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Human head and neck squamous cell carcinoma cells transfected with mutant TP53 (SAS/mp53) or neo vector (SAS/neo) were inoculated subcutaneously into left hind legs of nude mice. After the subcutaneous administration of a 10B-carrier, boronophenylalanine-10B (BPA) or sodium mercaptododecaborate-10B (BSH), at two separate concentrations, the 10B concentrations in tumors were measured using γ-ray spectrometry. The tumor-bearing mice received 5-bromo-2’-deoxyuridine (BrdU) continuously to label all intratumor proliferating (P) tumor cells, then were administered with BPA or BSH. Subsequently, the tumors were irradiated with reactor neutron beams during the time of which 10B concentrations were kept at levels similar to each other. Following irradiation, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of BrdU-unlabeled quiescent (Q) and total (= P + Q) tumor cells were assessed based on the frequencies of micronucleation using immunofluorescence staining for BrdU. In both SAS/neo and SAS/mp53 tumors, the compound biological effectiveness (CBE) values were higher in Q cells and in the use of BPA than total cells and BSH, respectively. The higher the administered concentrations were, the smaller the CBE values became, with a clearer tendency in SAS/neo tumors and the use of BPA than in SAS/mp53 tumors and BSH, respectively. The values for BPA that delivers into solid tumors more dependently on uptake capacity of tumor cells than BSH became more alterable. Tumor micro-environmental heterogeneity might partially influence on the CBE value. The CBE value can be regarded as one of the indices showing the level of intratumor heterogeneity.

Boron neutron capture therapy (BNCT) is a radiation therapy for cancer. In BNCT, the internalization of boron-10 atoms by cancer cells induces cell death through the generation of α particles and recoiling lithium-7 nuclei when irradiated with low-energy thermal neutrons. In this study, we aimed to construct exosomes [extracellular vesicles (EVs)]-based drug delivery technology in BNCT. Because of their pharmaceutical advantages, such as controlled immune responses and effective usage of cell-to-cell communication, EVs are potential next-generation drug delivery carriers. In this study, we successfully developed polyhedral borane anion-encapsulated EVs with modification of hexadeca oligoarginine, which is a cell-penetrating peptide, on the EV membrane to induce the actin-dependent endocytosis pathway, macropinocytosis, which leads to efficient cellular uptake and remarkable cancer cell-killing BNCT activity. The simple and innovative technology of the EV-based delivery system with "cassette" modification of functional peptides will be applicable not only for BNCT but also for a wide variety of therapeutic methodologies.

BACKGROUND: Colon cancer is still a crucial concern in the development of chemotherapeutic drugs due to the drug resistance phenomenon and various side effects to patients. One of the newest compound that show anticancer activities against several cancer cells, Chemoprevention Curcumin Analog 1 (CCA-1.1), has increasingly been explored to overcome the limitation of conventional drugs. METHODS: We evaluated the anti-migratory effect of CCA-1.1 and Pentagamavunone-1 (PGV-1) by using WiDr colon cancer cells. The expression profiles of Tumor Protein 53 (TP53) and Matrix Metalloproteinase-9 (MMP9) in colon cancer were obtained from the UALCAN database. Survival outcomes of TP53 and MMP9 in colon cancer patients were analyzed using the Kaplan-Meier method. We used 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT), scratch wound healing, and gelatin zymography assays to observe the cytotoxic effect, anti-migratory activity, and MMP9 expression, respectively, in CCA-1.1 or PGV-1-treated cells. RESULTS: Level of MMP9 was found significantly overexpressed in the primary tumor and metastasis nodal, while TP53 mutation sample types were observed and influenced the survival outcome in colon cancer patients. CCA-1.1 and PGV-1 exhibited strong cytotoxic activity after 24 and 48 h treatment against WiDr cells. The migration assay demonstrated that PGV-1 and CCA-1.1 at 1 mM inhibited cell migration up to 40% after 48 h in single and combination with doxorubicin. The MMP9 expression was significantly inhibited by 0.5 mM CCA-1.1. CONCLUSION: This study emphasizes that the anti-migratory effect of CCA-1.1 is better than PGV-1 via MMP9 suppression on WiDr. Thus, CCA-1.1 is prominent to be developed as an anti-metastatic agent. KEYWORDS: chemopreventive curcumin analog 1.1 (CCA-1.1), PGV-1, WiDr cells, anti-migration, MMP9

