WO2006038527A1

WO2006038527A1 - Antitumor immunostimulant containing extract from pleurotus cornucopiae as active ingredient

Info

Publication number: WO2006038527A1
Application number: PCT/JP2005/018004
Authority: WO
Inventors: Tokushiro Yoshinari; Kazunori Kato
Original assignee: Three B Co., Ltd.
Priority date: 2004-10-01
Filing date: 2005-09-29
Publication date: 2006-04-13
Also published as: JPWO2006038527A1

Abstract

An antitumor immunostimulant containing an extract from Pleurotus cornucopiae as an active ingredient. It has been proved that the extract from Pleurotus cornucopiae suppresses the multiplication of tumor cells, increases the production of immunostimulatory cytokine and suppresses the increase of immunosuppressive T cells. Further, there is provided an immunostimulatory health food, or tumor cell amplification suppressive health food, comprising the extract from Pleurotus cornucopiae.

Description

Specification

Anti-tumor immunostimulant containing tamogi mushroom extract as active ingredient

Technical field

[0001] The present invention relates to an antitumor immunostimulant and an immune-stimulated health food comprising a potato extract as an active ingredient.

Background art

[0002] Various reports have been made on the bioimmunity-stimulating action of mushrooms, and the mechanism of immunostimulation has gradually revealed the difference in physiological activity due to the difference in mushroom species. So far, polysaccharides contained in certain types of mushrooms have been commercialized and used for anti-cancer purposes, but their effects are not always sufficient, and more useful immunostimulants are desired. It was rare.

[0003] In recent years, treatments with drugs for various infectious diseases and cancers have been developed and their usefulness has been found! However, cancer chemotherapy and cancer immunotherapy have also achieved satisfactory results. ,,,. The onset of these diseases is largely due to decreased activity of immunocompetent cells. Therefore, a composition having an immunostimulatory effect on immunocompetent cells is extremely useful for the prevention and treatment of these diseases, and is also important from the viewpoint of maintaining health.

[0004] The biological defense mechanisms by the immune system include innate immunity and acquired immunity. Innate immunity is a mechanism mainly composed of macrophages and leukocytes that eliminates pathogenic bacteria and other patterns by recognizing and preying on them, whereas acquired immunity is a variety of T cells and B cells. It is an immune response that can deal with each foreign antigen. The immune response reacts as powerfully and efficiently as the living body is exposed to the antigen, preventing re-infection of viruses and the like. However, it has been shown that inflammatory tissue damage and autoimmune diseases occur frequently when the immune response is constantly active in the body, and the immune response is negatively controlled in the body. Cells, or suppressor T cells, are involved in maintaining autoimmune tolerance in normal individuals in the normal state.

[0005] Recent studies have shown that naturally occurring inhibitory T cell abnormalities directly cause human autoimmune diseases, inflammatory bowel disease, and allergies. Of this suppressor T cell If the function can be strengthened, it can be expected to control autoimmune diseases, allergies, and immune rejection of transplanted organs.

[0006] On the other hand, it has been shown that suppressor T cells inhibit an effective immune response against tumor cells (cancer cells) generated from self in normal individuals. That is, it is considered that the cells involved in autoimmunity are also tolerant to tumor cells. In fact, experimentally removing inhibitory τ cells from normal individuals induces or enhances the immune response to the tumor and can exert an antitumor effect.

[0007] Inhibitory T cells present in normal individuals are classified as CD25 or GITR (Glucocorticoid-induced TNFR family gene) and FoxP3 gene positive cells contained in the CD4 positive T cell group. Therefore, inhibitory T cells present in lymphoid tissues (spleen, lymph nodes, peripheral blood, bone marrow) in normal individuals can be analyzed with CD4 and CD25, GITR or FoxP3 molecule-positive cells. When the proportion of inhibitory T cells increases in vivo, the immune response to tumors, viruses, pathogenic bacteria, etc. immediately decreases as soon as the individual falls into immune tolerance or immunosuppression.

