JPS6048929A - Antineoplastic agent - Google Patents

Abstract

PURPOSE:To provide an antitumor agent containing lipoteichoic acid as an active component. CONSTITUTION:Lipoteichoic acid (LTA) is extracted from the whole bacterial cell of Gram-positive bacteria (e.g. bacterial strain of Streptococcus genus, Micrococcus genus, Lactobacillus genus, Staphylococcus genus, Bacillus genus, etc.), or an cell envelope containing cell wall and cell membrane separated from the cell of the above strain, by conventional extraction process. The objective antitumor agent is prepared by using the LTA as an active component. Since LTA is amphiphatic, soluble in both water and oily solvents and stable, it can be used as an agent for oral or parenteral administration. Dose: 0.1-100mg, preferably 1-20mg for each person.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an antitumor agent containing an acid (hereinafter abbreviated as LTA) as an active ingredient.

LTA is an amphipathic substance that exists in Gram-positive bacteria.
The skeleton structure is mainly polyglycerate phosphate (PGP)
It has a structure in which libido is bonded to a high polymer consisting of chains.

Analysis by electron microscopy using the heptolytin antibody method revealed that libido was bound to one end of the above-mentioned skeleton (PGP).
It has been found that this part binds to the cytoplasmic membrane of the bacterial cell, while the other end penetrates the cell wall and reaches the bacterial surface layer.

Examples include bacterial species such as Staphylococcus and Bacillus. The structure of LTA that each has may partially arise between bacterial species between these wings and within each wing.

That is, it is known that, for example, products with slightly different PGP chain lengths (25 to 30), the number and manner of galactose and glucose bonds, etc. can be obtained.

However, these partial differences are not reflected in the essential biological and immunological properties, and it is known that the libido portion is responsible for these essential properties.

Therefore, in the present invention, LTA derived from any Gram-positive bacterial species or strain can be used as long as it has anti-lung tumor activity.

For example, Streptococcus biogenes (S*).

The composition ratio of LTA obtained from pyogenem is 1 mole of glycerol to 5. Phosphoric acid 0.
82, glucose 0.05. The fatty acid content is 0.012.

Examples of strains having such T and TA that can be used in the present invention are as follows.

8treptoeoccus faecalispyo
genC1+ utans actis t equisimilis (FIRM-P 405
9) sanguis 8 tapbylococcus aureusepi
dermidis T, acrobacillus plantarum I
fermeotum z casei TJisteria monocytoge, nts. The production of LTA from these strains was carried out by Maskowitz
method (J, Bacteriol, 911220
Beachey et al.'s method (Infect, Immun, *2 L61g-6) with some modifications to 0-2204)
25), whole bacterial cells or cell envelopes containing pre-separated cell walls and cytoplasmic membranes (
0ell envelope ).

Reference example.

5treptococcus pyogenps 8
V strain (ATOO21059) was disrupted and the cell envelope fraction obtained by centrifugation was separated into 10 μg (dry til).
/ml in distilled water. To this was added an equal amount of 95% phenol, and extraction was performed at 4° C. to room temperature for 1 hour with slow stirring. After centrifugation at 18,000Xf for 30 minutes, the aqueous layer was separated. The same amount of distilled water was added to the remaining phenol layer and the same extraction was performed twice. The resulting aqueous layer was combined with the previous aqueous layer and dialyzed against distilled water for 3 days (
The distilled water was exchanged 6 times) and then freeze-dried to obtain a crude LTA fraction.

This crude LTA fraction was sown in 0.2M ammonium acetate.
i (dry type it) / me ratio, 5ep
Added to a barose 6B column (Pharmacia, Sweden, column: 2.6φX 87 cm),
Purification was performed by gel filtration using 0.2M ammonium acetate. As an indicator of LTA, after 8RBO sensitization, anti-PG
Precipitation reaction with P serum and colorimetric determination of phosphorus were used.

The LTA thus obtained has an excellent antitumor effect as shown in the Examples below, and has low toxicity (in an acute toxicity test using mice, there was no death even after administration of about 2f1 kg).
It does not have the pyrogenicity and shock death-inducing effects of ribopolysaccharide, which is a bacterial cell component of gram-negative bacteria, and 8c
Regarding the hwartzman reaction, it does not occur unless the amount is much larger (100 to 500 μ?) than that of ribopolysaccharide.

Since LTA is amphipathic, soluble and stable in both water and oily solvents, it can be used as any oral or parenteral drug by conventional formulation methods.

Generally 01-100q for humans, preferably 1-20η
Administered with good antitumor effect.

Example I Effect on Meth A nodular type 2 x 10' Meth A fibrosarcoma cells per group 5
BALB/c mice (6 appropriate ages, 1 female, Charles River, Shizuoka, Japan) were transplanted into the abdomen, and from the next day onwards, once a day for 4 consecutive days, a 0.2 saline solution of LTA obtained in the reference example was injected into the abdomen.
d was administered intraperitoneally. As a control, saline solution 0.
A 2-dose group was used.

The antitumor activity is determined by the size of the tumor mass over time.^1
1. Measure the ``m'a'' and calculate the ratio of the 5 LT administration group and the control group (
This was done by calculating the growth rate (light damage rate).

The results are shown in FIG. 1, and the antitumor effect was remarkable in the LTAI Oμm administration group 22 days after transplantation.

Example 2' Effect on MethA ascites type Using the same mouse as in Example 1, 2 x 105 MethA were intraperitoneally administered.
thλf ibroaarcoma cells were transplanted, and the therapeutic effect of LTA obtained in the reference example was examined in the same manner as in Example 1. Efficacy was evaluated based on survival up to 4ell and survival days. The results are shown in Figure 2.

Note that the mice that were alive on day 40 in the T, Tλ1011f administration group and 50ity administration group were still alive even after 60 days.

Example 3 Effect of Lacto on Meth A nodule type
The results of an antitumor experiment conducted in the same manner as in Example 1 using T and T individuals extracted from Bacillus plantaum according to the reference example are shown in Figure 3.

[Brief explanation of the drawing]

Figures 1 to 3 are graphs showing the antitumor effects of LTA in Examples 1 to 3, respectively. 71

Claims (1)

[Claims] Antitumor agent containing riboticic acid as an active ingredient