Abstract A046: Identification and validation of HCC-specific gene transcriptional signature for tumor antigen discovery

A novel two-step bioinformatics strategy was applied for identification of signatures with therapeutic implications in hepatitis-associated HCC. Transcriptional profiles from HBV- and HCV-associated HCC samples were compared with normal liver tissue controls. Resulting HCC modulated genes were subsequently compared with different normal tissue samples. Two related signatures were identified, namely “HCC-associated” and “HCC-specific.” Expression data were validated by RNA-Seq analysis carried out on unrelated HCC samples and protein expression was confirmed according to the publicly available database at http://www.proteinatlas.org/. Among all, only two proteins (namely AKR1B10 and IGF2BP3) were found strictly HCC-specific with no expression in 18/20 normal tissues. Target peptides for vaccine design were predicted for both proteins associated with the most prevalent HLA-class I and II alleles. The described novel strategy showed to be feasible for identification of HCC-specific proteins as highly potential target for HCC immunotherapy (Petrizzo et al., Scientific Reports, in press).

Citation Format: Annacarmen Petrizzo, Francesca P. Caruso, Maria Tagliamonte, Maria Lina Tornesello, Michele Ceccarelli, Valerio Costa, Marianna Aprile, Roberta Esposito, Gennaro Ciliberto, Franco M. Buonaguro, Luigi Buonaguro. Identification and validation of HCC-specific gene transcriptional signature for tumor antigen discovery [abstract]. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr A046.

Abstract 742: A novel multidrug metronomic chemotherapy significantly delays tumor growth in mice

The tumor immunosuppressive microenvironment represents a major obstacle to an effective tumor-specific cellular immune response.

We have previously shown that a novel multi-drug chemotherapy administered in a metronomic fashion was able to increase immune response to peptides. The chemotherapy consisted of a cocktail including taxanes (paclitaxel and docetaxel) and alkylating (cyclophosphamide) agents. The newly designed strategy was shown to be safe, well tolerated and significantly efficacious (Tagliamonte et al., CII 2015).

In the present study, the effect on the immunosuppressive tumor microenvironment by the same multi-drug cocktail was evaluated in a mouse model upon sub-cutaneous ectopic implantation of B16 melanoma cells.

Treated animals showed a remarkable delay in tumor growth and prolonged survival as compared to control group. Such an effect was directly correlated with CD4+ T cell reduction and CD8+ T cell increase. A significant reduction in the percentage of both CD25+FoxP3+ and CD25+CD127low regulatory T cell population was found in the spleens as well as in the tumor lesions. An intrinsic CD8+ T cell response specific to B16 naturally expressed Trp2 TAA was observed. The same metronomic chemotherapy combined to a vaccine based on mutated antigens, was subsequently shown to increase immune response to vaccine resulting in a significant delay of B16 tumor growth as well as animal survival.

The novel multi-drug daily metronomic chemotherapy evaluated in the present study was very effective in counterbalancing the immunosuppressive tumor microenvironment and enhancing vaccine efficacy. Consequently, the intrinsic as well as vaccine-induced anti-tumor T cell immunity could exert its function containing tumor growth.

Overall, the described metronomic chemotherapy may represent a promising adjuvant approach to enhance anti-tumor cellular immunity and amplify the biological effects of therapeutic cancer vaccines.

Citation Format: Maria Tagliamonte, Annacarmen Petrizzo, Maria Lina Tornesello, Antonio Luciano, Domenica Rea, Antonio Barbieri, Claudio Arra, Maria Napolitano, Gennaro Ciliberto, Franco M. Buonaguro, Luigi Buonaguro. A novel multidrug metronomic chemotherapy significantly delays tumor growth in mice. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 742.

Detection of human papillomavirus DNA in peri-tumor tissues and pelvic lymph nodes as potential molecular marker of micrometastasis in cervical cancer

Background

The association between high risk human papillomaviruses (HPV) and cervical cancer has been firmly established. HPV genome is present in nearly all cases of cervical cancer and detection of viral DNA could therefore be used as a surrogate marker of micrometastasis in peri-tumor tissues and lymph nodes.

