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Yasuhiro Matsumura

Bio: Yasuhiro Matsumura is an academic researcher from University of Tokyo. The author has contributed to research in topics: Cancer & Stromal cell. The author has an hindex of 54, co-authored 238 publications receiving 23769 citations. Previous affiliations of Yasuhiro Matsumura include Kumamoto University & John Radcliffe Hospital.


Papers
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Journal Article
TL;DR: It is speculated that the tumoritropic accumulation of smancs and other proteins resulted because of the hypervasculature, an enhanced permeability to even macromolecules, and little recovery through either blood vessels or lymphatic vessels in tumors of tumor-bearing mice.
Abstract: We previously found that a polymer conjugated to the anticancer protein neocarzinostatin, named smancs, accumulated more in tumor tissues than did neocarzinostatin. To determine the general mechanism of this tumoritropic accumulation of smancs and other proteins, we used radioactive (51Cr-labeled) proteins of various molecular sizes (Mr 12,000 to 160,000) and other properties. In addition, we used dye-complexed serum albumin to visualize the accumulation in tumors of tumor-bearing mice. Many proteins progressively accumulated in the tumor tissues of these mice, and a ratio of the protein concentration in the tumor to that in the blood of 5 was obtained within 19 to 72 h. A large protein like immunoglobulin G required a longer time to reach this value of 5. The protein concentration ratio in the tumor to that in the blood of neither 1 nor 5 was achieved with neocarzinostatin, a representative of a small protein (Mr 12,000) in all time. We speculate that the tumoritropic accumulation of these proteins resulted because of the hypervasculature, an enhanced permeability to even macromolecules, and little recovery through either blood vessels or lymphatic vessels. This accumulation of macromolecules in the tumor was also found after i.v. injection of an albumin-dye complex (Mr 69,000), as well as after injection into normal and tumor tissues. The complex was retained only by tumor tissue for prolonged periods. There was little lymphatic recovery of macromolecules from tumor tissue. The present finding is of potential value in macromolecular tumor therapeutics and diagnosis.

6,483 citations

Journal ArticleDOI
TL;DR: The basic characteristics of the EPR effect, particularly the factors involved, are described, as well as its modulation for improving delivery of macromolecular drugs to the tumor.

5,955 citations

Journal Article
TL;DR: CDDP/m could be a promising formulation of CDDP for the targeted therapy of solid tumors, according to the passive targeting manner, and its utility as a tumor-targeted drug delivery system was investigated.
Abstract: Polymeric micelles incorporating cisplatin (CDDP) were prepared through the polymer-metal complex formation between CDDP and poly(ethylene glycol)-poly(glutamic acid) block copolymers, and their utility as a tumor-targeted drug delivery system was investigated. CDDP-incorporated micelles (CDDP/m) had a size of 28 nm with remarkably narrow distribution. CDDP/m were very stable in distilled water even in long-time storage, but exhibited a sustained drug release accompanied with the decay of the carrier itself in physiological saline. These micelles showed remarkably prolonged blood circulation and effectively accumulated in solid tumors (Lewis lung carcinoma cells) according to the passive targeting manner (20-fold higher than free CDDP). Reduced accumulation of the micelles in normal organs provided high selectivity to the tumor. In vivo antitumor activity assay demonstrated that both free CDDP and the CDDP/m had significant antitumor activity in C 26-bearing mice compared with nontreatment (P < 0.05 for free CDDP; P < 0.01 for CDDP/m), but complete tumor regression was observed only for the treatment with CDDP/m. Four of 10 mice treated with CDDP/m (4 mg/kg; five times administration at 2-day intervals) showed complete tumor regression with no significant body weight loss, whereas free CDDP treatment at the same drug dose and regime resulted in tumor survivals and approximately 20% of body weight loss. These data suggest that CDDP/m could be a promising formulation of CDDP for the targeted therapy of solid tumors.

593 citations

Journal Article
TL;DR: Improvements in protein drugs, after tailoring with polymers, are as follows: increased plasma half-life, loss of antigenecity, lymphotropism, and, especially, preferred tumor-targeting efficiency and long-term retention in the tumor tissues.
Abstract: The advantages and disadvantages of macromolecular drugs, particularly on synthetic polymer-protein conjugates, are described in this article. Improvements in protein drugs, after tailoring with polymers, are as follows: increased plasma half-life, loss of antigenecity, lymphotropism, and, especially, preferred tumor-targeting efficiency and long-term retention in the tumor tissues. Hydrophobic character can make a drug also possible for oily formulation. Explained are the rationales of macromolecular drugs to preferential delivery to the tumor and lymphatic tissues based on our finding on pathological/anatomical differences of the blood and lymphatic vasculatures. Enhanced vascular permeability, which facilitates the macromolecular drug-leakage out of the blood vessel, is discussed. A model compound, which is discussed in detail, is smancs--styrene-co-maleic acid conjugated neocarzinostatin (MW 16 K). Some data on polymer-conjugated enzymes as potential therapeutic agents are described as well.