[0008] Therefore, an immunomodulator capable of suppressing the increase in immunosuppressive T cells is considered useful as an active ingredient of an immunostimulator.

[0009] Prior art document information relating to the present invention includes the following: JP-A-11 302 191 and Asahi Misaki et al., "Chemical properties and anti-polysaccharides of edible mushrooms (Oyster mushrooms, Tamogitake)" Oncology ”, Bulletin of Osaka City University School of Life Sciences, 39th (1991), p. 1-8. Disclosure of the invention

Problems to be solved by the invention

[0010] An object of the present invention is to provide a drug having an immunostimulatory action and a functional food that are extremely safe.

Means for solving the problem

[0011] As a result of searching for mushrooms having an immunostimulatory effect from edible mushrooms produced in Hokkaido, the present inventors have found that an extract of Tamogi mushroom has a high immunostimulatory effect.

[0012] That is, the present invention provides an antitumor immunostimulant comprising a potato extract as an active ingredient. In another aspect, the present invention relates to a tumor cell comprising an extract of rice cake as an active ingredient. A vesicle growth inhibitor is provided. Tumor cells include tumors in the human body, such as cervical cancer, leukemia, lymphoma, myeloma, melanoma, spleen cancer, prostate cancer, head and neck cancer, breast cancer, lung cancer, colon cancer, stomach cancer, esophageal cancer, Ovarian cancer, squamous cell carcinoma, hepatocellular carcinoma, cholangiocarcinoma, mesothelioma and epidermoid carcinoma-derived cells, tumor cells transplanted into experimental animals such as mice, and cells of cell lines derived from human tumors, such as HeLa , MeWo, Hs695T, A137, KATO-III, MKN 45, MKN28, HuH28, Daudi, Ramos, Raji, U937, HS— Sultan, SKM— 1, THP— 1, IM— 9, MM1S, K562, HL60, HSC— 3, HSC— 4, TTn, TE-10, IMR-32, U251, PC-3, LNCaP, DU145, DLD-1, WiDr, SW837, Lul35, IMR-90, A549, SK— OV— 3, SK— Br— 3, A431, RMG-1, MCF-7, MIAPaCa-2, AsPCl, KP-4. In another aspect, the present invention provides an agent for enhancing the production of immunostimulatory site force-in comprising a potato extract as an active ingredient. Examples of immunostimulatory site-in include, for example, interleukin (IL) 1, 2, 3, 4, 5, 6, 7, 12, 15, 18, 21, 23, interferon (IFN) α, j8, γ, Tumor necrosis factor (TNF) α, β. In another aspect, the present invention provides an immunosuppressive sputum cell growth inhibitor comprising a potato extract as an active ingredient. In still another aspect, the present invention provides an immune-stimulated health food comprising a potato extract and a health food for suppressing tumor cell growth.

Brief Description of Drawings

Figure 1 shows the inhibition of HeLa cell growth by the hot water extract of potato.

Fig. 2 shows the inhibition of tumor cell Sarcomal 80 growth by hot water extract of taro. FIG. 3 shows an increase in activated antigen expression of human rod-shaped cells by the extract of hot water from potato. FIG. 4 shows the enhancement of IL-12 production of human rod-like cell force by the hot water extract of potato. FIG. 5 shows the results of FACS analysis of inhibitory T cells in mouse spleen cells.

FIG. 6 shows the ratio of GITR positive inhibitory T cells in the spleen of Sarcomal80 tumor-bearing mice.

FIG. 7 shows the change in tumor volume of Sarcomal 80-transplanted mice that received the hot water extract of potato and other mushrooms.

FIG. 8 shows the mean tumor weight of Sarcomal 80-transplanted mice that received the hot water extract of potato and other mushrooms. FIG. 9 shows the survival rate of Sarcomal 80 transplanted mice fed with hot water extract of potato and other mushrooms.

