Low-risk triple-negative breast cancers: Clinico-pathological and molecular features

PU-H71 (NSC 750424): a molecular masterpiece that targets HSP90 in cancer and beyond

Heat shock protein 90 (HSP90) is a pivotal molecular chaperone with multifaceted roles in cellular health and disease. Herein, we explore how HSP90 orchestrates cellular stress responses, particularly through its partnership with heat shock factor 1 (HSF-1). PU-H71, a selective inhibitor of HSP90, demonstrates significant potential in cancer therapy by targeting a wide array of oncogenic pathways. By inducing the degradation of multiple client proteins, PU-H71 disrupts critical signaling pathways such as MAPK, PI3K/Akt, JAK/STAT, EGFR, and mTOR, which are essential for cancer cell survival, proliferation, and metastasis. We examined its impact on combating triple-negative breast cancer and enhancing the effectiveness of carbon-ion beam therapy, offering new avenues for cancer treatment. Furthermore, the dual inhibition of HSP90A and HSP90B1 by PU-H71 proves highly effective in the context of myeloma, providing fresh hope for patients with this challenging malignancy. We delve into its potential to induce apoptosis in B-cell lymphomas that rely on Bcl6 for survival, highlighting its relevance in the realm of hematologic cancers. Shifting our focus to hepatocellular carcinoma, we explore innovative approaches to chemotherapy. Moreover, the current review elucidates the potential capacity of PU-H71 to suppress glial cell activation paving the way for developing novel therapeutic strategies for neuroinflammatory disorders. Additionally, the present report also suggests the promising role of PU-H71 in JAK2-dependent myeloproliferative neoplasms. Eventually, our report sheds more light on the multiple functions of HSP90 protein as well as the potential therapeutic benefit of its selective inhibitor PU-H71 in the context of an array of diseases, laying the foundations for the development of novel therapeutic approaches that could achieve better treatment outcomes.

Quercetin inhibits the epithelial-mesenchymal transition and reverses CDK4/6 inhibitor resistance in breast cancer by regulating circHIAT1/miR-19a-3p/CADM2 axis

Breast cancer (BC) cells have a high risk of metastasis due to epithelial-mesenchymal transition (EMT). Palbociclib (CDK4/6 inhibitor) is an approved drug for BC treatment. However, the drug resistance and metastasis can impair the treatment outcome of Palbociclib. Understanding the mechanisms of EMT and Palbociclib drug resistance in BC is conducive to the formulation of novel therapeutic strategy. Here, we investigated the role of circHIAT1/miR-19a-3p/CADM2 axis in modulating EMT and Palbociclib resistance in BC. circHIAT1 and CADM2 were down-regulated in BC tissues and cell lines, and miR-19a-3p showed an up-regulation. circHIAT1 could interact with miR-19a-3p and suppress its activity, while miR-19a-3p functioned to negatively regulate CADM2. Forced over-expression of circHIAT1 could impaired the EMT status and migratory ability of BC cells, and this effect was inhibited by miR-19a-3p mimic. In addition, we also generated Palbociclib resistant BC cells, and showed that circHIAT1 and CADM2 were down-regulated in the resistant BC cells while miR-19a-3p showed an up-regulation. Forced circHIAT1 over-expression re-sensitized BC cells to Palbociclib treatment. Quercetin, a bioactive flavonoid, could suppressed the migration and invasion of BC cells, and re-sensitized BC cells to Palbociclib. The anti-cancer effect of quercetin could be attributed to its regulatory effect on circHIAT1/miR-19a-3p/CADM2 axis. In vivo tumorigenesis experiment further revealed that quercetin administration enhanced the anti-cancer effect of Palbociclib, an effect was dependent on the up-regulation of circHIAT1 by quercetin. In summary, this study identified quercetin as a potential anti-cancer compound to reverse Palbociclib resistance and impair EMT in BC cells by targeting circHIAT1/miR-19a-3p/CADM2 axis.

Should the Breast Cancer Staging System be Revised?

OBJECTIVE

The purpose of this study was to determine whether breast cancer patients at stage T2N0 with tumor size ≥4 cm and <4 cm.

