Role of lymphocytes, macrophages and immune receptors in suppression of tumor immunity

Immunotherapy Vaccines for Prostate Cancer Treatment

BACKGROUND

Therapeutic tumor vaccines have emerged as a compelling avenue for treating patients afflicted with advanced prostate cancer (PCa), particularly those experiencing biochemical relapse or ineligible for surgical intervention. This study serves to consolidate recent research findings on therapeutic vaccines targeting prostate tumors while delineating prevalent challenges within vaccine research and development.

METHODS

We searched electronic databases, including PubMed, Web of Science, Embase, and Scopus, up to August 31, 2024, using keywords such as 'vaccine', 'prostate cancer', 'immunotherapy', and others. We reviewed studies on various therapeutic vaccines, including dendritic cell-based, antigen, nucleic acid, and tumor cell vaccines.

RESULTS

Studies consistently showed that therapeutic vaccines, notably DC vaccines, had favorable safety profiles with few adverse effects. These vaccines, with varied antigenic formulations, demonstrated strong clinical outcomes, as indicated by metrics such as PSA response rates (9.5%-58%), extended PSA doubling times (52.9%-89.7%), overall survival durations (17.7-33.8 months), two-year mortality rates (0%-12.5%), biochemical relapse rates (42%-73%), and antigen-specific immune responses (33.3%-71.4% in responsive groups).

CONCLUSION

While clinical data for tumor vaccines have illuminated robust evidence of tumoricidal activity, the processes of their formulation and deployment are riddled with complexities. Combining vaccines with other therapies may enhance outcomes, and future research should focus on early interventions and deciphering the immune system's role in oncogenesis.

Bladder Cancer: Immunotherapy and Pelvic Lymph Node Dissection

Bladder cancer, a common malignancy of the urinary system, is routinely treated with radiation, chemotherapy, and surgical excision. However, these strategies have inherent limitations and may also result in various side effects. Immunotherapy has garnered considerable attention in recent years as a novel therapeutic approach. It harnesses and activates the patient's immune system to recognize and eliminate cancer cells, which not only prolongs therapeutic efficacy but also minimizes the toxic side effects. Several immune checkpoint inhibitors and cancer vaccines have been developed for the treatment of bladder cancer. Whereas blocking immune checkpoints on the surface of tumor cells augments the effect of immune cells, immunization with tumor-specific antigens can elicit the production of anti-tumor immune effector cells. However, there are several challenges in applying immunotherapy against bladder cancer. For instance, the efficacy of immunotherapy varies considerably across individual patients, and only a small percentage of cancer patients are responsive. Therefore, it is crucial to identify biomarkers that can predict the efficacy of immunotherapy. Pelvic lymph nodes are routinely dissected from bladder cancer patients during surgical intervention in order to remove any metastatic tumor cells. However, some studies indicate that pelvic lymph node dissection may reduce the efficacy of immunotherapy by damaging the immune cells. Therefore, the decision to undertake pelvic lymph node removal should be incumbent on the clinical characteristics of individual patients. Thus, although immunotherapy has the advantages of lower toxic side effects and long-lasting efficacy, its application in bladder cancer still faces challenges, such as the lack of predictive biomarkers and the effects of pelvic lymph node dissection. Further research is needed to explore these issues in order to improve the efficacy of immunotherapy for bladder cancer.

Cancer Vaccines in the Immunotherapy Era: Promise and Potential

Therapeutic vaccines are a promising alternative for active immunotherapy for different types of cancers. Therapeutic cancer vaccines aim to prevent immune system responses that are not targeted at the tumors only, but also boost the anti-tumor immunity and promote regression or eradication of the malignancy without, or with minimal, adverse events. Clinical trial data have pushed the development of cancer vaccines forward, and the US Food and Drug Administration authorized the first therapeutic cancer vaccine. In the present review, we discuss the various types of cancer vaccines and different approaches for the development of therapeutic cancer vaccines, along with the current state of knowledge and future prospects. We also discuss how tumor-induced immune suppression limits the effectiveness of therapeutic vaccinations, and strategies to overcome this barrier to design efficacious, long-lasting anti-tumor immune responses in the generation of vaccines.