Crucial biological functions of CCL7 in cancer

Mapping Rora expression in resting and activated CD4+ T cells

The transcription factor Rora has been shown to be important for the development of ILC2 and the regulation of ILC3, macrophages and Treg cells. Here we investigate the role of Rora across CD4+ T cells in general, but with an emphasis on Th2 cells, both in vitro as well as in the context of several in vivo type 2 infection models. We dissect the function of Rora using overexpression and a CD4-conditional Rora-knockout mouse, as well as a RORA-reporter mouse. We establish the importance of Rora in CD4+ T cells for controlling lung inflammation induced by Nippostrongylus brasiliensis infection, and have measured the effect on downstream genes using RNA-seq. Using a systematic stimulation screen of CD4+ T cells, coupled with RNA-seq, we identify upstream regulators of Rora, most importantly IL-33 and CCL7. Our data suggest that Rora is a negative regulator of the immune system, possibly through several downstream pathways, and is under control of the local microenvironment.

Clear Cell Renal Carcinoma: MicroRNAs With Efficacy in Preclinical In Vivo Models

In order to identify new targets and treatment modalities for clear cell renal carcinoma, we surveyed the literature with respect to microRNAs involved in this disease. In this review, we have focused on up- and down-regulated miRs which mediate efficacy in preclinical clear-cell renal carcinoma-related in vivo models. We have identified 10 up-regulated and 33 down-regulated micro-RNAs according to this criterion. As proof-of-concept, micro-RNAs interfering with VEGF (miR-205p) and mTOR (mir-99a) pathways, which are modulated by approved drugs for this disease, have been identified. miRs targeting hypoxia induced factor-2α (HIF-2α) (miR-145), E3 ubiquitinylases speckle-type POZ protein (SPOP) (miR 520/372/373) and casitas B-lineage lymphoma (CBL) (miR-200a-3p), interfere with druggable targets. Further identified miRs interfere with cell-cycle dependent kinases, such as CDK2 (miR-200c), CDK4, 6 (miR-1) and CDK4, 9 (206c). Transmembrane receptor Ral interacting protein of 76 kD (RLIP76), targeted by mir-137, has emerged as another important target for ccRCC. Additional miRs and their targets merrying further preclinical validation are discussed.

Correlation of Tim-3 expression with chemokine levels for predicting the prognosis of patients with glioblastoma

Glioblastoma (GBM) immunotherapy, which blocks the checkpoint inhibitor molecule T cell immunoglobulin domain and mucin domain-3 (Tim-3), has potential therapeutic applications. However, not all patients do benefit from the targeted therapy. This study aimed to explore Tim-3 expression correlated chemokine profiles and immune cell infiltration and investigate their potential as prognostic markers of glioblastoma (GBM) immunotherapy. We analyzed transcriptional data of GBM from TCGA database, to measure Tim-3 expression by R package DESeq2 analysis and observed differentially expressed genes in GBM samples with high Tim-3 expression levels. We also probed the relative gene enrichment pathways. Tim-3 expression was evident in biological processes including the recruitment of immune cells. We also identified some chemokines related to Tim-3 expression. The expression levels of CCL18, CXCL13 and CCL7 were significantly higher in GBM tissues with high Tim-3 expression than in GBM tissues with low Tim-3 expression. In addition, exploring the relationship between immune cell infiltration and Tim-3 expression suggested that Tim-3 expression was positively related to significant immune cell infiltration.

Maternal HIV status skews transcriptomic response in infant cord blood monocytes exposed to Bacillus Calmette--Guerín

OBJECTIVES

HIV-exposed uninfected (HEU) infants exhibit altered vaccine responses and an increased mortality compared with HIV-unexposed infants. Here, vaccine responses in HEU and HIV-unexposed cord blood monocytes (CBMs) were assessed following Bacillus Calmette--Guerín (BCG) treatment.

DESIGN

Innate responses to in-vitro BCG treatment were assessed through transcriptional profiling using CBMs obtained from a Nigerian cohort of HIV-infected and uninfected women.

METHODS

HIV-unexposed (n = 9) and HEU (n = 10) infant CBMs were treated with BCG and transcriptionally profiled with the Nanostring nCounter platform. Differential expression and pathway enrichment analyses were performed, and transcripts were identified with enhanced or dampened BCG responses.

