Induction of Immune-Stimulating Factors and Oncolysis Upon p14ARF Gene Transfer in Melanoma Cell Lines.

Together with an anti-tumor immune response, oncolysis using a recombinant viral vector promises to eliminate cancer cells by both gene transfer and host-mediated functions. In this study we explore oncolysis induced by nonreplicating adenoviral vectors used for p14ARF and interferon-ß (hIFNß) gene transfer in human melanoma cell lines, revealing an unexpected role for p14ARF in promoting cellular responses predictive of immune stimulation. Oncolysis was confirmed when UACC-62 (p53 wild-type) cells succumbed upon p14ARF gene transfer in vitro, whereas SK-Mel-29 (p53-mutant) benefitted from its combination with hIFNß. In the case of UACC-62, in situ gene therapy in nude mice yielded reduced tumor progression in response to the p14ARF and hIFNß combination. Potential for immune stimulation was revealed where p14ARF gene transfer in vitro was sufficient to induce emission of immunogenic cell death factors in UACC-62 and upregulate pro-immune genes, including IRF1, IRF7, IRF9, ISG15, TAP-1, and B2M. In SK-Mel-29, p14ARF gene transfer induced a subset of these factors. hIFNß was, as expected, sufficient to induce these immune-stimulating genes in both cell lines. This work is a significant advancement for our melanoma gene therapy strategy because we revealed not only the induction of oncolysis, but also the potential contribution of p14ARF to immune stimulation.

Exploration of p53 plus interferon-beta gene transfer for the sensitization of human colorectal cancer cell lines to cell death.

While treatments for colorectal cancer continue to improve, some 50% of patients succumb within 5 years, pointing to the need for additional therapeutic options. We have developed a modified non-replicating adenoviral vector for gene transfer, called AdRGD-PG, which offers improved levels of transduction and transgene expression. Here, we employ the p53-responsive PG promoter to drive expression of p53 or human interferon-ß (hIFNß) in human colorectal cancer cell lines HCT116wt (wtp53), HCT116-/- (p53 deficient) and HT29 (mutant p53). The HCT116 cell lines were both easily killed with p53 gene transfer, while combined p53 and hIFNß cooperated for the induction of HT29 cell death and emission of immunogenic cell death (ICD) markers. Elevated annexinV staining and caspase 3/7 activity point to cell death by a mechanism consistent with apoptosis. P53 gene transfer alone or in combination with hIFNß sensitized all cell lines to chemotherapy, permitting the application of low drug doses while still achieving significant loss of viability. While endogenous p53 status was not sufficient to predict response to treatment, combined p53 and hIFNß provided an additive effect in HT29 cells. We propose that this approach may prove effective for the treatment of colorectal cancer, permitting the use of limited drug doses.

Perspectives for cancer immunotherapy mediated by p19Arf plus interferon-beta gene transfer.

While cancer immunotherapy has gained much deserved attention in recent years, many areas regarding the optimization of such modalities remain unexplored, including the development of novel approaches and the strategic combination of therapies that target multiple aspects of the cancer-immunity cycle. Our own work involves the use of gene transfer technology to promote cell death and immune stimulation. Such immunogenic cell death, mediated by the combined transfer of the alternate reading frame (p14ARF in humans and p19Arf in mice) and the interferon-ß cDNA in our case, was shown to promote an antitumor immune response in mouse models of melanoma and lung carcinoma. With these encouraging results, we are now setting out on the road toward translational and preclinical development of our novel immunotherapeutic approach. Here, we outline the perspectives and challenges that we face, including the use of human tumor and immune cells to verify the response seen in mouse models and the incorporation of clinically relevant models, such as patient-derived xenografts and spontaneous tumors in animals. In addition, we seek to combine our immunotherapeutic approach with other treatments, such as chemotherapy or checkpoint blockade, with the goal of reducing dosage and increasing efficacy. The success of any translational research requires the cooperation of a multidisciplinary team of professionals involved in laboratory and clinical research, a relationship that is fostered at the Cancer Institute of Sao Paulo.

