Self-assembled Transition Metal Coordination Frameworks of ...

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1.3.1.1. Anticancer drugs-A briefreport
Cancer chemotherapy uses compounds that can differentiate to some degree
between normal tissue cells and cancer cells. Mechlorethamine, a derivative of the
chemical warfare agent nitrogen mustard, was first used in the 1940s in the treatment
of cancer and was shown to be effective in treating lymphomas. Since then, many
antineoplastic drugs have been developed and used with much success. Because
cancer cells are similar to normal human cells, the anticancer agents are generally
toxic to normal cells and can cause numerous side effects, some of which are life
threatening. These adverse effects may require that the drug dosage be reduced or the
antineoplastic drug regimen be changed to make the drug tolerable to the patient [86].
Alkylating agents were the first anticancer drugs used, and, despite their
hazards, they remain a cornerstone of anticancer therapy. Some examples of
alkylating agents are nitrogen mustards (chlorambucil and cyclophosphamide),
cisplatin, nitrosoureas (carmustine, lomustine, and semustine), alkylsulfonates
(busulfan), ethyleneimines (thiotepa) and triazines (dacarbazine). These chemical
agents are highly reactive and bind to certain chemical groups (phosphate, amino,
sulfliydryl, hydroxyl, and imidazole groups) commonly found in nucleic acids and
other macromolecules. These agents bring about changes in the deoxyribonucleic acid
(DNA) and ribonucleic acid (RNA) of both cancerous and normal cells. The result is
that the nucleic acid will not be replicated. Either the altered DNA will be unable to
carry out the functions of the cell, resulting in cell death (cytotoxicity), or the altered
DNA will change the cell characteristics, resulting in an altered cell (mutagenic
change). This change may result in the ability or tendency to produce cancerous cells
(carcinogenicity). Normal cells may also be affected and become cancer cells.
Alkylating agents have found use in the treatment of lymphoma, leukemia, testicular
cancer, melanoma, brain cancer, and breast cancer. They are most often used in
combination with other anticancer drugs [86].
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