HER2-low heterogeneity between primary and paired recurrent/metastatic breast cancer: Implications in treatment and prognosis.

BACKGROUND: With the largest sample size to date, the authors' objective was to investigate the incidence of primary-to-metastatic human epidermal growth factor 2 (HER2) conversion and the predictors for such conversion. Moreover, no previous studies have evaluated the prognosis of patients who have negative HER2 expression (HER2-0) versus low HER2 expression (HER2-low) when HER2 status was assessed based on all recurrent/metastatic lesions. METHODS: The authors included 1299 patients who had available HER2 status of primary breast tumors and paired recurrent/metastatic lesions at Fudan University Shanghai Cancer Center and West China Hospital. RESULTS: In total, 370 patients (28.5%) experienced primary-to-metastatic HER2 conversion. Intrapatient intermetastasis spatial heterogeneity and temporal heterogeneity of HER2 were detected. When assessing HER2 based on recurrent/metastatic tumors, patients who had HER2-0 tumors had significantly shorter overall survival than those who had HER2-low tumors in the overall population and in the estrogen receptor (ER)-negative subgroup. However, when assessing HER2 based on primary tumors, there was no difference in overall survival between patients who had HER2-0 versus HER2-low tumors. Moreover, patients who had tumors that converted from HER2-0 to HER2-low had longer overall survival than those who had consistent HER2-0 status in the ER-negative subgroup. By combining four predictors (ER status, Ki67 index, biopsy site, and disease-free interval), the authors established the first prediction tool to estimate the probability of HER2-0 tumors converting to HER2-low/positive tumors. CONCLUSIONS: Intrapatient primary-to-metastatic and intermetastatic HER2 heterogeneity were observed in this large-scale cohort study. When evaluating HER2 based on recurrent/metastatic tumors, an overall survival difference was observed between patients who had HER2-0 versus HER2-low, recurrent/metastatic breast tumors. The developed prediction tool might help clinicians screen out patients with primary HER2-0 tumors that have a high probability of HER2 status conversion and recommend them for re-biopsy, thus helping to screen out candidate patients for trastuzumab deruxtecan treatment.

HS-10352 in hormone receptor-positive, HER2-negative advanced breast cancer: A phase 1 dose-escalation trial.

BACKGROUND: Approximately 40% of patients with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) exhibit PIK3CA mutations. AIMS: This study aims to evaluate the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of HS-10352, a selective PI3Kα inhibitor, in this patient population. MATERIALS AND METHODS: Conducted as a phase 1 dose-escalation trial, HS-10352 was administered orally once-daily (QD) at dose levels of 2, 4, 6, and 8 mg. The primary endpoints were dose-limiting toxicity (DLT) and the maximum tolerated dose (MTD). This study is registered at ClinicalTrials.gov (NCT04631835). RESULTS: Between August 2020 and March 2022, a total of 18 female patients were enrolled. DLT, manifested as hyperglycemia, occurred in two patients in the 8 mg QD group, establishing an MTD of 6 mg QD. The most common treatment-related adverse events were hyperglycemia (88.9%) and weight loss (61.3%). In the 6 mg QD group, four patients (66.7%) had a partial response (PR), and one (16.7%) had stable disease (SD). Among the four patients with PIK3CA mutated tumors in this dosage group, three (75.0%) had PR and one (25.0%) had SD. The median progression-free survival was not reached (95% confidence interval, 11.1-NA). DISCUSSION AND CONCLUSION: HS-10352 at 6 mg QD was well-tolerated in patients with HR-positive, HER2-negative ABC, and showed preliminary antitumor activity in patients with PIK3CA mutated tumors. These findings support the further clinical development of HS-10352.

Comprehensive analysis of cancer of unknown primary and recommendation of a histological and immunohistochemical diagnostic strategy from China.

