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The widespread and popular use of TADs for orthodontic anchoring has become a daily routine in clinical orthodontic treatment. However, as there have been many accidents over the past decade, safety action is needed to help reduce these accidents. We have advocated using the surgical guide and developed a procedure that can benefit patients and orthodontists. The first part of this paper is about the rationale for making the surgical guide for various implant placements that were observed. Due to their anatomical structure, some placements may require particular attention, which is focused on and discussed in length. The second part deals with fabricating the surgical guide in the laboratory procedure. The data from the intraoral SLT acquisition was extracted, and with the DICOM data from CBCT and in a 3-Shapes software, the guidance was designed. The detailed and step-by-step laboratory procedure, CAD/CAM, and 3D printers to make the surgical guide for TADs are explained. The procedure is performed in an easy-to-understand manner to make using the surgical guide possible for the daily practice of orthodontics (Pubmed).

The antitumor effects of the camptothecin (CPT) derivative CPT-11, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin , were tested on human tumor xenografts in nude mice. CPT-11 showed antitumor activity higher than that of Adriamycin, 5-fluorouracil, or futraful, with little or no reduction of body weight being observed in the mice. The growth of colon adenocarcinoma Co-4 was significantly inhibited after a single i.v. injection of CPT-11 at 25, 50, or 100 mg/kg. The single i.v. injection was also significantly effective against mammary carcinoma MX-1 and gastric adenocarcinoma St-15. All of the mice bearing MX-1 tumors were cured by the administration of CPT-11 every 4 days for a total of three treatments at a total dose of 200 mg/kg given i.v. or of 400 mg/kg given p.o. Three i.v. or oral treatments were also effective against Co-4, St-15, gastric adenocarcinoma SC-6, and squamous-cell lung carcinoma QG-56. To achieve the same efficacy attained by i.v. injection, however, oral doses 2-4 times higher than the i.v. doses were required. When the total dose was fixed at 100 mg/kg, a triple i.v. injection was most effective, followed by a single i.v. injection and, finally daily p.o. administration for 10 days. Although SN-38 (7-ethyl-10-hydroxycamptothecin), a metabolite of CPT-11, showed much stronger cytotoxic activity in vitro than did CPT-11, its antitumor effects were similar, if not inferior, to those of CPT-11 in vivo at the same dose level. CPT-11 was converted into SN-38 by human tumors, but the sensitivity of these tumors to CPT-11 in vivo was independent of their ability to produce SN-38. These results suggest that CPT-11 may be clinically effective, depending on the schedule of administration, but that its effectiveness is not related to the ability of the tumor to produce SN-38. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease, and consequently, effective antifibrotic drugs are strongly desired. Although we have previously reported a validated Col1a1-Luc Tg rat model for fibrosis, there are only a few mouse models that enable the evaluation of fibrosis in a short time period and with high sensitivity. Therefore, we generated a Col1a1-internal ribosome entry site (IRES)-Luc knock-in (KI) mouse in which the IRES-luciferase gene construct was inserted into the 3'-UTR of the type I collagen alpha 1 gene (Col1a1). There was a high correlation between luciferase activity and hydroxyproline content in the KI mice, which is similar to the result that we have previously reported for the Col1a1-Luc Tg rat model. In a bleomycin (BLM)-induced lung fibrosis model, luciferase activity in the lung showed a significant increase 3 days after BLM treatment, while only a slight increase was observed in the hydroxyproline content. An ALK-5 inhibitor-R-268712-was effective in inhibiting the luciferase activity in both the in vivo BLM-induced lung fibrosis model and in vitro primary mouse lung fibroblasts. This suggests that fibroblasts are the major collagen-producing cells in lung fibrosis. In human lung fibroblasts, TGF-β stimulation induced α-smooth muscle actin as observed by immunostaining, suggesting that myofibroblast transdifferentiation (MTD) plays an important role in lung fibrosis. Together, these results indicated that ALK-5 inhibitors might affect lung fibrosis mainly via the inhibition of MTD. Thus, the Col1a1-IRES-Luc KI mouse might be useful for the evaluation of antifibrotic effects and their underlying mechanisms., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