Background: Boron neutron capture therapy (BNCT) has been adapted to high-grade gliomas (HG); however, some gliomas are refractory to BNCT using boronophenylalanine (BPA). In this study, the feasibility of BNCT targeting the 18 kDa translocator protein (TSPO) expressed in glioblastoma and surrounding environmental cells was investigated. Methods: Three rat glioma cell lines, an F98 rat glioma bearing brain tumor model, DPA-BSTPG which is a boron-10 compound targeting TSPO, BPA, and sodium borocaptate (BSH) were used. TSPO expression was evaluated in the F98 rat glioma model. Boron uptake was assessed in three rat glioma cell lines and in the F98 rat glioma model. In vitro and in vivo neutron irradiation experiments were performed. Results: DPA-BSTPG was efficiently taken up in vitro. The brain tumor has 16-fold higher TSPO expressions than its brain tissue. The compound biological effectiveness value of DPA-BSTPG was 8.43 to F98 rat glioma cells. The boron concentration in the tumor using DPA-BSTPG convection-enhanced delivery (CED) administration was approximately twice as high as using BPA intravenous administration. BNCT using DPA-BSTPG has significant efficacy over the untreated group. BNCT using a combination of BPA and DPA-BSTPG gained significantly longer survival times than using BPA alone. Conclusion: DPA-BSTPG in combination with BPA may provide the multi-targeted neutron capture therapy against HG.

Objective: The progress from Boron Neutron Capture Therapy (BNCT) development urged us to explore new targeted and selective boron carriers. Firstly, we reported the successful synthesis of CCB-2 which exerts a cytotoxic effect against triple negative breast cancer (TNBC) cells. We introduced the new modification of CCB-2 with sugar and alcohol sugars to enhance its solubility in hoping to increase cellular uptake. Methods: CCB-2 fructose complex (CCB-2-F), CCB-2 sorbitol complex (CCB-2-Sor), and CCB-2 xylitol complex (CCB-2-Xy) were obtained with small size within nano-specific particle. All the compounds were then determined for their cytotoxic activities through MTT assay. Results: All compounds were performed cytotoxic activities against TNBC 4T1 and HER-2 positive MCF-7/HER2 cells with good selectivity when tested in immortalized fibroblast cells. Conclusion: Overall, we provided a new modification of CCB-2 through complexation with sugars. Still, further evaluations are needed to develop more efficient CCB-2 as the new candidate of anticancer agent, notably in breast cancer.

An improved compound of pentagamavunone-1 (PGV-1), chemoprevention-curcumin analog 1.1 (CCA-1.1), has been synthesized and proven to have antiproliferative effects against breast cancer cells. This study is designed to investigate the potency of CCA-1.1 alone and in combination with doxorubicin (Dox) on T47D cells in comparison with that of PGV-1. We used the MTT assay to assess cytotoxic activity. Propidium iodide (PI), annexin-V–PI, and DCFDA staining were respectively used to determine cell cycle profiles, apoptosis, and intracellular reactive oxygen species (ROS) levels. Senescent cells were identified using the SA-b-galactosidase assay. Our results revealed that CCA-1.1 possesses cytotoxic effects similar to those of PGV-1 on T47D cells. Synergistic effects during co-treatment with Dox were also observed. CCA-1.1 arrested cell cycle progression at the G2/M phase and limited sub-G1 accumulation, which is correlated with apoptosis. CCA-1.1 alone and in combination with Dox increased senescence and intracellular ROS to a similar level to those achieved by PGV-1. CCA-1.1 alone and in combination with Dox enhanced cytotoxic activity toward T47 cells compared to PGV-1. Thus, this curcumin analog may be a potential chemotherapeutic/co-chemotherapeutic candidate for estrogen receptor-positive (ER+) breast cancer therapy.

[Image: see text] We developed novel closo-dodecaborate ([B(12)H(11)](2–)) anion-containing translocator protein (TSPO) ligand as a boron carrier for boron neutron capture therapy. This compound shows high water solubility and can deliver boron to TSPO highly expressed in breast cancer cells. We describe the synthesis and in vitro evaluation of a dodecaborate-based pyrazolopyrimidine.

