Mechanisms of tumor immune escape in triple-negative breast cancers (TNBC) with and without mutated BRCA 1

Profiling Breast Tumor Heterogeneity and Identifying Breast Cancer Subtypes Through Tumor-Associated Immune Cell Signatures and Immuno Nano Sensors

Breast cancer is a complex and heterogeneous disease with varying cellular, genetic, epigenetic, and molecular expressions. The detection of intratumor heterogeneity in breast cancer poses significant challenges due to its complex multifaceted characteristics, yet its identification is crucial for guiding effective treatment decisions and understanding the disease progression. Currently, there exists no method capable of capturing the full extent of breast tumor heterogeneity. In this study, the aim is to identify and characterize metabolic heterogeneity in breast tumors using immune cells and an ultrafast laser-fabricated Immuno Nano Sensor. Combining spectral markers from both Natural Killer (NK) and T cells, a machine-learning approach is implemented to distinguish cancer from healthy samples, identify primary versus metastatic tumors, and determine estrogen receptor (ER)/progesterone receptor (PR) status at the single-cell level. The platform successfully distinguished heterogeneous breast cancer samples from healthy individuals, achieving 97.8% sensitivity and 92.2% specificity, and accurately identified primary tumors from metastatic tumors. Characteristic spectral signatures allow for discrimination between ER/PR-positive and negative tumors with 97.5% sensitivity. This study demonstrates the potential of immune cell-based metabolic profiling in providing a comprehensive assessment of breast tumor heterogeneity and paving the way for minimally invasive liquid biopsy approaches in breast cancer diagnosis and management.

Associations between KIR/KIR-ligand genotypes and clinical outcome for patients with advanced solid tumors receiving BEMPEG plus nivolumab combination therapy in the PIVOT-02 trial

Bempegaldesleukin (BEMPEG), a CD122-preferential IL2 pathway agonist, has been shown to induce proliferation and activation of NK cells. NK activation is dependent on the balance of inhibitory and excitatory signals transmitted by NK receptors, including Fc-gamma receptors (FCγRs) and killer immunoglobulin-like receptors (KIRs) along with their KIR-ligands. The repertoire of KIRs/KIR-ligands an individual inherits and the single-nucleotide polymorphisms (SNPs) of FCγRs can influence NK function and affect responses to immunotherapies. In this retrospective analysis of the single-arm PIVOT-02 trial, 200 patients with advanced solid tumors were genotyped for KIR/KIR-ligand gene status and FCγR SNP status and evaluated for associations with clinical outcome. Patients with inhibitory KIR2DL2 and its ligand (HLA-C1) observed significantly greater tumor shrinkage (TS, median change -13.0 vs. 0%) and increased PFS (5.5 vs. 3.3 months) and a trend toward improved OR (31.2 vs. 19.5%) compared to patients with the complementary genotype. Furthermore, patients with KIR2DL2 and its ligand together with inhibitory KIR3DL1 and its ligand (HLA-Bw4) had improved OR (36.5 vs. 19.6%), greater TS (median change -16.1 vs. 0%), and a trend toward prolonged PFS (8.4 vs. 3.6 months) as compared to patients with the complementary genotype. FCγR polymorphisms did not influence OR/PFS/TS.These data show that clinical response to BEMPEG plus nivolumab treatment in the PIVOT-02 trial may be associated with the repertoire of KIR/KIR-ligands an individual inherits. Further investigation and validation of these results may enable KIR/KIR-ligand genotyping to be utilized prospectively for identifying patients likely to benefit from certain cancer immunotherapy regimens.

Prognostic value of neutrophil-to-lymphocyte ratio for patients with triple-negative breast cancer: A meta-analysis

We aimed to evaluate the prognostic role of the neutrophil-to-lymphocyte ratio (NLR) in patients with triple-negative breast cancer (TNBC). We searched the PubMed Database, Cochrane Library, Web of science, and Embase. Overall survival (OS), disease-free survival (DFS), and hazard ratio (HR) were the endpoints of the study. Eleven studies involving 2355 patients with TNBC were included in this meta-analysis. Among them, 10 studies involving 2069 patients with TNBC investigated the role of NLR in predicting OS; elevated NLR was associated with poor prognosis (hazard ratio [HR]: 2.48, 95% confidence interval [CI]: 2.03-3.03, P < 0.001). Ten studies involving 2054 patients with TNBC explored the role of NLR in predicting DFS; elevated NLR was associated with a significantly worse prognosis with a pooled HR of 2.20 (95% CI: 1.88-2.58, P < 001). This meta-analysis suggests that patients with TNBC who have a higher NLR have poorer prognoses. As a clinical parameter that we can easily obtain, NLR might be a potential predictor of patients' survival, and may be useful for physicians' treatment decisions.

Regulatory T cells: Their role in triple-negative breast cancer progression and metastasis

Triple-negative breast cancer (TNBC) is an aggressive and immunogenic subtype of breast cancer. This tumorigenicity is independent of hormonal or HER2 pathways because of a lack of respective receptor expression. TNBC is extremely prone to drug resistance and early recurrence because of T-regulatory cell (Treg) infiltration into the tumor microenvironment (TME) in addition to other mechanisms like genomic instability. Tumor-infiltrating Tregs interact with both tumor and stromal cells as well as extracellular matrix components in the TME and induce an immune-suppressive phenotype. Hence, treatment of TNBC with conventional therapies remains challenging. Understanding the protective mechanism of Tregs in shielding TNBC from antitumor immune responses in the TME will pave the way for developing novel, immune-based therapeutics. The current review focuses on the role of tumor-infiltrating Tregs in tumor progression and metabolic reprogramming of the TME. The authors have extended their focus to oncotargeting Treg-mediated immune suppression in breast cancer. Because of its potential role in the TME, modulating Treg activity may provide a novel strategic intervention to combat TNBC. Both under laboratory conditions and in clinical trials, currently available anticancer drugs and natural therapeutics as potential agents for targeting Tregs are explored.

