Inflammation Mediates the Development of Aggressive Breast Cancer Following Radiotherapy

Impact of preoperative white blood cell count on outcomes in different stage colorectal cancer patients undergoing surgical resection: a single-institution retrospective cohort study

PURPOSE

To explore the association between preoperative WBC count and the long-term survival outcomes and clinical outcomes in different stage patients who underwent surgical resection for colorectal cancer (CRC).

PATIENTS AND METHODS

A cohort of 8121 Chinese patients who underwent surgical resection for CRC from January 1, 2008 to December 31, 2014 were enrolled as part of the retrospective cohort were retrospectively analyzed. Based on that the preoperative WBC optimal cut-off value was 7*109/L (7,000/µL), the high preoperative WBC group and the low preoperative WBC group was defined. Inverse probability of treatment weighting (IPTW) using the propensity score was used to reduce confounding. The impact of preoperative WBC count on overall survival (OS) and disease-free survival (DFS) was investigated using the Kaplan-Meier method and Univariate Cox proportional hazards models in different stage subgroup respectively.

RESULTS

After IPTW, the clinical characters in the high preoperative WBC count group and the low preoperative WBC count group were balanced. Kaplan-Meier analysis showed that the 5-year OS rate were significantly lower in the high preoperative WBC count group overall, in stage II and IV. The 5-year DFS rate was significantly lower overall, in stage II and III in the high preoperative WBC count group. High preoperative WBC count was associated with poorer OS overall in stage II and stage IV.

CONCLUSIONS

This study suggests that preoperative WBC count is an independent risk factor for survival in patients undergoing colorectal surgery and may need to consider the stage of cancer when applied to predict long-term adverse outcome prognosis.

The relationship between nonsteroidal anti-inflammatory drugs and cancer incidence: An umbrella review

Several clinical and preclinical studies have shown that nonsteroidal anti-inflammatory drugs (NSAIDs), particularly aspirin, reduce the incidence of various cancer types. However, there is still a lack of literature evaluating the overall association between multiple cancer morbidities and NSAIDs. Thus, we conducted an umbrella review to evaluate the quality of evidence, validity, and biases of the existing systematic reviews and meta-analyses on the relationships between NSAIDS and multiple tumor incidence outcomes. We found that NSAIDs might be associated with a decreased risk of several cancers, including the central nervous system, breast, esophageal, gastric, head and neck, hepatocellular, cholangiocarcinoma, colorectal, endometrial, lung, ovary, prostate, and pancreatic cancers, but regular intake of any dose of non-aspirin NSAIDs (NA-NSAIDs) could increase the incidence of kidney cancer. However, most of included studies are evaluated as low quality according to our evidence assessment. Furthermore, due to the potential side effects, such as hemorrhage, digestive symptoms and peptic ulcer, it is still not recommend to use NSAIDs regularly to prevent cancers.

Monitoring TGFβ signaling in irradiated tumors

Transforming growth factor β (TGFβ) is exquisitely regulated under physiological conditions but its activity is highly dysregulated in cancer. All cells make TGFβ and have receptors for the ligand, which is sequestered in the extracellular matrix in a latent form. Ionizing radiation elicits rapid release of TGFβ from these stores, so-called activation, over a wide range of doses and exposures, including low dose (<1Gy) whole-body irradiation, creating an extraordinarily potent signal in the irradiated tissue or tumor. Hence, accurate evaluation of TGFβ activity is complicated because of its ubiquitous distribution as a latent complex. Here we describe conditions for assays that reveal TGFβ activity in situ using either tissue preparations or functional imaging.

Local radiotherapy for murine breast cancer increases risk of metastasis by promoting the recruitment of M-MDSCs in lung

BACKGROUND

Radiotherapy is one of the effective methods for treatment of breast cancer; however, controversies still exist with respect to radiotherapy for patients with TNBC. Here, we intend to explore the mechanism by which local radiotherapy promotes the recruitment of M-MDSCs in the lung and increases the risk of lung metastasis in TNBC tumor-bearing mice.

