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Purpose The purpose of this study was to examine the regulation of renal organic ion transporters in cisplatin-induced acute kidney injury (AKI) and its relation with indoxyl sulfate (IS), a uremic toxin. Methods The IS concentrations in the serum and kidney were monitored by high-performance liquid chromatography. Uptake of p-aminohippuric acid, estrone-3-sulfate and tetraethylammonium were examined using renal slices. Real-time PCR and immunoblotting were performed to examine the mRNA and protein expression of rOATs, rOCTs and rMATE1 in the kidney, respectively. Results The serum and renal IS levels were markedly elevated in cisplatin-treated rats. However, this effect was largely reversed by administration of AST-120, an oral charcoal adsorbent. The functions of renal basolateral organic anion and cation transporters were reduced in cisplatin-treated rats. The levels of mRNA and protein corresponding to rOAT1, rOAT3, rOCT2 and rMATE1, but not rOCT1, were depressed in the kidney of cisplatin-treated rats. Administration of AST-120 to cisplatin-treated rats partially restored the function and expression level of these transporters. Conclusions Cisplatin-induced AKI causes down-regulation of renal organic ion transporters accompanied by accumulation of serum and renal IS. IS could be involved in the mechanism of down-regulation of rOAT1, rOAT3 and rMATE1 under cisplatin-induced AKI.

We have previously described a method for adoptive immunotherapy of cancer based on antigen-specific T(h)1 cells. However, efficient induction of anti-tumor responses using T(h)1 cells remains a formidable challenge, especially for MHC class II-negative tumors. In the present study, we sought to develop a novel strategy to eradicate established tumors of the MHC class II-negative, ovalbumin (OVA)-expressing EG-7 cells. Tumor-bearing mice were intradermally treated with OVA-specific T(h)1 cells, combined with the model tumor antigen (OVA), near the tumor-draining lymph node (DLN). We found that tumor growth was significantly inhibited by this strategy and approximately 50-60% of tumor-bearing mice were completely cured. Tumor eradication was crucially dependent on the generation of OVA/H-2K(b)-specific CTLs in the tumor DLNs and tumor site. The injected T(h)1 cells were mainly distributed in tumor DLNs, where they vigorously proliferated and enhanced the activation of dendritic cells. Strikingly, we also found that the accumulation of CD4(+)CD25(+) regulatory T cells (Tregs) was significantly inhibited in tumor DLNs by T(h)1 cell adjuvant therapy and this abrogation was associated with IFNgamma secreted by T(h)1 cells. These results identify T(h)1 cell adjuvant therapy combined with tumor vaccination as a novel approach to the treatment of human cancer.

A 39-year-old Japanese woman presented with a swollen right hand and a right-sided pneumothorax. Chest CT revealed bilateral multiple pulmonary thin-walled cysts measuring

The serine/threonine kinase, Akt (protein kinase B) plays a central role in the regulation of intracellular cell survival. Recently, we demonstrated that the proto-oncogene TCL1, overexpressed in human T-cell prolymphocytic leukemia, is an Akt kinase co-activator. Tightly restricted TCL1 gene expression in early developmental cells suggested that the TCL1 gene is regulated at a transcriptional level. To characterize how TCL1 gene expression is regulated, we cloned the 5'-promoter of the TCL1 gene located at human chromosome 14q32. The 5'-TCL1 promoter region contains a TATA box with cis-regulatory elements for Nur77/NGFI-B (nerve growth factor-responsive element (NBRE), CCAAGGTCA), NFkappaB, and fork head transcription factor. Nur77/NGFI-B, an orphan receptor superfamily transcription factor implicated in T-cell apoptosis, is a substrate for Akt. We hypothesized that TCL1 transactivity is regulated through Akt-induced phosphorylation of Nur77/NGFI-B in vivo. In an electrophoretic mobility shift assay with chromosomal immunoprecipitation assays, wild-type Nur77, but not S350A mutant Nur77, could specifically bind to TCL1-NBRE. A luciferase assay demonstrated that TCL1-NBRE is required for inhibition of TCL1 transactivity upon nerve growth factor/platelet-derived growth factor stimulation, which activates Akt and phosphorylates Nur77. Using a chromosomal immunoprecipitation assay with reverse transcription-PCR, nerve growth factor stimulation inhibited binding of endogenous Nur77 to TCL1-NBRE, in turn, suppressing TCL1 gene expression. The results together establish that TCL1-NBRE is a novel negative regulatory element of Nur77 (NGFI-B). To the best of our knowledge, TCL1-NBRE is the first direct target of Nur77 involving the regulation of intracellular cell death survival. This Akt-induced inhibitory mechanism of TCL1 should play an important role in immunological and/or neuronal development in vivo.

Epithelial-mesenchymal transition (EMT) describes a process occurring during development and oncogenesis by which epithelial cells obtain fibroblast-like properties and show reduced cell adhesion and increased motility. In this report, we demonstrated typical EMT in human mammary epithelial MCF10A small interfering (si)RNA gelsolin-knockdown cells. EMT was characterized by fibroblastic morphology, loss of contact inhibition and focus formation in monolayer growth, enhanced motility and invasiveness in vitro, increased actin filaments, overexpression of RAC, activation of both extracellular signal-regulated kinase and AKT, inactivation of glycogen synthase kinase-3, conversion of cadherin from the E- to N-type and induction of the transcription factor Snail. These results suggested that gelsolin functions as a switch that controls E- and N-cadherin conversion via Snail, and demonstrated that its knockdown leads to EMT in human mammary epithelial cells and possibly to the development of human mammary tumors.

Human HOX genes consist of 39 genes and encode transcription factors that function as master developmental regulators. We hypothesized that the misexpression of HOX genes was associated with carcinogenesis and malignant progression. The expression levels of 39 HOX genes in 31 human oral squamous cell carcinoma (SCC), 11 dysplasia, and 10 normal mucosa tissues were quantified by the real-time RT-PCR method. The expression levels of 18 HOX genes in the SCC tissues were significantly higher than those in the normal mucosa tissues. The dysplasia tissues showed higher expression of HOXA2, A3, B3, and D10 than normal mucosa tissues whereas they showed lower expression of HOXA1, B7, B9, and C8 than SCC. The SCC with lymph node metastasis showed high expression of HOXC6 compared to the SCC without it. These results suggest that misexpressions of particular HOX genes are implicated in the development of oral dysplasia and SCC.