Inflammatory Tumor Progression Research Articles

Mild dyslipidemia accelerates tumorigenesis through expansion of Ly6Chi monocytes and differentiation to pro-angiogenic myeloid cells

Cancer and cardiovascular disease (CVD) share common risk factors such as dyslipidemia, obesity and inflammation. However, the role of pro-atherogenic environment and its associated low-grade inflammation in tumor progression remains underexplored. Here we show that feeding C57BL/6J mice with a non-obesogenic high fat high cholesterol diet (HFHCD) for two weeks to induce mild dyslipidemia, increases the pool of circulating Ly6Chi monocytes available for initial melanoma development, in an IL-1β-dependent manner. Descendants of circulating myeloid cells, which accumulate in the tumor microenvironment of mice under HFHCD, heighten pro-angiogenic and immunosuppressive activities locally. Limiting myeloid cell accumulation or targeting VEGF-A production by myeloid cells decrease HFHCD-induced tumor growth acceleration. Reverting the HFHCD to a chow diet at the time of tumor implantation protects against tumor growth. Together, these data shed light on cross-disease communication between cardiovascular pathologies and cancer.

Adult Human Glioblastomas Harbor Radial Glia-like Cells.

SummaryRadial glia (RG) cells are the first neural stem cells to appear during embryonic development. Adult human glioblastomas harbor a subpopulation of RG-like cells with typical RG morphology and markers. The cells exhibit the classic and unique mitotic behavior of normal RG in a cell-autonomous manner. Single-cell RNA sequencing analyses of glioblastoma cells reveal transcriptionally dynamic clusters of RG-like cells that share the profiles of normal human fetal radial glia and that reside in quiescent and cycling states. Functional assays show a role for interleukin in triggering exit from dormancy into active cycling, suggesting a role for inflammation in tumor progression. These data are consistent with the possibility of persistence of RG into adulthood and their involvement in tumor initiation or maintenance. They also provide a putative cellular basis for the persistence of normal developmental programs in adult tumors.

Comparison of the Prognostic Impact of Neutrophil/Lymphocyte Ratio, Platelet/Lymphocyte Ratio, and Glasgow Prognostic Score in Diffuse Large B-Cell Lymphoma

Background: Given the role of inflammation in tumor progression, as well as in diffuse large B-cell lymphoma (DLBCL), researchers are trying to identify easily applicable, easy accessible prognostic markers for individual risk assessment. The most frequently used inflammatory prognostic markers are the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR),andthe Glasgow prognostic score (GPS). Objectives: To determine and compare the prognostic value of the baseline inflammatory biomarkers NLR, PLR, and GPS in patients with DLBCL. Methods: We retrospectively analyzed data from 103 DLBCL patients treated with R-CHOP or R-CHOP-like regimens. We evaluated the significance of NLR, PLR, and GPS as a predictor of response to treatment, overall survival (OS), and event-free survival (EFS). Results: Higher NLR levels were found in patients with a poorer response to therapy (median [range] 2.87 [0.56 - 26.33] vs. 4 [0.62 - 29.66], P = 0.026). Patients with NLR values of > 2.63 (cutoff value calculated by receiver-operating characteristic) had significantly worse two-year OS (65.1% vs. 87.2%, P = 0.002) and two-year EFS (59.8% vs. 87.1%, P = 0.001). PLR values were not significant for survival. The two-year OS rates for patients with GPS = 0, GPS = 1, and GPS = 2 were 93.3%, 63.9%, and 33.3%, respectively (P 2.63 were an independent prognostic factor for OS (hazard ratio [HR] = 2.857; 95% confidence interval [CI] 1.022 - 8.699; P = 0.048] and EFS (HR = 4.06; 95% CI 1.357 - 12.151; P = 0.012). Conclusions: Our research confirmed NLR as useful independent prognostic marker for survival. PLR and GPS did not show independent prognostic value, although they were also associated with the patients’ clinical features. The easy availability and inexpensiveness of inflammatory biomarkers should encourage their use in clinical practice.

MicroRNA MIR21 (miR-21) and PTGS2 Expression in Colorectal Cancer and Patient Survival.