METHODS

A single dose of 20 Gy X-ray was used to locally irradiate the primary tumor of 4T1 tumor-bearing mice. Tumor growth, the number of pulmonary metastatic nodules, and the frequency of MDSCs were monitored in the mice. Antibody microarray and ELISA methods were used to analyze the cytokines in exosomes released by irradiated (IR) or non-IR 4T1 cells. The effects of the exosomes on recruitment of MDSCs and colonization of 4T1 cells in the lung of normal BALB/c mice were observed with the methods of FCM and pathological section staining. T lymphocytes or 4T1 cells co-cultured with MDSCs were performed to demonstrate the inhibitory effect on T lymphocytes or accelerative migration effect on 4T1 cells. Finally, a series of in vitro experiments demonstrated how the exosomes promote the recruitment of M-MDSCs in lung of mice.

RESULTS

Even though radiotherapy reduced the burden of primary tumors and larger lung metastatic nodules (≥ 0.4 mm²), the number of smaller metastases (< 0.4 mm²) significantly increased. Consistently, radiotherapy markedly potentiated M-MDSCs and decreased PMN-MDSCs recruitment to lung of tumor-bearing mice. Moreover, the frequency of M-MDSCs of lung was positively correlated with the number of lung metastatic nodules. Further, M-MDSCs markedly inhibited T cell function, while there was no difference between M-MDSCs and PMN-MDSCs in promoting 4T1 cell migration. X-ray irradiation promoted the release of G-CSF, GM-CSF and CXCl1-rich exosomes, and facilitated the migration of M-MDSCs and PMN-MDSCs into the lung through CXCL1/CXCR2 signaling. While irradiated mouse lung extracts or ir/4T1-exo treated macrophage culture medium showed obvious selective chemotaxis to M-MDSCs. Mechanistically, ir/4T1-exo induce macrophage to produce GM-CSF, which further promoted CCL2 release in an autocrine manner to recruit M-MDSCs via CCL2/CCR2 axis.

CONCLUSIONS

Our work has identified an undesired effect of radiotherapy that may promote immunosuppressive premetastatic niches formation by recruiting M-MDSCs to lung. Further studies on radiotherapy combined CXCR2 or CCR2 signals inhibitors were necessary.

Targeting cancer-related inflammation with non-steroidal anti-inflammatory drugs: Perspectives in pharmacogenomics

Inflammatory processes are essential for innate immunity and contribute to carcinogenesis in various malignancies, such as colorectal cancer, esophageal cancer and lung cancer. Pharmacotherapies targeting inflammation have the potential to reduce the risk of carcinogenesis and improve therapeutic efficacy of existing anti-cancer treatment. Non-steroidal anti-inflammatory drugs (NSAIDs), comprising a variety of structurally different chemicals that can inhibit cyclooxygenase (COX) enzymes and other COX-independent pathways, are originally used to treat inflammatory diseases, but their preventive and therapeutic potential for cancers have also attracted researchers' attention. Pharmacogenomic variability, including distinct genetic characteristics among different patients, can significantly affect pharmacokinetics and effectiveness of NSAIDs, which might determine the preventive or therapeutic success for cancer patients. Hence, a more comprehensive understanding in pharmacogenomic characteristics of NSAIDs and cancer-related inflammation would provide new insights into this appealing strategy. In this review, the up-to-date advances in clinical and experimental researches targeting cancer-related inflammation with NSAIDs are presented, and the potential of pharmacogenomics are discussed as well.

DOSE-RATE EFFECT OF RADIATION ON RAT MAMMARY CARCINOGENESIS AND AN EMERGING ROLE FOR STEM CELL BIOLOGY

The uncertain cancer risk of protracted radiation exposure at low dose rates is an important issue in radiological protection. Tissue stem/progenitor cells are a supposed origin of cancer and may contribute to the dose-rate effect on carcinogenesis. The authors have shown that female rats subjected to continuous whole body γ irradiation as juveniles or young adults have a notably reduced incidence of mammary cancer as compared with those irradiated acutely. Experiments using the mammosphere formation assay suggested the presence of radioresistant progenitor cells. Cell sorting indicated that basal progenitor cells in rat mammary gland were more resistant than luminal progenitors to killing by acute radiation, especially at high doses. Thus, the evidence indicates a cell-type-dependent inactivation of mammary cells that manifests only at high acute doses, implying a link to the observed dose-rate effect on carcinogenesis.

