This study investigates the synergistic antitumor efficacy of a triple combination therapy—Nisin (N), Urolithin B (UB), and Vincristine (Vinc)—against human HBK11 lymphoma cells, with an emphasis on proteomic mechanisms of action. The findings elucidate the molecular underpinnings of this novel combination and underscore the potential of postbiotics as adjuvants to conventional chemotherapy, offering a mechanistically informed strategy for improved lymphoma treatment.