Grape-seed polyphenols inhibit AAA in mice via regulation of macrophage polarization

AIM

Abdominal aortic aneurysm (AAA) is characterized by macrophage polarization, and at present, no drug therapy is available. Although grape-seed polyphenols (GSP) showed an anti-AAA effect, the role of GSP in the phenotype shift in macrophages remains unknown.

METHOD

The main phenolic compounds in GSP were determined by LC-MS. Male C57BL/6 mice were divided into four equal groups, namely sham group, CaPO4 group, CaPO4+GSP low-dose group, and CaPO4+GSP high-dose group. GSP was administered intragastrically after CaPO4 application. Molecular expressions were histologically evaluated and analyzed by various staining assays and FACS.

RESULTS

GSP administration inhibited CaPO4-induced AAA formation, which correlated with a decrease in macrophage infiltration and retainment of vascular smooth muscle layer as compared to those in the CaPO4 group. FACS assay showed that the GSP administration dose-dependently decreased the CD54 expression (low-dose group: 11.4 ± 2.1 % and high-dose group: 4.8 ± 1.4 % vs 23.2 ± 3.6 %; p < 0.05 and p < 0.01, respectively) and increased the CD206 expression of F4/80-positive cells in GSP-administered groups as compared with that in CaPO4-injured aortas in the CaPO4 group (low-dose group: 22.4 ± 3.3 % and high-dose group: 26.7 ± 4.2 % vs 8.1 ± 1.3 %; p < 0.05 and p < 0.01, respectively).

CONCLUSIONS

GSP could be a pharmacologically potent agent in the treatment of AAA (Tab. 1, Fig. 3,Ref. 20). Text in PDF www.elis.sk Keywords: grape-seed polyphenols, abdominal aortic aneurysm, macrophage, inflammatory, polarization.

Immunorelated gene polymorphisms associated with acute myeloid leukemia

Although the pathogenesis of acute myeloid leukemia (AML) is still unknown, accumulating evidence has revealed that immune response plays a vital part in the pathogenesis. Here, we investigated the involvement of 21 single nucleotide polymorphisms (SNPs) of immunorelated genes, including cytokines [interleukin (IL)-2, IL-4, IL-9, IL-12A, IL-22, interferon (IFN-α) and transforming growth factor (TGF)-β1], transcriptional regulatory genes (TBX21, STAT1, STAT3, STAT5B, STAT6, GATA3, FOXP3 and IRF4) and others (IL2RA, IL6R, NFKBIA) in 269 AML in-patients and 200 healthy controls. Furthermore, we analyzed the relationship between the SNPs and clinical characteristics. Immunorelated SNP genotyping was performed on the Sequenom MassARRAY iPLEX platform. All the SNPs in healthy controls were consistent with Hardy-Weinberg equilibrium. All final P-values were adjusted by Bonferroni multiple testing. Our results showed that IL-22 (rs2227491) was significantly associated with the white blood cell (WBC) counts. Signal transducer and activator of transcription 5B (STAT-5B) (rs6503691) showed a close relationship with the recurrent genetic abnormalities in patients with AML. We verified the negatively independent effect of age and risk of cytogenetics on overall survival (OS). More importantly, the GG genotype of IL-12A (rs6887695) showed a negative impact on AML prognosis independently. Furthermore, the relative expression of IL-12 was decreased in GG genotype, no matter under a co-dominant or recessive model. However, no correlation was observed between the SNPs mentioned above and disease susceptibility, risk stratification and survival. Our findings suggest that immunorelated gene polymorphisms are associated with prognosis in AML, which may perform as novel inspection targets for AML patients.

Formation and Development of Environmental Forensics System in China

With the growing attention on ecological environment problems and gradual realization of ecological environment value, environmental damage has jumped from administrative penalty to a new stage, judicial penalty, and environmental damage appraisal has provided a legal weapon to safeguard ecological security. As a new forensic category of China with high comprehensiveness and technical difficulty, environmental damage appraisal involves diversified and complex subjects, fields and appraisal objects, and is still in an early stage in terms of theory and practice. This study aims to provide an important reference for the improvement of the Chinese environmental damage appraisal system of environmental damage by summarizing advanced international experience in areas such as laws and regulations, working mechanism and technical system, and putting forward targeted countermeasures and suggestions based on the problems existing in the development and practice of environmental damage appraisal in China.

