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1.
Histopathology ; 84(5): 794-809, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38155480

RESUMEN

AIMS: Inflammatory myofibroblastic tumour (IMT) is a rare mesenchymal neoplasm of intermediate malignant potential, occurring at any age and at multiple sites. Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive subtype of IMT, typically involving the abdomen. Most IMTs harbour kinase gene fusions, especially involving ALK and ROS1, but 20-30% of IMTs show no detectable translocations. The aim of this study is to further delineate clinicopathological and molecular characteristics of abdominal IMT and discover potential new therapeutic targets. METHODS AND RESULTS: In 20 IMTs, including four EIMS, RNA fusion analysis was performed, followed by multiplex DNA analysis if no ALK or ROS1 fusion was detected. Fourteen IMTs (70.0%) had an ALK translocation and the fusion partner was identified in 11, including a RRBP1::ALK fusion, not previously described in classical (non-EIMS) IMT. RANBP2::ALK fusion was demonstrated in all EIMS. One IMT had a ROS1 fusion. In all ALK/ROS1 translocation-negative IMTs mutations or fusions - as yet unreported in primary IMT - were found in genes related to the receptor tyrosine kinase (RTK)/PI3K/AKT pathway. Three of four patients with EIMS died of disease [mean survival 8 months (4-15 months)], whereas only one of 14 classical IMT patients succumbed to disease [mean follow-up time 52 months (2-204 months); P < 0.01]. CONCLUSION: This study shows the wide clinical spectrum of abdominal IMTs and affirms the poor prognosis of EIMS, raising discussion about its status as IMT subtype. Furthermore, the newly detected alterations of the RTK/PI3K/AKT pathway expand the molecular landscape of IMTs and provide potential therapeutic targets.


Asunto(s)
Proteínas Tirosina Quinasas , Sarcoma , Humanos , Quinasa de Linfoma Anaplásico/genética , Proteínas Tirosina Quinasas/genética , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Sarcoma/genética
2.
Lancet Oncol ; 23(8): 1087-1096, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35835136

RESUMEN

BACKGROUND: Punch biopsy is the gold standard for diagnosis and subtyping of basal cell carcinoma. The aim of this study was to assess whether use of optical coherence tomography (OCT), a non-invasive imaging tool, might avoid the need for biopsy. METHODS: In a multicentre, randomised, non-inferiority trial, patients (aged ≥18 years) with an indication for biopsy of a suspected basal cell carcinoma outside the H-zone (high-risk zone) of the face were randomly assigned (1:1) to receive either OCT or punch biopsy (regular care) via a web-based randomisation system. Patients were enrolled from three participating centres in the Netherlands: Maastricht University Medical Centre+, Catharina Hospital Eindhoven, and Zuyderland Medical Centre Heerlen. Stratification factors for randomisation were participating centre and the grade of clinical basal cell carcinoma suspicion (high vs low). The primary endpoint was the proportion of patients free from a recurrent or residual lesion (malignant or premalignant) 12 months after treatment. Modified intention-to-treat and per-protocol analyses were conducted, with a predefined non-inferiority margin of -10%. This trial is registered with ClinicalTrials.gov number, NCT03848078, and is complete. FINDINGS: Between Feb 25, 2019, and Sept 2, 2020, 598 patients were enrolled and randomly assigned to either the regular care group (n=299) or the OCT group (n=299). Data on the primary endpoint were available in 553 patients (n=268 in the regular care group, n=285 in the OCT group). After median follow-up of 12·7 months (IQR 11·2-14·1) in the OCT group and 12·6 months (10·8-14·3) in the regular care group, 253 (94%) of 268 patients in the OCT group and 266 (93%) of 285 patients in the regular care group were free from recurrent or residual lesions (malignant or pre-malignant) 12 months after treatment. According to our modified intention-to-treat analysis, the absolute difference (OCT vs regular care) was 1·07% (95% CI -2·93 to 5·06; one-sided p=0·30), with the lower limit of the 95% CI not exceeding the predefined non-inferiority margin of -10%. Per-protocol analyses led to proportions free from a residual or recurrent lesion (premalignant or malignant) of 95% (250 of 263) in the OCT group and 94% (262 of 278) in the regular care group, and an absolute difference of 0·81% (95% CI -2·98 to 4·60; one-sided p=0·34). INTERPRETATION: OCT-guided diagnosis and treatment of basal cell carcinoma is non-inferior to regular care punch biopsy. Implementation of OCT for diagnosis of basal cell carcinoma could reduce the number of consultations and invasive procedures. FUNDING: The Netherlands Organization for Health Research and Development and Maurits en Anna de Kock Stichting.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Adolescente , Adulto , Biopsia , Carcinoma Basocelular/diagnóstico por imagen , Carcinoma Basocelular/terapia , Humanos , Países Bajos , Tomografía de Coherencia Óptica , Resultado del Tratamiento
3.
Histopathology ; 81(3): 329-341, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35758186

