The Immune Microenvironment in Hormone Receptor-Positive Breast Cancer Before and After Preoperative Chemotherapy

Male breast cancer differs from female breast cancer in molecular features that affect prognoses and drug responses

BACKGROUND

Male breast cancer (MBC) is a rare malignancy with a worse prognosis than female breast cancer (FBC). Current MBC treatment strategies are based on those for FBC. However, molecular differences between MBC and FBC with respect to prognosis and drug responses remain unclear.

METHODS

After controlling for confounding factors with propensity score matching (PSM), differences between MBC and FBC were comprehensively analyzed using many types of data: survival, immune microenvironments, sex hormone responses, drug sensitivity, transcriptomes, genomes, epigenomes, and proteomes.

RESULTS

Overall survival (OS) and cancer-specific survival (CSS) were both worse for MBC than for FBC. Differentially expressed mRNAs were enriched in numerous cancer-related functions and pathways, with SPAG16 and STOX1 being as the most important prognosis-related mRNAs for MBC. Competing endogenous RNA (ceRNA) and transcription factor (TF)-mRNA regulatory networks contain potential prognostic genes. Nine genes had higher mutation frequencies in MBC than in FBC. MBC shows a comparatively poor response to immunotherapy, with five proteins that promote breast cancer progression being highly expressed in MBC. MBC may be more responsive than FBC to estrogen. We detected six United States Food and Drug Administration (FDA)-approved therapeutic target genes as being differentially expressed between MBC and FBC.

CONCLUSION

The poor prognosis of MBC compared to FBC is due to numerous molecular differences and resulting drug responses.

A review concerning the breast cancer-related tumour microenvironment

Breast cancer (BC) is currently the most common malignant tumour in women and one of the leading causes of their death around the world. New and increasingly personalised diagnostic and therapeutic tools have been introduced over the last few decades, along with significant advances regarding the study and knowledge related to BC. The tumour microenvironment (TME) refers to the tumour cell-associated cellular and molecular environment which can influence conditions affecting tumour development and progression. The TME is composed of immune cells, stromal cells, extracellular matrix (ECM) and signalling molecules secreted by these different cell types. Ever deeper understanding of TME composition changes during tumour development and progression will enable new and more innovative therapeutic strategies to become developed for targeting tumours during specific stages of its evolution. This review summarises the role of BC-related TME components and their influence on tumour progression and the development of resistance to therapy. In addition, an account on the modifications in BC-related TME components associated with therapy is given, and the completed or ongoing clinical trials related to this topic are presented.

Estrogen receptor regulation of the immune microenvironment in breast cancer

Breast cancer (BCa) is the most common cancer in women and the estrogen receptor (ER)+ subtype is increasing in incidence. There are numerous therapy options available for patients that target the ER, however issues such as innate and acquired treatment resistance, and treatment related side effects justify research into alternative therapeutic options for these patients. Patients of many solid tumour types have benefitted from immunotherapy, however response rates have been generally low in ER+ BCa. We summarise the recent work assessing CDK4/6 inhibitors for ER+ BCa and how they have been shown to prime anti-tumour immune cells and achieve impressive results in preclinical models. A great example of how the immune system might be activated against ER+ BCa. We review the role of estrogen signalling in immune cells, and explore recent data highlighting the hormonal regulation of the immune microenvironment of normal breast, BCa and immune disorders. As recent data has indicated that macrophages are particularly susceptible to estrogen signalling, we highlight macrophage phagocytosis as a key potential target for priming the tumour immune microenvironment. We challenge the generally accepted paradigm that ER+ BCa are "immune-cold" - advocating instead for research into therapies that could be used in combination with targeted therapies and/or immune checkpoint blockade to achieve durable antitumour responses in ER+ BCa.

Neoadjuvant chemotherapy-induced remodeling of human hormonal receptor-positive breast cancer revealed by single-cell RNA sequencing

Hormone receptor-positive breast cancer (HR+ BC) is known to be relatively insensitive to chemotherapy, and since chemotherapy has remained the major neoadjuvant therapy for HR+ BC, the undetermined mechanism of chemoresistance and how chemotherapy reshapes the immune microenvironment need to be explored by high-throughput technology. By using single-cell RNA sequencing and multiplexed immunofluorescence staining analysis of HR+ BC samples (paired pre- and post-neoadjuvant chemotherapy (NAC)), the levels of previously unrecognized immune cell subsets, including CD8+ T cells with pronounced expression of T-cell development (LMNA) and cytotoxicity (FGFBP2) markers, CD4+ T cells characterized by proliferation marker (ATP1B3) expression and macrophages characterized by CD52 expression, were found to be increased post-NAC, which were predictive of chemosensitivity and their antitumor function was also validated with in vitro experiments. In terms of immune checkpoint expression of CD8+ T cells, we found their changes were inconsistent post-NAC, that LAG3, VSIR were decreased, and PDCD1, HAVCR2, CTLA4, KLRC1 and BTLA were increased. In addition, we have identified novel genomic and transcriptional patterns of chemoresistant cancer cells, both innate and acquired, and have confirmed their prognostic value with TCGA cohorts. By shedding light on the ecosystem of HR+ BC reshaped by chemotherapy, our results uncover valuable candidates for predicting chemosensitivity and overcoming chemoresistance in HR+ BC.

Durvalumab and tremelimumab before surgery in patients with hormone receptor positive, HER2-negative stage II-III breast cancer

A clinical trial was conducted to assess the feasibility of enrolling patients with Stage II or III hormone receptor positive (HR+)/HER2-negative breast cancer to pre-operative dual PD-L1/CTLA-4 checkpoint inhibition administered prior to neoadjuvant chemotherapy (NACT). Eight eligible patients were treated with upfront durvalumab and tremelimumab for two cycles. Patients then received NACT prior to breast surgery. Seven patients had baseline and interval breast ultrasounds after combination immunotherapy and the responses were mixed: 3/7 patients experienced a ≥30% decrease in tumor volume, 3/7 a ≥30% increase, and 1 patient had stable disease. At the time of breast surgery, 1/8 patients had a pathologic complete response (pCR). The trial was stopped early after 3 of 8 patients experienced immunotherapy-related toxicity or suspected disease progression that prompted discontinuation or a delay in the administration of NACT. Two patients experienced grade 3 immune-related adverse events (1 with colitis, 1 with endocrinopathy). Analysis of the tumor microenvironment after combination immunotherapy did not show a significant change in immune cell subsets from baseline. There was limited benefit for dual checkpoint blockade administered prior to NACT in our study of 8 patients with HR+/HER2-negative breast cancer.

Clinical Relevance of Tumour-Infiltrating Immune Cells in HER2-Negative Breast Cancer Treated with Neoadjuvant Therapy

Currently, therapy response cannot be accurately predicted in HER2-negative breast cancer (BC). Measuring stromal tumour-infiltrating lymphocytes (sTILs) and mediators of the tumour microenvironment and characterizing tumour-infiltrating immune cells (TIICs) may improve treatment response in the neoadjuvant setting. Tumour tissue and peripheral blood samples were retrospectively collected from 118 patients, and sTILs were evaluated. Circulating exosomes and myeloid-derived suppressor cells were determined by flow cytometry. TIICs markers (CD4, CD8, CD20, CD1a, and CD68) were assessed immunohistochemically. High sTILs were significantly associated with pathological complete response (pCR; p = 0.048) and event-free survival (EFS; p = 0.027). High-CD68 cells were significantly associated with pCR in triple-negative (TN, p = 0.027) and high-CD1a cells with EFS in luminal-B (p = 0.012) BC. Cluster analyses of TIICs revealed two groups of tumours (C1 and C2) that had different immune patterns and clinical outcomes. An immunoscore based on clinicopathological variables was developed to identify high risk (C1) or low-risk (C2) patients. Additionally, cluster analyses revealed two groups of tumours for both luminal-B and TNBC. Our findings support the association of sTILs with pCR and show an immunological component in a subset of patients with HER2-negative BC. Our immunoscore may be useful for future escalation or de-escalation treatments.

MCM2 is involved in subtyping and tamoxifen resistance of ERα-positive breast cancer by acting as the downstream factor of ERα

Tamoxifen (TAM) resistance is finally developed in over 40% of patients with estrogen receptor α-positive breast cancer (ERα+ -BC), documenting that discovering new molecular subtype is needed to confer perception to the heterogeneity of ERα+ -BC. We obtained representative gene sets subtyping ERα+ -BC using gene set variation analysis (GSVA), non-negative matrix factorization (NMF), and COX regression methods on the basis of METABRIC, TCGA, and GEO databases. Furthermore, the risk score of ERα+ -BC subtyping was established using least absolute shrinkage and selection operator (LASSO) regression on the basis of genes in the representative gene sets, thereby generating the two subtypes of ERα+ -BC. We further found that minichromosome maintenance complex component 2 (MCM2) functioned as the hub gene subtyping ERα+ -BC using GO, KEGG, and MCODE. MCM2 expression was capable for specifically predicting 1-year overall survival (OS) of ERα+ -BC and correlated with T stage, AJCC stage, and tamoxifen (TAM) sensitivity of ERα+ -BC. The downregulation of MCM2 expression inhibited proliferation, migration, and invasion of TAM-resistant cells and promoted G0/G1 arrest. Altogether, tamoxifen resistance entails that MCM2 is a hub gene subtyping ERα+ -BC, providing a novel dimension for discovering a potential target of TAM-resistant BC.

