JPH05339156A - Selective cytotoxic agent for human tumor cell - Google Patents

Abstract

PURPOSE:To obtain a selective cytotoxic agent having extremely high selectivity to human tumor cells and low side-effects, comprising piericidin A as an active ingredient. CONSTITUTION:A selective cytotoxic agent comprises 2-(10-hydroxy-3,7,9,11- tetramethyl-2,5,7,11-tridecatetraenyl)-5,6-dimethoxy-3-methyl-4-pyridinol (piericidin A) of the formula as an active ingredient. A dose is 0.01-100mg/kg/day calculated as the amount of piericidin A per adult and 0.01-60mg/kg/day per child in the case of oral administration and is preferably 4mg/kg/day in the case of parenteral administration. Piericidin A is a well-known substance isolated from culture strain of Streptomyces mobaraensis as an antibiotic and an insecticidal active substance and has antimicrobial action, inhibitory action on electron transfer system, insecticidal action, hypotensive action, vasodilating action on coronary arteria, differentiation inducing action, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug which selectively shows cytotoxicity to human tumor cells, and more specifically to 2- (10-hydroxy-3,7,9,11- Tetramethyl-2,5,7,11-tridecatetraenyl)
The present invention relates to a selective cytotoxic agent (hereinafter sometimes referred to as "drug") containing -5,6-dimethoxy-3-methyl-4-pyridinol (hereinafter referred to as piericidin A) as an active ingredient.

[0002]

[Chemical 2]

[0003]

2. Description of the Related Art As chemotherapeutic agents for malignant tumors,
Antibiotics (Mitomycin C, Dactinomycin, Doxorubicin, etc.), Plant alkaloids (Vincristine, etc.), Platinum preparations (Cisplatin, Carboplatin, etc.),
Purine antagonists, pyrimidine antagonists, drug-acid antagonists, alkylating agents (chlormethine, cyclophosphamide, thiotepa, etc.), nitrosourea derivatives (carmustine, etc.), hormone agents (megestrol acetate, tamoxifen citrate, etc.), etc. Many drugs have been developed. However, since many of these drugs show cytotoxicity and their selectivity is low, there is a problem that they show cytotoxicity not only to tumor cells but also to normal cells and cause serious side effects. there were.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and its object is to achieve high selective toxicity to human tumor cells, which cannot be achieved by conventional chemotherapeutic agents. It is to provide a drug having few side effects.

[0005]

The selective cytotoxic agent of the present invention is characterized in that it contains piericidin A represented by the following formula as an active ingredient.

[0006]

[Chemical 3]

[0007]

EFFECTS OF THE INVENTION The inventors of the present invention have conducted various exploratory studies on drugs showing low damage to normal cells and selectively showing strong damage to human tumor cells. As a result, the inventors have found that even though Piericidin A is at a low concentration, it is derived from human solid cancer. It was found that they have strong selective cytotoxicity to tumor cells.

[0008] Piericidin A, which is an active ingredient of the drug of the present invention, is a known substance isolated as an antibiotic or insecticidal active substance from a cultured strain of Streptomyces mobaraensis. (Japanese Patent Publication Sho 39-9443, Tamura et al., Ag
ric.Biol.Chem., Vol.27,576 (1963), Yoshida and Takahashi, He
terocycles, Vol.10, 425 (1978)). Piericidin A has also been isolated from a culture of Streptomyces pierisidicus seino (JP-A-50-13218).
3). As its action, an antibacterial action, an electron transfer system inhibiting action, and an insecticidal action of azuki bean weevils (JP-A-50-1321
83), antihypertensive action, coronary artery dilating action (JP-A-59)
-62524), differentiation-inducing action (JP-A-59-4)
No. 6219) is known. As for cytotoxicity, mouse L cells (Pestic.Biochem.Physiol., Vol. 1
0,313 (1979) and mouse lymphocytic leukemia cells (JA
ntibiotics.Vol.40, 149 (1987)) is known. However, no information on cytotoxicity against human tumor cells has been obtained.

The inventors of the present invention have conducted various searches for drugs showing low damage to normal cells and selectively showing strong damage to human tumor cells.
Was found to have strong selective cytotoxicity against human solid tumor-derived tumor cells even at low concentrations.

Although the mechanism of selective cytotoxicity of piericidin A has not yet been fully elucidated, the stage of piericidin A from NAD of the terminal oxidation system in intracellular mitochondria to cytochrome b in mammals and insects It has been shown to inhibit. Therefore, when a normal cell turns into a tumor, the permeability of its cell membrane or intracellular metabolic activity changes, and as a result, Piericidin A is selectively taken up by human tumor cells or detoxified. It seems that it reaches the terminal oxidation system without it and inhibits it. Piericidin A
It can be produced by the method described in JP-B-39-9443 or the method described in JP-A-50-132183.

The drug of the present invention can be used for both oral and parenteral administration, and the dosage form can be selected according to this. In the case of oral administration, it is administered as tablets, powders, granules, soft / hard capsules, and liquids, and in the case of parenteral administration, subcutaneous, intravenous or intramuscular injection of water-soluble suspensions, oily preparations, etc., drip, solids. It may be administered in the form of a suppository or the like as a solid or suspension viscous liquid.

Formulation of the active ingredient of the present invention is carried out according to a conventional method such as surfactants, excipients, lubricants, adjuvants and, if necessary, pharmaceutically acceptable film-forming substances, coating aids, etc. Can be carried out, and specific examples thereof will be given below.

