TSC2 and subependymal giant cell astrocytoma: TSC1 or TSC2 mutations cause excessive activation of mTOR pathway, leading to the promotion of cell growth and proliferation that caused a wide variety of tumor cell growth in TSC, including renal angiomyolipoma (RAML), pulmonary lymphangioleiomyomatosis (PLAM), subependymal giant cell astrocytoma (SEGA) and facial angiofibroma (8).