METHOD

Patients with T2N0 stage breast cancer diagnosed between 2010 and 2019 were analyzed in 2 groups as <4 cm (T2a) and ≥4 cm (T2b) in the study using the SEER 17 Research Plus database. The patients' clinicopathological characteristics and oncological outcomes were included. Group comparisons of prognostic factors, overall survival (OS), and cancer-specific survival (CSS) were made.

RESULTS

In this study, which involved 70971 patients, the T2a group had higher 5-year OS rate (87.2 ± .2 vs 80.8 ± .5%) and 5-year CSS rate (93.7 ± .1% vs 89.4 ± .4%) than the T2b group (P < .001). Univariate analysis revealed that the overall risk of death was 1.5 times higher in T2b than T2a (HR: 1.533 [95% CI: 1.450-1.622], P < .001), whereas multivariate analysis demonstrated the risk was 1.4 times higher (HR: 1.384 [95% CI: 1.307-1.466], P < .001). The risk of cancer-specific death was 1.7 times higher in univariate analysis (HR: 1.691 [95% CI: 1.561-1.832], P < .001) and 1.4 times higher in multivariate analysis (HR: 1.420 [95% CI: 1.309-1.541], P < .001).

CONCLUSION

Overall survival and BCSS rates in stage T2b breast cancer patients are significantly lower than in T2a patients. Tumor size ≥4 cm in breast cancer is a negative predictor of prognosis.

Auranofin-Loaded Chitosan Nanoparticles Demonstrate Potency against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) remains a clinical challenge due to molecular, metabolic, and genetic heterogeneity as well as the lack of validated drug targets. Thus, therapies or delivery paradigms are needed. Gold-derived compounds including the FDA-approved drug, auranofin have shown promise as effective anticancer agents against several tumors. To improve the solubility and bioavailability of auranofin, we hypothesized that the nanodelivery of auranofin using biodegradable chitosan modified polyethylene glycol (PEG) nanoparticles (NPs) will enhance anticancer activity against TNBC by comparing the best nanoformulation with the free drug. The selection of the nanoformulation was based on synthesis of various chitosan PEG copolymers via formaldehyde-mediated engraftment of PEG onto chitosan to form [chitosan-g-PEG] copolymer. Furthermore, altered physiochemical properties of the copolymer was based on the formaldehyde ratio towards nanoparticles (CP 1-4 NPs). Following the recruitment of PEG onto the chitosan polymer surface, we explored how this process influenced the stiffness of the nanoparticle using atomic force microscopy (AFM), a factor crucial for in vitro and in vivo studies. Our objective was to ensure the full functionality and inherent properties of chitosan as the parent polymer was maintained without allowing PEG to overshadow chitosan's unique cationic properties while improving solubility in neutral pH. Hence, CP 2 NP was chosen. To demonstrate the efficacy of CP 2 NP as a good delivery carrier for auranofin, we administered a dose of 3 mg/kg of auranofin, in contrast to free auranofin, which was given at 5 mg/kg. In vivo studies revealed the potency of encapsulated auranofin against TNBC cells with a severe necrotic effect following treatment superior to that of free auranofin. In conclusion, chitosan-g-PEG nanoparticles have the potential to be an excellent delivery system for auranofin, increasing its effectiveness and potentially reducing its clinical limitations.

Molecular pathology in breast disease: diagnostic, prognostic, and therapeutic tools

Molecular testing in breast cancer gained increasing attention and importance as specific molecular results can tailor not only oncological decisions on systemic adjuvant or neoadjuvant or in metastatic setting, but increasingly serve in diagnostic routine histopathological services to differentiate between morphologically overlapping or ambiguous histological pictures. Diagnostic tools involve in most cases a broad spectrum of immunohistochemical panels, followed by entity-specific in situ hybridization probes and in given cases NGS-based sequencing. Workflow of which methodology is applied and in which order depends on the specific entity resp. on the given differential diagnosis in question. Regarding prognostic/predictive molecular testing, the choice of assay and the workflow are based on clinical algorithms and on the evidence of targeted therapies following the molecular alterations. In this review paper, we aim to address the use of molecular technics in [1] the histological diagnostic setting (such as subtyping of invasive carcinomas/malignant spindle cell tumors and sarcomas and some B3 lesions) and [2] in the context of adjuvant or neoadjuvant or other clinical settings with special focus of targeted therapies.

