The Impact of c-Fos/Activator Protein-1 Inhibition on Allogeneic Pancreatic Islet Transplantation.

Unpreventable allograft rejection is one of the main problems in pancreatic islet transplantation (PIT). Therefore, it is imperative to develop a more effective immunosuppressive strategy. The blockade of transcription factors has been a central part of T cell-depleting immunosuppressive therapies, as typified by the use of calcineurin inhibitors. The inhibition of activator protein-1 (AP-1) offers a novel strategy for immunosuppression in PIT, although to date, no reports on the effects of AP-1 inhibition are available. In this study, we investigated the immunosuppressive effects of T-5224, a c-Fos/AP-1-selective inhibitor, on murine T cells activated by αCD3+αCD28 mAbs. T-5224 inhibited proliferation, CD25 up-regulation, and the production of IL-2 and interferon-γ. In addition, T-5224 blocked the nuclear translocation of c-Fos/AP-1 in activated murine T cells. In BALB/c (H-2(d) )-to-C57BL/6J (H-2(b) ) mouse PIT, the 2-week administration of T-5224 prolonged survival of 600 islet allografts in a dose-dependent manner. When combined with a 2-week low-dose tacrolimus, the T-5224 treatment markedly prolonged allograft survival to over 300 days, while the efficacy was indeterminate when transplanted islet allograft mass was reduced to 300. We conclude that the c-Fos/AP-1 inhibition by T-5224 is a potentially attractive strategy for allogeneic PIT.

Clinicopathological features of nonsmall cell lung carcinomas with BRAF mutations.

BACKGROUND: Recently, driver tyrosine kinase gene mutations have been detected in malignant tumors, including lung tumors. Notwithstanding their attractiveness as targets for molecular therapy, limited information is available regarding BRAF-mutated lung carcinomas. MATERIALS AND METHODS: BRAF mutation status was determined in 2001 surgically resected nonsmall-cell lung cancer (NSCLC) cases using high-resolution melting analysis (HRMA) followed by Sanger sequencing and/or deep sequencing using next generation sequencer. RESULTS: BRAF mutations were detected in 26 (1.3%) of 2001 NSCLC cases (25 adenocarcinomas and 1 squamous cell carcinoma). In the 26 cases, 13 mutation genotypes were identified, including V600E (8 of 26; 30.8%), G469A (6 of 26; 23.1%), K601E (4 of 26; 15.4%), and other residual mutations (1 of 26; 0.04%). Of the 13 genotypes, 4 genotypes (G464E, G596R, A598T, and G606R) had not been previously reported in lung cancer. The overall survival rate was not significantly different between patients with wild-type BRAF and those with V600E or non-V600E BRAF mutations (P = 0.49 and P = 0.15, respectively). Histomorphological analysis revealed that focal clear cell changes were present in 75% of V600E-mutated tumors. All V600E BRAF-mutated tumors were negative for other driver gene alterations including epidermal growth factor receptor (EGFR) and KRAS mutations and the anaplastic lymphoma kinase gene translocation, whereas five tumors with non-V600E BRAF mutations (four G469A and one G464E/G466R) showed concomitant EGFR mutations. CONCLUSION: The frequency of BRAF mutations in lung cancer was low in an Asian cohort. Furthermore, BRAF mutation status lacked prognostic significance in this patient population.

A health-risk appraisal model and endoscopic mass screening for esophageal cancer in Japanese men.