Perspectives for cancer immunotherapy mediated by p19Arf plus interferon-beta gene transfer

While cancer immunotherapy has gained much deserved attention in recent years, many areas regarding the optimization of such modalities remain unexplored, including the development of novel approaches and the strategic combination of therapies that target multiple aspects of the cancer-immunity cycle. Our own work involves the use of gene transfer technology to promote cell death and immune stimulation. Such immunogenic cell death, mediated by the combined transfer of the alternate reading frame (p14ARF in humans and p19Arf in mice) and the interferon-β cDNA in our case, was shown to promote an antitumor immune response in mouse models of melanoma and lung carcinoma. With these encouraging results, we are now setting out on the road toward translational and preclinical development of our novel immunotherapeutic approach. Here, we outline the perspectives and challenges that we face, including the use of human tumor and immune cells to verify the response seen in mouse models and the incorporation of clinically relevant models, such as patient-derived xenografts and spontaneous tumors in animals. In addition, we seek to combine our immunotherapeutic approach with other treatments, such as chemotherapy or checkpoint blockade, with the goal of reducing dosage and increasing efficacy. The success of any translational research requires the cooperation of a multidisciplinary team of professionals involved in laboratory and clinical research, a relationship that is fostered at the Cancer Institute of Sao Paulo.

Transcriptional profile of fibroblasts obtained from the primary site, lymph node and bone marrow of breast cancer patients.

Cancer-associated fibroblasts (CAF) influence tumor development at primary as well as in metastatic sites, but there have been no direct comparisons of the transcriptional profiles of stromal cells from different tumor sites. In this study, we used customized cDNA microarrays to compare the gene expression profile of stromal cells from primary tumor (CAF, n = 4), lymph node metastasis (N+, n = 3) and bone marrow (BM, n = 4) obtained from breast cancer patients. Biological validation was done in another 16 samples by RT-qPCR. Differences between CAF vs N+, CAF vs BM and N+ vs BM were represented by 20, 235 and 245 genes, respectively (SAM test, FDR < 0.01). Functional analysis revealed that genes related to development and morphogenesis were overrepresented. In a biological validation set, NOTCH2 was confirmed to be more expressed in N+ (vs CAF) and ADCY2, HECTD1, HNMT, LOX, MACF1, SLC1A3 and USP16 more expressed in BM (vs CAF). Only small differences were observed in the transcriptional profiles of fibroblasts from the primary tumor and lymph node of breast cancer patients, whereas greater differences were observed between bone marrow stromal cells and the other two sites. These differences may reflect the activities of distinct differentiation programs.

Transcriptional effects of 1,25 dihydroxyvitamin D(3) physiological and supra-physiological concentrations in breast cancer organotypic culture.