Dual Targeting of Cancer Cells and MMPs with Self-Assembly Hybrid Nanoparticles for Combination Therapy in Combating Cancer

The co-delivery of chemotherapeutic agents and immune modulators to their targets remains to be a great challenge for nanocarriers. Here, we developed a hybrid thermosensitive nanoparticle (TMNP) which could co-deliver paclitaxel-loaded transferrin (PTX@TF) and marimastat-loaded thermosensitive liposomes (MMST/LTSLs) for the dual targeting of cancer cells and the microenvironment. TMNPs could rapidly release the two payloads triggered by the hyperthermia treatment at the site of tumor. The released PTX@TF entered cancer cells via transferrin-receptor-mediated endocytosis and inhibited the survival of tumor cells. MMST was intelligently employed as an immunomodulator to improve immunotherapy by inhibiting matrix metalloproteinases to reduce chemokine degradation and recruit T cells. The TMNPs promoted the tumor infiltration of CD3+ T cells by 2-fold, including memory/effector CD8+ T cells (4.2-fold) and CD4+ (1.7-fold), but not regulatory T cells. Our in vivo anti-tumor experiment suggested that TMNPs possessed the highest tumor growth inhibitory rate (80.86%) compared with the control group. We demonstrated that the nanoplatform could effectively inhibit the growth of tumors and enhance T cell recruitment through the co-delivery of paclitaxel and marimastat, which could be a promising strategy for the combination of chemotherapy and immunotherapy for cancer treatment.

Epigenetic quantification of circulating immune cells in peripheral blood of triple-negative breast cancer patients

BACKGROUND

A shift in the proportions of blood immune cells is a hallmark of cancer development. Here, we investigated whether methylation-derived immune cell type ratios and methylation-derived neutrophil-to-lymphocyte ratios (mdNLRs) are associated with triple-negative breast cancer (TNBC).

METHODS

Leukocyte subtype-specific unmethylated/methylated CpG sites were selected, and methylation levels at these sites were used as proxies for immune cell type proportions and mdNLR estimation in 231 TNBC cases and 231 age-matched controls. Data were validated using the Houseman deconvolution method. Additionally, the natural killer (NK) cell ratio was measured in a prospective sample set of 146 TNBC cases and 146 age-matched controls.

RESULTS

The mdNLRs were higher in TNBC cases compared with controls and associated with TNBC (odds ratio (OR) range (2.66-4.29), all P_adj. < 1e-04). A higher neutrophil ratio and lower ratios of NK cells, CD4 + T cells, CD8 + T cells, monocytes, and B cells were associated with TNBC. The strongest association was observed with decreased NK cell ratio (OR range (1.28-1.42), all P_adj. < 1e-04). The NK cell ratio was also significantly lower in pre-diagnostic samples of TNBC cases compared with controls (P = 0.019).

CONCLUSION

This immunomethylomic study shows that a shift in the ratios/proportions of leukocyte subtypes is associated with TNBC, with decreased NK cell showing the strongest association. These findings improve our knowledge of the role of the immune system in TNBC and point to the possibility of using NK cell level as a non-invasive molecular marker for TNBC risk assessment, early detection, and prevention.

Reconstituting Immune Surveillance in Breast Cancer: Molecular Pathophysiology and Current Immunotherapy Strategies

Over the past 50 years, breast cancer immunotherapy has emerged as an active field of research, generating novel, targeted treatments for the disease. Immunotherapies carry enormous potential to improve survival in breast cancer, particularly for the subtypes carrying the poorest prognoses. Here, we review the mechanisms by which cancer evades immune destruction as well as the history of breast cancer immunotherapies and recent developments, including clinical trials that have shaped the treatment of the disease with a focus on cell therapies, vaccines, checkpoint inhibitors, and oncolytic viruses.

Comprehensive Analysis of Regulatory Factors and Immune-Associated Patterns to Decipher Common and BRCA1/2 Mutation-Type-Specific Critical Regulation in Breast Cancer

Background: BRCA1/2 mutations are closely related to high lifetime risk of breast cancer (BC). The objective of this study was to identify the genes, regulators, and immune-associated patterns underlying disease pathology in BC with BRCA1/2 somatic mutations and their associations with clinical traits. Methods: RNA sequencing data and clinical information from The Cancer Genome Atlas (TCGA; N = 36 BRCA1-mutant BC; N = 49 BRCA2-mutant BC; and N = 117 BRCA1/2-wild-type BC samples) were used for discovery, which included consensus network analysis, function enrichment, and analysis of hub genes; other TCGA data (N = 117 triple-negative BC) and two Gene Expression Omnibus database expression profiles were used as validation cohorts. Results: Consensus network analysis helped to identify specific co-expressed modules that showed positive correlations with tumor stage, number of positive lymph nodes, and margin status in BRCA1/2-mutant BC but lacking correlations in BRCA1/2-wild-type BC. Functional enrichment suggested potential mechanisms in BRCA1/2 carriers that could regulate the cell cycle, immune response, cellular metabolic processes, and cell migration, via enriched pathways including p53 and JAK-STAT signaling. Consensus network analysis identified the specific and common carcinogenic mechanisms involving BRCA mutations. Regulators cross-linking these modules include E2F or IRF transcription factor family, associated with cell cycle or immune response regulation module, respectively. Eight hub genes, including ISG15, BUB1, and TTK, were upregulated in several BRCA1/2-mutant BC datasets and showed prognostic value in BC. Furthermore, their genetic expression was related to higher levels of immune infiltration in BRCA1/2-mutant BC, which manifested as recruitment of T helper cells (Th1 cells), follicular helper T cells, and regulatory T cells, and T cell exhaustion. Moreover, important indicators for evaluation of BC immunotherapy, tumor mutational burden and neoantigen load also positively correlated with expression of some hub genes. Conclusion: We constructed a BRCA1/2 mutation-type-specific co-expressed gene network with related transcription factors and immune-associated patterns that could regulate and influence tumor metastasis and immune microenvironment, providing novel insights into the pathological process of this disease and the corresponding BRCA mutations.

Study on the Killing Effect of γδT Cells Activated by Rukangyin on Breast Cancer MDA-MB-231 Cells

OBJECTIVE

To investigate the killing effect of rukangyin (RKY) activated γδT cells on breast cancer cells MDA-MB-231 and to provide a basis for Chinese medicine combined with immunotherapy for breast cancer.