Methods

We analyzed primary cervical carcinomas, peri-tumor biopsies and pelvic lymph nodes in 20 women with invasive cancer (FIGO stage I-II) who underwent radical pelvic surgery and lymphadenectomy. HPV DNA was searched by broad spectrum PCR in 142 DNA samples extracted from paraffin embedded tissues. Viral genotypes were identified by direct sequencing analysis.

Results

HPV DNA sequences were identified in all available primary cervical tumors (n = 15). The most common genotype was HPV16 (60 %), followed by HPV18 (20 %), HPV35 (7 %), HPV45 (7 %) and HPV66 (7 %). Seven out of 20 (35 %) women had metastatic spread in peri-tumor tissues and/or lymph nodes, as determined by histology. HPV DNA was detected in all histological positive samples as well as in 16 and 25 % of histological negative peri-tumor tissues and lymph nodes, respectively. Three out of 20 (15 %) women without histological evidence of metastatic spread had HPV-positive lymph nodes. HPV genotype was found always concordant between primary tumor and metastatic lesions. The remaining 10 women (50 %) were histology and HPV-negative in all peri-tumor biopsies and lymph nodes analyzed.

Conclusions

Evaluation of HPV DNA in peri-tumor tissues as well as pelvic lymph nodes could be a sensitive marker to identify micrometastasis or isolated tumor cells and to monitor the risk of disease recurrence in women with cervical cancer.

An overview of new biomolecular pathways in pathogen-related cancers

Cancer molecular pathways are combinations of metabolic processes deregulated in neoplastic cells. Besides pathways specific to tissues from which cancers originate, common neoplastic traits are present among most tumors. Hanahan and Weinberg have described the most critical 'hallmarks' shared by many cancer types. In recent years, cancer stem cell specific properties and pathways have also been identified. Other altered pathways are peculiar of cancer type and cancer stage, even in different cancer stem cell types. In pathogen-related tumors, the alteration of inflammatory and immunologic response along with impairment of cell cycle control represents key molecular events of tumor progression. This article summarizes the recent discoveries of new altered pathways in cancer and their importance in cancer diagnosis and tailored therapies.

Cellular prognostic markers in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the five big killers worldwide and is frequently associated with chronic hepatitis B and C virus (HBV and HCV) infections. Tumor microenvironment consists of a complex network of cells and factors that plays a key role in the tumor progression and prognosis. This is true also for HCC. Several studies have shown strikingly strong correlation between HCC clinical prognosis and intratumoral infiltration of cells affecting tumor growth, invasion, angiogenesis and metastasis. None of such cells is yet validated for routine diagnostic and prognostic assessment. The present review aims at providing a state-of-the-art of such studies.

A novel multi-drug metronomic chemotherapy significantly delays tumor growth in mice

BACKGROUND

The tumor immunosuppressive microenvironment represents a major obstacle to an effective tumor-specific cellular immune response.

METHODS

In the present study, the counterbalance effect of a novel metronomic chemotherapy protocol on such an immunosuppressive microenvironment was evaluated in a mouse model upon sub-cutaneous ectopic implantation of B16 melanoma cells. The chemotherapy consisted of a novel multi-drug cocktail including taxanes and alkylating agents, administered in a daily metronomic fashion. The newly designed strategy was shown to be safe, well tolerated and significantly efficacious.

RESULTS

Treated animals showed a remarkable delay in tumor growth and prolonged survival as compared to control group. Such an effect was directly correlated with CD4(+) T cell reduction and CD8(+) T cell increase. Furthermore, a significant reduction in the percentage of both CD25(+)FoxP3(+) and CD25(+)CD127(low) regulatory T cell population was found both in the spleens and in the tumor lesions. Finally, the metronomic chemotherapy induced an intrinsic CD8(+) T cell response specific to B16 naturally expressed Trp2 TAA.

CONCLUSION

The novel multi-drug daily metronomic chemotherapy evaluated in the present study was very effective in counterbalancing the immunosuppressive tumor microenvironment. Consequently, the intrinsic anti-tumor T cell immunity could exert its function, targeting specific TAA and significantly containing tumor growth. Overall, the results show that this represents a promising adjuvant approach to significantly enhance efficacy of intrinsic or vaccine-elicited tumor-specific cellular immunity.