We have published p53-MDM2 interaction inhibitors possessing a novel dihydroimidazothiazole scaffold. Although our lead compound 1 showed strong antitumor activity with single oral administration on a xenograft model using MV4-11 cells harboring wild-type p53, it needed a higher dose (200mg/kg) for distinct efficacy. We executed further optimization with the aim of improvement of potency and physicochemical properties. Thus optimal compounds were furnished by introducing fluorine moieties onto the phenyl ring at the C-6 position and the pyrrolidine part at the C-2 substituent; and modifying the terminal piperazine to 4,7-diazaspiro[2,5]octane variants. Furthermore, replacing 4-chlorophenyl on the C-5 position with pyridyl variant decreased nonspecific cytotoxicity significantly. Our exploration afforded DS-5272 indicating excellent antitumor efficacy from a dose of 25mg/kg on SJSA-1 xenografted models with high safety and good PK profiles, which has appropriate potency as a clinical candidate., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Metastasis is responsible for over 90% of cancer-associated mortality. In epithelial carcinomas, a key process in metastatic progression is the epigenetic reprogramming of an epithelial-to-mesenchymal transition-like (EMT) change towards invasive cellular phenotypes. In non-epithelial cancers, different mechanisms must underlie metastatic change, but relatively little is known about the factors involved. Here, we identify the chromatin regulatory Sirtuin factor SIRT7 as a key regulator of metastatic phenotypes in both epithelial and mesenchymal cancer cells. In epithelial prostate carcinomas, high SIRT7 levels are associated with aggressive cancer phenotypes, metastatic disease, and poor patient prognosis, and depletion of SIRT7 can reprogram these cells to a less aggressive phenotype. Interestingly, SIRT7 is also important for maintaining the invasiveness and metastatic potential of non-epithelial sarcoma cells. Moreover, SIRT7 inactivation dramatically suppresses cancer cell metastasis in vivo, independent of changes in primary tumor growth. Mechanistically, we also uncover a novel link between SIRT7 and its family member SIRT1, providing the first demonstration of direct interaction and functional interplay between two mammalian sirtuins. Together with previous work, our findings highlight the broad role of SIRT7 in maintaining the metastatic cellular phenotype in diverse cancers.

We have discovered and reported potent p53-MDM2 interaction inhibitors possessing dihydroimidazothiazole scaffold. Our lead showed strong activity in vitro, but did not exhibit antitumor efficacy in vivo for the low metabolic stability. In order to obtain orally active compounds, we executed further optimization of our lead by the improvement of physicochemical properties. Thus we furnished optimal compounds by introducing an alkyl group onto the pyrrolidine at the C-2 substituent to prevent the metabolism; and modifying the terminal substituent of the proline motif improved solubility. These optimal compounds exhibited good PK profiles and significant antitumor efficacy with oral administration on a xenograft model using MV4-11 cells having wild type p53., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

With the aim of discovering potent inhibitors of the p53-MDM2 interaction and thus obtaining a potent anticancer drug, we have pursued synthesis and optimization of dihydroimidazothiazole derivatives, which have been discovered via scaffold hopping by mimicing the mode of interaction between MDM2 and Nutlins. Upon the discovery we encountered a problem involving the chemical instability of the scaffold, that is, susceptibility to oxidation which led to imidazothiazole. In order to solve this problem and to obtain further potent compounds, we executed medicinal research and thus furnished the optimal compounds by incorporating the methyl group onto the C-6 position to avoid the oxidation, and by modifying the C-2 moiety of the additional proline motif, which furnished high potency. The incorporation of the pyrrolidine moiety at the C-2 position raised another hydrophobic interaction site with MDM2 protein, which was generated by the induced-fitting observed by co-crystal structure analysis. These optimal molecules showed significant improvement in potency when compared with the early lead (+)-1 or Nutlin-3a., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We investigated in vivo efficacies of the newly synthesized VLA-4 antagonist Compound A {trans-4-[1-[[2,5-Dichloro-4-(1-methyl-3-indolylcarboxamido)phenyl]acetyl]-(4S)methoxy-(2S)-pyrrolidinylmethoxy]cyclohexanecarboxylic acid} on Ascaris antigen-induced airway inflammation and hyperresponsiveness in a murine asthmatic model. Oral administration of Compound A significantly inhibited eosinophil infiltration into BALF and airway hyperresponsiveness 48 h after the antigen challenge. Histologic analysis of the lung sections confirmed the BALF result and revealed suppression of edema and mucus hyperplasia at 8 and 48 h after the challenge, respectively. These findings clearly show that orally active Compound A has therapeutic potential for treatment of asthma.

