JPH0460969B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-cancer substance sustained-release embolic agent, and more specifically, it can be suitably used in cancer or tumor treatment and diagnosis methods, such as vasoocclusive therapy or puncture therapy. The present invention relates to an anti-cancer substance sustained-release embolic agent.

In recent years, vascular occlusion therapy has been increasingly recognized as an effective means of treating liver cancer, breast cancer, and the like. Vascular occlusion therapy involves the tip of a vascular catheter reaching the feeding artery to the cancer or tumor tissue, and an occluding substance injected from the other end to occlude the feeding artery and stop blood flow. The purpose is to cut off nutritional supply to the tissues and cause necrosis of these tissues. It has been reported that a wound protection material on which blood coagulation factors and thrombin are immobilized, which was previously proposed by the applicant (Japanese Patent Application Laid-Open No. 135214/1984), can be effectively used as an occlusive substance used in vascular occlusion therapy. However, this therapy has the disadvantage that it cannot be used concurrently with chemotherapy, which is an effective means of treating cancer or tumors. In other words, after vascular occlusion therapy, even if an anticancer substance is administered orally or by injection, the feeding artery is occluded, so it can no longer reach the cancer or tumor tissue, and the administration is meaningless. Become. Therefore, when administering vascular occlusion therapy, a two-step method is used, either by abandoning chemotherapy or by injecting an anticancer substance through a vascular catheter before occlusion. However, the amount of anticancer substances injected in this method is not sufficient, and because they are usually injected in the form of a solution and the feeding artery has not yet been occluded, the anticancer substance is only available for a very short period of time. However, it is difficult to expect an effect because it will spread to areas other than the target cancer or tumor tissue.
As described above, the problem with vasoocclusive therapy, that is, the inability to concurrently use chemotherapy, remains unresolved.

On the other hand, along with vascular occlusion therapy, puncture is a therapy that is expected to be a new cancer treatment method. Puncture originally refers to inserting a hollow needle into the body to suck out internal fluid, but the puncture method referred to here particularly refers to methods for examining and treating cancer or tumor tissue.

The testing method generally refers to what is called a puncture biopsy method, which is a method of collecting tissue to be tested from a living body and testing it by scraping tissue that is thought to be cancer or tumor with the tip of a needle. The tissue attached to the needle tip is taken out of the body and examined. It has been pointed out that a problem with this needle biopsy method is that there is a risk that cancer or tumor tissue attached to the needle tip may be scattered onto other normal tissue when the needle is removed. No countermeasures have been taken. It has been pointed out that another problem is that bleeding tends to occur and it is often difficult to stop the bleeding. In other words, unlike vascular occlusion therapy, which involves inserting a catheter through a blood vessel, the puncture method uses a needle to reach the target tissue directly from the body surface, which results in bleeding from the area injured by the needle. . If the injured area is normal, even if bleeding occurs, it will stop spontaneously, the injured blood vessel will be repaired in a relatively short period of time, and there will be no adverse effects after the puncture procedure. However, when puncturing cancer or tumor tissue, typically
Not only the cancer or tumor tissue itself, but also nearby tissues often have insufficient hemostatic ability and ability to repair damaged blood vessels, resulting in increased bleeding tendency, difficulty in hemostasis, and the possibility of large amounts of bleeding. In such cases, the patient may have no choice but to abandon the puncture procedure. In particular, puncturing the pancreas is currently not commonly performed due to bleeding. Therefore, when performing puncture, hemostasis is a major problem, and it is often necessary to remove the needle while stopping the bleeding. The method of hemostasis in this case is usually to remove the needle while gradually injecting an aqueous solution of thrombin, but thrombin itself has insufficient hemostasis ability, and thrombin is in liquid form. Hemostasis has not been achieved satisfactorily because the bleeding tends to flow from the area requiring repair to other areas. On the other hand, the term "therapeutic method" refers to a method of directly injecting an anti-cancer biological substance onto a target cancer or tumor tissue through a puncture needle. Currently, when injecting drugs through a puncture needle, the puncture needle used is usually 19G or more.
Because it is extremely thin, about 23G, it is only used to inject solutions such as antibiotics. However, when an anticancer substance is injected in the form of a solution, sufficient effects cannot be expected because it immediately flows out to areas other than the target tissue and the significance of direct local administration is lost. For this reason, it is possible to spray on the target tissue and near the puncture needle path through a puncture needle with a diameter that is normally used.
There is a long-awaited demand for a preparation that can adhere to the area where it is sprayed and remain there for a long time, allowing sustained release of anticancer substances.

