Immune modulation as a therapeutic strategy for non-small-cell lung cancer

Differentiated regulation of immune-response related genes between LUAD and LUSC subtypes of lung cancers

Lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) are the two major subtypes of lung cancer, with LUSC exhibits faster progression rate than LUAD. To investigate the roles of immune-response related genes (IRGs) in lung cancer progression, we used LUAD and LUSC samples at different cancer progression stages, and identified that the expression profiles of IRGs could serve as a better classification marker for cancerous tissues of both LUAD and LUSC. We found that the expression changes of IRGs were different between LUAD and LUSC. Cell cycle promoting genes, including KIFs and proteasomes, showed faster up-regulation in LUSC, whereas immune response promoting genes, including MHC molecules and chemokines, were more rapidly repressed in LUSC. Comparative pathway analysis revealed that members of the Toll-like receptor and T cell receptor signaling pathways exhibited diverged expression changes between LUAD and LUSC, especially at the early cancer stages. Our results revealed the difference of LUAD and LUSC from the immune response point of view, and provided new clues for the differential treatment of LUAD and LUSC.

Immunotherapy as a strategy for the treatment of non-small-cell lung cancer

Positive modulation of a patient's immune system to produce antitumor immunity is an attractive strategy that may improve the dismal outcomes typically associated with non-small-cell lung cancer (NSCLC). Using methods that either augment specific antitumor immunity or positively influence the patient's immune system to allow the de novo generation of immunity to encompass current strategies used in recent clinical trials of NSCLC. Encouraging results of Phase II trials in antigen-specific immunotherapy have led to three subsequent Phase III trials, which are currently enrolling. Results of these trials will improve our understanding of the role that immunotherapy plays in the treatment of NSCLC. Successful application of a humoral vaccine in Cuba led to its approval for the treatment of advanced NSCLC patients in that country. To date, trials involving nonspecific immunotherapeutic interventions have failed to improve outcomes in NSCLC and may indicate a need to combine them with antigen-specific vaccines. Although these trials will greatly advance our knowledge of NSCLC immunotherapy, we believe truly efficacious immunotherapy may only result from implementation of strategies to both augment antitumor immunity and counteract tumor-mediated immunosuppression.

The anti-tumor effect of Newcastle disease virus HN protein is influenced by differential subcellular targeting

BACKGROUND

Immunotherapy is emerging as a major player in the current standard of care for aggressive cancers such as non-small cell lung cancer (NSCLC). The Newcastle disease virus with its tumor-specific replicative and oncolytic abilities is a promising immunotherapeutic candidate. A DNA vaccine expressing the major immunogenic hemagglutinin-neuraminidase (HN) protein of this virus has shown promising results as an immunotherapeutic agent.

METHODS

In the present study, three different DNA vaccine constructs encoding differentially targeted HN proteins (cytoplasmic or Cy-HN, secreted or Sc-HN and membrane-anchored or M-HN) were generated to evaluate their anti-tumor effect in vitro and in vivo.

RESULTS

Although all three DNA constructs elicited an immune response, tumor-bearing mice intratumorally injected with M-HN demonstrated a significantly better anti-tumor effect than those injected with Cy-HN or Sc-HN. We also showed that this anti-tumor effect was mediated by higher lymphocyte proliferative response and CTL activity in mice intratumorally injected with M-HN.

CONCLUSION

The membrane-anchored form of the HN protein appears to be an ideal candidate to develop as an immunotherapeutic agent for NSCLC.

Antitumoral efficacy of DNA nanoparticles in murine models of lung cancer and pulmonary metastasis

Polyethylenimine (PEI)-DNA complexes are nanoparticles that are able to efficiently transfer plasmids to the lungs. Interleukin-12 (IL12) gene transfer using PEI may represent an important strategy for lung cancer treatment. In this study, we evaluated the antitumoral efficacy of the administration of PEI-DNA nanoparticles carrying IL12 gene (PEI-IL12) for the treatment of lung cancer and pulmonary metastases in animal models. After inoculation of tumor cells, mice were treated intravenously with a single dose of PEI-IL12, PEI nanoparticles carrying the reporter gene beta-galactosidase (PEI-LacZ) or vehicle. Transgene expression, survival rates and immune response were analyzed in both models. Administration of PEI-LacZ and PEI-IL12 nanoparticles controlled tumor growth and prolonged survival times in both animal models. Although PEI-IL12 and PEI-LacZ administration showed similar antitumoral effects in the lung cancer model, the efficacy of PEI-IL12 was significantly superior in the inhibition of the development of pulmonary metastases. Furthermore, the administration of PEI-DNA nanoparticles results in the production of high levels of proinflammatory cytokines. Our results showed that PEI-DNA nanoparticles are an efficient vector for mediating gene transfer to the lungs, are a potent inducer of the innate immune response and represents an interesting strategy for the treatment of bronchogenic carcinoma and metastatic lung carcinoma.

Comparison on in vitro characterization of fucospheres and chitosan microspheres encapsulated plasmid DNA (pGM-CSF): formulation design and release characteristics

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine used in the treatment of serious conditions resulting from chemotherapy and bone marrow transplantation such as neutropenia and aplastic anemia. Despite these effects, GM-CSF has a very short biological half-life, and it requires frequent injection during the treatment. Therefore, the cytokine production is possible in the body with plasmid-encoded GM-CSF (pGM-CSF) coding for cytokine administered to the body. However, the selection of the proper delivery system for the plasmid is important. In this study, two different delivery systems, encapsulated plasmid such as fucoidan-chitosan (fucosphere) and chitosan microspheres, were prepared and the particle physicochemical properties evaluated. Fucospheres and chitosan microspheres size ranges are 151-401 and 376-681 nm. The zeta potential values of the microspheres were changed between 8.3-17.1 mV (fucosphere) and +21.9-28.9 mV (chitosan microspheres). The encapsulation capacity of fucospheres changed between 84.2% and 94.7% depending on the chitosan molecular weight used in the formulation. In vitro plasmid DNA release from both delivery systems exhibited slower profiles of approximately 90-140 days. Integrity of released samples was checked by agarose gel electrophoresis, and any additional band was not seen. All formulations were analyzed kinetically. The calculated regression coefficients showed a higher r2 value with zero-order kinetics. In conclusion, the characterizations of the microspheres can be modulated by changing the formulation variables, and it can be concluded that fucospheres might be a potential carrier system for the controlled delivery of GM-CSF encoding plasmid DNA.