Project description:The human HCC1806 cell line is frequently used as a preclinical model for triple negative breast cancer (TNBC). Given that dysregulated epigenetic mechanisms are involved in cancer pathogenesis, emerging therapeutic strategies target chromatin regulators, such as histone deacetylases. A comprehensive understanding of the epigenome and transcription profiling in HCC1806 provides the framework for evaluating efficacy and molecular mechanisms of epigenetic therapies. Thus, to study the interplay of transcription and chromatin in the HCC1806 preclinical model, we performed nascent transcription profiling using Precision Run-On coupled to sequencing (PRO-seq). Additionally, we mapped the genome-wide locations for RNA polymerase II (Pol II), the histone variant H2A.Z, seven histone modifications, and CTCF using ChIP-exo. ChIP-exonuclease (ChIP-exo) is a refined version of ChIP-seq with near base pair precision mapping of protein-DNA interactions. In this Data Descriptor, we present detailed information on experimental design, data generation, quality control analysis, and data validation. We discuss how these data lay the foundation for future analysis to understand the relationship between the nascent transcription and chromatin.
Project description:Neoadjuvant pembrolizumab plus chemotherapy (P + CT) has emerged as a standard of care for stage II-III triple-negative breast cancer (TNBC). However, the best anthracycline-cyclophosphamide (AC) schedule remains to be determined. While the KEYNOTE-522 regimen employs AC every 3 weeks (q3w AC), previous studies have shown overall survival benefits of dose-dense regimens for early-stage breast cancer. The Neo-Real study (GBECAM-0123) is a real-world data effort evaluating patients with TNBC treated with neoadjuvant P + CT in ten cancer centers since July 2020. The objective of this analysis was to evaluate the effectiveness and safety of dose-dense AC (ddAC) versus q3w AC. Among 333 patients included until November 2023, 311 completed neoadjuvant therapy and 279 underwent surgery with pathology reports available; ddAC was used in 58.2% and q3w AC in 41.8% of the cases. Most patients (69.1%) had stage II TNBC. A pCR was observed in 65.4% with ddAC and 58.7% with q3w AC (P = 0.260), while RCB 0-1 occurred in 82.4% and 73.5%, respectively (P = 0.115). Patients with stage III disease had a numerically higher pCR with ddAC (59% vs 40%, P = 0.155), while pCR rates were similar regardless of AC regimen in stage II disease (66.6% vs 64.5%; P = 0.760). While no significant disparities in drug discontinuation was noted, ddAC showed a trend towards higher rates of grade ≥3 AE (40.5% vs. 30.7%, P = 0.092). The Neo-Real study could not rule out a difference between ddAC and q3w AC during neoadjuvant P + CT. The observation of a potentially higher pCR with ddAC in stage III disease warrants further investigation.
Project description:Triple-negative breast cancer (TNBC) is defined by the absence of estrogen receptor and progesterone receptor and human epidermal growth factor receptor 2 (HER2) overexpression. This malignancy, representing 15-20% of breast cancers, is a clinical challenge due to the lack of targeted treatments, higher intrinsic aggressiveness, and worse outcomes than other breast cancer subtypes. Immune checkpoint inhibitors have shown promising efficacy for early-stage and advanced TNBC, but this seems limited to a subgroup of patients. Understanding the underlying mechanisms that determine immunotherapy efficiency is essential to identifying which TNBC patients will respond to immunotherapy-based treatments and help to develop new therapeutic strategies. Emerging evidence supports that epigenetic alterations, including aberrant chromatin architecture conformation and the modulation of gene regulatory elements, are critical mechanisms for immune escape. These alterations are particularly interesting since they can be reverted through the inhibition of epigenetic regulators. For that reason, several recent studies suggest that the combination of epigenetic drugs and immunotherapeutic agents can boost anticancer immune responses. In this review, we focused on the contribution of epigenetics to the crosstalk between immune and cancer cells, its relevance on immunotherapy response in TNBC, and the potential benefits of combined treatments.
Project description:Camouflaged cell-membrane-based nanoparticles have been gaining increasing attention owing to their improved biocompatibility and immunomodulatory properties. Using nanoparticles prepared from the membranes of specific cell types, or fusions derived from different cells membranes, can improve their functional performance in several aspects. Here, we used cell membranes extracted from breast cancer cells and platelets to fabricate a hybrid-membrane vesicle fusion (cancer cell-platelet-fusion-membrane vesicle, CPMV) in which we loaded therapeutic microRNAs (miRNAs) for the treatment of triple-negative breast cancer (TNBC). We used a clinically scalable microfluidic platform for the fusion of cell membranes. The reconstitution process during synthesis allows for efficient loading of miRNAs into CPMVs. We systematically optimized the conditions for preparation of miRNA-loaded CPMVs and demonstrated their property of homing to source cells using in vitro experiments, and by therapeutic evaluation in vivo. In vitro, the CPMVs exhibited significant recognition of their source cells and avoided engulfment by macrophages. After systemic delivery in mice, the CPMVs showed a prolonged circulation time and site-specific accumulation at implanted TNBC-xenografts. The delivered antimiRNAs sensitized TNBCs to doxorubicin, resulting in an improved therapeutic response and survival rate. This strategy has considerable potential for clinical translation to improve personalized therapy for breast cancer and other malignancies.
