Chugai Seiyaku Kabushiki Kaisha

Pharmalogicals Research Pte. Ltd.

Ciea International Inc.

Koichi Matsubara

Masami Suzuki

Atsuhiko Kato

Shinta Kobayashi

Yu Jau Chen

Tatsumi Yamazaki

Hisafumi Okabe

Takeshi Watanabe

Masayuki Tsuchiya

Miho Watanabe

Kenji Yoshida

Etsuko Fujii

Juliana Sim

Osamu Natori

Chie Kato

Masaki Yamazaki

Provided is a cancer stem cell mass from which cells incapable of forming cancer are substantially removed and which has a characteristic property of reproducing a layered structure of a cancer tissue; a process for producing the cancer stem cell mass; and use of the cancer stem cell mass. A human cancer tissue was repeatedly grown in a NOG mouse, separated cancer cells from the grown cancer tissue, and tested and compared various cancer cell culture processes. As a result, a cancer stem cell composition which is homogeneous and is substantially free of the coexistence of cells capable of forming cancer and cells incapable of forming cancer in a mixed state can be produced successively by employing an attached culture process using a serum-free stem cell culture medium rather than a generally employed floating culture process.

Cancer stem cell population and method for production thereof

An objective of the present invention is to obtain two types of substantively homogeneous cancer stem cell populations which can be characterized using the cell surface marker Lgr5, and to provide cancer therapeutics using an antibody against a cell membrane molecule specifically expressed in these cancer stem cells by identifying said cell membrane molecule. A further objective is to provide, using an antibody against a cell membrane molecule specifically expressed in cancer stem cells, a reagent for detecting cancer stem cells, and a method for diagnosing and sorting cancer patients. The present inventors discovered that highly pure large intestine cancer stem cells (CSC) can be obtained in a large quantity, and identified the two types of conditions of large intestine CSCs distinguishable through Lgr5 expression. Moreover, the present inventors discovered that an antibody against a cell membrane molecule specifically expressed in said cancer stem cells can damage said cells.

Cancer stem cell-specific molecule

An objective of the present invention is to provide non-human animal models of cancer pathology, which mimic the hierarchical organization, cancer progression process, or biological property of human cancer tissues, and uses thereof. To achieve the objective described above, first, the present inventors transplanted cells of NOG-established cancer lines into NOG mice and morphologically observed the resulting tissue organization. As a result, the non-human animal models were demonstrated to exhibit pathologies (the hierarchical organization, cancer progression process, or biological properties of the cancer cells) similar to that of human cancer. Specifically, the present inventors succeeded in preparing non-human animal models exhibiting pathologies more similar to a human cancer, and cell culture systems using NOG-established cancer cell lines where the in vitro cell morphology is more similar to that of human cancer.

Method for searching and screening for target of anti-cancer agent using non-human animal model having NOG established cancer cell line transplanted therein

The purpose of the present invention is to provide: a cancer stem cell mass from which cells incapable of forming cancer are substantially removed and which has a characteristic property of reproducing a layered structure of a cancer tissue; a process for producing the cancer stem cell mass; and use of the cancer stem cell mass. For achieving the purpose, the present inventors grew a human cancer tissue repeatedly in a NOG mouse, separated cancer cells from the grown cancer tissue, and made a comparison of various cancer cell culture processes with each other. As a result, a cancer stem cell composition which is homogeneous and is substantially free of the coexistence of cells capable of forming cancer and cells incapable of forming cancer in a mixed state can be produced successively by employing an attached culture process using a serum-free stem cell culture medium rather than a generally employed floating culture process, and consequently the present invention has been accomplished.

An objective of the present invention is to provide: a cancer stem cell isolated using a cell marker; a substantively homogeneous cancer stem cell population including said cancer stem cell; and a method of preparing said cancer stem cell population. Another objective of the present invention is to provide: a method for separating cancer stem cells with a high proliferative potential and those with a low proliferative potential; a method for inducing cancer stem cells to have a different proliferative potential; and cancer stem cells separated or induced by these separation or induction methods. A further objective of the present invention is to provide: a method of screening for pharmaceuticals using said cancer stem cell or cancer stem cell population; a method for detecting the presence of said cancer stem cell or cancer stem cell population and for identifying or quantifying the same. The present inventors discovered that highly pure colon cancer stem cells (CSC) can be obtained in a large quantity, and identified two types of states of colon CSCs distinguishable through Lgr5 expression.

Cancer stem cell isolation

An objective of the present invention is to facilitate the acquisition of antibody-producing cells that are infiltrating virus-infected cells, cancer cells, abnormal cells forming a benign hyperplasia, and the like, and to improve the efficiency of the production of antibodies as well as nucleic acids encoding them from the antibody-producing cells. The present inventors discovered that, when cancer tissues comprising infiltrating lymphocytes are transplanted into highly immunodeficient animals that do not have T cells, B cells, and NK cells and further exhibit a low IFN production ability, the differentiation and proliferation of infiltrating lymphocytes are unexpectedly promoted, and the number of plasma cells that produce antibodies recognizing cancer tissues increases dramatically, plasma cells can be separated easily, and antibodies or nucleic acids encoding them can be easily prepared from the plasma cells.

Methods of generating and using antibody-producing cells

Method of producing a nucleic acid encoding an antibody

Growing community of inventors

Singapore, Singapore

Koichi Matsubara