METHODS

Thus, study isolates peripheral blood mononuclear cells (PBMC) and uses CCK8 to select the optimal concentration of Rukang drink, ZOL (zoledronic acid), and PHA (phytoagglutinin) to activate γδT cells. There are 8 groups including the ① PBMC control group, ② RKY group, ③ ZOL group, ④ PHA group, ⑤RKY+ZOL group, ⑥RKY+PHA group, ⑦ZOL+PHA group, and ⑧ RKY+ZOL+PHA group. At 0 and 14 days of culture, cell viability and γδT cell expansion were detected by flow cytometry. The 8 groups of amplified γδT were cocultured with breast cancer MDA-MB-231 cells labeled with fluorescent dye CFSE at a ratio of 10 : 1 to determine the lethality of γδT cells on breast cancer MDA-MB-231 cells.

RESULTS

The optimal concentrations of RKY, ZOL, and PHA to activate γδT cell proliferation were 4.5 mg/l, 3 μM, and 60 μg/ml, respectively. On day 0 of culture, the values ( x ¯ ± s , %) of γδT cells in groups ① to ⑧ were 3.50 ± 0.72, 3.97 ± 0.45, 3.99 ± 0.15, 4.37 ± 0.24, 4.47 ± 0.97, 4.59 ± 1.35, 3.45 ± 0.40, and 3.89 ± 0.48, while when a comparison between groups was made, F = 1.093 and p = 0.412; there is no significant difference between groups. Besides, when being cultured for 14 days, the values ( x ¯ ± s , %) of γδT cells in groups ① to ⑧ were 4.77 ± 0.78, 23.22 ± 2.73, 26.4 ± 0.92, 28.66 ± 1.43, 27.99 ± 1.10, 30.21 ± 1.91, 32.51 ± 0.74, and 33.21 ± 0.42. Then, based on the comparison between groups, F = 119.917 and p < 0.001, there are obvious statistical differences between groups. Furthermore, the expansion values of γδT cells were compared before and after culture for 0 and 14 days. The t values of group ① to group ⑧ were 2.072, 12.051, 41.641, 29.015, 27.777, 18.972, 59.836, and 79.622. Except for the PBMC control group (p = 0.107), there are significant statistical differences (p < 0.001). The number of γδT cell expansion at 14 days was the RKY+ZOL+PHA group>ZOL+PHA group>RKY+PHA group>PHA group>RKY+ZOL group>ZOL group>RKY group>PBMC control group. From group ① to group ⑧, the γδT cell expansion multiples were 1.14 ± 0.44, 5.25 ± 0.77, 5.70 ± 0.89, 6.05 ± 1.03, 6.21 ± 0.09, 6.76 ± 1.46, 7.52 ± 1.05, and 7.97 ± 1.55, respectively, while the comparison between groups was F = 17.772 and p < 0.001. As for the amplification factor, there was RKY+ZOL+PHA group>ZOL+PHA group>RKY+PHA group>RKY+ZOL group>PHA group>ZOL group>RKY group>PBMC control group. In the killing experiment, the killing rate ( x ¯ ± s , %) of group ① to group ⑧ was 1.08 ± 0.03, 1.89 ± 0.14, 1.22 ± 0.11, 1.31 ± 0.09, 1.48 ± 0.10, 2.02 ± 0.21, 2.18 ± 0.27, and 2.37 ± 0.35, whereas the comparison between groups was F = 20.498 and p < 0.001. In terms of killing rate, there was RKY+ZOL+PHA group>ZOL+PHA group>RKY+PHA group>RKY group>RKY+ZOL group>PHA group>ZOL group>PBMC control group.

CONCLUSION

Rukangyin can increase the lethality of γδT cells against MDA-MB-231 cells by activating the proliferation of γδT cells, which provides a basis for Chinese medicine combined with immunotherapy for breast cancer.

Adaptive NK Cell Therapy Modulated by Anti-PD-1 Antibody in Gastric Cancer Model

Recently, adaptive NK cell therapy has become a promising treatment but has limited efficacy as a monotherapy. The identification of immune checkpoint inhibitor (ICI) molecules has opened a new horizon of immunotherapy. Herein, we aimed to demonstrate the cytotoxic effects of a polytherapy consisting of ex vivo expanded IL-2-activated NK cells combined with human anti-PD-1 antibody as an important checkpoint molecule in a xenograft gastric cancer mouse model. EBV-LCL cell is used as a feeder to promote NK cell proliferation with a purity of 93.4%. Mice (NOG, female, 6–8 weeks old) with xenograft gastric tumors were treated with PBS, ex vivo IL-2-activated NK cells, IL-2-activated NK cell along with human anti-PD-1 (Nivolumab), and IL-2-activated pretreated NK cells with anti-PD-1 antibody. The cytotoxicity of ex vivo expanded NK cells against MKN-45 cells was assessed by a lactate dehydrogenase (LDH) assay. Tumor volume was evaluated for morphometric properties, and tumor-infiltrating NK cells were assessed by immunohistochemistry (IHC) and quantified by flow cytometry. Pathologic responses were considered by H and E staining. Ex vivo LDH evaluation showed the cytotoxic potential of treated NK cells against gastric cancer cell line. We indicated that the adoptive transfer of ex vivo IL-2-activated NK cells combined with anti-PD-1 resulted in tumor growth inhibition in a xenograft gastric cancer model. Mitotic count was significantly decreased (*p < 0.05), and the tumor was associated with improved infiltration of NK cells in the NK-anti-PD-1 pretreated group (*p < 0.05). In conclusion, the combination approach of activated NK cells and anti-PD-1 therapy results in tumor growth inhibition, accompanied by tumor immune cell infiltration in the gastric tumor model.

Challenges and perspectives for immunotherapy in oesophageal cancer: A look to the future (Review)

Oesophageal cancer is one of the most aggressive malignancies with limited treatment options, thus resulting in a high morbidity and mortality. With 5‑year survival rates of only 5‑10%, oesophageal cancer holds a dismal prognosis for patients. In order to improve overall survival, the early diagnosis and tools for patient stratification for personalized treatment are urgent needs. A minority of oesophageal cancers belong to the spectrum of Lynch syndrome‑associated cancers and are characterized by microsatellite instability (MSI). Microsatellite instability is a consequence of defective mismatch repair protein functions and it has been well characterized in other gastrointestinal tumours, such as colorectal and gastric cancer. In the latter, high levels of MSI are associated with a better prognosis and with an increased benefit to immune‑based therapies. Therefore, similar therapeutic approaches could offer an opportunity of treatment for oesophageal cancer patients with MSI. Apart from immune checkpoint inhibitors, other immunotherapies such as adoptive T‑cell transfer, peptide vaccine and oncolytic viruses are under investigation in oesophageal cancer patients. In the present review, the rationale and current knowledge about immunotherapies in oesophageal cancer are summarised.

