Breast Cancer Research最新文献

Background: Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate that is an effective therapy for HER2-positive breast cancer; however, its efficacy is limited by drug resistance. While multiple mechanisms of resistance have been proposed, these are not yet well understood. Greater understanding of T-DM1 sensitivity and resistance could provide new combination strategies to overcome resistance or predictive biomarkers to guide therapy.

Methods: We have conducted CRISPR/Cas9 functional genomics modifier screens in HER2-positive breast cancer cell lines to allow for unbiased discovery of T-DM1 sensitivity and resistance genes. Whole-genome knockout screens were carried out in MDA-MB-361 and MDA-MB-453 cells treated with T-DM1 and its payload cytotoxin DM1. Hits were validated in secondary T-DM1 screens using a focused single-guide RNA (sgRNA) library and subsequently by individual gene knockout.

Results: The whole-genome CRISPR screens with T-DM1 and DM1 identified 599 genes as potential modifiers of T-DM1 sensitivity and resistance. Of these, 17 genes were significantly enriched and 3 genes depleted at P < 0.001 in either or both MDA-MB-361 and MDA-MB-453 libraries in the secondary screens. Among the top hits, were known T-DM1 sensitivity genes ERBB2 and SLC46A3, in addition to negative regulators of mTOR complex 1: TSC1 and TSC2. MDA-MB-453 clones with knockout of TSC1 or partial knockout of TSC2 were more resistant to T-DM1 than wild type cells in competition growth assays and to T-DM1 and other HER2 targeting therapies (T-DXd, lapatinib and neratinib) in growth inhibition assays, and had increased internalisation of T-DM1 at 6 h. T-DM1 and the mTOR inhibitor everolimus demonstrated synergistic activity at inhibiting cell proliferation at multiple T-DM1 concentrations across four HER2-positive breast cancer cell lines.

Conclusions: Our CRISPR screening approach with T-DM1 in HER2-positive breast cancer cell lines identified genes not previously implicated in T-DM1 sensitivity or resistance, including TSC1 and TSC2. These genes may inform new strategies to enhance T-DM1 therapy in the clinic.

Breast cancer is the most prevalent cancer in women worldwide. Aberrant epigenetic reprogramming such as dysregulation of histone acetylation has been associated with the development of breast cancer. Histone acetylation modulators have been targeted as potential treatments for breast cancer. This review comprehensively discusses the roles of these modulators and the effects of their inhibitors on breast cancer. In addition, epigenetic reprogramming not only affects breast cancer cells but also the immunosuppressive myeloid cells, which can facilitate breast cancer progression. Therefore, the review also highlights the roles of these immunosuppressive myeloid cells and summarizes how histone acetylation modulators affect their functions and phenotypes. This review provides insights into histone acetylation modulators as potential therapeutic targets for breast cancer.

Background: Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype characterized with poor prognosis and high metastatic potential. Although traditional chemotherapy, radiation, and surgical resection remain the standard treatment options for TNBC, bispecific antibody-based immunotherapy is emerging as new strategy in TNBC treatment. Here, we found that the receptor tyrosine kinase-like Orphan Receptor 1 (ROR1) was highly expressed in TNBC but minimally expressed in normal tissue. A bispecific ROR1-targeted CD3 T cell engager (TCE) was designed in IgG-based format with extended half-life.

Method: The expression of ROR1 in TNBC was detected by RT-qPCR and immunohistology analysis. The killing of ROR1/CD3 antibody on TNBC cells was determined by the in vitro cytotoxicity assay and in vivo PBMC reconstituted mouse model. The activation of ROR1/CD3 on T cells was analyzed by the flow cytometry and ELISA assay. Pharmacokinetics study of ROR1/CD3 was performed in mouse.

Results: The ROR1/CD3 TCE triggered T cell activation and proliferation, which showed potent and specific killing to TNBC cells in ROR1-depedent manner. In vivo mouse model indicated that ROR1/CD3 TCE redirected the cytotoxic activity of T cells to lyse TNBC cells and induced significant tumor regression. Additionally, the ROR1/CD3 bispecific antibody exhibited an extended half-life in mouse, which may enable intermittent administration in clinic.