We have carried out the optimization of substituents at the C-3 or the C-5 position on the pyrrolidine ring of VLA-4 antagonist 3 with 2-(phenylamino)-7-fluorobenzoxazolyl moiety for the purpose of improving in vivo efficacy while maintaining good aqueous solubility. As a result, we successfully increased in vitro activity in the presence of 3% human serum albumin and achieved an exquisite lipophilic and hydrophilic balance of compounds suitable for oral administrative regimen. The modification resulted in the identification of zwitterionic compound 7n with (5S)-[methoxy(methyl)amino]methylpyrrolidine, which significantly alleviated bronchial hyper-responsiveness to acetylcholine chloride at 12.5mg/kg, p.o. in a murine asthma model and showed favorable aqueous solubility (JP1, 89 μg/mL; JP2, 462 μg/mL). Furthermore, this compound showed good oral bioavailability (F=54%) in monkeys., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Supramolecular assemblies of anilinium (Ani(+)) and fluoroanilinium derivatives (FAni(+)) with [18]crown-6 were introduced into electrically conducting [Ni(dmit)(2)] crystals (dmit(2-) is 2-thioxo-1,3-dithiole-4,5-dithiolate). The crystal structures, electrical conductivities, and magnetic susceptibilities of four new crystals of (Ani(+))([18]crown-6)[Ni(dmit)(2)](3) (1), (o-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (2), (m-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (3), and (p-FAni(+))([18]crown-6)[Ni(dmit)(2)](3) (4) were examined from the viewpoint of dynamic supramolecular rotator structures within the crystals. The crystal structures, electrical conduction, and magnetic properties were classified into group-I (crystals 1 and 4) and group-II (crystals 2 and 3). The hydrogen-bonding interaction between -NH(3)(+) and the oxygen atoms of [18]crown-6 formed the stand-up configuration of rotator-stator structures of (Ani(+))([18]crown-6) and (FAni(+))([18]crown-6) supramolecules. The potential energy barriers for the 2-fold flip-flop motion of phenyl- and p-fluorophenyl-rings in crystals 1 and 4 had a relatively small magnitude of ∼150 kJ mol(-1), suggesting that rotations of Ani(+) and p-FAni(+) cations around the C-NH(3)(+) axis occurred in the crystals. In contrast, a large magnitude of the potential energy barriers for the rotations of o-FAni(+) and m-FAni(+) cations in crystals 2 and 3 (>600 kJ mol(-1)) resulted in static supramolecular cationic structures. The cation:anion ratio of 1:3 in these crystals yielded a trimer π-stack of [Ni(dmit)(2)] with a semiconductor-like temperature dependence. The magnetic susceptibilities of the static crystals 2 and 3 were reproduced by the one-dimensional antiferromagnetic linear Heisenberg chain through the one-dimensional linear trimer arrangement. The magnetic susceptibilities of dynamic crystals 1 and 4 enhanced electron delocalization through the intratrimer and intertrimer interactions within the trimer stack, where the molecular rotations of Ani(+) and p-FAni(+) cations played an important role.

Starting with Nutlins as an initial lead, we designed and generated bicyclic scaffolds aiming to place cis-bischlorophenyl moiety at the equivalent location where the hydrophobic interaction with MDM2 could be expected. As a result, we discovered novel MDM2 inhibitors possessing a dihydroimidazothiazole scaffold. Further exploration of the side chains on the dihydroimidazothiazole scaffold aided by molecular modeling resulted in compounds exhibiting almost comparable in vitro potency to Nutlin-3a., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