Pentagamavunone-1 and its newest derivatives, CCA-1.1, possess an outstanding cytotoxic activity against several cancer cell lines, especially colorectal cancer. We are continuing to explore the anti-colorectal cancer properties of PGV-1 and CCA-1.1 against DMH-induced colorectal cancer rats and expound the potential protein target in colorectal adenocarcinoma. We utilized DMH 60 mg/kg (subcutaneous injection once a week for 16 weeks) to induce colorectal cancer. PGV-1 and CCA-1.1 at 10 and 20 mg/kg (orally twice a week for 16 weeks) were co-administered with DMH. The WBC count increased in a single DMH group and was countered by co-administration of PGV-1 and CCA-1.1, but no significant differences in RBC. Single DMH treatment for 16 weeks resulted in 80% adenocarcinoma. In contrast, co-administration with PGV-1 and CCA-1.1 suppressed most of the carcinogenic characteristics and symptoms of the pre-malignancy condition. Furthermore, bioinformatics analysis showed that CCA-1.1 has more specific targets than PGV-1, including CDK1, CDK2, MMP3, MMP14, and CYP3A4, which regulate the cell cycle arrest, cancer cell migration, and xenobiotic metabolism, respectively. Interestingly, CCA-1.1 targets CYP3A4, which possibly interrupts DMH metabolism and prevents the initiation of DMH-colorectal carcinogenesis. In conclusion, CCA-1.1 performed better chemopreventive effects against DMH colorectal cancer and might replace PGV-1 to be promoted as a more effective anti-colorectal cancer agent.

Boronic acid-containing curcumin analog, pentagamaboronon-0 (PGB-0), acts as a potential boron-carrier agent but has limited water solubility. Thus, a new compound (PGB-0-ol) with better chemical and pharmacological properties than PGB-0 has been synthesized. Molecular docking was performed using a molecular operating environment. Prediction of PGB-0-ol absorption, distribution, metabolism, and excretion (ADME) was performed using pkCSM software. PGB-0-ol was synthesized by adding NaBH4 to PGB-0 and stirring for 1 h. The crude PGB-0-ol was purified using preparative layer chromatography. Cell viability was evaluated using the trypan blue exclusion assay. In comparison to PGB-0 based on molecular docking study, PGB-0-ol could interact in with several cancer biomarkers, such as human epidermal growth factor2 epidermal growth factor receptor, IκB kinase, folate receptor-α, and integrin αvβ3. PGB-0-ol also showed an improved ADME profile because of its higher water solubility than PGB-0. PGB-0-ol was synthesized by selective ketone reduction of PGB-0 into primary alcohol by sodium borohydrate producing 30% yield. The cytotoxicity of PGB-0-ol against several breast cancer cells was lower than that of PGB-0. The novel compound PGB-0-ol was synthesized using simple steps. PGB-0-ol has low cytotoxicity against breast cancer cells and could be applied in boron neutron capture therapy as a boron carrier.

Homocereulide, isolated from marine bacterium Bacillus cereus, is an analog of emetic toxin cereulide. There is no report on its structure determination and involvement in B. cereus-associated food poisoning. Homocereulide is a cyclic dodecadepsipeptide composed of l -O-Val- l -Val- d -O-Leu- d -Ala and l -O-allo-Ile- d -Val- d -O-Leu- d -Ala. Here, we synthesized homocereulide using liquid phase fragment condensation. The NMR spectrum of synthesized homocereulide confirmed the intended structure and LC-MS results were consistent with natural products. Morphological evaluation using HEp-2 cells showed higher toxicity with homocereulide (1.39 nM) than cereulide (3.95 nM). Though cereulide is the main component in broth culture, homocereulide is also likely involved in B. cereus-associated food poisoning.

Background: The development of effective boron compounds is a major area of research in the study of boron neutron capture therapy (BNCT). We created a novel boron compound, boronophenylalanine&ndash, amide alkyl dodecaborate (BADB), for application in BNCT and focused on elucidating how it affected a rat brain tumor model. Methods: The boron concentration of F98 rat glioma cells following exposure to boronophenylalanine (BPA) (which is currently being utilized clinically) and BADB was evaluated, and the biodistributions in F98 glioma-bearing rats were assessed. In neutron irradiation studies, the in vitro cytotoxicity of each boron compound and the in vivo corresponding therapeutic effect were evaluated in terms of survival time. Results: The survival fractions of the groups irradiated with BPA and BADB were not significantly different. BADB administered for 6 h after the termination of convection-enhanced delivery ensured the highest boron concentration in the tumor (45.8 &mu, g B/g). The median survival time in the BADB in combination with BPA group showed a more significant prolongation of survival than that of the BPA group. Conclusion: BADB is a novel boron compound for BNCT that triggers a prolonged survival effect in patients receiving BNCT.

