Real-world safety and effectiveness of canakinumab in patients with tumour necrosis factor receptor-associated periodic syndrome or hyperimmunoglobulinaemia D syndrome: Interim results from post-marketing surveillance in Japan.

OBJECTIVES: To assess the real-world safety and effectiveness of canakinumab in patients in Japan with tumour necrosis factor receptor-associated periodic syndrome (TRAPS) or mevalonate kinase deficiency/hyperimmunoglobulinaemia D with periodic fever syndrome (MKD/HIDS). METHODS: All patients with TRAPS or MKD/HIDS who received canakinumab following drug approval in Japan were registered in a post-marketing all-patient surveillance with a 2-year observation period. Herein, the interim results are reported. RESULTS: Fifteen patients with TRAPS and seven with MKD/HIDS were included in the safety and effectiveness analysis set. Adverse drug reactions were reported in 26.67% (n = 4) and 42.86% (n = 3) of TRAPS and MKD/HIDS patients, respectively. Most common adverse drug reactions were upper respiratory tract inflammation (13.33%, n = 2) and pyrexia (42.86%, n = 3) in TRAPS and MKD/HIDS patients, respectively. No serious adverse drug reactions were observed in either TRAPS or MKD/HIDS patients. The proportion of responders was 46.67% and 14.29% in the TRAPS and MKD/HIDS groups, respectively; 72.73% and 66.67% achieved clinical remission, while 90.91% and 66.67% achieved serological remission by Week 4 in the TRAPS and MKD/HIDS groups, respectively. CONCLUSIONS: These interim results provide the first evidence of the real-world effectiveness of canakinumab in patients with TRAPS or MKD/HIDS in Japan. No new safety concerns were identified.

Impact of Tight Junction Protein ZO-1 and TWIST Expression on Postoperative Survival of Patients with Hepatocellular Carcinoma.

BACKGROUND: Epithelial-mesenchymal transition (EMT) is considered to play a critical role in cancer progression and metastasis. However, the impact of EMT on the prognosis of hepatocellular carcinoma (HCC) is still elusive. In this study, we examined the relationship between the expression of EMT markers and recurrence-free survival (RFS) and overall survival (OS) in HCC patients after hepatic resection. SUMMARY: The mRNA expression of 15 genes related to EMT was assessed by quantitative real-time polymerase chain reaction in cancerous tissues from 72 patients who underwent hepatic resection of HCC between January 2005 and December 2010 at our hospital. The upregulation of TWIST and the downregulation of tight junction protein ZO-1 (TJP1) were significantly associated with shorter RFS as well as OS. Increased levels of TWIST and decreased levels of TJP1 should be predictive markers for poor prognosis in patients with HCC after hepatectomy; those could serve as potential biomarkers for the treatment of HCC. Key Messages: A low level of TJP1 and high level of TWIST expression were prognostic factors predicting HCC after hepatic resection.

FGF3/FGF4 amplification and multiple lung metastases in responders to sorafenib in hepatocellular carcinoma.

UNLABELLED: The response rate to sorafenib in hepatocellular carcinoma (HCC) is relatively low (0.7%-3%), however, rapid and drastic tumor regression is occasionally observed. The molecular backgrounds and clinico-pathological features of these responders remain largely unclear. We analyzed the clinical and molecular backgrounds of 13 responders to sorafenib with significant tumor shrinkage in a retrospective study. A comparative genomic hybridization analysis using one frozen HCC sample from a responder demonstrated that the 11q13 region, a rare amplicon in HCC including the loci for FGF3 and FGF4, was highly amplified. A real-time polymerase chain reaction-based copy number assay revealed that FGF3/FGF4 amplification was observed in three of the 10 HCC samples from responders in which DNA was evaluable, whereas amplification was not observed in 38 patients with stable or progressive disease (P = 0.006). Fluorescence in situ hybridization analysis confirmed FGF3 amplification. In addition, the clinico-pathological features showed that multiple lung metastases (5/13, P = 0.006) and a poorly differentiated histological type (5/13, P = 0.13) were frequently observed in responders. A growth inhibitory assay showed that only one FGF3/FGF4-amplified and three FGFR2-amplified cancer cell lines exhibited hypersensitivity to sorafenib in vitro. Finally, an in vivo study revealed that treatment with a low dose of sorafenib was partially effective for stably and exogenously expressed FGF4 tumors, while being less effective in tumors expressing EGFP or FGF3. CONCLUSION: FGF3/FGF4 amplification was observed in around 2% of HCCs. Although the sample size was relatively small, FGF3/FGF4 amplification, a poorly differentiated histological type, and multiple lung metastases were frequently observed in responders to sorafenib. Our findings may provide a novel insight into the molecular background of HCC and sorafenib responders, warranting further prospective biomarker studies.

