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 ?
Elias et al., "High-dose combination alkylating agent preparative regimen with autologous bone marrow support: The Dana-Farber Cancer Institute/Beth Israel Hospital experience," Cancer Treatment Reports, vol.
Conditioning regimens determine the overall risk of developing SOS; several alkylating agents given in high doses have been associated with development of SOS in this setting [3, 16].
- 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?
Furthermore, in cases where TEBAC and tetradecyltrimethylammonium bromide acted as alkylating agents, N-substituted compounds were obtained by benzyl and methyl groups, respectively, as can be appreciated.
Recent data indicates that the cancer incidence in patients treated with alkylating agents triples compared to that in the nonexposed population [16].
Alkylating agents, such as cyclophosphamide and chlorambucil, act by suppressing B-cell function, consequently reducing leukocyte count.
Besides corticosteroids, long-term treatment options for the treatment of JIA-associated uveitis include antimetabolites, alkylating agents and biologic agents.
Exposure to multiagent chemotherapy, particularly alkylating agents, may potentiate the effect of previous radiation therapy in childhood and thus serve as another predisposing factor for the development of a postradiation sarcoma [12].
Therapy-related acute leukemias in general have been attributed to topoisomerase II inhibitors and alkylating agents. (1) Patients with therapy-related acute leukemias from alkylating agents generally show a latency of 3-7 years from exposure to the alkylating agent and often have an insidious course, with the development of MDS prior.
The major medications used for chemotherapy include various combinations of the following agents: the immunomodulators thalidomide and lenalidomide; the proteasome inhibitor bortezomib; the alkylating agents melphalan and cyclophosphamide; and the steroids dexamethasone and prednisone.
This is especially true for women who may be receiving gonadotoxic therapies, such as alkylating agents or abdominal/pelvic radiation.