For the purpose of obtaining orally potent VLA-4 inhibitors, we have carried out structural modification of the (N'-phenylureido)phenyl group in compound 1, where the group was found to be attributed to poor pharmacokinetic profile in our previous research. Through modification, we have identified several compounds with both potent in vitro activity and improved oral exposure. In particular, compound 7e with 7-fluoro-2-(1-methyl-1H-indol-3-yl)-1,3-benzoxazolyl group as a novel replacement of the (N'-phenylureido)phenyl group significantly inhibited eosinophil infiltration into bronchoalveolar lavage fluid at 15mg/kg in an Ascaris-antigen-induced murine bronchial inflammatory model, and its efficacy was comparable to that of the anti-mouse α(4) antibody (R1-2)., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Neurons, astrocytes, and oligodendrocytes-the three major cell types that comprise the central nervous system-are generated from common multipotent neural precursor cells (NPCs). Members of the interleukin-6 family of cytokines, including leukemia inhibitory factor (LIF), induce astrocyte differentiation of NPCs by activating the transcription factor signal transducer and activator of transcription 3 (STAT3). We show here that retinoic acid (RA) facilitates LIF-induced astrocyte differentiation of NPCs. RA and LIF synergistically activate the promoter of gfap, which encodes the astrocytic marker glial fibrillary acidic protein, and a putative RA response element in the promoter was found to be critical for this activation. Histone H3 acetylation around the STAT-binding site in the gfap promoter was increased in NPCs treated with RA, allowing STAT3 to gain access to the promoter more efficiently. These results suggest that RA acts in concert with LIF to induce astrocyte differentiation of NPCs through an epigenetic mechanism that involves cross-talk between distinct signaling pathways.

Sandwich-type (Cs(+))(2)(benzo[18]crown-6)(3) and (Cs(+))(dibenzo[18]crown-6)(2) supramolecular cations were introduced as counterions of [Ni(dmit)(2)](-) (dmit(2-) = 2-thione-1,3-dithiole-4,5-dithiolate) anions to induce unique [Ni(dmit)(2)](-) anion (S = 1/2) arrangements and magnetic properties. The magnetic exchange energy (J) between the [Ni(dmit)(2)](-) anions was dependent on the mode of the intermolecular interactions. In the case of (Cs(+))(2)(benzo[18]crown-6)(3)[Ni(dmit)(2)](-)(2) (1), the asymmetric arrangement of the [Ni(dmit)(2)](-) anions involved the coexistence of a pi-dimer chain along with a two-dimensional layer via lateral S...S contacts, in which the magnetic properties of the pi-dimer chain and the two-dimensional layer were characterized by antiferromagnetic (J = -5.2 K) and ferromagnetic coupling (Weiss temperature = +1.1 K), respectively. The unique [Ni(dmit)(2)](-) arrangements and magnetic behaviors for crystal 1 can be attributed to the asymmetrical benzo[18]crown-6. In the case of Cs(+)(dibenzo[18]crown-6)(2)[Ni(dmit)(2)](-) (2), however, the formation of the lateral [Ni(dmit)(2)](-) dimer via S...S contacts yielded antiferromagnetic coupling corresponding to the dimer model (J = -25.5 K).

