Cancer is a major and serious problem for human health. Despite the many advances in the field of treatment, it remains the biggest global medical challenge. The main barrier to treating this disease is a process called metastasis, which occurs in 90% of cancers.
According to World Health Statistics, breast cancer is among the three world's prevalent cancers and the second largest cause of cancer deaths in the world that is about 1.67 million people. Bone, liver, lung and brain are common organs for metastatic breast cancer. Proprietary processes and various molecules play a role in metastasis to each of these organs. The target microorganisms first cause the cancer cells to be present in these organs, and then the release of specific factors from cancer cells and their interaction with the target micro-environment results in the survival of these cells and the formation of metastasis. In this review article, we try to find out the key molecules of these mechanisms that can be considered as an appropriate therapeutic target for breast cancer by studying the mechanisms involved in metastatic breast cancer to target organs.