BACKGROUND: Vitamin D transcriptional effects were linked to tumor growth control, however, the hormone targets were determined in cell cultures exposed to supra physiological concentrations of 1,25(OH)(2)D(3) (50-100nM). Our aim was to evaluate the transcriptional effects of 1,25(OH)(2)D(3) in a more physiological model of breast cancer, consisting of fresh tumor slices exposed to 1,25(OH)(2)D(3) at concentrations that can be attained in vivo. METHODS: Tumor samples from post-menopausal breast cancer patients were sliced and cultured for 24 hours with or without 1,25(OH)(2)D(3) 0.5nM or 100nM. Gene expression was analyzed by microarray (SAM paired analysis, FDR≤0.1) or RT-qPCR (p≤0.05, Friedman/Wilcoxon test). Expression of candidate genes was then evaluated in mammary epithelial/breast cancer lineages and cancer associated fibroblasts (CAFs), exposed or not to 1,25(OH)(2)D(3) 0.5nM, using RT-qPCR, western blot or immunocytochemistry. RESULTS: 1,25(OH)(2)D(3) 0.5nM or 100nM effects were evaluated in five tumor samples by microarray and seven and 136 genes, respectively, were up-regulated. There was an enrichment of genes containing transcription factor binding sites for the vitamin D receptor (VDR) in samples exposed to 1,25(OH)(2)D(3) near physiological concentration. Genes up-modulated by both 1,25(OH)(2)D(3) concentrations were CYP24A1, DPP4, CA2, EFTUD1, TKTL1, KCNK3. Expression of candidate genes was subsequently evaluated in another 16 samples by RT-qPCR and up-regulation of CYP24A1, DPP4 and CA2 by 1,25(OH)(2)D(3) was confirmed. To evaluate whether the transcripitonal targets of 1,25(OH)(2)D(3) 0.5nM were restricted to the epithelial or stromal compartments, gene expression was examined in HB4A, C5.4, SKBR3, MDA-MB231, MCF-7 lineages and CAFs, using RT-qPCR. In epithelial cells, there was a clear induction of CYP24A1, CA2, CD14 and IL1RL1. In fibroblasts, in addition to CYP24A1 induction, there was a trend towards up-regulation of CA2, IL1RL1, and DPP4. A higher protein expression of CD14 in epithelial cells and CA2 and DPP4 in CAFs exposed to 1,25(OH)(2)D(3) 0.5nM was detected. CONCLUSIONS: In breast cancer specimens a short period of 1,25(OH)(2)D(3) exposure at near physiological concentration modestly activates the hormone transcriptional pathway. Induction of CYP24A1, CA2, DPP4, IL1RL1 expression appears to reflect 1,25(OH)(2)D(3) effects in epithelial as well as stromal cells, however, induction of CD14 expression is likely restricted to the epithelial compartment.

Transcriptional profile and response to neoadjuvante chemotherapy in breast cancer.

OBJECTIVE: To improve the accuracy predictive models of response to neoadjuvante chemotherapy in breast cancer, cDNA microarray technology was used to study tumor transcriptional profile. Gene signatures associated with predicting the response to neoadjuvante chemotherapy are the subject of this review. METHODS: The data base http://www.ncbi.nlm.nih.gov/pubmed/ search was conducted by using the words "breast cancer" AND "neoadjuvante/primary chemotherapy" AND "gene expression profile/microarray". After excluding the repeats and selecting the publications considered most relevant by the authors to be presented, 279 publications were retrieved. RESULTS: The number of publications regarding this subject has been increasing over the years, reaching over 50 in 2010, including the response to different chemotherapeutic drugs, such as anthracyclines and taxanes either alone or in combination. The first studies are from early last decade and used microarray platforms produced by the investigators. Recent studies have used commercial microarray platforms whose data have been stored in public databases, allowing for the analysis of a higher number of samples. Several transcriptional profiles associated with the complete pathological response were identified. Other authors used the clinical response to treatment as an endpoint, and, in this case, a predictive panel of resistance to the chemotherapeutic regimen at issue was determined. This is also a key issue, as it can contribute to individualize treatment, allowing patients resistant to a certain chemotherapeutic agent to be offered another therapeutic regimen. CONCLUSION: Identifying patients responsive to chemotherapy is of essential interest and despite major steps have been taken, the issue warrants further studies in view of its complexity.

Perfil transcricional e resposta à quimioterapia neoadjuvante em câncer de mama / Transcriptional profile and response to neoadjuvante chemotherapy in breast cancer