Combinatorial immunotherapy strategies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common liver malignancy. The prognosis for HCC patients greatly varies according to the stage at diagnosis. Overall it is poor, with a 5-year survival rate of approximately 5-6%. Immunotherapeutic interventions represent a novel and effective therapeutic tool. However, only few immunotherapy trials for HCC have been conducted so far with contrasting results, suggesting that significant improvements are needed. Indeed, the liver is characterized by a strong intrinsic immune suppressive microenvironment which needs to be counterbalanced with immune stimulatory approaches. Therefore, the implementation of combinatorial protocols combining immune stimulatory strategies with specific immunotherapy approaches could result in a dramatic improvement of efficacy and clinical outcome in HCC patients. The present review aims at describing the state of the art in immunotherapy strategies for HCC and future perspectives.

Abstract B130: Evaluation of novel metronomic chemotherapy and cancer vaccine combinatorial strategy

The efficacy of cancer immunotherapy approaches can be significantly hampered by the tumor immune suppressive microenvironment. In the present study, a novel combinatorial strategy (i.e. metronomic chemotherapy plus vaccine) is evaluated in a mouse model in an aggressive therapeutic setting based on sub-cutaneous ectopic implantation of B16 melanoma cells. The chemotherapy is a multi-drug cocktail including taxanes and alkylating agents, administered in a daily metronomic fashion. The vaccine is a multi-peptide cocktail of universal tumor antigen hTERT epitopes adjuvanted in Montanide.

Immunizations have been performed comparing a standard sub-cutaneous delivery with a laser-assisted epidermal immunogen delivery by P.L.E.A.S.E.™ Professional (Pantec Biosolutions). The latter, indeed, creates evenly distributed micropores through to the epidermis and provides a great opportunity to efficiently deliver vaccine antigens to Langerhans cells (LC) in the epidermis.

An interim analysis shows that the immunogenicity as well as the therapeutic effect on tumor growth of the vaccine is significantly increased by the combination with metronomic chemotherapy, and the laser-assisted epidermal immunogen delivery appears to be a very effective strategy as vaccine delivery. Complete description of both immunogenicity and therapeutic effects on tumor growth will be described.

Citation Format: Maria Tagliamonte, Annacarmen Petrizzo, Maria Lina Tornesello, Antonio Luciano, Domenica Rea, Antonio Barbieri, Claudio Arra, Maria Napolitano, Gennaro Ciliberto, Luigi Aurisicchio, Claudio Coscia, Tobias Baechle, Franco M. Buonaguro, Luigi Buonaguro. Evaluation of novel metronomic chemotherapy and cancer vaccine combinatorial strategy. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr B130.

Antigen-specific vaccines for cancer treatment

Vaccines targeting pathogens are generally effective and protective because based on foreign non-self antigens which are extremely potent in eliciting an immune response. On the contrary, efficacy of therapeutic cancer vaccines is still disappointing. One of the major reasons for such poor outcome, among others, is the difficulty of identifying tumor-specific target antigens which should be unique to the tumors or, at least, overexpressed on the tumors as compared to normal cells. Indeed, this is the only option to overcome the peripheral immune tolerance and elicit a non toxic immune response. New and more potent strategies are now available to identify specific tumor-associated antigens for development of cancer vaccine approaches aiming at eliciting targeted anti-tumor cellular responses. In the last years this aspect has been addressed and many therapeutic vaccination strategies based on either whole tumor cells or specific antigens have been and are being currently evaluated in clinical trials. This review summarizes the current state of cancer vaccines, mainly focusing on antigen-specific approaches.