RESUMEN

AIMS: Cutaneous metastases of internal malignancies occur in 1-10% of cancer patients. The diagnosis can sometimes be challenging, especially in cases with an unknown primary cancer. MATERIALS AND METHODS: A retrospective case review was performed including all cases of skin metastases from primary internal malignancies diagnosed at the Department of Pathology at the Maastricht University Medical Centre+ from 2007 to 2021. The clinicopathological data were collected and immunohistochemical and molecular diagnostic tests were performed to confirm the primary origin of the metastases. RESULTS: We identified 152 cases (71 female; 31 male patients) of cutaneous metastases of internal malignancies. 28 patients (20 women and 8 men) were diagnosed with multiple cutaneous metastases. Among the female patients, the most common primary tumour was breast cancer (50% of the cases), followed by lung (13.6%), gynaecological (7.3%), and gastrointestinal origin (7.3%). Among the male patients, the most common primary sites were gastrointestinal and lung origin (altogether, 50% of the cases). In 19 patients, the cutaneous metastasis was the first presentation of a clinically silent internal malignancy (18.6%), of which most (78.9%) represented metastatic lung carcinomas. Finally, metastasizing patterns were different across tumour types and gender. CONCLUSION: Breast, lung, gastrointestinal, and gynaecologic cancers are the most common primary tumours demonstrating skin metastases. Infrequently, cutaneous metastases can be the first clinically visual manifestation of an underlying not yet diagnosed internal malignancy; therefore, occasional broad immunohistochemical profiling, molecular clonal analysis, and a continuous high level of awareness are necessary for a precise diagnosis of cutaneous metastases of internal malignancies.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pulmonares , Neoplasias Cutáneas , Neoplasias de la Mama/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Estudios Retrospectivos , Neoplasias Cutáneas/patología
4.
J Am Acad Dermatol ; 83(2): 469-476, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32320773

RESUMEN

PURPOSE: Nodular basal cell carcinoma (nBCC) is mostly treated with surgical excision. Interest in minimally invasive treatment of these low-risk tumors is increasing. We assessed the effectiveness of nBCC treatment with curettage and imiquimod cream compared with surgical excision. METHODS: Patients with nBCC included in this randomized, controlled noninferiority trial were randomly assigned to either a curettage and imiquimod cream group or a surgical excision group. The primary endpoint was the proportion of patients free from treatment failure 1 year after the end of treatment. A prespecified noninferiority margin of 8% was used. A modified intention-to-treat and a per-protocol analysis was performed (ClinicalTrials.gov identifier NCT02242929). RESULTS: One hundred forty-five patients were randomized: 73 to the curettage and imiquimod cream group and 72 to the surgical excision group. The proportion of patients free of recurrence after 12 months was 86.3% (63/73) for the curettage and imiquimod group and 100% (72/72) for the surgical excision group. The difference in efficacy was -13.7% (95% confidence interval -21.6% to -5.8%; 1-sided P = .0004) favoring surgical excision. CONCLUSION: Noninferiority of curettage and imiquimod cream cannot be concluded. Given the still high efficacy of curettage and imiquimod cream and the indolent growth pattern of nBCC, curettage and imiquimod could still be a valuable treatment option with the possibility to prevent overuse of excisions. However, it cannot replace surgical excision.