Preliminary Effectiveness of an In-Hospital Peer Support Program, Adolescent and Young Adult Hiroba, on Anxiety in Adolescent and Young Adult Patients with Cancer.

Purpose: Adolescent and young adult (AYA) patients with cancer have few opportunities to connect with patients of the same generation while hospitalized. Although anxiety is frequently reported by them, there are no reports on the psychological effectiveness of an in-hospital patient support program based on peer support. This study aimed to evaluate the effectiveness of a program, termed Adolescent and Young Adult Hiroba (AYA Hiroba), for anxiety in AYA patients with cancer. Methods: This single-center, prospective, observational study in 24 AYA patients with cancer was conducted at the National Cancer Center Hospital in Japan. The Hospital Anxiety and Depression Scale-Anxiety (HADS-A) was used to evaluate the primary outcome, anxiety. The Distress Thermometer (DT) was used to evaluate the secondary outcome, distress. The two outcomes were assessed before and after participation in AYA Hiroba. The Net Promoter Score (NPS) was used to evaluate satisfaction after participation in AYA Hiroba. Participants' free-text descriptions of the program were categorized according to similarities and differences. Results: The HADS-A and DT scores were significantly lower after the program than before (p < 0.001), as was the percentage of AYA patients with cancer with high distress (p = 0.04). The NPS was 27, which was lower than the value of 52 obtained in our previous study. Requests and suggestions to improve the program were grouped into three categories: content, facilitation, and online connection environment. Conclusion: This study suggests the preliminary effectiveness of the in-hospital peer support program for anxiety in AYA patients with cancer. The Clinical Trial Registration number: UMIN000045779.

Integrated analysis of whole genome exon array and array-comparative genomic hybridization in gastric and colorectal cancer cells.

Whole genome-scale integrated analyses of exon array and array-comparative genomic hybridization are expected to enable the identification of unknown genetic features of cancer cells. Here, we evaluated this approach in 22 gastric and colorectal cancer cell lines, focusing on protein kinase genes and genes belonging to the cadherin-catenin family. Regarding alternative splicing patterns, several cancer cell lines predominantly expressed isoform 1 of protein kinase A catalytic subunit beta (PRKACB). Paired gastric cancer specimens demonstrated that isoform 1 of PRKACB was a novel cancer-related variant transcript in gastric cancers. In addition, the exon array analysis clearly identified exon 3 or exon 3-4 skipping in catenin beta 1, a short intron insertion with exon 9 skipping in CDH1, and a deletional transcript of CDH13. These abnormal transcripts were shown to have arisen from small genomic deletions. Meanwhile, an integrated analysis of 11 gastric cancer cell lines revealed that four cell lines amplified fibroblast growth factor receptor 2, with truncated forms observed in two of the cell lines. Gene amplification, and not the truncated form, was found to determine the sensitivity to a fibroblast growth factor receptor inhibitor, indicating that our cell line panel might be useful for cell-based evaluations of specific inhibitors. Using an integrated analysis, we identified several abnormal transcripts and genomic alterations in gastric and colorectal cancer cells. Our approach might enable genetic changes to be identified more efficiently, and the present results warrant further investigation using clinical samples and integrated analyses.

Aza-derivatives of resveratrol are potent macrophage migration inhibitory factor inhibitors.

