Dose-dense sequential adjuvant chemotherapy followed, as indicated, by trastuzumab for one year in patients with early breast cancer: first report at 5-year median follow-up of a Hellenic Cooperative Oncology Group randomized phase III trial

A Real-World Comparison Between Adjuvant Docetaxel with Cyclophosphamide (TC) and Anthracycline-Taxane Chemotherapy in Early HER-2 Negative Breast Cancer

BACKGROUND

Anthracycline-taxane chemotherapy is the gold standard in high-risk breast cancer (BC), despite the potential risk of congestive heart failure (CHF). A suitable alternative for anthracycline-sparing chemotherapy is through the combination of docetaxel and cyclophosphamide (TC).

METHODS

Through a retrospective study of stage I-III HER2-negative BC, using administrative databases, we analyzed a total of 10,634 women treated with adjuvant chemotherapy in Ontario, Canada, between 2009 and 2017. We compared TC versus standardized anthracycline-taxane chemotherapies (ACT and FEC-D). We investigated the overall survival (OS), and explored the incidence of CHF, emergency department (ED) visits and febrile neutropenia.

RESULTS

With a median follow-up of 5.5 years, the 5-year analysis showed an increased OS in patients treated with TC, versus those treated with ACT, HR 0.77 (0.63-0.95, p = 0.015). Among ER+ BC, there was an increased OS in patients treated with ACT and FEC-D, versus those treated with TC, HR 0.70 (0.52-0.95, p = 0.021) and HR 0.71 (0.56-0.91, p = 0.007), respectively. There were no substantial differences in CHF, between TC and anthracycline-based treatments. Patients treated with TC and FEC-D had more ED visits, compared to those treated with ACT.

CONCLUSION

Our study shows that anthracycline-taxane regimens were the most commonly prescribed adjuvant chemotherapy options in HER2-negative BC. Women who received ACT had the lowest OS, likely due to their unfavorable pathology.

The Omission of Anthracycline Chemotherapy in Women with Early HER2-Negative Breast Cancer-A Systematic Review and Meta-Analysis

BACKGROUND

Anthracycline-taxane is the standard chemotherapy strategy for treating high-risk early breast cancer despite the potentially life-threatening adverse events caused by anthracyclines. Commonly, the combination of docetaxel and cyclophosphamide (TC) is considered an alternative option. However, the efficacy of TC compared to anthracycline-taxane chemotherapy is unclear. This study compares disease-free survival (DFS), overall survival (OS) and cardiotoxicity between adjuvant TC and anthracycline-taxane for stages I-III, HER2-negative breast cancer.

METHODS

A systematic search on MEDLINE, Embase and Cochrane CENTRAL for randomized-controlled trials published until 11 March 2024, yielded 203 studies with 11,803 patients, and seven trials were included.

RESULTS

TC results in little to no difference in DFS (HR 1.09, 95% CI 0.98-1.20; moderate-certainty of evidence); OS (1.02, 95% CI 0.89-1.16; high-certainty of evidence); and cardiotoxicity (RR 0.54, 95% CI 0.16-1.76; high-certainty of evidence), compared to anthracycline-taxane. In the subgroup analysis, patients with ≥4 lymph nodes had improved DFS from anthracycline-taxane over TC.

CONCLUSIONS

Overall, there was no difference between TC and anthracycline-taxane in DFS, OS and cardiotoxicity. In women with ≥4 nodes, anthracycline-taxane was associated with a substantial reduction in relapse events, compared to TC. Our study supports the current standard of practice, which is to use anthracycline-taxane and TC chemotherapy as a reasonable option in select cases.