BACKGROUND: Previous studies on cancer of unknown primary (CUP) mainly focus on treatment and prognosis in western populations and lacked clinical evaluation of different IHC markers, so this study aimed to evaluate characteristics of CUP and recommend a diagnostic strategy from a single center in China. METHODS AND RESULTS: Data of 625 patients with CUP were retrospectively collected and reviewed. The patients ranged in age from 20 to 91 years, with a female-to-male ratio of 1.3:1. The predominant histological type was poor or undifferentiated adenocarcinomas (308; 49.3%). The results of Canhelp-Origin molecular testing for the identification of the tissue of origin in 262 of 369 patients (71.0%) were considered predictable (similarity score > 45), with the most common predicted primary tumor site being the breast (57, 21.8%). Unpredictable molecular results correlated with more aggressive clinical parameters and poor survival. Thee positivity rates of several targeted antibodies (GATA3, GCDFP15, TTF1, Napsin A, and PAX8), based on the clinically predicted site, were lower than those reported for the corresponding primary tumors. Nonetheless, TRPS1 and INSM1 were reliable markers of predicted breast carcinoma (75.0%) and neuroendocrine tumors (83.3%), respectively. P16 expression, as well as HPV and EBER testing contributed significantly to the diagnosis of squamous cell carcinomas. Survival analysis revealed that older ages (> 57), ≥ 3 metastatic sites, non-squamous cell carcinomas, bone/liver/lung metastases, unpredictable molecular results, and palliative treatment correlated with poor overall survival. CONCLUSIONS: We recommend a CUP diagnostic strategy involving the use of targeted antibody panels as per histological findings that is potentially applicable in clinical practice. The markers TRPS1, INSM1, and P16 expression, as well as HPV and EBER testing are particularly valuable in this aspect. Molecular testing is also predictive of survival rates.

Pretreatment 18F-FDG uptake heterogeneity may predict treatment outcome of combined Trastuzumab and Pertuzumab therapy in patients with metastatic HER2 positive breast cancer.

OBJECTIVE: Intra-tumoral heterogeneity of 18F-fluorodeoxyglucose (18F-FDG) uptake has been proven to be a surrogate marker for predicting treatment outcome in various tumors. However, the value of intra-tumoral heterogeneity in metastatic Human epidermal growth factor receptor 2(HER2) positive breast cancer (MHBC) remains unknown. The aim of this study was to evaluate 18F-FDG uptake heterogeneity to predict the treatment outcome of the dual target therapy with Trastuzumab and Pertuzumab(TP) in MHBC. METHODS: Thirty-two patients with MHBC who underwent 18F-FDG positron emission tomography/computed tomography (PET/CT) scan before TP were enrolled retrospectively. The region of interesting (ROI) of the lesions were drawn, and maximum standard uptake value (SUVmax), mean standard uptake value (SUVmean), total lesion glycolysis (TLG), metabolic tumor volume (MTV) and heterogeneity index (HI) were recorded. Correlation between PET/CT parameters and the treatment outcome was analyzed by Spearman Rank Test. The ability to predict prognosis were determined by time-dependent survival receiver operating characteristic (ROC) analysis. And the survival analyses were then estimated by Kaplan-Meier method and compared by log-rank test. RESULTS: The survival analysis showed that HI50% calculated by delineating the lesion with 50%SUVmax as threshold was a significant predictor of patients with MHBC treated by the treatment with TP. Patients with HI50% (≥ 1.571) had a significantly worse prognosis of progression free survival (PFS) (6.87 vs. Not Reach, p = 0.001). The area under curve (AUC), the sensitivity and the specificity were 0.88, 100% and 63.6% for PFS, respectively. CONCLUSION: 18F-FDG uptake heterogeneity may be useful for predicting the prognosis of MHBC patients treated by TP.

Pyrotinib plus capecitabine for trastuzumab-resistant, HER2-positive advanced breast cancer (PICTURE): a single-arm, multicenter phase 2 trial.

BACKGROUND: Patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer and primary resistance to trastuzumab have a poor clinical outcome and lack good evidence to inform clinical decision. This study investigated the efficacy and safety of pyrotinib plus capecitabine in this population. METHODS: This phase 2 trial was conducted at 16 sites in China. Patients received oral pyrotinib 400 mg once daily and capecitabine 1000 mg/m2 twice a day on days 1-14 of each 21-day cycle until disease progression or intolerable toxicity. The primary endpoint was investigator-assessed progression-free survival (PFS). RESULTS: Between June 2019 and September 2021, 100 patients were enrolled with a median age of 51 years (range, 24-69). All patients had been treated with trastuzumab and 21 (21.0%) patients had prior use of pertuzumab. As of August 31, 2022, the median follow-up duration was 20.1 months (range, 1.3-38.2). The median PFS was 11.8 months (95% confidence interval [CI], 8.4-15.1), which crossed the pre-specified efficacy boundary of 8.0 months. The objective response rate was 70.0% (70/100), with a median duration of response of 13.8 months (95% CI, 10.2-19.3). The disease control rate was 87.0% (87/100). The median overall survival was not reached. The most common grade ≥ 3 treatment-emergent adverse event was diarrhea (24 [24.0%]). No treatment-related deaths occurred. CONCLUSIONS: Pyrotinib plus capecitabine can be considered to be a treatment option in HER2-positive advanced breast cancer patients who have shown primary resistance to trastuzumab. Even in the era of modern anti-HER2 treatments, this clinical setting warrants more investigations to meet unmet needs. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04001621. Retrospectively registered on June 28, 2019.