A strong association between inactive aldehyde dehydrogenase-2 (ALDH2) and risk of esophageal cancer has been demonstrated in East Asian drinkers. An alcohol flushing questionnaire asking about past and current tendency for facial flushing to occur after drinking a glass (≈180 mL) of beer predicts the presence of inactive ALDH2 among Japanese aged 40 years or older with a sensitivity and specificity of approximately 90%. We invented a health-risk appraisal (HRA) model that makes it possible to identify Japanese men who are at high risk for esophageal cancer based on their past and current alcohol flushing tendency, drinking, smoking, and intake of vegetables and fruits. Between 2008 and 2009, 2221 Japanese men aged 50 years or older filled out the HRA questionnaire before undergoing a screening examination by upper gastrointestinal endoscopy at five medical facilities. The endoscopic examination resulted in a diagnosis of esophageal cancer in 19 subjects, and 117 (5.27%) subjects had an HRA score ≥ 11. The proportion of subjects with an HRA score ≥ 11 was higher in the 50-69 age group (6.11-6.88%) than in 70-89 age group (2.84-2.86%). The esophageal cancer detection rate was 4.27% among the subjects with an HRA score ≥ 11 and only 0.67% among the other subjects. Based on a receiver operating characteristic curve analysis, when an HRA score of ≥ 9 was used for subjects aged 50-69 years and of ≥ 8 for those aged 70-89 years as the cutoff value to select individuals with a high risk for esophageal cancer, its sensitivity and false-positive rate was 52.6% and 15.2%, respectively, and the cancer detection rate was 2.91% in the high-risk group, as opposed to 0.48% in the other group. In conclusion, the high detection rates for esophageal cancer in the high-risk groups encouraged screening based on our HRA model in larger Japanese populations.

Chemotherapy after nivolumab for advanced gastric cancer (REVIVE): a prospective observational study.

BACKGROUND: Nivolumab therapy is a standard-of-care treatment for heavily pretreated patients with advanced gastric cancer (AGC). Previous studies have reported improvement in the objective response rate to chemotherapy after nivolumab therapy for other types of cancer. This study evaluated the efficacy and safety of chemotherapy after nivolumab therapy in AGC. PATIENTS AND METHODS: We conducted a prospective, multicenter, observational study in pretreated patients with nivolumab-refractory or -intolerant AGC. Patients received irinotecan, oxaliplatin-containing regimens, or trifluridine/tipiracil. The primary endpoint was overall survival. RESULTS: A total of 199 patients were included (median age: 69 years; male: 70%; female: 30%). Median overall survival and progression-free survival were 7.5 months [95% confidence interval (CI): 6.7-9.7 months] and 2.9 months (95% CI: 2.2-3.5 months), respectively. Objective response and disease control rates were 16.8% (95% CI: 11.6% to 23.6%) and 18.9% (95% CI: 38.9% to 54.6%), respectively. A prognostic index using alkaline phosphatase and the Glasgow Prognostic Score was generated to classify patients into three risk groups (good, moderate, and poor). The hazard ratios of the moderate and poor groups to the good group were 1.88 (95% CI: 1.22-2.92) and 3.29 (95% CI: 1.92-5.63), respectively. At the initiation of chemotherapy, 42 patients had experienced immune-related adverse events due to prior nivolumab therapy. The most common grade 3-4 adverse events were neutropenia (7.5%), anemia (8.0%), and anorexia (7.5%). CONCLUSIONS: The administration of cytotoxic chemotherapy after nivolumab therapy may give rise to a synergistic antitumor effect in AGC. Further investigation is warranted to confirm these findings.

Tongue surface model can predict radiation tongue mucositis due to intensity-modulated radiation therapy for head and neck cancer.

Acute radiation tongue mucositis has a profound effect on talking and eating. We examined whether the dose-volume histogram obtained from the tongue surface model correlates with mucositis severity, and whether it is useful for predicting acute radiation tongue mucositis in patients with head and neck cancer treated with intensity-modulated radiation therapy. Thirty-six patients who received intensity-modulated radiation therapy for head and neck cancer were analysed for acute radiation tongue mucositis according to the Common Terminology Criteria for Adverse Events, version 4.0, as well as the Radiation Therapy Oncology Group scoring systems. The corresponding high-dose locations in anatomical sub-regions in the tongue surface model and the development of high-grade acute radiation tongue mucositis were compared. The mucositis sites coincided with the high-dose anatomical sub-regions in the tongue surface model. There was a clear dose-response relationship between the mean dose to the tongue and the acute radiation tongue mucositis Radiation Therapy Oncology Group grade. According to the dose-volume histogram, patients receiving 16.0-73.0 Gy to the tongue were susceptible to grade 2-3 toxicity. The tongue surface model can predict the site and severity of acute radiation tongue mucositis. In future, radiation treatment plans ccould be optimized using this model.

