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1.
Mol Cancer Res ; 21(4): 345-358, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622795

RESUMO

Cervical cancer is a leading cause of cancer-related deaths in women globally and 99% of cases are caused by persistent infection with high-risk strains of the human papillomavirus (HPV). The HPV oncoproteins E6 and E7 establish the cancer phenotype by cooperating with host proteins and identifying them may have important therapeutic benefits. T-box transcription factor 3 (TBX3) is a critical developmental regulator, and when it is overexpressed postnatally, it contributes to several cancers, but little is known about its expression and role in cervical cancer. The current study shows that TBX3 is upregulated in cervical cancer cell lines as well as precancerous and cervical cancer patient tissue and is associated with larger and more invasive tumors. Knockdown and overexpression cell culture models show that TBX3 promotes HPV-positive cell proliferation, migration, and spheroid growth; however, TBX3 inhibits these processes in HPV-negative cells. Importantly, we show that the tumor promoting activity of TBX3 in cervical cancer is dependent on E6/E7. IMPLICATIONS: In summary, our study highlights the importance of TBX3 as a cooperating partner of E6/E7 in HPV-positive cervical cancer and identifies TBX3 as a potential therapeutic target to treat this neoplasm.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/patologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomavirus Humano , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/patologia , Proliferação de Células , Proteínas com Domínio T/genética
2.
Urol Case Rep ; 42: 102041, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35530544

RESUMO

TFE3-rearranged renal cell carcinoma (RCC) is a rare but well characterised histological subtype of RCC with an aggressive clinical course and propensity for late metastases. Osseous metaplasia is an uncommon but well documented finding in clear cell, papillary and chromophobe RCC. We present the first case of a TFE3-rearranged RCC to be found harbouring metaplastic bone in a 47-year-old woman who presented with a slowly enlarging left flank mass over a 10 year period. This case report adds to the clinicopathological description of TFE3-rearranged RCC and suggests that larger studies are required to fully elucidate the prognosis of these tumours.

3.
Leuk Lymphoma ; 63(2): 370-376, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34612761

RESUMO

The pathogenesis of plasmablastic lymphoma (PBL) involves the Epstein-Barr virus (EBV), human immunodeficiency virus (HIV), and MYC gene aberrations. We aimed to determine the EBV latent infection pattern and frequency of MYC gene aberrations in PBLs. Immunohistochemistry was performed using antibodies for EBNA1, EBNA2, and LMP1 while fluorescence in situ hybridization was performed using a MYC probe. The patient cohort comprised 49 adult cases (44 were HIV-positive and three were HIV-negative). Forty-one cases were EBV-positive with 11 EBNA1-positive cases, all cases EBNA2-negative, and four LMP1-positive cases. Latency 0 was determined in 29 cases, latency I in eight cases, and latency II in four cases. The MYC gene was rearranged in eight cases, showed copy number alterations in 11 cases and, no rearrangement in 11 cases. This is the largest cohort of PBLs from South Africa to show a predominantly restricted EBV latency pattern with MYC gene aberrations as a common finding.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Plasmablástico , Proteínas Proto-Oncogênicas c-myc , Adulto , Antígenos Nucleares do Vírus Epstein-Barr/genética , Genes myc , Herpesvirus Humano 4/genética , Humanos , Hibridização in Situ Fluorescente , Linfoma Plasmablástico/diagnóstico , Linfoma Plasmablástico/genética , Linfoma Plasmablástico/virologia , Proteínas Proto-Oncogênicas c-myc/genética , Latência Viral
4.
Indian J Pathol Microbiol ; 57(2): 209-16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24943752