Supramolecular rotators of hydrogen-bonding assemblies between anilinium (Ph-NH 3 (+)) or adamantylammonium (AD-NH 3 (+)) and dibenzo[18]crown-6 (DB[18]crown-6) or meso-dicyclohexano[18]crown-6 (DCH[18]crown-6) were introduced into [Ni(dmit) 2] salts (dmit (2-) is 2-thioxo-1,3-dithiole-4,5-dithiolate). The ammonium moieties of Ph-NH 3 (+) and AD-NH 3 (+) cations were interacted through N-H (+) approximately O hydrogen bonding with the six oxygen atoms of crown ethers, forming 1:1 supramolecular rotator-stator structures. X-ray crystal-structure analyses revealed a jackknife-shaped conformation of DB[18]crown-6, in which two benzene rings were twisted along the same direction, in (Ph-NH 3 (+))(DB[18]crown-6)[Ni(dmit) 2] (-) ( 1) and (AD-NH 3 (+))(DB[18]crown-6)[Ni(dmit) 2] (-) ( 3), whereas the conformational flexibility of two dicyclohexyl rings was observed in (Ph-NH 3 (+))(DCH[18]crown-6)[Ni(dmit) 2] (-) ( 2) and (AD-NH 3 (+))(DCH[18]crown-6)[Ni(dmit) 2] (-) ( 4). Sufficient space for the molecular rotation of the adamantyl group was achieved in the crystals of salts 3 and 4, whereas the rotation of the phenyl group in salts 1 and 2 was rather restricted by the nearest neighboring molecules. The rotation of the adamantyl group in salts 3 and 4 was evidenced from the temperature-dependent wide-line (1)H NMR spectra, dielectric properties, and X-ray crystal structure analysis. ab initio calculations showed that the potential energy barriers for the rotations of adamantyl groups in salts 3 (Delta E approximately 18 kJmol (-1)) and 4 (Delta E approximately 15 kJmol (-1)) were similar to those of ethane ( approximately 12 kJmol (-1)) and butane (17-25 kJmol (-1)) around the C-C single bond, which were 1 order of magnitude smaller than those of phenyl groups in salts 1 (Delta E approximately 180 kJmol (-1)) and 2 (Delta E approximately 340 kJmol (-1)). 1D or 2D [Ni(dmit) 2] (-) anion arrangements were observed in the crystals according to the shape of crown ether derivatives. The 2D weak intermolecular interactions between [Ni(dmit) 2] (-) anions in salts 1 and 3 led to Curie-Weiss behavior with weak antiferromagnetic interaction, whereas 1D interactions through lateral sulfur-sulfur atomic contacts between [Ni(dmit) 2] (-) anions were observed in salts 2 and 4, whose magnetic behaviors were dictated by ferromagnetic (salt 2) and singlet-triplet (salt 4) intermolecular magnetic interactions, respectively.

Calcium ion (Ca2+) is one of the key regulatory elements for ciliary movements in the Paramecium species. It has long been known that members of Paramecium species including green paramecia (Paramecium bursaria) exhibit galvanotaxis which is the directed movement of cells toward the anode by swimming induced in response to an applied voltage. However, our knowledge on the mode of Ca2+ action during green paramecia anodic galvanotactic response is still largely limited. In the present study, quantification of anodic galvanotaxis was carried out in the presence and absence of various inhibitors of calcium signaling and calcium channels. Interestingly, galvanotactic movement of the cells was completely inhibited by a variety of Ca2+-related inhibitors. Such inhibitors include a Ca2+ chelator (EGTA), general calcium channel blockers (such as lanthanides), inhibitors of intracellular Ca2+ release (such as ruthenium red and neomycin), and inhibitors of T-type calcium channels (such as NNC 55-0396, 1-octanol and Ni2+). However, L-type calcium channel inhibitors such as nimodipine, nifedipine, verapamil, diltiazem and Cd2+ showed no inhibitory action. This may be the first implication for the involvement of T-type calcium channels in protozoan cellular movements.

Previously we have identified the Drosophila orbit gene whose hypomorphic mutations cause abnormal chromosome segregation (Inoue et al., 2000). The orbit encodes Orbit/Mast, a 165-kDa microtubule-associated protein (MAP) with GTP-binding motifs. Two human homologues of the Orbit/Mast, CLASP1 (hOrbit1) and CLASP2 (hOrbit2) have been identified. Using an antibody to CLASP1/hOrbit1 polypeptide, we confirmed that the polypeptide of about 150 kDa associates with microtubule purified from the porcine brain. Thus, we conjectured that CLASP1 may be a human orthologue of the Drosophila Orbit/Mast, and therefore we named it h (human) Orbit1. We constructed the plasmid for expression of a fusion protein of the putative microtubule-binding domain (1-662 out of 1289 residues) of hOrbit1 and the green fluorescent protein (GFP), and then, transfected the plasmid into Tet off cells derived from HeLa cell. Confocal laser scanning microscopic observation revealed that the GFP-fluorescence associated with short and thin filaments in the perinuclear region during the short period after plasmid transfection, and colocalized with only part of the microtubules. GFP fluorescence was later detected on the abnormally longer and thick bundles of microtubule filaments. Finally the bundles formed networks in the perinuclear region. The results suggest that the GFP-hOrbit1 N-terminal fragment (GFP-hOrbit1 NF) binds to the newly formed microtubules rather than the pre-formed ones, and that displacement of the endogenous hOrbit by the fragment might cause abnormal bundling of microtubules. Interestingly, the expression of the GFP-hOrbit1 NF results in cell death associated with nuclear fragmentation.