Long-term follow-up of owned, free-roaming dogs in South Africa naturally exposed to Babesia rossi

Babesia rossi is an important, tick-borne intraerythrocytic protozoan parasite; however, its natural history and epidemiology is poorly understood. Babesia rossi is the most virulent Babesia sp. in domestic dogs and is generally considered to cause severe babesiosis, which is fatal if left untreated. However, subclinical infections and mild disease from B. rossi have been reported, although the clinical progression of these cases was not reported. Therefore, to better understand B. rossi under field conditions, we evaluated its clinical progression and seroprevalence in an owned, free-roaming dog population in Zenzele, South Africa, where the parasite is endemic and prevention is not routine. The entire dog population in Zenzele was monitored intensively at the individual level from March 2008 until April 2014, primarily for a longitudinal study on rabies control. Subsequent evaluation of B. rossi comprised analyses of clinical and laboratory data collected from the Zenzele dog population during the 6 year study period. A substantial proportion (31% (n = 34)) of 109 dogs (randomly selected from every available dog in February/March 2010 older than ~6-8 weeks (n = 246)) tested by Indirect Fluorescent Antibody Test had seroconverted strongly to B. rossi. All 34 dogs were generally consistently healthy adults, determined from regular clinical examinations between March 2008 and April 2014. Blood smear examinations at multiple time points between July 2009 and February 2011 were also undertaken for almost all of these (34) seropositive dogs and all those tested were consistently negative for Babesia spp. Subclinical infections and mild disease were also the main findings for a separate group of 18 dogs positive for Babesia spp. on blood smear examination and confirmed to be infected with B. rossi by Polymerase Chain Reaction - Reverse Line Blot. Almost all of these dogs were positive at only one time point from repeat blood smear examinations between July 2009 and February 2011. We suggest that these observations are consistent with immunity acquired from repeated, low-level exposure to the parasite, generating transient subclinical infections or mild disease. Should this be the case, the use of tick control, particularly in adult dogs in free-roaming populations in B. rossi endemic regions, should be carefully considered.

Randomized clinical trial of intraoperative dexmedetomidine to prevent delirium in the elderly undergoing major non-cardiac surgery

Background

Delirium is common in elderly patients after surgery and is associated with poor outcomes. This study aimed to investigate the impact of intraoperative dexmedetomidine on the incidence of delirium in elderly patients undergoing major surgery.

Methods

This was a randomized double-blind placebo-controlled trial. Elderly patients (aged 60 years or more) scheduled to undergo major non-cardiac surgery were randomized into two groups. Patients in the intervention group received a loading dose of dexmedetomidine 0·6 μg/kg 10 min before induction of anaesthesia followed by a continuous infusion (0·5 μg per kg per h) until 1 h before the end of surgery. Patients in the control group received volume-matched normal saline in the same schedule. The primary outcome was the incidence of delirium during the first 5 days after surgery. Delirium was assessed with the Confusion Assessment Method (CAM) for non-ventilated patients and CAM for the Intensive Care Unit for ventilated patients.

Results

In total, 309 patients who received dexmedetomidine and 310 control patients were included in the intention-to-treat analysis. The incidence of delirium within 5 days of surgery was lower with dexmedetomidine treatment: 5·5 per cent (17 of 309) versus 10·3 per cent (32 of 310) in the control group (relative risk (RR) 0·53, 95 per cent c.i. 0·30 to 0·94; P = 0·026). The overall incidence of complications at 30 days was also lower after dexmedetomidine (19·4 per cent (60 of 309) versus 26·1 per cent (81 of 310) for controls; RR 0·74, 0·55 to 0·99, P = 0·047).

Conclusion

Intraoperative dexmedetomidine halved the risk of delirium in the elderly after major non-cardiac surgery. Registration number: ChiCTR-IPR-15007654 (www.chictr.org.cn).

Beneficial effects of xenon inhalation on behavioral changes in a valproic acid-induced model of autism in rats

BACKGROUND

Xenon (Xe) is a noble gas that has been used for the last several decades as an anesthetic during surgery. Its antagonistic effect on glutamate subtype of NMDA (N-methyl-D-aspartate) receptors resulted in evaluation of this gas for treatment of CNS pathologies, including psychoemotional disorders. The aim of this study was to assess the behavioral effects of acute inhalation of subanesthetic concentrations of Xe and to study the outcomes of Xe exposure in valproic acid (VPA)-induced rodent model of autism.

