Involvement of L-type Ca²âº channel and toll-like receptor-4 in nickel-induced interleukin-8 gene expression.

The metal nickel (Ni(2+)) is found everywhere in our daily lives, including coins, costume jewelry, and even nuts and chocolates. Nickel poisoning can cause inflammatory reactions, respiratory diseases, and allergic contact dermatitis. To clarify the mechanism by which nickel induces mediators of inflammation, we used the human acute monocytic leukemia THP-1 cell line as a model. Interleukin (IL)-8 promoter activity as well as gene expression were tested by luciferase assay and real-time polymerase chain reaction. The underlying mechanisms of nickel-induced IL-8 were investigated. We found that nickel induced IL-8 gene expression via the L-type Ca(2+) channel, Toll-like receptor-4 (TRL-4) and nuclear factor NF-κB signal transduction pathways. Nickel activated NF-κB expression through extracellular signal-regulated kinase 1/2 phosphorylation and then increased IL-8 expression. Thus, the L-type Ca(2+) channel and TRL-4 play important roles in nickel-induced inflammatory gene expressions.

Involvement of STIM1 and Orai1 in EGF-mediated cell growth in retinal pigment epithelial cells.

BACKGROUND: In non-excitable cells, one major route for calcium entry is through store-operated calcium (SOC) channels in the plasma membrane. These channels are activated by the emptying of intracellular Ca²âº store. STIM1 and Orai1 are major regulators of SOC channels. In this study, we explored the functions of STIM1 and Orai1 in epidermal growth factor (EGF)-induced cell proliferation and migration in retinal pigment epithelial cells (ARPE-19 cell line). RESULTS: EGF triggers cell proliferation and migration in ARPE-19 cells. Cell proliferation and migration involve STIM1 and Orai1, as well as phosphorylation of extracellular signal-regulated protein kinase (ERK) 1/2, and Akt. Pharmacological inhibitors of SOC channels and siRNA of Orai1 and STIM1 suppress cell proliferation and migration. Pre-treatment of mitogen-activated protein kinase kinase (MEK) inhibitors and a phosphatidylinositol 3 kinases (PI3K) inhibitor attenuated cell proliferation and migration. However, inhibition of the SOC channels failed to prevent EGF-mediated ERK 1/2 and Akt phosphorylation. CONCLUSIONS: Our results showed that STIM1, Orai1, ERK 1/2, and Akt are key determinants of EGF-mediated cell growth in ARPE-19 cells. EGF is a potent growth molecule that has been linked to the development of PVR, and therefore, STIM1, Orai1, as well as the MEK/ERK 1/2 and PI3K/Akt pathways, might be potential therapeutic targets for drugs aimed at treating such disorders.

A soft coral natural product, 11-episinulariolide acetate, inhibits gene expression of cyclooxygenase-2 and interleukin-8 through attenuation of calcium signaling.

Epidermal growth factor receptor (EGFR) is overexpressed in many types of cancer cells. EGFR-mediated signaling involves inflammatory gene expression including cyclooxygenase (COX)-2 and interleukin (IL)-8, and is associated with cancer pathogenesis. In a search of phytochemicals with anti-inflammatory activity, the COX-2 and IL-8 inhibitory activities of some marine compounds were examined. After screening these compounds 11-episinulariolide acetate (1) from soft coral exhibited the most potent activity. Reverse-transcription PCR; western blotting; ELISA and luciferase assays were used to test the effect of compound 1 on EGF-stimulated expressions of COX-2 and IL-8 in A431 human epidermoid carcinoma cells. After exposure to 10 µM of compound 1, expression levels of COX-2 and IL-8 were reduced. In addition; intracellular Ca²âº increase and Ca²âº-dependent transcription factor activation were blocked by compound 1. Thus, compound 1 can potentially serve as a lead compound for targeting Ca²âº signaling-dependent inflammatory diseases.

Indomethacin inhibits cancer cell migration via attenuation of cellular calcium mobilization.

Non-steroidal anti-inflammatory drugs (NSAIDs) were shown to reduce the risk of colorectal cancer recurrence and are widely used to modulate inflammatory responses. Indomethacin is an NSAID. Herein, we reported that indomethacin can suppress cancer cell migration through its influence on the focal complexes formation. Furthermore, endothelial growth factor (EGF)-mediated Ca2+ influx was attenuated by indomethacin in a dose dependent manner. Our results identified a new mechanism of action for indomethacin: inhibition of calcium influx that is a key determinant of cancer cell migration.

