In vivo human melanoma cytokine production: inverse correlation of GM-CSF production with tumor depth

Shared Gene Expression and Immune Pathway Changes Associated with Progression from Nevi to Melanoma

Simple Summary

Melanoma is a deadly skin cancer, and the incidence of melanoma is rising. Chemoprevention, using small molecule drugs to prevent the development of cancer, is a key strategy that could reduce the burden of melanoma on society. The long-term goal of our study is to develop a gene signature biomarker of progression from nevi to melanoma. We found that a small number of genes can distinguish nevi from melanoma and identified shared genes and immune-related pathways that are associated with progression from nevi to melanoma across independent datasets. This study demonstrates (1) a novel approach to aid melanoma chemoprevention trials by using a gene signature as a surrogate endpoint and (2) the feasibility of determining a gene signature biomarker of melanoma progression.

Abstract

There is a need to identify molecular biomarkers of melanoma progression to assist the development of chemoprevention strategies to lower melanoma incidence. Using datasets containing gene expression for dysplastic nevi and melanoma or melanoma arising in a nevus, we performed differential gene expression analysis and regularized regression models to identify genes and pathways that were associated with progression from nevi to melanoma. A small number of genes distinguished nevi from melanoma. Differential expression of seven genes was identified between nevi and melanoma in three independent datasets. C1QB, CXCL9, CXCL10, DFNA5 (GSDME), FCGR1B, and PRAME were increased in melanoma, and SCGB1D2 was decreased in melanoma, compared to dysplastic nevi or nevi that progressed to melanoma. Further supporting an association with melanomagenesis, these genes demonstrated a linear change in expression from benign nevi to dysplastic nevi to radial growth phase melanoma to vertical growth phase melanoma. The genes associated with melanoma progression showed significant enrichment of multiple pathways related to the immune system. This study demonstrates (1) a novel application of bioinformatic approaches to aid clinical trials of melanoma chemoprevention and (2) the feasibility of determining a gene signature biomarker of melanomagenesis.

Breast Cancer Cell-Derived GM-CSF Licenses Regulatory Th2 Induction by Plasmacytoid Predendritic Cells in Aggressive Disease Subtypes

Reciprocal interactions between tumor cells and their microenvironment vitally impact tumor progression. In this study, we show that GM-CSF produced by primary breast tumor cells induced the activation of plasmacytoid predendritic cells (pDC), a cell type critical to anti-viral immunity. pDC that expressed the GM-CSF receptor were increased in breast tumors compared with noninvolved adjacent breast tissue. Tumor-activated pDC acquired naïve CD4(+) T-cell stimulatory capacity and promoted a regulatory Th2 response. Finally, the concomitant increase of GM-CSF and pDC was significantly associated with relatively more aggressive breast cancer subtypes. Our results characterize the first tumor-derived factor that can activate pDC to promote a regulatory Th2 response, with implications for therapeutic targeting of a tumor-immune axis of growing recognition in its significance to cancer.

Biomarkers: the useful and the not so useful--an assessment of molecular prognostic markers for cutaneous melanoma

Among individuals with localized (Stage I-II) melanoma, stratifying patients by a number of phenotypic variables (e.g., depth of invasion, ulceration) yields a wide range of 10-year melanoma-specific survival rates. With the possible exception of Ki-67, no molecular assessment is routinely used. However, there have been a tremendous number of studies assessing protein expression by immunohistochemistry toward the goal of better prediction of recurrence. In a previous systematic review, which required publication of multivariable prognostic models as a strict inclusion criterion, we identified 37 manuscripts that collectively reported on 62 proteins. Data for 324 proteins extracted from 418 manuscripts did not meet our inclusion criteria for that study, but are revisited here, emphasizing trends of protein expression across either melanocytic lesion progression or gradations of tumor thickness. These identified 101 additional proteins that stratify melanoma, organized according to the Hanahan and Weinberg functional capabilities of cancer.

Differential expression of the chemokines GRO-2, GRO-3, and interleukin-8 in colon cancer and their impact on metastatic disease and survival

BACKGROUND AND AIM

Chemotactic cytokines play a role in angiogenesis and attraction of immune cells. However, their contribution to tumor formation remains incompletely understood. In a previous transcriptome study, we identified a family of structurally related chemokines of the CXC-family to be specifically up-regulated in colorectal cancer. The aim of the present study was to investigate the regulation of their expression in colon cancer cells and to test the hypothesis that altered CXC-chemokine expression is related to critical clinical parameters, such as survival or metastasis formation.