METHODS

We have conducted two series of experiments with a battery of behavioral tests aimed to evaluate locomotion, anxiety- and depression-like behavior, and social behavior in healthy, VPA-treated and Xe-exposed young rats.

RESULTS

We have shown that in healthy animals Xe exposure resulted in acute and delayed decrease of exploratory motivation, partial decrease in risk-taking and depressive-like behavior as well as improved sensorimotor integration during the negative geotaxis test. Acute inhalations of Xe in VPA-exposed animals led to improvement in social behavior, decrease in exploratory motivation, and normalization of behavior in forced-swim test.

CONCLUSION

Behavioral modulatory effects of Xe are probably related to its generalized action on excitatory/inhibitory balance within the CNS. Our data suggest that subanesthetic short-term exposures to Xe have beneficial effect on several behavioral modalities and deserves further investigation.

Apoptotic and Proteolytic Attributes and Metabolomic Changes in Postmortem Muscles from Pigs Subjected to Post-Weaning Transport at Different Seasons

ObjectivesPost-weaning transport of pigs was commonly practiced in the swine industry, however, adversely impact animal growth and well-being due to concurrent stress from weaning and transport. Further, our recent study found that post-weaning transport may have long-term effects on final pork quality attributes in terms of inferior texture and water-holding capacity. Heat shock proteins (HSPs) are anti-apoptotic chaperone proteins, protecting against apoptosis under a variety of cell death stimuli including postmortem muscle conversion process. While a potential role of apoptosis in meat tenderization has been proposed, how early life stress influences apoptotic/proteolytic process and metabolism of postmortem muscles is largely unknown. Thus, the study objective was to evaluate apoptotic and proteolytic attributes and metabolomic changes in postmortem muscles of market weight pigs exposed to early life transport/weaning stress at two seasons.Materials and MethodsTwo repetitions of newly weaned pigs (N = 480) were transported for 12 h in a trailer truck during July 2016 (SUMMER) and April 2017 (SPRING) in north-central Indiana. Upon reaching market weight, 10 animals were randomly chosen from each season and slaughtered in January 2017 and September 2017, respectively. Pairs of longissimus dorsi and psoas major muscles from each carcass were separated at 1d and 7d postmortem. Proteolytic and apoptotic factors including desmin, troponin T, calpain 1, HSP27, and aβ-crystallin were quantified using Western-blot assays, and mitochondria membrane permeability (MMP) was evaluated. Metabolome profiles of 1d samples were analyzed using the GC-TOF-MS/MS platform. Multivariate analyses PCA and PLS-DA were used to determine changes of metabolites. Data were analyzed using PROC MIXED of SAS to compare the traits across season, muscle, and aging effects.ResultsPreviously, SUMMER pigs were reported showing decreased body weight, muscling, and fat deposition, as well as increased shear force and water loss during aging. In the present study, SPRING muscles exhibited increases in calpain 1 autolysis and structural protein degradation, coincided with accelerated apoptosis shown as higher MMP compared to the SUMMER counterparts (P < 0.05). Moreover, PCA and PLS-DA clustering indicated distinct metabolome profiles affected by season and muscle. Seasonal effect mainly altered lipid, glucose, and nitrogen metabolism. A group of 16C to 18C fatty acids were increased in SPRING, probably due to increased lipid anabolism during warm growing/finishing season. Changes of urea, ornithine, aspartic acid, and 5’methylthioadenosine suggested increased amino acid catabolism in SUMMER, corroborating the decreased lean and fat accretion. Seasonal changes of key metabolites related to stress response, including histidine, GABA, and ascorbic acid, suggested increased stress defense in SUMMER pigs, which implied the suppression of apoptotic and proteolytic activities.ConclusionTaken together, SUMMER pigs showed suppressed onset of apoptosis with compromised growth and meat quality, possibly due to alternations in seasonal metabolic response. This may in turn affect the proteolytic potential of early postmortem muscles. Further studies elucidating the involvement of apoptotic process in proteolytic activities in postmortem muscles should be warranted.