Targeting FAPα-expressing tumor-associated mesenchymal stromal cells inhibits triple-negative breast cancer pulmonary metastasis

Tumor metastasis is the main cause of death in patients with triple-negative breast cancer (TNBC). Bone marrow-derived mesenchymal stem cells (BM-MSCs) have tropism towards tumor tissues, and can be converted into tumor-associated mesenchymal stromal cells (TA-MSCs) to facilitate TNBC metastasis through interactions with tumor-associated macrophages (TAMs). However, the underlying molecular mechanisms are complex and unclear, and effective strategies to suppress tumor metastasis via eliminating TA-MSCs are still lacking. Here, we demonstrate that fibroblast activation protein alpha (FAPα) was overexpressed in TA-MSCs, which prompts TA-MSCs to secrete multiple C-C motif chemokine ligands, promoting C-C motif chemokine receptor 2 (CCR2)⁺ TAM recruitment and facilitating TAM polarization into the M2 phenotype, thereby promoting TNBC pulmonary metastasis. Z-GP-DAVLBH, an FAPα-activated vinblastine prodrug, induces FAPα⁺ TA-MSC apoptosis, which significantly suppresses CCR2⁺ TAM recruitment and polarization, thus inhibiting pulmonary metastasis of orthotopic TNBC cell-derived xenografts and patient-derived xenografts. This study provides insight into an important role of FAPα in mediating TA-MSC-induced TNBC metastasis and provides compelling evidence that targeting TA-MSCs with an FAPα-activated prodrug is a promising strategy for suppressing TNBC metastasis.

Immune-related gene data-based molecular subtyping related to the prognosis of breast cancer patients

Background

Breast cancer (BC), which is the most common malignant tumor in females, is associated with increasing morbidity and mortality. Effective treatments include surgery, chemotherapy, radiotherapy, endocrinotherapy and molecular-targeted therapy. With the development of molecular biology, immunology and pharmacogenomics, an increasing amount of evidence has shown that the infiltration of immune cells into the tumor microenvironment, coupled with the immune phenotype of tumor cells, will significantly affect tumor development and malignancy. Consequently, immunotherapy has become a promising treatment for BC prevention and as a modality that can influence patient prognosis.

Methods

In this study, samples collected from The Cancer Genome Atlas (TCGA) and ImmPort databases were analyzed to investigate specific immune-related genes that affect the prognosis of BC patients. In all, 64 immune-related genes related to prognosis were screened, and the 17 most representative genes were finally selected to establish the prognostic prediction model of BC (the RiskScore model) using the Lasso and StepAIC methods. By establishing a training set and a test set, the efficiency, accuracy and stability of the model in predicting and classifying the prognosis of patients were evaluated. Finally, the 17 immune-related genes were functionally annotated, and GO and KEGG signal pathway enrichment analyses were performed.

Results

We found that these 17 genes were enriched in numerous BC- and immune microenvironment-related pathways. The relationship between the RiskScore and the clinical characteristics of the sample and signaling pathways was also analyzed.

Conclusions

Our findings indicate that the prognostic prediction model based on the expression profiles of 17 immune-related genes has demonstrated high predictive accuracy and stability in identifying immune features, which can guide clinicians in the diagnosis and prognostic prediction of BC patients with different immunophenotypes.

Electronic supplementary material

The online version of this article (10.1007/s12282-020-01191-z) contains supplementary material, which is available to authorized users.

Solanine Inhibits Immune Escape Mediated by Hepatoma Treg Cells via the TGFβ/Smad Signaling Pathway

Objective

To observe the inhibitory effect of solanine on regulatory T cells (Treg) in transplanted hepatoma mice and to study the mechanism of solanine inhibiting tumor growth.

Methods

The levels of Treg cells and IL-2, IL-10, and TGFβ in the blood of patients with liver cancer were detected by flow cytometry and ELISA, respectively. A mouse hepatocellular carcinoma (HCC) graft model was established and randomly divided into four groups: control group, solanine group, TGFβ inhibitor group (SB-431542), and solanine ⁺TGFβ inhibitor combined group. Tumor volume of each group was recorded, tumor inhibition rate was calculated, and tumor metastasis was counted. The proportion of CD4⁺CD25⁺Foxp3⁺ Treg in transplanted tumor tissues was detected by flow cytometry. The expression levels of Foxp3 and TGFβ in transplanted tumor tissues were detected by quantitative fluorescence PCR.

Results

Compared with healthy people, Treg cells and IL-2, IL-10, and TGFβ contents in peripheral blood of liver cancer patients were increased. The results of the transplanted tumor model in mice showed that the tumor volume of the transplanted mice in the solanine group and the TGFβ inhibitor mice was reduced compared with the control group. The combined group had the smallest tumor volume. The proportion of CD4⁺CD25⁺Foxp3⁺ Treg in the transplanted tumor tissues of mice in the solanine treatment group was significantly lower than that in the control group. The expressions of Foxp3 and TGFβ in the transplanted tumor tissues of mice in the solanine group were significantly lower than those in the control group.

Conclusion

Solanine may enhance the antitumor immune response by downregulating the proportion of CD4⁺CD25⁺ Treg and the expression of Foxp3 and TGFβ in tumor tissues.

