Mechanistically, calcitriol suppressed EMT through different signaling pathways: (1) calcitriol suppressed Smad2/3 phosphorylation through reinforcing physical interaction between vitamin D receptor (VDR) and Smad3 in TGF-β1-stimulated RCC cells; (2) calcitriol inhibited STAT3 activation in LPS-stimulated RCC cells; (3) calcitriol inhibited β-catenin/TCF-4 activation through promoting integration of VDR with β-catenin in TGF-β1-unstimulated RCC cells.
This study was aimed to investigate the functional role of miR-125a and the expression relevance of signal transducers and activators of transcription 3 (STAT3) with hyaluronic acid synthase 1 (HAS1) in RCC.
Results from in vitro cellular experiments suggest that the mutant TSC2 proteins were quickly degraded and they failed to repress the phosphorylation of S6K1 and STAT3, which leads to constitutive activation of mTORC1 pathway and ultimately cause the development of RCC.
This retrospective study aimed to elucidate the association of STAT3 expression in tumor cells with the therapeutic outcomes of sunitinib in patients with renal cell carcinoma (RCC).
Remarkably, knockdown of G3BP1 dramatically impaired the signaling connection of pro-inflammatory cytokine IL-6 stimulation and downstream STAT3 activation in RCC, thus eventually contributing to the disruption of IL-6-elicited RCC migration and metastasis.
The pharmacological effect of zerumbone on STAT3 activation, associated protein kinases and phosphatase, and apoptosis was investigated using both RCC cell lines and xenograft mouse model.
In this study, CXCR2 and SOCS-3 were immunohistochemically investigated in 118 RCC cases in relation to interleukin (IL)-6 and (IL)-8, their downstream transducer phosphorylated (p-)STAT-3, and VEGF expression, being further correlated with microvascular characteristics, clinicopathological features and survival.
Collectively, our results describe a functionally distinct, noncanonical STAT3 phosphoform that positively regulates target gene expression in a combinatorial signaling context and identify GSK-3α/β-STAT3 signaling as a potential therapeutic target in renal-cell carcinoma.
Data from this study thus provide in vitro evidence supporting the notion that luteolin is a potential sensitizer of TRAIL in anticancer therapy against human RCC involving Akt and STAT3 inactivation.
Silibinin inhibited phosphorylation of EGFR and its downstream molecules ERK1/2 but did not affect phosphorylation of other downstream molecules, STAT3 and Akt, in human RCC cell lines.
These compounds reduced basal STAT3 phosphorylation (pSTAT3), and induced apoptosis in four separate human RCC cell lines and in human melanoma cell lines as determined by Annexin V/PI staining.
These results suggest that Stat3 activity is important for RCC response to sunitinib, and Stat3 inhibition permits the direct proapoptotic activity of sunitinib on tumor cells and positive effects on tumor immunologic microenvironment.
We examined 48 paraffin embedded renal cell carcinoma specimens and corresponding nonneoplastic kidney tissues for the activation status of STAT3 on immunohistochemistry using anti-phospho-specific (p)-STAT3 antibody, which recognizes only activated STAT3.