The present invention discloses that cancer cells secrete succinate into extracellular milieu, which increases macrophage migration and mediates TAM polarization. Furthermore, succinate induces cancer cell EMT, enhances cancer cell migration, and promotes cancer metastasis in murine models. It is indicated in the present invention that serum succinate concentration is elevated in patients with lung cancer when compared to healthy subjects. It implies that during cancer development and progression, cancer cells release a large quantity of succinate into the circulation. As shown in the present invention, serum succinate has a high discriminatory power, it represents a new class of circulating oncometabolite with potential value for predicting NSCLC. Furthermore, as elevation of succinate level in LLC tumor model is accompanied by increased TAMs in the subcutaneous tumors and enhanced cancer metastasis, serum succinate may be a useful therapeutic biomarker for NSCLC treatment. The present invention also provides an anti-succinate antibody that can serve as a cancer therapeutic agent.