MATERIALS AND METHODS

Expression levels of interleukin-8 (CXCL-8) and growth-related oncogenes 2 and 3 (GRO-2/CXCL-2 and GRO-3/CXCL-3) were quantified using qRT-PCR in 97 patients with completely resected colon carcinoma and correlated with clinical parameters. Moreover, 16 samples of normal mucosa, nine samples of benign adenoma, and 11 samples of liver metastasis were analyzed. Next, the regulation of chemokine expression in response to various stimuli was tested in colon cancer cell lines (HT29, HCT116, CaCO2).

RESULTS

Expression of GRO-2, GRO-3, and IL-8 was significantly increased in colon cancer as compared to normal colon tissue. Expression of GRO-2 and GRO-3 was already enhanced in premalignant adenomas, and GRO-3 was significantly down-regulated in liver metastasis as compared to the primary tumor. Importantly, expression of GRO-3 was significantly higher in patients with local versus systemic disease. Moreover, IL-8 expression was significantly associated to overall post-operative survival. Finally, all chemokines were strongly induced by IL-1alpha in the colon cancer cell lines tested, indicating a potential link to inflammatory processes.

CONCLUSION

In accordance with earlier findings, we report here a significantly increased expression of GRO-2, GRO-3, and IL-8 in colon carcinoma as compared to normal tissue. Furthermore, GRO-3 was related to metastasis formation, and IL-8 was associated with survival, suggesting a potential predictive power of these markers.

CXCL8 and its cognate receptors in melanoma progression and metastasis

The incidence of melanoma is rising at an alarming rate and we are still awaiting an effective treatment for this malignancy. In its early stage, melanoma can be cured by surgical removal, but once metastasis has occurred there is no effective treatment. Recent findings have suggested multiple functional implications of CXCL8 and its cognate receptors, CXCR1 and CXCR2, in melanoma pathogenesis, thus underscoring their importance as targets for cancer therapy. This review provides an update on the roles of CXCL8 and its receptors in melanoma progression and metastasis.

Immune modulation by melanoma-derived factors

Melanomas, while the less common of skin cancers, are highly aggressive and once they metastasize usually indicate a poor prognosis. Melanomas are in many cases immunogenic and thus have been a prime target for immunotherapy, which has resulted in objective responses in some patients. To understand why antitumor immunity fails, and for the purpose of discovering new targets to improve therapy, there has been great interest to analyse the antitumor immune responses which exist in these patients, and uncover mechanisms which block tumor-specific immune responses. It is now evident that immunosuppressive cell networks and factors play a major role in the failure of the antitumor immune responses and therapies to eradicate the tumor. In this review, the factors produced by melanomas which can modulate and enhance these suppressive mechanisms are discussed. The roles of immature dendritic cells, neutrophils, T-regulatory cells, myeloid-derived suppressor cells and M2 macrophages or tumor-associated macrophages are described. Furthermore, taking into consideration of the cross-talk which exists among these different cell types and the cycle of immunosuppression which is evident in melanoma cancer patients and animal models, will be important for future therapeutic approaches.

Correlation of IL-8 with induction, progression and metastatic potential of colorectal cancer

AIM: To investigate the expression profile of IL-8 in inflammatory and malignant colorectal diseases to evaluate its potential role in the regulation of colorectal cancer (CRC) and the development of colorectal liver metastases (CRLM).

METHODS: IL-8 expression was assessed by quantitative real-time PCR (Q-RT-PCR) and the enzyme-linked immunosorbent assay (ELISA) in resected specimens from patients with ulcerative colitis (UC, n = 6) colorectal adenomas (CRA, n = 8), different stages of colorectal cancer (n = 48) as well as synchronous and metachronous CRLM along with their corresponding primary colorectal tumors (n = 16).

RESULTS: IL-8 mRNA and protein expression was significantly up-regulated in all pathological colorectal entities investigated compared with the corresponding neighboring tissues. However, in the CRC specimens IL-8 revealed a significantly more pronounced overexpression in relation to the CRA and UC tissues with an average 30-fold IL-8 protein up-regulation in the CRC specimens in comparison to the CRA tissues. Moreover, IL-8 expression revealed a close correlation with tumor grading. Most interestingly, IL-8 up-regulation was most enhanced in synchronous and metachronous CRLM, if compared with the corresponding primary CRC tissues. Herein, an up to 80-fold IL-8 overexpression in individual metachronous metastases compared to normal tumor neighbor tissues was found.

