RESUMO
CSN6 is one subunit of the highly conserved constitutive photomorphogenesis 9 (COP9) signalosome (CSN), which is overexpressed in many types of cancers, and has received great attention as a regulator of the degradation of cancer-related proteins, suggesting its importance in oncogenic activity. CSN6 has been shown to be overexpressed in cervical cancer (CC) and associated with CC development. CC remains to be one of the most aggressive cancers affecting women. Cathepsin L (CTSL), significantly associated with the autophagy, plays a critical role in degradation of extracellular matrix for metastasis. However, the detailed biological functions of CSN6 on CTSL in CC metastasis have not been well clarified. Our data has shown that CSN6 and CTSL are positively correlated. The overexpression of CSN6 and CTSL might be a strong indicator for CC enhanced aggressiveness. CSN6 could suppress the degradation of CTSL, then facilitated the migration and invasion of CC cells. Interestingly, our results indicated that autophagy is essential for decreasing CTSL, while CSN6 could inhibit the autophagy ability of CC cells. In addition, blocking of the mammalian target of rapamycin (mTOR) pathway reversed CSN6-mediated autophagy inhibition. We further demonstrated that CSN6 positively regulated CTSL expression through an autophagy-lysosomal system. Taken together, we concluded that CSN6 might promote the migration and invasion of cervical cancer cells by inhibiting autophagic degradation of CTSL and serve as a potential gene therapy target for the treatment of CC metastasis.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Complexo do Signalossomo COP9/fisiologia , Catepsina L/metabolismo , Invasividade Neoplásica/genética , Neoplasias do Colo do Útero/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Autofagia , Biomarcadores Tumorais/metabolismo , Complexo do Signalossomo COP9/genética , Complexo do Signalossomo COP9/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estabilidade Proteica , Serina-Treonina Quinases TOR/metabolismo , Ubiquitinação , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismoRESUMO
Peripheral lymphadenopathy is a rare presentation in malignant mesothelioma. We describe a unique case of malignant mesothelioma arising in an 11-year-old boy, for whom peripheral lymphadenopathy was the initial manifestation of the disease. The final diagnosis was confirmed by a broad panel of immunohistochemical markers. Literature review disclosed only 2 cases in childhood that initially presented with peripheral lymphadenopathy. Pathologists should be aware of this rare biologic behavior of malignant mesothelioma to reach the correct and prompt diagnosis.