Resveratrol (3, 4', 5-trihydroxy-trans-stilbene), a natural phytoalexin found in grapes and wine, has anti-proliferative activity on human-derived cancer cells. In our study, we used a conventional condensation reaction between aldehydes and amines to provide a number of aza-resveratrol (3, 4', 5-trihydroxy-trans- aza-stilbene) derivatives in an attempt to screen for compounds with resveratrol's action but with increased potency. Aza-resveratrol and its hydroxylated derivative (3, 4, 4', 5-tetrahydroxy-trans- aza-stilbene) showed a more enhanced anti-proliferative effect than resveratrol in an MCF-7 breast carcinoma cell line. To identify the cellular targets of the aza derivatives of resveratrol, we conjugated the latter aza-stilbene compound with epoxy-activated agarose and performed affinity purification. Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, was identified as a major target protein in MCF-7 cell lysates using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS). The aza-resveratrol and its hydroxylated derivative, but not resveratrol, were also found to be potent inhibitors of MIF tautomerase activity, which may be associated with their inhibitory effects on MIF bioactivity for cell growth.

Plasma concentrations of angiogenesis-related molecules in patients with pancreatic cancer.

BACKGROUND: Anti-angiogenic agents are now being clinically evaluated for the treatment of pancreatic cancer and a detailed investigation of the angiogenic profile of pancreatic cancer is needed. The aim of this study was to evaluate the plasma concentrations of angiogenesis-related molecules in patients with pancreatic cancer, compared with those with other diseases. METHODS: Plasma samples obtained from 45 patients with pancreatic cancer were analyzed and compared with those from 9 patients with pancreatitis, 16 patients with benign hepatobiliary diseases and 58 patients with colorectal cancers. The plasma levels of angiogenesis-related molecules including angiopoietin-2, follistatin, granulocyte-colony stimulating factor, hepatocyte growth factor, interleukin-8, leptin, platelet-derived growth factor beta polypeptide, platelet endothelial cell adhesion molecule-1 and vascular endothelial growth factor were determined using an antibody suspension bead arrays system. RESULTS: The plasma levels of all the angiogenesis-related molecules were not increased in patients with pancreatic cancer, compared with those with pancreatitis and benign hepatobiliary diseases, whereas the levels of those with colorectal cancer were markedly increased. The plasma interleukin-8 concentration was significantly elevated in patients with distant metastases and was associated with a poor treatment outcome of chemotherapy in patients with pancreatic cancer. CONCLUSIONS: The plasma levels of angiogenesis-related molecules were not elevated in patients with pancreatic cancer, compared with those with benign diseases or colorectal cancer. The plasma interleukin-8 level may be a novel biomarker for the response to chemotherapy in patients with pancreatic cancer and warrants further prospective study.

What can and cannot be done using a microarray analysis? Treatment stratification and clinical applications in oncology.

Ten years have passed since the emergence of microarray technology. Recent microarray procedures have provided reliable results on all platforms and have enabled highly reproducible gene expression measurements. Thus, nearly all technical matters regarding microarray measurements are thought to have been resolved. Treatment stratification for molecular-targeted drugs can now be achieved based on the presence of somatic mutations, gene amplification, and/or protein overexpression. However, no clinically available biomarkers have been identified for molecular-targeted drugs using microarray analysis. Microarray data as a database for the gene expressions of clinical samples may be a critical issue, especially for the development of molecular-targeted treatments. In addition, microarray analysis during early-phase clinical trials for molecular-targeted drugs is considered to provide critical information, including proof-of-concept and confirmation of the inhibition of the target molecule. Meanwhile, OncotypeDX(®) and MammaPrint(®) assays have been developed to determine the benefits of chemotherapy for breast cancer patients. These multigene-based assays are commercially available and have shown encouraging results for treatment stratification or decision-making for treatment using cytotoxic drugs in clinical settings. During the development of these assays, numerous samples and efforts were required to create a model using multi-center or inter-group investigations. Based on the success of these models, the development of further assays for determining multigene expressions is likely to increase in the future. In the present article, we introduce our data on mutant epidermal growth factor receptor (EGFR) signaling and amplification of fibroblast growth factor receptor 2 (FGFR2) using microarray analysis, and treatment stratification and clinical applications using gene expression profiles for cancer treatments are discussed.

Safety and effectiveness of secukinumab in psoriasis vulgaris and psoriatic arthritis: Real-world evidence in Japan.

