OBJECTIVE Skeletal muscle regeneration is a complex process involving the coordinated input from multiple stimuli. Of these processes, actions of the insulin-like growth factor-I (IGF-I) and phosphoinositide 3-kinase (PI3K) pathways are vital; however, whether IGF-I or PI3K expression is modified during regeneration relative to initial damage intensity is unknown. The objective of this study wa...

Met(5)-enkephalin (ME)-induced cardioprotection occurs via epidermal growth factor receptor (EGFR) transactivation with the subsequent activation of phosphatidylinositol 3-kinase (PI3K). In the present study, we investigated whether there is a sex difference in ME-elicited PI3K signaling. Neonatal murine cardiomyocytes were isolated by collagenase digestion and subjected to 90 min hypoxia and 1...

A is emerging as a central player in tumorigenesis. In this issue of PNAS, Mayo and Donner (1) report on yet another function of AKT, involving regulation of the Mdm2yp53 pathway. The first evidence pointing to a role of AKT in oncogenesis was provided by early studies of transforming viruses. A novel retrovirus, isolated from an AKR mouse T cell lymphoma (2), harbored transduced sequences of c...

Skeletal muscle physiology and metabolism are regulated by complex networks of intracellular signaling pathways. Among many of these pathways, the protein kinase AKT plays a prominent role. While three AKT isoforms have been identified (AKT1, AKT2, and AKT3), surprisingly little is known regarding isoform-specific expression of AKT in human skeletal muscle. To address this, we examined the expr...

Malignant melanoma is the most deadly form of skin cancer due to its highly metastatic nature. Untargeted therapies are ineffective for treating metastatic disease, leading to the development of agents specifically inhibiting proteins or pathways deregulated in melanoma. The deregulation of inducible nitric oxide synthase (iNOS) is one such event occurring in melanoma, and is correlated with po...

OBJECTIVES Study of non-coding RNAs is considerable to elucidate principal biological questions or design new therapeutic strategies. miRNAs are a group of non-coding RNAs that their functions in PI3K/AKT signaling and apoptosis pathways after T cell activation is not entirely clear. Herein, miRNAs expression and their putative targets in the mentioned pathways were studied in the activated CD4...

AIM By tissue microarray methodology, the expression of altered Akt isoforms, PTEN and PI3K and their prognostic significance in 335 non-small cell lung cancer (NSCLC) tumors were investigated. PATIENTS AND METHODS Tumor tissue was sampled and immunohistochemically quantified in 335 tumors from stage I to IIIA NSCLC patients both from tumor epithelial cells and surrounding stromal tissue in r...