Prostaglandin-endoperoxide synthase 2 (PTGS2, cyclooxygenase-2; a target of aspirin) produces inflammatory mediator prostaglandin E2 (PGE2), and contributes to colorectal neoplasia development. PTGS2-driven inflammatory responses can induce tumor expression of microRNA MIR21 (miR-21) that can increase local PGE2 level by downregulating PGE2-metabolizing enzymes. We hypothesized that the prognostic association of tumor MIR21 expression level in colorectal carcinoma might depend on inflammatory tumor microenvironment and be stronger in tumors expressing high-level PTGS2. Utilizing 765 rectal and colon cancer specimens in the Nurses' Health Study and the Health Professionals Follow-up Study, we measured MIR21 expression by quantitative reverse transcription PCR, and PTGS2 expression by immunohistochemistry. Cox proportional hazards regression model was used to assess statistical interaction between MIR21 and PTGS2 in colorectal cancer-specific survival analysis, controlling for potential confounders including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation level, and KRAS, BRAF, and PIK3CA mutations. Tumor MIR21 expression level was associated with higher colorectal cancer-specific mortality (Ptrend = 0.029), and there was a statistically significant interaction between MIR21 and PTGS2 (Pinteraction = 0.0004). The association between MIR21 expression and colorectal cancer-specific mortality was statistically significant in PTGS2-high cancers (multivariable hazard ratio of the highest vs. lowest quartile of MIR21, 2.28; 95% confidence interval, 1.42-3.67; Ptrend = 0.0004) but not in PTGS2-absent/low cancers (Ptrend = 0.22). MIR21 expression level in colorectal carcinoma is associated with worse clinical outcome, and this association is stronger in carcinomas expressing high-level PTGS2, suggesting complex roles of immunity and inflammation in tumor progression. Clin Cancer Res; 22(15); 3841-8. ©2016 AACR.

Abstract 4554: Toll-like receptor expression and ligation promotes in vitro invasion in pancreatic cancer

Abstract Introduction: Pancreatic cancer (PC) has the worst prognosis of all the major cancers. The role of inflammation in tumor progression and metastasis, particularly in PC, is widely accepted. Our lab has recently shown that levels of circulating cell-free DNA (cfDNA) and associated proteins (histones, HMGB-1, etc.) are elevated in PC patients at baseline and increase in response to standard therapies. It is also known that components of the innate immune system respond to cfDNA and associated proteins. Specifically, the toll-like receptors (TLRs) have been shown to be activated by cfDNA and associated proteins. These TLRs, specifically TLR-4 and TLR-9, have been shown to promote tumor progression and metastasis in other cancers such as breast, colorectal, and skin cancers. We wanted to investigate the role of TLRs in PC by characterizing receptor expression and downstream function. We also attempted to inhibit the downstream effects of TLR signaling using nucleic acid binding polymers (NABPs) that our lab has previously utilized in other disease models such as systemic lupus erythematosus. Methods: Three human (MiaPaCa-2, BxPC-3, PANC-1) and one murine (KPC-4580P) PC cell line were characterized for TLR-4 and TLR-9 expression by western blot. Briefly, cells were plated and lysed using RIPA buffer. Total protein concentration was quantified using bicinchoninic acid (BCA) assay and normalized prior to running the cell lysates on SDS-PAGE. The protein bands were then transferred to immunoblotting membrane and probed with specific primary antibodies, followed by fluorescent secondary antibodies. Blots were exposed and quantified via LI-COR. Downstream function of TLR expression was tested using Transwell-matrigel invasion assays wherein cells were plated in the Transwell system in the presence of TLR-4 and TLR-9 specific agonists (LPS and CpG or mtDNA, respectively). These cells were also treated with NABPs to inhibit TLR activation. Results: All PC cell lines expressed TLR-4 and TLR-9. The invasion assays indicated that in the presence of TLR-4 and TLR-9 specific agonists, PC cells exhibited increased invasion. Moreover, PC cells that invaded in response to TLR-9 agonists were inhibited in the presence of NABPs. Our lab has also prepared conditioned media (CM) from cells treated with clinically relevant doses of radiation. Our PC cell lines displayed increased invasiveness in response to CM and decreased with NABP treatment. Conclusion: We have previously shown that there are elevated levels of cfDNA and associated proteins in PC patient serum and have now shown that these factors can have direct effects on PC cells via TLRs that are expressed by the cancer cells. Treating cells with NABPs in the presence of TLR agonists can abrogate TLR mediated invasion in vitro. Our goal is to further characterize the effects of TLR signaling on cancer cells including RNA transcription and protein translation profiling. Citation Format: Ibtehaj A. Naqvi, Jessica McDade, Jaewoo Lee, Rebekah White. Toll-like receptor expression and ligation promotes in vitro invasion in pancreatic cancer. [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 4554.