CONCLUSION: Our results strongly suggest an association between IL-8 expression, induction and progression of colorectal carcinoma and the development of colorectal liver metastases.

Complete remission of brain metastases in three patients with stage IV melanoma treated with BOLD and G-CSF

BACKGROUND

Brain metastases are the most life-threatening among the secondary localizations of melanoma for their unresponsiveness to the surgical, radiotherapeutic and/or chemotherapeutic treatments.

METHODS

Accidentally, we observed a complete response (CR) in a patient undergoing chemotherapy with bleomycin, vincristine or Oncovin, CCNU or lomustine, dacarbazine (BOLD) regimen for metastatic melanoma including brain metastases, who was also treated with G-CSF to manage a concomitant leukopenia. After this observation, seven more patients with stage IV melanoma with brain metastases were treated with BOLD regimen repeated every 6 weeks with administration of G-CSF in the intervals.

RESULTS

Three patients presented CR (37.5%). Two patients stopped the treatment after two courses for evident progressive disease (25%). The other three patients showed stable disease (SD: 37.5%). Median duration of SD was 24 weeks. Among the eight patients, six (75%) achieved clinical benefit. Median time to progression was 8.5 months (range 0-74+ months). Median survival was 12.5 months (range 4-74+ months). Two patients are still alive and disease-free after 74 and 57 months, respectively.

CONCLUSION

We believe that the brilliant CR, the long duration of the disease-free intervals and the long survival in at least three of eight patients should encourage further research on BOLD with G-CSF for the treatment of advanced melanoma.

Complete tumor prevention by engineered tumor cell vaccines employing nonviral vectors

We report that 100% mice survival after tumor challenge is achieved with cytokine-engineered cells employing nonviral lipoplexes and without using viral vectors. We describe this effect with cytokine-secreting tumor cell vaccines, based on cell clones or fresh transfected cells. Tumor cells were transfected with murine granulocyte-macrophage colony-stimulating factor (GM-CSF) or IL-4 plasmids employing the cationic lipid DOTAP, were irradiated (150 Gy) and kept frozen until use. The transfection efficacy was analyzed by qRT-PCR and flow cytometry. Vaccination induced potent antitumor rejection, resulting in 100% mice survival. Furthermore, the antitumor immunity was long lasting, since a two-fold survival delay was observed in mice after tumor rechallenge (6 months later). While cell clones secreting GM-CSF were the most effective in wild-type tumor cell rejection, little or no effect was observed with clones secreting IL-4. We found similar antitumor efficacy employing fresh transfected cells by nonviral procedures, demonstrating that cells genetically modified by nonviral vectors (both clones and fresh transfected cells) are a safe and efficient tool for antitumor vaccines. These vaccines allow us to achieve the highest antitumor efficacy based on nonviral gene therapy techniques. In addition, the vaccination success with fresh transfected cells simplifies the procedure and provides new insights into the clinical application of nonviral gene therapy procedures.

Interleukin-8 and human cancer biology

The aggressive nature of metastatic human cancer has been shown to be related to numerous abnormalities in growth factors and their receptors. These perturbations confer a tremendous growth advantage to the malignant cells. Interleukin-8 (IL-8), originally discovered as a chemotactic factor for leukocytes, has recently been shown to contribute to human cancer progression through its potential functions as a mitogenic, angiogenic, and motogenic factor. While it is constitutively detected in human cancer tissues and established cell lines, IL-8 expression is regulated by various tumor microenvironment factors, such as hypoxia, acidosis, nitric oxide, and cell density. Understanding the mechanisms of both inducible and constitutive IL-8 expression will be helpful in designing potential therapeutic strategies of targeting IL-8 to control tumor growth and metastasis. In this review, the role and regulation of IL-8 expression in the growth and metastasis of human cancer with a focus on human pancreatic adenocarcinoma will be discussed.

Management of high-risk melanoma

Improved treatment options for patients with high-risk melanoma are of great importance for clinicians who participate in the care of these patients. There remains an overall lack of response to existing treatment options, which continues to fuel the efforts of basic scientists and clinicians to pursue other approaches for the treatment of melanoma that is no longer limited to the skin. Continued investigation into the innovative and concurrent use of surgery, chemotherapy, immunotherapy, and radiation therapy holds significant promise for improved outcomes in the management of patients with this devastating disease.