Functional Effects of let-7g Expression in Colon Cancer Metastasis.

MicroRNA regulation is crucial for gene expression and cell functions. It has been linked to tumorigenesis, development and metastasis in colorectal cancer (CRC). Recently, the let-7 family has been identified as a tumor suppressor in different types of cancers. However, the function of the let-7 family in CRC metastasis has not been fully investigated. Here, we focused on analyzing the role of let-7g in CRC. The Cancer Genome Atlas (TCGA) genomic datasets of CRC and detailed data from a Taiwanese CRC cohort were applied to study the expression pattern of let-7g. In addition, in vitro as well as in vivo studies have been performed to uncover the effects of let-7g on CRC. We found that the expression of let-7g was significantly lower in CRC specimens. Our results further supported the inhibitory effects of let-7g on CRC cell migration, invasion and extracellular calcium influx through store-operated calcium channels. We report a critical role for let-7g in the pathogenesis of CRC and suggest let-7g as a potential therapeutic target for CRC treatment.

A Novel Strategy for TNF-Alpha Production by 2-APB Induced Downregulated SOCE and Upregulated HSP70 in O. tsutsugamushi-Infected Human Macrophages.

Orientia (O.) tsutsugamushi-induced scrub typhus is endemic across many regions of Asia and the Western Pacific, where an estimated 1 million cases occur each year; the majority of patients infected with O. tsutsugamushi end up with a cytokine storm from a severe inflammatory response. Previous reports have indicated that blocking tumor necrosis factor (TNF)-α reduced cell injury from a cytokine storm. Since TNF-α production is known to be associated with intracellular Ca2+ elevation, we examined the effect of store-operated Ca2+ entry (SOCE) inhibitors on TNF-α production in O. tsutsugamushi-infected macrophages. We found that 2-aminoethoxydiphenyl borate (2-APB), but not SKF96365, facilitates the suppression of Ca2+ mobilization via the interruption of Orai1 expression in O. tsutsugamushi-infected macrophages. Due to the decrease of Ca2+ elevation, the expression of TNF-α and its release from macrophages was repressed by 2-APB. In addition, a novel role of 2-APB was found in macrophages that causes the upregulation of heat shock protein 70 (HSP70) expression associated with ERK activation; upregulated TNF-α production in the case of knockdown HSP70 was inhibited with 2-APB treatment. Furthermore, elevated HSP70 formation unexpectedly did not help the cell survival of O. tsutsugamushi-infected macrophages. In conclusion, the parallelism between downregulated Ca2+ mobilization via SOCE and upregulated HSP70 after treatment with 2-APB against TNF-α production was found to efficiently attenuate an O. tsutsugamushi-induced severe inflammatory response.

Study of the association between ITPKC genetic polymorphisms and calcium nephrolithiasis.

Nephrolithiasis is a multifactorial disease caused by environmental, hormonal, and genetic factors. Genetic polymorphisms of ORAI1, which codes for the main subunit of the store-operated calcium (SOC) channel, were reported to be associated with the risk and recurrence of calcium nephrolithiasis. Inositol 1,4,5-trisphosphate (IP3) 3-kinase C (ITPKC) is a negative regulator of the SOC channel-mediated signaling pathway. We investigated the association between calcium containing nephrolithiasis and genetic variants of ITPKC gene in Taiwanese patients. 365 patients were recruited in this study. Eight tagging single nucleotide polymorphisms of ITPKC were selected for genotyping. ITPKC genotypes were determined by TaqMan assay. ITPKC plasmids were transfected into cells to evaluate the intracellular calcium mobilization. Our results indicated that rs2607420 CC genotype in the intron region of the ITPKC gene is associated with a lower eGFR by both Modification of Diet in Renal Diseases (P = 0.0405) and Cockcroft-Gault (P = 0.0215) equations in patients with calcium nephrolithiasis. Our results identify a novel polymorphism for renal function and highlight the importance of ITPKC as a key molecule to regulate calcium signaling.

Comparison one-step procedure with two-step procedure in percutaneous nephrolithotomy.