PD-L1 testing in metastatic triple-negative breast cancer: Interobserver and interplatform reproducibility of CE-IVD assays for CPS and IC scores

PD-L1 test is recommended in different types of tumors to select patients eligible for immune checkpoint inhibitors (ICI) therapy. Several factors make this test challenging in metastatic triple-negative breast cancer (mTNBC). Different assays and platforms are available, each associated with distinct scoring systems and threshold values specific to the ICI compound used, i.e. CPS≥10 for pembrolizumab and IC ≥ 1 % for atezolizumab. Our objective was to assess the consistency of PD-L1 testing in mTNBC by examining interobserver and interassay reproducibility. We assessed n = 60 mTNBC samples for PD-L1 testing using 22C3 pharmDx assay on a Dako Autostainer Link 48 and VENTANA PD-L1 (SP263) on a Ventana BenchMark Ultra. Additionally, a subset of n = 19 samples was tested using the SP142 assay, also on the Ventana BenchMark Ultra. CPS with both 22C3 and SP263 was independently evaluated by five pathologists, all certified PD-L1 trainers. The IC with SP142 was assessed by three of these pathologists, who have particular expertise in breast pathology. Following the computation of the intraclass correlation coefficient (ICC) for each assay and their respective thresholds, we assessed the agreement between different raters and assays using Fleiss's κ, with a 95 % confidence interval (CI). Overall, we observed a significant (p < 0.001) ICC with both CPS assays [22C3 = 0.939 (CI:0.913-0.96); SP263 = 0.972 (CI:0.96-0.982); combined 22C3-SP263 = 0.909 (CI:0.874-0.938)]. Fleiss's κ confirmed an almost perfect agreement among pathologists and assays: 22C3 = 0.938 (CI:0.857-1.018); SP263 = 0.972 (CI:0.890-1.052); combined 22C3-SP263 = 0.907 (CI:0.869-0.945). Perfect inter-rater agreement was reached considering IC. This study establishes the reliability of assessing CPS in mTNBC using either the 22C3 pharmDx, as employed in the KEYNOTE studies, or the VENTANA SP263 assay. Each assay must be used on its designated platform, namely the Dako for 22C3 pharmDx and the Ventana for VENTANA SP263. It is important to remark that CPS and IC identify different patient cohorts and, therefore, are not interchangeable.

Bispecific antibodies revolutionizing breast cancer treatment: a comprehensive overview

Breast cancer (BCa) is known as a complex and prevalent disease requiring the development of novel anticancer therapeutic approaches. Bispecific antibodies (BsAbs) have emerged as a favorable strategy for BCa treatment due to their unique ability to target two different antigens simultaneously. By targeting tumor-associated antigens (TAAs) on cancer cells, engaging immune effector cells, or blocking critical signaling pathways, BsAbs offer enhanced tumor specificity and immune system involvement, improving anti-cancer activity. Preclinical and clinical studies have demonstrated the potential of BsAbs in BCa. For example, BsAbs targeting human epidermal growth factor receptor 2 (HER2) have shown the ability to redirect immune cells to HER2-positive BCa cells, resulting in effective tumor cell killing. Moreover, targeting the PD-1/PD-L1 pathway by BsAbs has demonstrated promising outcomes in overcoming immunosuppression and enhancing immune-mediated tumor clearance. Combining BsAbs with existing therapeutic approaches, such as chemotherapy, targeted therapies, or immune checkpoint inhibitors (ICIs), has also revealed synergistic effects in preclinical models and early clinical trials, emphasizing the usefulness and potential of BsAbs in BCa treatment. This review summarizes the latest evidence about BsAbs in treating BCa and the challenges and opportunities of their use in BCa.

