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Parkin (PARK2) is one of the largest genes in the human genome encoding for an E3 ubiquitin ligase. Its mutation is the cause of early-onset Parkinson’s disease, but recently it is linked to other pathologies including cancer. Parkin acts as a tumor suppressor. It displays a wide neuroprotective activity by promoting the removal of damaged mitochondria via mitophagy and increasing proteasomal degradation of toxic substrates. PARK2 primary transcript undergoes to an extensive alternative splicing, which enhances transcriptomic diversification and protein diversity in tissues and cells. To date, GenBank lists 26 human PARK2 transcripts corresponding to 21 different alternative splice variants. These transcripts show different expression patterns and encode for proteins with different functions, molecular weight and isoelectric point. Previous studies identified inactivating somatic mutations and frequent intragenic deletions of PARK2 in human cancers including gliomas (Veeriah et al., 2010). Recently, it has been demonstrated that Parkin pathway activation is predictive for the survival outcome of patients with glioma (Yeo et al., 2012). However, these papers focused on the expression of full length Parkin. In the present work we analyzed the expression pattern of Parkin isoforms in astrocytomas of different grade and we investigated their functions in a human glioblastoma multiforme cell line. Immunoblotting analysis by using two specific antibodies revealed that Parkin expression is generally higher in malignant glioblastoma than in less invasive astrocytomas, indicating a correlation between expression pattern of Parkin isoforms and tumor malignancy. Serum deprivation or treatment with a proteosome inhibitor MG132 or with carbonyl cyanide 3-chlorophenylhydrazone (CCCP), an uncoupling agent that dissipates the cells mitochondrial membrane potential, increased expression of 100-55-50 kDa parkin isoforms in glioma cells as compared to controls. These results, consistent with other studies, demonstrated a functional connection between Parkin expression, mitochondrial integrity and endoplasmic reticulum stress (Bouman et al., 2011). Parkin isoforms expression was also confirmed by confocal microscopy analysis. These results suggest that the characterization of some PARK2 isoforms may be usefull clinically to develop a prognostic tool in patients with brain tumor., Italian Journal of Anatomy and Embryology, Vol 119, No 1 (Supplement) 2014

We report rare case of myofibroblastoma (MFB) of the breast comprised predominantly of a mature fatty component, representing approximately 70% of the entire tumour area. This tumour, designated "lipomatous MFB", should be interpreted as the morphological result of an unbalanced bidirectional differentiation of the precursor mammary stromal cell, with the adipocytic component overwhelming the fibroblastic/myofibroblastic one. Lipomatous MFB is a rare variant of mammary MFB, which can mimic malignancy because of the close juxtaposition of fibroblasts/myofibroblasts with mature adipocytes, resulting in a finger-like infiltrative growth pattern of the former towards the latter. Histogenetic considerations and differential diagnostic problems with other bland-looking spindle cell tumours containing infiltrating fat are provided.

PARK2, also known as parkin, is a gene mutated in autosomal recessive juvenile parkinsonism and it has been shown to exhibit E3 ubiquitin ligase activity. However it seems to fulfill also a wide spectrum of protective functions. Recent studies have demonstrated that parkin is an important regulator of process that maintain mitochondrial quality and it is also implicated in proteasomal degradation of toxic substrates. This gene has been also shown to be genetically altered and/or aberrantly expressed in a wide variety of human cancers including lung cancer (Cesari et al., 2003; Veeriah S. et al., 2010). Although many alternatively spliced isoforms have been identified, until now studies have been focused on the full-length isoform (D’Agata and Cavallaro, 2004). To characterize the role of parkin isoforms in lung tumorigenesis we analyzed their expression pattern in human lung adenocarcinomas. These data were correlated to their expression pattern either in human lung epithelial carcinoma (A549) or in human normal bronchial epithelial (BEAS-2B) cell lines. Western blot and immunofluorescence analyses were performed by using two antibodies recognizing different domains of the full length protein. Immunoblots showed that lung adenocarcinomas express parkin isoforms of 50, 37 and 20 kDa. Their expressions were significantly increased in A549 as compared to BEAS-2B, suggesting that parkin isoforms might be involved in cancer progression. In order to characterize some functions of these isoforms, both cell lines were cultured in complete medium or serum starved medium and treated with the proteasome inhibitor MG132 or with carbonyl cyanide 3- clorophenylhydrazone (CCCP), a uncoupling agent that dissipates the mitochondrial membrane. Data obtained revealed that each treatment affects pattern expression of parkin isoforms. These results suggest that some parkin isoforms might be molecular markers of lung adenocarcinoma., Italian Journal of Anatomy and Embryology, Vol 119, No 1 (Supplement) 2014