Interferon-γ signaling is associated with BRCA1 loss-of-function mutations in high grade serous ovarian cancer

Loss-of-function mutations of the breast cancer type 1 susceptibility protein (BRCA1) are associated with breast (BC) and ovarian cancer (OC). To identify gene signatures regulated by epigenetic mechanisms in OC cells carrying BRCA1 mutations, we assessed cellular responses to epigenome modifiers and performed genome-wide RNA- and chromatin immunoprecipitation-sequencing in isogenic OC cells UWB1.289 (carrying a BRCA1 mutation, BRCA1-null) and UWB1.289 transduced with wild-type BRCA1 (BRCA1+). Increased sensitivity to histone deacetylase inhibitors (HDACi) was observed in BRCA1-null vs. BRCA1+ cells. Gene expression profiles of BRCA1-null vs. BRCA1+ cells and treated with HDACi were integrated with chromatin mapping of histone H3 lysine 9 or 27 acetylation. Gene networks activated in BRCA1-null vs. BRCA1 + OC cells related to cellular movement, cellular development, cellular growth and proliferation, and activated upstream regulators included TGFβ1, TNF, and IFN-γ. The IFN-γ pathway was altered by HDACi in BRCA1+ vs. BRCA1-null cells, and in BRCA1-mutated/or low vs. BRCA1-normal OC tumors profiled in the TCGA. Key IFN-γ-induced genes upregulated at baseline in BRCA1-null vs. BRCA1+OC and BC cells included CXCL10, CXCL11, and IFI16. Increased localization of STAT1 in the promoters of these genes occurred in BRCA1-null OC cells, resulting in diminished responses to IFN-γ or to STAT1 knockdown. The IFN-γ signature was associated with improved survival among OC patients profiled in the TCGA. In all, our results support that changes affecting IFN-γ responses are associated with inactivating BRCA1 mutations in OC. This signature may contribute to altered responses to anti-tumor immunity in BRCA1-mutated cells or tumors.

Programmed Cell Death Ligand 1 in Breast Cancer: Technical Aspects, Prognostic Implications, and Predictive Value

In the light of recent advances in the immunotherapy field for breast cancer (BC) treatment, especially in the triple-negative subtype, the identification of reliable biomarkers capable of improving patient selection is paramount, because only a portion of patients seem to derive benefit from this appealing treatment strategy. In this context, the role of programmed cell death ligand 1 (PD-L1) as a potential prognostic and/or predictive biomarker has been intensively explored, with controversial results. The aim of the present review is to collect available evidence on the biological relevance and clinical utility of PD-L1 expression in BC, with particular emphasis on technical aspects, prognostic implications, and predictive value of this promising biomarker. IMPLICATIONS FOR PRACTICE: In the light of the promising results coming from trials of immune checkpoint inhibitors for breast cancer treatment, the potential predictive and/or prognostic role of programmed cell death ligand 1 (PD-L1) in breast cancer has gained increasing interest. This review provides clinicians with an overview of the available clinical evidence regarding PD-L1 as a biomarker in breast cancer, focusing on both data with a possible direct impact on clinic and methodological pitfalls that need to be addressed in order to optimize PD-L1 implementation as a clinically useful tool for breast cancer management.

IDO expression in breast cancer: an assessment of 281 primary and metastatic cases with comparison to PD-L1

The immune inhibitory enzyme indoleamine 2,3-dioxygenase (IDO) has been associated with immune evasion in numerous malignancies and may mark these cancers as susceptible to anti-IDO therapies. We herein address IDO expression in breast cancers, examine the relationship between IDO and PD-L1, and investigate IDO fidelity across breast cancer primaries and metastases. IDO and PD-L1 expression was assessed in tissue microarrays containing 242 invasive primary breast cancers, 20 nodal metastases, and 19 distant metastases. IDO and PD-L1 were scored by extent in the tumor cells and immune infiltrate. Tumor IDO staining was seen in 14% of primaries including 38% of triple-negative cancers. IDO immune cell staining was seen in 14% of primaries and 29% of triple-negative cancers. Tumoral IDO and PD-L1 co-expression was seen in 8% of primaries, including 70% of tumoral PD-L1-positive cases. Immune IDO and PD-L1 co-expression was identified in 14% of primaries, including 48% of immune PD-L1-positive cases. Tumoral and immune cell IDO was conserved in 94% of matched primary/metastasis. In summary, IDO expression is common among high-grade, triple-negative breast cancers and is frequently associated with PD-L1 co-expression, suggesting that IDO might be a mechanism of anti-PD-1/PD-L1 immunotherapy resistance and that dual therapy may be of utility. Tumoral and immune cell IDO expression shows fidelity between primary and metastatic sites in treatment-naïve cancers, arguing against IDO as an independent driver for metastatic spread. Clinical trials are needed to assess the efficacy of IDO inhibition relative to IDO expression, as well as its possible role in combination with anti-PD-1/PD-L1 immunotherapy.

Complete Clinical Remission of Stage IV Triple-Negative Breast Cancer Lung Metastasis Administering Low-Dose Immune Checkpoint Blockade in Combination With Hyperthermia and Interleukin-2

The prognosis of triple-negative breast cancer with metastases after chemotherapy remains dismal. We report the case of a 50-year-old female with first disease recurrence at the axillary lymph node and, later on, bilateral pulmonary metastases with severe shortness of breath. The patient received low-dose immune checkpoint blockade (concurrent nivolumab and ipilimumab) weekly over 3 weeks with regional hyperthermia 3 times a week, followed by systemic fever-range hyperthermia induced by interleukin-2 for 5 days. She went into complete remission of her pulmonary metastases with transient WHO I-II diarrhea and skin rash. The patient remained alive for 27 months after the start of treatment, with recurrence of metastases as a sternal mass, and up to 3 cm pleural metastases. This exceptional response should instigate further research efforts with this protocol, which consists only of approved drugs and treatments.

Preoperative lymphocyte-to-monocyte ratio predicts breast cancer outcome: A meta-analysis

AIM

To assess the prognostic value of the preoperative lymphocyte-to-monocyte ratio (LMR) in patients with breast cancer (BC).

METHODS

Relevant studies were systematically retrieved from the online Cochrane, MEDLINE, EMBASE and CNKI databases published until February 2018. The end points were overall survival (OS), disease-free survival (DFS), and clinicopathological parameters. Meta-analysis was performed using hazard ratios (HRs) or odds ratios (ORs) and their 95% confidence intervals (CIs) as effect measures.

RESULTS

Ten studies with 5667 individuals were included. The synthesized analysis demonstrated that that low LMR was significantly associated with poor OS (HR: 0.65, 95% CI: 0.47-0.90, p = .009) and DFS (HR: 0.60, 95% CI: 0.49-0.74, p < .001). Subgroup analyses revealed that the negative prognostic impact of low LMR on OS outcomes remained substantial in Asian populations, triple-negative patients, and patients with non-metastatic and mixed stage. However, low LMR was not significantly related to clinicopathological features.