Advances in Early Breast Cancer Risk Profiling: From Histopathology to Molecular Technologies

Early breast cancer (BC) is the definition applied to breast-confined tumors with or without limited involvement of locoregional lymph nodes. While risk stratification is essential for guiding clinical decisions, it can be a complex endeavor in these patients due to the absence of comprehensive guidelines. Histopathological analysis and biomarker assessment play a pivotal role in defining patient outcomes. Traditional histological criteria such as tumor size, lymph node involvement, histological type and grade, lymphovascular invasion, and immune cell infiltration are significant prognostic indicators. In addition to the hormone receptor, HER2, and-in specific scenarios-BRCA1/2 testing, molecular subtyping through gene expression profiling provides valuable insights to tailor clinical decision-making. The emergence of "omics" technologies, applicable to both tissue and liquid biopsy samples, has broadened our arsenal for evaluating the risk of early BC. However, a pressing need remains for standardized methodologies and integrated pathological models that encompass multiple analytical dimensions. In this study, we provide a detailed examination of the existing strategies for early BC risk stratification, intending to serve as a practical guide for histopathologists and molecular pathologists.

Triple-negative breast cancer: from none to multiple therapeutic targets in two decades

Triple-negative breast cancers (TNBCs) are more likely to occur in younger patients and have a poor prognosis. They are highly heterogeneous tumors consisting of different molecular subtypes. The only common characteristic among them is the absence of targets for endocrine therapy and human epidermal growth factor receptor 2 (HER2) blockade. In the past two decades, there has been an increased understanding of these tumors from a molecular perspective, leading to their stratification according to new therapeutic strategies. TNBC has ushered breast carcinomas into the era of immunotherapy. The higher frequency of germline BRCA mutations in these tumors enables targeting this repair defect by drugs like PARP inhibitors, resulting in synthetic lethality in neoplastic cells. Additionally, we have the identification of new molecules to which this generation of smart drugs, such as antibody-drug conjugates (ADCs), are directed. In this review, we will discuss the trajectory of this knowledge in a systematic manner, presenting the molecular bases, therapeutic possibilities, and biomarkers.

Advancing the PD-L1 CPS test in metastatic TNBC: Insights from pathologists and findings from a nationwide survey

Pembrolizumab has received approval as a first-line treatment for unresectable/metastatic triple-negative breast cancer (mTNBC) with a PD-L1 combined positive score (CPS) of ≥ 10. However, assessing CPS in mTNBC poses challenges. Firstly, it represents a novel analysis for breast pathologists. Secondly, the heterogeneity of PD-L1 expression in mTNBC further complicates the assessment. Lastly, the lack of standardized assays and staining platforms adds to the complexity. In KEYNOTE trials, PD-L1 expression was evaluated using the IHC 22C3 pharmDx kit as a companion diagnostic test. However, both the 22C3 pharmDx and VENTANA PD-L1 (SP263) assays are validated for CPS assessment. Consequently, assay-platform choice, staining conditions, and scoring methods can significantly impact the testing outcomes. This consensus paper aims to discuss the intricacies of PD-L1 CPS testing in mTNBC and provide practical recommendations for pathologists. Additionally, we present findings from a nationwide Italian survey elucidating the state-of-the-art in PD-L1 CPS testing in mTNBC.

Computational pathology to improve biomarker testing in breast cancer: how close are we?

The recent advancements in breast cancer precision medicine have highlighted the urgency for the precise and reproducible characterization of clinically actionable biomarkers. Despite numerous standardization efforts, biomarker testing by conventional methodologies is challenged by several issues such as high inter-observer variabilities, the spatial heterogeneity of biomarkers expression, and technological heterogeneity. In this respect, artificial intelligence-based digital pathology approaches are being increasingly recognized as promising methods for biomarker testing and subsequently improved clinical management. Here, we provide an overview on the most recent advances for artificial intelligence-assisted biomarkers testing in breast cancer, with a particular focus on tumor-infiltrating lymphocytes, programmed death-ligand 1, phosphatidylinositol-3 kinase catalytic alpha, and estrogen receptor 1. Challenges and solutions for this integrative analysis in pathology laboratories are also provided.