H19 promotes the proliferation of osteocytes by inhibiting p53 during fracture healing

OBJECTIVE

We explored the possible mechanism underlying the expression change of H19 during fracture healing.

MATERIALS AND METHODS

A total of 18 male SD mice aged from 6-8 weeks old (18.5-24.6 g) were selected to establish tibial fracture models. The left tibia undergoing sham surgery was considered as the control group, and the right tibia undergoing sawing treatment was considered as the experimental group. The control tibia and fracture tibia from three mice were harvested at six time points after operation, respectively. QRT-PCR was utilized to detect the changes of H19 and p53 mRNA expression.

RESULTS

Compared with the control group, the expression of H19 in the experimental group was significantly increased at 4, 8, and 12 d. However, there was no significant difference in the expression of H19 between the experimental group and the control group at 16, 20, and 24 d. The proliferation of chondrocytes and osteoblasts from mouse and human was significantly inhibited, and the apoptosis was significantly increased after interference of H19. As p19 plays important roles in diverse biological process, we detected the expression level of p19 after inference of H19. In addition, knockdown of H19 significantly up-regulated the expression of p53 in osteoblast cell lines, while the down-regulation of p53 expression reversed the proliferation of osteoblasts.

CONCLUSIONS

H19, as a molecular marker for promoting fracture healing, promote the proliferation of osteocytes by inhibiting the expression of p53.

Ageing affects the proliferation and mineralization of rat dental pulp stem cells under inflammatory conditions

AIM

To comparatively evaluate changes in the proliferation and mineralization abilities of dental pulp stem cells (DPSCs) from juvenile and adult rats in a lipopolysaccharide (LPS)-induced inflammatory microenvironment to provide a theoretical basis for the age-related differences observed in DPSCs during repair of inflammatory injuries.

METHODOLOGY

DPSCs were isolated from juvenile (JDPSCs) and adult rats (ADPSCs), and senescence-associated β-galactosidase staining was used to compare senescence between JDPSCs and ADPSCs. Effects of LPS on JDPSCs and ADPSCs proliferation were investigated by cell counting kit-8 assays and flow cytometry. Alizarin red staining, quantitative reverse transcription polymerase chain reaction and Western blot assay were used to examine the effects of LPS on mineralization-related genes and proteins in JDPSCs and ADPSCs. Immunohistochemistry was used to compare interleukin-1β (IL-1β) and osteocalcin (OCN) expression in the pulpitis model. Unpaired Student's t-tests and one-way anova were used for statistical analysis.

RESULTS

DPSCs were isolated from juvenile and adult rat dental pulp tissues. At low concentrations (0.1-1 μg mL^-1 ), LPS significantly promoted the proliferation of JDPSCs (P < 0.01) and ADPSCs (P < 0.01 or P < 0.05), with the effect being stronger in JDPSCs than in ADPSCs. In addition, mineralized nodules and the expression of mineralization-related genes (OCN, DSPP, ALP, BSP) increased significantly after stimulation with LPS (0.5 μg mL^-1 ) in JDPSCs and ADPSCs (P < 0.01 or P < 0.05), and JDPSCs displayed a more obvious increase than ADPSCs. Western blots revealed OCN and ALP expression levels in JDPSCs treated with LPS were significantly upregulated (P < 0.05); meanwhile, ALP expression in ADPSCs increased slightly but significantly (P < 0.05), and OCN expression was not affected. Finally, IL-1β expression was significantly higher (P < 0.05) and OCN expression was significantly lower (P < 0.05) in the inflamed dental pulp of adult rats than in juvenile rats.

CONCLUSIONS

A certain degree of inflammatory stimulation promoted the proliferation and mineralization of DPSCs; however, this effect declined with age. The DPSCs of adult donors in an inflammatory microenvironment have a weaker repair ability than that of juvenile donors, who are better candidates for tissues damage repair.

Abstract P2-01-13: The splicing factor PHD finger protein 5A inhibits apoptosis to promote breast cancer progression

Background: All the widely accepted hallmarks of cancer are known to be affected by aberrant splicing (AS), and splicing dysregulation itself is considered a valuable therapeutic target. Understanding the AS that promote cancer progression is crucial for the development of effective strategies for treating breast cancer.