RESULTS

Following BCG stimulation, several pathways associated with inflammatory gene expression were upregulated irrespective of HIV exposure status. Both HIV-unexposed and HEU monocytes increased expression of several cytokines characteristic of innate BCG responses, including IL1β, TNFα, and IL-6. Using differential expression analysis, we identified genes significantly upregulated in HEU compared with HIV-unexposed monocytes including monocyte chemokine CCL7 and anti-inflammatory cytokine TNFAIP6. In contrast, genes significantly upregulated in HIV-unexposed compared with HEU monocytes include chemokine CCL3 and cytokine IL23A, both of which influence anti-mycobacterial T-cell responses. Finally, two genes, which regulate prostaglandin production, CSF2 and PTGS2, were also more significantly upregulated in the HIV-unexposed cord blood indicating that inflammatory mediators are suppressed in the HEU infants.

CONCLUSION

HEU monocytes exhibit altered induction of several key innate immune responses, providing mechanistic insights into dysregulated innate response pathways that can be therapeutically targeted to improve vaccine responses in HEU infants.

Increased Stromal Infiltrating Lymphocytes Are Associated with the Risk of Disease Progression in Mesenchymal Circulating Tumor Cell-Positive Primary Breast Cancer Patients

Circulating tumor cells (CTCs) and the immune infiltration of tumors are closely related to clinical outcomes. This study aimed to verify the influence of stromal lymphocyte infiltration and the immune context of tumor microenvironment on the hematogenous spread and prognosis of 282 chemotherapy naïve primary BC patients. To detect the presence of mesenchymal CTCs, RNA extracted from CD45-depleted peripheral blood was interrogated for the expression of mesenchymal gene transcripts. Tumor-infiltrating lymphocytes (TILs) were detected in the stromal areas by immunohistochemistry, using CD3, CD8, and CD45RO antibodies. The concentrations of 51 plasma cytokines were measured by multiplex bead arrays. TILs infiltration in mesenchymal CTC-positive patients significantly decreased their progression-free survival (HR = 4.88, 95% CI 2.30–10.37, p < 0.001 for CD3^high; HR = 6.17, 95% CI 2.75–13.80, p < 0.001 for CD8^high; HR = 6.93, 95% CI 2.86–16.81, p < 0.001 for CD45RO^high). Moreover, the combination of elevated plasma concentrations of transforming growth factor beta-3 (cut-off 662 pg/mL), decreased monocyte chemotactic protein-3 (cut-off 52.5 pg/mL) and interleukin-15 (cut-off 17.1 pg/mL) significantly increased the risk of disease recurrence (HR = 4.838, 95% CI 2.048–11.427, p < 0.001). Our results suggest a strong impact of the immune tumor microenvironment on BC progression, especially through influencing the dissemination and survival of more aggressive, mesenchymal CTC subtypes.

CCL7 recruits cDC1 to promote antitumor immunity and facilitate checkpoint immunotherapy to non-small cell lung cancer

The efficacy of checkpoint immunotherapy to non-small cell lung cancer (NSCLC) largely depends on the tumor microenvironment (TME). Here, we demonstrate that CCL7 facilitates anti-PD-1 therapy for the Kras^LSL−G12D/+Tp53^fl/fl (KP) and the Kras^LSL−G12D/+Lkb1^fl/fl (KL) NSCLC mouse models by recruiting conventional DC 1 (cDC1) into the TME to promote T cell expansion. CCL7 exhibits high expression in NSCLC tumor tissues and is positively correlated with the infiltration of cDC1 in the TME and the overall survival of NSCLC patients. CCL7 deficiency impairs the infiltration of cDC1 in the TME and the subsequent expansion of CD8⁺ and CD4⁺ T cells in bronchial draining lymph nodes and TME, thereby promoting tumor development in the KP mouse model. Administration of CCL7 into lungs alone or in combination with anti-PD-1 significantly inhibits tumor development and prolongs the survival of KP and KL mice. These findings suggest that CCL7 potentially serves as a biomarker and adjuvant for checkpoint immunotherapy of NSCLC.

Only a limited proportion of patients with non-small cell lung cancer respond to anti-PD-1/PD-L1 immunotherapy. Here, the authors show that in autochthonous models of KRAS-mutated lung cancer, CCL7 promotes cDC1 infiltration into the lungs, sustaining antitumor immune responses and potentiating anti-PD1 treatment efficacy.