Irradiation of the salivary glands results in the generation of free radicals from metal ions present in the secretory granules of acinar cells, a process that is believed to exacerbate radiation damage to the salivary glands. We therefore conducted a comparative investigation of radiation damage to the acinar cells of murine submaxillary glands in which granule secretion had been induced, and used autoradiography to visualize the pathological changes. Male BALB/c mice, at 8 weeks of age, were divided into four groups: a no-isoproterenol (IPR) and no-irradiation group (group I), a no-IPR, irradiated group (group II), an IPR, no-irradiation group (group III), and an IPR, irradiated group (group IV). Intraperitoneal injections of IPR were used, and 3 h later, the submaxillary region was irradiated with X-rays at a dose of 10 Gy. Three days after the irradiation, 3H-leucine was administered, and submaxillary glands were removed at predetermined times. Thin sections were prepared, and light- and electron-microscope autoradiography was performed. The number of reduced silver particles per unit acinar cell area was determined by light-microscopic autoradiography, and the proportion of reduced silver particles in the rough endoplasmic reticulum, the Golgi apparatus, and secretion granules was determined by electron-microscopic autoradiography. The result indicated that the effects of the radiation on the secretory potential of the submaxillary glands were diminished in acinar cells with a higher secretory granule content., (Copyright 2004 The Society of the Nippon Dental University)

To elucidate the role of vascular endothelial growth factor (VEGF), an endothelial cell-specific mitogen, in tumour angiogenesis and malignant progression, an expression vector harboring human VEGF cDNA was stably transfected into three human cancer cell lines with poor VEGF productivity. Though their in vitro growth rate and intrinsic productivity of another angiogenic factor, basic fibroblast growth factor (bFGF), were not changed by transfection, those clones with higher VEGF production were endowed with tumorigenic and angiogenic potentials as follows: firstly, nontumorigenic, lung carcinoma QG90 cells having lower bFGF productivity acquired tumorigenicity as well as significant in vivo angiogenesis-inducing ability, secondly, tumorigenic colorectal carcinoma RPMI4788 cells having higher potency for bFGF production could form more vascularized solid tumour with faster growth rate and thirdly, oestrogen-dependent breast carcinoma MCF-7 cells, which did not produce detectable bFGF, acquired tumorigenicity even in the absence of oestrogen and the solid tumour growth rate was remarkably enhanced, accompanied with increased vascularization, in the presence of oestrogen. These results suggest that tumour progression closely depends on angiogenesis, and VEGF significantly contributes to malignant progression of a variety of tumour cells through its potent angiogenic activity, independent on the bFGF productivity of tumour cells.

Basic fibroblast growth factor (bFGF) plays an important role in tumor growth and angiogenesis. To elucidate the efficient recognition sites by anti-bFGF neutralizing antibodies, we generated two anti-bFGF neutralizing monoclonal IgG1 antibodies (mAbs), 2G11 and 1E6, recognizing different sites, and estimated as binding to the heparin-binding and the receptor-binding regions of bFGF, respectively, both of which have been shown to be important for its receptor interaction. Despite their high in vitro anti-bFGF activity in the absence of heparin, 2G11, with in vitro activity in competition with heparin, failed to inhibit the in vivo tumor growth of bFGF-producing RPMI4788 cells, though 1E6, showing non-competition with heparin, exhibited a significant antitumor effect. These results show that the heparin-binding domain of bFGF provides an inefficient epitope for in vivo neutralization of anti-bFGF mAb, and anti-bFGF neutralizing mAbs without competition against heparin have the potential to show in vivo antitumor effects.