Methods: An in vivo CRISPR screen targeting RNA-binding proteins (RBPs) was performed to reveal the key splicing modulator (PHD finger protein 5A, PHF5A) of breast tumor progression. Immunohistochemistry method and survival analysis were performed using a tissue microarray (TMA) containing 450 breast carcinoma. Proliferation, transwell migration and in vivo tumor formation assays were utilized to assess the biological role of PHF5A. RNA sequencing and RT-PCR assay were used to identify PHF5A-regulated AS events in breast cancer cells. Biological functions and molecular pathways of the affected genes were investigated through a gene ontology (GO) analysis. Flow cytometry and Western blot analysis were used for apoptotic assessments. The correlation between PHF5A expression and AS events was further analysed using mRNA-Seq data of 40 paired breast cancer and adjacent normal breast tissues. And the correlation between the levels of PHF5A and cleaved caspase-3 were evaluated in the TMA.

Results: According to RNA sequencing analysis of MCF10 cell series (MCF10A, MCF10AT, MCF10DCIS and MCF10CA1a), 159 RBPs were found to be up-regulated in cancer cells compared with non-cancer cells. And the CRISPR screen targeting these 159 RBPs systematically identified highest-ranking genes including PHF5A. In TMA cohort, high PHF5A expression was correlated with poor disease-free survival. PHF5A is frequently up-regulated in breast cancer and is essential for cancer cell proliferation, migration and tumor formation. Knockdown of PHF5A induces genome-wide AS events. The RT-PCR assay of MCF10CA1a cells showed that splicing changes of nine arbitrarily selected target genes were all modulated by PHF5A. GO analysis showed that PHF5A-regulated AS events were involved in apoptotic and anti-apoptotic pathways, among which FAS-activated serine/threonine kinase (FASTK) AS showed significant PSI (percent spliced in) difference. PHF5A knockdown appeared to switch full-length FASTK (FASTK-L) to an intron 5-retained variant (herein termed FASTK short, FASTK-S) in MCF10CA1a cells. The knockdown of PHF5A resulted in cleavage of caspase-3 and poly-ADP-ribose polymerase and conversion of the FASTK-L (61 kDa) and FASTK-S (42 kDa) proteins. Intriguingly, cells transduced with exogenous FASTK-S showed the most significant apoptotic effect, whereas the FASTK-L group presented a decreased apoptotic effect. The PHF5A ratios of paired non-tumor to tumor tissue were negatively correlated with the FASTK PSI differences between non-tumor and tumor tissues. A strong negative correlation was found between the PHF5A and cleaved caspase-3 levels in TMA.

Conclusions: PHF5A depletion sensitizes cancer cells to apoptotic signaling partially through AS-mediated FASTK isoform conversion. This apoptotic suppressor plays a key role in breast cancer progression and acts as a prognostic indicator, and should be critically considered for optimization of the current therapeutic strategy.

Citation Format: Zheng Y-Z, Xue M-Z, Shen H-J, Li X-G, Ma D, Gong Y, Hu X, Shao Z-M. The splicing factor PHD finger protein 5A inhibits apoptosis to promote breast cancer progression [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-13.

Abstract P3-08-11: Multi-omics profiling reveals distinct molecular features in young and elderly triple negative breast cancer

Purpose

Age at breast cancer diagnosis not only predicts clinical outcome, but also indicates distinct molecular features thus we can choose the most appropriate treatment strategies. Yet little is known about the molecular profile of young and elderly triple negative breast cancers (TNBCs).

Methods

Clinical, genomic and transcriptome features of young (&lt;40 year-olds) and elderly (≥65 year-olds) TNBC patients were studied in a cohort of 473 TNBCs from Fudan University Shanghai Cancer Center.