Racial and Ethnic Disparities in European Breast Cancer Clinical Trials

Breast cancer is the most prevalent female cancer worldwide with known correlations between the race and tumor characteristics of the patients and prognosis. International and US-based studies, however, have reported a disproportionate representation of Black and Hispanic patients in clinical trials. This is the first study assessing race and ethnicity reporting trends and inclusion in European breast cancer trials. The PubMed and ClinicalTrials.gov databases were systematically searched for trials on breast cancer treatment conducted exclusively in Europe between 2010 and 2022. Of the 97 identified trials, race was reported in 10.31%. Multinational participation, but not the study size or trial phase, was significantly associated with higher race reporting trends. These 10 trials featured a White-predominant population, with 1.08% Asian and 0.88% Black patients included. The acquisition of the race and ethnicity data of patients in European trials is lower compared to the U.S. or worldwide studies and does not permit extensive analysis of minority participation. In a limited analysis, the low rates of minority participation are concerning, based on population-based data on minorities in select European countries. These observations should encourage race reporting practices in European breast cancer trials and adequate minority participation to support the generalizability of the results of the studies and promote healthcare equity.

Ten-year clinical outcome, toxicity and compliance of dose-dense sequential adjuvant administration of cyclophosphamide & epirubicin followed by docetaxel in patients with early breast cancer: A hellenic cooperative oncology group observational study (HE 10/10) with concurrent investigation of significance of tumor infiltrating lymphocytes

BACKGROUND

Dose-dense sequential (dds) chemotherapy has changed the clinical outcome of patients with early breast cancer (BC). To investigate the impact of dose intensity (DI) in the adjuvant setting of BC, this observational trial (HE 10/10) was conducted assessing the long-term survival outcome, safety and toxicity of a currently widely used chemotherapeutic regimen. In addition, the prognostic significance of tumor infiltrating lymphocytes (TILs) and infiltrating CD8+ lymphocytes were also evaluated in the same cohort.

PATIENTS AND METHODS

Totally, 1054 patients were prospectively enrolled in the current study with 1024 patients being eligible, while adequate tissue was available for 596 of them. TILs, CD8+ lymphocytes in intratumoral areas in contact with malignant cells (iCD8), CD8+ lymphocytes in tumor stroma (sCD8) as well as the total number of CD8+ lymphocytes within the tumor area (total CD8) were assessed by immunohistochemistry.

RESULTS

Within a median follow-up of 125.18 months, a total of 200 disease-free survival (DFS) events (19.5%) were reported. Importantly, the 10-year DFS and OS rates were 78.4% (95% CI 75.0-81.5) and 81.7% (95% CI 79.0-84.1), respectively. Interestingly, higher CD8+ T cells as well as TILs in the tumor microenvironment were associated with an improved long-term survival outcome.

CONCLUSIONS

In conclusion, this study confirms the significance of dds adjuvant chemotherapeutic regimen in terms of long-term survival outcome, safety and toxicity as well as the prognostic significance of TILs and infiltrating CD8+ lymphocytes in BC patients with early-stage disease.

Association between CD8+ Tumor Infiltrating Lymphocytes and the Clinical Outcome of Patients with Operable Breast Cancer Treated with Adjuvant Dose-Dense Chemotherapy-A 10 Year Follow-Up Report of a Hellenic Cooperative Oncology Group Observational Study

Tumor-infiltrating lymphocytes (TILs) contribute to breast cancer (BC) prognosis. We investigated the prognostic impact of CD8+ TILs in patients with early breast cancer treated with adjuvant chemotherapy in a large observational clinical trial. Along with a 10 year follow-up, considering the efficacy and safety, we report the results of the translational part of our study. We examined the patients' tumors for total (t), stromal (s), and intratumoral (i) CD8 lymphocyte density (counts/mm²) on tissue-microarray cores. The impact of CD8+ TILs counts on DFS and OS, and its correlation with breast cancer subtypes and standard clinicopathological parameters, were investigated, along with efficacy and safety data. Among the 928 eligible patients, 627 had available CD8+ data. Of which, 24.9% had a high expression of sCD8, iCD8, and total CD8, which were correlated with higher Ki67, TILs density, ER/PgR negativity, and higher histological grade. The 5year DFS and OS rates were 86.1% and 91.4%, respectively. Patients with high iCD8 and tCD8 had longer DFS and OS compared to those with low counts/mm² (DFS: HR = 0.58, p = 0.011 and HR = 0.65, p = 0.034 and OS: HR = 0.63, p = 0.043 and HR = 0.58, p = 0.020, respectively). Upon adjustment for clinicopathological parameters, iCD8 and tCD8 retained their favorable prognostic significance for DFS and OS, whereas high sCD8 was only prognostic for DFS. Menopausal status, tumor size, and nodal status retained their prognostic significance in all examined multivariate models. CD8+ TILs, and especially their intratumoral subset, represent a potential favorable prognostic factor in early BC.