The aim of this study was to determine the role of tumor-derived angiogenic factors in solid tumor formation. We compared the angiogenic potential of tumorigenic and non-tumorigenic human tumor cell lines. All tumorigenic cell lines induced angiogenesis in vivo and their angiogenesis-inducing abilities were higher than those of the other non-tumorigenic cell lines. This in vivo angiogenic potential was well correlated with the in vitro endothelial cell growth-stimulating activity contained in the cell extract or conditioned medium of each cell line. The endothelial cell growth-stimulating activities of these cell lines were completely inhibited by neutralizing antibodies to basic fibroblast growth factor (bFGF), acidic FGF (aFGF) or vascular endothelial growth factor (VEGF). Furthermore, the levels of tumor-derived endothelial cell growth-stimulating activities depended on the amounts of angiogenic factors such as VEGF and bFGF produced by tumor cells. Although VEGF transcripts were detected in all of the cell lines by RT-PCR assay, the non-tumorigenic cell lines showed poor productivity of VEGF as well as FGFs and had less or non-potency for endothelial cell growth stimulation. These findings suggest that the increase in production of angiogenic factors by tumor cells is necessary for their in vivo angiogenic and tumorigenic potentials, and that VEGF and FGFs are the major mediators of tumor-induced angiogenesis.

The hst-1 gene product, one of the fibroblast growth factor family proteins, has transforming and angiogenic activities. The BALB/c 3T3 cell line was transfected with an expression vector harboring human hst-1 cDNA and the malignant properties of two stably transfected clones, TC-1 and TC-2, were examined. The stimulating activity of TC-1-conditioned medium for endothelial cell DNA synthesis was approximately four times stronger than that of TC-2-conditioned medium and correlated with hst-1 mRNA expression levels. Other than endothelial cell growth stimulation, these two clones had similar typical in vitro transformed properties, with identical doubling times and morphological changes. When nude mice were injected s.c. with these clones, TC-1 cells revealed faster tumor formation and growth, compared to TC-2 cells which had less potential to promote endothelial cell growth. Furthermore, the life span of mice injected i.v. with TC-1 cells was shorter than those with TC-2 cells, resulting from progressive tumor growth in the lungs. This advanced malignant in vivo behavior of TC-1 cells may be mediated by the high angiogenic potential of TC-1 cells secreting larger amounts of HST-1 compared to TC-2 cells, suggesting that angiogenesis contributes to malignant progression of tumors.

Placenta Growth Factor (PIGF) is a new member of vascular endothelial growth factor (VEGF) family. Although VEGF binds Flt family Flt-1 and KDR/Flk-1 tyrosine kinases at high affinity for signal transduction, biological activities and the receptors of PIGF have not been extensively studied. Reverse transcription-PCR showed that PIGF-2, a subtype of PIGF-1 that bears a basic amino acid-rich domain, is more abundant than PIGF-1 and thus is the major subtype in human placenta. Using antibodies specific to PIGF-1 or -2 as markers, we obtained large amounts of PIGFs in the baculovirus expression system. PIGF-2 had growth-stimulatory activity on human umbilical vein endothelial cells and vascular permeability activity in the Miles assay at levels about 10-fold lower than those of VEGF. All PIGF-1 activities were lower than those of PIGF-2. Both PIGFs competed for the binding of 125I-labeled VEGF to Flt-1 receptor but not to KDR/Flk-1 expressed on NIH3T3 cells. Furthermore, 125I-labeled PIGF bound to Flt-1 at high affinity but not to KDR/Flk-1. Supporting the notion that PIGF can use only Flt-1 as a receptor, PIGF activated Flt-1 to autophosphorylate, whereas PIGF could not generate signals from KDR/Flk-1. These results indicate that Flt-1, but not KDR/Flk-1, is a receptor for PIGF, suggesting that the weak biological activities of PIGF are due to its use of only part of the available VEGF signaling. These mild characteristics of PIGF may be important for the appropriate development and maintenance of normal placental tissue.

We investigated the biodistribution and antitumour activity of doxorubicin (ADM) encapsulated in liposomes (L-ADM) after two administrations in tumour bearing mice. The effect of the first administration on phagocytic activity was also examined. The biodistribution of L-ADM after the second dosing at an interval of 4d was remarkably different from that after the first. The concentration of ADM in plasma and tumour after the second injection was higher, but that in the liver was lower than after the first administration. This decrease in distribution to the liver is thought to have contributed to the difference in the biodistribution characteristics of L-ADM. With regard to antitumour effect, the activity was similar between L-ADM and a solution of ADM (F-ADM). To investigate the effect of the first administration of L-ADM on biodistribution, systemic phagocytic activity was measured after the injection of F-ADM, L-ADM, or 'empty' liposomes not containing ADM. F-ADM and L-ADM (7.5 mg ADM/kg body weight) reduced phagocytic activity to approximately 50% and 30% of control, respectively. This finding suggests that entrapment of ADM in liposomes enhances both the distribution of the drug to the reticuloendothelial system (RES) and its suppressive effect on RES activity. These results indicate that the decrease in RES activity by L-ADM must be considered in estimation of the pharmacokinetics, antitumour activity, and toxicity of L-ADM in clinical use when given by repeat administration or used in combination with other antitumour agents.