Ecology of the cardiovascular system: Part II - A focus on non-air related pollutants.

An integrated exposomic view of the relation between environment and cardiovascular health should consider the effects of both air and non-air related environmental stressors. Cardiovascular impacts of ambient air temperature, indoor and outdoor air pollution were recently reviewed. We aim, in this second part, to address the cardiovascular effects of noise, food pollutants, radiation, and some other emerging environmental factors. Road traffic noise exposure is associated with increased risk of premature arteriosclerosis, coronary artery disease, and stroke. Numerous studies report an increased prevalence of hypertension in people exposed to noise, especially while sleeping. Sleep disturbances generated by nocturnal noise are followed by a neuroendocrine stress response. Some oxidative and inflammatory endothelial reactions are observed during experimental session of noise exposure. Moreover, throughout the alimentation, the cardiovascular system is exposed to persistent organic pollutants (POPs) as dioxins or pesticides, and plastic associated chemicals (PACs), such as bisphenol A. Epidemiological studies show positive associations of exposures to POPs and PACs with diabetes, arteriosclerosis and cardiovascular disease incidence. POPs and PACS share some abilities to interact with nuclear receptors activating different pathways leading to oxidative stress, insulin resistance and angiotensin potentiation. Regarding radiation, survivors of nuclear explosion have an excess risk of cardiovascular disease. Dose-effect relationships remain debated, but an increased cardiovascular risk at low dose of radiation exposure may be of concern. Some emerging environmental factors like electromagnetic fields, greenspace and light exposure may also require further attention. Non-air related environmental stressors also play an important role in the burden of cardiovascular disease. Specific methodologies should be developed to assess the interactions between air and non-air related pollutants.

Characterization of a duocarmycin-DNA adduct-recognizing protein in cancer cells.

Duocarmycins have been reported to derive their potent antitumor activity through a sequence-selective minor groove alkylation of N3 adenine in double-stranded DNA. We have used gel mobility shift assays to detect proteins that bind to DNA treated in vitro with duocarmycin SA and identified a protein, named duocarmycin-DNA adduct recognizing protein (DARP), which binds with increased affinity to duocarmycin-damaged DNA. Examination with partially purified DARP revealed that the protein recognized not only the DNA adduct of structurally related drug, CC-1065, but unexpectedly, the protein also recognized the DNA adduct of another chemotype of minor groove binder, anthramycin. These results demonstrate that DARP recognizes the structural alteration of DNA induced by these potent DNA-alkylating drugs, suggesting the possibility that the protein might modulate the antitumor activity of these drugs.

G1 phase accumulation induced by UCN-01 is associated with dephosphorylation of Rb and CDK2 proteins as well as induction of CDK inhibitor p21/Cip1/WAF1/Sdi1 in p53-mutated human epidermoid carcinoma A431 cells.