Dose-dense sequential adjuvant chemotherapy in the trastuzumab era: final long-term results of the Hellenic Cooperative Oncology Group Phase III HE10/05 Trial

BACKGROUND

Dose-dense sequential chemotherapy with anthracyclines and taxanes achieved an 18% reduction of recurrence risk in early breast cancer (BC). The optimal chemotherapy schedule and interval between cycles remain under investigation.

METHODS

Overall, 990 patients were randomised to receive either three cycles of epirubicin (E, 110 mg/m²) every 2 weeks followed by 3 cycles of paclitaxel (T, 200 mg/m²) every 2 weeks followed by three cycles of intensified CMF (Control Arm A, E-T-CMF) that was previously used in BC or three cycles of epirubicin followed by three cycles of CMF followed by nine consecutive weekly cycles of docetaxel (wD) 35 mg/m² (Arm B, E-CMF-wD) or nine consecutive weekly cycles of paclitaxel (wT) 80 mg/m² (Arm C, E-CMF-wT). Trastuzumab was administered for HER2-positive disease.

RESULTS

At a median follow-up of 13.3 years, 330 disease-free survival (DFS) events (33.3%) were reported. DFS and overall survival (OS) did not differ between patients in the combined B and C arms versus arm A either in the entire cohort (HR = 0.90, P = 0.38 and HR = 0.85, P = 0.20) or among trastuzumab-treated patients (HR = 0.69, P = 0.13 and HR = 0.67, P = 0.13). Thirty-four patients (3.4%) developed secondary neoplasms.

CONCLUSIONS

Overall, no significant differences in survival were found amongst the studied regimens after a long-term observational period.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12610000151033.

Alpha-smooth Muscle Actin Expression in the Stroma Predicts Resistance to Trastuzumab in Patients with Early-stage HER2-positive Breast Cancer

PURPOSE

The companion diagnostic test for trastuzumab has not changed much in the last 25 years. We used high-plex digital spatial profiling to identify biomarkers besides HER2 that can help predict response to trastuzumab in HER2-positive breast cancer.

EXPERIMENTAL DESIGN

Fifty-eight protein targets were measured in three different molecularly defined compartments by the NanoString GeoMx Digital Spatial Profiler (DSP) in a tissue microarray containing 151 patients with breast cancer that received adjuvant trastuzumab as part of the Hellenic Cooperative Oncology Group 10/05 clinical trial. Promising candidate biomarkers were orthogonally validated with quantitative immunofluorescence (QIF). RNA-sequencing data from the Neoadjuvant Lapatinib and/or Trastuzumab Treatment Optimisation Study (NeoALTTO) were accessed to provide independent cohort validation. Disease-free survival (DFS) was the main outcome assessed. Statistical analyses were performed using a two-sided test (α = 0.05) and multiple testing correction (Benjamini-Hochberg method, FDR < 0.1).

RESULTS

By DSP, high expression of alpha-smooth muscle actin (α-SMA), both in the leukocyte and stromal compartments, was associated with shorter DFS in univariate analysis (P = 0.002 and P = 0.023, respectively). High α-SMA expression in the stroma was validated by QIF after controlling for estrogen receptor and progesterone receptor status [HR, 3.12; 95% confidence interval (CI), 1.12-8.68; P = 0.029] showing recurrence on trastuzumab in the same cohort. In the NeoALTTO cohort, elevated levels of ACTA2 were predictive for shorter DFS in the multivariate analysis (HR, 3.21; 95% CI, 1.14-9.05; P = 0.027).

CONCLUSIONS

This work identifies α-SMA as a novel, easy-to-implement biomarker of resistance to trastuzumab that may be valuable in settings where trastuzumab is combined with other therapies.