Genomic and transcriptomic analysis of breast cancer identifies novel signatures associated with response to neoadjuvant chemotherapy

BACKGROUND

Neoadjuvant chemotherapy (NAC) has become a standard treatment strategy for breast cancer (BC). However, owing to the high heterogeneity of these tumors, it is unclear which patient population most likely benefit from NAC. Multi-omics offer an improved approach to uncovering genomic and transcriptomic changes before and after NAC in BC and to identifying molecular features associated with NAC sensitivity.

METHODS

We performed whole-exome and RNA sequencing on 233 samples (including matched pre- and post-treatment tumors) from 50 BC patients with rigorously defined responses to NAC and analyzed changes in the multi-omics landscape. Molecular features associated with NAC response were identified and validated in a larger internal, and two external validation cohorts, as well as in vitro experiments.

RESULTS

The most frequently altered genes were TP53, TTN, and MUC16 in both pre- and post-treatment tumors. In comparison with pre-treatment tumors, there was a significant decrease in C > A transversion mutations in post-treatment tumors (P = 0.020). NAC significantly decreased the mutation rate (P = 0.006) of the DNA repair pathway and gene expression levels (FDR = 0.007) in this pathway. NAC also significantly changed the expression level of immune checkpoint genes and the abundance of tumor-infiltrating immune and stroma cells, including B cells, activated dendritic cells, γδT cells, M2 macrophages and endothelial cells. Furthermore, there was a higher rate of C > T substitutions in NAC nonresponsive tumors than responsive ones, especially when the substitution site was flanked by C and G. Importantly, there was a unique amplified region at 8p11.23 (containing ADGRA2 and ADRB3) and a deleted region at 3p13 (harboring FOXP1) in NAC nonresponsive and responsive tumors, respectively. Particularly, the CDKAL1 missense variant P409L (p.Pro409Leu, c.1226C > T) decreased BC cell sensitivity to docetaxel, and ADGRA2 or ADRB3 gene amplifications were associated with worse NAC response and poor prognosis in BC patients.

CONCLUSIONS

Our study has revealed genomic and transcriptomic landscape changes following NAC in BC, and identified novel biomarkers (CDKAL1P409L, ADGRA2 and ADRB3) underlying chemotherapy resistance and poor prognosis, which could guide the development of personalized treatments for BC.

A comprehensive review on the applications of ferrite nanoparticles in the diagnosis and treatment of breast cancer

Various conventional treatments including endocrine therapy, radiotherapy, surgery, and chemotherapy have been used for several decades to treat breast cancer; however, these therapies exhibit various life-threatening and debilitating adverse effects in patients. Additionally, combination therapies are required for prompt action as well as to prevent drug resistance toward standard breast cancer medications. Ferrite nanoparticles (NPs) are increasingly gaining momentum for their application in the diagnosis and treatment of breast cancer. Spinel ferrites are particularly used against breast cancer and have shown in vitro and in vivo better efficacy as compared to conventional cancer therapies. Magnetic resonance imaging contrast agents, magnetic particle imaging tracers, cell separation, and immune assays are some aspects related to the diagnosis of breast cancer against which different ferrite NPs have been successfully evaluated. Moreover, citrate-coated nickel ferrite, Mg/Zn ferrites, poly amidoamine dendrimers, cobalt ferrites, graphene oxide cobalt ferrites, doxorubicin functionalized cobalt ferrites, chitosan-coated zinc ferrites, PEG-coated cobalt ferrite, and copper ferrite NPs have demonstrated antiproliferative action against different breast cancer cells. Oxaliplatin-loaded polydopamine/BSA-copper ferrites, functionalized cobalt and zinc ferrites of curcumin, oxaliplatin-copper ferrite NPs, tamoxifen/diosgenin encapsulated ZnO/Mn ferrites, and fabricated core-shell fibers of doxorubicin have been developed to increase the bioavailability and anti-proliferative effect and decrease the toxicity of anticancer drugs. These ferrite NPs showed an anticancer effect at different doses in the presence or absence of an external magnetic field. The present review covers the in-depth investigations of ferrite NPs for the diagnosis and management of breast cancer.

Immune characteristics and clinical significance of peripheral blood lymphocytes in breast cancer

BACKGROUND

In the context of breast cancer (BC), the correlation between lymphocytes and clinical outcomes, along with treatment response, has garnered attention. Despite this, few investigations have delved into the interplay among distinct peripheral blood lymphocyte (PBL) types, immune attributes, and their clinical implications within the BC landscape.

METHODS

The primary objective of this study was to scrutinize the baseline status of PBL subsets in patients with primary BC, track their dynamic changes throughout treatment, and ascertain their interrelation with prognosis. Flow cytometry was employed to analyse PBLs from a cohort of 74 BC patients.

RESULTS

Our analysis revealed that baseline levels of Treg and PD-L1 + T cells were lower in BC patients compared to the reference values. Notably, a disparity in baseline PD-L1 + T cell levels surfaced between patients who underwent adjuvant therapy and those subjected to neoadjuvant therapy (NAT). Furthermore, a meticulous evaluation of PBL subsets before and after treatment underscored discernible alterations in 324 + T cells and CD19 + CD32 + B cells over the course of therapy. Strikingly, heightened CD4 + T cell levels at baseline were linked to enhanced event-free survival (EFS) (p = 0.02) and a robust response to chemotherapy.

CONCLUSIONS

These results indicate that PBLs may serve as a significant marker to assess the immune status of BC patients, and therapy has the potential to modify patient immune profiles. In addition, peripheral blood CD4 + T cell levels may serve as promising biomarkers for diagnosis and prognosis in future studies of BC.

Immune cells within tertiary lymphoid structures are associated with progression-free survival in patients with locoregional recurrent breast cancer

INTRODUCTION

Locoregional recurrent breast cancers have a poor prognosis. Little is known about the prognostic impact of immune microenvironment, and tertiary lymphoid structures (TLSs) in particular have not been reported. Thus, we aimed to characterize the immune microenvironment in locoregional recurrent breast tumors and to investigate its relationship with prognosis.

METHODS

We retrospectively included 112 patients with locoregional recurrent breast cancer, and hematoxylin-eosin staining and immunohistochemical staining (CD3, CD4, CD8, CD19, CD38, and CD68) were performed on locoregional recurrent tumor samples. The association of immune cells and TLSs with progression-free survival (PFS) were analyzed by survival analysis.

RESULTS

We found more immune cells in the peritumor than stroma. After grouping according to estrogen receptor (ER) status, a low level of peritumoral CD3+ cells in ER+ subgroup (p = 0.015) and a low level of stromal CD68+ cells in ER- subgroup (p = 0.047) were both associated with longer PFS. TLSs were present in 68% of recurrent tumors, and CD68+ cells within TLSs were significantly associated with PFS as an independent prognostic factor (p = 0.035). TLSs and immune cells (CD3, CD38, and CD68) within TLSs were associated with longer PFS in ER- recurrent tumors (p = 0.044, p = 0.012, p = 0.050, p < 0.001, respectively), whereas CD38+ cells within TLSs were associated with shorter PFS in ER+ recurrent tumors (p = 0.037).

CONCLUSION

Our study proposes potential predictors for the clinical prognosis of patients with locoregional recurrent breast cancer, emphasizing the prognostic value of immune cells within TLSs, especially CD68+ cells.

LITAF Promotes Atherosclerotic Plaque Formation by Stimulating the NF-κB Inflammatory Pathway

OBJECTIVE

Lipopolysaccharide-induced tumor necrosis factor-α factor (LITAF) protein is a newly discovered inflammatory protein. This study aims to study the role of LITAF in the formation of atherosclerosis.

METHODS

A total of 10 C57BL/6J mice and 10 C57BL/6J mice with knockout of LITAF gene (C57BL/6J-LITAF-) were divided into two groups: the control group and the LITAF-/- group. The animals were accommodated for 16 weeks and then euthanized with their hearts and aortas isolated thereafter. Next, the roots of the mouse aorta were cryosectioned and stained with Oil Red O staining and immunohistochemical staining (CD68, α-SMA, and Masson), respectively. The area of Oil Red O staining and the proportion of positive expression after immunohistochemical staining were then compared between the control and LITAF-/- groups. At the same time, the blood of mice was collected for the extraction of proteins and RNA. The proteins and RNA were used to detect the expression of major molecules of the NF-κB inflammatory pathway in mice in the control group and the LITAF-/- group by Western blotting and RT-PCR.

RESULTS

Oil Red O staining of the aortic root sections of the mice in each group revealed that the area of atherosclerotic plaques in the LITAF-/- group was substantially lower than that in the control group (P<0.05). Moreover, immunohistochemical staining determined that the expression level of α-SMA and CD68 in the LITAF-/- group was significantly lower than that in the control group, whereas the results were reversed following Masson staining (P<0.05). The expression levels of P65 and caspase 3 were significantly lower in the LITAF-/- group than in the control group (P<0.05), whereas the expression level of IκB was higher in the LITAF-/- group.

CONCLUSION

LITAF might participate in the formation of atherosclerotic plaque through the NF-κB pathway and play a promoting role in the formation of atherosclerosis.