High serum CCL20 is associated with tumor progression in penile cancer

Serum cancer biomarker has been proven to be very valuable in cancer diagnosis, disease monitoring and prognosis assessment, despite there is still a lack of serum biomarker for penile cancer (PC). Our initial analysis on public GEO dataset identified CCL20 as a top C-C motif ligand (CCL) gene enriched in PC. The patients with PC exhibited markedly higher preoperative serum CCL20 level than healthy control. The area under the curve (AUC) was 0.855 with the sensitivity of 72.4%, and specificity of 93.5% to distinguish PC. Preoperative serum CCL20 level was significantly associated with clinicopathological characteristics including T stage (P=0.005), nodal status (P=0.008), and pelvic lymph node metastasis (P=0.007). PC Patients with high serum CCL20 level had shorter disease-free survival compared to those with low level (P<0.001). Cox regression analysis showed that serum CCL20 level could serve as an independent prognostic factor for disease-free survival with a HR of 3.980 (95% CI: 1.209-13.098, P=0.023). Furthermore, CCL20 expression was observed in PC tissues and cell lines. Knockdown of CCL20 expression markedly suppressed malignant phenotypes (cell proliferation, clonogenesis, apoptosis escape, migration and invasion), attenuated STAT3 and AKT signaling and reduced MMP2/9 secretion in PC cell lines. Consistently, CCL20 and its receptor CCR6 exhibited correlated expression pattern in PC tissues. In conclusion, serum CCL20 level might serve as a potential diagnostic and prognostic cancer biomarker for PC. CCL20 might activate multiple downstream oncogenic signaling pathways (STAT3, AKT, MMP2/9) to promote malignant progression of PC, which may warrant further investigation in the future.

Safety and Efficacy of Andecaliximab (GS-5745) Plus Gemcitabine and Nab-Paclitaxel in Patients with Advanced Pancreatic Adenocarcinoma: Results from a Phase I Study

BACKGROUND

Matrix metalloproteinase 9 (MMP9) expression in the tumor microenvironment is implicated in multiple protumorigenic processes. Andecaliximab (GS-5745), a monoclonal antibody targeting MMP9 with high affinity and selectivity, was evaluated in combination with gemcitabine and nab-paclitaxel in patients with advanced pancreatic adenocarcinoma.

PATIENTS AND METHODS

This phase I study was completed in two parts: part A was a dose-finding, monotherapy phase that enrolled patients with advanced solid tumors, and part B examined andecaliximab in combination with chemotherapy in specific patient cohorts. In the cohort of patients with pancreatic adenocarcinoma (n = 36), andecaliximab 800 mg every 2 weeks was administered in combination with gemcitabine and nab-paclitaxel. Patients were treated until unacceptable toxicity, withdrawal of consent, disease progression, or death. Efficacy, safety, and biomarker assessments were performed.

RESULTS

Andecaliximab combined with gemcitabine and nab-paclitaxel appeared to be well tolerated and did not demonstrate any unusual toxicities in patients with pancreatic adenocarcinoma. The most common treatment-emergent adverse events were fatigue (75.0%), alopecia (55.6%), peripheral edema (55.6%), and nausea (50.0%). Median progression-free survival was 7.8 months (90% confidence interval, 6.9-11.0) with an objective response rate of 44.4% and median duration of response of 7.6 months. Maximal andecaliximab target binding, defined as undetectable, andecaliximab-free MMP9 in plasma, was observed.

CONCLUSION

Andecaliximab in combination with gemcitabine and nab-paclitaxel demonstrates a favorable safety profile and clinical activity in patients with advanced pancreatic adenocarcinoma.

IMPLICATIONS FOR PRACTICE

The combination of andecaliximab, a novel, first-in-class inhibitor of matrix metalloproteinase 9, with gemcitabine and nab-paclitaxel in patients with advanced pancreatic adenocarcinoma provided a median progression-free survival of 7.8 months and objective response rate of 44.4%. The majority of systemic biomarkers related to matrix metalloproteinase 9 activity and immune suppression increased at 2 months, whereas biomarkers related to tumor burden decreased. Although this study demonstrates promising results with andecaliximab plus chemotherapy in patients with advanced pancreatic adenocarcinoma, andecaliximab was not associated with a survival benefit in a phase III study in patients with advanced gastric/gastroesophageal junction carcinoma.