Boron neutron capture therapy (BNCT) is a form of tumor-cell selective particle irradiation using low-energy neutron irradiation of boron-10 (10B) to produce high-linear energy transfer (LET) alpha particles and recoiling 7Li nuclei (10B [n, alpha] 7Li) in tumor cells. Therefore, it is important to achieve the selective delivery of large amounts of 10B to tumor cells, with only small amounts of 10B to normal tissues. To develop practical materials utilizing 10B carriers, we designed and synthesized novel dodecaboranethiol (BSH)-containing kojic acid (KA-BSH). In the present study, we evaluated the effects of this novel 10B carrier on cytotoxicity, 10B concentrations in F98 rat glioma cells, and micro-distribution of KA-BSH in vitro. Furthermore, biodistribution studies were performed in a rat brain tumor model. The tumor boron concentrations showed the highest concentrations at 1 h after the termination of administration. Based on these results, neutron irradiation was evaluated at the Kyoto University Research Reactor Institute (KURRI) with KA-BSH. Median survival times (MSTs) of untreated and irradiated control rats were 29.5 and 30.5 days, respectively, while animals that received KA-BSH, followed by neutron irradiation, had an MST of 36.0 days (p = 0.0027, 0.0053). Based on these findings, further studies are warranted in using KA-BSH as a new B compound for malignant glioma.

Boronic acid containing compounds are regarded as a new class of pharmaceuticals, and the distribution in live cells is crucial for the development of novel drugs. However, generic detection methods for boron compounds are not suitable for live-cell imaging, and the fluorescence-labeling technique is challenging to apply for small molecules. Fluorescent boron-sensor DAHMI which is based on a boron chelating ligand was developed for a novel visualization method of boron-based pharmaceuticals in the live cell. In this study, we analyzed the distribution of boronic acid derivatives in live cells using a fluorescent boronic acid sensor.

Development of specific and selective boron carriers is indispensable for boron neutron capture therapy (BNCT) application. Pentagamaboronon-0 (PGB-0) is a promising candidate as boron carrier compound due to the low but selective cytotoxicity in breast cancer cells. Formerly we reported synthesis of PGB-0 which was ineffective due to its low aqueous solubility. In the present study, we, therefore, introduced the new PGB-0 preparation complexed with sugars to increase its solubility in water. By synthesizing at room temperature and using flash chromatography for the purification, we produced PGB-0 with a yield of 40%. PGB-0 fructose complex (PGB-0-F) and PGB-0 sorbitol complex (PGB-0-Sor) were obtained with smaller particle size compared to PGB-0 suspension in water. Based on the MTT assay, the cytotoxicity of PGB-0-F and PGB-0-Sor were higher than PGB-0 even though still categorized as low cytotoxic agents. In conclusion, we provided PGB-0 with a new method and improved its solubility in water. Further investigations are still needed to develop more efficient PGB-0 as boron carrier for BNCT in various cancers.

Pentagamaboronon-0 (PGB-0), a curcumin analog compound, has been synthesized as a candidate of boron-carrier pharmaceutical (BCP) for boron neutron capture therapy (BNCT); however, this compound is poorly soluble in water. To improve its solubility, aqueous formulations of PGB-0 with a monosaccharide, fructose or sorbitol, were successfully synthesized, namely PGB-0-F and PGB-0-So, respectively. The cytotoxicity study showed that PGB-0-F and PGB-0-So exerted low cytotoxicity against MCF-7 and MDA-MB 231 breast cancer cells. The cellular uptake study using inductively coupled plasma optical emission spectrometry (ICP-OES) and DAHMI live-cell imaging indicated that these compounds were accumulated and distributed within the cytoplasm and cell nuclei. The cellular uptake mechanism was also evaluated to clarify the contribution of the glucose transporter, and the results demonstrated that these compounds entered through active transport into MCF-7 cells but through passive diffusion into MDA-MB 231 cells. In conclusion, the sugar formulations of PGB-0 only improved PGB-0 solubility but had no role in its cellular uptake.