Low level of ARID1A contributes to adaptive immune resistance and sensitizes triple-negative breast cancer to immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) shed new light on triple-negative breast cancer (TNBC), but only a minority of patients demonstrate response. Therefore, adaptive immune resistance (AIR) needs to be further defined to guide the development of ICI regimens. METHODS: Databases, including The Cancer Genome Atlas, Gene Ontology Resource, University of California Santa Cruz Genome Browser, and Pubmed, were used to screen epigenetic modulators, regulators for CD8+ T cells, and transcriptional regulators of programmed cell death-ligand 1 (PD-L1). Human peripheral blood mononuclear cell (Hu-PBMC) reconstruction mice were adopted for xenograft transplantation. Tumor specimens from a TNBC cohort and the clinical trial CTR20191353 were retrospectively analyzed. RNA-sequencing, Western blotting, qPCR and immunohistochemistry were used to assess gene expression. Coculture assays were performed to evaluate the regulation of TNBC cells on T cells. Chromatin immunoprecipitation and transposase-accessible chromatin sequencing were used to determine chromatin-binding and accessibility. RESULTS: The epigenetic modulator AT-rich interaction domain 1A (ARID1A) gene demonstrated the highest expression association with AIR relative to other epigenetic modulators in TNBC patients. Low ARID1A expression in TNBC, causing an immunosuppressive microenvironment, promoted AIR and inhibited CD8+ T cell infiltration and activity through upregulating PD-L1. However, ARID1A did not directly regulate PD-L1 expression. We found that ARID1A directly bound the promoter of nucleophosmin 1 (NPM1) and that low ARID1A expression increased NPM1 chromatin accessibility as well as gene expression, further activating PD-L1 transcription. In Hu-PBMC mice, atezolizumab demonstrated the potential to reverse ARID1A deficiency-induced AIR in TNBC by reducing tumor malignancy and activating anti-tumor immunity. In CTR20191353, ARID1A-low patients derived more benefit from pucotenlimab compared to ARID1A-high patients. CONCLUSIONS: In AIR epigenetics, low ARID1A expression in TNBC contributed to AIR via the ARID1A/NPM1/PD-L1 axis, leading to poor outcome but sensitivity to ICI treatment.

Preclinical and clinical activity of DZD1516, a full blood-brain barrier-penetrant, highly selective HER2 inhibitor.

BACKGROUND: Patients with HER2-positive metastatic breast cancer (MBC) are at high risk of developing central nervous system (CNS) metastases. A potent and selective HER2 inhibitor with good blood-brain barrier (BBB) penetration is highly desirable. METHODS: The design and structure-activity relationship of DZD1516 was described. The potency and selectivity of DZD1516 were determined by enzymatic and cellular assays. The antitumor activity of DZD1516 monotherapy or in combination with HER2 antibody-drug conjugate was assessed in CNS and subcutaneous xenograft mouse models. A phase 1 first-in-human study evaluated the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of DZD1516 in patients with HER2+ MBC who relapsed from standard of care. RESULTS: DZD1516 showed good selectivity against HER2 over wild-type EGFR in vitro and potent antitumor activity in vivo. Twenty-three patients were enrolled and received DZD1516 monotherapy treatment across six dose levels (25-300 mg, twice daily). Dose-limiting toxicities were reported at 300 mg, and thus 250 mg was defined as the maximum tolerated dose. The most common adverse events included headache, vomiting, and hemoglobin decreased. No diarrhea or skin rash was observed at ≤ 250 mg. The mean Kp,uu,CSF was 2.1 for DZD1516 and 0.76 for its active metabolite DZ2678. With median seven lines of prior systemic therapy, the best antitumor efficacy in intracranial, extracranial and overall lesions was stable disease. CONCLUSIONS: DZD1516 provides positive proof of concept for an optimal HER2 inhibitor with high BBB penetration and HER2 selectivity. Further clinical evaluation of DZD1516 is warranted, with the RP2D being 250 mg BID. CLINICALTRIALS: gov identifier NCT04509596. Registered on August 12, 2020; Chinadrugtrial: CTR20202424 Registered on December 18, 2020.

A study of clinical and molecular characteristics in bilateral primary breast cancer.