Molecular and Cellular Factors Associated with Racial Disparity in Breast Cancer

Recent studies have demonstrated that racial differences can influence breast cancer incidence and survival rate. African American (AA) women are at two to three fold higher risk for breast cancer than other ethnic groups. AA women with aggressive breast cancers show worse prognoses and higher mortality rates relative to Caucasian (CA) women. Over the last few years, effective treatment strategies have reduced mortality from breast cancer. Unfortunately, the breast cancer mortality rate among AA women remains higher compared to their CA counterparts. The focus of this review is to underscore the racial differences and differential regulation/expression of genetic signatures in CA and AA women with breast cancer. Moreover, immune cell infiltration significantly affects the clinical outcome of breast cancer. Here, we have reviewed recent findings on immune cell recruitment in the tumor microenvironment (TME) and documented its association with breast cancer racial disparity. In addition, we have extensively discussed the role of cytokines, chemokines, and other cell signaling molecules among AA and CA breast cancer patients. Furthermore, we have also reviewed the distinct genetic and epigenetic changes in AA and CA patients. Overall, this review article encompasses various molecular and cellular factors associated with breast cancer disparity that affects mortality and clinical outcome.

Intestinal epithelial chemokine (C-C motif) ligand 7 overexpression protects against high fat diet-induced obesity and hepatic steatosis in mice

Background

We previously found that the intestinal epithelial chemokine (C-C motif) ligand 7 (CCL7) plays an important role in the development of toxin-induced acute liver damage. The detailed effects of intestinal epithelial CCL7 on chronic diseases; however, are still unclear. Here, we aimed to investigate the impact of intestinal epithelial CCL7 overexpression on high-fat diet (HFD)-induced obesity and steatohepatitis in mice.

Methods

Intestinal epithelial CCL7 overexpression (CCL7^tgIEC) mice and their wild-type (WT) littermates were fed with normal chow or HFD for 16 weeks to induce obesity and non-alcoholic fatty liver disease. Body weight gain, as well as adipose tissue index were assessed. Liver injury was monitored by histological analysis and real time polymerase chain reaction. Gut microbial composition was analyzed by 16S rRNA gene sequencing.

Results

We found that the CCL7^tgIEC mice on a HFD had markedly decreased weight gain (8.9 vs. 17.0 g, P < 0.05) and a lower adipose tissue index that include mesenteric fat (1.0% vs. 1.76%, P < 0.05), gonadal fat (2.1% vs. 6.1%, P < 0.05), subcutaneous fat (1.0% vs. 2.8%, P < 0.05) compared to WT animals. HFD-induced glucose intolerance and insulin resistance were also significantly improved in CCL7^tgIEC mice compared to WT. Furthermore, HFD-fed CCL7^tgIEC mice displayed less hepatic lipid accumulation and lower expression of inflammatory factors than WT mice. 16S rRNA gene sequencing demonstrated that CCL7 overexpression in intestinal epithelial cells improved HFD-induced gut microbial dysbiosis.

Conclusions

Our study revealed that CCL7 overexpression in the intestinal epithelium protects mice against the progression of diet-induced obesity, hepatic steatosis, and enteric dysbiosis.

SOX18 promotes gastric cancer metastasis through transactivating MCAM and CCL7

The therapeutic strategies for advanced gastric cancer (GC) remain unsatisfying and limited. Therefore, it is still imperative to fully elucidate the mechanisms underlying GC metastasis. Here, we report a novel role of SRY-box transcription factor 18 (SOX18), a member of the SOX family, in promoting GC metastasis. The elevated expression of SOX18 was positively correlated with distant metastasis, higher AJCC stage, and poor prognosis in human GC. SOX18 expression was an independent and significant risk factor for the recurrence and survival in GC patients. Up-regulation of SOX18 promoted GC invasion and metastasis, whereas down-regulation of SOX18 decreased GC invasion and metastasis. Melanoma cell adhesion molecule (MCAM) and C-C motif chemokine ligand 7 (CCL7) are direct transcriptional targets of SOX18. Knockdown of MCAM and CCL7 significantly decreased SOX18-mediated GC invasion and metastasis, while the stable overexpression of MCAM and CCL7 reversed the decrease in cell invasion and metastasis that was induced by the inhibition of SOX18. A mechanistic investigation indicated that the upregulation of SOX18 that was mediated by the CCL7-CCR1 pathway relied on the ERK/ELK1 pathway. SOX18 knockdown significantly reduced CCL7-enhanced GC invasion and metastasis. Furthermore, BX471, a specific CCR1 inhibitor, significantly reduced the SOX18-mediated GC invasion and metastasis. In human GC tissues, SOX18 expression was positively correlated with CCL7 and MCAM expression, and patients with positive coexpression of SOX18/CCL7 or SOX18/MCAM had the worst prognosis. In conclusion, we defined a CCL7-CCR1-SOX18 positive feedback loop that played a pivotal role in GC metastasis, and targeting this pathway may be a promising therapeutic option for the clinical management of GC.