BEST MODE FOR CARRYING OUT THE INVENTION

[0014] Tamogi mushroom is a mushroom belonging to the genus Oyster mushroom and is widely used for food mainly in Hokkaido. The bamboo shoot extract can be produced by the following method. The bamboo shoots used in the present invention may be artificially cultivated at a factory where natural products can be harvested. The bamboo shoots are preferably used within 2 hours after harvest.

[0015] Extract active ingredients from the harvested bamboo shoots. The extraction is preferably performed by hot water extraction.

For example, the harvested bamboo shoots are put into boiling water 2-30 times, preferably 5-20 times the weight of the bamboo shoots, and stirred while adding steam. Extract the rice cake extract while boiling and stirring for 10 minutes. The obtained extract may be used as it is or may be filtered to remove the solid content. Further, it may be appropriately concentrated using a vacuum concentrator, a freeze concentrator or the like. In order to store the extract for a long period of time, it may be powdered by freeze-drying or spray-drying, for example, by sterilizing at 120 ° C. for 15 minutes after enclosing in the retort pack.

[0016] The rice cake extract obtained as described above suppresses the growth of cell lines derived from human cancers such as HeLa cells, as shown in the Examples below, and is used to suppress sarcoma transplanted into mice. We were able to inhibit growth. In addition, it has been shown that the extract of coconut husk enhances the production of immunostimulatory sites such as IL-12, activates rod cells, and inhibits the appearance of immunosuppressive T cells. It was. These results confirm that the extract of eel paste according to the present invention has immunostimulatory activity and tumor cell growth inhibitory activity.

[0017] The bamboo shoot extract obtained in accordance with the present invention can be used as it is as an immunostimulating health food or a health food for suppressing tumor cell growth. Good. As for the intake, 0.1-lOmlZkgZ day as an extract with a solid content of 2.5%, especially 1. 8- 2. 7mlZkgZ day is appropriate.

[0018] The immunostimulant according to the present invention has advantages such as being non-toxic and having no adverse effect on the living body even when ingested in large amounts, and thus is very suitable for addition to health foods. Yes. [0019] The contents of all patents and references explicitly cited herein are hereby incorporated by reference as part of the present specification. In addition, the contents described in the specification and drawings of Japanese Patent Application No. 2004-290528, which is the application on which the priority of the present application is based, are cited herein as part of this specification.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1

[0021] Preparation of mushroom heat 7k extract

Hot water extracts of various mushrooms were prepared. Each lkg of bamboo shoots, maitake mushrooms, shimeji mushrooms and shitake mushrooms was placed in 5 kg of boiling water, further heated, boiled and stirred for 10 minutes. The obtained extract was concentrated under reduced pressure to obtain 240 ml of a 2.5% solid concentrate. The resulting concentrate was subjected to a retort sterilization treatment at 120 ° C. for 15 minutes to obtain a mushroom hot water extract.

Example 2

[0022] HeLa cell growth inhibitory activity

The hot water extract of bamboo shoots produced in Example 1 was further concentrated under reduced pressure to prepare a triple concentration of bamboo shoot extract, which was used to measure HeLa cell growth inhibitory activity. HeLa cells were seeded in MEM medium in 96-well microplates with 3.7xl0 ³ cell Zwell, and Tamogi salmon extract had final solid concentrations of 1.25%, 2.5%, 2.75% and 3 respectively. Incubated at 37 ° C with 75%. After 12, 24, and 48 hours, the cell number was counted at 450 nm by the MTT method.

[0023] The results are shown in FIG. At 12 and 24 hours after addition of the bamboo shoot extract, the cell number decreased at all concentrations. At 48 hours, the number of cells decreased at 2.5% or higher. In other words, it was revealed that the growth of HeLa cells was suppressed by adding the bamboo shoot extract. As a control, the same experiment was performed on normal cells derived from mouse spleen, but Tamogi salmon extract exerted no influence on the growth of normal cells.