CONCLUSION

The preoperative LMR might be a predictive factor of poor prognosis for BC patients.

Mismatch repair status and PD-L1 expression in clear cell carcinomas of the ovary and endometrium

Clear cell carcinoma represents a distinct histologic type of müllerian carcinoma that is resistant to conventional chemotherapy. Expression of programmed cell death ligand (PD-L1) has been associated with immune evasion in numerous tumor types and may be used to identify patients who will benefit from targeted immunotherapy, particularly in the setting of mismatch repair defects. We evaluated PD-L1 expression in 23 ovarian clear cell carcinomas and 21 endometrial clear cell carcinomas, and correlated expression with mismatch repair status. Tumor PD-L1 staining was seen in 43% of ovarian tumors and 76% of endometrial tumors, including 71% of cases (67% of ovarian and 75% of endometrial) with mismatch repair defects. Extensive tumoral staining (>50%) was seen in only one case (an endometrial case with MSH6 loss). However, tumoral PD-L1 expression remained common in mismatch repair-intact tumors and mismatch repair status was not significantly correlated with PD-L1 expression. The increased incidence of PD-L1 positivity in tumor cells (P=0.04) in endometrial vs ovarian clear cell carcinomas suggests differences in the tumor microenvironment of these histologically and molecularly similar tumors that may inform treatment options. These results suggest that clear cell histology may be a useful susceptibility marker for immunotherapy targeting the PD-1/PD-L1 axis irrespective of mismatch repair status, particularly in endometrial carcinomas.

Gene regulatory pattern analysis reveals essential role of core transcriptional factors' activation in triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype. Genome-scale molecular characteristics and regulatory mechanisms that distinguish TNBC from other subtypes remain incompletely characterized.

Results

By combining gene expression analysis and PANDA network, we defined three different TF regulatory patterns. A core TNBC-Specific TF Activation Driven Pattern (TNBCac) was specifically identified in TNBC by computational analysis. The essentialness of core TFs (ZEB1, MZF1, SOX10) in TNBC was highlighted and validated by cell proliferation analysis. Furthermore, 13 out of 35 co-targeted genes were also validated to be targeted by ZEB1, MZF1 and SOX10 in TNBC cell lines by real-time quantitative PCR. In three breast cancer cohorts, non-TNBC patients could be stratified into two subgroups by the 35 co-targeted genes along with 5 TFs, and the subgroup that more resembled TNBC had a worse prognosis.

Methods

We constructed gene regulatory networks in breast cancer by Passing Attributes between Networks for Data Assimilation (PANDA). Co-regulatory modules were specifically identified in TNBC by computational analysis, while the essentialness of core translational factors (TF) in TNBC was highlighted and validated by in vitro experiments. Prognostic effects of different factors were measured by Log-rank test and displayed by Kaplan-Meier plots.

Conclusions

We identified a core co-regulatory module specifically existing in TNBC, which enabled subtype re-classification and provided a biologically feasible view of breast cancer.

MicroRNA-519a-3p mediates apoptosis resistance in breast cancer cells and their escape from recognition by natural killer cells

Aggressive breast cancer is associated with poor patient outcome and characterized by the development of tumor cell variants that are able to escape from control of the immune system or are resistant to targeted therapies. The complex molecular mechanisms leading to immune escape and therapy resistance are incompletely understood. We have previously shown that high miR-519a-3p levels are associated with poor survival in breast cancer. Here, we demonstrate that miR-519a-3p confers resistance to apoptosis induced by TRAIL, FasL and granzyme B/perforin by interfering with apoptosis signaling in breast cancer cells. MiR-519a-3p diminished the expression of its direct target genes for TRAIL-R2 (TNFRSF10B) and for caspase-8 (CASP8) and its indirect target gene for caspase-7 (CASP7), resulting in reduced sensitivity and tumor cell apoptosis in response to apoptotic stimuli. Furthermore, miR-519a-3p impaired tumor cell killing by natural killer (NK) cells via downregulation of the NKG2D ligands ULBP2 and MICA on the surface of tumor cells that are crucial for the recognition of these tumor cells by NK cells. We determined that miR-519a-3p was overexpressed in more aggressive mutant TP53 breast cancer that was associated with poor survival. Furthermore, low levels of TRAIL-R2, caspase-7 and caspase-8 correlated with poor survival, suggesting that the inhibitory effect of miR-519a-3p on TRAIL-R2 and caspases may have direct clinical relevance in lowering patient’s prognosis. In conclusion, we demonstrate that miR-519a-3p is a critical factor in mediating resistance toward cancer cell apoptosis and impairing tumor cell recognition by NK cells. This joint regulation of apoptosis and immune cell recognition through miR-519a-3p supports the hypothesis that miRNAs are key regulators of cancer cell fate, facilitating cancer progression and evasion from immunosurveillance at multiple and interconnected levels.

PD-L1 Expression in Mismatch Repair-deficient Endometrial Carcinomas, Including Lynch Syndrome-associated and MLH1 Promoter Hypermethylated Tumors

Mismatch repair (MMR)-deficient endometrial carcinomas (ECs) bearing Lynch syndrome (LS)-associated germline mutations or sporadic MLH1 promoter hypermethylation (MLH1hm) are highly immunogenic and may represent excellent candidates for therapies targeting the programmed cell death (PD)/programmed cell death ligand-1 (PD-L1) immune checkpoint pathway. This study evaluates PD-L1 expression in MMR-deficient ECs including LS-associated and MLH1hm cases, in comparison with MMR-intact tumors. Immunohistochemistry for PD-L1/CD274 was performed on 38 MMR-deficient and 29 MMR-intact ECs. Staining was scored in the tumor and the peritumoral immune compartment. The majority of MMR-deficient tumors were PD-L1 positive (53%) in at least a subset of tumor cells. LS-associated tumors were more likely to be PD-L1 positive relative to MLH1hm tumors (70% vs. 33%, P=0.05). Only 10% of MMR-intact ECs demonstrated any tumoral PD-L1 expression; this was significantly lower than was observed in MMR-deficient tumors (P=0.0005). When reviewed by histologic grade, PD-L1 expression remained highest in LS-associated ECs followed by MLH1hm and MMR-intact carcinomas, respectively. The MMR immunohistochemical pattern most uniformly associated with PD-L1 expression was MSH6 loss. Immune PD-L1 expression was seen in 100% of MMR-deficient and 66% of MMR-intact cases. This study represents the first to characterize differences in PD-L1 expression between LS-associated and MLH1hm endometrial cancers. It demonstrates that tumoral PD-L1 expression is more common in LS-associated endometrial cancers relative to MLH1hm and MMR-intact tumors, although sporadic cancers often show PD-L1 positive immune staining. These data suggest that MMR deficiency may be a better predictor of response to PD-1/PD-L1 inhibitor therapy than tumor grade in EC, and that potential benefit may vary based on the molecular mechanism of MMR defects.

