Recent breakthroughs shed light on metabolic and immune pathways in cancer. Targeting spermine metabolism enhances pancreatic cancer immunity, potentially improving immunotherapies. Meanwhile, anti-PD-1 therapies show improved efficacy in gastric cancer patients with chronic hepatitis B, revealing viral infection influence on cancer treatment success. Additionally, the enzyme B3GNT5 regulates EMT, MET, and chemoresistance mechanisms in tumors, highlighting a novel target for overcoming drug resistance in oncology.