Tumor progression locus 2 (TPL2) in tumor-promoting Inflammation, Tumorigenesis and Tumor Immunity

Over the years, tumor progression locus 2 (TPL2) has been identified as an essential modulator of immune responses that conveys inflammatory signals to downstream effectors, subsequently modulating the generation and function of inflammatory cells. TPL2 is also differentially expressed and activated in several cancers, where it is associated with increased inflammation, malignant transformation, angiogenesis, metastasis, poor prognosis and therapy resistance. However, the relationship between TPL2-driven inflammation, tumorigenesis and tumor immunity has not been addressed. Here, we reconcile the function of TPL2-driven inflammation to oncogenic functions such as inflammation, proliferation, apoptosis resistance, angiogenesis, metastasis, immunosuppression and immune evasion. We also address the controversies reported on TPL2 function in tumor-promoting inflammation and tumorigenesis, and highlight the potential role of the TPL2 adaptor function in regulating the mechanisms leading to pro-tumorigenic inflammation and tumor progression. We discuss the therapeutic implications and limitations of targeting TPL2 for cancer treatment. The ideas presented here provide some new insight into cancer pathophysiology that might contribute to the development of more integrative and specific anti-inflammatory and anti-cancer therapeutics.

Toxicity of TiO2 Nanoparticles: Validation of Alternative Models

There are many studies concerning titanium dioxide (TiO₂) nanoparticles (NP) toxicity. Nevertheless, there are few publications comparing in vitro and in vivo exposure, and even less comparing air–liquid interface exposure (ALI) with other in vitro and in vivo exposures. The identification and validation of common markers under different exposure conditions are relevant for the development of smart and quick nanotoxicity tests. In this work, cell viability was assessed in vitro by WST-1 and LDH assays after the exposure of NR8383 cells to TiO₂ NP sample. To evaluate in vitro gene expression profile, NR8383 cells were exposed to TiO₂ NP during 4 h at 3 cm² of TiO₂ NP/cm² of cells or 19 μg/mL, in two settings—submerged cultures and ALI. For the in vivo study, Fischer 344 rats were exposed by inhalation to a nanostructured aerosol at a concentration of 10 mg/m³, 6 h/day, 5 days/week for 4 weeks. This was followed immediately by gene expression analysis. The results showed a low cytotoxic potential of TiO₂ NP on NR8383 cells. Despite the absence of toxicity at the doses studied, the different exposures to TiO₂ NP induce 18 common differentially expressed genes (DEG) which are involved in mitosis regulation, cell proliferation and apoptosis and inflammation transport of membrane proteins. Among these genes, we noticed the upregulation of Ccl4, Osm, Ccl7 and Bcl3 genes which could be suggested as early response biomarkers after exposure to TiO₂ NP. On the other hand, the comparison of the three models helped us to validate the alternative ones, namely submerged and ALI approaches.

Recent advances in understanding cancer-associated fibroblasts in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) is a devastating disease with a poor survival rate. It is resistant to therapy in part due to its unique tumor microenvironment, characterized by a desmoplastic reaction resulting in a dense stroma that constitutes a large fraction of the tumor volume. A major contributor to the desmoplastic reaction are cancer-associated fibroblasts (CAFs). CAFs actively interact with cancer cells and promote tumor progression by different mechanisms, including extracellular matrix deposition, remodeling, and secretion of tumor promoting factors, making CAFs an attractive target for PDA. However, emerging evidences indicate significant tumor-suppressive functions of CAFs, highlighting the complexity of CAF biology. CAFs were once considered as a uniform cell type within the cancer stroma. Recently, the existence of CAF heterogeneity in PDA has become appreciated. Due to advances in single cell technology, distinct subtypes of CAFs have been identified in PDA. Here we review recent updates in CAF biology in PDA, which may help develop effective CAF-targeted therapies in the future.

Anti-HER2 induced myeloid cell alterations correspond with increasing vascular maturation in a murine model of HER2+ breast cancer

BACKGROUND

Therapy targeted to the human epidermal growth factor receptor type 2 (HER2) is used in combination with cytotoxic therapy in treatment of HER2+ breast cancer. Trastuzumab, a monoclonal antibody that targets HER2, has been shown pre-clinically to induce vascular changes that can increase delivery of chemotherapy. To quantify the role of immune modulation in treatment-induced vascular changes, this study identifies temporal changes in myeloid cell infiltration with corresponding vascular alterations in a preclinical model of HER2+ breast cancer following trastuzumab treatment.