Example 3

[0024] Make 11 weight ^: 11 ¾

The antitumor effect of Sagittarius hot water extract produced in Example 1 against Sa _rcO mal80 It was measured. Sarcomal80 frozen cells (obtained from Tohoku University Institute of Aging Medicine) are rapidly thawed with 37 ° C warm water, added approximately 10 times the amount of physiological saline, and centrifuged (1000 rpm for 5 minutes). The supernatant was removed. After repeating this operation four times, about 3 times the amount of physiological saline was added to the pellet and stirred to obtain a cell solution.

[0025] 0.1 ml of cell solution (about 5 × 10 ⁶ cells) was transplanted into the abdominal cavity of 5 female mice (Sic: ICR), and sacrificed by cervical dislocation 7 days later. The abdomen was disinfected with ethanol, and ascites was collected using a sterile syringe. Ascites collected from each animal force was mixed, and about 5 × 10 ⁶ cells were transplanted subcutaneously into the wind diameter of female mice (Slc: ICR, 5 weeks old, about 18 g).

[0026] In the evaluation experiment of the preventive effect (groups 1 to 3), for 10 days before and 21 days after the transplantation, and in the evaluation experiment of the therapeutic effect (group 4), 21 days after the transplantation, each day. Single test solution was administered orally. The administration was performed by forcibly administering 12 mlZkg of a test solution consisting of a predetermined amount of hot water extract of hot water and purified hydropower into the stomach of the transplanted animal using a metal sonde for mice. The dosage is as shown in the table below.

[0027] [Table 1]

[0028] Tumor volume was measured on days 5, 7, 10, 14, 17, 21, and 22 after transplantation. Tumor volume is

The minor axis (a) and the major axis (b) of the tumor were measured using a caliper, calculated by the following formula, and expressed as an average standard deviation.

Tumor volume (cm ³ ) = 4/3 π a¾ / 2

[0029] The results are shown in FIG. It was shown that the tumor volume increase was significantly suppressed by administration of the hot water extract of Tamogi. In addition, tamogi hot water extract is administered prophylactically. As a result, it was proved that even higher effects were obtained.

Example 4

[0030] r rM ^ J

Induction of human peripheral blood mononuclear cell-derived rod-shaped cells was prepared according to the method described in Kato et al. (K. Kato, et al., J Leukoc Biol, 70: 941-949, 2001). First, 15-20 ml of blood was collected from the left arm vein of a healthy person using a syringe with heparin, and diluted with an equal amount of PBS under aseptic conditions. The same-diluted blood was layered on Lymphosepar 15 ml (manufactured by IBL) prepared in a sterile plastic tube in advance, and centrifuged at 1500 rpm for 30 minutes. After centrifugation, the mononuclear cell layer on Lymphosepar was collected, and the cells were washed twice by centrifugation with PBS. The mononuclear cells were finally diluted in RPMI 1640 medium containing 10% urine fetal serum (manufactured by Sigma), and the cells were added to a 10 cm plastic petri dish and cultured. After 30 minutes at 37 ° C, non-adherent cells (lymphocytes) were removed, and adherent cells (mononuclear cells) were transformed into rod-shaped cell induction medium (RPMI1640 medium, 10% urine fetal serum, 50 ngZml human GM— CSF (manufactured by Osteogenetics) and 50 ng / ml human IL-4 (manufactured by Osteogenetics)) were cultured at 37 ° C for 7 days to induce human mononuclear cell-derived rod cells.

[0031] The induced rod-shaped cells were collected in a plastic tube, and RPMI1640 medium was added to perform centrifugation, and the number of cells was measured. The cell concentration was finally adjusted to 2xl0 ⁵ Zml with RPMI 16 40 medium, 0.5 ml each was added to the 24-well plate, and various mushroom hot water extracts prepared in Example 1 (Tamogi mushroom, maitake, shimeji mushroom) , Shitake) was added at a final concentration of 2%, and cultured at 37 ° C for 24 hours.