BACKGROUND: Bilateral primary breast cancer (BPBC) is a rare type of breast cancer. Studies on the clinicopathologic and molecular characteristics of BPBC in a metastatic context are very limited. METHODS: A total of 574 unselected metastatic breast cancer patients with clinical information were enrolled in our next-generation sequencing (NGS) database. Patients with BPBC from our NGS database were regarded as the study cohort. In addition, 1467 patients with BPBC and 2874 patients with unilateral breast cancer (UBC) from the Surveillance, Epidemiology, and End Results (SEER) public database were also analyzed to determine the characteristics of BPBC. RESULTS: Among the 574 patients enrolled in our NGS database, 20 (3.5%) patients had bilateral disease, comprising 15 (75%) patients with synchronous bilateral disease and 5 (25%) patients with metachronous bilateral disease. Eight patients had bilateral hormone receptor-positive (HR+)/human epidermal growth factor receptor-negative (HER2-) tumors, and three had unilateral HR+/HER2- tumors. More HR+/HER2- tumors and lobular components were found in BPBC patients than in UBC patients. The molecular subtype of the metastatic lesions in three patients was inconsistent with either side of the primary lesions, which suggested the importance of rebiopsy. Strong correlations in clinicopathologic features between the left and right tumors in BPBC were exhibited in the SEER database. In our NGS database, only one BPBC patient was found with a pathogenic germline mutation in BRCA2. The top mutated somatic genes in BPBC patients were similar to those in UBC patients, including TP53 (58.8% in BPBC and 60.6% in UBC) and PI3KCA (47.1% in BPBC and 35.9% in UBC). CONCLUSIONS: Our study suggested that BPBC may tend to be lobular carcinoma and have the HR+/HER2- subtype. Although our study did not find specific germline and somatic mutations in BPBC, more research is needed for verification.

Analysis of clinical features, genomic landscapes and survival outcomes in HER2-low breast cancer.

BACKGROUND: Novel human epidermal growth factor receptor 2 (HER2)-directed antibody-drug conjugates prompt the identification of the HER2-low subtype. However, the biological significance of HER2-low expression in breast cancer is unclear. METHODS: Clinical and genomic data of 579 metastatic breast cancer patients were reviewed from our next-generation sequencing (NGS) database and genomic analysis of early breast cancer patients from TCGA was also analyzed. FINDINGS: First, the clinicopathological characteristics of HER2-low patients were profoundly influenced by HR status and no difference of prognosis was observed between HER2-low and HER2-zero patients when paired by HR status, but notably HER2-low patients showed similar metastatic patterns to HER2-positive patients in the HR-positive (HR+ ) subgroup, with more brain and initial lung metastases and more cases of de novo stage IV breast cancer than HER2-zero patients. Second, among patients with primary HER2-low or HER2-zero tumors, the discordance of HER2 status between primary and metastatic tumors was significant, with 48.4% of patients with HER2-zero primary tumors exhibiting HER2-low phenotype in metastatic tumors in the HR+ subgroup. Third, within HR+ and HR-negative subtypes, HER2-low and HER2-zero tumors showed no substantial differences in mutation alterations and copy number variations. Forth, germline BRCA2 mutations were observed only in HER2-low patients in our NGS database, especially in HR+ HER2-low tumors. Finally, three molecular subtypes based on genomic alterations in HER2-low breast cancer were identified, which provided novel insights into heterogeneity in HER2-low breast cancer. CONCLUSIONS: After correcting for HR expression, only marginal differences in clinical and molecular phenotypes were determined between HER2-low and HER2-zero breast cancer. Therefore, HER2-low breast cancer is insufficient to be defined as a distinct molecular entity, but rather a heterogenous disease.

Early changes in soluble intracellular adhesion molecule-1 as prognostic biomarkers to immune checkpoint inhibitor.

Serologic biomarker to predict clinical outcome is needed for immune checkpoint inhibitors (ICIs). We evaluated soluble intercellular adhesion molecules-1 (sICAM-1) as a predictor of response to ICIs treatment. Ninety-five patients with cancer treated with ICI were studied. The serum sICAM-1 levels of baseline, post two cycle therapy and end of therapy (EOT) were measured by enzyme-linked immunoassay. We randomly assigned the patients into the primary cohort (n = 47) and validation cohort (n = 48). Serum sICAM-1 post two cycle (277.7 ± 181.6 ng/mL) and EOT (403.9 ± 218.9 ng/mL) were significantly elevated compared to baseline (244.8 ± 153.8 ng/mL, p = 0.008 and p = 0.004, respectively). Early changes of sICAM-1 (ΔsICAM-1), deemed as sICAM-1 after two cycles minus baseline, were assessed. Following ICI treatments, responders had significantly lower ΔsICAM-1 compared with nonresponders in the primary cohort (p = 0.040) and the validation cohort (p = 0.026). High ΔsICAM-1 was strongly associated with inferior progression-free survival (PFS; (primary cohort: p = 0.001 and validation cohort: p = 0.002) and overall survival (OS; (primary cohort: p < 0.001 and validation cohort: p = 0.007). The ΔsICAM-1 remained independently associated with worse PFS and OS in the primary cohort and the validation cohort. Subgroup analysis indicated patients whose sICAM-1 significantly elevated had shorter PFS and OS in both anti-PD-1 and anti-PD-L1 treatment groups. Early change of serum sICAM-1 could be used to monitor and predict clinical benefit of ICI therapy in patients with solid cancer.