RESUMO

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are biologically distinctive neoplasms harboring KIT and PDGFRA mutations. Cytokeratin expression in GISTs is an under-recognized diagnostic pitfall, especially in high grade GISTs with limited biopsy material and from metastatic sites. MATERIALS AND METHODS: We evaluated the histomorphology and expression of four 'broad-spectrum' cytokeratin markers, AE1-AE3, CAM 5.2, MNF-116, and 34ßE12 in 64 GISTs diagnosed over a 68-month period. Individual cytokeratins 5, 6, 7, 8, 14, 17, 18, 19, and 20 were investigated in the 'broad-spectrum' cytokeratin-positive GISTs. RESULTS: Of 64 GISTs, 10 (15%) demonstrated cytokeratin immunopositivity. All 10, considered high risk by the National Institutes of Health consensus approach, were immunopositive for CAM 5.2 and MNF-116. Seven were AE1-AE3 immunopositive. Cytokeratins 8 and 18 were confirmed in 10 and 9 GISTs, respectively. One GIST demonstrated biphasic morphology with cytokeratin immunonegativity in low-grade spindle and immunopositivity in high-grade epithelioid foci. KIT and PDGFRA mutational analysis, undertaken in 5/10 cytokeratin-positive GISTs, harbored KIT exon 11 mutations. CONCLUSION: We hypothesize that cytokeratin expression exclusively in high risk GISTs is a consequence of tumor progression. Given the increasing number of commercially available broad-spectrum cytokeratin immunomarkers, including those reacting with cytokeratins 8 and 18, cytokeratin-positive GISTs must be differentiated from carcinomas, melanomas, and a range of cytokeratin-positive sarcomas to ensure optimal patient management and prognostication.


Assuntos
Tumores do Estroma Gastrointestinal/patologia , Expressão Gênica , Queratinas/análise , Adulto , Idoso , Biomarcadores Tumorais/análise , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Int J Surg Pathol ; 22(7): 607-16, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24771257

RESUMO

Plasmablastic lymphoma (PBL) is reported rarely in children. To date, 10 cases are documented in the English-language literature. This study, based on 13 biopsies from 11 HIV-positive children (9 males, 2 females), documents the clinicopathologic features of PBL. The CD4 count ranged from 9 to 800 cells/mm(3). All biopsies demonstrated exclusive plasmablastic morphology; CD20 immunonegativity; and VS38c, EMA, CD31, MUM-1, CD45, and CD79a immunopositivity. B-cell monoclonality was confirmed in all biopsies. Of 3 biopsies subjected to FISH investigation, 2 had a t(8,14) translocation. Nine patients with follow-up details were treated exclusively with HAART (highly active antiretroviral therapy) or with combinations of HAART, chemotherapy, and radiotherapy. Seven patients died. PBL histomorphology, disease stage, and treatment modalities employed were not predictive of outcome. The survival of 2 stage 4 patients for 3 and 8 years each, managed on HAART, chemotherapy, and radiotherapy, however, may justify a role for combined therapeutic modalities for PBL.


Assuntos
Infecções por HIV/complicações , Linfoma Difuso de Grandes Células B/patologia , Adolescente , Terapia Antirretroviral de Alta Atividade , Criança , Pré-Escolar , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/virologia , Masculino
6.
Am J Dermatopathol ; 34(8): 818-21, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23169417

RESUMO

Two infants, 6 months and 4 months of age, presented with bilateral or unilateral external auditory canal polyps and otorrhea, respectively. Additional findings on examination included otitis media and mastoiditis. Tympanic membrane perforation was noted in one patient and a postauricular abscess in the other. Incisional biopsies of the polyps and abscess were reported as nonspecific mixed inflammation and abscess wall, respectively. There was a limited response to an empirical 5-day course of trimethoprim sulfamethoxazole. The children were referred to the academic hospital, and excision of the polyps and biopsies of the middle ear, mastoid, and postauricular abscess was undertaken. All the biopsies demonstrated donovanosis. Reappraisal of the initial incisional biopsies also confirmed donovanosis. Trimethoprim sulfamethoxazole was administered to both patients for 3 weeks, with resolution of the lesions. Subsequent investigations confirmed genital tract donovanosis, human immunodeficiency virus seropositivity, acquired immunodeficiency syndrome, and pulmonary tuberculosis in both mothers. Heightened awareness of the occurrence of donovanosis at unusual sites and improved recognition of the histomorphological features of the disease, especially in small and superficial biopsies, are pivotal not only for its correct diagnosis in extragenital cutaneous and extracutaneous locations but also for timely and adequate therapy and an improved infant and maternal outcome.