Asunto(s)
Carcinoma Basocelular/terapia , Legrado , Procedimientos Quirúrgicos Dermatologicos , Imiquimod/administración & dosificación , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Cutáneas/terapia , Piel/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Basocelular/patología , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Crema para la Piel/administración & dosificación , Neoplasias Cutáneas/patología
5.
J Invest Dermatol ; 140(10): 1962-1967, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32147505

RESUMEN

Noninvasive diagnostic strategies such as optical coherence tomography (OCT) enable detailed examination of skin tissue architecture and have potential for identification and subtyping of basal cell carcinoma (BCC). To evaluate the additional diagnostic value of OCT, a prospective cohort study was performed in 182 patients with 250 lesions suspected for non-melanoma skin premalignancies requiring a biopsy. Accuracy of BCC diagnosis and subtype on the basis of clinical examination (CE) of patients was compared with that on the basis of OCT scans in conjunction with clinical images of lesions (cOCT). Confidence levels were recorded on a 5-point scale, where score 0 indicated absence of BCC and scores 1-4 indicated increasing suspicion of BCC. Diagnostic performance parameters were compared using histopathologic diagnosis as gold standard. The patient-based area under the receiver operating characteristic curve (AUC) increased from 85.6% for CE to 91.2% for cOCT (P = 0.061) and the lesion-based AUC from 82.7% to 91.3% (P < 0.001). When confidence scores 1-4 were defined as positive, patient-based specificity increased from 47.5% (CE alone) to 76.8% (cOCT) at similar sensitivity (97.6% and 95.2%, respectively). cOCT slightly improved the ability to discriminate between superficial and nonsuperficial BCC subtypes and seemed to be a valuable addition to CE alone in the diagnosis and subtyping of BCC.


Asunto(s)
Carcinoma Basocelular/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad
6.
Oncotarget ; 8(3): 3870-3880, 2017 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-27965472

RESUMEN

Biomarkers predicting treatment response to the monoclonal antibody cetuximab in locally advanced head and neck squamous cell carcinomas (LAHNSCC) are lacking. We hypothesize that tumor accessibility is an important factor in treatment success of the EGFR targeting drug. We quantified uptake of cetuximab labeled with Zirconium-89 (89Zr) using PET/CT imaging.Seventeen patients with stage III-IV LAHNSCC received a loading dose unlabeled cetuximab, followed by 10 mg 54.5±9.6 MBq 89Zr-cetuximab. PET/CT images were acquired either 3 and 6 or 4 and 7 days post-injection. 89Zr-cetuximab uptake was quantified using standardized uptake value (SUV) and tumor-to-background ratio (TBR), and correlated to EGFR immunohistochemistry. TBR was compared between scan days to determine optimal timing.Uptake of 89Zr-cetuximab varied between patients (day 6-7: SUVpeak range 2.5-6.2). TBR increased significantly (49±28%, p < 0.01) between first (1.1±0.3) and second scan (1.7±0.6). Between groups with a low and high EGFR expression a significant difference in SUVmean (2.1 versus 3.0) and SUVpeak (3.2 versus 4.7) was found, however, not in TBR. Data is available at www.cancerdata.org (DOI: 10.17195/candat.2016.11.1).In conclusion, 89Zr-cetuximab PET imaging shows large inter-patient variety in LAHNSCC and provides additional information over FDG-PET and EGFR expression. Validation of the predictive value is recommended with scans acquired 6-7 days post-injection.