Immune microenvironment dynamics in breast cancer during pregnancy: impact of gestational age on tumor-infiltrating lymphocytes and prognosis

Background

Breast cancer during pregnancy (PrBC) is a rare condition known for its aggressive clinical behavior. The presence of tumor-infiltrating lymphocytes (TILs) has been shown to have a significant impact on the prognosis of these patients. Despite some biological characteristics of the tumor that may differ depending on the gestational age, little is known about the dynamics of the immune landscape within the tumor microenvironment (TME) in PrBC. Therefore, in this study, our objective was to gain comprehensive insights into the relationship between gestational age at breast cancer diagnosis and the composition of the TME.

Methods

n = 108 PrBC were selected from our institutional registry and categorized based on the gestational age by trimester. For all cases, TILs were profiled according to the International TILs Working Group recommendations, and subtyped by CD4, CD8, and forkhead box P3 (FOXP3) immunohistochemistry. PD-L1 was tested according to the combined positive score (CPS) using the IHC 22C3 pharmDx assay, with a cutoff value of ≥10 for positivity. The statistical approach encompassed Fisher's and Chi-squared tests, with appropriate adjustments for multiple comparisons, logistic regression models, and survival analyses based on the Kaplan-Meier method.

Results

The proportion of patients with poorly differentiated (G3) neoplasms increased as the gestational age advanced (first trimester, n = 25, 56.8%; second trimester, n = 27, 69.2%; third trimester, n = 21, 87.5%; p = 0.03). The histologic subtypes as well as the hormone receptor (HR) and HER2 status did not show significant changes across different pregnancy trimesters. In the HR+/HER2- subtype, there was a higher proportion of tumors with high/moderate TILs in the early phases of pregnancy, similar to FOXP3 expression (TILs: first trimester, n = 10, 35.7%; second trimester, n = 2, 10.5%; third trimester, n = 0; p = 0.02; FOXP3: first trimester, n = 10, 40%; second trimester, n = 3, 15.8%; third trimester, n = 0; p = 0.03). The median follow-up for our cohort was 81 months. Patients who relapsed after a breast cancer diagnosis during the first trimester were more frequently PD-L1-negative, unlike those with no disease recurrence (n = 9, 100% vs. n = 9, 56.3%; p = 0.03; hormone therapy and n = 9, 100% vs. n = 7, 53.9%; p = 0.02; chemotherapy). No statistically significant differences were seen among the three trimesters in terms of survival outcome.

Conclusion

The TME dynamics of HR+/HER2- PrBC vary based on gestational age, suggesting that immune tolerance expression during later gestational age could explain the increased aggressiveness of tumors diagnosed at that stage.

Immune Biomarkers in Triple-Negative Breast Cancer: Improving the Predictivity of Current Testing Methods

Triple-negative breast cancer (TNBC) poses a significant challenge in terms of prognosis and disease recurrence. The limited treatment options and the development of resistance to chemotherapy make it particularly difficult to manage these patients. However, recent research has been shifting its focus towards biomarker-based approaches for TNBC, with a particular emphasis on the tumor immune landscape. Immune biomarkers in TNBC are now a subject of great interest due to the presence of tumor-infiltrating lymphocytes (TILs) in these tumors. This characteristic often coincides with the presence of PD-L1 expression on both neoplastic cells and immune cells within the tumor microenvironment. Furthermore, a subset of TNBC harbor mismatch repair deficient (dMMR) TNBC, which is frequently accompanied by microsatellite instability (MSI). All of these immune biomarkers hold actionable potential for guiding patient selection in immunotherapy. To fully capitalize on these opportunities, the identification of additional or complementary biomarkers and the implementation of highly customized testing strategies are of paramount importance in TNBC. In this regard, this article aims to provide an overview of the current state of the art in immune-related biomarkers for TNBC. Specifically, it focuses on the various testing methodologies available and sheds light on the immediate future perspectives for patient selection. By delving into the advancements made in understanding the immune landscape of TNBC, this study aims to contribute to the growing body of knowledge in the field. The ultimate goal is to pave the way for the development of more personalized testing strategies, ultimately improving outcomes for TNBC patients.

