Several factors can contribute to tumor promotion. These include chronic inflammation, hormonal imbalances, and exposure to certain chemicals. For instance, inflammatory cytokines and growth factors can create a microenvironment that supports the survival and proliferation of cancer cells. Hormones like estrogen have been implicated in promoting breast cancer. Additionally, certain chemicals known as tumor promoters, such as phorbol esters, can activate signaling pathways that lead to cell proliferation without causing DNA damage.