Conclusions: Collectively, these results demonstrated that ROR1/CD3 TCE has a promising efficacy profile in preclinical studies, which suggested it as a possible option for the treatment of ROR1-expressing TNBC.

Background: In HR+/HER2- early breast cancer (EBC) patients, approximately one-third of stage II and 50% of stage III patients experience recurrence, with poor outcomes after recurrence. Given that these patients commonly undergo adjuvant chemo-endocrine therapy (C-ET), accurately predicting the recurrence risk is crucial for optimizing treatment strategies and improving patient outcomes.

Methods: We collected postoperative histopathological slides from 1095 HR+/HER2- EBC who received C-ET and were followed for more than five years at West China Hospital, Sichuan University. Two deep learning pipelines were developed and validated: ACMIL-based and CLAM-based. Both pipelines, designed to predict recurrence risk post-treatment, were based on pretrained feature encoders and multi-instance learning with attention mechanisms. Model performance was evaluated using a five-fold cross-validation approach and externally validated on HR+/HER2- EBC patients from the TCGA cohort.

Results: Both ACMIL-based and CLAM-based pipelines performed well in predicting recurrence risk, with UNI-ACMIL demonstrating superior performance across multiple metrics. The average area under the curve (AUC) for the UNI-ACMIL pipeline in the five-fold cross-validation test set was 0.86 ± 0.02, and 0.80 ± 0.04 in the TCGA cohort. In the five-fold cross-validation test sets, effectively stratified patients into high-risk and low-risk groups, demonstrating significant prognostic differences. Hazard ratios for recurrence-free survival (RFS) ranged from 5.32 (95% CI 1.86-15.12) to 15.16 (95% CI 3.61-63.56). Moreover, among six different multimodal recurrence risk models, the WSI-based risk score was identified as the most significant contributor.

Conclusion: Our multimodal recurrence risk prediction model is a practical and reliable tool that enhances the predictive power of existing systems relying solely on clinicopathological parameters. It offers improved recurrence risk prediction for HR+/HER2- EBC patients following adjuvant C-ET, supporting personalized treatment and better patient outcomes.

Background: Blood DNA methylation (DNAm) profiles have been used to show that changes in circulating leukocyte composition occur during breast cancer development, suggesting that peripheral immune system alterations are markers of breast cancer risk. Blood DNAm profiles have recently been used to predict plasma protein concentrations ("Protein EpiScores"), but their associations with breast cancer risk have not been examined in detail.

Methods: Whole blood DNAm profiles were obtained for a case-cohort sample of participants in the Sister Study and used to calculate 109 Protein EpiScores. Of the 4,479 women included, 2,151 (48%) were diagnosed with breast cancer within 15 years of their baseline blood draw (median time to diagnosis: 8.6 years; 1,673 invasive cancer and 478 ductal carcinomas in situ). Protein EpiScores associations with breast cancer incidence were estimated using weighted Cox regression models, overall and stratified by time and participant characteristics.

Results: Protein EpiScores for RARRES2, IGFBP4, and CCL21 were positively associated with invasive breast cancer risk (hazard ratios from 1.17 to 1.24), while those for F7, SELL, CXCL9, CD48, and IL19 were inversely associated (hazard ratios from 0.82 to 0.86) (all FDR < 0.10). Eight immune response-related Protein EpiScores (CXCL9, CD48, FCGR3B, CXCL11, CCL21, CRTAM, VCAM1, GZMA) were associated with invasive cancers diagnosed within five years of enrollment. Protein EpiScore associations were consistently stronger for estrogen receptor-negative tumors.

Conclusions: Several Protein EpiScores, including many related to immune response, were associated with breast cancer risk, highlighting novel changes to the peripheral immune system that occur during breast cancer development.

Background: Accurately assessing HER2-low (immunohistochemistry [IHC] 1 + and IHC 2+/in situ hybridization [ISH]-) and HER2-ultralow (IHC > 0 < 1+) is essential given the emergence of novel therapies. Thorough understanding of the reproducibility of rescoring IHC stained slides or re-staining archived tissue slides is essential.

Methods: 2,869 breast cancer patients diagnosed between July 2021 and July 2022 from 10 hospitals in China were included in this multicentre study. The prevalence of different HER2 expression levels and distribution of HER2 IHC scores were assessed by HER2 status determination from rescored historical slides. Concordance was evaluated across historical results versus rescored results, historical results versus re-stained results, and leading center results versus local site results. Clinicopathological characteristics were retrospectively analyzed as well.