Intercellular Molecular Crosstalk Networks within Invasive and Immunosuppressive Tumor Microenvironment Subtypes Associated with Clinical Outcomes in Four Cancer Types

Heterogeneity is a critical basis for understanding how the tumor microenvironment (TME) contributes to tumor progression. However, an understanding of the specific characteristics and functions of TME subtypes (subTMEs) in the progression of cancer is required for further investigations into single-cell resolutions. Here, we analyzed single-cell RNA sequencing data of 250 clinical samples with more than 200,000 cells analyzed in each cancer datum. Based on the construction of an intercellular infiltration model and unsupervised clustering analysis, four, three, three, and four subTMEs were revealed in breast, colorectal, esophageal, and pancreatic cancer, respectively. Among the subTMEs, the immune-suppressive subTME (subTME-IS) and matrix remodeling with malignant cells subTME (subTME-MRM) were highly enriched in tumors, whereas the immune cell infiltration subTME (subTME-ICI) and precancerous state of epithelial cells subTME (subTME-PSE) were less in tumors, compared with paracancerous tissues. We detected and compared genes encoding cytokines, chemokines, cytotoxic mediators, PD1, and PD-L1. The results showed that these genes were specifically overexpressed in different cell types, and, compared with normal tissues, they were upregulated in tumor-derived cells. In addition, compared with other subTMEs, the expression levels of PDCD1 and TGFB1 were higher in subTME-IS. The Cox proportional risk regression model was further constructed to identify possible prognostic markers in each subTME across four cancer types. Cell-cell interaction analysis revealed the distinguishing features in molecular pairs among different subTMEs. Notably, ligand-receptor gene pairs, including COL1A1-SDC1, COL6A2-SDC1, COL6A3-SDC1, and COL4A1-ITGA2 between stromal and tumor cells, associated with tumor invasion phenotypes, poor patient prognoses, and tumor advanced progression, were revealed in subTME-MRM. C5AR1-RPS19, LGALS9-HAVCR2, and SPP1-PTGER4 between macrophages and CD8+ T cells, associated with CD8+ T-cell dysfunction, immunosuppressive status, and tumor advanced progression, were revealed in subTME-IS. The spatial co-location information of cellular and molecular interactions was further verified by spatial transcriptome data from colorectal cancer clinical samples. Overall, our study revealed the heterogeneity within the TME, highlighting the potential pro-invasion and pro-immunosuppressive functions and cellular infiltration characteristics of specific subTMEs, and also identified the key cellular and molecular interactions that might be associated with the survival, invasion, immune escape, and classification of cancer patients across four cancer types.

Estrogen receptor blockade and radiation therapy cooperate to enhance the response of immunologically cold ER+ breast cancer to immunotherapy

BACKGROUND

Most patients with estrogen receptor positive (ER+) breast cancer do not respond to immune checkpoint inhibition (ICI); the tumor microenvironment (TME) of these cancers is generally immunosuppressive and contains few tumor-infiltrating lymphocytes. Radiation therapy (RT) can increase tumor inflammation and infiltration by lymphocytes but does not improve responses to ICIs in these patients. This may result, in part, from additional effects of RT that suppress anti-tumor immunity, including increased tumor infiltration by myeloid-derived suppressor cells and regulatory T cells. We hypothesized that anti-estrogens, which are a standard of care for ER+ breast cancer, may ameliorate these detrimental effects of RT by reducing the recruitment/ activation of suppressive immune populations in the radiated TME, increasing anti-tumor immunity and responsiveness to ICIs.

METHODS

To interrogate the effect of the selective estrogen receptor downregulator, fulvestrant, on the irradiated TME in the absence of confounding growth inhibition by fulvestrant on tumor cells, we used the TC11 murine model of anti-estrogen resistant ER+ breast cancer. Tumors were orthotopically transplanted into immunocompetent syngeneic mice. Once tumors were established, we initiated treatment with fulvestrant or vehicle, followed by external beam RT one week later. We examined the number and activity of tumor infiltrating immune cells using flow cytometry, microscopy, transcript levels, and cytokine profiles. We tested whether fulvestrant improved tumor response and animal survival when added to the combination of RT and ICI.

RESULTS

Despite resistance of TC11 tumors to anti-estrogen therapy alone, fulvestrant slowed tumor regrowth following RT, and significantly altered multiple immune populations in the irradiated TME. Fulvestrant reduced the influx of Ly6C+Ly6G+ cells, increased markers of pro-inflammatory myeloid cells and activated T cells, and augmented the ratio of CD8+: FOXP3+ T cells. In contrast to the minimal effects of ICIs when co-treated with either fulvestrant or RT alone, combinatorial treatment with fulvestrant, RT and ICIs significantly reduced tumor growth and prolonged survival.

CONCLUSIONS

A combination of RT and fulvestrant can overcome the immunosuppressive TME in a preclinical model of ER+ breast cancer, enhancing the anti-tumor response and increasing the response to ICIs, even when growth of tumor cells is no longer estrogen sensitive.

Effect of liver metastasis on the efficacy of immune checkpoint inhibitors in cancer patients: a systemic review and meta-analysis

Liver metastasis is a frequent phenomenon in advanced tumor disease. Immune checkpoint inhibitors (ICIs) are a new class of therapeutics that can improve the prognosis of cancer patients. The purpose of this study is to elucidate the relationship between liver metastasis and survival outcomes of patients receiving ICIs treatment. We searched four main databases, including PubMed, EMBASE, Cochrane Library, and Web of Science. Overall survival (OS) and progression-free survival (PFS) were the survival outcomes of our concern. Hazard ratio (HR) with 95% confidence interval (CI) were used to evaluate the relationship between liver metastasis and OS/ PFS. Finally, 163 articles were included in the study. The pooled results showed that patients with liver metastasis receiving ICIs treatment had worse OS (HR=1.82, 95%CI:1.59-2.08) and PFS (HR=1.68, 95%CI:1.49-1.89) than patients without liver metastasis. The effect of liver metastasis on ICIs efficacy differed in different tumor types, and patients with urinary system tumors (renal cell carcinoma OS: HR=2.47, 95%CI:1.76-3.45; urothelial carcinoma OS: HR=2.37, 95%CI:2.03-2.76) had the worst prognosis, followed by patients with melanoma (OS: HR=2.04, 95%CI:1.68-2.49) or non-small cell lung cancer (OS: HR=1.81, 95%CI:1.72-1.91). ICIs efficacy in digestive system tumors (colorectal cancer OS: HR=1.35, 95%CI:1.07-1.71; gastric cancer/ esophagogastric cancer OS: HR=1.17, 95%CI:0.90-1.52) was less affected, and peritoneal metastasis and the number of metastases have a greater clinical significance than liver metastasis based on univariate data. For cancer patients receiving ICIs treatment, the occurrence of liver metastasis is associated with poor prognosis. Different cancer types and metastatic sites may hold a different prognostic effect on the efficacy of ICIs treatment in cancer patients.

Multiomics technologies for comprehensive tumor microenvironment analysis in triple-negative breast cancer under neoadjuvant chemotherapy

Triple-negative breast cancer (TNBC) is one of the most aggressive breast cancer subtypes and is characterized by abundant infiltrating immune cells within the microenvironment. As standard care, chemotherapy remains the fundamental neoadjuvant treatment in TNBC, and there is increasing evidence that supplementation with immune checkpoint inhibitors may potentiate the therapeutic efficiency of neoadjuvant chemotherapy (NAC). However, 20-60% of TNBC patients still have residual tumor burden after NAC and require additional chemotherapy; therefore, it is critical to understand the dynamic change in the tumor microenvironment (TME) during treatment to help improve the rate of complete pathological response and long-term prognosis. Traditional methods, including immunohistochemistry, bulk tumor sequencing, and flow cytometry, have been applied to elucidate the TME of breast cancer, but the low resolution and throughput may overlook key information. With the development of diverse high-throughput technologies, recent reports have provided new insights into TME alterations during NAC in four fields, including tissue imaging, cytometry, next-generation sequencing, and spatial omics. In this review, we discuss the traditional methods and the latest advances in high-throughput techniques to decipher the TME of TNBC and the prospect of translating these techniques to clinical practice.

Immune Checkpoint Inhibitors Combined with Targeted Therapy: The Recent Advances and Future Potentials

Immune checkpoint inhibitors (ICIs) have revolutionized the therapeutic landscape of cancer and have been widely approved for use in the treatment of diverse solid tumors. Targeted therapy has been an essential part of cancer treatment for decades, and in most cases, a special drug target is required. Numerous studies have confirmed the synergistic effect of combining ICIs with targeted therapy. For example, triple therapy of PD-L1 inhibitor atezolizumab plus BRAF inhibitor vemurafenib and MEK inhibitor cobimetinib has been approved as the first-line treatment in advanced melanoma patients with BRAF^V600 mutations. However, not all combinations of ICIs and targeted therapy work. Combining ICIs with EGFR inhibitors in non-small-cell lung cancer (NSCLC) with EGFR mutations only triggered toxicities and did not improve efficacy. Therefore, the efficacies of combinations of ICIs and different targeted agents are distinct. This review firstly and comprehensively covered the current status of studies on the combination of ICIs mainly referring to PD-1 and PD-L1 inhibitors and targeted drugs, including angiogenesis inhibitors, EGFR/HER2 inhibitors, PARP inhibitors and MAPK/ERK signaling pathway inhibitors, in the treatment of solid tumors. We discussed the underlying mechanisms, clinical efficacies, side effects, and potential predictive biomarkers to give an integrated view of the combination strategy and provide perspectives for future directions in solid tumors.

