What is a common method by which targeted therapies deliver their effects?

Targeted therapies are designed to specifically target and interfere with particular molecules or pathways that are crucial for cancer cell growth and survival. The correct choice highlights that these therapies primarily focus on specific proteins involved in cancer processes.

Many cancer treatments, such as monoclonal antibodies or small-molecule inhibitors, are designed to attach to or inhibit the function of specific proteins that may be overexpressed or mutated in cancer cells. For instance, therapies might block receptors on cancer cells or inhibit oncogenic signaling pathways, effectively disrupting the mechanisms that allow cancer cells to proliferate and evade apoptosis. This selective approach minimizes damage to normal cells while maximizing the therapeutic impact on cancer cells.

In contrast, other methods mentioned do not specifically align with the mechanism of targeted therapies. For example, delivering hormones typically pertains to endocrine therapies which are relevant for particular cancers but do not represent the broad spectrum of targeted therapies. Non-specific cytotoxicity refers to traditional chemotherapy, which affects both cancerous and healthy cells indiscriminately, and does not represent the precision of targeted therapy. Lastly, altering metabolic pathways generally is a broader mechanism that does not specifically encapsulate the targeted approach where the focus is on distinct proteins.