Results

In this study, 50, 354 and 69 patients were &lt;40, 40–64 and ≥65 years of age, respectively. Young TNBCs had more relapse or metastasis within the first 2 years after surgery (P=0.036) which was also significant in the basal-like subgroup (P=0.004), while elderly TNBCs were more likely to be luminal androgen receptor (LAR) subtype (46%) harboring frequent PIK3CA and KMT2C/KMT2D somatic mutations, with more fibrosis or mesenchymal-like (MES) subtype (in the basal-like subgroup) and featured by significantly lower Ki-67 index. Gene set enrichment analyses revealed that young TNBCs showed elevated expression of genes involved in cell cycle, nucleotide metabolism and DNA damage repair. In further discussion on nucleotide metabolism, TYMS, a crucial gene encoding thymidylate synthase while is also the target of fluorouracil and capecitabine, were identified to be enriched in young TNBCs independent of molecular subtype in both our cohort (adjusted P&lt;0.001) and METABRIC (adjusted P=0.027). We next studied DNA damage features and found that while TNBCs of different age groups had comparable somatic mutation load, their mutations had distinct generation mechanism that homologous recombination deficiency (HRD) related signature and Aging related signature tend to be enriched in younger and elder patients, respectively. We also observed higher germline BRCA1 mutation rate in young TNBCs (23%). Interestingly, while germline BRCA2 mutation rate was comparable among the groups, copy number (CN) loss of Chr13q13 (with BRCA2 in the 'peak') was almost exclusively found in young patients (adjusted P&lt;0.05). We also found enriched CN loss at Chr15q13 (with FAN1 in the 'peak') and CN amplification at Chr1p34 (with KDM4A in the 'peak') in young patients. These two events significantly affected the expression levels of FAN1 and KDM4A, respectively, and were both corrected with genomic based HRD indexes.

Conclusions

TNBCs of different age had distinct clinical and molecular features. We should pay attention to that nearly half of the TNBCs diagnosed at 65 years-old or later were not basal-like cancers but a special group with positive AR staining. Taking together with the higher fibrosis/MES proportion in elderly TNBC, we should reconsider the benefit of specific treatment strategies (like neoadjuvant chemotherapy) in these patients. The young TNBCs were characterized by activated cell cycle, elevated nucleotide metabolism (especially TYMS expression and corresponding pyrimidine metabolism) and enhanced DNA damage (especially HRD). These molecular features supported the aggressive phenotypes of young TNBC, while also provide us with potential therapeutic strategies.

Citation Format: Ma D, Jiang Y-Z, Xie M-D, Xiao Y, Zhao S, Shao Z-M. Multi-omics profiling reveals distinct molecular features in young and elderly triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-11.

Abstract P3-07-07: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Jiang Y-Z, Ma D, Suo C, Shi J, Xue M, Stover DG, Verschraegen C, Kaklamani V, Wang P, Shi L, Huang W, Shao Z-M. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-07-07.

Abstract P4-06-24: Microenvironment heterogeneity of triple-negative breast cancer reveals distinct immune escape mechanisms and potential driver events

Background The microenvironment phenotypes strongly affect the immunotherapeutic strategies for triple-negative breast cancer (TNBC). Although the multi-omics profile of TNBC has been comprehensively characterized, few studies have focused on the microenvironment phenotypes of TNBC.

Methods With multi-omics data for the largest single-center TNBC cohort (n=386), we first established a TNBC-specific microenvironment cell signature. We further used single sample gene set enrichment analysis to calculate the relative number of microenvironment cell subsets in each sample. Then, we performed k-means clustering to classify the TNBC microenvironment phenotypes into heterogeneous clusters. Furthermore, we systematically analyzed the extrinsic and intrinsic immune escape mechanisms of different TNBC microenvironment clusters. In addition, we explored genomic alterations that might decrease immune infiltration in certain TNBC microenvironment clusters.

Results We classified the TNBC microenvironment phenotypes into three heterogeneous clusters. Cluster 1 (type 1 “cold tumor”) had low microenvironment cells infiltration. Cluster 2 (type 2 “cold tumor”) was characterized by resting innate immune cells, fibroblasts and endothelial cells infiltration. Cluster 3 (“hot tumor”) was featured by adaptive immune cells infiltration. Analysis of immune escape mechanism revealed that an incapability to attract innate immune cells (resulting in failure of adaptive immunity) led to immune escape of cluster 1. The chemotaxis but inactivation of innate immunity (also leading to failure of adaptive immunity) and low tumor antigen burden resulted in immune escape of cluster 2. High expression of immune checkpoint molecules contributed to immune escape of cluster 3. In addition, we found that tumor infiltrating lymphocytes (TILs) were positively correlated with immune checkpoint molecules expression, while mutation load was negatively correlated with those indicators in triple-negative breast cancer. Analysis of enrichment pathways, mutations and somatic copy number variations between the “cold tumor” and “hot tumor” clusters revealed that amplification of MYC and activation of MYC-related pathways might decrease the immune infiltration of cluster 1. Mutations in PI3K-AKT pathway members and activation of fibroblasts-related pathways might decrease the immune infiltration of cluster 2.