METHODS

HER2+ tumor-bearing mice (N = 46) were treated with trastuzumab or saline. After extraction, half of each tumor was analyzed by immunophenotyping using flow cytometry. The other half was quantified by immunohistochemistry to characterize macrophage infiltration (F4/80), vascularity (CD31 and α-SMA), proliferation (Ki67) and cellularity (H&E). Additional mice (N = 10) were used to quantify differences in tumor cytokines between control and treated groups.

RESULTS

Immunophenotyping showed an increase in macrophage infiltration 24 h after trastuzumab treatment (P ≤ 0.05). With continued trastuzumab treatment, the M1 macrophage population increased (P = 0.02). Increases in vessel maturation index (i.e., the ratio of α-SMA to CD31) positively correlated with increases in tumor infiltrating M1 macrophages (R = 0.33, P = 0.04). Decreases in VEGF-A and increases in inflammatory cytokines (TNF-α, IL-1β, CCL21, CCL7, and CXCL10) were observed with continued trastuzumab treatment (P ≤ 0.05).

CONCLUSIONS

Preliminary results from this study in a murine model of HER2+ breast cancer show correlations between immune modulation and vascular changes, and reveals the potential for anti-HER2 therapy to reprogram immunosuppressive components of the tumor microenvironment. The quantification of immune modulation in HER2+ breast cancer, as well as the mechanistic insight of vascular alterations after anti-HER2 treatment, represent novel contributions and warrant further assessment for potential clinical translation.

The chemokine CCL7 regulates invadopodia maturation and MMP-9 mediated collagen degradation in liver-metastatic carcinoma cells

Liver metastases remain a major cause of death from gastrointestinal tract cancers and other malignancies, such as breast and lung carcinomas. Understanding the underlying biology is essential for the design of effective therapies. We previously identified the chemokine CCL7 and its receptor CCR3 as critical mediators of invasion and metastasis in lung and colon carcinoma cells. Here we show that the CCL7/CCR3 axis regulates a late stage in invadopodia genesis namely, the targeting of MMP-9 to the invadopodia complex, thereby promoting invadopodia maturation and collagen degradation. We show that this process could be blocked by overexpression of a dominant negative RhoA in highly invasive cells, while a constitutively active RhoA upregulated invadopodia maturation in CCL7-silenced and poorly invasive and metastatic cells and also enhanced their metastatic potential in vivo, collectively, implicating RhoA activation in signaling downstream of CCL7. Blockade of the ERK or PI3K pathways by chemical inhibitors also inhibited invadopodia formation, but affected the initiation stage of invadopodia genesis. Our data implicate CCL7/CCR3 signaling in invadopodia maturation and suggest that chemokine signaling acts in concert with extracellular matrix-initiated signals to promote invasion and liver metastasis.

Triple-Negative Primary Breast Tumors Induce Supportive Premetastatic Changes in the Extracellular Matrix and Soluble Components of the Lung Microenvironment

The lung is one of the deadliest sites of breast cancer metastasis, particularly in patients with triple-negative (TN) disease. We hypothesized that the presence of a TN primary breast tumor induces changes in the extracellular matrix (ECM) and soluble components of the lung microenvironment that support metastatic behavior. SUM159 (TN) and MCF7 (luminal A) breast cancer cells were injected into mice, and primary breast tumors were established prior to assessing metastatic niche changes. We observed increased CD117⁺ hematopoietic progenitor cells in the bone marrow of SUM159 mice versus MCF7 or control mice (p < 0.05). Relative to mice bearing MCF7 tumors and non-tumor controls, mice bearing SUM159 tumors demonstrated enhanced expression of ECM proteins in the lung (fibronectin, tenascin-c and periostin), with similar changes observed in lung fibroblasts treated with extracellular vesicles (EVs) from TN breast cancer cells (p < 0.05). Exposure to lung-conditioned media (LCM) from SUM159 tumor-bearing mice resulted in increased migration/proliferation of both SUM159 and MCF7 cells relative to the control (p < 0.05). In contrast, LCM from MCF-7 tumor-bearing mice had no such effect. LCM from SUM159 tumor-bearing mice contained 16 unique proteins relative to other LCM conditions, including the metastasis-associated proteins CCL7, FGFR4, GM-CSF, MMP3, thrombospondin-1 and VEGF. These findings suggest for the first time that the TN breast cancer molecular subtype may be an important determinant of premetastatic changes to both the ECM and soluble components of the lung, potentially mediated via breast cancer-derived EVs.