In view of the above-mentioned current situation, the present inventors have proposed that when used in vascular occlusion therapy, the present inventors can rapidly occlude blood vessels.
It can be performed reliably and has the ability to effectively cause anti-cancer substances to act on cancer or tumor tissue for a long time, and when used for puncture, it can quickly and reliably prevent bleeding during the procedure. It can suppress and repair damaged blood vessels at an early stage, and is anti-cancer not only for the cancer or tumor tissue itself but also for cancer or tumor tissue that is likely to be dispersed near the puncture needle route during the biopsy procedure. As a result of intensive research with the aim of developing a drug that has the ability to effectively cause cancer-causing substances to act for a long period of time, surprisingly, a structure immobilized with an anti-cancer substance and a blood coagulant was found to be effective against blood vessels. The fact that it has excellent occlusion ability, hemostasis ability, and damaged blood vessel repair ability.Furthermore, when it is injected from outside the body and reaches the body, it quickly attaches and stays on the cancer or tumor tissue or nearby areas. The present invention was achieved based on the discovery that anticancer substances are not washed away by blood or body fluids and that anticancer substances are sustainedly released over a long period of time.

That is, the present invention provides a structure in which an anticancer substance and a blood coagulant are immobilized on a structure made of a non-bioabsorbable substance and having a shape such as a fiber aggregate, sponge, powder, monofilament, film, or microcapsule. It is an anti-cancer biological slow-release embolic agent.

In the present invention, an embolic agent refers to a preparation that is injected into a blood vessel to stop blood flow, and a preparation that fills a damaged area of a blood vessel to stop bleeding and repair the damaged blood vessel. Since it is necessary to quickly pass through the puncture needle, it is preferable that the material can be finely suspended in a medium such as water.

In the present invention, the material constituting the structure should be a material that will not be absorbed by the living body after administration, since sustained release of anticancer substances over a long period of time is desired. needed,
In the present invention, for example, synthetic polymers such as silicone, polyester, polyamide, polyurethane, polyacrylonitrile, polyacrylamide, polyacrylic acid ester, polyethylene, polypropylene, polyvinyl chloride, silicone, polyvinyl alcohol, cellulose such as cotton, hemp, pulp, etc. , regenerated cellulose obtained by viscose method, cuprammonium method, cellulose derivatives such as ethyl cellulose, cellulose acetate, silk, etc. Among them, silicone and cellulose derivatives are preferably used because of their biotoxicity.