Conclusion Utilizing the largest single-center TNBC cohort with multi-omics data, our study first revealed the heterogeneity of the TNBC microenvironment, with translational significance both clinically and biologically. First, we identified a subtype of “hot tumor” in TNBC (cluster 3), for which immune checkpoint blockers (ICBs) might be effective. TILs and immune checkpoint molecules expression but not mutation load might predict the efficacy of ICBs. Second, we presumed some genomic alterations that might drive “cold tumor” formation in TNBC. Our study represents a step toward personalized immunotherapy for TNBC patients.

Key Words triple-negative breast cancer, multi-omics, microenvironment heterogeneity, immune escape

Citation Format: Xiao Y, Ma D, Zhao S, Jiang Y-Z, Shao Z-M. Microenvironment heterogeneity of triple-negative breast cancer reveals distinct immune escape mechanisms and potential driver events [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-24.

Abstract P2-08-33: A novel seven-gene signature predicts prognosis in early-stage triple-negative breast cancer

Purpose:

Chemotherapy remains the only systemic treatment option for patients with triple-negative breast cancer (TNBC). However, due to the heterogeneity of TNBC, not all patients benefit from chemotherapy, especially those with early-stage disease. In order to improve prognostic assessment and reduce unnecessary adjuvant systemic therapy in these patients, we have developed a novel seven-gene signature.

Experimental Design:

With the ComBat method, we integrated the results from 150 transcriptome microarrays samples and 246 RNA-seq samples of early-stage TNBC patients, and identified mRNAs associated with recurrence-free survival (RFS) using Lasso-Cox model, We further analyzed these TNBC samples and compared them with 60 paired normal breast tissues (40 samples from RNA-seq and 20 samples from microarrays) to identify tumor-specific mRNAs. Twenty-one overlapped mRNAs of the RFS-associated mRNAs and the tumor-specific mRNAs are selected as candidate mRNAs. An additional 371 samples of frozen primary tumors were then collected from early-stage TNBC patients (mean follow-up of 45 months) and randomly divided into two sets: a training set (n = 186) and a validation (n = 185) set. Expression level of candidate mRNAs in these samples were measured using RT-qPCR assays, and a seven-gene signature was built through all subset regression in the training set. The prognostic and predictive accuracy of our signature was tested in the validation set and other public databases (GSE5327, GSE2034 and METABRIC).

Results:

Twenty-one candidate mRNAs were identified in early-stage TNBC patients, from which we developed a novel seven-gene signature (recurrence risk score [mRNA signature] = 1.108*TMEM101 - 0.213*KRT5 - 0.315*ACAN - 0.464*LCA5 + 0.446*RPP40 - 0.373*LAGE3 - 0.257*CDKL2). Patients in the training set were classified into high- or low-risk group based on our seven-gene signature and an optimum cut-off score derived from x-tile. The patients in high-risk group were more likely to suffer from recurrence (HR, 2.718; 95% confidence interval [CI], 1.928–3.726, P= 0.001), and a time-dependent receiver operating curve showed that the seven-gene mRNA signature had a better prognostic value than the clinicopathologic risk factors in both training set and validation set. The prognostic and predictive accuracy of the signature was also validated in the METABRIC and two other public GEO databases (GSE5327 and GSE2034). The time-dependent receiver operating curve showed that this signature had an area under the curve (AUC) of 0.742 (95% CI, 0.705-0.773) in METABRIC, 0.716 (95% CI, 0.682-0.739) and 0.723 (95% CI, 0.683-0.756) in GSE5327 and GSE2034 respectively.

Conclusion:

In this study, we developed a novel seven-gene signature which can provide additional prognostic information and may guidance in identifying early-stage TNBC patients eligible for adjuvant therapy or reduction of chemotherapy. To our knowledge, this is the first study investigating the prognostic potential of mRNA signature in early-stage triple-negative breast cancer. Our novel signature may provide an opportunity for de-escalating treatment in early-stage TNBC patients in the future.

Citation Format: Ren Y, Jiang Y, Zuo W, Xu X, Jin X, Ma D, Shao Z. A novel seven-gene signature predicts prognosis in early-stage triple-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-33.