Cuproptosis-related risk score predicts prognosis and characterizes the tumor microenvironment in colon adenocarcinoma.

Introduction: Cuproptosis is a novel copper-dependent regulatory cell death (RCD), which is closely related to the occurrence and development of multiple cancers. However, the potential role of cuproptosis-related genes (CRGs) in the tumor microenvironment (TME) of colon adenocarcinoma (COAD) remains unclear. Methods: Transcriptome, somatic mutation, somatic copy number alteration and the corresponding clinicopathological data of COAD were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database (GEO). Difference, survival and correlation analyses were conducted to evaluate the characteristics of CRGs in COAD patients. Consensus unsupervised clustering analysis of CRGs expression profile was used to classify patients into different cuproptosis molecular and gene subtypes. TME characteristics of different molecular subtypes were investigated by using Gene set variation analysis (GSVA) and single sample gene set enrichment analysis (ssGSEA). Next, CRG Risk scoring system was constructed by applying logistic least absolute shrinkage and selection operator (LASSO) cox regression analysis and multivariate cox analysis. Real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC) were used to exam the expression of key Risk scoring genes. Results: Our study indicated that CRGs had relatively common genetic and transcriptional variations in COAD tissues. We identified three cuproptosis molecular subtypes and three gene subtypes based on CRGs expression profile and prognostic differentially expressed genes (DEGs) expression profile, and found that changes in multilayer CRGs were closely related to the clinical characteristics, overall survival (OS), different signaling pathways, and immune cell infiltration of TME. CRG Risk scoring system was constructed according to the expression of 7 key cuproptosis-related risk genes (GLS, NOX1, HOXC6, TNNT1, GLS, HOXC6 and PLA2G12B). RT-qPCR and IHC indicated that the expression of GLS, NOX1, HOXC6, TNNT1 and PLA2G12B were up-regulated in tumor tissues, compared with those in normal tissues, and all of GLS, HOXC6, NOX1 and PLA2G12B were closely related with patient survival. In addition, high CRG risk scores were significantly associated with high microsatellite instability (MSI-H), tumor mutation burden (TMB), cancer stem cell (CSC) indices, stromal and immune scores in TME, drug susceptibility, as well as patient survival. Finally, a highly accurate nomogram was constructed to promote the clinical application of the CRG Risk scoring system. Discussion: Our comprehensive analysis showed that CRGs were greatly associated with TME, clinicopathological characteristics, and prognosis of patient with COAD. These findings may promote our understanding of CRGs in COAD, providing new insights for physicians to predict prognosis and develop more precise and individualized therapy strategies.

GepLiver: an integrative liver expression atlas spanning developmental stages and liver disease phases.

Chronic liver diseases usually developed through stepwise pathological transitions under the persistent risk factors. The molecular changes during liver transitions are pivotal to improve liver diagnostics and therapeutics yet still remain elusive. Cumulative large-scale liver transcriptomic studies have been revealing molecular landscape of various liver conditions at bulk and single-cell resolution, however, neither single experiment nor databases enabled thorough investigations of transcriptomic dynamics along the progression of liver diseases. Here we establish GepLiver, a longitudinal and multidimensional liver expression atlas integrating expression profiles of 2469 human bulk tissues, 492 mouse samples, 409,775 single cells from 347 human samples and 27 liver cell lines spanning 16 liver phenotypes with uniformed processing and annotating methods. Using GepLiver, we have demonstrated dynamic changes of gene expression, cell abundance and crosstalk harboring meaningful biological associations. GepLiver can be applied to explore the evolving expression patterns and transcriptomic features for genes and cell types respectively among liver phenotypes, assisting the investigation of liver transcriptomic dynamics and informing biomarkers and targets for liver diseases.

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 BRAFV600 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.

Chromatin Remodelling Molecule ARID1A Determines Metastatic Heterogeneity in Triple-Negative Breast Cancer by Competitively Binding to YAP.