PD-L1 blockade in combination with carboplatin as immune induction in metastatic lobular breast cancer: the GELATO trial

Invasive lobular breast cancer (ILC) is the second most common histological breast cancer subtype, but ILC-specific trials are lacking. Translational research revealed an immune-related ILC subset, and in mouse ILC models, synergy between immune checkpoint blockade and platinum was observed. In the phase II GELATO trial ( NCT03147040 ), patients with metastatic ILC were treated with weekly carboplatin (area under the curve 1.5 mg ml-1 min-1) as immune induction for 12 weeks and atezolizumab (PD-L1 blockade; triweekly) from the third week until progression. Four of 23 evaluable patients had a partial response (17%), and 2 had stable disease, resulting in a clinical benefit rate of 26%. From these six patients, four had triple-negative ILC (TN-ILC). We observed higher CD8+ T cell infiltration, immune checkpoint expression and exhausted T cells after treatment. With this GELATO trial, we show that ILC-specific clinical trials are feasible and demonstrate promising antitumor activity of atezolizumab with carboplatin, particularly for TN-ILC, and provide insights for the design of highly needed ILC-specific trials.

A phase I/II study of preoperative letrozole, everolimus, and carotuximab in stage 2 and 3 hormone receptor-positive and Her2-negative breast cancer

PURPOSE

In nonmetastatic hormone receptor-positive and Her2-negative breast cancer, preoperative endocrine therapies can yield outcomes similar with chemotherapy. We evaluated the tolerability and preliminary antitumor activity of preoperative letrozole, everolimus, and carotuximab, a monoclonal antibody targeting endoglin, in nonmetastatic breast cancer.

METHODS

Eligible patients had newly diagnosed, stage 2 or 3, hormone receptor-positive and Her2/neu-negative breast cancer. Patients received escalating doses of everolimus; the dose of letrozole and carotuximab were fixed at 2.5 mg PO daily and 15 mg/kg intravenously every 2 weeks, respectively. The primary objective was to determine the safety and tolerability of the combination. Secondary objectives included pharmacokinetic and pharmacodynamic studies and assessments of antitumor activity.

RESULTS

Fifteen patients enrolled. The recommended phase 2 dose of everolimus in combination with letrozole and carotuximab was 10 mg PO daily. The most frequent adverse events were headache (67%), fatigue (47%), facial flushing and swelling (47%), gingival hemorrhage (40%), epistaxis (33%), nausea and vomiting (27%). Headache constituted a dose-limiting toxicity. At least two signs of mucocutaneous telangiectasia developed in 92% of patients. Carotuximab accumulated in the extravascular space and accelerated the biodistribution and clearance of everolimus. All patients had residual disease. Gene expression analyses were consistent with downregulation of genes involved in proliferation and DNA repair. Among 6 patients with luminal B breast cancer, 5 converted to luminal A after one cycle of therapy.

CONCLUSION

Letrozole, everolimus, and carotuximab were tolerated in combination at their single-agent doses. Pharmacokinetic studies revealed an interaction between everolimus and carotuximab.

TRIAL REGISTRATION

This trial is registered with ClinicalTrials.gov (Identifier: NCT02520063), first posted on August 11, 2015, and is active, not recruiting.

Leveraging transcriptomics for precision diagnosis: Lessons learned from cancer and sepsis

Diagnostics require precision and predictive ability to be clinically useful. Integration of multi-omic with clinical data is crucial to our understanding of disease pathogenesis and diagnosis. However, interpretation of overwhelming amounts of information at the individual level requires sophisticated computational tools for extraction of clinically meaningful outputs. Moreover, evolution of technical and analytical methods often outpaces standardisation strategies. RNA is the most dynamic component of all -omics technologies carrying an abundance of regulatory information that is least harnessed for use in clinical diagnostics. Gene expression-based tests capture genetic and non-genetic heterogeneity and have been implemented in certain diseases. For example patients with early breast cancer are spared toxic unnecessary treatments with scores based on the expression of a set of genes (e.g., Oncotype DX). The ability of transcriptomics to portray the transcriptional status at a moment in time has also been used in diagnosis of dynamic diseases such as sepsis. Gene expression profiles identify endotypes in sepsis patients with prognostic value and a potential to discriminate between viral and bacterial infection. The application of transcriptomics for patient stratification in clinical environments and clinical trials thus holds promise. In this review, we discuss the current clinical application in the fields of cancer and infection. We use these paradigms to highlight the impediments in identifying useful diagnostic and prognostic biomarkers and propose approaches to overcome them and aid efforts towards clinical implementation.

Immune and pathologic responses in patients with localized prostate cancer who received daratumumab (anti-CD38) or edicotinib (CSF-1R inhibitor)

BACKGROUND

The prostate tumor microenvironment (TME) is immunosuppressive, with few effector T cells and enrichment of inhibitory immune populations, leading to limited responses to treatments such as immune checkpoint therapies (ICTs). The immune composition of the prostate TME differs across soft tissue and bone, the most common site of treatment-refractory metastasis. Understanding immunosuppressive mechanisms specific to prostate TMEs will enable rational immunotherapy strategies to generate effective antitumor immune responses. Daratumumab (anti-CD38 antibody) and edicotinib (colony-stimulating factor-1 receptor (CSF-1R) inhibitor) may alter the balance within the prostate TME to promote antitumor immune responses.

HYPOTHESIS

Daratumumab or edicotinib will be safe and will alter the immune TME, leading to antitumor responses in localized prostate cancer.

PATIENTS AND METHODS

In this presurgical study, patients with localized prostate cancer received 4 weekly doses of daratumumab or 4 weeks of daily edicotinib prior to radical prostatectomy (RP). Treated and untreated control (Gleason score ≥8 in prostate biopsy) prostatectomy specimens and patient-matched pre- and post-treatment peripheral blood mononuclear cells (PBMCs) and bone marrow samples were evaluated. The primary endpoint was incidence of adverse events (AEs). The secondary endpoint was pathologic complete remission (pCR) rate.

RESULTS

Twenty-five patients were treated (daratumumab, n=15; edicotinib, n=10). All patients underwent RP without delays. Grade 3 treatment-related AEs with daratumumab occurred in 3 patients (12%), and no ≥grade 3 treatment-related AEs occurred with edicotinib. No changes in serum prostate-specific antigen (PSA) levels or pCRs were observed. Daratumumab led to a decreased frequency of CD38+ T cells, natural killer cells, and myeloid cells in prostate tumors, bone marrow, and PBMCs. There were no consistent changes in CSF-1R+ immune cells in prostate, bone marrow, or PBMCs with edicotinib. Neither treatment induced T cell infiltration into the prostate TME.

CONCLUSIONS

Daratumumab and edicotinib treatment was safe and well-tolerated in patients with localized prostate cancer but did not induce pCRs. Decreases in CD38+ immune cells were observed in prostate tumors, bone marrow, and PBMCs with daratumumab, but changes in CSF-1R+ immune cells were not consistently observed with edicotinib. Neither myeloid-targeted agent alone was sufficient to generate antitumor responses in prostate cancer; thus, combinations with agents to induce T cell infiltration (eg, ICTs) will be needed to overcome the immunosuppressive prostate TME.

Tumor immune microenvironment components and the other markers can predict the efficacy of neoadjuvant chemotherapy for breast cancer

Breast cancer is an epithelial malignant tumor that occurs in the terminal ducts of the breast. Neoadjuvant chemotherapy (NACT) is an important part of breast cancer treatment. Its purpose is to use systemic treatment for some locally advanced breast cancer patients, to decrease the tumor size and clinical stage so that non-operable breast cancer patients can have a chance to access surgical treatment, or patients who are not suitable for breast-conserving surgery can get the opportunity of breast-conserving. However, some patients who do not respond to NACT will lead deterioration in their condition. Therefore, prediction of NACT efficacy in breast cancer is vital for precision therapy. The tumor microenvironment (TME) has a crucial role in the carcinogenesis and therapeutic response of breast cancer. In this review, we summarized the immune cells, immune checkpoints, and other biomarkers in the TME that can evaluate the efficacy of NACT in treating breast cancer. We believe that the detection and evaluation of the TME components in breast cancer are helpful to predict the efficacy of NACT, and the prediction methods are in the prospect. In addition, we also summarized other predictive factors of NACT, such as imaging examination, biochemical markers, and multigene/multiprotein profiling.

Modification of Breast Cancer Milieu with Chemotherapy plus Dendritic Cell Vaccine: An Approach to Select Best Therapeutic Strategies

BACKGROUND

The addition of dendritic cell vaccines (DCV) to NAC could induce immune responses in those patients with residual disease (RD) by transforming the tumor microenvironment.

METHODS

Core diagnostic biopsies and surgical specimens from 80 patients (38 in the vaccinated group plus NAC (VG) and 42 in the control group (CG, treated only with NAC) were selected. We quantify TILs (CD8, CD4 and CD45RO) using immunohistochemistry and the automated cellular imaging system (ACIS III) in paired samples.