A framework for the role of acute inflammation in tumor progression.

Breast cancer remains the second leading cancer-related death in women in the United States. Despite improvements in early detection, prevention, and treatment, the mortality rate in breast cancer remains high secondary to the potential for cancer recurrence and the development of metastasis. To minimize breast cancer-related morbidity and mortality, understanding the factors leading to an increased risk of metastasis and developing clinical interventions that reduce this risk is essential. While the association between chronic inflammation and cancer progression is well documented in the literature, the role of acute inflammation and its impact on tumor proliferation and metastasis is less well understood. Here, we will review recently published preclinical studies in mouse models indicating that acute inflammation caused by clinical interventions plays an important role in the risk of peripheral metastases. In addition, we will address the potential impact that these findings may have on the clinical management of breast cancer.

Tertiary lymphoid structures are associated with higher tumor grade in primary operable breast cancer patients.

BackgroundTertiary lymphoid structures (TLS) are highly organized immune cell aggregates that develop at sites of inflammation or infection in non-lymphoid organs. Despite the described role of inflammation in tumor progression, it is still unclear whether the process of lymphoid neogenesis and biological function of ectopic lymphoid tissue in tumors are beneficial or detrimental to tumor growth. In this study we analysed if TLS are found in human breast carcinomas and its association with clinicopathological parameters.MethodsIn a patient group (n = 290) who underwent primary surgery between 2011 and 2012 we assessed the interrelationship between the presence of TLS in breast tumors and clinicopathological factors. Prognostic factors were entered into a binary logistic regression model for identifying independent predictors for intratumoral TLS formation.ResultsThere was a positive association between the grade of immune cell infiltration within the tumor and important prognostic parameters such as hormone receptor status, tumor grade and lymph node involvement. The majority of patients with high grade infiltration of immune cells had TLS positive tumors. In addition to the degree of immune cell infiltration, the presence of TLS was associated with organized immune cell aggregates, hormone receptor status and tumor grade. Tumors with histological grade 3 were the strongest predictor for the presence of TLS in a multivariate regression model. The model also predicted that the odds for having intratumoral TLS formation were ten times higher for patients with high grade of inflammation than low grade.ConclusionsHuman breast carcinomas frequently contain TLS and the presence of these structures is associated with aggressive forms of tumors. Locally generated immune response with potentially antitumor immunity may control tumorigenesis and metastasis. Thus, defining the role of TLS formation in breast carcinomas may lead to alternative therapeutic approaches targeting the immune system.

NADPH oxidase 1-dependent ROS is crucial for TLR4 signaling to promote tumor metastasis of non-small cell lung cancer.

Recent evidence demonstrated an enhanced metastasis of non-small cell lung cancer (NSCLC) cells induced by lipopolysaccharide (LPS) stimulation, which reflected an important role of inflammation in tumor progression. However, the underlying mechanisms still remain unclear. Here, we evaluated the potential role of reactive oxygen species (ROS) in Toll-like receptor 4 (TLR4) signaling enhanced NSCLC metastasis. NSCLC cells were isolated from clinical surgical tissues. We found that LPS stimulation of NSCLC cells facilitates their metastasis that was accompanied by increased ROS production and could be abrogated by ROS inhibition. NADPH oxidase was essential for TLR4 signaling-enhanced NSCLC metastasis. Elevated NADPH oxidase 1 (NOX1) expression by LPS stimulation was observed. Blockade of NOX1 with ML171 alleviated enhanced NSCLC metastasis by TLR4 signaling. Enforced NOX1 expression promoted TLR4 signaling-enhanced NSCLC metastasis, while decreased NOX1 expression inhibited TLR4 signaling-enhanced NSCLC metastasis. Further, NOX1 could regulate the expression of CXCR4 and matrix metallopeptidase 9 (MMP9) in NSCLC cells. NOX1 expression in tumor tissues was correlated with TLR4 expression and clinical stages in NSCLC patients. Finally, inhibition of NOX1/ROS prevented enhanced lung tumor burdens of NSCLC by LPS-induced acute lung infection. Our findings demonstrated a crucial role of NOX1-dependent ROS for TLR4 signaling to enhance the metastasis of NSCLC, which could further the understanding of NSCLC pathogenesis and helpful for developing novel therapeutics for NSCLC.

