Disease relevance of EXOSC7

• However, the expression of p8 in pancreatic cancer is not reported [1].
• The p8 gene is a recently identified gene with mitogenic activity. p8 expression is induced in acute pancreatitis, pancreatic development, and regeneration [1].
• We investigated p8 expression in 72 human pancreatic tissues, including 38 pancreatic cancers (PCs), by immunohistochemistry. p8 was overexpressed (positive cells >25% in 1,000 cells) in 71% (27 of 38) of PCs, but in only 17% (3 of 18) of chronic pancreatitis cases [1].
• On the other hand, p8 localization was more cytoplasmic in papillary carcinoma larger than 1.0 cm (p=0.0186) and with a poorly differentiated lesion (p=0.0313) [2].
• All non-invasive ductal carcinomas diffusely expressed p8 [3].

High impact information on EXOSC7

• Identification of the endophilins (SH3p4/p8/p13) as novel binding partners for the beta1-adrenergic receptor [4].
• N-terminal amino acid sequence analysis of p8 revealed homology with the calcium-binding myeloid related protein (MRP-8) [5].
• The antibody recognized in particular an 8-kDa protein (p8) in resting human neutrophil cytosol and in the membrane of zymosan-activated cells [5].
• p8 is a new target of gemcitabine in pancreatic cancer cells [6].
• These results suggest that, in pancreatic cancer cells, a large part of gemcitabine-induced apoptosis results from the inhibition of the constitutive antiapoptotic activity of p8 [6].

Biological context of EXOSC7

• We demonstrate that the two human proteins hCsl4p and hRrp42p, which have been identified on the basis of their sequence homology with Saccharomyces cerevisiae proteins, are associated with the human exosome [7].
• The p8 gene comprises three exons separated by two introns and the gene was mapped to chromosome 16 [8].
• To analyze the p8 function, we stably transfected HeLa cells with a p8 expression plasmid, and measured their growth and their sensitivity to apoptosis [8].
• This presumption has been confirmed by transfection of COS-7 cells with the p8 cDNA followed by immunostaining with specific antibodies. p8 mRNA expression is induced in some, but not all, cells by serum starvation and ceramide [8].
• p8 is a widely expressed HMG-I/Y-like transcription factor which is involved in regulating cell proliferation and tissue stress [9].

Anatomical context of EXOSC7

• Reverse transcription-PCR analysis confirmed p8 mRNA overexpression (tumor/nontumor ratio >2) in 75% (3 of 4) of PCs. p8 was overexpressed also in human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1) [1].
• We have previously identified a new rat mRNA, provisionally named p8, which showed a strong, but transient, induction in the pancreas in response to acute pancreatitis [8].
• Expression and cellular localization of p8 protein in thyroid neoplasms [2].
• The p8 expression level was directly linked to lymph node metastasis, extrathyroid extension and UICC stage [10].
• Subcutaneous or intraperitoneal injections of transformed p8-expressing fibroblasts led to tumor formation in nude mice, but no tumor was observed with transformed p8-deficient cells [11].

Associations of EXOSC7 with chemical compounds

• We found that (a) knocking down p8 expression in gemcitabine-resistant cells promoted cell death and increased caspase-3 activity; (b) forced overexpression of p8 in gemcitabine-sensitive cells increased their resistance to gemcitabine-induced apoptosis; and (c) gemcitabine down-regulated p8 mRNA expression [6].
• Characterization of glutathione S-transferase from dust mite, Der p 8 and its immunoglobulin E cross-reactivity with cockroach glutathione S-transferase [12].

Other interactions of EXOSC7

• The hRrp4p and hRrp42p components were most frequently targeted [13].

Analytical, diagnostic and therapeutic context of EXOSC7

• IgE reactivity to native and recombinant Der p 8 was assessed by ELISA using sera from allergic subjects from Taiwan, Singapore and Malaysia. IgE cross-reactivity between Der p 8 and cockroach GST was examined by IgE inhibition assays [12].

References