[0032] Spider cells stimulated with mushroom hot water extract were collected in a plastic tube, centrifuged and washed with RPMI1640 medium, FITC-labeled anti-human CD45 antibody, PE-labeled anti-human CD86 antibody (both manufactured by eBioscience) 5 μl of each was added, reacted at 4 ° C. for 1 hour, and analyzed for changes in the expression of cell surface antigens using FACS (BD). CD54 and CD86 in rod cells are molecules indispensable for eliciting an immune response, and it is known that an increase in antigen expression indicates the activity state of rod cells. As a result, as shown in FIG. 3, an increase in the expression of CD86 antigen (shift to the right side of the histogram) was confirmed in the rod-shaped cells to which the hot water extract of paddy rice was added as compared to the cells without addition. This expression enhancement is also due to other mushroom extracts. (Maitake, shimeji) was almost unrecognizable. The following table shows changes in expression of CD54 and CD86 antigens on rod cells (analysis with Flowjo software; manufactured by TreeStar).

[0033] [Table 2]

It was confirmed that the expression of CD54 and CD86 antigens in the rod cells was increased by adding the hot water extract of the rice ball, and this effect was significantly higher than that of other mushrooms. Example 5

[0034] IL 12 cows from rod cells.

The various mushroom hot water extracts produced in Example 1 were used to examine the effect of enhancing IL-12 production from human rod-like cells. Interleukin 12 (IL-12) is a type of cytodynamic force produced mainly by rod-like cell force, and is known to be the most important factor for the activity of NK cells and Thl cells. . The production enhancement effect of interleukin 12 (IL-12), which also produces active rod-like cell force, was analyzed by the following method. The cell concentration of the rod-shaped cells induced in the same manner as in Example 4 was finally adjusted to 2xl0 ⁵ Zml with RPMI1640 medium, and 0.5 ml was added to each 24 well plate. For maturation stimulation, CD40 ligand gene transfer by adenovirus (AxCACD40L—FZRGD, 300 particle Z cells) was performed, and various mushroom hot water extracts (Tamogi mushrooms, mitake mushrooms, shimeji mushrooms) It was added at 2% and cultured at 37 ° C for 48 hours.

[0035] The culture solution of rod-shaped cells stimulated with mushroom hot water extract for 48 hours was collected in a plastic tube, and centrifuged at 10,000 rpm for 5 minutes to collect the supernatant. The culture supernatant was diluted 10-fold with PBS, and then the IL-12 content was measured using an ELISA kit (R & D). As a result, 13.0 ± 0. For IngZml production in rod cells not supplemented with mushroom hot water extract, whereas 14.4 ± 0 IL-12 production was enhanced with a significant difference from IngZml. This effect is also effective for other mushrooms (Shitatake: 13. 8 ± 0. IngZmU was also high.

Example 6

[0036] Suppression of splenic fistula Analysis of T cells

Experimental animals were 5 weeks old animals purchased from S1 ICR SPF male mice (Japan SLC Co., Ltd.). The breeding room was maintained at an average temperature of 22 ° C and humidity of 50%. Five million cells of Sarcomal80 cells shown in Example 3 were administered subcutaneously to the thigh of ICR mice using an lml syringe and 26G (Terumo).

[0037] On the same day of transplantation, the test substance tofu-mushroom extract prepared in Example 1 was forcibly administered into the stomach with a metal sonde for mice up to the 21st day every day. As a control group, an equal amount of physiological saline (Otsuka Pharmaceutical Co., Ltd.) was administered. Seven mice were used per group. The tumor system was measured twice a week after transplantation, and the tumor volume was measured until 21 days later. As a result, a significant tumor growth inhibitory effect was observed in the group treated with hot water extract. This result was the same as the growth suppression shown in Example 3, and the antitumor effect was reconfirmed.

