The team led by Dr. Liang Tingbo, Chief Physician of Hepatobiliary Pancreatic Surgery at the First Affiliated Hospital of Zhejiang University School of Medicine, in collaboration with a domestic pharmaceutical team, has developed the world's first third-generation oncolytic virus VG161, achieving breakthrough progress in the treatment of recurrent and refractory liver cancer. The relevant results were published in the international academic journal Nature. Oncolytic viruses are a type of natural or recombinant virus that can selectively infect and kill tumor cells without damaging normal cells. The use of oncolytic viruses to treat cancer is a new type of immunotherapy. ”Liang Tingbo said that in recent years, the field of oncolytic virus therapy has shown significant intergenerational evolution characteristics. The first generation oncolytic viruses mainly rely on their own lytic effects, but due to the lack of exogenous gene modifications, the systemic anti-tumor immune response is insufficient. The second-generation oncolytic virus introduces a single immunostimulatory factor to enhance local immune activation, but its overall anti-tumor immunostimulatory ability is relatively weak. In contrast, the third-generation oncolytic virus represented by VG161 innovatively integrates multiple immune co stimulatory factors to achieve multi-target regulation of the anti-tumor immune loop, significantly enhancing systemic anti-tumor effects. Researchers have modified the viral genes, removed the virus's "fangs", and installed the third-generation oncolytic virus VG161 with a "Beidou Navigation" that accurately locates tumor cells. They have also connected some exogenous "assistants" to activate the body's immune system and achieve systemic anti-tumor effects. The development of drug resistance in tumor cells after multi line therapy is a major challenge in the treatment of advanced cancer. Drug resistance not only allows tumor cells to regain growth momentum, but may also lead to further dysfunction of important organs, greatly affecting the survival and quality of life of patients. The research team found that after receiving VG161 treatment, patients continued to use the standard treatment regimen that was already resistant, and the median survival time was further extended from 9.4 months to 20.1 months. This indicates that reversing the immune escape mechanism of tumor cells through oncolytic viruses may also to some extent reverse tumor cell drug resistance, which brings new strategies for the treatment of advanced cancer. In addition, the team has currently developed the world's first fourth generation oncolytic virus VG201. After preliminary verification, the replication ability of VG201 has been enhanced by nearly a hundred times compared to VG161. Even when encountering neutralizing antibodies in peripheral blood, it can efficiently reach tumors and proliferate. Moreover, it can achieve iteration of clinical drug delivery from intratumoral injection to intravenous injection. The relevant research has opened up a new path to overcome tumor cell drug resistance and demonstrated the enormous potential of oncolytic viruses in tumor immunotherapy. ”Liang Tingbo stated that as one of the important directions of tumor immunotherapy, oncolytic viruses have little impact on normal tissues and are still effective for advanced tumors, theoretically preventing cancer recurrence. (New Society)