Tumor immunology top 10 list

The Promise of Preventive Cancer Vaccines

Years of unsuccessful attempts at fighting established tumors with vaccines have taught us all that they are only able to truly impact patient survival when used in a preventive setting, as would normally be the case for traditional vaccines against infectious diseases. While true primary cancer prevention is still but a long-term goal, secondary and tertiary prevention are already in the clinic and providing encouraging results. A combination of immunopreventive cancer strategies and recently approved checkpoint inhibitors is a further promise of forthcoming successful cancer disease control, but prevention will require a considerable reduction of currently reported toxicities. These considerations summed with the increased understanding of tumor antigens allow space for an optimistic view of the future.

MOfinder: a novel algorithm for detecting overlapping modules from protein-protein interaction network

Since organism development and many critical cell biology processes are organized in modular patterns, many algorithms have been proposed to detect modules. In this study, a new method, MOfinder, was developed to detect overlapping modules in a protein-protein interaction (PPI) network. We demonstrate that our method is more accurate than other 5 methods. Then, we applied MOfinder to yeast and human PPI network and explored the overlapping information. Using the overlapping modules of human PPI network, we constructed the module-module communication network. Functional annotation showed that the immune-related and cancer-related proteins were always together and present in the same modules, which offer some clues for immune therapy for cancer. Our study around overlapping modules suggests a new perspective on the analysis of PPI network and improves our understanding of disease.

HER-2/neu as a target for cancer vaccines

A novel modality toward the treatment of HER-2/neu-positive malignancies, mostly including breast and, more recently prostate carcinomas, has been the use of vaccines targeting HER-2/neu extracellular and intracellular domains. HER-2/neu-specific vaccines have been demonstrated to generate durable T-cell anti-HER-2/neu immunity when tested in Phase I and II clinical trials with no significant toxicity or autoimmunity directed against normal tissues. Targeting of HER-2/neu in active immunotherapy may involve peptide and DNA vaccines. Moreover, active anti-HER-2/neu immunization could facilitate the ex vivo expansion of HER-2/neu-specific T cells for use in adoptive immunotherapy for the treatment of established metastatic disease. In addition, early data from trials examining the potential use of HER-2/neu-based vaccines in the adjuvant setting to prevent the relapse of breast cancer in high-risk patients have shown promising results. Future approaches include multiepitope preventive vaccines and combinatorial treatments for generating the most efficient protective anti-tumor immunity.

CIG-DB: the database for human or mouse immunoglobulin and T cell receptor genes available for cancer studies

BACKGROUND

Immunoglobulin (IG or antibody) and the T-cell receptor (TR) are pivotal proteins in the immune system of higher organisms. In cancer immunotherapy, the immune responses mediated by tumor-epitope-binding IG or TR play important roles in anticancer effects. Although there are public databases specific for immunological genes, their contents have not been associated with clinical studies. Therefore, we developed an integrated database of IG/TR data reported in cancer studies (the Cancer-related Immunological Gene Database [CIG-DB]).

DESCRIPTION

This database is designed as a platform to explore public human and murine IG/TR genes sequenced in cancer studies. A total of 38,308 annotation entries for IG/TR proteins were collected from GenBank/DDBJ/EMBL and the Protein Data Bank, and 2,740 non-redundant corresponding MEDLINE references were appended. Next, we filtered the MEDLINE texts by MeSH terms, titles, and abstracts containing keywords related to cancer. After we performed a manual check, we classified the protein entries into two groups: 611 on cancer therapy (Group I) and 1,470 on hematological tumors (Group II). Thus, a total of 2,081 cancer-related IG and TR entries were tabularized. To effectively classify future entries, we developed a computational method based on text mining and canonical discriminant analysis by parsing MeSH/title/abstract words. We performed a leave-one-out cross validation for the method, which showed high accuracy rates: 94.6% for IG references and 94.7% for TR references. We also collected 920 epitope sequences bound with IG/TR. The CIG-DB is equipped with search engines for amino acid sequences and MEDLINE references, sequence analysis tools, and a 3D viewer. This database is accessible without charge or registration at http://www.scchr-cigdb.jp/, and the search results are freely downloadable.

CONCLUSIONS

The CIG-DB serves as a bridge between immunological gene data and cancer studies, presenting annotation on IG, TR, and their epitopes. This database contains IG and TR data classified into two cancer-related groups and is able to automatically classify accumulating entries into these groups. The entries in Group I are particularly crucial for cancer immunotherapy, providing supportive information for genetic engineering of novel antibody medicines, tumor-specific TR, and peptide vaccines.