The chemoprevention-curcumin analog 1.1 (CCA-1.1) is a derivative of Pentagamavunone-1 (PGV-1) equipped with augmented chemical and physical properties. This study explores the potential therapeutic targets and pathways of CCA-1.1 for colon cancer treatment using bioinformatic studies. Gene mutations associated with colon cancer were retrieved from the cBioPortal public database. Target genes of CCA-1.1 were obtained from seven online databases. We then analyzed the gene ontology profiles, KEGG-related pathways, protein–protein interaction (PPI) networks, related diseases, and drug associations of the potential target genes. A total of 914 mutated genes and 812 predictive target genes of CCA-1.1 were aligned, resulting in 93 genes of matches genes mainly enriched in the pathways of cancer metabolism and EGFR tyrosine-kinase inhibitor resistance. The top 20 hub genes showed major involvement in colorectal cancer. Drug association analysis demonstrated that CCA-1.1 was mostly related to protein kinase inhibitors. Three genes, including TP53, MAPK1, and ERBB2, were revealed as noticeable target genes of CCA-1.1; these were involved in colon cancer-related pathways and had important prognostic value. Overall, the putative target genes of CCA-1.1, including TP53, MAPK1, and ERBB2, and related pathways identified in this study, suggest a possible mechanism of CCA-1.1 that could contribute to the anti-colon cancer drug development.

The detection of boron-containing compounds requires very expensive facilities and/or tedious sample pretreatments. In an effort to develop a convenient detection method for boronic acid derivatives, boron chelating-ligands were synthesized for use as fluorescent sensors. In this paper, the synthesis and properties of fluorescent sensors for boronic acid derivatives are reported.

Purpose The purpose of this study was to establish a practical method to estimate the absolute boron concentrations in the tissues based on the standardized uptake values (SUVs) after administration of 4-borono-phenylalanine (BPA) using 4-borono-2-18F-fluoro-phenylalanine (18F-FBPA) PET. Methods Rat xenograft models of C6 glioma (n = 7, body weight 241 ± 28.0 g) were used for the study. PET was performed 60 min after intravenous injection of 18F-FBPA (30.5 ± 0.7 MBq). After the PET scanning, BPA-fructose (167.3 ± 18.65 mg/kg) was administered by slow intravenous injection to the same subjects. The rats were killed 60 min after the BPA injection and tissue samples were collected from the major organs and tumors. The absolute boron concentrations (unit: ppm) in the samples were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The boron concentrations in the tissues/tumors were also estimated from the 18F-FBPA PET images using the following formula: estimated absolute boron concentration (ppm) = 0.0478 × [BPA dose (mg/kg)] × SUV. The measured absolute boron concentrations (mBC) by ICP-OES and the estimated boron concentrations (eBC) from the PET images were compared. Results The percent difference between the mBC and eBC calculated based on the SUVmax was −5.2 ± 21.1% for the blood, −9.4 ± 22.3% for the brain, 1.6 ± 21.3% for the liver, −14.3 ± 16.8% for the spleen, −9.5 ± 27.5% for the pancreas, and 3.4 ± 43.2% for the tumor. Relatively large underestimation was observed for the lung (−48.4 ± 16.2%), small intestine (−37.8 ± 19.3%) and large intestine (−33.9 ± 11.0%), due to the partial volume effect arising from the air or feces contained in these organs. In contrast, relatively large overestimation was observed for the kidney (34.3 ± 29.3%), due to the influence of the high uptake in urine. Conclusions The absolute boron concentrations in tissues/tumors can be estimated from the SUVs on 18F-FBPA PET using a practical formula. Caution must be exercised in interpreting the estimated boron concentrations in the lung, small intestine and large intestine, to prevent the adverse effects of overexposure, which could occur due to underestimation by partial volume effect using PET. Electronic supplementary material The online version of this article (doi:10.1007/s12149-017-1172-5) contains supplementary material, which is available to authorized users.