RESULTS

A CD8 rise in TNBC samples was observed after NAC plus DCV, changing from 4.48% in the biopsy to 6.70% in the surgical specimen, not reaching statistically significant differences (p = 0.11). This enrichment was seen in up to 67% of TNBC patients in the experimental arm as compared with the CG (20%). An association between CD8 TILs before NAC (4% cut-off point) and pathological complete response in the VG was found in the univariate and multivariate analysis (OR = 1.41, IC95% 1.05-1.90; p = 0.02, and OR = 2.0, IC95% 1.05-3.9; p = 0.03, respectively).

CONCLUSION

Our findings suggest that patients with TNBC could benefit from the stimulation of the antitumor immune system by using DCV together with NAC.

Clinical implications of the intrinsic molecular subtypes in hormone receptor-positive and HER2-negative metastatic breast cancer

Traditionally, the classification of breast cancer relies on the expression of immunohistochemical (IHC) biomarkers readily available in clinical practice. Using highly standardized and reproducible assays across patient cohorts, intrinsic molecular subtypes of breast cancer - also called "intrinsic subtypes" (IS) - have been identified based on the expression of 50 genes. Although IHC-based subgroups and IS moderately correlate to each other, they are not superimposable. In fact, non-luminal biology has been detected in a substantial proportion (5-20%) of hormone receptor-positive (HoR+) tumors, has prognostic value, and identifies reduced and increased sensitivity to endocrine therapy and chemotherapy, respectively. During tumor progression, a shift toward a non-luminal estrogen-independent and more aggressive phenotype has been demonstrated. Intrinsic genomic instability and cell plasticity, alone or combined with external constraints deriving from treatment selective pressure or interplay with the tumor microenvironment, may represent the determinants of such biological diversity between primary and metastatic disease, and during metastatic tumor evolution. In this review, we describe the distribution and the clinical behavior of IS as the disease progresses, focusing on HoR+/HER2-negative advanced breast cancer. In addition, we provide an overview of the ongoing clinical trials aiming to validate the predictive and prognostic value of IS towards their incorporation into routine care.

Association between Intratumoral CD8+ T Cells with FoxP3+ and CD163+ Cells: A Potential Immune Intrinsic Negative Feedback Mechanism for Acquired Immune Resistance

Acquired immune resistance (AIR) describes a situation in which cancer patients who initially responded clinically to immunotherapies, after a certain period of time, progress with their disease. Considering that AIR represents a feedback response of the tumor against the immune attack generated during the course of immunotherapies, it is conceivable that AIR may also occur before treatment initiation as a mechanism to escape endogenous adaptive antitumor immunity (EAAI). In the present study, we assessed the EAAI in paraffin-embedded breast primary tumor tissue samples and drew correlations with the clinical outcomes. In particular, we analyzed densities of CD8+ cells as elements mediating antitumor cytotoxicity, and of CD163+ and FoxP3+ cells as suppressor elements. We found a direct correlation between the densities of CD8+ cells and of CD163+ and/or FoxP3+ cells in the vast majority of patients' tumors. Importantly, the vast majority of patients whose tumors were overpopulated by CD8+ cells developed AIR, which was characterized by high intratumoral CD163+ and/or FoxP3+ cell densities and reduced overall survival (OS). We also showed that AIR depends on the levels of CD8+ cell-ratios in the tumor center to the invasive margin. Our data suggest that tumors develop AIR only when under a robust endogenous immune pressure.

Association of body mass index and inflammatory dietary pattern with breast cancer pathologic and genomic immunophenotype in the nurses' health study

BACKGROUND

Breast tumor immune infiltration is clearly associated with improved treatment response and outcomes in breast cancer. However, modifiable patient factors associated with breast cancer immune infiltrates are poorly understood. The Nurses' Health Study (NHS) offers a unique cohort to study immune gene expression in tumor and adjacent normal breast tissue, immune cell-specific immunohistochemistry (IHC), and patient exposures. We evaluated the association of body mass index (BMI) change since age 18, physical activity, and the empirical dietary inflammatory pattern (EDIP) score, all implicated in systemic inflammation, with immune cell-specific expression scores.

METHODS

This population-based, prospective observational study evaluated 882 NHS and NHSII participants diagnosed with invasive breast cancer with detailed exposure and gene expression data. Of these, 262 women (training cohort) had breast tumor IHC for four classic immune cell markers (CD8, CD4, CD20, and CD163). Four immune cell-specific scores were derived via lasso regression using 105 published immune expression signatures' association with IHC. In the remaining 620 patient evaluation cohort, we evaluated association of each immune cell-specific score as outcomes, with BMI change since age 18, physical activity, and EDIP score as predictors, using multivariable-adjusted linear regression.

RESULTS

Among women with paired expression/IHC data from breast tumor tissue, we identified robust correlation between novel immune cell-specific expression scores and IHC. BMI change since age 18 was positively associated with CD4+ (β = 0.16; p = 0.009), and CD163 novel immune scores (β = 0.14; p = 0.04) in multivariable analyses. In other words, for each 10 unit (kg/m2) increase in BMI, the percentage of cells positive for CD4 and CD163 increased 1.6% and 1.4%, respectively. Neither physical activity nor EDIP was significantly associated with any immune cell-specific expression score in multivariable analyses.

CONCLUSIONS

BMI change since age 18 was positively associated with novel CD4+ and CD163+ cell scores in breast cancer, supporting further study of the effect of modifiable factors like weight gain on the immune microenvironment.

Leveraging the Dynamic Immune Environment Triad in Patients with Breast Cancer: Tumour, Lymph Node, and Peripheral Blood

During the anti-tumour response to breast cancer, the primary tumour, the peripheral blood, and the lymph nodes each play unique roles. Immunological features at each site reveal evidence of continuous immune cross-talk between them before, during and after treatment. As such, immune responses to breast cancer are found to be highly dynamic and truly systemic, integrating three distinct immune sites, complex cell-migration highways, as well as the temporal dimension of disease progression and treatment. In this review, we provide a connective summary of the dynamic immune environment triad of breast cancer. It is critical that future studies seek to establish dynamic immune profiles, constituting multiple sites, that capture the systemic immune response to breast cancer and define patient-selection parameters resulting in more significant overall responses and survival rates for breast cancer patients.

The effect of neoadjuvant chemotherapy on tumor-infiltrating lymphocytes in patients with breast cancer

Aim: This study investigated the effect of neoadjuvant chemotherapy (NAC) on stromal tumor-infiltrating lymphocytes (sTILs) and their treatment response. Materials & methods: One hundred fifteen patients with pre-NAC core biopsies and post-NAC surgical resection specimens were reviewed. Results: There was no significant change between pre- and post-treatment sTILs. Both pre- and post-NAC sTILs were significantly lower in patients with luminal A subtype. An increase in sTILs was observed in 21 (25.9%) patients after NAC, a decrease in 29 (35.8%) and no change in 31 (38.3%; p = 0.07). Pretreatment sTIL density was independent predictor of pathological complete response in multivariate analyses (odds ratio: 1.025, 95% CI: 1.003-1.047; p = 0.023). Conclusion: High sTIL density in core biopsies was independently related to pathological complete response. In addition, ER appears to be the most crucial factor determining the rate of sTIL.

Immune Checkpoint Blockade in Hormone Receptor-Positive Breast Cancer: Resistance Mechanisms and Future Perspectives

Anti-programmed cell death protein 1 immunotherapy has been incorporated in the treatment algorithm of triple-negative breast cancer (TNBC). However, clinical trial results for patients with hormone receptor (HR)-positive disease appear less compelling. HR-positive tumors exhibit lower levels of programmed death-ligand 1 expression in comparison with their triple-negative counterparts. Moreover, signaling through estrogen receptor alters the immune microenvironment, rendering such tumors immunologically "cold." To explain differential responses to immune checkpoint blockade, this review interrogates differences between HR-positive and TNBC. Starting from distinct genomic features, we further present disparities concerning the tumor microenvironment and finally, we summarize early-phase clinical trial results on promising novel immunotherapy combinations.

CLEC1B is a Promising Prognostic Biomarker and Correlated with Immune Infiltration in Hepatocellular Carcinoma

Purpose

C-type lectin domain family 1 member B (CLEC1B) is a protein-coding gene involved in various processes, such as platelet activation, tumor cell metastasis and separation of blood/lymphatic vessels. However, how CLEC1B plays its role in hepatocellular carcinoma (HCC) has not been well studied. The purpose of this study was to investigate the clinical significance and biological function of CLEC1B in HCC.

Patients and Methods

Based on (The Cancer Genome Atlas) TCGA database, CLEC1B expression matrix and corresponding clinical information were extracted. ROC curves and Kaplan–Meier method were generated to evaluate the value of CLEC1B as a diagnostic and prognostic biomarker. Moreover, single-gene difference analysis constructed by DESeq2 method and then the related genes were used to predict CLEC1B-related signaling pathways. The ssGSEA algorithm was conducted for studies related to immune infiltration. CLEC1B protein expression was evaluated and immunohistochemistry in HCC tissues through tissue microarray. Finally, the relationship between CLEC1B expression and T cell infiltration was assessed according to tissue microarray.