Mechanism of immune evasion in breast cancer

Breast cancer (BC) is the most common malignant tumor among women, with high morbidity and mortality. Its onset, development, metastasis, and prognosis vary among individuals due to the interactions between tumors and host immunity. Many diverse mechanisms have been associated with BC, with immune evasion being the most widely studied to date. Tumor cells can escape from the body’s immune response, which targets abnormal components and foreign bodies, using different approaches including modification of surface antigens and modulation of the surrounding environment. In this review, we summarize the mechanisms and factors that impact the immunoediting process and analyze their functions in detail.

Pattern of metastatic spread and subcategories of breast cancer

PURPOSE

The development of metastases is the most aggressive attribute of breast cancer. In this retrospective multicenter study, we evaluated if and how the different pathological breast cancer subtypes influence the spreading of tumor cells, the development of metastasis and the survival of breast cancer patients.

METHODS

This retrospective German multicenter study is based on the BRENDA collective including 9625 breast cancer patients treated in the adjuvant setting. We used the χ ² tests for the analysis of the categorical variables between groups of patients with different sites of metastasis. Survival distributions and median survival times were estimated using the Kaplan-Meier product-limit method. The log-rank test was applied to compare survival rates. The Cox proportional hazards model was used to estimate the hazard ratio and confidence intervals.

RESULTS

886 women developed metastases during a time interval of 53 months after primary diagnosis. Luminal A tumor patients were more likely to get bone metastases than lung, liver or CNS metastases. Patients with a triple-negative subtype were, however, the least affected by metastasis in the skeleton. They were most likely to develop visceral metastases. Location, numbers of metastases herein and the subtype influenced the overall survival (OAS). Altogether, the best OAS was found in patients with the luminal A subtype, the worst in patients with the triple-negative subtype.

CONCLUSIONS

Knowledge of the typical metastatic pattern of the subtypes of breast cancer will help to personalize therapeutic options and follow-up examinations of cancer patients.

A-Disintegrin and Metalloproteinase (ADAM) 17 Enzymatically Degrades Interferon-gamma

Interferon-gamma (IFN-γ) is a pleiotropic cytokine that exerts anti-tumor and anti-osteoclastogenic effects. Although transcriptional and post-transcriptional regulation of IFN-γ is well understood, subsequent modifications of secreted IFN-γ are not fully elucidated. Previous research indicates that some cancer cells escape immune surveillance and metastasize into bone tissue by inducing osteoclastic bone resorption. Peptidases of the a-disintegrin and metalloproteinase (ADAM) family are implicated in cancer cell proliferation and tumor progression. We hypothesized that the ADAM enzymes expressed by cancer cells degrades IFN-γ and attenuates IFN-γ-mediated anti-tumorigenic and anti-osteoclastogenic effects. Recombinant ADAM17 degraded IFN-γ into small fragments. The addition of ADAM17 to the culture supernatant of stimulated mouse splenocytes decreased IFN-γ concentration. However, ADAM17 inhibition in the stimulated mouse T-cells prevented IFN-γ degradation. ADAM17-expressing human breast cancer cell lines MCF-7 and MDA-MB-453 also degraded recombinant IFN-γ, but this was attenuated by ADAM17 inhibition. Degraded IFN-γ lost the functionality including the inhibititory effect on osteoclastogenesis. This is the first study to demonstrate the extracellular proteolytic degradation of IFN-γ by ADAM17. These results suggest that ADAM17-mediated degradation of IFN-γ may block the anti-tumorigenic and anti-osteoclastogenic effects of IFN-γ. ADAM17 inhibition may be useful for the treatment of attenuated cancer immune surveillance and/or bone metastases.

Triple negative breast cancer chemosensitivity and chemoresistance: current advances in biomarkers indentification

INTRODUCTION

Triple negative breast cancer (TNBC) is a heterogeneous clinicopathological entity constituting approximately 15 - 20% of all breast cancer (BC) patients. It shows high recurrence rate and poor prognosis. At this juncture, because of the lack of specific targeted therapies available and the development in patients of resistance to some therapeutic agents, clinical and translational settings have gained importance over the past decades.

AREAS COVERED

The development of novel, safe and effective alternatives for the treatment of TNBC are in high demand. Therefore, this review aims to summarize the state of the art of TNBC, its current therapies and potential therapeutic targets. In particular, focus is put on recent advances regarding the identification of emerging biomarkers as prognostic and/or predictive markers, including surrogate markers for molecular tumor subtyping and identifying potential responders to new therapies.

EXPERT OPINION

Effective development of informative markers could constitute an important armamentarium tool for identifying appropriate therapies to challenge the aggressiveness of TNBC.

The Peripheral Blood Neutrophil-To-Lymphocyte Ratio Is Superior to the Lymphocyte-To-Monocyte Ratio for Predicting the Long-Term Survival of Triple-Negative Breast Cancer Patients

Purpose

The peripheral hematologic parameters of patients can be prognostic for many malignant tumors, including breast cancer, although their value has not been investigated among the different molecular subtypes of breast cancer. The purpose of this study was to examine the prognostic significance of the neutrophil-to-lymphocyte ratio (NLR) and the lymphocyte-to-monocyte ratio (LMR) in different molecular subtypes of breast cancer.