[0038] On day 22 after tumor transplantation, all tumor-transplanted mice were euthanized under deep anesthesia, and the spleen was removed from the abdominal cavity. The isolated spleen was loosened in a petri dish filled with a culture solution to obtain a spleen cell solution mainly composed of lymphocytes. After red blood cells in the obtained spleen cells were hemolyzed, the number of cells was measured, and 100,000 cells were placed in a plastic tube.

[0039] The larger the tumor system, the larger the spleen, and the myelinous cells, which are fibroblasts and slightly reddish, were often mixed. Mice treated with the hot water extract of Tamogi had a larger spleen and mild fibroblasts than mice given saline.

[0040] Fluorescent staining of inhibitory T cells in spleen cells was performed as follows. Although 7 mice in each treatment group were analyzed, inhibitory T cells were analyzed using 6 of them. The experiment number of each mouse is as follows.

Group 1: Saline group

151, 152, 153, 154, 155, 157

Group 2: Tamogitake hot water extract administration group

251, 252, 254, 255, 256, 257 [0041] FITC-CD4 (RM4-5; 0.5 μ 1 / reaction, eBioscience), Biotin-uITR (DTA— 1; 0.5 μ 1 / reaction, eBioscience, Avidine— PE (0.2 μ 1 / rea ction, BDpharmingen) and allowed to react for 1 hour at 4 ° C After washing cells with PBS, dead cells were removed with PI staining, and FACScalibur (BD Biosciences) was used. The number of inhibitory T cells was analyzed using Flowjo software (Trister).

[0042] Inhibitory T cells were calculated from the percentage of GITR positive cells in CD4 positive T cells (FITC positive cells). The results are shown in Figs. GITR-positive suppressor T cells were significantly reduced in the tumor-bearing mice group (13.2% ± 3.1%) treated with the extract of hot water extract compared to the tumor-bearing mice treated with saline (33.4% ± 10.6%) Turned out to be.

[0043] From the above results, it was shown that the hot water extract of scallops contains an active substance that can inhibit the appearance of immunosuppressive T cells induced by the cancer-bearing state. This indicates that the bamboo shoot extract is useful as an immunostimulator.

Example 7

[0044] Comparison of preventive pile ulcer effect on meat shark

The prophylactic anti-tumor effect of Sarcomal 80 was measured using the hot water extract of the bamboo shoot and the commercial mushroom extract. As test substances, the hot spring water extract (lots 1 and 2), Agaritas Sengyo-ro Royal and Meshima (registered trademark) Pure PL2.5 produced in Example 1 were used.

[0045] Sarcomal80 frozen cells (TKG0173, obtained from Tohoku University Institute of Aging Medicine) are rapidly thawed with 37 ° C warm water, added with approximately 10 volumes of physiological saline, and centrifuged (1000 rpm Z). And 5 minutes) and the supernatant was removed. After repeating this operation four times, about 3 times the amount of physiological saline was added to the pellet and stirred to obtain a cell solution. 0.1 ml of cell solution (about 5 × 10 ⁶ cells) was transplanted into the abdominal cavity of mice and sacrificed by cervical dislocation 7 days later. The abdomen was disinfected with ethanol, and ascites was collected using a sterile syringe. Ascites fluid collected from each animal was mixed, and about 5 × 10 ⁶ cells were transplanted subcutaneously into the wind diameter portion of the test animal.

[0046] As test animals, 6-week-old female mice (Sic: ICR) were used, 10 in each group, and food and water were freely fed. Test solution once a day for 10 days before tumor transplantation and 35 days after transplantation The solution was administered orally. The administration was carried out by forcibly administering a predetermined amount of hot water extract of hot spring or control mushroom extract and 12 ml Zkg of test solution having purified hydropower into the stomach of transplanted animals using a metal sonde for mice. The dosage is as shown in the table below.