Heterogeneity represents a pivotal factor in the therapeutic failure of triple-negative breast cancer (TNBC). In this study, we retrospectively collected and analysed clinical and pathological data from 258 patients diagnosed with TNBC at the Fudan University Cancer Hospital. Our findings show that low ARID1A expression is an independent prognostic indicator for poor overall survival (OS) and recurrence-free survival (RFS) in TNBC patients. Mechanistically, both nuclear and cytoplasmic protein analyses and immunofluorescent localisation assays confirm that ARID1A recruits the Hippo pathway effector YAP into the nucleus in human triple-negative breast cancer cells. Subsequently, we designed a YAP truncator plasmid and confirmed through co-immunoprecipitation that ARID1A can competitively bind to the WW domain of YAP, forming an ARID1A/YAP complex. Moreover, the downregulation of ARID1A promoted migration and invasion in both human triple-negative breast cancer cells and xenograft models through the Hippo/YAP signalling axis. Collectively, these findings demonstrate that ARID1A orchestrates the molecular network of YAP/EMT pathways to affect the heterogeneity in TNBC.

Dalpiciclib plus letrozole or anastrozole versus placebo plus letrozole or anastrozole as first-line treatment in patients with hormone receptor-positive, HER2-negative advanced breast cancer (DAWNA-2): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Adding CDK4/6 inhibitor dalpiciclib to fulvestrant significantly prolonged progression-free survival in patients with hormone receptor-positive, HER2-negative advanced breast cancer progressing after endocrine therapy. We aimed to assess the efficacy and safety of dalpiciclib plus letrozole or anastrozole in patients with hormone receptor-positive, HER2-negative advanced breast cancer who had no previous systemic therapy in the advanced setting. METHODS: DAWNA-2 is a randomised, double-blind, placebo-controlled, phase 3 trial done at 42 hospitals in China. Eligible patients were aged 18-75 years, of any menopausal status, had an ECOG performance status of 0-1, and had pathologically confirmed hormone receptor-positive, HER2-negative untreated advanced breast cancer. Patients were randomly assigned (2:1) to receive oral dalpiciclib (150 mg per day for 3 weeks, followed by 1 week off) or matching placebo. Both groups also received endocrine therapy: either 2·5 mg letrozole or 1 mg anastrozole orally once daily continuously. Randomisation was using an interactive web response system (block size of six) and stratified according to visceral metastasis, previous endocrine therapy in the adjuvant or neoadjuvant setting, and endocrine therapy partner. All investigators, patients, and the funders of the study were masked to group allocation. We present the results of the preplanned interim analyses for the primary endpoint of investigator-assessed progression-free survival, which was assessed in all randomly assigned patients who met the eligibility criteria by intention-to treat. Safety was analysed in all randomly assigned patients who received at least one dose of study treatment. The superiority boundary was calculated as a one-sided p value of 0·0076 or less. This trial is registered with ClinicalTrials.gov, NCT03966898, and is ongoing but closed to recruitment. FINDINGS: Between July 19, 2019, and Dec 25, 2020, 580 patients were screened and 456 were eligible and randomly assigned to the dalpiciclib group (n=303) or placebo group (n=153). At data cutoff (June 1, 2022), median follow-up was 21·6 months (IQR 18·3-25·9), and 103 (34%) of 303 patients in the dalpiciclib group and 83 (54%) of 153 patients in the placebo group had disease progression or died. Median progression-free survival was significantly longer in the dalpiciclib group than in the placebo group (30·6 months [95% CI 30·6-not reached] vs 18·2 months [16·5-22·5]; stratified hazard ratio 0·51 [95% CI 0·38-0·69]; one-sided log-rank p<0·0001). Adverse events of grade 3 or 4 were reported in 271 (90%) of 302 patients in the dalpiciclib group and 18 (12%) of 153 patients in the placebo group. The most common adverse events of grade 3 or 4 were neutropenia (259 [86%] in the dalpiciclib group vs none in the placebo group) and leukopenia (201 [67%] vs none). Serious adverse events were reported for 36 (12%) patients in the dalpiciclib group and ten (7%) patients in the placebo group. Two treatment-related deaths occurred, both in the dalpiciclib group (deaths from unknown causes). INTERPRETATION: Our findings suggest that dalpiciclib plus letrozole or anastrozole could be a novel standard first-line treatment for patients with hormone receptor-positive, HER2-negative advanced breast cancer, and is an alternative option to the current treatment landscape. FUNDING: Jiangsu Hengrui Pharmaceuticals and Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Entinostat, a class I selective histone deacetylase inhibitor, plus exemestane for Chinese patients with hormone receptor-positive advanced breast cancer: A multicenter, randomized, double-blind, placebo-controlled, phase 3 trial.