Asunto(s)
Antineoplásicos Inmunológicos/administración & dosificación , Cetuximab/farmacocinética , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radioisótopos/química , Circonio/química , Anciano , Antineoplásicos Inmunológicos/química , Cetuximab/administración & dosificación , Cetuximab/química , Receptores ErbB/metabolismo , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Imagen Molecular , Estadificación de Neoplasias , Resultado del Tratamiento
7.
J Am Acad Dermatol ; 75(1): 126-34, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27067393

RESUMEN

BACKGROUND: Nonsteroidal anti-inflammatory drugs and vitamin-D derivatives can target signaling pathways activated in basal cell carcinoma (BCC). OBJECTIVE: We investigated the efficacy of topically applied diclofenac sodium 3% gel, calcitriol 3 µg/g ointment, and a combination of both in superficial BCC (sBCC) and nodular BCC. METHODS: Patients with a primary, histologically proven sBCC (n = 64) or nodular BCC (n = 64) were randomized to topical diclofenac, calcitriol, combination of both, or no topical treatment (control group). After self-application twice daily under occlusion (8 weeks), tumors were excised. Primary outcome was posttreatment expression levels of proliferation (Ki-67) and antiapoptosis (B-cell lymphoma [Bcl-2]) immunohistochemical markers. Secondary outcomes were histologic clearance, adverse events, application-site reactions, and patient compliance. RESULTS: sBCC treated with diclofenac showed a significant decrease in Ki-67 (P < .001) and Bcl-2 (P = .001), and after combination therapy for Ki-67 (P = .012). Complete histologic tumor regression was seen in 64.3% (P = .0003) of sBCC (diclofenac) and 43.8% (P = .007) of sBCC (combination therapy) compared with 0.0% of controls. No significant changes were found in nodular BCC. Application-site reactions were mostly mild to moderate. LIMITATIONS: The sample size was small. CONCLUSION: Our results suggest that topical diclofenac is a promising new treatment for sBCC. Its mode of action differs from available noninvasive therapies, and thus has an additive value.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Calcitriol/uso terapéutico , Carcinoma Basocelular/tratamiento farmacológico , Diclofenaco/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Vitaminas/uso terapéutico , Administración Tópica , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Apoptosis/efectos de los fármacos , Calcitriol/administración & dosificación , Calcitriol/efectos adversos , Carcinoma Basocelular/química , Carcinoma Basocelular/patología , Proliferación Celular/efectos de los fármacos , Diclofenaco/administración & dosificación , Diclofenaco/efectos adversos , Quimioterapia Combinada , Femenino , Geles , Humanos , Antígeno Ki-67/análisis , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Pomadas , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Método Simple Ciego , Neoplasias Cutáneas/química , Neoplasias Cutáneas/patología , Resultado del Tratamiento , Vitaminas/administración & dosificación , Vitaminas/efectos adversos
9.
J Am Acad Dermatol ; 73(1): 93-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25935596

RESUMEN

BACKGROUND: Noninvasive treatments are frequently used in treatment of superficial basal cell carcinoma (sBCC) because of better cosmetic results, lower costs, and less burden on health care services when compared with surgical excision. However, probability of treatment failure is higher after noninvasive therapies and may depend on histologic tumor characteristics. OBJECTIVE: We sought to investigate whether tumor thickness and adnexal extension are determinants of treatment failure in sBCC treated with topical methylaminolevulinate-photodynamic therapy, imiquimod, or 5-fluorouracil. METHODS: Data were derived from a randomized controlled trial on the effectiveness of methylaminolevulinate photodynamic therapy, imiquimod, and 5-fluorouracil for treatment of sBCC (ISRCTN79701845). For tumors with treatment failure (n = 112) and a randomly selected control group of tumors without treatment failure (n = 224) data on tumor thickness and adnexal extension were retrospectively collected. Treatment failure was defined as a clinically and histologically persistent or recurrent tumor within 1-year posttreatment. RESULTS: Tumor thickness of included patients ranged from 0.2 to 1.0 mm. Tumor thickness and adnexal extension of sBCC were not significantly associated with treatment failure of methylaminolevulinate photodynamic therapy, imiquimod, or 5-fluorouracil. LIMITATIONS: Follow-up period of 1 year is a limitation. CONCLUSION: There seems to be no need to determine tumor thickness or adnexal extension in sBCC before treatment.