UCN-01 (7-hydroxyl-staurosporine) was originally isolated as a Ca2+- and phospholipid-dependent protein kinase C selective inhibitor and now is being developed as an anticancer agent. Results from our and other laboratories have suggested that UCN-01 induces preferential G1-phase accumulation in several human tumor cell lines tested. To elucidate this mechanism, we examined the effects of UCN-01 on several cell cycle-regulatory proteins critical for G1-S-phase transition in p53-mutated human epidermoid carcinoma A431 cells. After 24 h exposure at around 50% growth-inhibitory concentrations (IC50s), 260 and 520 nM, UCN-01 induced the accumulation of pRb (the dephosphorylated retinoblastoma protein form). The protein expression of cyclin A but not cyclin E was markedly reduced and that of cyclin D1 was partially reduced under the same condition. UCN-01 also showed the concentration-dependent inhibitions of the activity of cyclin-dependent kinase 2 (CDK2) using histone H1 and pRb as substrates in vitro (IC50, 530 and 640 nM, respectively). In addition, CDK2 activities of the cells pretreated with UCN-01 for 24 h at 260 and 520 nM were markedly inhibited, giving IC50s of far less than 260 nM. When the same cell lysates were analyzed by Western blotting for CDK2, the lower band (e.g., active and phosphorylated CDK2) was remarkably reduced, in accordance with the reduced activity. Furthermore, UCN-01 induced the expression of the CDK inhibitor p21 protein and its complex formation with CDK2 after 24 h exposure at 260 and 520 nM, whereas the expression level was very low or undetectable in untreated or DNA-damaged cells. The increase of p21 mRNA levels was also induced under the same condition. UCN-01 further increased luciferase activities in A431 cells transiently transfected with p21 promoter-luciferase reporter plasmid after 24 h exposure at 260 and 520 nM. UCN-01 also increased the expression of the CDK inhibitor p27 protein after 24 h exposure at 260 and 520 nM. These results suggest that G1-phase accumulation induced by UCN-01 is associated with dephosphorylation of Rb and CDK2 proteins as well as induction of CDK inhibitors p21 and p27.

The stabilization mechanism of mutant-type p53 by impaired ubiquitination: the loss of wild-type p53 function and the hsp90 association.

Mutant-type p53 (mt p53) is largely accumulated in cancer cells due to its increased stability. To elucidate the mechanism of mt p53 stabilization, we analysed the turnover of p53 mutated at codon 248 whose alteration is most frequently found in human cancers. Proteasome inhibition induced the accumulation of ubiquitinated mt p53, indicating that the ubiquitinated forms were essentially unstable and degraded by the proteasome. The presence of a small amount of the ubiquitinated mt p53 relative to the abundant non-ubiquitinated form suggested that the mt p53 ubiquitination was a rate-limiting process in the slow turnover. Two phenomena destabilizing mt p53 via the ubiquitin-proteasome degradation were proved to be independent. First, the coexpression of wild-type p53 (wt p53) promoted mt p53 destabilization as feedback regulation. Second, geldanamycin also induced mt p53 destabilization through the dissociation of the protein from hsp90 but not through the restoration of wt p53 function. Neither the mutant-specific conformation nor the N-terminal phosphorylation seemed to contribute directly to the mt p53 stabilization. Further, a two-dimensional gel electrophoresis revealed that most of the post-translationally modified mt p53 was equally subjected to ubiquitination and subsequent proteasomal degradation. These findings are evidence that mt p53 stabilization depends on the impaired ubiquitination due to both the loss of wt p53 function and the hsp90 association.

Isolation and characterization of a novel growth hormone cDNA from chum salmon (Oncorhynchus keta).

A cDNA clone which codes for a novel growth hormone has been isolated from the library of chum salmon pituitaries. The clone encodes a polypeptide of 210 amino-acid residues including 22 amino-acid residues of signal peptide, which is identical in length with known chum salmon growth hormone. In the coding region, there are 30 base substitutions, some of which result in 12 amino-acid substitutions. There are 8 base changes in the 5' untranslated region, and large insertions/deletions are in the 3' non-coding region. These results clearly indicate that there are at least two species of mRNAs for growth hormone in chum salmon pituitary.

A physical map of the genome of the Bacillus subtilis temperate phage rho 11.

A cleavage map of Bacillus subtilis temperate phage rho 11 was constructed with restriction endonucleases SalI, BamHI and BglII, which cut the genome into 6, 7 and 21 fragments, respectively. The molecular weight of the rho 11 genome was calculated to be 78 x 10(6). Among other endonucleases tested, PvuII, EcoRI and XbaI cleaved the genome into more than 25 fragments, while HaeIII, StuI, BalI and BamNx did not cut the genome at all. The rho 11-coded thymidylate synthetase gene, thyP11, was found to be located in the SalI-D fragment, which was in the central region of the genome.

