RESUMEN
Expression of the non-coding RNA XIST is essential for initiating X chromosome inactivation (XCI) during early development in female mammals. As the main function of XCI is to enable dosage compensation of chromosome X genes between the sexes, XCI and XIST expression are generally absent in male normal tissues, except in germ cells and in individuals with supernumerary X chromosomes. Via a systematic analysis of public sequencing data of both cancerous and normal tissues, we report that XIST is somatically activated in a subset of male human cancers across diverse lineages. Some of these cancers display hallmarks of XCI, including silencing of gene expression, reduced chromatin accessibility, and increased DNA methylation across chromosome X, suggesting that the developmentally restricted, female-specific program of XCI can be somatically accessed in male cancers.
Asunto(s)
Neoplasias , ARN Largo no Codificante , Animales , Humanos , Masculino , Femenino , Inactivación del Cromosoma X/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Cromosoma X/metabolismo , Compensación de Dosificación (Genética) , Mamíferos/genética , Neoplasias/genéticaRESUMEN
BACKGROUND/AIM: The aim of the study was to identify predictors of long-term survival and propose an improved risk stratification in patients with pulmonary germ-cell metastases admitted for pulmonary metastasectomy. PATIENTS AND METHODS: Thirty-four patients admitted to the Division of Thoracic Surgery Munich, Germany, from 04/1994 until 09/2017 were retrospectively analyzed. The impact of clinical parameters on survival was calculated using Kaplan-Meier, multivariate Cox regression analysis and receiver-operator curves. RESULTS: Ten-year overall survival was 75.3%. Elevated American Society of Anesthesiologists score, metachronous metastasis, embryonal histology, intrathoracic lymph node involvement, brain metastases and thoracic wall infiltration were significant predictors of reduced survival. With the independent predictors (embryonal histology, metachronous metastasis and thoracic wall infiltration), a germinal non-seminomatous lung metastasis risk of death score (GLUMER) was calculated, accurately predicting survival (area under curve=0.8839, p=0.0023). CONCLUSION: In patients with pulmonary germ-cell metastases, intrathoracic lymph node involvement, embryonal carcinoma, metachronous metastasis and thoracic wall infiltration represent negative predictors of long-term survival. The GLUMER score might represent a promising tool for use in adapted follow-up care in high-risk patients.
Asunto(s)
Neoplasias Pulmonares , Metastasectomía , Neoplasias de Células Germinales y Embrionarias , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Ganglios Linfáticos/patología , Neoplasias de Células Germinales y Embrionarias/cirugía , Neumonectomía , Pronóstico , Estudios RetrospectivosRESUMEN
Activation of the receptor for epidermal growth factor (EGFR) in some testicular tumors activates several signaling pathways. Some components of these pathways are phosphorylated or mutated in testicular germ tumors (TCGT), including EGFR, Kirstein ras oncogen (KRAS) and cell surface protein of the germ cell (KIT). The latter two activate RAF /MEK/ERK and PI3 K/AKT, and interconnect with the EGFR/pI3 k/Akt pathway. We investigated the expression of EGFR/pI3 k/Akt pathway proteins in seminomas and in their precursor lesion, germinal cell neoplasia in situ (GCNIS) and related genetic mutations. We used immunohistochemistry for pEGFR, pI3 k and pAkt expression with a scoring system for 46 seminoma surgical specimens: 36 classical and 10 GCNIS. In 17 samples, the mutations of EGFR (exons 19 - 21), KIT (exons 11, 17) and KRAS (exons 2, 3) were investigated using qPCR and sequencing. Of the 36 seminomas studied, 22 (61%) expressed pEGFR. Ten samples exhibited high scores for pEGFR, pI3 k and pAkt. In 5 of 17 cases (33%) some mutation was exhibited in the exons studied: 21 of EGFR (2), 17 of EGFR (1), 3 of KRAS (1) and 11 of KIT (1). Six cases exhibited nuclear translocation of EGFR; of these, four exhibited mutations of EGFR, KRAS and KIT. Eight of ten of the GCNIS expressed a high pEGFR score (80%). In 2 of 6 cases (33%), mutation was detected in exon 21 of EGFR and one smear showed EGFR translocation to the nucleus. The translocation represents a subpopulation with worse prognosis for TCGT. The EGFR/pI3 k/Akt signaling pathway is linked to TDRG1, which regulates chemosensitivity to cisplatin; this is a mechanism of resistance to treatment. TDRG1 and the EGFR/pI3 k/pAkt pathway could be therapeutic targets for seminomas resistant to cisplatin.