urothelial, ovarian, oral squamous cell, and thyroid cancers. In cancer, H2S promotes tumor growth, cellular and mitochondrial bioenergetics, migration, invasion, angiogenesis, tumor blood flow, metastasis, epithelia-mesenchymal transition, DNA repair, protein sulfhydration, and chemotherapy resistance Additionally, in some malignancies, increased H2S-synthesizing enzyme expression correlates with a worse prognosis and a higher tumor stage. Here we review the role of H2S in cancer, with an emphasis on the molecular mechanisms by which H2S promotes cancer development, progression, dedifferentiation, and metastasis.

4.
Redox Biol ; 38: 101675, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33202302

RESUMO

Recent evidence has revealed that exposing cells to exogenous H 2 S or inhibiting cellular H 2 S synthesis can modulate cell cycle checkpoints, DNA damage and repair, and the expression of proteins involved in the maintenance of genomic stability, all suggesting that H 2 S plays an important role in the DNA damage response (DDR). Here we review the role of H 2 S in the DRR and maintenance of genomic stability. Treatment of various cell types with pharmacologic H 2 S donors or cellular H 2 S synthesis inhibitors modulate the G 1 checkpoint, inhibition of DNA synthesis, and cause p21, and p53 induction. Moreover, in some cell models H 2 S exposure induces PARP-1 and g-H2AX foci formation, increases PCNA, CHK2, Ku70, Ku80, and DNA polymerase-d protein expression, and maintains mitochondrial genomic stability. Our group has also revealed that H 2 S bioavailability and the ATR kinase regulate each other with ATR inhibition lowering cellular H 2 S concentrations, whereas intracellular H 2 S concentrations regulate ATR kinase activity via ATR serine 435 phosphorylation. In summary, these findings have many implications for the DDR, for cancer chemotherapy, and fundamental biochemical metabolic pathways involving H 2 S.


Assuntos
Reparo do DNA , Sulfeto de Hidrogênio , Animais , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Humanos , Fosforilação
5.
Anticancer Res ; 39(4): 1761-1765, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952715

RESUMO

BACKGROUND/AIM: Primary bone neoplasms include osteosarcomas (OS), chondrosarcomas (CS), and giant cell tumors (GCT). Nicotinamide phosphoribosyl transferase (NAMPT) catalyzes the rate-limiting step of nicotinamide adenine dinucleotide synthesis and is increased in multiple tumor types. In malignancies, NAMPT expression often correlates positively with tumor grade, chemotherapy resistance, and metastatic potential. MATERIALS AND METHODS: Tissue microarray was used to examine NAMPT expression in benign bone and cartilage, GCTs, OS, and different CS grades. RESULTS: For the first time, we showed that NAMPT expression was increased in GCTs and OS compared to benign bone, and in CS compared to benign cartilage. Its expression also increased with higher CS grade. CONCLUSION: Our data indicate that NAMPT plays a role in bone sarcomas and GCTs, and its higher expression may contribute to increased tumor aggressiveness.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Ósseas/enzimologia , Osso e Ossos/enzimologia , Cartilagem/enzimologia , Condrossarcoma/enzimologia , Citocinas/análise , Nicotinamida Fosforribosiltransferase/análise , Osteossarcoma/enzimologia , Neoplasias Ósseas/patologia , Osso e Ossos/patologia , Cartilagem/patologia , Condrossarcoma/patologia , Tumor de Células Gigantes do Osso/enzimologia , Tumor de Células Gigantes do Osso/patologia , Humanos , Imuno-Histoquímica , Gradação de Tumores , Osteossarcoma/patologia , Análise Serial de Tecidos , Regulação para Cima
7.
DNA Repair (Amst) ; 73: 55-63, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30470507

RESUMO

The ataxia telangiectasia-mutated and Rad3-related (ATR) serine/threonine kinase plays a central role in the repair of replication-associated DNA damage, the maintenance of S and G2/M-phase genomic stability, and the promotion of faithful mitotic chromosomal segregation. A number of stimuli activate ATR, including persistent single-stranded DNA at stalled replication folks, R loop formation, hypoxia, ultraviolet light, and oxidative stress, leading to ATR-mediated protein phosphorylation. Recently, hydrogen sulfide (H2S), an endogenous gasotransmitter, has been found to regulate multiple cellular processes through complex redox reactions under similar cell stress environments. Three enzymes synthesize H2S: cystathionine-ß-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate sulfurtransferase. Since H2S can under some conditions cause DNA damage, we hypothesized that ATR activity may regulate cellular H2S concentrations and H2S-syntheszing enzymes. Here we show that human colorectal cancer cells carrying biallelic knock-in hypomorphic ATR mutations have lower cellular H2S concentrations than do syngeneic ATR wild-type cells, and all three H2S-synthesizing enzymes show lower protein expression in the ATR hypomorphic mutant cells. Additionally, ATR serine 428 phosphorylation is altered by H2S donor and H2S synthesis enzyme inhibition, while the oxidative-stress induced phosphorylation of the ATR-regulated protein CHK1 on serine 345 is increased by H2S synthesis enzyme inhibition. Lastly, inhibition of H2S production potentiated oxidative stress-induced double-stranded DNA breaks in the ATR hypomorphic mutant compared to ATR wild-type cells. Our findings demonstrate that the ATR kinase regulates and is regulated by H2S.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sulfeto de Hidrogênio/metabolismo , Linhagem Celular Tumoral , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/genética , Cistationina gama-Liase/metabolismo , Quebras de DNA de Cadeia Dupla , Regulação da Expressão Gênica , Humanos , Mutação , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sulfurtransferases/genética , Sulfurtransferases/metabolismo
8.
Oral Maxillofac Surg Clin North Am ; 31(1): 39-68, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30449526

