Although HMGA1 (high-mobility group A1; formerly HMG-I/Y) is an oncogene that is widely overexpressed in aggressive cancers, the molecular mechanisms underlying transformation by HMGA1 are only beginning to emerge. HMGA1 encodes the HMGA1a and HMGA1b protein isoforms, which function in regulating gene expression. To determine how HMGA1 leads to neoplastic transformation, we looked for genes reg...

596 VOLUME 11 | NUMBER 6 | JUNE 2005 NATURE MEDICINE persistently activated in a human disease called anaplastic large cell lymphoma10. Chromosomal translocations join the nucleoplasmin gene to the gene that encodes ALK kinase, producing the persistently active NMP-ALK oncogene. To investigate the role of STAT3 in malignant transformation by NMP-ALK and in cancer cell survival, Chiarle et al.5 ...

Ovarian cancer's poor progression is closely associated with overexpression of matrix metalloproteinase 9 (MMP-9), which belongs to the class of enzymes believed to be involved in the degradation of extracellular matrix. However, the mechanisms underlying regulation of MMP-9 are not completely understood. STAT (signal transducer and activator of transcription) family of transcription factors is...

Background and Aims: Hepatocellular carcinoma (HCC) is one of the most important common cancers in the world. The main etiology of this cancer in developing and third world countries is due to the infection with hepatitis B and C viruses. Hepatitis B and C viruses (HCV) would both cause liver cancer but the incidence of the disease in relation to the age and gender has not been determined. The ...

The antiviral and antiproliferative responses mediated by type I interferons (IFNs) depend on JAK/STAT signaling and ISGF3 (STAT1:STAT2:IRF9)-dependent transcription. In addition, type I IFNs stimulate STAT3 activation in many cell types, an event generally associated with cell cycle progression, survival, and proliferation. To gather more insight into this functionally contradictive phenomenon...

Emerging evidence indicates a novel mode of epidermal growth factor receptor (EGFR) signaling, notably, one involves EGFR nuclear translocalization and subsequent gene activation. To date, however, the significance of the nuclear EGFR pathway in glioblastoma (GBM) is unknown. Here, we report that EGFR and its constitutively activated variant EGFRvIII undergo nuclear translocalization in GBM cel...

Abnormalities in signal transducer and activator of transcription 3 (STAT3) are involved in the oncogenesis of oral squamous cell carcinoma (OSCC). MicroRNA-21 (miR-21) is an important gene expression regulator to OSCC. miR-21 induction by STAT3 has been reported in multiple human cancers. In the present study, we found that STAT3 (-/p) expression was positively correlated with miR-21 in 60 OSC...

BACKGROUND Astrocytes exert a wide variety of functions in health and disease and respond to a wide range of signaling pathways, including members of the Janus-kinase signal transducers and activators of transcription (Jak-STAT) family. We have recently shown that STAT3 is an important regulator of astrocyte reactivity after spinal cord injury in vivo[1]. METHODOLOGY/PRINCIPAL FINDINGS Here, ...

Signal transducers and activators of transcription 3 (STAT3) was originally identified as a transcription factor that mediates cytokine-induced responses. In these pathways, Janus-activated kinase (JAK)-induced transient tyrosine phosphorylation of STAT3 promotes gene expression in response to a number of cytokines, which is inhibited by feedback mechanisms. A number of studies have shown that ...

STAT3 is a cardioprotective molecule against acute myocardial injury; however, recent studies have suggested that chronic STAT3 activation in genetically modified mice was detrimental after myocardial infarction (MI). In the present study, we assessed the biological significance of STAT3 activity in subacute MI using tamoxifen (TM)-inducible cardiac-specific STAT3 knockout (STAT3 iCKO) mice. Af...