Project description:Triple negative breast cancer (TNBC) is characterized by poor prognosis and a DNA hypomethylation profile. Withaferin A (WA) is a plant derived steroidal lactone which holds promise as a therapeutic agent for treatment of breast cancer (BC). We determined genome-wide DNA methylation changes in weakly-metastatic and aggressive, metastatic BC cell lines, following 72h treatment to a sub-cytotoxic concentration of WA. In contrast to the DNA demethylating agent 5-aza-2'-deoxycytidine (DAC), WA treatment of MDA-MB-231 cells rather tackles an epigenetic cancer network through gene-specific DNA hypermethylation of tumor promoting genes including ADAM metallopeptidase domain 8 (ADAM8), urokinase-type plasminogen activator (PLAU), tumor necrosis factor (ligand) superfamily, member 12 (TNFSF12), and genes related to detoxification (glutathione S-transferase mu 1, GSTM1), or mitochondrial metabolism (malic enzyme 3, ME3). Gene expression and pathway enrichment analysis further reveals epigenetic suppression of multiple cancer hallmarks associated with cell cycle regulation, cell death, cancer cell metabolism, cell motility and metastasis. Remarkably, DNA hypermethylation of corresponding CpG sites in PLAU, ADAM8, TNSF12, GSTM1 and ME3 genes correlates with receptor tyrosine-protein kinase erbB-2 amplification (HER2)/estrogen receptor (ESR)/progesterone receptor (PR) status in primary BC tumors. Moreover, upon comparing differentially methylated WA responsive target genes with DNA methylation changes in different clinical subtypes of breast cancer patients in the cancer genome atlas (TCGA), we found that WA silences HER2/PR/ESR-dependent gene expression programs to suppress aggressive TNBC characteristics in favor of luminal BC hallmarks, with an improved therapeutic sensitivity. In this respect, WA may represent a novel and attractive phyto-pharmaceutical for TNBC treatment.
Project description:BackgroundBreast cancer remains a major health problem in the world. Triple-negative breast cancer (TNBC) is an aggressive subtype with very poor prognosis. Up to now, the mechanism behind TNBC's activity is still unclear and no candidate drug target has been identified. Thus, it is of critical importance to elucidate the pathways in TNBC and identify the relevant biomarkers. Recent studies showed that ganglioside D3 synthase (GD3s) played a very important role in development of cancers. However, the physiological functions and associated pathways of GD3s in TNBC are still unclear.MethodsIn silico analysis of the expression of GD3s in TNBC was conducted using The Cancer Genome Atlas (TCGA) and Oncomine databases. The proliferation of breast cancer cells was measured by MTT assay, colony formation by the soft agar method, and migration and invasion using Boyden chamber inserts. The methylation level of the gene encoding GD3s, ST8SIA1, in specimens was assessed by qMS-PCR and in silico using the UCSC gene browser. Protein expression was examined via immunohistochemistry (IHC), qRT-PCR and Western immunoblotting.ResultsIn silico analysis showed a higher GD3s expression in ER- than ER+ breast cancers and GD3s was also highly expressed in TNBC compared to other types of breast cancers. The elevated GD3s expression in TNBC cells and tissues was associated with hypomethylation of the ST8SIA1 gene. Overexpression of GD3s in human breast cancer cells increased their proliferation, migration, invasion and colony formation ability. GD3s expression in breast cancers was closely associated with relapse-free survival (RFS) and overall survival (OS).ConclusionsIn summary, these results suggest that GD3s may be a potential biomarker and drug target in treatment of TNBC.
Project description:Immune checkpoint inhibitors (ICIs) have made a breakthrough in the systemic treatment for metastatic triple-negative breast cancer (TNBC) patients. However, results of phase II and III clinical trials assessing ICIs plus chemotherapy as neoadjuvant treatment were controversial and conflicting. We performed a meta-analysis aimed at assessing the Odds Ratio (OR) of the pathological complete response (pCR) rate in trials assessing neoadjuvant chemoimmunotherapy in TNBC. According to our results, the use of neoadjuvant chemoimmunotherapy was associated with higher pCR (OR 1.95; 95% Confidence Intervals, 1.27–2.99). In addition, we highlighted that this benefit was observed regardless of PD-L1 status since the analysis reported a statistically significant and clinically meaningful benefit in both PD-L1 positive and PD-L1 negative patients. These findings further support the exploration of the role of ICIs plus chemotherapy in early-stage TNBC, given the potentially meaningful clinical impact of these agents. Further studies aimed at more deeply investigating this emerging topic in breast cancer immunotherapy are warranted.