OBJETIVO: Na tentativa de melhorar a acurácia dos modelos preditivos de resposta à quimioterapia neoadjuvante em câncer de mama, utilizou-se a tecnologia de cDNA microarray para determinar o perfil transcricional dos tumores. A avaliação de assinaturas gênicas, associadas à predição de resposta à quimioterapia neoadjuvante, é o objeto desta revisão. MÉTODOS: Foi realizada busca no banco de dados eletrônico http://www.ncbi.nlm.nih.gov/pubmed/, usando as palavras "breast cancer" AND "neoadjuvant/primary chemotherapy" AND "gene expression profile/microarray". Recuperaram-se 279 publicações, excluindo-se as repetições, selecionando-se para exposição aquelas consideradas mais relevantes pelos autores. RESULTADOS: O número de publicações acerca desse assunto vem crescendo ao longo dos anos, chegando a mais de 50 em 2010, abordando resposta a diferentes quimioterápicos como antraciclinas, taxanos, isoladamente ou em associação. Os primeiros estudos são do início da década passada e utilizaram plataformas de microarray produzidas pelos pesquisadores. Trabalhos mais recentes utilizam plataformas de microarray comerciais, cujos dados são depositados em bancos públicos, permitindo análise de um número maior de amostras. Foram identificados vários perfis transcricionais associados à resposta patológica completa. Outros autores utilizaram como desfecho a resposta clínica ao tratamento, determinando, nesse caso, um painel preditivo de resistência ao esquema quimioterápico em questão. Essa questão também é fundamental, pois pode contribuir para individualizar o tratamento, permitindo que pacientes resistentes a determinado agente quimioterápico sejam submetidos a outro esquema terapêutico. CONCLUSÃO: A identificação de pacientes responsivos à quimioterapia é de fundamental interesse e, apesar de passos importantes terem sido dados, o assunto merece estudos adicionais em vista de sua complexidade.

OBJECTIVE: To improve the accuracy predictive models of response to neoadjuvante chemotherapy in breast cancer, cDNA microarray technology was used to study tumor transcriptional profile. Gene signatures associated with predicting the response to neoadjuvante chemotherapy are the subject of this review. METHODS: The data base http://www.ncbi.nlm.nih.gov/pubmed/ search was conducted by using the words "breast cancer" AND "neoadjuvante/primary chemotherapy" AND "gene expression profile/microarray". After excluding the repeats and selecting the publications considered most relevant by the authors to be presented, 279 publications were retrieved. RESULTS: The number of publications regarding this subject has been increasing over the years, reaching over 50 in 2010, including the response to different chemotherapeutic drugs, such as anthracyclines and taxanes either alone or in combination. The first studies are from early last decade and used microarray platforms produced by the investigators. Recent studies have used commercial microarray platforms whose data have been stored in public databases, allowing for the analysis of a higher number of samples. Several transcriptional profiles associated with the complete pathological response were identified. Other authors used the clinical response to treatment as an endpoint, and, in this case, a predictive panel of resistance to the chemotherapeutic regimen at issue was determined. This is also a key issue, as it can contribute to individualize treatment, allowing patients resistant to a certain chemotherapeutic agent to be offered another therapeutic regimen. CONCLUSION: Identifying patients responsive to chemotherapy is of essential interest and despite major steps have been taken, the issue warrants further studies in view of its complexity.

Influence of the interaction between nodal fibroblast and breast cancer cells on gene expression.

Our aim was to evaluate the interaction between breast cancer cells and nodal fibroblasts, by means of their gene expression profile. Fibroblast primary cultures were established from negative and positive lymph nodes from breast cancer patients and a similar gene expression pattern was identified, following cell culture. Fibroblasts and breast cancer cells (MDA-MB231, MDA-MB435, and MCF7) were cultured alone or co-cultured separated by a porous membrane (which allows passage of soluble factors) for comparison. Each breast cancer lineage exerted a particular effect on fibroblasts viability and transcriptional profile. However, fibroblasts from positive and negative nodes had a parallel transcriptional behavior when co-cultured with a specific breast cancer cell line. The effects of nodal fibroblasts on breast cancer cells were also investigated. MDA MB-231 cells viability and migration were enhanced by the presence of fibroblasts and accordingly, MDA-MB435 and MCF7 cells viability followed a similar pattern. MDA-MB231 gene expression profile, as evaluated by cDNA microarray, was influenced by the fibroblasts presence, and HNMT, COMT, FN3K, and SOD2 were confirmed downregulated in MDA-MB231 co-cultured cells with fibroblasts from both negative and positive nodes, in a new series of RT-PCR assays. In summary, transcriptional changes induced in breast cancer cells by fibroblasts from positive as well as negative nodes are very much alike in a specific lineage. However, fibroblasts effects are distinct in each one of the breast cancer lineages, suggesting that the inter-relationships between stromal and malignant cells are dependent on the intrinsic subtype of the tumor.