Novel metronomic chemotherapy and cancer vaccine combinatorial strategy for hepatocellular carcinoma in a mouse model

Hepatocellular carcinoma (HCC) is the most frequent primary liver cancer and represents the third and the fifth leading cause of cancer-related death worldwide in men and women, respectively. Hepatitis B virus (HBV) and hepatitis C virus (HCV) chronic infections account for pathogenesis of more than 80 % of primary HCC. HCC prognosis greatly varies according to stage at beginning of treatment, but the overall 5-year survival rate is approximately 5-6 %. Given the limited number of effective therapeutic strategies available, immunotherapies and therapeutic cancer vaccines may help in improving the clinical outcome for HCC patients. However, the few clinical trials conducted to date have shown contrasting results, indicating the need for improvements. In the present study, a novel combinatorial strategy, based on metronomic chemotherapy plus vaccine, is evaluated in a mouse model. The chemotherapy is a multi-drug cocktail including taxanes and alkylating agents, which is administered in a metronomic-like fashion. The vaccine is a multi-peptide cocktail including HCV as well as universal tumor antigen TERT epitopes. The combinatorial strategy designed and evaluated in the present study induces an enhanced specific T cell response, when compared to vaccine alone, which correlates to a reduced Treg frequency. Such results are highly promising and may pave way to relevant improvements in immunotherapeutic strategies for HCC and beyond.

Systems Biology Approach for Cancer Vaccine Development and Evaluation

Therapeutic cancer vaccines do not hold promise yet as an effective anti-cancer treatment. Lack of efficacy or poor clinical outcomes are due to several antigenic and immunological aspects that need to be addressed in order to reverse such trends and significantly improve cancer vaccines’ efficacy. The newly developed high throughput technologies and computational tools are instrumental to this aim allowing the identification of more specific antigens and the comprehensive analysis of the innate and adaptive immunities. Here, we review the potentiality of systems biology in providing novel insights in the mechanisms of the action of vaccines to improve their design and effectiveness.

Update on Head and Neck Cancer: Current Knowledge on Epidemiology, Risk Factors, Molecular Features and Novel Therapies

Tobacco use and alcohol consumption are the main risk factors associated with head and neck squamous cell carcinoma (SCC) development due to their cytotoxic and mutagenic effects on the exposed epithelia of the upper aerodigestive tract. Epstein-Barr virus (EBV) and high-risk human papillomaviruses (HPVs), both encoding viral oncoproteins able to interfere with cell cycle control, have been recognized as the etiological agents of nasopharynx carcinoma and a fraction of oropharyngeal carcinoma, respectively. Head and neck SCC is a deadly disease and despite innovative treatments represents a major challenge for patients. Recently, a number of genomic studies have highlighted the molecular heterogeneity of head and neck SCC based on methylation profiles, microRNA expression, mutated genes and new druggable pathways which may represent new targets for cancer-tailored therapies. To date, cetuximab is the only FDA-approved anti-epidermal growth factor receptor therapy for the treatment of head and neck SCC. In addition, a number of monoclonal antibodies targeting AKT, mTOR and PI3K pathways are under evaluation. Several therapeutic vaccines against HPV16 and EBV proteins are also under study. The purpose of this article is to review the epidemiology, pathogenesis and molecular features of head and neck SCC, with an emphasis on new therapies.

TP53 and PIK3CA gene mutations in adenocarcinoma, squamous cell carcinoma and high-grade intraepithelial neoplasia of the cervix

Background

Mutations in the tumor suppressor gene TP53 and proto-oncogene PIK3CA and alterations of p53 and PIK3CA AKT mTOR pathways are common events in several human cancers. We focused on the analysis of TP53 and PIK3CA gene variations in adenocarcinoma, squamous cell carcinoma as well as in intraepithelial neoplasia grade 3 of the cervix.

Methods

DNA samples from 28 cervical adenocarcinoma, 55 squamous cell carcinoma and 31 intraepithelial neoplasia grade 3 (CIN3), previously characterized in terms of human papillomavirus (HPV) prevalence and genotype distribution, were analyzed for TP53 and PIK3CA mutations in the exons 4–9 and exon 9, respectively.

Results

Single nucleotide substitutions in TP53 and PIK3CA genes were detected in 36% and 11% of adenocarcinoma, in 16% and in 5% of squamous cell carcinoma, and in 13% and none of CIN 3, respectively. Nucleotide changes in TP53 were significantly more frequent in adenocarcinoma cases than in squamous cell carcinoma and CIN3 (P = 0.035) and were independent from HPV infection status.

Conclusions

Mutations in the TP53 gene and to lesser extent in the PIK3CA gene seem more frequent in cervical adenocarcinoma than in squamous cell carcinoma and CIN3. Whether TP53 and PIK3CA gene mutations have an impact on prognosis and response to molecularly targeted therapies as well as in cytotoxic drugs in different cervical cancer histotypes needs to be analyzed in investigative clinical trials.