Assuntos
Meato Acústico Externo/patologia , Otopatias/patologia , Granuloma Inguinal/patologia , Transmissão Vertical de Doenças Infecciosas , Pólipos/patologia , Anti-Infecciosos/uso terapêutico , Otopatias/tratamento farmacológico , Otopatias/etiologia , Feminino , Granuloma Inguinal/tratamento farmacológico , Granuloma Inguinal/etiologia , Humanos , Lactente , Masculino , Pólipos/tratamento farmacológico , Pólipos/etiologia
7.
Int J Gynecol Pathol ; 31(4): 390-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22653356

RESUMO

Bacillary angiomatosis (BA) is an increasingly reported infection, mainly in patients with acquired immunodeficiency syndrome. Different epidemiological risk factors are associated with the transmission of the causative agents, Bartonella henselae and B. quintana. Vulval BA is described rarely. Two patients presented with a vulval mass (Patient 1) and a verrucous vulval growth (Patient 2), which were diagnosed clinically as tuberculosis and carcinoma, respectively. Patient 1 also had pulmonary tuberculosis and Kaposi sarcoma. Biopsy of the vulval lesions confirmed BA, characterized by a multilobular proliferation of blood vessels that were lined by epithelioid endothelial cells. There were prominent intervascular neutrophils, karyorrhectic debris, and clumps of paravascular argyrophilic organisms. The biopsy from Patient 1 was deep dermal/subcutaneous in location and displayed foci of confluent suppuration. There was florid pseudoepitheliomatous hyperplasia in the biopsy from Patient 2. Molecular investigations confirmed intralesional B. quintana, hitherto unreported in vulval BA, as the causative agent in both biopsies. On follow-up, Patient 2 had developed additional lesions in the vulva and thigh, but all her lesions and the vulval mass (Patient 1) responded to erythromycin treatment. Patient 1 succumbed to tuberculosis. Heightened recognition of BA underpins rapid and optimal clinicopathological diagnosis, even in uncommon locations. Identification of the causative Bartonella species is important for appropriate, interventive social management.


Assuntos
Angiomatose Bacilar/patologia , Bartonella quintana/crescimento & desenvolvimento , Neoplasias Vulvares/microbiologia , Adulto , Angiomatose Bacilar/microbiologia , Bartonella quintana/genética , Biópsia , DNA Bacteriano/química , DNA Bacteriano/genética , Evolução Fatal , Feminino , Histocitoquímica , Humanos , Reação em Cadeia da Polimerase , Neoplasias Vulvares/patologia , Adulto Jovem
8.
BMC Cell Biol ; 12: 18, 2011 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-21569246