The anticancer substance as used in the present invention means a substance generally called an anticancer agent, an anticancer agent, or an antitumor agent, and a substance generally called an immunopreparative or an immunostimulant, and examples of the former substance include, for example. Nitrogen mustard, nitromine, chlorambucil, cyclophosphamide, melphalan, uracil mustard, mannomustine, dopan,
BCNU, triethylenemelamine, thio-TEPA,
Aza-TEPA, Trenimon, Improquion,
Alkylating agents such as busulfan, dimethylmyleran, piposulfan, ethoglucide, epoxypropidine, epoxypiperazine, hexamethylmelamine, dibromomannitol, pipoproman, leaf powder, aminopterin, methotrexate,
Antimetabolites such as guanine, 8-azaganine, 6-mercaptopurine, azathioprine, uracil, 5-fluorouracil, cytarabine, azaserine, diazomycin, actinomycin D, sacromycin, mitomycin C, daunomycin, bleomycin, chromomycin, cardinophilin, etc. antibiotics, synthetic agents such as 5-HP, IQ-1, plant ingredients such as thioteba, cyclophosphamide, doxorubicin, daunorubicin, neocarcinostane, Hg-hematoporphyrin,
Co-protoporphyrin, stilbestrol, hydroxyurea, procarbazine, methylglyoxal-bis-guanylhydrazone, L-
Examples include asparaginase, and these may be used alone or in combination of two or more, with one type of alkylating agent and one type of antimetabolite being used.
A common method is to select one type from seeds and antibiotics and use them in combination.
- Triple combinations of fluorouracil, mitomycin or bleomycin are particularly common. Examples of the latter substances include chimic hormone and its related substances, BCG, cell wall skeleton and its methanol-insoluble fraction, bacteria and bacterial components such as Corynebacterium pulpum and OK-432, pisibanil, reentinan, SPG mannan, Examples include polysaccharides such as levan and glucan, muramyldipept and its derivatives, levamisole, bestatin, isoprinosine, NPT15392, azimecline, transfer factor, lymphokine, immunoRNA, interferon and its inducer, and vaccines such as Maruyama vaccine. Each of these may be used alone or in combination of two or more, but it is common to use them in combination with the above-mentioned anticancer agents or substances called anticancer agents or antitumor agents.

The blood coagulant used in the present invention includes, for example, blood coagulation factor,
Examples include factor factor, factor 1, factor 1, factor 1, factor 1, factor 1, factor XI, factor XII, factor 1, prekallikrene, high molecular weight kininogen, and thrombin. These can be used alone or in combination of two or more. In the present invention, blood coagulation factor (hereinafter abbreviated as F) and thrombin are particularly preferably used. F is called a fibrin stabilizing factor, and is a factor that promotes the production of stabilized fibrin due to isopeptide bonds between fibrin molecules. F is isolated from the blood or placenta of humans, cows, etc., but when applied to humans, it is preferable to use human-derived F. Thrombin is a proteolytic enzyme that can convert fibrinogen to fibrin. Thrombin is isolated from the blood of humans, cows, pigs, etc., but when applied to humans, it is preferable to use human thrombin.

The anticancer substance and blood coagulant used in the present invention are:
binding or adsorption to the structure;
Alternatively, it can be immobilized by encapsulating it. Attachment of anti-cancer substances and blood coagulants to the structures has been described, for example, by O. Zaborsky,
Conventionally known covalent bonding and ionic bonding methods such as those described in “Immobilized Enzymes” CRC Press.1973 can be used, and physical adsorption and encapsulation methods can also be used for adsorption. In addition, in order to encapsulate the structure, a method of microcapsulating the structure using a material constituting the structure as an outer wall using a known microencapsulation method can be adopted.

When producing the embolic agent of the present invention, an anticancer substance and a blood coagulant can be bound to the structure, for example, in the following manner. In other words, when an anticancer substance or a blood coagulant has a functional group capable of forming a covalent bond or an ionic bond, such as an amino group or a carboxyl group, a solution containing these functional groups can form a covalent bond or an ionic bond. By treating a structure having a functional group capable of ionically bonding, it is possible to perform immobilization through desired bonding. In addition, in this case, if the structure has no or only a few functional groups that can form a covalent bond or ion bond with the functional groups of the anti-cancer substance or blood coagulant, those functional groups are added to the structure in advance. After introducing the groups by chemical reaction, anticancer substances and blood clotting agents can be attached to the structure. If the anti-cancer substance or blood coagulant does not have a functional group, it is possible to use it after introducing a functional group through a chemical reaction as in the case described above, but in many cases this is not possible. This method is not preferably employed because the chemical reaction would damage the properties of the anticancer substance or blood coagulant as a drug. In addition, when making a covalent bond, dicyclohexyl carbodiimide,
Preferably, a dehydration condensation agent such as 1-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide-meth-P-toluenesulfonate is used.