581 citations

Journal ArticleDOI
TL;DR: The maximum-tolerated dose (MTD) and dose-limiting toxicities (DLTs) of NK911 were defined and a partial response was obtained in one patient with metastatic pancreatic cancer and its pharmacokinetic profile in man was well tolerated.
Abstract: NK911 is a novel supramolecular nanocarrier designed for the enhanced delivery of doxorubicin (DXR) and is one of the successful polymer micelle systems to exhibit an efficient accumulation in solid tumours in mice. The purpose of this study was to define the maximum-tolerated dose (MTD) and dose-limiting toxicities (DLTs) of NK911 and to evaluate its pharmacokinetic profile in man. NK911 was given intravenously to patients with solid tumours every 3 weeks using an infusion pump at a rate of 10 mg DXR equivalent min(-1). The starting dose was 6 mg DXR equivalent m(-2), and the dose was escalated according to the accelerated titration method. A total of 23 patients participated in this study. Neutropenia was the predominant haematological toxicity, and grade 3 or 4 neutropenia was observed at doses of 50 and 67 mg m(-2). Common nonhaematological toxicities were mild alopecia, stomatitis, and anorexia. In the dose identification part of the study, DLTs were observed at a dose of 67 mg m(-2) (grade 4 neutropenia lasting more than 5 days). Thus, this dosage level was determined to be the MTD. Infusion-related reactions were not observed in any cases. The C(5 min) and area under the concentration curve parameters of NK911 exhibited dose-dependent characteristics. Among the 23 patients, a partial response was obtained in one patient with metastatic pancreatic cancer. NK911 was well tolerated and produced only moderate nausea and vomiting at myelosuppressive dosages. The recommended phase II dose was determined to be 50 mg m(-2) every 3 weeks.

579 citations


Cited by
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Journal ArticleDOI
TL;DR: The arsenal of nanocarriers and molecules available for selective tumour targeting, and the challenges in cancer treatment are detailed and emphasized.
Abstract: Nanotechnology has the potential to revolutionize cancer diagnosis and therapy. Advances in protein engineering and materials science have contributed to novel nanoscale targeting approaches that may bring new hope to cancer patients. Several therapeutic nanocarriers have been approved for clinical use. However, to date, there are only a few clinically approved nanocarriers that incorporate molecules to selectively bind and target cancer cells. This review examines some of the approved formulations and discusses the challenges in translating basic research to the clinic. We detail the arsenal of nanocarriers and molecules available for selective tumour targeting, and emphasize the challenges in cancer treatment.

7,443 citations

Journal ArticleDOI
TL;DR: The basic characteristics of the EPR effect, particularly the factors involved, are described, as well as its modulation for improving delivery of macromolecular drugs to the tumor.

5,955 citations

Journal ArticleDOI
TL;DR: By successively addressing each of the biological barriers that a particle encounters upon intravenous administration, innovative design features can be rationally incorporated that will create a new generation of nanotherapeutics, realizing a paradigmatic shift in nanoparticle-based drug delivery.
Abstract: Biological barriers to drug transport prevent successful accumulation of nanotherapeutics specifically at diseased sites, limiting efficacious responses in disease processes ranging from cancer to inflammation. Although substantial research efforts have aimed to incorporate multiple functionalities and moieties within the overall nanoparticle design, many of these strategies fail to adequately address these barriers. Obstacles, such as nonspecific distribution and inadequate accumulation of therapeutics, remain formidable challenges to drug developers. A reimagining of conventional nanoparticles is needed to successfully negotiate these impediments to drug delivery. Site-specific delivery of therapeutics will remain a distant reality unless nanocarrier design takes into account the majority, if not all, of the biological barriers that a particle encounters upon intravenous administration. By successively addressing each of these barriers, innovative design features can be rationally incorporated that will create a new generation of nanotherapeutics, realizing a paradigmatic shift in nanoparticle-based drug delivery.

4,457 citations

Journal ArticleDOI
TL;DR: Nanotechnology is a multidisciplinary field, which covers a vast and diverse array of devices derived from engineering, biology, physics and chemistry that can provide essential breakthroughs in the fight against cancer.
Abstract: Nanotechnology is a multidisciplinary field, which covers a vast and diverse array of devices derived from engineering, biology, physics and chemistry. These devices include nanovectors for the targeted delivery of anticancer drugs and imaging contrast agents. Nanowires and nanocantilever arrays are among the leading approaches under development for the early detection of precancerous and malignant lesions from biological fluids. These and other nanodevices can provide essential breakthroughs in the fight against cancer.

4,241 citations

Journal ArticleDOI
19 Mar 2004-Science
TL;DR: There is considerable interest in exploiting the advantages of DDS for in vivo delivery of new drugs derived from proteomics or genomics research and for their use in ligand-targeted therapeutics.
Abstract: Drug delivery systems (DDS) such as lipid- or polymer-based nanoparticles can be designed to improve the pharmacological and therapeutic properties of drugs administered parenterally. Many of the early problems that hindered the clinical applications of particulate DDS have been overcome, with several DDS formulations of anticancer and antifungal drugs now approved for clinical use. Furthermore, there is considerable interest in exploiting the advantages of DDS for in vivo delivery of new drugs derived from proteomics or genomics research and for their use in ligand-targeted therapeutics.

4,162 citations