Repurposing Infectious Diseases Vaccines Against Cancer

Vaccines used to prevent infections have long been known to stimulate immune responses to cancer as illustrated by the approval of the Bacillus Calmette-Guérin (BCG) vaccine to treat bladder cancer since the 1970s. The recent approval of immunotherapies has rejuvenated this research area with reports of anti-tumor responses with existing infectious diseases vaccines used as such, either alone or in combination with immune checkpoint inhibitors. Here, we have reviewed and summarized research activities using approved vaccines to treat cancer. Data supporting a cancer therapeutic use was found for 16 vaccines. For 10 (BCG, diphtheria, tetanus, human papillomavirus, influenza, measles, pneumococcus, smallpox, typhoid and varicella-zoster), clinical trials have been conducted or are ongoing. Within the remaining 6, preclinical evidence supports further evaluation of the rotavirus, yellow fever and pertussis vaccine in carefully designed clinical trials. The mechanistic evidence for the cholera vaccine, combined with the observational data in colorectal cancer, is also supportive of clinical translation. There is limited data for the hepatitis B and mumps vaccine (without measles vaccine). Four findings are worth highlighting: the superiority of intravesical typhoid vaccine instillations over BCG in a preclinical bladder cancer model, which is now the subject of a phase I trial; the perioperative use of the influenza vaccine to limit and prevent the natural killer cell dysfunction induced by cancer surgery; objective responses following intratumoral injections of measles vaccine in cutaneous T-cell lymphoma; objective responses induced by human papillomavirus vaccine in cutaneous squamous cell carcinoma. All vaccines are intended to induce or improve an anti-tumor (immune) response. In addition to the biological and immunological mechanisms that vary between vaccines, the mode of administration and sequence with other (immuno-)therapies warrant more attention in future research.

Association between liver targeted antiviral therapy in colorectal cancer and survival benefits: An appraisal

In colorectal cancer (CRC), liver metastasis remains a major contributor to the cause of cancer-related death. Putative biomarkers, therapeutic efficacy, and drug insensitivity still pose clinical challenges for metastatic CRC patients. Interestingly, previous studies indicated that tumor cells in CRC did not metastasize to the injured liver, which included hepatitis or cirrhotic liver. The benefits of antiviral therapy on hepatocellular carcinoma have also been identified. This review discusses the role of antiviral therapy on the liver. Antiviral therapy may reduce potential liver metastasis associated with CRC in several mechanistic aspects.

Hypothesis: Could Hepatitis B vaccine act as an immune adjuvant in glioblastoma? Clues to conduct further epidemiological analyses

A failure of neurodevelopmental differentiation at the level of oligodendroglial-astrocytic biprogenitors (O2A) is shown to be involved in the pathogenesis of both multiple sclerosis (MS) and glioblastoma multiforme (GBM). In this review article, we suggest that certain antigens of Hepatitis B Virus (HBV) and HBV-Vaccine (HBV-V) could act as immune stimulants in GBM treatment based on several lines of evidence. HBV-Vs may cause rare but prominent neuroimmune side effects including demyelination and multiple sclerosis, which may be associated with HBV-proteins creating antigenic mimicry of oligodendroglial progenitors. The combined prevalance of HBV and Hepatitis C Virus-carrier state is less in patients with brain tumors compared to healthy subjects. Furthermore, within the population of patients with brain tumors, the prevalence is even about two times lesser in GBM in comparison to those with a diagnosis of meningioma. Although indirectly, this epidemiological data may indicate that the immune response triggered against hepadnavirus antigens would eliminate aberrantly differentiating O2A progenitor cells giving rise to GBMs. Moreover, Hepatitis B surface antigen-antibody variable domain is among the top 100 differentially expressed transcripts in fresh frozen and formalin-fixed paraffin-embeded specimens obtained from pediatric GBM tissues in comparison to the control brain tissues. However, the provided evidence is still premature and we think that HBV-V warrants investigation first by epidemiological studies and then by animal experiments to determine whether it reduces the risk of GBM and whether it could slow GBM growth via immune stimulation.