[Background]Boron neutron capture therapy (BNCT) is a unique particle radiation therapy based on the nuclear capture reactions in boron-10. We developed a novel boron-10 containing sodium borocaptate (BSH) derivative, 1-amino-3-fluorocyclobutane-1-carboxylic acid (ACBC)-BSH. ACBC is a tumor selective synthetic amino acid. The purpose of this study was to assess the biodistribution of ACBC-BSH and its therapeutic efficacy following Boron Neutron Capture Therapy (BNCT) of the F98 rat glioma. [Methods]We evaluated the biodistribution of three boron-10 compounds, ACBC-BSH, BSH and boronophenylalanine (BPA), in vitro and in vivo, following intravenous (i.v.) administration and intratumoral (i.t.) convection-enhanced delivery (CED) in F98 rat glioma bearing rats. For BNCT studies, rats were stratified into five groups: untreated controls, neutron-irradiation controls, BNCT with BPA/i.v., BNCT with ACBC-BSH/CED, and BNCT concomitantly using BPA/i.v. and ACBC-BSH/CED. [Results]In vitro, ACBC-BSH attained higher cellular uptake F98 rat glioma cells compared with BSH. In vivo biodistribution studies following i.v. administration and i.t. CED of ACBC-BSH attained significantly higher boron concentrations than that of BSH, but much lower than that of BPA. However, following convection enhanced delivery (CED), ACBC-BSH attained significantly higher tumor concentrations than BPA. The i.t. boron-10 concentrations were almost equal between the ACBC-BSH/CED group and BPA/i.v. group of rats. The tumor/brain boron-10 concentration ratio was higher with ACBC-BSH/CED than that of BPA/i.v. group. Based on these data, BNCT studies were carried out in F98 glioma bearing rats using BPA/i.v. and ACBC-BSH/CED as the delivery agents. The corresponding mean survival times were 37.4 ± 2.6d and 44.3 ± 8.0d, respectively, and although modest, these differences were statistically significant. [Conclusions]Our findings suggest that further studies are warranted to evaluate ACBC-BSH/CED as a boron delivery agent.

Boron-neutron capture therapy (BNCT) is an attractive technique for cancer treatment. As such, α, α-cycloalkyl amino acids containing thiododecaborate ([B12H11](2-)-S-) units were designed and synthesized as novel boron delivery agents for BNCT. In the present study, new thiododecaborate α, α-cycloalkyl amino acids were synthesized, and biological evaluation of the boron compounds as boron carrier for BNCT was carried out.

The highly regioselective monoarylation of 1-methyl-2-phenyl-1H-benzimidazole has been demonstrated. The reaction of 1-methyl-2-phenyl-1H-benzimidazole with 4-iodoanisole provided 2-(4′-methoxybiphenyl-2-yl)-1-methyl-1H-benzimidazole as the sole product in 96% isolated yield in the presence of [RuCl2(p-cymene)]2 and triphenylphosphine as precatalysts. A series of novel 2-(biphenyl-2-yl)benzimidazoles have been synthesized in good to excellent yields.

This paper reports our recent results from synthesis of some useful heterocycles, for example oxazolidinones, indoles, and quinoxalinones, by transition metal-catalyzed cascade processes. The scope and limitations of these procedures and the reaction mechanism for formation of the heterocycles are also discussed.

Clear cell sarcoma of tendons and aponeuroses (CCS) is a rare malignant tumor with no effective treatment. This study demonstrates the efficacy of BNCT with the use of human CCS-bearing nude mice. Groups A and C were administered saline, and groups B and D were injected with p-borono- l -phenylalanine-fructose complex. Groups C and D were then irradiated with thermal neutrons. The tumors in only group D disappeared, demonstrating that BNCT is a potentially new option for the treatment of human CCS.

Previous studies have demonstrated that angiogenesis inhibitors can enhance tumor inhibitory effects of chemo- and radiotherapy via their action on tumor vessels. Here, we studied the effect of the angiogenesis inhibitor, bevacizumab (Avastin), on boron distribution in a murine tumor model. The human head and neck squamous cell carcinoma cell line was used for inoculation into mice. Boron-10 concentrations in tissues were measured by prompt γ-ray spectrometry (PGA). Hoechst 33342 perfusion and p-boronophenylalanine (BPA) distribution were determined by immunofluorescence staining. Our results revealed enhanced tumor blood perfusion and BPA accumulation in tumors after Avastin treatment, suggesting that combination of angiogenesis inhibition with treatment with boron compound administration may improve the efficacy of boron neutron capture therapy (BNCT) by modifying tumor vessels. In addition, our results also demonstrated the usefulness of immunofluorescence staining for investigating boron compound distribution at the cellular level.