CCL7 Signaling in the Tumor Microenvironment

The tumor microenvironment is the primary location in which tumor cells and the host immune system interact. There are many physiological, biochemical, cellular mechanisms in the neighbor of tumor which is composed of various cell types. Interactions of chemokines and chemokine receptors can recruit immune cell subsets into the tumor microenvironment. These interactions can modulate tumor progression and metastasis. In this chapter, we will focus on chemokine (C-C motif) ligand 7 (CCL7) that is highly expressed in the tumor microenvironment of various cancers, including colorectal cancer, breast cancer, oral cancer, renal cancer, and gastric cancer. We reviewed how CCL7 can affect cancer immunity and tumorigenesis by describing its regulation and roles in immune cell recruitment and stromal cell biology.

The Composition of Surgical Wound Fluids from Breast Cancer Patients is Affected by Intraoperative Radiotherapy Treatment and Depends on the Molecular Subtype of Breast Cancer

Invasive oncological procedures affect the remaining tumor cells by increasing their survival, proliferation, and migration through the induction of wound healing response. The phenomena of local relapse after breast-conserving surgery (BCS) has resulted in a series of research and clinical trials with the aim of assessing whether localized intraoperative radiotherapy (IORT), may be beneficial in inhibiting local recurrences. Therefore, it is essential to assess the impact of intraoperative radiotherapy in modulating the immunological response and wound healing process. Thus, we decided to perform a quantitative analysis of the composition of surgical wound fluids (SWF) in two groups of breast cancer (BC) patients: those treated with BCS followed by IORT, and those who underwent BCS alone. We found that several cytokines, which are believed to have anti-tumor properties, were highly expressed in the luminal A breast cancer subtype in the IORT treatment group. Interestingly, we also found significant differences between IORT patients with tumors of different molecular subtypes. Based on these findings, we hypothesized that IORT treatment might be beneficial in changing the tumor bed microenvironment, making it less favorable for tumor recurrence due to decreased concentration of tumor-facilitating cytokines, especially in the luminal A subtype of BC.

Irisin promotes C2C12 myoblast proliferation via ERK-dependent CCL7 upregulation

Irisin is an exercise-induced myokine that has various physiological functions, such as roles in energy expenditure, glucose/lipid metabolism, and muscle development. In muscle development, myoblast proliferation is known to be a first step, and recent studies have reported that an increased irisin level is involved in the promotion of cell proliferation in various cell types, including myoblasts. However, the exact mechanism of action by which irisin promotes myoblast proliferation has not been reported. In this study, we aimed to determine the pro-proliferative effect of irisin on C2C12 myoblasts and its mechanism of action. Irisin induced C2C12 cell proliferation and upregulated the mRNA levels of markers of proliferation Pcna, Mki67, and Mcm2. Irisin increased extracellular signal-regulated kinase (ERK) phosphorylation, and U0126, an ERK pathway inhibitor, suppressed irisin-induced C2C12 cell proliferation. Transcriptomic and qRT-PCR analysis showed that Ccl2, Ccl7, Ccl8, and C3 are potential downstream regulators of ERK signaling that promote C2C12 cell proliferation. Knockdown of Ccl7 revealed that irisin upregulates chemokine (C-C motif) ligand 7 (CCL7) and subsequently promotes C2C12 cell proliferation. These results suggest that irisin promotes C2C12 myoblast proliferation via ERK-dependent CCL7 upregulation and may aid in understanding how irisin contributes to muscle development.

Generation of monocyte-derived tumor-associated macrophages using tumor-conditioned media provides a novel method to study tumor-associated macrophages in vitro

Background

Tumor-associated macrophages (TAM) are expanded and exhibit tumor-promoting properties within the tumor microenvironment. Current methods to study TAM have not been replicated across cancer types and often do not include exogenous growth factors from the tumor, a key factor in TAM differentiation in vivo.

Methods

In this study, an in vitro method to generate monocyte- derived TAM using tumor- conditioned media (TCM) and a cytokine cocktail containing IL-4, IL-10, and M-CSF was utilized to study the phenotype, morphology, and function of TAM across multiple cancer types. TCM was generated from two breast cancer cell lines and an Epstein-Barr virus-positive lymphoma cell line. The properties of in vitro generated TAM were compared to in vitro generated M1 and M2- like macrophages and TAM isolated from patients with cancer.