Secukinumab, a fully human monoclonal antibody that selectively neutralizes interleukin-17A, has been available for the treatment of moderate to severe psoriasis and psoriatic arthritis since February 2015 in Japan. Because there was a time gap after the previous approval of biologics for psoriatic disease indication, it was suggested that patients to be treated with secukinumab at its launch might have refractory disease symptoms. In order to assess the safety and effectiveness of secukinumab in those patients, a 52-week, open-label, multicenter, observational cohort study was conducted. In total, 306 and 250 patients were included in the safety and effectiveness analysis sets, respectively. Over half of patients had previously received biologics (56.9%). Adverse events, serious adverse events and adverse reactions were reported in 41.2%, 7.2% and 24.2% of patients, respectively. The most commonly reported adverse reactions were oral candidiasis (2.9%), consistent with those reported in clinical studies. In addition, none of the patient characteristics assessed for the effect on safety of secukinumab increased the occurrence of adverse reactions. Psoriasis Area and Severity Index score (mean ± standard deviation) improved from baseline (14.7 ± 12.3) to week 12 (1.78 ± 3.3), which was maintained up to week 24 (1.59 ± 3.0). The proportion of patients with a Dermatology Life Quality Index score of 0/1 improved from baseline (2.2%) to week 12 (64.7%) and sustained up to week 24 (71.4%). In addition to the skin symptoms, improvement was observed in all psoriatic arthritis disease-related assessments. The current study reaffirmed the safety and effectiveness of secukinumab with broader patients than those in the clinical studies.

Bortezomib potentially inhibits cellular growth of vascular endothelial cells through suppression of G2/M transition.

Bortezomib, a selective 26S proteasome inhibitor, has shown clinical benefits against refractory multiple myeloma. The indirect anti-angiogenic activity of bortezomib has been widely recognized; however, the growth-inhibitory mechanism of bortezomib on vascular endothelial cells remains unclear, especially on the cell cycle. Here, we showed that bortezomib (2 nM of the IC(50) value) potently inhibited the cellular growth of human umbilical vascular endothelial cells (HUVECs) via a vascular endothelial growth factor receptor (VEGFR)-independent mechanism resulting in the induction of apoptosis. Bortezomib significantly increased the vascular permeability of HUVECs, whereas a VEGFR-2 tyrosine kinase inhibitor decreased it. Interestingly, a cell cycle analysis using flow cytometry, the immunostaining of phospho-histone H3, and Giemsa staining revealed that bortezomib suppressed the G2/M transition of HUVECs, whereas the mitotic inhibitor paclitaxel induced M-phase accumulation. A further analysis of cell cycle-related proteins revealed that bortezomib increased the expression levels of cyclin B1, the cdc2/cyclin B complex, and the phosphorylation of all T14, Y15, and T161 residues on cdc2. Bortezomib also increased the ubiquitination of cyclin B1 and wee1, but inhibited the kinase activity of the cdc2/cyclin B complex. These protein modifications support the concept that bortezomib suppresses the G2/M transition, rather than causing M-phase arrest. In conclusion, we demonstrated that bortezomib potently inhibits cell growth by suppressing the G2/M transition, modifying G2/M-phase-related cycle regulators, and increasing the vascular permeability of vascular endothelial cells. Our findings reveal a cell cycle-related mode of action and strongly suggest that bortezomib exerts an additional unique vascular disrupting effect as a vascular targeting drug.

Plasma concentrations of VCAM-1 and PAI-1: a predictive biomarker for post-operative recurrence in colorectal cancer.

This prospective study used antibody suspension bead arrays to identify biomarkers capable of predicting post-operative recurrence with distal metastasis in patients with colorectal cancer. One hundred colorectal cancer patients who underwent surgery were enrolled in this study. The median follow-up period was 3.9 years. The pre-operative plasma concentrations of 24 angiogenesis-related molecules were analyzed with regard to the TNM stage and the development of post-operative recurrence. The concentrations of half of the examined molecules (13/24) increased significantly according to the TNM stage (P < 0.05). Meanwhile, a multivariate logistic regression analysis revealed that the concentrations of vascular cell adhesion molecule 1 (VCAM-1) and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in the post-operative recurrence group. The VCAM-1 and PAI-1 model discriminated post-operative recurrence with an area under the curve of 0.82, a sensitivity of 0.75, and a specificity of 0.73. A leave-one-out cross-validation was applied to the model to assess the prediction performance, and the result indicated that the cross-validated error rate was 12.5% (12/96). In conclusion, our results demonstrate that antibody suspension bead arrays are a powerful tool to screen biomarkers in the clinical setting, and the plasma levels of VCAM-1 and PAI-1 together may be a promising biomarker for predicting post-operative recurrence in patients with colorectal cancer.