Both enantiomers of the C7-C12 segment (3 and 4) of antitumor antibiotics epothilones (1and 2) were synthesized from methyl (R)- and (S)-3-hydroxy-2-methylpropionate (5 and 6) in five steps in a fair yield.

Background Boron neutron capture therapy (BNCT) is a cellular-level particle radiation therapy that combines the selective delivery of boron compounds to tumour tissue with neutron irradiation. L-p-Boronophenylalanine (L-BPA) is a boron compound now widely used in clinical situations. Determination of the boron distribution is required for successful BNCT prior to neutron irradiation. Thus, positron emission tomography with [18F]-L-FBPA, an 18F-labelled radiopharmaceutical analogue of L-BPA, was developed. However, several differences between L-BPA and [18F]-L-FBPA have been highlighted, including the different injection doses and administration protocols. The purpose of this study was to clarify the equivalence between L-BPA and [19F]-L-FBPA as alternatives to [18F]-L-FBPA. Methods SCC-VII was subcutaneously inoculated into the legs of C3H/He mice. The same dose of L-BPA or [19F]-L-FBPA was subcutaneously injected. The time courses of the boron concentrations in blood, tumour tissue, and normal tissue were compared between the groups. Next, we administered the therapeutic dose of L-BPA or the same dose of [19F]-L-FBPA by continuous infusion and compared the effects of the administration protocol on boron accumulation in tissues. Results There were no differences between L-BPA and [19F]-L-FBPA in the transition of boron concentrations in blood, tumour tissue, and normal tissue using the same administration protocol. However, the normal tissue to blood ratio of the boron concentrations in the continuous-infusion group was lower than that in the subcutaneous injection group. Conclusions No difference was noted in the time course of the boron concentrations in tumour tissue and normal tissues between L-BPA and [19F]-L-FBPA. However, the administration protocol had effects on the normal tissue to blood ratio of the boron concentration. In estimating the BNCT dose in normal tissue by positron emission tomography (PET), we should consider the possible overestimation of the normal tissue to blood ratio of the boron concentrations derived from the values measured by PET on dose calculation. Electronic supplementary material The online version of this article (doi:10.1186/s12885-016-2913-x) contains supplementary material, which is available to authorized users.

Several amino acids were tested to catalyze the transition-metal-free direct C-H arylation of unactivated benzene derivatives. Among them, proline was found to be an excellent catalyst for the cross-coupling between aryl halides and unactivated arenes. The reaction presumably involves an aryl radical anion as the intermediate based on several experiments. The reaction using this catalyst system offers an option toward establishing an environmentally benign and cost-effective route to biaryls.

An efficient and convenient access to 1-substituted indazol-3-ones 2 has been achieved throughout the intramolecular C-N bond formations of 2-chloro-benzoic acid-N'-aryl and alkyl-hydrazides employing 0.5 mol% of cuprous (I) iodide and 20 mol% of L-proline as catalyst precursors under mild conditions in moderate to excellent yields.

A general, straightforward, and practical access to multi-substituted chiral quinoxalin-2-ones has been achieved based on the copper(I) chloride-dimethylethylenediamine (DMEDA) catalyst system. With the use of 1 mol% copper(I) chloride, structurally diverse quinoxalin-2-ones were generated with high optical purity from readily available starting materials, 2-haloanilines and α-amino acids, in a one-pot manner.

A simple synthetic route to cinnamyl-sesamols has been developed starting from sesamol via Claisen rearrangement followed by olefin metathesis reaction.