The pan-cancer analysis of gene expression patterns in the context of inflammation.

Although several studies have investigated the essential roles of inflammation in tumor progression, not many have systematically analyzed gene expression patterns across diverse cancers in the context of inflammation. In this study, in order to better understand the inflammatory scenario, we initially constructed the inflammatory timeline (IT) based on two gene expression profiles during inflammatory progression (inflammatory bowel disease and Helicobacter pylori infection). Then, we separately identified the differentially expressed genes (DEGs) from 25 cancer-related microarray data. By comparing the distributions of DEGs in the IT, we identified three novel pan-cancer gene expression patterns. In the first pattern, the up-regulated genes in cancers were over-expressed in the early phase of inflammation, while the down-regulated genes were over-expressed in the late phase of inflammation. The second pattern was the opposite of the first one. The third pattern appeared to be transitional between the first and second patterns. We found that some cancers with different tissue origins have similar gene expression patterns. Finally, we identified two sets of tissue-independent inflammatory signatures that were over-expressed in early and late phases of inflammation, respectively. The dominant biological processes of early inflammatory signatures were cell proliferation, DNA replication, and DNA repair, whereas the late inflammatory signatures were reflective of innate immune response, neutrophil migration, and antigen processing. These inflammatory signatures may be useful to predict gene expression patterns in human cancers. Therefore, the pan-cancer analysis of gene expression patterns in the context of inflammation provides a novel insight into cancers and an unprecedented opportunity to develop new therapies.

Abstract 392: The role of post surgical inflammation in tumor progression in breast cancer

Abstract Introduction The process of chronic inflammation inducing malignant transformation is well known and recognized in several disease states, including ulcerative colitis (colorectal carcinoma), chronic wounds (squamous cell carcinoma), and hepatitis B infection (hepatocellular carcinoma) as common examples. Recent evidence suggests that this process may be relevant in other tumor types and may be influenced by inflammation arising secondary to interventional procedures. The purpose of this study is to investigate the potential role of inflammatory mediators resulting from the post-surgical healing process on tumor proliferation and progression to metastasis in breast cancer. Methods We used MMTV-PyV MT female mice (transgenic mice expressing the middle T antigen of the polyomavirus under the control of the MMTV promoter/enhancer) as a mouse model of human epidermal breast cancer. Mice underwent a surgical punch biopsy (2 mm) in the center of the tumor, or underwent the same procedure (transient anesthesia) without biopsy. Mice were paired according to the tumor size at the time of biopsy. Mice were then euthanized 8 days after biopsy, and lungs were harvested and histologically examined for the presence of micrometastases. To further evaluate the effect of inflammation in the development of metastases, a separate subset of mice were treated with ibuprofen versus vehicle (placebo control) for three days after biopsy. Results No substantial difference in the primary tumor growth was observed after biopsy between the various groups. However, a greater number of metastases were found in the lungs of mice that underwent biopsy relative to the number in mice that did not receive biopsy. The number of metastases was reduced in the set of mice receiving ibuprofen treatment following the biopsy procedure (9.3 vs. 25 p<0.05). Conclusion Our study provides evidence to suggest that inflammatory mediators arising secondary to the healing process may stimulate tumor proliferation and metastasis. These findings may hold significance for the timing of breast cancer treatment following diagnostic needle biopsy, as well as for the potential impact of excisional biopsy on the outcome of patients with breast cancer. Further research into the mechanisms of this interaction may help to increase our understanding of breast cancer biology and may yield new strategies (e.g. anti-inflammatory medication) to optimize treatment and outcome. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 392. doi:1538-7445.AM2012-392

Dualistic role of tumor‐directed antibodies on carcinoma progression

Immunosurveillance and immunoediting of tumors comprise immune reactions that check and destroy cancer cells, and form the basis of cancer immunotherapy strategies. Paradoxically, immune reactions can also facilitate tumor progression, i.e. the immune response has a dualistic role. It is currently unclear what range of immune response defines the ends of this spectrum for a given tumor. We addressed this question using a humanized murine model in which antibodies against a human‐specific tumor antigen alters progression of tumors bearing the antigen. Tumor growth was stimulated or inhibited over a linear and narrow dose range defining an immune response curve (IRC), i.e., inverse hormesis. Tuning the relative activity of one or more immune reactants further demonstrated the dualistic role of inflammation in tumor progression. The results have implications for the etiology, prevention and treatment of human cancer. This work is supported by a Samuel and Ruth Engelberg/Cancer Research Institute fellowship and the NIH.