In order to improve the disintegration and dissolution of the drug of the present invention, a surfactant such as Tween 60 and polysorbate is used.
One or more of alcohols represented by 80, esters, polyethylene glycol derivatives, sorbitan fatty acid esters, sulfated fatty alcohols and the like can be added.

As the excipient, for example, sucrose, lactose, starch, crystalline cellulose, mannite, light anhydrous silicic acid, magnesium aluminate, magnesium aluminometasilicate, synthetic aluminum silicate, calcium carbonate,
One kind or two or more kinds of sodium hydrogen carbonate, calcium hydrogen phosphate, carboxymethyl cellulose calcium and the like can be added in combination.

As the lubricant, for example, magnesium stearate, talc, hydrogenated oil and the like can be added alone or in combination of two or more, and salt, saccharin, sugar, mannitol, orange oil can be used as a flavoring agent and a flavoring agent. , Licorice extract,
Sweetening agents such as citric acid, glucose, menthol, eucalyptus oil, malic acid, etc., flavoring agents, coloring agents, preservatives and the like may be contained.

Examples of adjuvants such as suspending agents and wetting agents may include coconut oil, olive oil, sesame oil, peanut oil, calcium lactate, safflower oil, soybean phospholipid and the like.

Further, as a film-forming substance, cellulose acetate phthalate (CAP), and acrylic acid copolymers, polyvinyl derivatives such as dibasic acid monoesters, and the like are methyl acrylate / methacrylic acid copolymers and methacrylics. Examples thereof include methyl acid / methacrylic acid copolymers.

When coating the above-mentioned film-forming substance, a film-forming material is formed by adding a coating aid which is usually used, for example, a plasticizer and various additives for preventing mutual adhesion of chemicals during coating operation. It can improve the properties of the agent and make the coating operation easier. The active ingredient may be microencapsulated using a film-forming substance and then mixed with an excipient or the like to give a dosage form.

The dose of the drug of the present invention is an amount that exerts sufficient selective cytotoxicity on the target human tumor, and is appropriately determined in consideration of the type of tumor, symptoms, administration route, dosage form and the like. However, in general, the amount of the active ingredient pyricidin A is about 0.01 to 100 mg for adults when orally administered.
/ Kg body weight / day, in the range of 0.01-60 mg / kg body weight / day for children, the upper limit is preferably about 40 mg / kg body weight / day. In the case of parenteral administration, the upper limit is about 10 mg / kg body weight / day, preferably about 4 mg / kg body weight / day.

[0020]

[Examples] The present invention will be described in more detail below with reference to formulation examples and test examples. However, the following formulation examples and test examples do not limit the present invention, and do not depart from the gist of the above and the following. All modifications are included in the technical scope of the present invention. Formulation Example 1 (Tablets) One tablet having the following composition was produced according to a conventional method. Formulation Example 2 (Oil injection) An oil injection having the following composition was produced according to a conventional method.

Test Example 1 A cytotoxicity test of piericidin A against tumor cells derived from human solid cancer and normal human cells was carried out. Cell type used Normal cells: Human embryonic skin cells
ll, WS-1 cell) Tumor cell: Human lung carcinoma cell
l, A-549 cells) 10% in Dulbecco's modified Eagle medium (DMEM) manufactured by Gibco
2 × 10 ⁵ cell / ml was added to the medium containing 100 mg / l of fetal bovine serum and 100 mg / l of streptomycin.
Of WS-1 cells and A-549 cells at 5 × 10 ⁵ cells / ml, and culturing at 37 ° C. in 5% CO _{2 for} 24 hours. The medium was replaced with a fresh medium containing Piericidin A at a predetermined concentration, and the cells were further cultured for 24 hours. Cytotoxicity was measured by measuring the uptake of Neutral Red by cells and comparing it with a control. That is, the medium is removed and serum-free DM containing neutral red is added.
EM was put in to incorporate neutral red into the cells. After 3 hours, the medium was removed, 50% ethanol-1% acetic acid was added to extract neutral red to the outside of the cell, and 540 nm
The absorbance was measured. Adriamycin and mitomycin C were used as comparative compounds. The results are shown in Table 1. The cytotoxicity was represented by the concentration IC ₅₀ at which 50% of the neutral red uptake in the control was suppressed and the control was taken.

[0022]

[Table 1]

As is clear from Table 1, the piericidin A of the present invention shows lower cytotoxicity to normal human cells than the comparative compounds adriamycin and mitomycin C, but to human solid cancer-derived tumor cells. Is
It shows cytotoxicity at extremely low concentration compared to the comparative compound,
It can be seen that the selectivity is high. This shows that Bielicidin A has a hitherto unknown effect, that is, a selective cytotoxic effect on human tumor cells.

[0024]

The present invention is configured as described above,
It has become possible to provide a selective cytotoxic agent that has extremely high selectivity for human tumor cells and therefore has few side effects as seen with chemotherapeutic agents.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seio Mimura 1-25-14 Kannondai, Tsukuba-shi, Ibaraki Prefecture Kobe Steel Works Tsukuba Research Area (72) Inventor Yoshimasa Takahara Kannondai, Tsukuba-shi, Ibaraki Prefecture 1-25-14 Stock Company Kobe Steel Works Tsukuba Research Area

Claims (1)

[Claims] 1. A piericidin A (pieri) represented by the following formula:
cidinA) as an active ingredient, a selective cytotoxic agent for human tumor cells. [Chemical 1]