What are the two major classifications of antitumor antibiotics?

The correct answer identifies the two major classifications of antitumor antibiotics as anthracyclines and non-anthracyclines.

Anthracyclines are a class of drugs that are derived from the bacterium Streptomyces. They are well-known for their effectiveness in treating various types of cancer, particularly hematologic malignancies and solid tumors. Common examples include doxorubicin, daunorubicin, and epirubicin. These agents work by intercalating into DNA, thereby inhibiting nucleic acid synthesis and triggering mechanisms that lead to cell death.

Non-anthracyclines encompass a range of other antitumor antibiotics that also exhibit cytotoxic properties but do not belong to the anthracycline family. Examples include dactinomycin and mitomycin. These drugs act through different mechanisms than anthracyclines, with some working by causing DNA damage through different pathways.

The classifications in the other options do not accurately reflect the specific category of antitumor antibiotics. Monoclonal antibodies and small molecules refer to targeted therapies, cytotoxic and targeted agents cover a broader range of cancer treatment modalities but do not classify specifically as antitumor antibiotics, and hormonal agents and immunotherapy represent