Tertiary Intratumor Lymphoid Tissue in Colo-Rectal Cancer

Ectopic (or tertiary) lymphoid tissue develops at sites of inflammation or infection in non lymphoid organs and is associated with chronic inflammation. In colon mucosa, small lymphoid aggregates are already present in homeostatic conditions, as part of the gut-associated lymphoid tissue and play an essential role in the immune response to perturbations of the mucosal microenvironment. Despite the recognized role of inflammation in tumor progression, the presence and biological function of lymphoid tissue in cancer has been poorly investigated. We identified aggregates of lymphocytes resembling tertiary lymphoid tissue in human colorectal cancer specimens; intratumor accumulations of lymphocytes display a high degree of compartmentalization, with B and T cells, mature dendritic cells and a network of CD21+ follicular dendritic cells (FDC). We analyzed the adaptation of colon lymphoid tissue in a murine model of colitis-associated cancer (AOM/DSS). B cell follicle formation increases in the context of the chronic inflammation associated to intestinal neoplasia, in this model. A network of lymphatic and haematic vessels surrounding B cell follicles is present and includes high endothelial venules (HEV). Future task is to determine whether lymphoid tissue contributes to the persistence of the tumor-associated inflammatory reaction, rather than represent a functional immune compartment, potentially participating to the anti tumor response.

Role of TLR2‐dependent inflammation in metastatic progression

Inflammation is a part of the host defense system, which provides protection against invading pathogens. However, it has become increasingly clear that inflammation can be evoked by endogenous mediators through Toll-like receptors (TLRs) to enhance tumor progression and metastasis. Here, we discuss the roles of TLR-mediated inflammation in tumor progression and the mechanisms through which it accomplishes this pathogenic function.

The Role of Inflammation in Tumor Progression: Targeting Tumor-Associated Macrophages

Current evidence suggests an increasing role for inflammation as a critical link to tumor progression. The host response to a cancer shares many parallels with an infection or a wound. Thus it is not surprising that many tumors arise from areas of infection or chronic inflammation. Tumors have been described as wounds that never heal. The local production of cytokines, including chemokines not only attracts circulating immune cells, but also activates stromal cells in the surrounding microenvironment. Of particular interest are tumor-associated macrophages (TAM). The infiltration of tumors with TAM has been shown to correlate with poor prognosis in several cancers. Recent studies suggest an emerging role for TAM in the remodeling of the tumor microenvironment to support growth and metastasis and support the concept of modifying TAM's responses as novel therapeutic approaches. In this review, we will discuss our current understanding of the role of macrophages, and inflammation in the progression to malign...

Leukocytes, inflammation, and angiogenesis in cancer: fatal attractions

Leukocytes are cells of defense. Their main function is to protect our body against invading microorganisms. Some leukocytes, in particular, polymorphonuclear and monocytes, accumulate at sites of infection and neutralize pathogens through innate mechanisms. The blood and lymphatic vascular system are essential partners in this defensive reaction: Activated endothelial cells promote leukocyte recruitment at inflammatory sites; new blood vessel formation, a process called angiogenesis, sustains chronic inflammation, and lymphatic vessels transport antigens and antigen-presenting cells to lymph nodes, where they stimulate naive T and B lymphocytes to elicit an antigen-specific immune response. In contrast, leukocytes and lymphocytes are far less efficient in protecting us from cancer, the "enemy from within." Worse, cancer can exploit inflammation to its advantage. The role of angiogenesis, leukocytes, and inflammation in tumor progression was discussed at the second Monte Verità Conference, Tumor Host Interaction and Angiogenesis: Basic Mechanisms and Therapeutic Perspectives, held in Ascona, Switzerland, October 1-5, 2005. (Conference chairs were K. Alitalo, M. Aguet, C. Rüegg, and I. Stamenkovic.) Eight articles reporting about topics presented at the conference are featured in this issue of the Journal of Leukocyte Biology.