Results

The mRNA and protein levels of CLEC1B were significantly down-regulated in HCC compared to paired normal tissues, which were further verified in clinical tissue samples. ROC curves and Kaplan–Meier survival analysis suggested the significant diagnostic and clinical prognostic value of CLEC1B. Meanwhile, downregulation of CLEC1B was significantly associated with clinical parameters such as clinical tumor vascular invasion and distant metastasis. Moreover, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene set enrichment (GSEA) analysis indicated that CLEC1B has significant association with immune function. Finally, immune infiltration analysis indicated that CLEC1B was significantly associated with immune cell subsets and affected the efficacy of immunotherapy in cancer patient.

Conclusion

Collectively, our findings suggested that CLEC1B could be a promising prognostic biomarker in HCC and its expression was related to immune cell infiltration.

Tumor-Infiltrating Lymphocytes in Patients With Advanced Laryngeal Cancer Undergoing Bioselection

OBJECTIVE

Bioselection to assess tumor response after induction chemotherapy has been introduced as an alternative treatment strategy to total laryngectomy for patients with advanced larynx squamous cell carcinoma (LSCC). Tumor-infiltrating lymphocytes (TILs) have proven to serve as prognostic biomarkers in head and neck cancer but have not been evaluated as a way to select patients for treatment paradigms. The aim of this study is to evaluate the role of pretreatment TILs in patients with advanced LSCC undergoing the bioselection paradigm.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary care hospital.

METHODS

Patients with advanced LSCC treated with bioselection and available tissue were included (N = 76). Patients were stratified into CD8-low and CD8-high cohorts by using the median TIL count. Kaplan-Meier survival analysis and multivariate cox regression were performed with SPSS version 26 (IBM).

RESULTS

After controlling for tobacco use, tumor site, and stage, a high CD8 TIL count was an independent predictor of improved 5-year disease-specific survival (hazard ratio, 0.17 [95% CI, 0.03-0.84]; P = .03). CD8 TIL counts did not predict response to induction chemotherapy; however, subgroup analysis of patients treated with chemoradiation therapy revealed that CD8 TIL count was significantly associated with degree of response (P = .012).

CONCLUSION

These findings support prior data published by our group showing that TILs are predictive of disease-specific survival in patients with head and neck cancer. CD8 TIL counts were significantly associated with degree of clinical response after induction chemotherapy. These results suggest that pretreatment assessment of tumor-infiltrating CD8 cells could be useful in selecting patients.

PD-L1 expression in breast invasive ductal carcinoma with incomplete pathological response to neoadjuvant chemotherapy

Objectives:

To investigate the expression of programmed death-ligand 1 (PD-L1) in breast cancer in association with incomplete pathological response (PR) to neoadjuvant chemotherapy (NAC).

Methods

PD-L1 expression was evaluated using immunohistochemistry in post-operative, post-NAC samples of 60 patients (n = 60) diagnosed with breast invasive ductal carcinoma with incomplete PR to NAC, including 31 matched pre-NAC and post-NAC samples (n = 31). PD-L1 protein expression was assessed using three scoring approaches, including the tumor proportion score (TPS), the immune cell score (ICS), and the combined tumor and immune cell score (combined positive score, CPS) with a 1% cut-off.

Results

In the post-operative, post-NAC samples (n = 60), positive expression rate of PD-L1 was observed in 18.3% (11/60) of cases by TPS, 31.7% (19/60) by ICS, and 25% (15/60) by CPS. In matched samples, positive expression rate of PD-L1 was observed in 19.3% (6/31) of patients by TPS, 51.6% (16/31) by ICS, and 19.3% (6/31) by CPS in pre-NAC specimens, while it was observed in 22.6% (7/31) of matched post-NAC samples by TPS, 22.6% (7/31) by ICS, and 19.3% (6/31) by CPS. In the matched samples, there was a significant decrease in PD-L1 immunoexpression using ICS in post-NAC specimens (McNemar’s, p = 0.020), while no significant differences were found using TPS and CPS between pre- and post-NAC samples (p = 1.000, p = 0.617; respectively). PD-L1 immunoexpression determined by TPS or CPS was only significantly associated with ER status (p = 0.022, p = 0.021; respectively), but not with other clinicopathological variables. We could not establish a correlation between PD-L1 expression and the overall survival rate (p > 0.05). There were no significant differences in the tumor infiltrating lymphocytes count between the paired pre- and post-NAC samples (t = 0.581, p = 0.563 or Wilcoxon’s Signed Rank test; z = -0.625, p = 0.529).

Conclusion

Our findings indicate that PD-L1 protein expression in infiltrating immune cells was significantly reduced in breast tumors that developed incomplete PR following the exposure to NAC.

Spatial and Temporal Heterogeneity of Tumor-Infiltrating Lymphocytes in Advanced Urothelial Cancer

Checkpoint inhibitors targeting PD-(L)1 induce objective responses in 20% of patients with metastatic urothelial cancer (UC). CD8+ T cell infiltration has been proposed as a putative biomarker for response to checkpoint inhibitors. Nevertheless, data on spatial and temporal heterogeneity of tumor-infiltrating lymphocytes in advanced UC are lacking. The major aims of this study were to explore spatial heterogeneity for lymphocyte infiltration and to investigate how the immune landscape changes during the disease course. We performed multiplex immunohistochemistry to assess the density of intratumoral and stromal CD3+, CD8+, FoxP3+ and CD20+ immune cells in longitudinally collected samples of 49 UC patients. Within these samples, spatial heterogeneity for lymphocyte infiltration was observed. Regions the size of a 0.6 tissue microarray core (0.28 mm2) provided a representative sample in 60.6 to 71.6% of cases, depending on the cell type of interest. Regions of 3.30 mm2, the median tumor surface area in our biopsies, were representative in 58.8 to 73.8% of cases. Immune cell densities did not significantly differ between untreated primary tumors and metachronous distant metastases. Interestingly, CD3+, CD8+ and FoxP3+ T cell densities decreased during chemotherapy in two small cohorts of patients treated with neoadjuvant or palliative platinum-based chemotherapy. In conclusion, spatial heterogeneity in advanced UC challenges the use of immune cell infiltration in biopsies as biomarker for response prediction. Our data also suggests a decrease in tumor-infiltrating T cells during platinum-based chemotherapy.

Understanding resistance to immune checkpoint inhibitors in advanced breast cancer

INTRODUCTION

The addition of immune checkpoint inhibitors (ICIs) to frontline chemotherapy has improved survival for patients with advanced triple-negative breast cancer (TNBC) expressing programmed death-ligand 1 (PD-L1). Nonetheless, most patients develop resistance, with outcomes remaining poor for this population. Moreover, unsatisfactory activity has been observed with ICIs in PD-L1-negative TNBC and in other breast cancer (BC) subtypes, warranting a deeper understanding of resistance to ICIs in BC.

AREAS COVERED

We discuss the immune landscape of distinct BC subtypes, review the clinical activity of immunotherapy in BC, and highlight strategies under development to overcome resistance to ICIs.

EXPERT OPINION

Activity and resistance to ICIs in BC are strongly related to the intrinsic immunophenotype of the tumor tissue. Several promising biomarkers reflecting the immunological state of BC are emerging, with only PD-L1 expression currently adopted into clinical practice. However, limitations make of PD-L1 a sub-optimal biomarker for patient selection, which require efforts to integrate this marker with other immunological features. Concomitantly, a wide variety of drug combinations designed to overcome immune-resistance are being evaluated, with some encouraging signals observed in early-phase trials. Combination strategies tailored to patient and tumor immunophenotype may allow to overcome resistance and fully exploit the potential of ICIs.

Development and Clinical Validation of Novel 8-Gene Prognostic Signature Associated With the Proportion of Regulatory T Cells by Weighted Gene Co-Expression Network Analysis in Uterine Corpus Endometrial Carcinoma

Background

Uterine corpus endometrial carcinoma (UCEC) is a gynecological malignant tumor with low survival rate and poor prognosis. The traditional clinicopathological staging is insufficient to estimate the prognosis of UCEC. It is necessary to select a more effective prognostic signature of UCEC to predict the prognosis and immunotherapy effect of UCEC.

Methods

CIBERSORT and weighted correlation network analysis (WGCNA) algorithms were combined to screen modules related to regulatory T (Treg) cells. Subsequently, univariate, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression analyses were used to identify the genes in key modules. The difference in overall survival (OS) between high- and low-risk patients was analyzed by Kaplan-Meier analysis. The Tregs-related risk signature (TRRS) was screened by uni- and multivariate Cox analyses. Afterward, we analyzed the expression difference of TRRS and verified its ability to predict the prognosis of UCEC and the effect of immunotherapy.

Results

Red module has the highest correlation with Tregs among all clustered modules. Pathways enrichment indicated that the related processes of UCEC were primarily associated to the immune system. Eight genes (ZSWIM1, NPRL3, GOLGA7, ST6GALNAC4, CDC16, ITPK1, PCSK4, and CORO1B) were selected to construct TRRS. We found that this TRRS is a significantly independent prognostic factor of UCEC. Low-risk patients have higher overall survival than high-risk patients. The immune status of different groups was different, and tumor-related pathways were enriched in patients with higher risk score. Low-risk patients are more likely take higher tumor mutation burden (TMB). Meanwhile, they are more sensitive to chemotherapy than patients with high-risk score, which indicated a superior prognosis. Immune checkpoints such as PD-1, CTLA4, PD-L1, and PD-L2 all had a higher expression level in low-risk group. TRRS expression really has a relevance with the sensitivity of UCEC patients to chemotherapeutic drugs.