Characterization of the immune environment in pregnancy-associated breast cancer

Pregnancy-associated breast cancer (PrBC) is a rare and clinically challenging condition. Specific immune mechanisms and pathways are involved in maternal-fetal tolerance and tumor-host immunoediting. The comprehension of the molecular processes underpinning this immune synergy in PrBC is needed to improve patients' clinical management. Only a few studies focused on the immune biology of PrBC and attempted to identify bona fide biomarkers. Therefore, clinically actionable information remains extremely puzzling for these patients. In this review article, we discuss the current knowledge on the immune environment of PrBC, in comparison with pregnancy-unrelated breast cancer and in the context of maternal immune changes during pregnancy. A particular emphasis is given to the actual role of potential immune-related biomarkers for PrBC clinical management.

Breast Cancer with Brain Metastasis: Molecular Insights and Clinical Management

Breast cancer is the most frequently diagnosed malignancy worldwide and the leading cause of cancer-related death among women. Brain metastases are a primary contributor to mortality, as they often go undetected until late stages due to their dormant nature. Moreover, the clinical management of brain metastases is complicated by the relevant issue of blood-brain barrier penetration. The molecular pathways involved in the formation, progression, and colonization of primary breast tumors and subsequent brain metastases are diverse, posing significant hurdles due to the heterogeneous nature of breast cancer subtypes. Despite advancements in primary breast cancer treatments, the prognosis for patients with brain metastases remains poor. In this review, we aim to highlight the biological mechanisms of breast cancer brain metastases by evaluating multi-step genetic pathways and to discuss currently available and emerging treatment strategies to propose a prospective overview of the management of this complex disease.

The molecular landscape of breast mucoepidermoid carcinoma

Mucoepidermoid carcinoma (MEC) of the breast is an extremely rare salivary gland-type tumor characterized by epidermoid, basaloid, intermediate, and/or mucinous cells arranged in solid and cystic patterns. Despite their triple-negative phenotype, breast MECs are generally considered low-risk malignancies but their biology is largely unexplored; therefore, guidelines for clinical management are lacking. Here, we sought to characterize the molecular landscape of breast MECs. Thirteen cases were histologically reviewed, characterized for tumor-infiltrating lymphocytes (TILs), and were subjected to immunohistochemistry for programmed death-ligand 1 (PD-L1, clone 22C3), EGFR, and amphiregulin (AREG). Rearrangements in MAML2 and EWSR1 were investigated by fluorescent in situ hybridization. Targeted next-generation sequencing of 161 genes was performed on eight cases. Most MECs had low histological grade (n = 10, 77%), with the presence of TILs (n = 9/12; 75%) and PD-L1 combined positive score ranging from 10 to 20 (n = 4/6; 67%). All cases showed EGFR and AREG overexpression and were fusion negative. Enrichment of genetic alterations was observed in PI3K/AKT/mTOR and cell cycle regulation pathways, while only one case harbored TP53 mutations. This is the first study providing extensive molecular data on breast MECs and the largest collection of cases available to date in the literature. Breast MECs lack TP53 mutations found in high-grade forms of triple-negative breast cancers and MAML2 or EWSR1 rearrangements pathognomonic of salivary MECs. Triple-negativity and PD-L1 positivity suggest a window of opportunity for immunotherapy in these patients. The EGFR/AREG axis activation, coupled with the mutational patterns in PI3K/AKT/mTOR and cell cycle pathways warrants caution in considering MECs as low-risk neoplasms.

Kinesin family member 3A induces related diseases via wingless-related integration site/β-catenin signaling pathway

Kinesin family member 3A is an important motor protein that participates in various physiological and pathological processes, including normal tissue development, homeostasis maintenance, tumor infiltration, and migration. The wingless-related integration site/β-catenin signaling pathway is essential for critical molecular mechanisms such as embryonic development, organogenesis, tissue regeneration, and carcinogenesis. Recent studies have examined the molecular mechanisms of kinesin family member 3A, among which the wingless-related integration site/β-catenin signaling pathway has gained attention. The interaction between kinesin family member 3A and the wingless-related integration site/β-catenin signaling pathway is compact and complex but is fascinating and worthy of further study. The upregulation and downregulation of kinesin family member 3A influence many diseases and patient survival through the wingless-related integration site/β-catenin signaling pathway. Therefore, this review mainly focuses on describing the kinesin family member 3A and wingless-related integration site/β-catenin signaling pathways and their associated diseases.

