alkylating agents


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Related to alkylating agents: Antimetabolites

alkylating agents

 [al´kĭ-lāt-ing]
a group of synthetic compounds containing alkyl groups that combine readily with other molecules. Their action seems to be chiefly on the DNA in the nucleus of the cell, so that they are cell cycle phase nonspecific. They cross-link the strands of DNA, preventing its replication and the transcription of RNA; the major site of action is on the base guanine. They are primarily used in chemotherapy of cancer (see antineoplastic therapy). However, they do not damage malignant cells selectively, but also have a toxic action on normal cells; all killing occurs primarily in rapidly proliferating tissue. Locally they cause blistering of the skin and damage to the eyes and respiratory tract. Systemic toxic effects are nausea and vomiting, reduction in both leukocytes and erythrocytes, hemorrhagic tendencies, amenorrhea or impaired spermatogenesis, damage to the intestinal mucosa, and alopecia. Among the agents of this group used in therapy are busulfan, cyclophosphamide, ifosfamide, and thiotepa; the nitrogen mustardschlorambucil, melphalan, and mechlorethamine; and the nitrosoureascarmustine, lomustine, and streptozocin. They may be carcinogenic in humans; some have been linked to bladder cancer and acute leukemia. However, the major benefits obtained in treating diseases such as lymphoma, Hodgkin's disease, breast cancer, and multiple myeloma far outweigh the risks of developing a second malignancy.

alkylating agents

agents that react with groups such as amino [NH2 ], carboxyl [COOH], hydroxyl [OH] and phosphate [PO4 ] groups, and replace them with alkyl groups, such as CH3, CH2 CH3 groups. They may act as MUTAGENS or as ANTIMICROBIAL AGENTS.
References in periodicals archive ?
Many treatment modalities for cancer are gonadotoxic * Chemotherapy - Alkylating agents * Radiation therapy * Surgery * Unknown effect of large number of new agents, including antibodies and targeted therapy - Patients and families want to be informed about impact of treatment on fertility and preservation options at the time of diagnosis Which groups should be targeted by fertility preservation strategies?
5% Table 3 Immunosuppressive drugs Table 3 Class Examples Antimetabolites Azathioprine Methotrexate Mycophenolate mofetil Alkylating agents Cyclophosphamide Chlorambucil Antibiotics Cyclosporine Tacromimus Rapamycin Dapsone Adjuvants Bromocriptine Ketoconazole Colchicine
Alkylating agents are utilized in cases showing insufficient treatment response to antimetabolites or combination therapy.
Alkyl-ating chemotherapeutic agents, such as procarbazine and/or cyclophosphamide, cause prolonged azoospermia in 90%-100H of men and premature ovarian failure (POP) in 5%-25% of younger women under 30 years old; however, the risks are low with radiotherapy alone if pelvic radiation or chemotherapy with alkylating agents is not given (22).
The purine-like structure of these reductive alkylating agents may permit selective inactivation of purine-utilizing enzymes in low reduction potential tumor cells.
Figure 3: Cancer chemotherapy is evolving toward more selective approaches, with the share of cell messengers expected to increase 2008: $50 billion Non selective cytotoxics anticancers Alkylating agents ~10% Antimetabolities ~9% Antibiotics ~2% Microtubule Inhibitors ~10% Topoisimerase ~3% Hormonal therapies Hormonal therapy ~16% Selective anticancers Cell messengers ~50% 2013: $90 billion Non selective cytotoxics anticancers Alkylating agents ~7% Antimetabolites ~7% Antibiotics ~1% Microtubule Inhibitors ~7% Topoisimerase ~2% Hormonal therapies Hormonal therapy ~11% Selective anticancers Cell messengers ~63% Share of small molecule-based therapies (% of total anticancer sales) ~65% ~55% Note: Table made from pie chart.
3) Molecular genetic evaluation has not proven MLL translocations, which are reported as frequently associated with topoisomerase II inhibitors-induced tAML/MDS (in up to 70% of the cases) or damage to chromosomes 5 and 7, linked to alkylating agents.
Among the chemotherapeutic agents, alkylating agents and topoisomerase II inhibitors have been the most commonly associated with t-MDS/AML.
Some of the clinically-used chemotherapeutic agents, namely bifunctional alkylating agents, act upon the DNA in cancer cells by basically locking the two strands together.
Neither was a history of splenectomy, mediastinal disease, or chemotherapy with alkylating agents.
Cardiovascular events were associated with anthracycline-containing chemotherapy, and alkylating agents appeared to add to that effect.