Conclusion

We developed and validated a TRRS to estimate the prognosis and reflect the immune status of UCEC, which could accurately assess the prognosis of patients with UCEC and supply personalized treatments for them.

Neoadjuvant eribulin in HER2-negative early-stage breast cancer (SOLTI-1007-NeoEribulin): a multicenter, two-cohort, non-randomized phase II trial

Eribulin prolongs overall survival in patients with pre-treated advanced breast cancer. However, no biomarker exists to prospectively select patients who will benefit the most from this drug. SOLTI-1007-NeoEribulin is a phase II, open-label, two-cohort, exploratory pharmacogenomic study in patients with clinical stage I–II HER2-negative breast cancer receiving neoadjuvant eribulin monotherapy treatment. Primary objective was to explore the association of baseline tumor gene expression with pathological complete response in the breast (pCR_B) at surgery. Key secondary objectives were pCR_B rates in all patients and according to HR status, gene expression changes during treatment and safety. One-hundred one hormonal receptor-positive (HR + ) and seventy-three triple-negative breast cancer (TNBC) patients were recruited. The pCR_B rates were 6.4% in all patients, 4.9% in HR + disease and 8.2% in TNBC. The TNBC cohort was interrupted due to a progression disease rate of 30.1%. The pCR_B rates differed according to intrinsic subtypes: 28.6% in HER2-enriched, 11.1% in Normal-like, 7.9% in Luminal B, 5.9% in Basal-like and 0% in Luminal A (HER2-enriched vs. others odds ratio = 7.05, 95% CI 1.80–42.14; p-value = 0.032). Intrinsic subtype changes at surgery occurred in 33.3% of cases, mostly (49.0%) Luminal B converting to Luminal A or Basal-like converting to Normal-like. Baseline tumor-infiltrating lymphocytes (TILs) were significantly associated with pCR. Eribulin showed a good safety profile with a low response and pCR_B rates. Patients with HER2-negative disease with a HER2-enriched profile may benefit the most from eribulin. In addition, significant biological activity of eribulin is observed in Luminal B and Basal-like subtypes.

Prognostic significance of tumor-infiltrating lymphocytes in premenopausal, luminal breast cancer treated with adjuvant endocrine therapy

PURPOSE

Tumor-infiltrating lymphocytes (TILs) have strong prognostic value in triple-negative and HER2-enriched breast cancer, but their prognostic role in luminal breast cancer (LBC) is less clear. Here, we assessed the overall TIL levels and CD8+ T-cells in relation to the prognosis of LBC patients from China.

METHODS AND RESULTS

A total of 596 patients with LBC who were premenopausal and treated with adjuvant endocrine therapy were included. Among them, 160 cases were evaluated for CD8 by immunohistochemical (IHC) staining. Whole-section hematoxylin and eosin and IHC staining were visually assessed for stromal TILs (sTILs), stromal CD8+ T-cells (sCD8), and intratumoral CD8+ T-cells (iCD8). Multivariable analyses were used to test the associations between TILs and disease-free survival (DFS) and overall survival (OS) with the adjustment for clinicopathologic characteristics and treatment. High sTILs (≥10%) were associated with high histologic grade (P<0.001), luminal B/HER2- (P<0.001), luminal B/HER2+ subtype (P=0.002), and high Ki67 expression (≥25%; P=0.014). Similar associations were observed for sCD8 but not for iCD8. While sTILs and sCD8 were not associated with either DFS or OS, the presence of iCD8 (≥1%) was associated with better DFS in both univariate (HR=0.51, 95% CI 0.26-0.96, P=0.042) and multivariate (HR=0.48, 95% CI 0.25-0.92, P=0.027) analyses. Similar but less significant associations were found for iCD8 and OS (adjusted HR=0.35, 95% CI 0.11-1.10, P=0.073).

CONCLUSIONS

Among Chinese premenopausal patients with LBC, iCD8 demonstrated suggestive associations with favorable outcome. In contrast, although sTILs and sCD8 were associated with more aggressive tumor features, they did not appear to be associated with clinical outcome.

Immune-Related Genes to Construct a Novel Prognostic Model of Breast Cancer: A Chemosensitivity-Based Study

Chemotherapy combined with surgery is effective for patients with breast cancer (BC). However, chemoresistance restricts the effectiveness of BC treatment. Immune microenvironmental changes are of pivotal importance for chemotherapy responses. Thus, we sought to construct and validate an immune prognostic model based on chemosensitivity status in BC. Here, immune-related and chemosensitivity-related genes were obtained from GSE25055. Then, univariate analysis was employed to identify prognostic-related gene pairs from the intersection of the two parts of the genes, and modified least absolute shrinkage and selection operator (LASSO) analysis was performed to build a prognostic model. Furthermore, we investigated the efficiency of this model from various perspectives, and further validation was performed using the Cancer Genome Atlas (TCGA) cohorts. We identified seven immune and chemosensitivity-related gene pairs and incorporated them into the Cox regression model. After multilevel validation, the risk model was found to be closely related to the survival rate, various clinical characteristics, tumor mutation burden (TMB) score, immune checkpoints, and response to chemotherapeutic drugs. In addition, the model was verified to exhibit predictive capacity as an independent factor over other candidate clinical features. Notably, the constructed nomogram was more accurate than any single factor. Altogether, the risk score model and the nomogram have potential predictive value and may have important practical implications.

Breast cancer immune microenvironment: from pre-clinical models to clinical therapies

The breast cancer tumour microenvironment (BC-TME) is characterized by significant cellular and spatial heterogeneity that has important clinical implications and can affect response to therapy. There is a growing need to develop methods that reliably quantify and characterize the BC-TME and model its composition and functions in experimental systems, in the hope of developing new treatments for patients. In this review, we examine the role of immune-activating cells (including tumour-infiltrating lymphocytes and natural killer cells) and immune inhibitory cells (including T regulatory cells, tumour-associated macrophages and myeloid-derived suppressor cells) in the BC-TME. We summarize methods being used to characterize the microenvironment, with specific attention to pre-clinical models including co-cultures, organoids, and genetically modified and humanized mouse models. Finally, we explore the implications and applications of existing preclinical data for drug development and highlight several drugs designed to alter the BC-TME in order to improve treatment outcomes for patients.

P10s-PADRE vaccine combined with neoadjuvant chemotherapy in ER-positive breast cancer patients induces humoral and cellular immune responses

Breast cancer patients diagnosed with HR+/HER2– tumors face a persistent risk of distant recurrence long after completion of their treatment. Strategies to induce anti-tumor immune responses could complement standard-of-care therapies for these patients. The current study was performed to examine the feasibility, safety and immunogenicity of adding P10s-PADRE to standard-of-care chemotherapy in HR+/HER2− early-stage breast cancer patients. Twenty-five subjects were treated in a single-arm Phase Ib clinical trial. Five different immunization schedules were considered to evaluate the feasibility of eliciting an immune response. The primary immunogenicity endpoint was antibody titer. The expression of several activation markers on natural killer (NK) cells and serum concentrations of Th1/Th2 cytokines were also examined. The percentage of tumor-infiltrating lymphocytes (TILs) was determined. Antibody response was superior in schedule C where 3 weekly immunizations preceded the first dose of chemotherapy. A significant change in CD16, NKp46 and CD94 expression levels on NK cells and a rise in serum content of IFN-γ was observed after treatment. Schedule C showed an increase in TILs in residual lesions. The combination therapy is safe and immunogenic with treatment schedule C being immunologically promising. Randomized trials focused on long-term survival outcomes are needed to evaluate clinical benefits.

Prognostic significance of T-cell-inflamed gene expression profile and PD-L1 expression in patients with esophageal cancer

Purpose

The ability of the T‐cell–inflamed gene expression profile (GEP) to predict clinical outcome in esophageal cancer (EC) is unknown. This retrospective observational study assessed the prognostic value of GEP and programmed death ligand 1 (PD‐L1) expression in patients with EC treated in routine clinical practice.

Methods

Tumor samples of 294 patients from three centers in Denmark, South Korea, and the United States, collected between 2005 and 2017, were included. T‐cell–inflamed GEP score was defined as non‐low or low using a cutoff of −1.54. A combined positive score (CPS) ≥10 was defined as PD‐L1 expression positivity. Associations between overall survival (OS) and GEP status and PD‐L1 expression were explored by Cox proportional hazards models adjusting for age, sex, histology, stage, and performance status.

Results

Median age was 65 years; 63% of patients had adenocarcinoma (AC) and 37% had squamous cell carcinoma (SCC). Thirty‐six percent of tumors were GEP non‐low, with higher prevalence in AC (46%) than SCC (18%). Twenty‐one percent were PD‐L1–positive: 32% in South Korean samples versus 16% in non‐Asian samples and 26% in SCC versus 18% in AC. GEP scores and PD‐L1 CPS were weakly correlated (Spearman’s R = 0.363). OS was not significantly associated with GEP status (non‐low vs low; adjusted hazard ratio, 0.91 [95% CI, 0.69–1.19]) or PD‐L1 expression status.