Osteoclast-like stromal giant cells in breast cancer likely belong to the spectrum of immunosuppressive tumor-associated macrophages

Background: Breast cancer with osteoclast-like stromal giant cells (OSGC) is an exceedingly rare morphological pattern of invasive breast carcinoma. The tumor immune microenvironment (TIME) of these tumors is populated by OSGC, which resemble osteoclasts and show a histiocytic-like immunophenotype. Their role in breast cancer is unknown. The osteoclast maturation in the bone is regulated by the expression of cytokines that are also present in the TIME of tumors and in breast cancer tumor-associated macrophages (TAMs). TAMs-mediated anti-tumor immune pathways are regulated by miRNAs akin to osteoclast homeostasis. Here, we sought to characterize the different cellular compartments of breast cancers with OSGC and investigate the similarities of OSGC with tumor and TIME in terms of morphology, protein, and miRNA expression, specifically emphasizing on monocytic signatures.

Methods and Results: Six breast cancers with OSGC were included. Tumor-infiltrating lymphocytes (TILs) and TAMs were separately quantified. The different cellular populations (i.e., normal epithelium, cancer cells, and OSGC) were isolated from tissue sections by laser-assisted microdissection. After RNA purification, 752 miRNAs were analyzed using a TaqMan Advanced miRNA Low-Density Array for all samples. Differentially expressed miRNAs were identified by computing the fold change (log2Ratio) using the Kolmogorov-Smirnov test and p values were corrected for multiple comparisons using the false discovery rate (FDR) approach. As a similarity analysis among samples, we used the Pearson test. The association between pairs of variables was investigated using Fisher exact test. Classical and non-classical monocyte miRNA signatures were finally applied. All OSGC displayed CD68 expression, TILs (range, 45–85%) and high TAMs (range, 35–75%). Regarding the global miRNAs profile, OSGC was more similar to cancer cells than to non-neoplastic ones. Shared deregulation of miR-143-3p, miR-195-5p, miR-181a-5p, and miR-181b-5p was observed between OSGC and cancer cells. The monocyte-associated miR-29a-3p and miR-21-3p were dysregulated in OSGCs compared with non-neoplastic or breast cancer tissues.

Conclusion: Breast cancers with OSGC have an activated TIME. Shared epigenetic events occur during the ontogenesis of breast cancer cells and OSGC but the innumophenotype and miRNA profiles of the different cellular compartmens suggest that OSGC likely belong to the spectrum of M2 TAMs.

Breast Cancer during Pregnancy as a Special Type of Early-Onset Breast Cancer: Analysis of the Tumor Immune Microenvironment and Risk Profiles

Breast cancer during pregnancy (PrBC) is a rare tumor with only a little information on its immune landscape. Here, we sought to characterize the cellular composition of the tumor microenvironment (TME) of PrBC and identify its differences from early-onset breast cancer (EOBC) in non-pregnant women. A total of 83 PrBC and 89 EOBC were selected from our Institutional registry and subjected to tumor-infiltrating lymphocytes (TILs) profiling and immunohistochemistry for CD4, CD8, forkhead box P3 (FOXP3), and programmed death-ligand 1 (PD-L1) (clone 22C3). A significantly lower frequency of hormone receptor (HR)-positive tumors was observed in PrBC. The prevalence of low/null PD-L1 and CD8+TILs was higher in PrBC than in the controls, specifically in HR+/HER2– breast cancers. PrBC had a significantly higher risk of relapse and disease-related death, compared to EOBC. The presence of TILs and each TIL subpopulation were significantly associated with disease relapse. Moreover, the death rate was higher in PrBC with CD8+ TILs. The TME of PrBC is characterized by specific patterns of TIL subpopulations with significant biological and prognostic roles. Routine assessment of TILs and TILs subtyping in these patients would be a valid addition to the pathology report that might help identify clinically relevant subsets of women with PrBC.