Methods

A retrospective cohort of 1570 operable breast cancer patients was recruited between January 2000 and December 2010. The counts of peripheral neutrophils, lymphocytes, monocytes and platelets were collected and applied to calculate the NLR and the LMR. Univariate and multivariate Cox proportional hazard analyses were used to assess the relationship of the NLR and the LMR with disease-free survival (DFS) and overall survival (OS) in all patients and triple negative breast cancer (TNBC) patients.

Results

Univariate analysis revealed that lower NLR (≤2.0) and higher LMR (>4.8) were significantly associated with superior DFS in all patients (NLR, P = 0.005; LMR, P = 0.041) and in TNBC patients (NLR, p = 0.007; LMR, P = 0.011). However, multivariate analysis revealed that only lower NLR was a significant independent predictor of superior DFS and OS in all breast cancer patients (DFS, HR = 1.50 95% CI: 1.14–1.97, P = 0.004; OS, HR = 1.63, 95% CI: 1.07–2.49, P = 0.022) and in TNBC patients (DFS, HR = 2.58, 95% CI: 1.23–5.42, P = 0.012; OS, HR = 3.05, 95% CI: 1.08–8.61, P = 0.035). Both univariate and multivariate analysis revealed that neither the NLR nor the LMR significantly predicted DFS and OS among the patients with other molecular subtypes of breast cancer.

Conclusions

A higher pretreatment peripheral NLR significantly and independently indicated a poor prognosis for breast cancer and TNBC, and this measurement exhibited greater prognostic value than a lower LMR. The NLR was not a prognostic factor for other breast cancer subtypes.

The PD-1/B7-H1 pathway modulates the natural killer cells versus mouse glioma stem cells

PURPOSE

Glioblastoma multiforme (GBM) is the most malignant primary type of brain tumor in adults. There has been increased focus on the immunotherapies to treat GBM patients, the therapeutic value of natural killer (NK) cells is still unknown. Programmed death-1 (PD-1) is a major immunological checkpoint that can negatively regulate the T-cell-mediated immune response. We tested the combination of the inhibiting the PD-1/B7H1 pathway with a NK-cell mediated immune response in an orthotopic mouse model of GBM.

METHODS AND MATERIALS

Mouse glioma stem cells (GL261GSCs) and mouse NK cells were isolated and identified. A lactate dehydrogenase (LDH) assay was perfomed to detect the cytotoxicity of NK cells against GL261GSCs. GL261GSCs were intracranially implanted into mice, and the mice were stratified into 3 treatment groups: 1) control, 2) NK cells treatment, and 3) PD-1 inhibited NK cells treatment group. Overall survival was quantified, and animal magnetic resonance imaging (MRI) was performed to determine tumor growth. The brains were harvested after the mice were euthanized, and immunohistochemistry against CD45 and PCNA was performed.

RESULTS

The mouse NK cells were identified as 90% CD3- NK1.1+CD335+ by flow cytometric analysis. In the LDH assay, the ratios of the damaged GL261GSCs, with the E:T ratios of 2.5:1, 5:1, and 10:1, were as follows: 1) non-inhibited group: 7.42%, 11.31%, and 15.1%, 2) B7H1 inhibited group: 14.75%, 18.25% and 29.1%, 3) PD-1 inhibited group: 15.53%, 19.21% and 29.93%, 4) double inhibited group: 33.24%, 42.86% and 54.91%. In the in vivo experiments, the mice in the PD-1 inhibited NK cells treatment group and IL-2-stimulated-NK cells treatment group displayed a slowest tumor growth (F = 308.5, P<0.01) and a slower tumor growth compared with control group (F = 118.9, P<0.01), respectively. The median survival of the mice in the three groups were as follows: 1) conrol group: 29 days, 2) NK cells treatment group: 35 days (P = 0.0012), 3) PD-1 inhibited NK cells treatment group: 44 days (P = 0.0024). Immunologic data of PCNA-positive cell ratios and CD45-positive cell ratios of the tumor specimens in the three groups were as follows: 1) control group: 65.72% (PCNA) and 0.92% (CD45), 2) NK treatment group: 27.66% (PCNA) and 13.46% (CD45), and 3) PD-1 inhibited NK cells treatment group: 13.66% (PCNA) and 23.66% (CD45) (P<0.001).

CONCLUSION

The results demonstrated that blockade of PD-1/B7H1 pathway could promote mouse NK cells to kill the GL261GSCs, and the PD-1-inhibited NK cells could be a feasible immune therapeutic approach against GBM.

The latest progress in research on triple negative breast cancer (TNBC): risk factors, possible therapeutic targets and prognostic markers

Triple negative breast cancer (TNBC) is one type of breast cancer (BC), which is defined as negative for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (Her2). Its origins and development seem to be elusive. And for now, drugs like tamoxifen or trastuzumab which specifically apply to ER, PR or Her2 positive BC seem unforeseeable in TNBC clinical treatment. Due to its extreme malignancy, high recurrence rate and poor prognosis, a lot of work on the research of TNBC is needed. This review aims to summarize the latest findings in TNBC in risk factors, possible therapeutic targets and possible prognostic makers.

Prognostic value of preoperative inflammatory markers in Chinese patients with breast cancer

Cancer-associated inflammation is a key determinant of disease progression and survival in most cancers. The aim of our study was to assess the predictive value of preoperative inflammatory markers, such as the neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio, red cell distribution width (RDW), and mean platelet volume, for survival in breast cancer patients. In total, 608 breast cancer patients operated on between January 2009 and December 2011 were included in this observational study. The association between preoperative inflammatory markers and survival outcomes was analyzed. Patients with high NLR (>2.57) or high RDW (>13.45%) showed a significantly lower overall survival rate than those with lower NLR (≤2.57) or lower RDW (≤13.45%). NLR and RDW, along with node stage and molecular subtypes, were independent prognostic factors. There was a significant survival difference according to NLR in the luminal A and triple-negative subtypes (93.3% versus 99.3%, P=0.001; 68.8% versus 95.1%, P=0.000, respectively). The triple-negative subtype was the only subtype in which higher RDW patients showed significantly poor prognosis (81.3% versus 95.5%, P=0.025). Pre-operation NLR and RDW is a convenient, easily measured prognostic indicator for patients with breast cancer, especially in patients with the triple-negative subtype.