RESUMO

BACKGROUND: Cardiac contractility is regulated by dynamic phosphorylation of sarcomeric proteins by kinases such as cAMP-activated protein kinase A (PKA). Efficient phosphorylation requires that PKA be anchored close to its targets by A-kinase anchoring proteins (AKAPs). Cardiac Myosin Binding Protein-C (cMyBPC) and cardiac troponin I (cTNI) are hypertrophic cardiomyopathy (HCM)-causing sarcomeric proteins which regulate contractility in response to PKA phosphorylation. RESULTS: During a yeast 2-hybrid (Y2H) library screen using a trisphosphorylation mimic of the C1-C2 region of cMyBPC, we identified isoform 4 of myomegalin (MMGL) as an interactor of this N-terminal cMyBPC region. As MMGL has previously been shown to interact with phosphodiesterase 4D, we speculated that it may be a PKA-anchoring protein (AKAP).To investigate this possibility, we assessed the ability of MMGL isoform 4 to interact with PKA regulatory subunits R1A and R2A using Y2H-based direct protein-protein interaction assays. Additionally, to further elucidate the function of MMGL, we used it as bait to screen a cardiac cDNA library. Other PKA targets, viz. CARP, COMMD4, ENO1, ENO3 and cTNI were identified as putative interactors, with cTNI being the most frequent interactor.We further assessed and confirmed these interactions by fluorescent 3D-co-localization in differentiated H9C2 cells as well as by in vivo co-immunoprecipitation. We also showed that quantitatively more interaction occurs between MMGL and cTNI under ß-adrenergic stress. Moreover, siRNA-mediated knockdown of MMGL leads to reduction of cMyBPC levels under conditions of adrenergic stress, indicating that MMGL-assisted phosphorylation is requisite for protection of cMyBPC against proteolytic cleavage. CONCLUSIONS: This study ascribes a novel function to MMGL isoform 4: it meets all criteria for classification as an AKAP, and we show that is involved in the phosphorylation of cMyBPC as well as cTNI, hence MMGL is an important regulator of cardiac contractility. This has further implications for understanding the patho-aetiology of HCM-causing mutations in the genes encoding cMyBPC and cTNI, and raises the question of whether MMGL might itself be considered a candidate HCM-causing or modifying factor.


Assuntos
Proteínas de Ancoragem à Quinase A/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/genética , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Receptores Adrenérgicos beta/metabolismo , Troponina I/metabolismo , Técnicas do Sistema de Duplo-Híbrido
9.
J Cutan Pathol ; 37(8): 827-34, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20370850

RESUMO

BACKGROUND: Co-lesional acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma (AIDS-KS) and Mycobacterium tuberculosis-associated granulomatous inflammation are undocumented. METHOD: Retrospective appraisal of skin biopsies with co-lesional AIDS-KS and microscopic tuberculosis (TB). RESULTS: Sixteen biopsies from nine males and seven females form the study cohort. Histological assessment confirmed nodular and plaque KS in 12 and 4 cases each, respectively. Necrotizing, non-necrotizing and a combination of necrotizing and non-necrotizing granulomatous inflammation were present in nine, two and five biopsies each, respectively. The identification of acid fast bacilli on Ziehl-Neelsen staining and M. tuberculosis on polymerase chain reaction confirmed co-lesional TB in 15/16 biopsies. Co-lesional AIDS-KS and lichen scrofulosorum, hitherto undocumented, were confirmed in one biopsy. The histopathological findings served as a marker of human immunodeficiency virus (HIV) infection, visceral TB, therapeutic noncompliance and multidrug resistant pulmonary TB in nine, eight, five and one patient, respectively. M. tuberculosis was cultured from sputum or nodal tissue of all patients. CONCLUSION: Granulomatous inflammation in KS requires optimal histopathological and molecular investigation to confirm an M. tuberculosis origin. The cutaneous co-lesional occurrence of AIDS-KS and microscopic TB may serve as the sentinel clue to HIV infection, systemic TB, therapeutic noncompliance or multidrug resistant TB.


Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Granuloma/microbiologia , Mycobacterium tuberculosis , Sarcoma de Kaposi/microbiologia , Neoplasias Cutâneas/microbiologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/patologia , Adulto , Feminino , Granuloma/complicações , Granuloma/patologia , Humanos , Masculino , Estudos Retrospectivos , Sarcoma de Kaposi/complicações , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/patologia
10.
Pathology ; 38(1): 39-44, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16484007