Atlas of PD-L1 for Pathologists: Indications, Scores, Diagnostic Platforms and Reporting Systems

BACKGROUND

Innovative drugs targeting the PD1/PD-L1 axis have opened promising scenarios in modern cancer therapy. Plenty of assays and scoring systems have been developed for the evaluation of PD-L1 immunohistochemical expression, so far considered the most reliable therapeutic predictive marker.

METHODS

By gathering the opinion of acknowledged experts in dedicated fields of pathology, we sought to update the currently available evidence on PD-L1 assessment in various types of tumors.

RESULTS

Robust data were progressively collected for several anatomic districts and leading international agencies to approve specific protocols: among these, TPS with 22C3, SP142 and SP263 clones in lung cancer; IC with SP142 antibody in breast, lung and urothelial tumors; and CPS with 22C3/SP263 assays in head and neck and urothelial carcinomas. On the other hand, for other malignancies, such as gastroenteric neoplasms, immunotherapy has been only recently introduced, often for particular histotypes, so specific guidelines are still lacking.

CONCLUSIONS

PD-L1 immunohistochemical scoring is currently the basis for allowing many cancer patients to receive properly targeted therapies. While protocols supported by proven data are already available for many tumors, dedicated studies and clinical trials focusing on harmonization of the topic in other still only partially explored fields are surely yet advisable.

Assessment of Cone-Beam Breast Computed Tomography for Predicting Pathologic Response to Neoadjuvant Chemotherapy in Breast Cancer: A Prospective Study

Background

Response surveillance of neoadjuvant chemotherapy is needed to facilitate treatment decisions. We aimed to assess the imaging features of cone-beam breast computed tomography (CBBCT) for predicting the pathologic response of breast cancer after neoadjuvant chemotherapy.

Methods

This prospective study included 81 women with locally advanced breast cancer who underwent neoadjuvant chemotherapy from August 2017 to January 2021. All patients underwent CBBCT before treatment, and 55 and 65 patients underwent CT examinations during the midtreatment (3 cycles) and late-treatment phases (7 cycles), respectively. Clinical information and quantitative parameters such as the diameter, volume, surface area, and CT density were compared between pathologic responders and nonresponders using the T–test and the Mann–Whitney U test. The performance of meaningful parameters was evaluated with the receiver operating characteristic curve, sensitivity, and specificity.

Results

The quantitative results for the segmented volume, segmented surface area, segmented volume reduction, maximum enhancement ratio, wash-in rate and two-minute enhancement value in the mid- and late-treatment periods had predictive value for pathologic complete response. The area under the curve for the prediction model after multivariate regression analysis was 0.874.

Conclusion

After comparing the outcomes of each timepoint, mid- and late-treatment parameters can be used to predict pathologic outcome. The late-treatment parameters showed significant value with a predictive model.

CAR-T cell therapy for triple-negative breast cancer and other solid tumors: preclinical and clinical progress

INTRODUCTION

Most breast cancer-related deaths arise from triple-negative breast cancer (TNBC). Molecular heterogeneity, aggressiveness and the lack of effective therapies are major hurdles to therapeutic progress. Chimeric antigen receptor (CAR)-T cells have emerged as a promising immunotherapeutic strategy in TNBC. This approach combines the antigen specificity of an antibody with the effector function of T cells.

AREAS COVERED

This review examines the opportunities provided by CAR-T cell therapies in solid tumors. Emerging targets, ongoing clinical trials, and prospective clinical implications in TNBC are considered later. An emphasis is placed on the key challenges and possible solutions for this therapeutic approach.

EXPERT OPINION

A challenge for CAR-T cell therapy is the selection of the optimal targets to minimize on-target/off-tumor toxicity. Tumor escape via antigen loss and intrinsic heterogeneity is a further hurdle. TROP2, GD2, ROR1, MUC1 and EpCAM are promising targets. Persistence and trafficking to tumor cells may be enhanced by the implementation of CARs with a chemokine receptor and/or constitutively activated interleukin receptors. Fourth-generation CARs (TRUCKs) may redirect T-cells for universal cytokine-mediated killing. Combinatorial approaches and the application of CARs to other immune cells could revert the suppressive immune environment that characterizes solid neoplasms.