JPS6287526A - Antitumor agent - Google Patents

Abstract

PURPOSE:An antitumor agent, containing an excited semiconductor as an active constituent, capable of acting on tumors to damage tumorous cells and preventing the multiplication and further achieving efficient antitumor effect. CONSTITUTION:An antitumor agent containing a semiconductor excited by X rays, ultraviolet rays, etc., as an active constituent. An inorganic semiconductor, particularly. TiO2, ZnS or SrTiO3 is preferably used as the semiconductor from the viewpoint of stability and influence on the body, etc. In administration, the agent is preferably used with a substance, e.g. hematoporphyrin or monoclonal antibody, etc. The excited semiconductor is capable of preventing the multiplication of the target tumorous cells and achieving efficient antitumor effect.

Description

[Detailed description of the invention] (Industrial application field) TECHNICAL FIELD The present invention relates to antitumor agents.

(Prior Art) At present, methods such as surgery, drug administration, and methods using physical energy are well known as methods for treating malignant tumors. Methods using physical energy include treatments using lasers, radiation, heat, etc., which are used alone or in combination with other treatments.

(Problems to be Solved by the Invention) Furthermore, the present inventors came up with the idea that semiconductors might be able to exert antitumor effects through their reactive power, and as a result of conducting various studies, they arrived at the present invention. .

(Means for Solving the Problems) That is, the gist of the present invention resides in an antitumor agent containing an excited half-four body as an active ingredient.

The present invention will be explained in detail below.

First, the semiconductor in the present invention may be either an inorganic semiconductor or an organic semiconductor. For example, the former is Tl.
O2, ZnO, WO3, 5n02, n203, M2O
3, Fe2O3, 5rTi03, BaTiO3, KTa
In addition to oxides such as O3, ZnS, cas, CdSe
, GaP, GaAs, Si, Ge, etc., and the latter include pyrene, anthracene, phthalocyanine, porphyrin, polyacetylene, polypyrrole, etc. Considering stability, impact on the body, etc., inorganic semiconductors are common, such as TiO2, Zn8%5rTi, 0
3 is preferably used. Their particle size, crystal type, etc. can be appropriately selected depending on the purpose, and they can also be used as a liquid. For example, when TiO2 is used, it is generally anatase type with an average particle size of about 3 microns or less.

To excite the semiconductor, electromagnetic waves such as ultraviolet light,
Light such as visible light or X-rays, gamma rays, etc. with shorter wavelengths are used.

The type of electromagnetic wave and the amount of irradiation are determined in consideration of the type of semiconductor, the method of administration, the type of tumor, etc., but the amount of irradiation needs to be sufficient to excite the semiconductor used.

When administering the antitumor agent according to the present invention, it is preferable to use it together with a substance that has specific affinity for tumor cells. Substances with chemical affinity include, for example, hestoporphyrin derivatives (Hl;
Pages 1-109 (z9yl) o When this HpD is taken into the body, it is more likely to be present in tumor cells than in normal cells.
0 times] and is concentrated with a concentration difference even higher than 0 times.

It has the property of staying for a long time.

For example, when TlO2 is used as a semiconductor.

TiO2 can be given affinity for tumor cells by a chemical modification method that combines the OH groups present on its surface with the carboxyl groups of HpD.

In addition, monoclonal antibodies specific to tumor cells can be cited as substances with immunological affinity, and by using these, it is also possible to selectively reach tumor cells.

For example, by creating a monoclonal antibody that uses a special glycoprotein present on the surface of tumor cells as an antigen and binding it to a liposome encapsulating a semiconductor, the semiconductor of the present invention can be applied to the surface of tumor cells. Selectively take n
When you cool it, you can make fire. In this case, as the semiconductor, for example, one in which the above-mentioned HpD is bonded can also be used.

Administration of the anti-tumor agent can be carried out orally or parenterally, examples of the latter include intravenous or injection into the tumor site. Parenteral administration is generally used, although it varies depending on the site of the tumor.

The dosage is determined appropriately depending on the type and size of the tumor, the type of semiconductor, etc., but is usually about lη-/, 000/
Selected once.

During administration, the above-mentioned affinity substances can be combined and used in order to selectively reach the target tumor. The affinity substance is not limited to the above-mentioned HpD and monoclonal antibodies, and for example, cisplatin (platinum complex) can also be used.

The timing to excite the semiconductor is usually chosen after it reaches the tumor cells. The presence or absence of arrival can also be determined by detecting fluorescence from a semiconductor, HpD, or the like.

The excited semiconductor acts on the tumor, damaging the tumor cells and preventing their growth.

When used in combination with HpD, for example, TlO2 as a semiconductor
When HpD is irradiated with ultraviolet rays or X-rays, HpD itself is also excited, resulting in a cooperative growth-inhibiting effect.

Of course, the antitumor agent according to the present invention can also be used in combination with other treatments such as chemotherapy.

(Example) Hereinafter, the present invention will be further explained in detail with reference to Examples.

Example/The effect of the antitumor agent according to the present invention in culture was determined using human malignant tumor cells and 17 HeLa cells. That is, 0.1% by weight of TiO2 (anatase) powder (average particle size of about 2J) was added to HeLa cell culture medium (MKM medium supplemented with 10% fetal bovine serum), and then the following After irradiation with (1,) or (11), culture was performed.

(1) X-rays 100 rad (11) Ultra-high pressure mercury lamp, 1Q minutes For comparison, a) Control (no TiO2, no irradiation) b)
With TiO2 (θ, /weight ratio), without irradiation c) Ti
Culture was performed in the same manner without O2 and with X-ray irradiation (same as above).

The results are shown in Figure/.

That is, when using the antitumor agent according to the present invention, H
It can be seen that the proliferation of θLa cells is suppressed.

(Effects of the Invention) The antitumor agent according to the present invention can inhibit the proliferation of target tumor cells, and therefore can achieve efficient antitumor effects.

Applicant: Akira Fujishima and 1 other person Representative Patent Attorney Hase - Figure 1

Claims (4)

[Claims] (1) An antitumor agent containing an excited semiconductor as an active ingredient. (2) Claim 1 in which the semiconductor is an inorganic semiconductor
The antitumor agent described in Section 1. (3) The inorganic semiconductor is TiO_2, ZnS or SrTiO
The antitumor agent according to claim 2, which is _3. (4) Claims 1 to 3 in which excitation is performed by electromagnetic waves
The antitumor agent according to any one of Item 3.