Cancer is increasingly recognized as a complex disease influenced not only by genetic mutations but also by the tumor microenvironment (TME). This review highlights how the TME plays a critical role in cancer progression, with non-genetic factors such as epigenetic changes, physical forces, and interactions between cells and their environment driving malignant transformation. The TME includes immune cells, cancer-associated fibroblasts (CAFs), blood vessels, and the extracellular matrix (ECM), all of which can influence tumor behavior. For example, oncogenic mutations in a single cell can lead to malignancy through interactions with the TME, which can alter downstream signaling and promote tumor growth. The TME also affects the behavior of cancer stem cells (CSCs), which are crucial for tumor initiation and progression. Inflammation, mechanical forces, and metabolic changes in the TME can all contribute to cancer development and progression. Additionally, the TME can influence the response to therapy, with factors such as diet, stress, and hormonal changes affecting tumor outcomes. The review emphasizes the importance of understanding the TME in cancer therapy, as it can provide new targets for treatment. Non-genetic factors, including epigenetic modifications and changes in the TME, can also drive cancer progression, highlighting the need for a more comprehensive approach to cancer research and treatment. The study of the TME is crucial for developing new therapies that target the environment in which cancer cells grow.Cancer is increasingly recognized as a complex disease influenced not only by genetic mutations but also by the tumor microenvironment (TME). This review highlights how the TME plays a critical role in cancer progression, with non-genetic factors such as epigenetic changes, physical forces, and interactions between cells and their environment driving malignant transformation. The TME includes immune cells, cancer-associated fibroblasts (CAFs), blood vessels, and the extracellular matrix (ECM), all of which can influence tumor behavior. For example, oncogenic mutations in a single cell can lead to malignancy through interactions with the TME, which can alter downstream signaling and promote tumor growth. The TME also affects the behavior of cancer stem cells (CSCs), which are crucial for tumor initiation and progression. Inflammation, mechanical forces, and metabolic changes in the TME can all contribute to cancer development and progression. Additionally, the TME can influence the response to therapy, with factors such as diet, stress, and hormonal changes affecting tumor outcomes. The review emphasizes the importance of understanding the TME in cancer therapy, as it can provide new targets for treatment. Non-genetic factors, including epigenetic modifications and changes in the TME, can also drive cancer progression, highlighting the need for a more comprehensive approach to cancer research and treatment. The study of the TME is crucial for developing new therapies that target the environment in which cancer cells grow.