[0047] [Table 3]

[0048] Tumor volume was measured on surviving individuals on the day of the experiment, on days 5, 7, 10, 14, 17, 21, 24, 28, 32 and 36 (end of observation) after transplantation. The tumor volume was calculated by the following formula after measuring the short axis (a) and long axis (b) of the tumor using calipers.

Tumor volume (cm ³ ) = 4/3 π a¾ / 2

[0049] Tumor weight was measured immediately after discovery in the case of death, and the day after the final administration (day 35 after transplantation) in the case of survival. The test animals were euthanized by exsanguination under ether anesthesia, and the tumor in the left inguinal region was excised and weighed. Based on the average value of the tumor weight of each test group, each tumor growth inhibition rate was calculated by the following formula.

Tumor growth inhibition rate (%) = (1—average tumor weight in the treated group Z average tumor weight in the control group) X 10 0

[0050] The survival rate was calculated by the following formula after examining the survival days of the test animals after tumor transplantation.

Survival rate (%) = (mean survival time in treated group Z mean survival time in control group 1) X 100

[0051] A one-way analysis of variance was performed for each parameter (significance level 10%), and if there was a significant difference between groups, Dunnett's multiple comparison test was performed using the mean value (significant water). Associate 5% and 1%).

[0052] The results are shown in Figures 7-9. In the Tamogi hot water extract administration group, the mean value of the tumor volume Although it increased daily, it remained at a lower value than the control group, and after the fifth day after transplantation, it was statistically significantly lower than the control group. The mean tumor weight was 23.4-29.3% of tumor growth suppression compared to the control group, but there was no statistically significant difference. The survival rate was 15. 5 to 21.0%. In addition, the survival time was statistically significant compared to the control group.

[0053] In the agaritas-administered group, the mean value of the tumor volume increased daily, but remained at a lower value than in the control group, and was statistically different from the control group intermittently after the fifth day after transplantation. The value was significantly lower. The mean value of tumor weight was 5.7% of tumor growth inhibition compared to the control group, and no statistically significant difference was observed. The survival rate was 20.6%. In addition, the survival time was statistically significant compared to the control group. In the Mesima (registered trademark) administration group, the mean value of the tumor volume increased daily, but remained at a lower value than the control group, and statistically compared to the control group intermittently after the fifth day after transplantation. The value was significantly lower. The mean tumor weight was 24.6% less tumor growth than the control group, and no statistically significant difference was observed. The survival rate was 8.9%. There was no statistically significant difference in the days of survival compared with the control group.

[0054] From the above, it was confirmed that the prophylactic administration of the extract of hot water of potatoes suppresses tumor growth and prolongs life.

Industrial applicability

[0055] The antitumor immunostimulatory agent of the present invention is useful for suppressing the growth of tumor cells.

Claims

The scope of the claims

[1] An antitumor immunostimulant comprising a potato paste extract as an active ingredient.

[2] An agent for inhibiting tumor cell growth comprising an extract of Tamogi mushroom as an active ingredient.

[3] An agent for enhancing production of immunostimulatory site force-in, comprising tarogi extract as an active ingredient.

[4] An inhibitor of immunosuppressive T cell increase, comprising tamago mushroom extract as an active ingredient.

[5] An immune-stimulated health food consisting of a bamboo shoot extract.

[6] A health food for suppressing tumor cell growth comprising an extract of Tamogi mushroom.

[7] A method of stimulating antitumor immunity in a subject by administering the sesame extract to the subject.

[8] A method of suppressing tumor cell growth in a subject by administering the tamago mushroom extract to the subject.

[9] A method for enhancing the production of immunostimulatory site force-in by administering to a subject a Tamogi mushroom extract.

[10] A method for suppressing an increase in immunosuppressive T cells by administering to a subject a Tamogi mushroom extract.