RESUMO

Soft tissue reconstruction of head and neck ablative defects is a broad, challenging, and subjective topic. The authors outline goals to keep in mind when deciding on a primary reconstructive option for defects created by oncologic resection. Factors considered in local, regional, and distant flap selection are discussed. Based on the goals of reconstruction and factors involved in flap selection, a defect-based reconstructive algorithm is developed to help choose the ideal reconstructive option. The authors also discuss indications, pearls, pitfalls, and challenges in the harvest and inset of commonly used soft tissue flaps for head and neck reconstructive surgery.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Algoritmos , Estética , Retalhos de Tecido Biológico , Humanos , Qualidade de Vida
9.
Anticancer Res ; 38(11): 6085-6090, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30396922

RESUMO

BACKGROUND: Cystathione ß-synthase (CBS) catalyzes the conversion of homocysteine and cysteine to hydrogen sulfide (H2S) and cystathione, via the trans-sulfuration pathway. CBS protein expression levels are increased in several different human malignancies, with increased protein expression correlating with parameters such as tumor stage, anaplasia, metastases, and chemotherapy resistance. MATERIALS AND METHODS: This study employed tissue microarrays to examine CBS expression in benign thyroid tissue, thyroid oncocytomas, thyroid follicular adenomas, and in follicular, papillary, anaplastic, and medullary thyroid carcinomas. RESULTS: CBS expression was increased in all thyroid carcinomas types compared to benign thyroid tissue, but not in thyroid follicular adenomas or oncocytomas. A similar pattern was observed for nicotinamide phosphoribosyltransferase (NAMPT) tissue microarray analysis comparing thyroid adenomas and follicular carcinomas. CONCLUSION: For the first time, we showed that an H2S-syntheszing enzyme plays a role in thyroid malignancies. Additionally, our data suggest that CBS and NAMPT immunohistochemistry may be useful in differentiating follicular adenomas from follicular carcinomas.


Assuntos
Cistationina beta-Sintase/biossíntese , Neoplasias da Glândula Tireoide/enzimologia , Adenocarcinoma Folicular/enzimologia , Adenoma Oxífilo/enzimologia , Carcinoma Neuroendócrino/enzimologia , Citocinas/biossíntese , Humanos , Sulfeto de Hidrogênio/metabolismo , Imuno-Histoquímica , Nicotinamida Fosforribosiltransferase/biossíntese , Câncer Papilífero da Tireoide/enzimologia , Carcinoma Anaplásico da Tireoide/enzimologia , Análise Serial de Tecidos
10.
Case Rep Oncol ; 11(3): 682-687, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30483098

RESUMO

Mucoepidermoid carcinoma (MEC) is the most common malignant epithelial neoplasm of the salivary glands. MECs of the mouth floor are rare, with only a few cases reported. Here we report a MEC of the mouth floor in a 55-year-old woman. Since several studies have shown that hydrogen sulfide (H2S)-synthesizing enzymes are often increased in malignant tumors compared to benign counterpart tissues, we used western blotting to compare the protein levels of cystathionine-ß-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3-MST) in a mouth floor MEC to adjacent benign oral mucosae. We also used high-performance liquid chromatography to quantify possible differences in tissue sulfur fraction concentrations between the two biopsy types. Last, we used western blotting to examine nicotinamide phosphoribosyl transferase (Nampt), mitoNEET, and phospho-ser727-Stat3 levels in the biopsies. We found that all the proteins and phospho-ser727-Stat3 are increased in the MEC compared to benign mucosae. Interestingly, free H2S levels, acid-labile, and the sulfane sulfur factions were essentially the same between the MEC and benign tissue. Although limited to a single and unusual tumor type, to our knowledge this is only the third time H2S concentrations were directly quantified inside a human tumor. Last, our results replicate those of two previous studies where the H2S-synthesizing enzymes are increased in a malignant tumor, while free H2S is either not increased or only slightly increased, suggesting that malignant tumors rapidly metabolize H2S as part of tumor maintenance and growth.