Asunto(s)
Ácido Aminolevulínico/uso terapéutico , Aminoquinolinas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/patología , Fluorouracilo/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imiquimod , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Insuficiencia del Tratamiento
11.
Medicine (Baltimore) ; 93(28): e285, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25526463

RESUMEN

Treatment of BRAFV600E-mutant melanoma by small molecule inhibitors that target BRAFV600E or MEK kinases is increasingly used in clinical practice and significantly improve patient outcome. However, patients eventually become resistant and therapeutic improvement is required. Molecular diversity within individual tumors (intratumor heterogeneity) and between tumors within a single patient (intrapatient heterogeneity) poses a significant challenge to precision medicine. Using immunohistochemistry, we determined the extent of BRAFV600E intratumor and intrapatient heterogeneity and the influence of morphological heterogeneity in a large series of 171 melanomas of 81 patients. The BRAFV600E mutation rate found in our melanoma series is 44%, with none of 22 (0%) melanoma in situ, 23 of 56 (41%) primary tumors, 28 of 59 (48%) regional metastases, and 24 of 34 (71%) distant metastases harboring the mutation. In general, a diffuse homogeneous immunostaining was seen, even in tumors consisting of more than one cell type, that is, epithelioid, spindle, and/or small cell types. Nevertheless, BRAFV600E-mutant melanomas more often had a purely epithelioid cell population (P=0.063), that is more evident among distant metastases (P=0.014). Only two of 75 (3%) mutated specimens (one primary and one metastasis) displayed heterogeneous BRAFV600E expression. The primary tumor was also morphologically heterogeneous and exclusively displayed BRAFV600E in the epithelioid component, confirming an association between BRAFV600E and epithelioid cells. Twenty-eight of 30 patients (93%) had concordant BRAFV600E mutation status between their tumors. Taken together, BRAFV600E intratumor and intrapatient heterogeneity in melanoma is diminutive, nevertheless, the identified exceptions will have important implications for the clinical management of this disease.


Asunto(s)
ADN de Neoplasias/genética , Células Epitelioides/metabolismo , Melanoma/genética , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis Mutacional de ADN , Células Epitelioides/inmunología , Células Epitelioides/patología , Femenino , Heterogeneidad Genética , Humanos , Inmunohistoquímica , Masculino , Melanoma/metabolismo , Melanoma/patología , Persona de Mediana Edad , Proteínas Proto-Oncogénicas B-raf/inmunología , Proteínas Proto-Oncogénicas B-raf/metabolismo , Estudios Retrospectivos , Neoplasias Cutáneas , Adulto Joven , Melanoma Cutáneo Maligno
12.
PLoS One ; 9(9): e106427, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25181405

RESUMEN

BACKGROUND: Basal cell carcinoma (BCC) is the most common cancer in Caucasians. Trichoepithelioma (TE) is a benign neoplasm that strongly resembles BCC. Both are hair follicle (HF) tumours. HFs are hypoxic microenvironments, therefore we hypothesized that hypoxia-induced signalling pathways could be involved in BCC and TE as they are in other human malignancies. Hypoxia-inducible factor 1 (HIF1) and mechanistic/mammalian target of rapamycin (mTOR) are key players in these pathways. OBJECTIVES: To determine whether HIF1/mTOR signalling is involved in BCC and TE. METHODS: We used immunohistochemical staining of formalin-fixed paraffin-embedded BCC (n = 45) and TE (n = 35) samples to assess activity of HIF1, mTORC1 and their most important target genes. The percentage positive tumour cells was assessed manually in a semi-quantitative manner and categorized (0%, <30%, 30-80% and >80%). RESULTS: Among 45 BCC and 35 TE examined, expression levels were respectively 81% and 57% (BNIP3), 73% and 75% (CAIX), 79% and 86% (GLUT1), 50% and 19% (HIF1α), 89% and 88% (pAKT), 55% and 61% (pS6), 15% and 25% (pMTOR), 44% and 63% (PHD2) and 44% and 49% (VEGF-A). CAIX, Glut1 and PHD2 expression levels were significantly higher in TE when only samples with at least 80% expression were included. CONCLUSIONS: HIF and mTORC1 signalling seems active in both BCC and TE. There are no appreciable differences between the two with respect to pathway activity. At this moment immunohistochemical analyses of HIF, mTORC1 and their target genes does not provide a reliable diagnostic tool for the discrimination of BCC and TE.