Synthesis, crystal structure, and characterization of a heterometallic one-dimensional complex with metal-metal bonds.

The quasi-one-dimensional chain [{PtRh(TCM)(2)(NH(3))(2)Cl(2.5)}(2){Pt(2)(PVM)(2)(NH(3))(4)}(2)](n)(PF(6))(6n).2nH(2)O (Chain-2; TCM = Cl(3)CCONH(-), PVM = (t)BuCONH(-)), which consists of Pt and Rh atoms, has been obtained from two dinuclear compounds, [Pt(2)(PVM)(2)(NH(3))(4)](PF(6))(2).H(2)O (1) and [PtRh(TCM)(2)(NH(3))(2)Cl(3)] (2). Single-crystal X-ray analysis showed that the dinuclear compounds stack with metal-metal bonds to form octameric units, Pt-Rh-Pt-Pt-Pt-Pt-Rh-Pt (Pt(6)Rh(2)), that are bridged by the Cl(-) ion to be a quasi-one-dimensional chain. Elemental analysis, X-ray photoelectron spectroscopy, electron paramagnetic resonance (EPR), and magnetic susceptibility measurements showed that Chain-2 has a mixed valency and one unpaired electron per octameric Pt(6)Rh(2) unit. Taking into account the small observed g(av) value (g(av) = 2.01 at room temperature) obtained by EPR measurement and B3LYP density functional theory calculations of the model complex, oxidation states of the octameric unit are postulated to be Pt(3+)-Rh(2.5+)-Pt(2+)-Pt(2+)-Pt(2+)-Pt(2+)-Rh(2.5+)-Pt(3+), where the EPR isotropic signal showed that the unpaired electron resides in the Rh d(xy) orbitals (delta* orbitals in Pt-Rh dinuclear parts) and hops from one Rh atom to another.

Effect of endurance exercise training on oxidative stress in spontaneously hypertensive rats (SHR) after emergence of hypertension.

The purpose of this study is to elucidate the effect of wheel training on oxidative stress maker levels in spontaneous hypertensive rats (SHR). 4-hydroxynonenal and 3-nitrotyrosine levels in the aorta of SHRs were allowed to run for 10 weeks from the age of 15 weeks were measured and compared with those of nonexercised SHRs. The 4-hydroxynonenal and 3-nitrotyrosine levels in the exercised group were significantly lower than those in the nonexercised group. The exercised group showed a significant increase of manganese-containing superoxide dismutase. Endurance exercise showed a possible suppressing effect on the arteriosclerosis development by reducing oxidative stress, even after emergence of hypertension.

Assessment of serum biomarkers in patients with plaque psoriasis on secukinumab.

The molecular basis of interleukin (IL)-17A in driving psoriasis pathogenesis is not fully elucidated yet. To investigate the underlying mechanisms and biomarkers associated with IL-17A and the role in psoriasis pathogenesis, over 30 serum proteins were evaluated in a study assessing the effectiveness and safety of secukinumab, where treatment was directly switched from cyclosporin A to secukinumab. Serum ß-defensin 2 (BD-2) levels rapidly and robustly reduced following secukinumab treatment. BD-2 levels were well-correlated with Psoriasis Area and Severity Index (PASI) score; changes in BD-2 levels preceded change in PASI score. Serum BD-2, an easily measurable protein, can possibly be used as a suitable surrogate biomarker to monitor responses to IL-17A-targeted therapies for psoriasis in clinical practice.

Propranolol Is an Effective Topical and Systemic Treatment Option for Experimental Epidermolysis Bullosa Acquisita.