Furthermore, when producing the embolic agent of the present invention, an anticancer substance and a blood coagulant can be adsorbed onto a structure by a physical adsorption method, envelopment, or the like as follows. That is, by dissolving or suspending an anticancer substance and a blood coagulant in a solvent that can wet the structure, and treating the structure with this solution, the anticancer substance and blood coagulant can be physically adsorbed. can. The entrapment method is a method in which anticancer substances and blood coagulants are encapsulated in a fine gel lattice so that they cannot be released. This adsorption method and envelopment method are effective for any combination of anticancer substances, blood coagulants, and structures, and are preferably adopted in the present invention because they are simple and rarely impair the properties as a drug. .

In order to produce the embolic agent of the present invention, in addition to the method of binding or adsorbing an anticancer substance and a blood coagulant to a structure as described above, first, the anticancer substance and the blood coagulant are added to the material itself before being processed into a structure. It can also be manufactured by combining or adsorbing the anti-cancer substance and the blood coagulant, and then processing the material to which the anti-cancer substance and the blood coagulant are combined or adsorbed into a structure. For example, the embolic agent of the present invention can be produced by obtaining a structure using a polymeric substance in which an anticancer substance is bound or adsorbed in advance.

The anticancer substance and the blood coagulant may be immobilized simultaneously by any of the above methods, or the anticancer substance may be immobilized first and then the blood coagulant may be immobilized, The opposite may be true.

When producing the embolus of the present invention, in addition to anticancer substances and blood coagulants, protease inhibitors such as antiplasmin, albumin, and _α2 -macroglobulin, and blood serum substances such as ceruloplasmin, haptoglobin, and cold insoluble globulin are used. Proteins, phaibronectin, antibiotic substances, etc. can be immobilized on the structure. Antiplasmin is an inhibitor of plasmin, which is a fibrinolytic enzyme, and therefore exerts its effect by inhibiting plasmin. In the present invention, as antiplasmin, for example, ε-aminocaproic acid, tranexamic acid, etc. are preferably used.

The embolic agent of the present invention is preferably used in the treatment of cancer or tumors, and is particularly preferably used in vascular occlusion methods, puncture methods, and the like.

The embolic agent of the present invention can be applied to vascular occlusion therapy by, for example, passing the tip of a vascular catheter through a blood vessel to the feeding artery to the target cancer or tumor tissue, and suspending the embolic agent in physiological saline or the like from the other end. It is made by injecting. At this time, a portion of the embolic agent reaches the target tissue and its neighboring tissues, adheres to the target tissue, and remains there, and a portion remains inside the feeding blood vessel, quickly occluding the blood vessel. Also, occluded blood vessels do not recanalize. Furthermore, the embolic agent that remains on the target tissue, its neighboring tissue, and the vascular occlusion acts as a sustained release agent for anticancer substances, and the anticancer substance is sustainedly released from this agent and localized to the cancer or tumor tissue. It acts over a long period of time to accelerate and ensure necrosis.
This means that when the embolic agent of the present invention is used, it is possible to perform vascular occlusion therapy quickly and accurately, and that the embolic agent of the present invention acts as a sustained release agent for anticancer substances. This means that chemotherapy, which could not be done in the past, can now be done in parallel.

Application of the embolic agent of the present invention to the puncture method is, for example, after injecting a required amount of embolic agent suspended in physiological saline through a puncture needle that has reached the target cancer or tumor tissue, and then This is done by removing the needle while gradually injecting this suspension.
This allows the embolic agent to be dispersed onto the target tissue and the tissue near the path of the puncture needle and remains attached to the site. The embolic agent that remains on the target tissue immediately stops bleeding and repairs the vascular damage site, while also acting as a sustained release agent for anti-cancer substances, which is effective against cancer or tumor tissue for a long time. It acts on On the other hand, the embolic agent injected at the time of needle removal, dispersed and adhered to the tissue near the puncture needle path, immediately suppresses bleeding from the damaged area of the nearby blood vessel, repairs it, and disperses it around the needle path. It acts effectively against cancer or tumor tissue for a long time.