RESUMO

AIM: This study was undertaken to determine the expression of cell adhesion molecules E-cadherin, cadherin-11, and alpha-, beta- and gamma-catenins in nephroblastomas and to correlate this expression with pathological features and known prognostic factors. METHODS: Immunohistochemistry was performed on 140 cases of nephroblastoma following heat-induced epitope retrieval and using the streptavidin-biotin technique. RESULTS: E-cadherin was expressed in 75 cases (54%), cadherin-11 in 128 cases (91%), alpha-catenin in 93 cases (66%), beta-catenin in 133 cases (95%) and gamma-catenin in 22 cases (16%). Nuclear localisation of beta-catenin was not demonstrated. There was a statistically significant relationship between the administration of preoperative chemotherapy and the expression of E-cadherin, alpha- and gamma-catenin, respectively. These proteins were more frequently expressed in tumours treated with preoperative chemotherapy. Those tumours that expressed all four proteins (E-cadherin, alpha-, beta- and gamma-catenin) showed a statistically significant association with the administration of preoperative chemotherapy, in contrast to tumours that did not express all four proteins. CONCLUSION: Nephroblastomas show a heterogeneous distribution of staining for E-cadherin, cadherin-11, alpha-, beta- and gamma-catenins. Tumours treated with preoperative chemotherapy are more likely to express these molecules. The expression status of E-cadherin, cadherin-11 and the catenins in this cohort does not appear to be of prognostic value.


Assuntos
Caderinas/análise , Cateninas/análise , Neoplasias Renais/química , Neoplasias Renais/patologia , Tumor de Wilms/química , Tumor de Wilms/patologia , Adolescente , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Neoplasias Renais/tratamento farmacológico , Masculino , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Tumor de Wilms/tratamento farmacológico , alfa Catenina/análise , beta Catenina/análise , gama Catenina/análise
11.
Mod Pathol ; 17(1): 89-95, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14631365

RESUMO

Microsatellite instability has been reported in a wide variety of cancer types. Inactivation or loss of tumour suppressor genes has been shown to result in cell cycle deregulation and neoplastic growth. We conducted a microsatellite study using fluorescent-based DNA technology to determine whether mutations in the microsatellite sequences of the deleted in colorectal cancer (DCC) gene, a tumour suppressor at 18q21.1, have any pathologic correlation or prognostic significance in nephroblastomas. Normal and tumour DNA was isolated from 106 cases of nephroblastoma using the standard proteinase K digestion and phenol-chloroform extraction method from paraffin wax-embedded tissue. Polymerase chain reaction using three microsatellite markers; D18S21, D18S34 and D18S58, for the DCC gene were performed. The polymerase chain reaction products were analysed on the ALF Express Automated DNA sequencer. The results were correlated with age at diagnosis, preoperative chemotherapy, clinicopathological stage, histological classification and patient outcome using chi(2) test. Allelic imbalance/loss of heterozygosity appeared to be a more frequent genetic aberration than microsatellite instability with 20% of cases showing allelic imbalance/loss of heterozygosity and only 9% of cases showing microsatellite instability. Genetic aberrations were more frequent in unfavourable histology tumours compared to favourable histology tumours (P=0.012). All patients with genetic aberrations for more than one DCC marker died independent of histological classification and stage (P=0.016). There was no statistically significant difference when DCC aberrations were compared with age at diagnosis, preoperative chemotherapy and clinicopathological stage. In conclusion, this study has found that multiple aberrations involving the DCC locus may play a role in the progression of nephroblastomas, and hence confer a poorer prognosis.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Instabilidade de Microssatélites , Repetições de Microssatélites , Receptores de Superfície Celular/genética , Proteínas Supressoras de Tumor/genética , Tumor de Wilms/genética , Adolescente , Desequilíbrio Alélico , Criança , Pré-Escolar , Receptor DCC , Seguimentos , Humanos , Lactente , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Perda de Heterozigosidade , Mutação , Estadiamento de Neoplasias , Prognóstico , Fatores de Tempo , Resultado do Tratamento , Tumor de Wilms/mortalidade , Tumor de Wilms/patologia , Tumor de Wilms/terapia
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