The aim of this study was to compare the effects of one-step percutaneous nephrolithotomy (PCNL) by the urologist alone and two-step PCNL by cooperating with the radiologist. We included 168 patients who underwent surgery by the same surgeon, 83 who underwent two-step PCNL, in which percutaneous nephrostomy insertion was performed by the radiologists on the day before endo-surgery, and 85 who underwent one-step PCNL, which involved the creation of a nephrostomy tract and performing the PCNL at the same time in the operating room, by a urologist. We compared the perioperative and postoperative parameters between these two groups. The result revealed that there were no significant differences between one-step and two-step PCNL in the decreases in haemoglobin level and blood transfusion volume, and the hospital stay was shorter in the one-step PCNL group. In addition, the one-step PCNL group was associated with significantly lower visual analogue score (VAS), which were 2.3, 1.1, and 0.4 on the post-operative days 1, 2, and 3, respectively, compared with 3.2, 1.7, and 1.0 in the two-step PCNL group. The number of parenteral analgesic prescriptions was fewer in the one-step PCNL group (0.8 ± 1.1 amps/vials) than in the two-step PCNL group (4.1 ± 2.4 amps/vials). Furthermore, different stone locations barely affected VAS and analgesic administrations. The results indicate that the one-step PCNL by the urologist alone, compared to two-step PCNL with the radiologist, has better wound pain outcome and shorter hospital stay with comparable successful rate and complication grade.

Cox-2 gene overexpression in ureteral stump urothelial carcinoma following nephrectomy for renal cell carcinoma: a case report.

INTRODUCTION: A primary ureteral stump tumor after a nephrectomy is rare; urothelial carcinoma of the ureteral stump after a nephrectomy for renal cell carcinoma is even rarer. A thorough review of the literature indicated that only seven cases have previously been reported. In this study, we report the first Taiwanese case of urothelial carcinoma of the ureteral stump after a nephrectomy. It is also the first female case in the literature. The relationship between inflammatory genes, medication history and ureteral stump carcinoma after a nephrectomy for renal cell carcinoma has not been reported. CASE PRESENTATION: A 72-year-old Asian Taiwanese women with chronic hepatitis C, liver cirrhosis and chronic kidney disease underwent a hand-assisted laparoscopic radical nephrectomy in 2001 due to renal cell carcinoma. Nine years later, she was diagnosed with ureteral stump urothelial carcinoma. Genetic and medication surveys were performed. Importantly, our patient had taken Chinese herbal drugs for more than 10 years and the inflammatory gene, Cox-2, was highly expressed in this patient. This is the first report to study the relationship between the Cox-2 gene and ureteral stump carcinoma after a nephrectomy for renal cell carcinoma. CONCLUSION: Long-term multiple use of Chinese herbal drugs could be one of the important risk factors for developing urothelial cancer. Close functional coupling between Chinese herbal drugs, Cox-2 gene activation and urothelial cancer should be further investigated.

R450H TSH receptor mutation in congenital hypothyroidism in Taiwanese children.

BACKGROUND: The most common congenital endocrine disorder, congenital hypothyroidism (CHT), is strongly associated with thyroid hormone deficiency. Previous studies have indicated that mutations of thyroid stimulation hormone receptor (TSHR) are a risk factor for the development of congenital hypothyroidism. One mutation of TSHR, p.R450H, is particularly frequent in Japanese children with CHT. However, the frequency of this TSHR mutation among Taiwanese patients with CHT is unclear. METHODS: We enrolled 149 CHT patients and 334 healthy subjects who volunteered to participate in health screening examinations. We characterized the clinical status of CHT patients with the TSHR mutations. RESULTS: There was a significant association between the TSHR mutation (p.R450H) and the risk of CHT (P=0.0008 under the dominant model and P=0.0002 under the allelic model). The frequency of homozygous p.R450H in the CHT patients was 1.4% and that of heterozygous p.R450H was 5.6%. All five patients had elevated serum TSH levels. However, there was no difference in TSH levels between those with heterozygous and homozygous p.R450H mutations. CONCLUSION: Approximately 7% of the patients in this study with CHT had heterozygous or homozygous TSHR mutations (c.1349G>A, p.R450H). Consistent with previous reports on Japanese populations, this mutation was relatively important in the Taiwanese children with CHT.