11.
Case Rep Oncol ; 11(2): 585-590, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30283315

RESUMO

Adenoid cystic carcinomas (ACC) constitute 1% of all head and neck malignancies and are very rare in the oral cavity. With < 60 oral ACCs described, their pathobiology is incompletely understood. Here, we report a case of oral cavity ACC in a 54-year-old woman. Since recent studies have demonstrated that several human tumors overexpress the hydrogen sulfide (H2S)-synthesizing enzymes cystathionine-ß-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3-MST), and also show dysregulated H2S levels, we examined these biomarkers in the oral ACC and compared the results to those of adjacent benign oral epithelium. Western blotting was used to compare the protein expression of CBS, CSE, 3-MST, nicotinamide phosphoribosyl transferase, and mitoNEET in ACC and adjacent benign oral mucosae. High-performance liquid chromatography was used to quantify the differences in tissue H2S concentrations between the two biopsy types. We found that all the proteins examined here were increased in the ACC compared to adjacent benign oral mucosae. Interestingly, H2S concentrations were decreased approximately 30% in ACC compared to benign mucosae. Thus, in one example of this rare tumor type, the enzymes that synthesize H2S are increased, while tissue H2S levels are lower than those found in adjacent benign oral mucosae. Although limited to a single rare tumor type, to our knowledge this is the second time H2S concentrations have been directly quantified inside a human tumor. Last, our results may indicate that alterations in H2S synthesis and metabolism may be important in the pathobiology of ACC.

12.
Anticancer Res ; 38(7): 3843-3852, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29970504

RESUMO

BACKGROUND/AIM: Hydrogen sulfide (H2S) and the enzymes that synthesize it, cystathionine-b-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate, are increased in different human malignancies. Due to its short half-life, H2S concentrations have not been directly measured in a human malignancy. Here we directly measured in vivo H2S levels within oral squamous cell carcinoma (OSCC). PATIENTS AND METHODS: Punch biopsies of OSCC and benign mucosae from 15 patients were analyzed by HPLC, western blotting, and tissue microarray analyses. RESULTS: H2S concentrations were significantly higher in OSCC compared to adjacent benign oral mucosae. Western blot and tissue microarray studies revealed significantly increased cystathionine-b-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate, phopho-Stat3, mitoNEET, hTERT, and MAPK protein levels in OSCC. CONCLUSION: H2S concentrations and the enzymes that synthesize it are significantly increased in OSCC. Here, for the first time H2S concentrations within a living human malignancy were measured and compared to adjacent counterpart benign tissue.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Sulfeto de Hidrogênio/metabolismo , Mucosa Bucal/metabolismo , Neoplasias Bucais/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Cromatografia Líquida de Alta Pressão , Humanos , Pessoa de Meia-Idade , Análise Serial de Tecidos
13.
J Oral Maxillofac Surg ; 76(1): 140-145, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28941376

RESUMO

PURPOSE: We present a series of cases of mandibular symphysis fractures treated at our institution with a 3-dimensional strut plate. The aim of the present study was to confirm the stability of this fixation technique and discuss its advantages, disadvantages, and potential complications. PATIENTS AND METHODS: We designed and implemented a retrospective cohort study of patients who underwent surgery by the same surgeon at our institution from July 2012 to April 2014 for a mandible fracture with a symphysis component. The patients were evaluated to identify aspects of occlusion, fracture mobility, postoperative infection, and the need for hardware removal. RESULTS: The sample included 12 subjects who had met the inclusion criteria. The inclusion criteria were a linear noncomminuted fracture, sufficient distance from the mental foramina, a maximum of 5 days between the trauma and surgery, and a minimum postoperative period of 3 months. The mean age of the sample was 33.4 years, and 1 of the 12 patients (8.3%) was female. Of the 12 patients, 10 did well, and 2 developed a surgical site infection, 1 of whom also experienced nonunion and required additional fixation. CONCLUSIONS: The results of the present study suggest a 3-dimensional strut plate applied to symphysis fractures provides adequate fracture stabilization with a risk of complications comparable to that of more traditional fixation methods. In addition, the technique has the added advantage of minimal manipulation and adaptation, which could shorten the overall operating time.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas Mandibulares/cirurgia , Adulto , Humanos , Fraturas Mandibulares/diagnóstico por imagem , Complicações Pós-Operatórias , Desenho de Prótese , Radiografia Panorâmica , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
14.
Craniomaxillofac Trauma Reconstr ; 10(4): 318-322, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29109844

RESUMO

This report establishes a novel application of a commercially available porcine urinary bladder extracellular matrix, MatriStem (ACell, Inc., Columbia, MD), in the salvage of partial loss of the skin paddle of a fibula osteoseptocutaneous free flap that was utilized for mandibular reconstruction.

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