Asunto(s)
Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Transducción de Señal , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Serina-Treonina Quinasas TOR/metabolismo , Anciano , Hipoxia de la Célula , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/metabolismo , Síndromes Neoplásicos Hereditarios/patología , Fosforilación , Transducción de Señal/genética , Coloración y Etiquetado , Estadísticas no Paramétricas
14.
Biochim Biophys Acta ; 1826(1): 89-102, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22503822

RESUMEN

Cutaneous malignant melanoma (CMM) is the most life-threatening neoplasm of the skin and is considered a major health problem as both incidence and mortality rates continue to rise. Once CMM has metastasized it becomes therapy-resistant and is an inevitably deadly disease. Understanding the molecular mechanisms that are involved in the initiation and progression of CMM is crucial for overcoming the commonly observed drug resistance as well as developing novel targeted treatment strategies. This molecular knowledge may further lead to the identification of clinically relevant biomarkers for early CMM detection, risk stratification, or prediction of response to therapy, altogether improving the clinical management of this disease. In this review we summarize the currently identified genetic and epigenetic alterations in CMM development. Although the genetic components underlying CMM are clearly emerging, a complete picture of the epigenetic alterations on DNA (DNA methylation), RNA (non-coding RNAs), and protein level (histone modifications, Polycomb group proteins, and chromatin remodeling) and the combinatorial interactions between these events is lacking. More detailed knowledge, however, is accumulating for genetic and epigenetic interactions in the aberrant regulation of the INK4b-ARF-INK4a and microphthalmia-associated transcription factor (MITF) loci. Importantly, we point out that it is this interplay of genetics and epigenetics that effectively leads to distorted gene expression patterns in CMM.


Asunto(s)
Melanoma/genética , Neoplasias Cutáneas/genética , Ensamble y Desensamble de Cromatina , Metilación de ADN , Epigénesis Genética , Expresión Génica , Humanos , MicroARNs/genética
15.
PLoS One ; 7(12): e51710, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23284750

RESUMEN

BACKGROUND: The genetic background of Basal Cell Carcinoma (BCC) has been studied extensively, while its epigenetic makeup has received comparatively little attention. Epigenetic alterations such as promoter hypermethylation silence tumor suppressor genes (TSG) in several malignancies. OBJECTIVE: We sought to analyze the promoter methylation status of ten putative (tumor suppressor) genes that are associated with Sonic Hedgehog (SHH), WNT signaling and (hair follicle) tumors in a large series of 112 BCC and 124 healthy control samples by methylation-specific PCR. RESULTS: Gene promoters of SHH (P = 0.016), adenomatous polyposis coli (APC) (P = 0.003), secreted frizzled-related protein 5 (SFRP5) (P = 0.004) and Ras association domain family 1A (RASSF1A) (P = 0.023) showed significantly more methylation in BCC versus normal skin. mRNA levels of these four genes were reduced for APC and SFRP5 in BCC (n = 6) vs normal skin (n = 6). Down regulation of SHH, APC and RASSF1A could be confirmed on protein level as well (P<0.001 for all genes) by immunohistochemical staining. Increased canonical WNT activity was visualized by ß-catenin staining, showing nuclear ß-catenin in only 28/101 (27.7%) of BCC. Absence of nuclear ß-catenin in some samples may be due to high levels of membranous E-cadherin (in 94.1% of the samples). CONCLUSIONS: We provide evidence that promoter hypermethylation of key players within the SHH and WNT pathways is frequent in BCC, consistent with their known constitutive activation in BCC. Epigenetic gene silencing putatively contributes to BCC tumorigenesis, indicating new venues for treatment.


Asunto(s)
Carcinoma Basocelular/genética , Metilación de ADN , Epigénesis Genética , Proteínas Hedgehog/genética , Neoplasias Cutáneas/genética , Piel/metabolismo , Proteínas Wnt/genética , Anciano , Estudios de Casos y Controles , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Regiones Promotoras Genéticas/genética , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/genética
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