As described above, the embolic agent of the present invention is used in procedures such as vascular occlusion therapy and puncture, and has both excellent performance as an embolic agent and performance as a sustained release agent for anticancer substances.

Furthermore, the embolic agent of the present invention exhibits great effects even when used simply as an anticancer substance sustained release agent.
In other words, even if a conventional sustained-release agent for an anticancer substance is administered locally by spraying it onto the exposed cancerous tissue through incisional surgery, the sustained-release agent may be administered to the blood,
Since it is a body fluid, it immediately washes away from the local area after being sprayed, making it difficult to expect an effect, but if the embolic agent of the present invention is administered in the same way, it will not stick to the local area immediately and will not wash away.

The present invention will be explained in more detail with reference to Examples below.

Example 1 200 mg of a nylon sponge cut into approximately 500 μ pieces was dissolved in 4 ml of water with 1 bottle of a fibrogamine aqueous solution [Human F concentrated dry preparation (manufactured by Hoechst)]. ] 4 ml, physiological saline solution of thrombin [1 bottle of concentrated dry human thrombin preparation (Midori Juji) dissolved in 5 ml of physiological saline. ]
4ml and mitomycin C aqueous solution [20mg/4ml]
After immersing in 4 ml of the mixed solution for 5 minutes at room temperature, -30
Freeze-drying was performed at ℃ for 15 hours to obtain an immobilized nylon sponge on which F, thrombin, and mitomycin C were immobilized.

On the other hand, make a loop using a 34 cm Siriyun medical tube with an inner diameter of 4 mm, and place it in a room at 2°C and add 2 ml of ACD preserved blood to 10 wt% aqueous solution of Cacl ₂ .
ml, and then 20 mg of the previously prepared immobilized nylon sponge was added, followed by rotation at 16 revolutions/min on a rotary plate with an inclination of 23 degrees. One minute after the start of rotation, formation of a clot was observed in the blood. Stop the rotation at this point,
1 hour after stopping, paper disk (manufactured by Toyo Seisakusho, paper disk for anti-resistant substance testing, diameter 8 mm)
Thoroughly immerse or adhere to the blood or clot in the loop, use this as a sample, and use it as a test bacterium.
Using Bacillus Subtilis ATCC6633, the size of the inhibition circle produced in the cylindrical plate method was determined, and the blood concentration of mitomycin C at 1 hour was determined from the size of the inhibition circle, and was found to be 10 μg/mg. Similarly, 5th hour, 10th hour, 24th hour, 1.5 days, 2
Blood concentrations were determined on day 3 and day 3, respectively.
15μg/mg, 21μg/mg, 41μg/mg, 82μg/mg,
They were 112 μg/mg and 198 μg/mg.

Comparative Example 1 Immobilized nylon sponge obtained in the same manner as in Example 1 except that F and thrombin were not used.
A blood coagulation test using a rotating loop similar to that used in Example 1 and measurement of blood concentration of mitomycin using 20 mg showed that no clot formation was observed even after 3 hours had passed after the start of rotation. The blood concentration of C was 600 μg/ml. This result shows that most of mitomycin C is released into the blood within 30 hours, meaning that it does not have sustained release properties.