Harnessing the physiology of lymphopenia to support adoptive immunotherapy in lymphoreplete hosts

Lymphopenia enhances the effectiveness of adoptive immunotherapy by facilitating expansion of transferred T cells but also limits the T-cell repertoire available to mediate immune responses and, in humans, is associated with chronic immune dysfunction. Previous studies concluded that lymphopenia augments adoptive immunotherapy by diminishing Tregs and increasing homeostatic cytokines. We sought to determine whether targeted therapies that replicate the physiology of lymphopenia in lymphoreplete hosts could provide a similarly supportive milieu. Pmel-1 T cells were transferred to B16-bearing lymphopenic versus lymphoreplete mice receiving alphaCD25 and/or recombinant human interleukin-7. Although CD25-based Treg depletion was inefficient because of peripheral expansion of CD4+CD25-FOXP3+ cells, outcomes were better in alphaCD25-treated lymphoreplete hosts than in lymphopenic hosts, and adoptive immunotherapy was most effective in lymphoreplete hosts receiving alphaCD25 plus recombinant human interleukin-7. Lymphopenic hosts supported increased proliferation of adoptively transferred antigen-specific T cells, but cells transferred to lymphoreplete recipients receiving targeted therapies showed superior function. Further, determinant spreading was substantial in lymphoreplete hosts but absent in lymphopenic hosts. These results demonstrate that targeted therapies delivered to mimic the "physiology of lymphopenia" enhance the efficacy of adoptive immunotherapy in lymphoreplete hosts and provide a potentially superior alternative to the induction of lymphopenia.

Combined therapeutic effect of a monoclonal anti-idiotype tumor vaccine against NeuGc-containing gangliosides with chemotherapy in a breast carcinoma model

Anti-idiotypic monoclonal antibodies (mAb) have been evaluated for actively induced immunotherapy with encouraging results. However, rational combination of cancer vaccines with chemotherapy may improve the therapeutic efficacy of these two approaches used separately. The main objective of this study was to evaluate the antitumor effect of the co-administration of 1E10 (Racotumomab), a monoclonal anti-idiotype tumor vaccine against an IgM mAb, named P3 that reacts specifically with NeuGc-containing gangliosides and low-dose Cyclophosphamide in a mammary carcinoma model. F3II tumor-bearing mice were immunized subcutaneously with 100 microg of 1E10 mAb in Alum or with 150 mg/m(2) of Cyclophosphamide intravenously 7 days after the tumor inoculation. While a limited antitumor effect was induced by a single 1E10 mAb immunization; its co-administration with low-dose Cyclophosphamide reduced significantly the F3II mammary carcinoma growth. That response was comparable with the co-administration of the standard high-dose chemotherapy for breast cancer based on 60 mg/m(2) of Doxorubicin and 600 mg/m(2) of Cyclophosphamide, without toxicity signs. Combinatorial chemo-immunotherapy promoted the CD8(+) lymphocytes tumor infiltration and enhanced tumor apoptosis. Furthermore, 1E10 mAb immunization potentiated the antiangiogenic effect of low-dose Cyclophosphamide. Additionally, splenic myeloid cells Gr1(+)/CD11b(+) associated with a suppressor phenotype were significantly reduced in F3II tumor-bearing mice immunized with 1E10 mAb alone or in combination with low-dose Cyclophosphamide. This data may provide a rational for chemo-immunotherapy combinations with potential medical implications in breast cancer.

Chemotherapy induced transient B-cell depletion boosts antibody-forming cells expansion driven by an epidermal growth factor-based cancer vaccine

Cancer vaccines efficacy may improve inducing a rapid and persistent immune response, early at diagnosis along with standard therapies. EGF chemically conjugated to the carrier protein P64k from Neisseria meningitidis in montanide ISA 51 adjuvant is under evaluation, aiming to stimulate a B-cell response. High-dose cyclophosphamide and doxorubicin after priming enhanced the long-term frequency of EGF-specific antibody-forming cells (AFC) of IgM and IgG isotypes, but not the P64k response. Resulting combination, limitedly operational in Btk deficient xid mice, suggests that preferential B-cell lymphocyte space promoted by cyclophosphamide facilitates remaining EGF-specific AFC undergo homeostatic proliferation driven by boosting, amplifying the response.