It is necessary to explore new treatments for recurrent head and neck malignancies (HNM) to avoid severe impairment of oro-facial structures and functions. Boron neutron capture therapy (BNCT) is tumor-cell targeted radiotherapy that has significant superiority over conventional radiotherapies in principle. We have treated with BNCT 42 times for 26 patients (19 squamous cell carcinomas (SCC), 4 salivary gland carcinomas and 3 sarcomas) with a recurrent and far advanced HNM since 2001. Results of (1) (10)B concentration of tumor/normal tissue ratios (T/N ratio) of FBPA-PET studies were SCC: 1.8-5.7, sarcoma: 2.5-4.0, parotid tumor: 2.5-3.7. (2) Therapeutic effects were CR: 12 cases, PR: 10 cases, PD: 3 cases NE (not evaluated): 1 case. Response rate was 85%. (3) Improvement of QOL such as a relief of severe pain, bleeding, and exudates at the local lesion, improvement of PS, disappearance of ulceration, covered with normal skin and preserved oral and maxillofacial functions and tissues. (4) Survival periods after BNCT were 1-72 months (mean: 13.6 months). Six-year survival rate was 24% by Kaplan-Meier analysis. (5) Adverse-events were transient mucositis and alopecia in most of the cases; three osteomyelitis and one brain necrosis were recognized. These results indicate that BNCT represents a new and promising treatment approach for advanced HNM.

We evaluate the clinical results of a form of tumor selective particle radiation known as boron neutron capture therapy (BNCT) for newly-diagnosed glioblastoma (NDGB) patients, especially in combination with X-ray treatment (XRT). Between 2002 and 2006, we treated 21 patients of NDGB with BNCT utilizing sodium borocaptate and boronophenylalanine simultaneously. The first 10 were treated with only BNCT (protocol 1), and the last 11 were treated with BNCT followed by XRT of 20 to 30 Gy (protocol 2) to reduce the possibility of local tumor recurrence. No chemotherapy was applied until tumor progression was observed. The patients treated with BNCT (protocol 1 plus 2) showed a significant survival prolongation compared with the institutional historical controls. BNCT also showed favorable results in correspondence with the RTOG- and EORTC-RPA subclasses. The median survival time (MST) was 15.6 months for protocols 1 and 2 together. For protocol 2, the MST was 23.5 months. The main causes of death were cerebrospinal fluid dissemination as well as local recurrence. Our modified BNCT protocol showed favorable results of patients with NDGB not only for those with good prognoses but also for those with poor prognoses.

At present p-(10B)borono- l -phenylalanine ( l -10Bpa) is used clinically as an excellent 10B carrier for BNCT; however, its enantioselective synthesis has not been reported yet. The present Letter describes the first and practical method for enantioselective synthesis of 10B-enriched l -Bpa using Z- l -Ser–OMe as the chiral synthon in good total yield and high optical purity.

A variety of 1-alkyl- and aryl-substituted indazolones were synthesized easily starting from commercially available 2-halobenzoic acids and hydrazines via the copper-catalyzed intramolecular C-N bond formation of 2-halobenzohydrazides under mild conditions.

Object Boron neutron capture therapy (BNCT) requires selective delivery of a high concentration of boron-10 (10B) to tumor tissue. To improve a drug delivery in BNCT, we devised transferrin-conjugated polyethylene-glycol liposome encapsulating sodium borocaptate (TF-PEG-BSH). Methods10B concentrations of U87Δ human glioma cells from three boron delivery systems (BDS) (bare BSH, PEG-BSH, and TF-PEG-BSH) were analyzed in vitro by use of inductively coupled plasma-atomic emission spectrometry (ICP-AES). A colony-forming assay (CFA) was performed using this cell line with the three BDS and neutron irradiation. Subcellular localization of BSH in tumor cells was analyzed in vitro by immunocytochemistry using monoclonal antibodies raised for BSH. Brain tumor models were made and the 10B concentrations of the tumor, blood, and normal brain from each BDS were analyzed in vivo by use of ICP-AES. The tumor-to-blood and the tumor-to-normal brain ratios were evaluated. BNCT for the brain tumor models was performed and survival was analyzed. Results In CFA, TF-PEG-BSH showed the most prominent effects by neutron irradiation among the three BDS. TF-PEG-BSH showed highly selective and highly efficient 10B delivery in tumor tissue. The survival rate in the treatment experiment was best in the TF-PEG-BSH group. Immunocytochemically, TF-PEG-BSH delivered BSH efficiently not only into the cytoplasm but also into the nucleus. Conclusion TF-PEG-BSH is a potent BDS for BNCT not only in terms of delivering a high concentration of 10B into tumor tissue, but also the selective delivery of 10B into the tumor cells.