Example 2 Beads made of polyethylene terephthalate (particle size: approximately 250 microns) were immersed in a mixed solution consisting of a 10% polyethyleneimine aqueous solution and 5 times the volume of methanol, and left at room temperature for 30 minutes. Next, a methanol solution of 5% by weight dicyclohexylcarbodiimide in an amount twice the volume of polyethyleneimine was added, and the mixture was further left at room temperature for 2 hours. After being left to stand, the beads were washed with methanol and then dried. Next, the polyethyleneimine-treated beads were immersed in an acetone solution containing 4% by weight of methyl vinyl ether-maleic anhydride copolymer, left at room temperature for 2 hours, and then washed with acetone. The washed beads were then dried, 200 mg of them were weighed, and this was added to a fibrogamine aqueous solution [1 bottle of Human F concentrated dry preparation (manufactured by Hoechst) dissolved in 8 ml of water. ] 4 ml at room temperature for 3 minutes, and then freeze-dried at -30°C for 15 hours. Next, this material was immersed for 5 minutes at room temperature in a suspension of 25 mg of 5-fluorouracil suspended in 4 ml of dimethylformamide, and then freeze-dried at -30°C for 15 hours.
Immobilized polyethylene terephthalate beads on which 5-fluorouracil and 5-fluorouracil were immobilized were obtained.
Using 20 mg of this product, a blood coagulation test using a rotating loop was conducted in the same manner as in Example 1, and after the start of rotation,
Formation of a clot was observed in 1.5 minutes. At this point, the rotation was stopped, and 50 μg of blood or clots were sampled at 5 hours, 10 hours, 24 hours, 1.5 days, 2 days, and 3 days after stopping, and after freeze-drying each sample, Using a mixture of sodium hydroxide and water as the absorption liquid, the amount of fluorine contained in each sample was determined using the oxygen flask combustion method.
The weight of fluorouracil was measured and the blood concentration of 5-fluorouracil at each sampling time was determined to be 3.0 μg/mg, 5.0 μg/mg, and 9.5 μg, respectively.
g/mg, 20.0μg/mg, 29.5μg/mg, 58.5μg/mg
It was hot.

Example 3 F and 5-
Immobilized nylon 6 beads on which fluorouracil was immobilized were obtained. When 20 mg of this product was used to conduct a coagulation test and blood concentration measurement in the same manner as in Example 1, the fluidity of the blood in the tube where the clot had been formed was lost 1 minute after the start of rotation. Also, 1st hour, 5th hour, 10th hour, 24th hour, 1.5th day,
The concentration of 5-fluorouracil in the blood on the 2nd and 30th day was 1.5 μg/ml and 3.5 μg/ml, respectively.
ml, 5.5μg/ml, 10.5μg/ml, 20.5μg/ml,
They were 30.0 μg/ml and 58.5 μg/ml.

Example 4 Nylon 6 taffeta was cut into 500 micron squares, and 200 mg of bleomycin and 1-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide were added to 10 ml of a physiological saline solution of thrombin (1 bottle dissolved in 10 ml). After immersing in a solution containing 20 mg of metho-p-toluenesulfonate at room temperature for 5 minutes, freeze-drying was performed at -30°C for 15 hours to obtain immobilized nylon 6 taffeta on which thrombin and bleomycin were immobilized. . Using 20 mg of this product, a blood coagulation test using a rotating loop and measurement of the blood concentration of bleomycin were performed in the same manner as in Example 1. As a result, formation of a clot was observed 1 minute after the start of rotation, and at this point, 1 hour after stopping rotation,
The blood concentrations of bleomycin at the 5th hour, 10th hour, 24th hour, 1.5th day, 2nd day, and 3rd day were 2.0μg/mg, 4.0μg/mg, 6.0μg/mg, and 10.5μ, respectively.
g/mg, 21.5μg/mg, 31.0μg/mg, 59.5μg/mg
It was hot.

Claims (1)

[Claims] 1 Fiber aggregate made from non-bioabsorbable substances,
sponge, powder, monofilament, film,
An anticancer substance sustained-release embolic agent, which is an anticancer substance and a blood coagulant immobilized in a structure having a shape such as a microcapsule.