Propranolol is an ADRB2 blocker that regulates heart muscle contractions, smooth muscle relaxation, and glycogenolysis. In addition, an increasing number of applications in dermatology have been described, most prominently, the use as a first-line treatment for infantile hemangiomas. We here show that propranolol enhances IL-8-induced neutrophil chemotaxis and reduces the release of ROS after immune complex stimulation. To obtain further molecular insights into the modulatory effects of propranolol in activated neutrophils, we performed RNA sequencing of immune complex-stimulated neutrophils in the absence and presence of the drug. We identified the transcriptomic signature of propranolol and demonstrated an ADR2-independent immunomodulatory effect. To determine if the anti-inflammatory transcriptomic signature of propranolol also translates into clinical effects, we next evaluated the impact of propranolol in a prototypical neutrophil-dependent skin disease, specifically, antibody transfer-induced epidermolysis bullosa acquisita in mice. To validate the identified propranolol gene signature obtained in human neutrophils, we analyzed a selection of genes by RT-PCR in mouse epidermolysis bullosa acquisita skin and confirmed TNF, among others, to be differentially regulated by propranolol treatment. Our data clearly indicate that, based on its molecular impact on immune complex-activated neutrophils, propranolol is a potential treatment option for neutrophil-mediated inflammatory skin diseases.

SRPX2 is overexpressed in gastric cancer and promotes cellular migration and adhesion.

SRPX2 (Sushi repeat containing protein, X-linked 2) was first identified as a downstream molecule of the E2A-HLF fusion gene in t(17;19)-positive leukemia cells and the biological function of this gene remains unknown. We found that SRPX2 is overexpressed in gastric cancer and the expression and clinical features showed that high mRNA expression levels were observed in patients with unfavorable outcomes using real-time RT-PCR. The cellular distribution of SRPX2 protein showed the secretion of SRPX2 into extracellular regions and its localization in the cytoplasm. The introduction of the SRPX2 gene into HEK293 cells did not modulate the cellular proliferative activity but did enhance the cellular migration activity, as shown using migration and scratch assays. The conditioned-medium obtained from SRPX2-overexpressing cells increased the cellular migration activity of a gastric cancer cell line, SNU-16. In addition, SRPX2 protein remarkably enhanced the cellular adhesion of SNU-16 and HSC-39 and increased the phosphorylation levels of focal adhesion kinase (FAK), as shown using western blotting, suggesting that SRPX2 enhances cellular migration and adhesion through FAK signaling. In conclusion, the overexpression of SRPX2 enhances cellular migration and adhesion in gastric cancer cells. Here, we report that the biological functions of SRPX2 include cellular migration and adhesion to cancer cells.

Epidermal growth factor receptor lacking C-terminal autophosphorylation sites retains signal transduction and high sensitivity to epidermal growth factor receptor tyrosine kinase inhibitor.

Constitutively active mutations of epidermal growth factor receptor (EGFR) (delE746_A750) activate downstream signals, such as ERK and Akt, through the phosphorylation of tyrosine residues in the C-terminal region of EGFR. These pathways are thought to be important for cellular sensitivity to EGFR tyrosine kinase inhibitors (TKI). To examine the correlation between phosphorylation of the tyrosine residues in the C-terminal region of EGFR and cellular sensitivity to EGFR TKI, we used wild-type (wt) EGFR, as well as the following constructs: delE746_A750 EGFR; delE746_A750 EGFR with substitution of seven tyrosine residues to phenylalanine in the C-terminal region; and delE746_A750 EGFR with a C-terminal truncation at amino acid 980. These constructs were transfected stably into HEK293 cells and designated HEK293/Wt, HEK293/D, HEK293/D7F, and HEK293/D-Tr, respectively. The HEK293/D cells were found to be 100-fold more sensitive to EGFR TKI (AG1478) than HEK293/Wt. Surprisingly, the HEK293/D7F and HEK293/D-Tr cells, transfected with EGFR lacking the C-terminal autophosphorylation sites, retained high sensitivity to EGFR TKI. In these three high-sensitivity cells, the ERK pathway was activated without ligand stimulation, which was inhibited by EGFR TKI. In addition, although EGFR in the HEK293/D7F and HEK293/D-Tr cells lacked significant tyrosine residues for EGFR signal transduction, phosphorylation of Src homology and collagen homology (Shc) was spontaneously activated in these cells. Our results indicate that tyrosine residues in the C-terminal region of EGFR are not required for cellular sensitivity to EGFR TKI, and that an as-yet-unknown signaling pathway of EGFR may exist that is independent of the C-terminal region of EGFR.