Project description:BackgroundThe selection of appropriate chemotherapy backbone agents in combination with neoadjuvant immunotherapy for triple-negative breast cancer (TNBC) remains unclear. Herein, we aimed to evaluate the efficacy and safety of anthracycline-free and anthracycline-containing regimens coupled with neoadjuvant immunotherapy.MethodThis retrospective study included 87 patients with TBNC who received neoadjuvant immunotherapy combined with various chemotherapy regimens at three research centers from November 2020 to November 2023. The primary objective was pathological complete response (pCR), while secondary objectives included overall response rates, event-free survival (EFS), and the incidence of adverse events. A subgroup analysis was performed to delineate patients who may substantially benefit from distinct therapeutic strategies.ResultsCoupled with immunotherapy, anthracycline-free regimens achieved comparable pCR rates (55.1 % vs. 51.4 %; Odds ratio, 1.16; 95 % confidence interval [CI], 0.49-2.74; p = 0.73) and EFS (Hazard ratio, 0.66; 95 % CI, 0.18-2.45; p = 0.53) to anthracycline-containing regimens. According to subgroup analyses, the tumor stage (p = 0.017) and lymph node stage (p = 0.011) exhibit contradictory predictive power for the pCR rate of anthracycline-free regimens when compared with that of anthracycline-containing regimens. Specifically, anthracycline-free regimens yielded significantly higher pCR rates in patients without lymph node metastasis than anthracycline-containing regimens (p = 0.021). Pooled analyses further confirmed the results of both total and subgroup analyses. Most adverse events were grades 1-2, and no new adverse reactions were observed.ConclusionAnthracycline-free neoadjuvant chemotherapy regimens could serve as an effective and safe alternative immunotherapy partner for patients with TNBC, particularly in those without lymph node metastasis.
Project description:It is a great challenge to effectively treat triple-negative breast cancer (TNBC) due to lack of therapeutic targets and drug resistance of systemic chemotherapy. Rational design of nanomedicine with good hemocompatibility is urgently desirable for combination therapy of TNBC. Herein, an erythrocyte membrane-camouflaged fluorescent covalent organic framework (COF) loaded with an NO donor (hydroxyurea, Hu), glucose oxidase (GOx) and cytosine-phosphate-guanine oligonucleotides (CPG) (COF@HGC) was developed for imaging-guided starving/nitric oxide (NO)/immunization synergistic treatment of TNBC. The substances of HGC are easily co-loaded onto the COF due to the ordered pore structure and large surface area. And a folic acid-modified erythrocyte membrane (FEM) is coated on the surface of COF@HGC to improve targeted therapy and haemocompatibility. When COF@HGC@FEM is internalized into tumor cells, hemoglobin (Hb) on FEM and GOx loaded on the COF can trigger cascade reactions to kill tumor cells due to the simultaneous production of NO and exhaustion of glucose. Meanwhile, the COF with excellent fluorescence properties can be used as a self-reporter for bioimaging. Furthermore, the CPG can reprogram tumor-associated macrophages from tumor-supportive phenotype to anti-tumor phenotype and enhance immunotherapy. Through the "three-in-one" strategy, the biomimetic nanoplatform can effectively inhibit tumor growth and reprogram the tumor immunosuppression microenvironment in the TNBC mouse model.
Project description:Doxorubicin (DOX) is a chemotherapy agent commonly used to treat triple-negative breast cancer (TNBC), but it has insufficient efficacy against the disease and considerable toxicity due to its off-target delivery. To improve the specificity of DOX for TNBC, we encapsulated it in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) coated with antibodies against Frizzled7 (FZD7), a receptor that is overexpressed on TNBC cells and which is a key activator of the Wnt signaling pathway. In vitro studies show that DOX encapsulation does not hinder its ability to localize to the nucleus in human TNBC cell cultures and that DOX delivered via NPs induces apoptosis and DNA damage via H2A.X phosphorylation to the same degree as freely delivered DOX. FZD7-targeted NPs delivering DOX caused significantly greater inhibition of metabolic activity and led to a smaller cell population following treatment when compared to freely delivered DOX or DOX-loaded NPs coated only with poly(ethylene glycol) (PEG). The FZD7 antibodies additionally provided significant levels of Wnt pathway inhibition, as demonstrated by an increase in β-catenin phosphorylation, indicative of β-catenin destruction and downregulation. These results show that FZD7-targeted platforms have great promise for improving the therapeutic window of otherwise toxic chemotherapies like DOX in TNBC and other cancers that display the overexpression of FZD7 receptors.