Results

TAM generated in this fashion displayed an increase in CD163/CD206 co-expression compared to M2- like macrophages (87 and 36%, respectively). TAM generated in vitro exhibited increased transcript levels of the functional markers IL-6, IL-10, CCL2, c-Myc, iNOS, and arginase compared to in vitro generated M2-like macrophages. Functionally, in vitro generated TAM inhibited the proliferation of T cells (47% decrease from M1-like macrophages) and the production of IFN-γ by natural killer cells was inhibited (44%) when co-cultured with TAM. Furthermore, in vitro generated TAM secreted soluble factors that promote the growth and survival of tumor cells.

Conclusions

Limited access to patient TAM highlights the need for methods to generate TAM in vitro. Our data confirm that monocyte-derived TAM can be generated reliably using TCM plus the cytokine cocktail of IL-4, IL-10, and M-CSF. Given the ability of TAM to inhibit immune cell function, continued study of methods to deplete or deactivate TAM in the setting of cancer are warranted.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0622-0) contains supplementary material, which is available to authorized users.

Torque-Teno virus viral load as a potential endogenous marker of immune function in solid organ transplantation

Solid organ transplantation (SOT) recipients receive immunosuppressive therapy to avoid rejection of the transplanted organ. Immunosuppressive therapy increases the risk of infections. However, no existing marker reliably reveals the status of the immune function in SOT recipients. Torque-Teno virus or Transfusion-transmitted virus (TTV) has gained attention as a possible endogenous marker of the immune function. TTV is a non-enveloped, circular single strand DNA virus, and it may be considered a part of the human virome. In a bidirectional relationship, the immune system detects TTV and TTV may also modulate the activity of immune system. These characteristics have made the virus a possible candidate indicator of immune function. In this systematic review, we describe the role and potential function of TTV viral load as an endogenous marker of the immune function and consequently the level of immune suppression in SOT recipients.

CC chemokines are differentially expressed in Breast Cancer and are associated with disparity in overall survival

Despite recent advances, breast cancer (BrCa) still affects many women and the impact is disproportional in African Americans (AA) compared to European Americans (EA). Addressing socioeconomic and behavioral status has not been enough to reduce disparity, suggesting contribution of biological differences in BrCa disparity. Our laboratory was first to show involvement of CC chemokines in BrCa. In this study, using ONCOMINE, TCGA, bc-GenExMiner and KMplotter, we examined the association of CC chemokines in BrCa outcomes and disparity. We show over-expression of CCL5, -7, -11, -17, -20, -22 and -25 in BrCa tissues. High mRNA levels of CCL7, -8, -17, -20 and -25 predicted a decrease in overall survival (OS). CCL7 and CCL8 were associated with decreased relapse-free survival. Expression of CCL17 and CCL25 was associated with decreased OS in AA. In EA, CCL8 was associated with decreased OS. Expression of CCL5, -7, -8, -17, -20 and -25 was highest in TNBC. Expression of CCL11 and CCL22 was associated with HER2. CCL7, -8, -17, -20 and -25 were elevated in AAs. In conclusion, our analysis suggests significant association of CC-chemokines in BrCa progression, OS and disparate disease outcome in AA compared to EA patients.

Ubiquitous and cell type-specific transcriptomic changes triggered by dissipation of monovalent cation gradients in rodent cells: Physiological and pathophysiological implications

Elevation of [Na⁺]_i/[K⁺]_i-ratio is considered as one of the major signals triggering transcriptomic changes in various cells types. In this study, we identified ubiquitous and cell type-specific [Formula: see text] -sensitive genes by comparative analysis of transcriptomic changes in ouabain-treated rat aorta smooth muscle cells and rat aorta endothelial cells (RASMC and RAEC, respectively), rat cerebellar granule cells (RCGC), and mouse C2C12 myoblasts. Exposure of the cells to ouabain increased intracellular Na⁺ content by ~14, 8, 7, and 6-fold and resulted in appearance of 7577, 2698, 2120, and 1146 differentially expressed transcripts in RAEC, RASMC, C2C12, and RCGC, respectively. Eighty-three genes were found as the intersection of the four sets of identified transcripts corresponding to each cell type and are classified as ubiquitous. Among the 10 top upregulated ubiquitous transcripts are the following: Dusp6, Plk3, Trib1, Ccl7, Mafk, Atf3, Ptgs2, Cxcl1, Spry4, and Coq10b. Unique transcripts whose expression is cell-specific include 4897, 1523, 789, and 494 transcripts for RAEC, RASMC, C2C12, and RCGC, respectively. The role of gene expression and signal pathways induced by dissipation of transmembrane gradient of monovalent cations in the development of various diseases is discussed with special attention to cardiovascular and pulmonary illnesses.