Results: HER2 IHC 0, IHC 1+, IHC 2+, and IHC 3 + were identified in 682 (23.8%), 871 (30.4%), 801 (27.9%), and 515 (18.0%) cases, respectively. HER2-positive, HER2-low, and HER2 IHC 0 (HER2-ultralow and IHC null) were identified in 21.7%, 54.5%, and 23.8% of cases, respectively. The prevalence of HER2-ultralow and IHC null was 10.6% and 13.2%, respectively. The concordance for HER2-ultralow was 43.3%; 30% of cases that were scored as HER2-ultralow at local sites were rescored as HER2-null and 26.7% of cases were rescored as IHC 1 + at the leading site. Overall, there was substantial agreement (83.1%) between rescored and historical IHC results. A high concordance rate of 91.7% was observed for HER2-low classification.

Conclusions: This is the first multicenter study to determine the prevalence of HER2-low and HER2-ultralow based on rescored results in the Chinese breast cancer population. The concordance analysis carries important implications for the diagnosis of HER2-low and HER2-ultralow cases in clinical practice. The relatively low concordance in identifying HER2-ultralow suggested that the reproducibility of scoring HER2-ultralow needed to be improved through training.

Trial registration: ClinicalTrials.gov identifier NCT05203458.

Background: Progression from pre-cancers like ductal carcinoma in situ (DCIS) to invasive disease (cancer) is driven by somatic evolution and is altered by clinical interventions. We hypothesized that genetic and/or phenotypic intra-tumor heterogeneity would predict clinical outcomes for DCIS since it serves as the substrate for natural selection among cells.

Methods: We profiled two samples from two geographically distinct foci from each DCIS in both cross-sectional (n = 119) and longitudinal cohorts (n = 224), with whole exome sequencing, low-pass whole genome sequencing, and a panel of immunohistochemical markers.

Results: In the longitudinal cohorts, the only statistically significant associations with time to non-invasive DCIS recurrence were the combination of treatment (lumpectomy only vs mastectomy or lumpectomy with radiation, HR 12.13, p = 0.003, Wald test with FDR correction), ER status (HR 0.16 for ER+ compared to ER-, p = 0.0045), and divergence in SNVs between the two samples (HR 1.33 per 10% divergence, p = 0.018). SNV divergence also distinguished between pure DCIS and DCIS synchronous with invasive disease in the cross-sectional cohort. In contrast, the only statistically significant associations with time to progression to invasive disease were the combination of the width of the surgical margin (HR 0.67 per mm, p = 0.043) and the number of mutations that were detectable at high allele frequencies (HR 1.30 per 10 SNVs, p = 0.02). No predictors were significantly associated with both DCIS recurrence and progression to invasive disease, suggesting that the evolutionary scenarios that lead to these clinical outcomes are markedly different.

Conclusions: These results imply that recurrence with DCIS is a clinical and biological process different from invasive progression.

During breast tumor progression, the transition from ductal carcinoma in situ (DCIS) to invasive breast cancer is a critical step with large implications for prognosis. However, the mechanisms of invasion are still largely unknown. At the DCIS stage, there is an over-representation of HER2-positive lesions compared with invasive breast cancer. In this study, we investigated the associations between gene expression profiles in cancer cells and the immune microenvironment of HER2-positive DCIS and invasive breast tumors with concurrent DCIS using spatial transcriptomics. We found distinctly more B cells in the vicinity of DCIS ducts than in invasive tumor areas. There was higher expression of genes involved in energy metabolism in DCIS cancer cells than in invasive cancer cells and a positive correlation between expression of metabolic genes and B-cell abundance in DCIS. In contrast were processes related to epithelial to mesenchymal transition negatively correlated with B-cell abundance in DCIS. We also found significant correlation between expression of the B-cell-attracting chemokines CCL19, CCL21 and CXCL13 in stromal cells and B cell abundance in DCIS. This study indicates that B cells may play a protective role in the progression of HER2-positive DCIS to invasive breast cancer and that increased metabolic activity in intraductal cancer cells in combination with chemokines produced by stromal cells may influence the immune microenvironment of DCIS. These findings have implications for understanding HER2-positive breast cancer progression.