Entinostat plus exemestane in hormone receptor-positive (HR+) advanced breast cancer (ABC) previously showed encouraging outcomes. This multicenter phase 3 trial evaluated the efficacy and safety of entinostat plus exemestane in Chinese patients with HR + ABC that relapsed/progressed after ≥1 endocrine therapy. Patients were randomized (2:1) to oral exemestane 25 mg/day plus entinostat (n = 235) or placebo (n = 119) 5 mg/week in 28-day cycles. The primary endpoint was the independent radiographic committee (IRC)-assessed progression-free survival (PFS). The median age was 52 (range, 28-75) years and 222 (62.7%) patients were postmenopausal. CDK4/6 inhibitors and fulvestrant were previously used in 23 (6.5%) and 92 (26.0%) patients, respectively. The baseline characteristics were comparable between the entinostat and placebo groups. The median PFS was 6.32 (95% CI, 5.30-9.11) and 3.72 (95% CI, 1.91-5.49) months in the entinostat and placebo groups (HR, 0.76; 95% CI, 0.58-0.98; P = 0.046), respectively. Grade ≥3 adverse events (AEs) occurred in 154 (65.5%) patients in the entinostat group versus 23 (19.3%) in the placebo group, and the most common grade ≥3 treatment-related AEs were neutropenia [103 (43.8%)], thrombocytopenia [20 (8.5%)], and leucopenia [15 (6.4%)]. Entinostat plus exemestane significantly improved PFS compared with exemestane, with generally manageable toxicities in HR + ABC (ClinicalTrials.gov #NCT03538171).

Capivasertib in Hormone Receptor-Positive Advanced Breast Cancer.

BACKGROUND: AKT pathway activation is implicated in endocrine-therapy resistance. Data on the efficacy and safety of the AKT inhibitor capivasertib, as an addition to fulvestrant therapy, in patients with hormone receptor-positive advanced breast cancer are limited. METHODS: In a phase 3, randomized, double-blind trial, we enrolled eligible pre-, peri-, and postmenopausal women and men with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer who had had a relapse or disease progression during or after treatment with an aromatase inhibitor, with or without previous cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor therapy. Patients were randomly assigned in a 1:1 ratio to receive capivasertib plus fulvestrant or placebo plus fulvestrant. The dual primary end point was investigator-assessed progression-free survival assessed both in the overall population and among patients with AKT pathway-altered (PIK3CA, AKT1, or PTEN) tumors. Safety was assessed. RESULTS: Overall, 708 patients underwent randomization; 289 patients (40.8%) had AKT pathway alterations, and 489 (69.1%) had received a CDK4/6 inhibitor previously for advanced breast cancer. In the overall population, the median progression-free survival was 7.2 months in the capivasertib-fulvestrant group, as compared with 3.6 months in the placebo-fulvestrant group (hazard ratio for progression or death, 0.60; 95% confidence interval [CI], 0.51 to 0.71; P<0.001). In the AKT pathway-altered population, the median progression-free survival was 7.3 months in the capivasertib-fulvestrant group, as compared with 3.1 months in the placebo-fulvestrant group (hazard ratio, 0.50; 95% CI, 0.38 to 0.65; P<0.001). The most frequent adverse events of grade 3 or higher in patients receiving capivasertib-fulvestrant were rash (in 12.1% of patients, vs. in 0.3% of those receiving placebo-fulvestrant) and diarrhea (in 9.3% vs. 0.3%). Adverse events leading to discontinuation were reported in 13.0% of the patients receiving capivasertib and in 2.3% of those receiving placebo. CONCLUSIONS: Capivasertib-fulvestrant therapy resulted in significantly longer progression-free survival than treatment with fulvestrant alone among patients with hormone receptor-positive advanced breast cancer whose disease had progressed during or after previous aromatase inhibitor therapy with or without a CDK4/6 inhibitor. (Funded by AstraZeneca and the National Cancer Institute; CAPItello-291 ClinicalTrials.gov number, NCT04305496.).

Phase I study of A166, an antibody‒drug conjugate in advanced HER2-expressing solid tumours.

In this phase I study, the safety, pharmacokinetics, and antitumour activity of the HER2-targeted antibody-drug conjugate A166 were evaluated in patients with HER2-expressing advanced solid tumours. Patients with advanced solid tumours refractory to standard therapies received A166 at doses of 0.1, 0.3, 0.6, 1.2, 2.4, 3.6, 4.8 or 6.0 mg/kg Q3W in a standard "3 + 3" design. Dose cohorts were expanded at 4.8 and 6.0 mg/kg Q3W. Primary endpoints were assessment of the safety and tolerability of A166 and identification of the maximum tolerated dose or recommended phase II dose. In total, 81 patients were enroled and received A166 (n = 1 for 0.1 mg/kg; n = 3 for each of 0.3, 0.6, 1.2, 2.4 and 3.6 mg/kg doses; n = 27 for 4.8 mg/kg; n = 38 for 6.0 mg/kg). No dose-limiting toxicity or drug-related deaths occurred. The most common treatment-related adverse events at grade 3 or higher were corneal epitheliopathy (30.9%), blurred vision (18.5%), dry eyes (7.4%), and peripheral sensory neuropathy (6.2%). The Cmax and area under the curve of Duo-5, its free payload, were approximately 0.1% and 0.2% of those of the ADC, respectively. For all assessable HER2-positive breast cancer patients enroled in the 4.8 mg/kg and 6.0 mg/kg cohorts, the corresponding ORRs were 73.9% (17/23) and 68.6% (24/35), respectively, and the median PFS was 12.3 and 9.4 months, respectively. A166 has a recommended phase II dose of 4.8 mg/kg Q3W, manageable toxicity, good stability in the circulation and promising antitumour activities in HER2-positive breast cancer patients.