CPT-11, a semisynthetic derivative of camptothecin, exhibited strong antitumor activity against lymphoma, lung cancer, colorectal cancer, gastric cancer, ovarian cancer, and cervical cancer. CPT-11 is a pro-drug that is converted to an active metabolite, SN-38, in vivo by enzymes such as carboxylesterase. We synthesized a water-soluble and non-pro-drug analog of camptothecin, DX-8951f. It showed both high in vitro potency against a series of 32 malignant cell lines and significant topoisomerase I inhibition. The anti-proliferative activity of DX-8951f, as indicated by the mean GI50 value, was about 6 and 28 times greater than that of SN-38 or SK&F 10486-A (Topotecan), respectively. These three derivatives of camptothecin showed similar patterns of differential response among 32 cell lines, that is, their spectra of in vitro cytotoxicity were almost the same. The antitumor activity of three doses of DX-8951f administered i.v. at 4-day intervals against human gastric adenocarcinoma SC-6 xenografts was greater than that of CPT-11 or SK&F 10486-A. Moreover, it overcame P-glycoprotein-mediated multi-drug resistance. These data suggest that DX-8951f has a high antitumor activity and is a potential therapeutic agent.

It is known that 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), a semisynthesized derivative of camptothecin (CPT), has a potent antitumor activity in vivo, but 7-ethyl-10-hydroxycamptothecin (SN-38), a metabolite of CPT-11, shows much stronger cytotoxicity in vitro than CPT-11. In this study, we demonstrated that the relaxation of SV40 DNA plasmids by type I DNA topoisomerase prepared from P388 murine leukemia cells was inhibited by 50% by SN-38 at approximately 1 microM, although CPT-11 at 1 mM slightly inhibited the relaxation. SN-38 and CPT showed strong, time-dependent inhibitory activity against DNA synthesis of P388 cells. However, CPT-11 weakly inhibited DNA synthesis independently of time with coincident inhibition of the total thymidine uptake by the cells. By alkaline and neutral elution assays, it was demonstrated that SN-38 caused much more frequent DNA single-strand breaks in P388 cells than did CPT-11. The same content of SN-38 and a similar frequency of single-strand breaks were detected in the cells treated with SN-38 at 0.1 microM or with CPT-11 at 100 microM. Therefore, single-strand breaks by CPT-11 seem to be due to SN-38 produced from CPT-11 in cells. These results indicate that CPT-11 itself possesses a marginal antiproliferative effect but that SN-38 plays an essential role in the mechanism of action of CPT-11.

Efficacy of three ultrasonographic and six biochemical methods for the detection of intrauterine growth retardation were assessed in prospective studies of 40 cases associated with short uterine fundal height less than -1.5 SD and/or small ultrasonographically determined total intrauterine volume (TIUV) less than -1 SD of normal populations. Prenatal treatments, consisting of bed rest, high protein diet, intravenous drip infusion of 10% maltose, 500 ml per day, for more than 12 days, etc., were administered on them. Fifteen cases (37.5%) delivered small-for-date infants, 9 of which complicated by toxemia of pregnancy. At the final determinations, small TIUV were found in all small-for-date cases (100%), short biparietal diameter 80.0%, and short longitudinal intracavital uterine length 53.3% of 15 small-for-date cases. In biochemical parameters, low maternal plasma estriol levels were found in 73.3%, low plasma human placental lactogen levels 66.7%, low urinary estriol excretion 53.3%, abnormal plasma alpha-fetoprotein levels 33.3%, and low plasma progesterone levels 20.0% of 15 small-for-date cases. Nineteen cases (47.5%) demonstrated remarkable increases in TIUV following prenatal treatments, and delivered appropriate-for-date infants. Despite of marked growth in biophysical parameters, abnormal biochemical values were mostly not improved by these treatments.