Conclusion

Neither GEP nor PD‐L1 expression was a prognostic marker in Asian and non‐Asian patients with EC.

Combined CTLA-4 and PD-L1 blockade in patients with chemotherapy-naïve metastatic castration-resistant prostate cancer is associated with increased myeloid and neutrophil immune subsets in the bone microenvironment

BACKGROUND

Immune checkpoint therapy (ICT) has low response rates in patients with metastatic castration-resistant prostate cancer (mCRPC), in part due to few T cells in the tumor microenvironment (TME). Anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) promotes intratumoral T cell infiltration but induces upregulation of PD-1 and programmed death ligand-1 (PD-L1) within the prostate TME. Combined anti-CTLA-4 plus anti-PD-1 can partly overcome this adaptive resistance and was recently shown to augment responses in patients with mCRPC with measurable disease. Although bone is the most common site of metastasis in prostate cancer, patients with bone-predominant disease are frequently excluded from trials because they lack measurable disease, which limits assessment of disease progression and tissue sampling. We therefore designed this study to investigate combined ICT in mCRPC to bone.

HYPOTHESIS

Combined anti-CTLA-4 (tremelimumab) plus anti-PD-L1 (durvalumab) is safe and well tolerated in patients with chemotherapy-naïve mCRPC to bone.

PATIENTS AND METHODS

In this single-arm pilot study, men with chemotherapy-naïve mCRPC to bone received tremelimumab (75 mg intravenous) plus durvalumab (1500 mg intravenous) every 4 weeks (up to four doses), followed by durvalumab (1500 mg intravenous) maintenance every 4 weeks (up to nine doses). The primary endpoint was incidence of adverse events. Secondary endpoints included serum prostate-specific antigen (PSA), progression-free survival (PFS), radiographic PFS (rPFS), and maximal PSA decline.

RESULTS

Twenty-six patients were treated between August 8, 2017 and March 28, 2019. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 11 patients (42%), with no grade 4 or 5 events. TRAEs leading to discontinuation occurred in three patients (12%). PSA decline ≥50% occurred in three patients (12%). Six patients (24%) achieved stable disease for >6 months. At a median follow-up of 43.6 months, median rPFS was 3.7 months (95% CI: 1.9 to 5.7), and median overall survival was 28.1 months (95% CI: 14.5 to 37.3). Post-treatment evaluation of the bone microenvironment revealed transcriptional upregulation in myeloid and neutrophil immune subset signatures and increased expression of inhibitory immune checkpoints.

CONCLUSIONS

Tremelimumab plus durvalumab was safe and well tolerated in patients with chemotherapy-naïve mCRPC to bone, with potential activity in a small number of patients as measured by rPFS. Combination of CTLA-4 and PD-L1 blockade with therapies targeting the myeloid compartment or other inhibitory immune receptors may be necessary to overcome mechanisms of resistance within prostate bone microenvironment.

TRIAL REGISTRATION NUMBER

NCT03204812.

Characterization of inflammatory changes in the breast cancer associated adipose tissue and comparison to the unaffected contralateral breast

BACKGROUND

Adipose tissue has emerged as an important window into cancer pathophysiology, revealing potential targets for novel therapeutic interventions. The goal of this study was to compare the breast adipose tissue (BrAT) immune milieu surrounding breast carcinoma and contralateral unaffected breast tissue obtained from the same patient.

MATERIALS AND METHODS

Patients undergoing bilateral mastectomy for unilateral breast cancer were enrolled for bilateral BrAT collection at the time of operation. After BrAT was processed, adipocyte and stromal vascular fraction (SVF) gene expression was quantified by PCR. SVF cells were also processed for flow cytometric immune cell characterization.

RESULTS

Twelve patients underwent bilateral mastectomy for unilateral ductal carcinoma. BrAT adipocyte CXCL2 gene expression trended higher in the tumor-affected breast as compared to the unaffected breast. Macrophage MCP-1 and PPARγ gene expression also tended to be higher in the tumor-affected breasts. T cell gene expression of FOXP3 (p = 0.0370) were significantly greater in tumor-affected breasts than unaffected breasts. Affected BrAT contained higher numbers of Th2 CD4⁺ cells (p = 0.0165) and eosinophils (p = 0.0095) while trending towards increased macrophage and lower Th1 CD4⁺ cells infiltration than tumor-affected BrAT.

CONCLUSION

This preliminary study aimed to identify the immunologic environment present within BrAT and is the first to directly compare this in individual patients' tumor-associated and unaffected BrAT. These findings suggest that cancer-affected BrAT had increased levels of T cell specific FOXP3 and higher levels of anti-inflammatory/regulatory cells compared to the contralateral BrAT.

A review of the endocrine resistance in hormone-positive breast cancer

Hormone-positive breast cancer (BC) is a unique heterogeneous disease with a favorable prognosis compared to other types of breast cancer. As tumor biology influences the prognosis and clinical treatment, a deep understanding of how the molecular mechanisms regulate hormone sensitivity or resistance is critical in improving the efficacy and overcoming the endocrine resistance. This article comprehensively reviews the endocrine resistance in hormone-positive BC from a molecular and genetic perspective, encompassing the updated treatment and developing direction. This review includes the mechanisms of hormone resistance, which vary from epigenetic changes, crosstalk between signaling networks, cell cycle aberrance, and even change in the tumor microenvironment (TME) or stem cell. These mechanisms may contribute to treatment resistance. Current targeted therapy for hormone-resistant tumors includes PI3K/AKT/mTOR and cdk4/6 inhibitors. Several relevant pathways, biomarkers, and predictor genes have also been identified. Immunotherapy so far has a relatively less crucial role in hormone-positive than in triple-negative BC. Furthermore, the methodology to identify the PDL1 is not standardized. In a molecule and gene study, next-generation sequencing with circulating tumor DNA (ctDNA) has recently appeared as a sensitive and minimally invasive tool worth investigating.

Endogenous and Therapeutic Estrogens: Maestro Conductors of the Microenvironment of ER+ Breast Cancers

Estrogen receptor alpha (ERα) marks heterogeneous breast cancers which display a repertoire of somatic genomic mutations and an immune environment that differs from other breast cancer subtypes. These cancers also exhibit distinct biological behaviors; despite an overall better prognosis than HER2+ or triple negative breast cancers, disseminated dormant cells can lead to disease recurrence decades after the initial diagnosis and treatment. Estrogen is the best studied driver of these cancers, and antagonism or reduction of estrogen activity is the cornerstone of therapeutic approaches. In addition to reducing proliferation of ERα+ cancer cells, these treatments also alter signals to multiple other target cells in the environment, including immune cell subpopulations, cancer-associated fibroblasts, and endothelial cells via several distinct estrogen receptors. In this review, we update progress in our understanding of the stromal cells populating the microenvironments of primary and metastatic ER+ tumors, the effects of estrogen on tumor and stromal cells to modulate immune activity and the extracellular matrix, and net outcomes in experimental and clinical studies. We highlight new approaches that will illuminate the unique biology of these cancers, provide the foundation for developing new treatment and prevention strategies, and reduce mortality of this disease.

Proteomics of Primary Uveal Melanoma: Insights into Metastasis and Protein Biomarkers

Uveal melanoma metastases are lethal and remain incurable. A quantitative proteomic analysis of 53 metastasizing and 47 non-metastasizing primary uveal melanoma (pUM) was pursued for insights into UM metastasis and protein biomarkers. The metastatic status of the pUM specimens was defined based on clinical data, survival histories, prognostic analyses, and liver histopathology. LC MS/MS iTRAQ technology, the Mascot search engine, and the UniProt human database were used to identify and quantify pUM proteins relative to the normal choroid excised from UM donor eyes. The determined proteomes of all 100 tumors were very similar, encompassing a total of 3935 pUM proteins. Proteins differentially expressed (DE) between metastasizing and non-metastasizing pUM (n = 402) were employed in bioinformatic analyses that predicted significant differences in the immune system between metastasizing and non-metastasizing pUM. The immune proteins (n = 778) identified in this study support the immune-suppressive nature and low abundance of immune checkpoint regulators in pUM, and suggest CDH1, HLA-DPA1, and several DE immune kinases and phosphatases as possible candidates for immune therapy checkpoint blockade. Prediction modeling identified 32 proteins capable of predicting metastasizing versus non-metastasizing pUM with 93% discriminatory accuracy, supporting the potential for protein-based prognostic methods for detecting UM metastasis.

Luminal Breast Cancer: Risk of Recurrence and Tumor-Associated Immune Suppression

Hormone-receptor positive (HR+) breast cancer (BC) (including the luminal A and the luminal B subtypes) is the most common type of tumor in women diagnosed with early-stage BC (EBC). It represents a highly heterogeneous subgroup that is characterized by different risks of relapse. The aim of this review is to discuss the possible role played by the immune response in predicting this risk, along with the most common clinical and pathological factors and molecular tools that have been developed and are already in use. As opposed to what has previously been observed in the most aggressive human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancer (TNBC) subtypes, a high proportion of tumor-infiltrating lymphocytes (TILs)-reflecting a spontaneous and pre-existing immune response to the tumor-has been linked to a worse prognosis in HR+ EBC. This work provides some immune biological rationale explaining these findings and provides the basics to understand the principal clinical trials that are testing immunotherapy in HR+ (luminal) BC.