Burkitt lymphoma research in East Africa: highlights from the 9(th) African organization for research and training in cancer conference held in Durban, South Africa in 2013

A one-day workshop on Burkitt lymphoma (BL) was held at the 9(th) African Organization for Research and Training in Cancer (AORTIC) conference in 2013 in Durban, South Africa. The workshop featured 15 plenary talks by delegates representing 13 institutions that either fund or implement research on BL targeting AORTIC delegates primarily interested in pediatric oncology. The main outcomes of the meeting were improved sharing of knowledge and experience about ongoing epidemiologic BL research, BL treatment in different settings, the role of cancer registries in cancer research, and opportunities for African scientists to publish in scientific journals. The idea of forming a consortium of BL to improve coordination, information sharing, accelerate discovery, dissemination, and translation of knowledge and to build capacity, while reducing redundant efforts was discussed. Here, we summarize the presentations and discussions from the workshop.

Formation of self-assembled triple-layered rotavirus-like particles (tlRLPs) by constitutive co-expression of VP2, VP6, and VP7 in stably transfected high-five insect cell lines

In this study, stable high-five insect cell line constitutively expressing rotavirus (RV) VP2 was co-transfected with VP6 and VP7-recombinant plasmids. The presence of RV proteins in stably transfected high-five cells was verified by molecular and protein analyses. To yield self-assembled triple-layered RV-like particles (tlRLPs), a stable insect high-five cell line was generated to produce RV VP6 and VP7 besides VP2. Self-assembled tlRLPs were observed by transmission electron microscopy (TEM), and enzyme-linked immunosorbent assay (ELISA) was used to assess their antigenicity in vivo. The results suggest that the stable transfected high-five cells are able to generate tlRLPs with the efficient antigenicity.

Systems vaccinology for cancer vaccine development

Results of therapeutic vaccines for established chronic infections or cancers are still unsatisfactory. The only therapeutic cancer vaccine approved for clinical use is the sipuleucel-T, for the treatment of metastatic prostate cancer, which induces a limited 4-month improvement in the overall survival of vaccinated patients compared to controls. This represents a remarkable advancement in the cancer immunotherapy field, although the clinical outcome of cancer vaccines needs to be substantially improved. To this aim, a multipronged strategy is required, including the evaluation of mechanisms underlying the effective elicitation of immune responses by cancer vaccines. The recent development of new technologies and computational tools allows the comprehensive and quantitative analysis of the interactions between all of the components of innate and adaptive immunity over time. Here we review the potentiality of systems biology in providing novel insights in the mechanisms of action of vaccines to improve their design and effectiveness.

Infectious Agents and Cancer reviewer acknowledgement 2013

Contributing reviewers

Prediction of individual immune responsiveness to a candidate vaccine by a systems vaccinology approach

Background

We have previously shown that a candidate idiotype vaccine, based on the IGKV3-20 light chain protein, is able to induce activation of circulating antigen presenting cells (APCs) in both HCV-positive and HCV-negative subjects, with production of Th2-type cytokines. In addition, such a candidate idiotype vaccine induces an early gene expression pattern, characterized by the strong induction of an innate immune response, and a late pattern, characterized by a prevalent B cell response. Nonetheless, some HCV-positive individuals showed a complete lack of maturation of circulating APCs with low levels of cytokine production, strongly suggesting the possible identification of selective impairments in immune response in individual subjects.

Method

Peripheral blood mononuclear cells (PBMCs) were stimulated ex vivo with IGKV3-20 for 24 h and 6 days. Analysis of the global gene expression profile as well as the cytokine pattern was performed for individual subjects.

Results

The gene expression profile showed a strong agreement with the cytokine pattern. Indeed, the expression pattern of immune-related genes is highly predictive of the individual immunological phenotype.

Conclusion

The overall results represent a proof of concept, indicating the efficacy of such an ex vivo screening platform for predicting individual’s responsiveness to an antigen as well as guiding optimization of vaccine design. Larger cohort study will be needed to validate results observed in the study.