Semicarbazide-cadmium therapy
Encyclopedia
Semicarbazide-cadmium therapy was an experimental cancer therapy that was tested in several clinical trials in Russia during the 1960s. Semicarbazide
is an irreversible inhibitor of semicarbazide-sensitive amine oxidase (SSAO), an enzyme possibly involved in exacerbation of inflammation. Cadmium
is a heavy metal and can also induce apoptosis
.
The first study in humans was an open pilot trial conducted in Russia in 1957-1962. It was also patented in Russia.
(a SSAO-inhibitor) gives the evidence that an inflammatory reaction can be reduced by blocking the enzymatic activity of the enzyme semicarbazide-sensitive amine oxidase (SSAO). SSAO activity was found significantly increased in blood and tissues in some pathological conditions. The enzyme activity has been reported to be elevated in diabetes and cancer. The mean specific activity of SSAO was significantly elevated in the group of patients having prostate cancer with skeletal metastases. Semicarbazide (and SSAO blockers) can reduce inflammatory response and can protect against the progressive vascular complications caused by oxidative stress
. It also can reduce pain. The SSAO inhibitors also appears able to protect endothelial cells against toxic effects of free radicals. Semicarbazide itself is a standard enzyme inhibitor and new SSAO inhibitors are in development.
is a heavy metal and an environmental pollutant. Cadmium is a known carcinogen
. Cadmium exposure has been linked to lung, prostate and renal cancer.. It is not a strong mutagen, but acts as a promoter through mitogenic
effects on gene expression. Cadmium (metallotherapeutic drug, metal-based drug) can induce apoptosis
(programmed tumor cell death) in various cell types.
Semicarbazide
In organic chemistry, semicarbazide is a derivative of urea, where NH2 on one side has been replaced with H2NNH2 hydrazine, yielding H2NNHCNH2.Semicarbazide is used as a detection reagent on thin layer chromatography...
is an irreversible inhibitor of semicarbazide-sensitive amine oxidase (SSAO), an enzyme possibly involved in exacerbation of inflammation. Cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
is a heavy metal and can also induce apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
.
The first study in humans was an open pilot trial conducted in Russia in 1957-1962. It was also patented in Russia.
Method
The method involved the use of the following preparations: semicarbazide hydrochloride, urea, and cadmium halides. Additionally, stable isotopes of gadolinium, as gadolinium oxides, can be used, in addition to other drugs.Semicarbazide
Clinical use of semicarbazideSemicarbazide
In organic chemistry, semicarbazide is a derivative of urea, where NH2 on one side has been replaced with H2NNH2 hydrazine, yielding H2NNHCNH2.Semicarbazide is used as a detection reagent on thin layer chromatography...
(a SSAO-inhibitor) gives the evidence that an inflammatory reaction can be reduced by blocking the enzymatic activity of the enzyme semicarbazide-sensitive amine oxidase (SSAO). SSAO activity was found significantly increased in blood and tissues in some pathological conditions. The enzyme activity has been reported to be elevated in diabetes and cancer. The mean specific activity of SSAO was significantly elevated in the group of patients having prostate cancer with skeletal metastases. Semicarbazide (and SSAO blockers) can reduce inflammatory response and can protect against the progressive vascular complications caused by oxidative stress
Oxidative stress
Oxidative stress represents an imbalance between the production and manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage...
. It also can reduce pain. The SSAO inhibitors also appears able to protect endothelial cells against toxic effects of free radicals. Semicarbazide itself is a standard enzyme inhibitor and new SSAO inhibitors are in development.
Cadmium
CadmiumCadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
is a heavy metal and an environmental pollutant. Cadmium is a known carcinogen
Carcinogen
A carcinogen is any substance, radionuclide, or radiation that is an agent directly involved in causing cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes...
. Cadmium exposure has been linked to lung, prostate and renal cancer.. It is not a strong mutagen, but acts as a promoter through mitogenic
Mitogen
A mitogen is a chemical substance that encourages a cell to commence cell division, triggering mitosis. A mitogen is usually some form of a protein.Mitogenesis is the induction of mitosis, typically via a mitogen....
effects on gene expression. Cadmium (metallotherapeutic drug, metal-based drug) can induce apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
(programmed tumor cell death) in various cell types.