EGFR mutation up-regulates EGR1 expression through the ERK pathway.

BACKGROUND: DelE746_A750-type EGFR is a constitutively active type of mutation that enhances EGFR signaling. However, the changes in gene expression that occur in mutant EGFR-harboring cells has not been fully studied. MATERIALS AND METHODS: A gene expression analysis of HEK293 cells transfected with wild-type or mutant EGFR was performed focusing on the significant gene. RESULTS: Early growth response 1 (EGR1), a transcription factor, was the most strongly up-regulated gene in mutant EGFR-transfected cells among the genes examined. An increase in EGR1 expression in the mutant EGFR cells was confirmed using RT-PCR or immunoblotting. The expression was up-regulated by EGF stimulation and down-regulated by EGFR-tyrosine kinase inhibitor. In addition, the MEK inhibitor U0126 inhibited EGR1 expression, while the phosphatidylinositol 3-kinase inhibitor LY294002 did not. CONCLUSION: Mutant EGFR constitutively up-regulates EGR1 through the ERK pathway, and its expression is correlated with EGFR signal activation. Findings provide an insight into a target gene of mutant EGFR and further improve the understanding of the oncogenic properties of EGFR.

N-Glycan fucosylation of epidermal growth factor receptor modulates receptor activity and sensitivity to epidermal growth factor receptor tyrosine kinase inhibitor.

The glycosylation of cell surface proteins is important for cancer biology processes such as cellular proliferation or metastasis. alpha1,6-Fucosyltransferase (FUT8) transfers a fucose residue to n-linked oligosaccharides on glycoproteins. Herein, we study the effect of fucosylation on epidermal growth factor receptor (EGFR) activity and sensitivity to an EGFR-specific tyrosine kinase inhibitor (EGFR-TKI). The increased fucosylation of EGFR significantly promoted EGF-mediated cellular growth, and the decreased fucosylation by stable FUT8 knockdown weakened the growth response in HEK293 cells. The overexpression of FUT8 cells were more sensitive than the control cells to the EGFR-TKI gefitinib, and FUT8 knockdown decreased the sensitivity to gefitinib. Finally, to examine the effects in a human cancer cell line, we constructed stable FUT8 knockdown A549 cells, and found that these cells also decreased EGF-mediated cellular growth and were less sensitive than the control cells to gefitinib. In conclusion, we demonstrated that the modification of EGFR fucosylation affected EGF-mediated cellular growth and sensitivity to gefitinib. Our results provide a novel insight into how the glycosylation status of a receptor may affect the sensitivity of the cell to molecular target agents.

A novel sensitive immunoassay method based on the Invader technique.

A novel and sensitive immunoassay method has been developed in which the conventional sandwich immunoassay and the highly sensitive DNA detection method, the Invader method, are combined. The signal amplification function of the latter method has been successfully used to enhance the sensitivity of the sandwich immunoassay. The new assay method may be called the Immuno-Invader assay. The assay format involves three important steps: (1) a target antigen is captured and flagged with a biotin-conjugated detection antibody by the sandwich method, (2) streptavidin and a biotin-conjugated oligonucleotide are added to form a complex with the detection antibody, and (3) the oligonucleotide in the complex is detected using the Invader method. The method was applied to the assay of human tumor necrosis factor-alpha (hTNF-alpha). Detection limits obtained were 0.1 pg/ml hTNF-alpha when a luminescent europium chelate was used with a time-resolved measurement mode, and 0.8 pg/ml when fluorescein was used with a normal prompt fluorescence measurement mode. On the other hand, the detection limit of a commercially available hTNF-alpha enzyme-linked immunosorbent assay that uses horseradish peroxidase was 3.5 pg/ml. These results demonstrate the feasibility and potential of the new assay method for highly sensitive immunoassay.