Background: The aim of the present study was to investigate whether the androgen receptor (AR) status affects the efficacy of neoadjuvant chemotherapy (NACT) in triple negative breast cancer (TNBC) patients, and to elucidate the predictive biomarkers and mutations associated with pathological complete response (pCR) in AR-positive TNBC patients.

Methods: The current retrospective cohort included 226 TNBC patients who underwent NACT. AR and FOXC1 were assessed by immunohistochemistry on pretreatment biopsy specimens of 226 TNBC patients from 2018 to 2022. The clinicopathological features of AR-negative, AR < 10%, and AR ≥ 10% TNBC patients were analyzed to confirm the appropriate threshold. The response was evaluated in terms of pCR and Miller-Payne (MP) grade in the subsequent mastectomy or breast conservation samples. Next-generation sequencing (NGS) was utilized to further investigate the molecular characteristics of 44 AR-positive TNBC patients.

Results: Among the 226 TNBC patients, compared with AR-negative and AR < 10% tumors (68.58%, 155/226), AR ≥ 10% TNBC patients (31.41%, 71/226) exhibited distinct clinicopathological features, while no significant difference was detected between those with AR-negative tumors and those with AR < 10% tumors. Thus, tumors with AR ≥ 10% expression were defined as having AR positive expression. The pCR rate of AR-positive TNBCs was lower than that of AR-negative TNBC patients (12.68% vs. 34.19%, p < 0.001). In TNBC, multivariate analysis demonstrated that FOXC1 was an independent predictor of pCR (p = 0.042), whereas AR was not. The pCR rate was higher in FOXC1 positive patients than in FOXC1 negative patients (34.44% vs. 3.13%, p < 0.001). In the AR-positive TNBC subgroup, patients with FOXC1 expression had lower AR expression, higher Ki-67 expression, and higher histological grade. Compared with AR-positive TNBC patients who achieved pCR, the non-pCR patients had a greater percentage of mutations in genes involved in the PI3K/AKT/mTOR pathway.

Conclusions: The current study indicated that the AR-positive TNBC is correlated with lower rates of pCR after NACT. The expression of FOXC1 in TNBC patients and AR-positive TNBC patients could be utilized as a predictive marker for the efficacy of NACT. The present study provides a rationale for treating these non-pCR AR-positive TNBC tumors with PI3K/AKT/mTOR inhibitors.

Background: Recent trials have integrated immune checkpoint inhibitors (ICIs) into neoadjuvant chemotherapy (NAC) in patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer of histologic grade (HG) III. We assessed the pathological complete response (pCR) rate according to the level of stromal tumor-infiltrating lymphocytes (sTIL) and HG in patients with ER + HER2- breast cancer undergoing NAC.

Methods: Between January 2016 and December 2023, we retrospectively identified 376 patients with ER + HER2- breast cancer who underwent NAC followed by surgery. HG and sTIL levels were examined in the biopsied samples before NAC. Multiple sTIL cutoff values as 10%, 20%, and 30% were applied.

Results: Twenty-seven patients (7.2%) had HG III tumors. The pCR rate in the HG III group was 22.2%, which was significantly higher than that in the HG I/II group (4.0%) (p < 0.001). The HG III group had a higher mean sTIL level than HG I/II group (38.7% vs. 12.9%; p < 0.001). According to the sTIL levels, the pCR rate in the high sTIL group was significantly higher than that in the low sTIL group: i) cutoff of 10%, 2.4% vs. 9.5%; cutoff of 20%, 2.8% vs. 13.7%; and cutoff of 30%, 3.2% vs. 18.3%. In the high sTIL (≥ 30%) group, the pCR rate for HG III was 33.3%, whereas that for HG I/II was 13.3%.

Conclusions: High tumor grade and sTIL levels were associated with higher rates of pCR in ER + HER2- breast cancer. Our findings support that the addition to ICIs to NAC increased pCR in high-risk, HG III, ER + HER2- breast cancer and suggest that sTIL levels could be utilized to identify patients with ER + HER2- breast cancer eligible for chemoimmunotherapy.