Mouse Anti-Human Ki-67 monoclonal antibody, clone JID178

Irisin is an exercise-induced myokine that has various physiological functions, such as roles in energy expenditure, glucose/lipid metabolism, and muscle development. In muscle development, myoblast proliferation is known to be a first step, and recent studies have reported that an increased irisin level is involved in the promotion of cell proliferation in various cell types, including myoblasts. However, the exact mechanism of action by which irisin promotes myoblast proliferation has not been reported. In this study, we aimed to determine the pro-proliferative effect of irisin on C2C12 myoblasts and its mechanism of action. Irisin induced C2C12 cell proliferation and upregulated the mRNA levels of markers of proliferation Pcna, Mki67, and Mcm2. Irisin increased extracellular signal-regulated kinase (ERK) phosphorylation, and U0126, an ERK pathway inhibitor, suppressed irisin-induced C2C12 cell proliferation. Transcriptomic and qRT-PCR analysis showed that Ccl2, Ccl7, Ccl8, and C3 are potential downstream regulators of ERK signaling that promote C2C12 cell proliferation. Knockdown of Ccl7 revealed that irisin upregulates chemokine (C-C motif) ligand 7 (CCL7) and subsequently promotes C2C12 cell proliferation. These results suggest that irisin promotes C2C12 myoblast proliferation via ERK-dependent CCL7 upregulation and may aid in understanding how irisin contributes to muscle development.

Purpose: To evaluate altered protein expression with tissue microarray methodology for 15 different markers with potential prognostic significance in invasive bladder cancer. Materials and Methods: Invasive tumor was sampled with the tissue-arraying instrument in 133 consecutive patients who underwent radical cystectomy, and at least 3, 0.6-min tissue cores were obtained. With immunohistochemistry, the expressions of TP53, RB1, CDKN1A (p21), MKI67 (Ki67), PTGS2 (Cox-2), CTNNA1 (alpha-catenin), CTNNB1 (beta-catenin), AKT, PTEN, RHOA, RHOC, STAT1, VEGFC, EGFR, and ERBB2 (HER2) were quantified, and correlations were made with tumor grade, pathologic stage, lymph node status, and disease-specific survival. Results: Decreased immunohistochemical expression of CTNNA1 and of PTEN correlated with higher pathologic tumor stages (P = 0.01 and P = 0.01, respectively), whereas increased AKT1 and ERBB2 correlated with lower pathologic tumor stages (P = 0.01 and P = 0.03, respectively). Increased RHOA expression was more common in grade 3 than in grade 2 tumors (P = 0.016). There were no other correlations among the 15 factors studied and pathologic stage, lymph node status, or tumor grade. No association was found between bladder cancer death and altered marker status for my of the markers studied. Conclusions: Currently, there are reasons to have a skeptical attitude toward the value of tissue microarray based immunohistochemistry as a method for evaluating prognostic markers in invasive bladder cancer. In this study, 15 antibodies were tested but were found to be of little clinical value. Whether this negative finding is related to the group of patients or factors studied, or the methodology is unclear. (c) 2008 Elsevier Inc. All rights reserved.