The polarity of the spermatozoon is clearly demonstrated by the acrosome at the apical pole of the cell and the flagellum at the opposite end. Spermatogenesis
consists of three basic phases: mitosis, meiosis and spermiogenesis. The final phase represents the period of greatest cellular change where cell-type specific organelles such as the acrosome and the flagellum form, the nucleus migrates to the plasma membrane and elongates, chromatin condenses and residual cytoplasm is removed. An important feature of spermatogenesis is the change in the cytoskeleton that occurs throughout this pathway. In this review, the author will provide an overview of these transformations and provide insight into possible modes of regulation of these rearrangements during spermatogenesis. Although primary focus will be given to the microtubule cytoskeleton, the importance of actin filaments to the cellular transformation of the male germ cell will also be discussed.”
“Developing CBL0137 proteomic biomarkers is valuable for evaluating therapeutic effects of drugs and generating better treatment strategies. However, conventional protein analysis
is often challenging due to inadequate sample size of clinical specimens, lack of assay reproducibility, accuracy, and sensitivity. A novel capillary isoelectricfocusing (IEF) immunoassay GS-7977 datasheet system (NanoPro) was used to study the dynamic phosphorylation status of signaling molecules in non-small cell lung cancer (NSCLC) cells treated with EGFR tyrosine kinase and MEK inhibitors. NanoPro showed the same dynamic ERK phosphorylation as Western blotting with good assay reproducibility using 1,000 times less protein. The IEF separation in NanoPro system enables multiple protein phosphorylation isoforms to be resolved and detected simultaneously. With NanoPro, we identified a specific on-target mitogen-activated protein/extracellular signal-regulated kinase (MEK) response pattern to MEK inhibitor PD325901, which was not detectable by Western blot analysis. We also revealed a MEK2 signal that may be associated with NSCLC cell sensitivity to the EGF receptor inhibitor erlotinib, and distinguished erlotinib-sensitive cells
from intrinsic as well as acquired resistant cells to erlotinib. Moreover, NanoPro could differentiate human ERK1 isoforms from the mouse isoforms based SRT1720 manufacturer on their isoelectric point differences and showed that erlotinib effectively inhibited ERK phosphorylation in targeted human xenograft cancer cells but not in surrounding mouse stromal cells. With 8 mu g of tumor aspirates, we precisely quantified the response of 18 signaling molecules to erlotinib and MEK1 inhibitor treatments in an NSCLC patient. NanoPro’s higher sensitivity, better resolution of protein phosphorylation status, and reduced tissue requirement warrant NanoPro’s investigation for future drug development and evaluation of drug effects of targeted therapies. Mol Cancer Ther; 12(11); 2601-13. (C) 2013 AACR.