Innovative targets of the lncRNA-miR-mRNA network in response to low-dose aspirin in breast cancer patients

This study aimed to investigate innovative targets in breast cancer patients by considering the interaction of the lncRNA-miR-mRNA network in response to low-dose aspirin. The candidate miRs were first taken from the GEO and TCGA databases. Then, the candidate network was constructed using the high-throughput sequencing data. The expression levels of candidate targets were finally measured using Real-Time PCR in luminal A breast cancer patients undergoing aspirin (80 mg daily for three months) and non-aspirin groups during chemotherapy after surgery. The expression levels of TGFβ, IL-17, IFNγ, and IL-β proteins were measured using the ELISA technique. 5 lncRNAs, 12 miRs, and 10 genes were obtained in the bioinformatic phase. A significant expression increase of the candidate tumor suppressor lncRNAs, miRs, and genes and a substantial expression decrease of the candidate onco-lncRNAs, oncomiRs, and oncogenes were achieved after the aspirin consumption. Unlike the non-aspirin group, the expression levels of TGFβ, IL-17, IFNγ, and IL-β proteins were significantly decreased following aspirin consumption. The Kaplan-Meier analysis indicated a longer overall survival rate in the patients after aspirin consumption. Our results showed that the lncRNA-miR-mRNA network might be a significant target for aspirin; their expression changes may be a new strategy with potential efficacy for cancer therapy or prevention.

Tumor ENPP1(CD203a)/Haptoglobin Axis Exploits Myeloid-Derived Suppressor Cells to Promote Post-Radiotherapy Local Recurrence in Breast Cancer

Locoregional failure (LRF) in breast cancer patients post-surgery and post-irradiation (IR) is linked to a dismal prognosis. In a refined new model, we identified Enpp1 (Ectonucleotide pyrophosphatase /phosphodiesterase 1/CD203a) to be closely associated with LRF. Enpp1high circulating tumor cells (CTC) contribute to relapse by a self-seeding mechanism. This process requires the infiltration of PMN-MDSC and neutrophil extracellular traps (NET) formation. Genetic and pharmacological Enpp1 inhibition or NET blockade extend relapse-free survival. Furthermore, in combination with fractionated irradiation (FD), Enpp1 abrogation obliterates LRF. Mechanistically, Enpp1-generated adenosinergic metabolites enhance Haptoglobin (Hp) expression. This inflammatory mediator elicits myeloid invasiveness and promotes NET formation. Accordingly, a significant increase in ENPP1 and NET formation is detected in relapsed human breast cancer tumors. Moreover, high ENPP1 or HP levels are associated with poor prognosis. These findings unveil the ENPP1/HP axis as an unanticipated mechanism exploited by tumor cells linking inflammation to immune remodeling favoring local relapse.

Clair D, Li JD, Xu R. RORα Suppresses Cancer-Associated Inflammation by Repressing Respiratory Complex I-Dependent ROS Generation

Breast cancer development is associated with macrophage infiltration and differentiation in the tumor microenvironment. Our previous study highlights the crucial function of reactive oxygen species (ROS) in enhancing macrophage infiltration during the disruption of mammary tissue polarity. However, the regulation of ROS and ROS-associated macrophage infiltration in breast cancer has not been fully determined. Previous studies identified retinoid orphan nuclear receptor alpha (RORα) as a potential tumor suppressor in human breast cancer. In the present study, we showed that retinoid orphan nuclear receptor alpha (RORα) significantly decreased ROS levels and inhibited ROS-mediated cytokine expression in breast cancer cells. RORα expression in mammary epithelial cells inhibited macrophage infiltration by repressing ROS generation in the co-culture assay. Using gene co-expression and chromatin immunoprecipitation (ChIP) analyses, we identified complex I subunits NDUFS6 and NDUFA11 as RORα targets that mediated its function in suppressing superoxide generation in mitochondria. Notably, the expression of RORα in 4T1 cells significantly inhibited cancer metastasis, reduced macrophage accumulation, and enhanced M1-like macrophage differentiation in tumor tissue. In addition, reduced RORα expression in breast cancer tissue was associated with an increased incidence of cancer metastasis. These results provide additional insights into cancer-associated inflammation, and identify RORα as a potential target to suppress ROS-induced mammary tumor progression.