Phase I study of MSB2311, a novel pH-dependent anti-PD-L1 monoclonal antibody, treating patients with advanced solid tumors and lymphoma.

MSB2311 is a novel pH-dependent humanized anti-programmed death-ligand 1 (PD-L1) monoclonal antibody. This phase I study primarily aimed to determine the maximum tolerated dose (MTD)/recommended phase 2 dose level (RP2D) of MSB2311 in patients with advanced solid tumors or lymphoma. MSB2311 was intravenously administered at 3, 10, and 20 mg/kg every 3 weeks (Q3W) and 10 mg/kg every 2 weeks (Q2W) using 3 + 3 design. During expansion phase, eligible patients with either PD-L1 overexpression, Epstein-Barr Virus positive, microsatellite instability high/mismatch repair deficient, or high tumor mutation burden tumors were treated at RP2D. A total of 37 Chinese patients were treated, including 31 with solid tumors and 6 lymphoma. No dose limiting toxicity was reported and MTD was not reached. The trial was expanded at 20 mg/kg Q3W or 10 mg/kg Q2W, both of which were determined as RP2D. Most common drug-related treatment-emergent adverse events were anemia (43.2%), aspartate aminotransferase increase (27.0%), proteinuria (21.6%), alanine aminotransferase increase and hypothyroidism (18.9% each), thyroid stimulating hormone increased and hyperglycemia (16.2% each). Out of 20 efficacy evaluable patients with biomarker positive solid tumors, 6 achieved confirmed partial response with the median duration of response of 11.0 months (95% CI 7.0-11.4) and 4 had stable disease, resulting an objective response rate of 30.0% (95% CI 11.9, 54.3) and disease control rate of 50.0% (95% CI 27.2, 72.8). One partial response was also observed among 6 patients with lymphoma. MSB2311 demonstrated a manageable safety profile and promising antitumor activity in patients with advanced solid tumors and lymphomas.

UBE2S and UBE2C confer a poor prognosis to breast cancer via downregulation of Numb.

Purpose: Ubiquitin-conjugating enzymes E2S (UBE2S) and E2C (UBE2C), which mediate the biological process of ubiquitination, have been widely reported in various cancers. Numb, the cell fate determinant and tumor suppressor, was also involved in ubiquitination and proteasomal degradation. However, the interaction between UBE2S/UBE2C and Numb and their roles in the clinical outcome of breast cancer (BC) are not widely elucidated. Methods: Oncomine, Cancer Cell Line Encyclopedia (CCLE), the Human Protein Atlas (HPA) database, qRT-PCR, and Western blot analyses were utilized to analyze UBE2S/UBE2C and Numb expression in various cancer types and their respective normal controls, breast cancer tissues, and breast cancer cell lines. The expression of UBE2S, UBE2C, and Numb in BC patients with different ER, PR, and HER2 status, grades, stages, and survival status was compared. By Kaplan-Meier plotter, we further evaluated the prognostic value of UBE2S, UBE2C, and Numb in BC patients. We also explored the potential regulatory mechanisms underlying UBE2S/UBE2C and Numb through overexpression and knockdown experiments in BC cell lines and performed growth and colony formation assays to assess cell malignancy. Results: In this study, we showed that UBE2S and UBE2C were overexpressed while Numb was downregulated in BC, and in BC of higher grade, stage, and poor survival. Compared to hormone receptor negative (HR-) BC cell lines or tissues, HR+ BC demonstrated lower UBE2S/UBE2C and higher Numb, corresponding to better survival. We also showed that increased UBE2S/UBE2C and reduced Numb predicted poor prognosis in BC patients, as well as in ER+ BC patients. In BC cell lines, UBE2S/UBE2C overexpression decreased the level of Numb and enhanced cell malignancy, while knocking down UBE2S/UBE2C demonstrated the opposite effects. Conclusion: UBE2S and UBE2C downregulated Numb and enhanced BC malignancy. The combination of UBE2S/UBE2C and Numb could potentially serve as novel biomarkers for BC.