A new SV40-based vector developed for cDNA expression in animal cells.

A useful vector, pAGE103, has been developed for the expression of cDNA in animal cells using the simian virus 40 (SV40) expression signals. cDNA could be expressed easily by inserting it into the multiple cloning sites (HindIII, SalI/AccI, XbaI, BamHI, SmaI/XmaI, KpnI/Asp718, SacI and EcoRI) of the vector, which are located between the SV40 early promoter and the SV40 early RNA processing signals for splicing and polyadenylation. In addition to the above transcription unit, pAGE103 contains the replication origin of ColE1, and a dual KmR/G418R selective gene. Several unique restriction sites are located on the boundaries between the above-mentioned three components of the vector, allowing the easy substitution or insertion of other genetic elements. The human interferon-beta gene was inserted into pAGE103 and shown to be expressed transiently in COS-1 cells and stably in several animal cell lines.

Studies on the substrate specificity of Taka-amylase A. XIII. Preparation of 6-deoxy-6-iodomaltooligosaccharides and their inhibitory action against Taka-amylase A1.

O-alpha-D-Glucopyranosyl-(1 leads to 4)-O-6-deoxy-6-iodo-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose (6'-MT), O-alpha-D-glucopyranosyl-(1 leads to 4)-6-deoxy-6-iodo-D-glucopyranose (6-M), and O-6-deoxy-6-iodo-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose (6'-M) were prepared and their inhibitory action against Taka-amylase A [EC 3.2.1.1, alpha-1, 4-glucan 4-glucanohydrolase, Aspergillus oryzae] was investigated. The inhibitor constants of 6'-MT and 6'-M were 10 mM and 54 mM, respectively, and both inhibitors showed mixed-type inhibition. 6-M scarcely inhibited the enzyme action.

Studies of the action pattern of an alpha-amylase from Streptomyces praecox NA-273.

An alpha-amylase [EC 3.2.1.1] from Streptomyces praecox was purified and its characteristic action, the conversion of maltotriose (G3) to maltose (G2) without appreciable formation of glucose (G1), was investigated. Isoelectric focusing or the glycogen adsorption procedure was employed after chromatography. Isoelectric focusing showed that the enzyme preparation after chromatographic separation comprises three isozymes. The preparation from the glycogen adsorption procedure showed the highest specific activity of any preparation of this enzyme ever obtained. Product analysis with uniformly labeled G3 revealed that at a high concentration (18 mM) of G3, much more G2 is produced than G1 (the product ratio G2/G1 is over 20), while at a lower concentration (10 microM) the reaction mixture was composed of nearly equimolar amounts of glucose and maltose. Based on the product analysis of reducing end-labeled G3 in addition to the above findings, the following conversion mechanism is proposed: Streptomyces alpha-amylase catalyzes transglycosylation to produce maltotetraose (G4) as a transient product which is immediately degraded into two molecules of G2 by a subsequent hydrolytic reaction, i.e., two molecules of G3 are converted into three molecules of maltose without appreciable formation of glucose.

Primary hypothyroidism and multiple endocrine failure in association with hemochromatosis in a long-term hemodialysis patient.

A 56-year-old male patient on chronic hemodialysis developed liver cirrhosis. He received a total of 20 liters of blood transfusion. Bronze pigmentation of the skin and iron deposition to the liver, spleen, pancreas and thyroid gland, which was demonstrated by computed tomography and magnetic resonance imaging studies, and histological demonstration of iron deposition to the thyroid gland, bone marrow and gastric mucosa established a diagnosis of secondary hemochromatosis. Endocrine work-up revealed the presence of diabetes mellitus with minimum insulin secretory response, primary (or thyroprivic) hypothyroidism, hypoparathyroidism and hypogonadotropic hypogonadism. A wide-spread endocrine involvement as seen in this patient is a rare clinical feature of hemochromatosis secondary to massive blood transfusion in hemodialysis patients. Particularly, primary hypothyroidism due to iron deposition to the thyroid gland was quite a rare feature of hemochromatosis.