Drug-induced pulmonary toxicity in breast cancer patients treated with systemic therapy: a systematic literature review

INTRODUCTION

Drug-induced pulmonary toxicity (DIPT) associated with breast cancer (BC) therapy has been a major concern in recent times. DIPT may not be attributed to a single type of therapy because of the concomitant use of other anticancer drugs or along with radiotherapy, which is an independent risk factor for pulmonary toxicity.

AREAS COVERED

In this systematic literature review, we evaluated the probable cause and prevalence of DIPT in various systemic therapies used in BC treatment. A literature search was conducted in PubMed, Embase and Cochrane database, up to October 2020. Clinical studies reporting DIPT and related clinical manifestations due to systemic therapy in BC treatment were included. A total of 1749 articles were retrieved, and 193 articles were included.

EXPERT OPINION

: The leading cause of DIPT among patients with BC was targeted therapy followed by chemotherapy containing regimens. A total of 17 studies reported 35 deaths (15 deaths in chemotherapy) due to DIPT. Physicians must take extra precaution while prescribing systemic therapy known to be associated with DIPT and need to be familiar with early diagnosis of DIPT in order to avoid respiratory-related complications during treatment in BC patients.

Androgen Receptor and PIM1 Expression in Tumor Tissue of Patients With Triple-negative Breast Cancer

BACKGROUND/AIM

Effective targeted therapies for triple-negative breast cancer (TNBC) are limited. In a subset of TNBC, androgen receptor (AR) plays an important role, while the human proviral integration site for Moloney murine leukemia virus-1 (PIM1) overexpression is also implicated. PIM1 kinases phosphorylate AR, thus regulating its transcriptional activity, regardless of the presence or not of androgens. We evaluated the expression of AR and PIM1 and their prognostic significance in TNBC.

MATERIALS AND METHODS

AR and PIM1 transcripts were quantified by quantitative reverse transcription polymerase chain reaction in formalin-fixed paraffin-embedded tumor from 141 patients with TNBC.

RESULTS

AR was expressed in 38.3%, PIM1 in 10.6%, while co-expression of AR and PIM1 was detected in 7/141 cases (5.0%). No prognostic significance of AR or PIM1 was reached for overall or disease-free survival.

CONCLUSION

Co-expression of AR and PIM1 exists in only in a small percentage of patients with TNBC. The implications of this finding in the therapeutic management of patients with TNBC should be investigated in larger patient cohorts.

Quality of adverse event reporting in phase III randomized controlled trials of breast and colorectal cancer: A systematic review

BACKGROUND

Clinical trial reports often emphasize efficacy over harms, leading to misinterpretation of the risk-to-benefit ratio of new therapies. Clear and sufficiently detailed reporting of methods and results is especially important in the abstracts of trial reports, as readers often base their assessment of a trial on such information. In this study, we evaluated the quality of adverse event (AE) reporting and abstract quality in phase III randomized controlled trials (RCTs) of systemic therapies in breast and colorectal cancer.

METHODS

Medline, EMBASE, Cochrane Database of RCTs, and Cochrane Database of Systematic Reviews were searched from November 2005 to September 2018. Phase III RCTs evaluating systemic therapies in breast or colorectal cancer were included. Each article was independently reviewed by two investigators using a standardized data extraction form based on guidelines developed by the Consolidated Standards of Reporting Trials (CONSORT) group. Descriptive statistics, bivariate analysis, and multivariable linear regression were used to analyze data. All statistical tests were two-sided.

RESULTS

Of 166 RCTs identified, 99.4% reported harms in the manuscript body, and 59.6% reported harms in the abstract. Reporting was restricted to severe harms in 15.6% of RCTs. Statistical comparison of AE rates went unreported in 59.0% of studies. Information regarding AEs leading to dose reductions, treatment discontinuations, or study withdrawals went unreported in 59.3%, 18.7%, and 86.8% of studies, respectively. Recently published RCTs (P = .009) and those sponsored at least partially by for-profit companies (P = .003) had higher abstract quality scores.

CONCLUSIONS

Breast and colorectal cancer phase III RCTs inadequately report CONSORT-compliant AE data. Improved guideline adherence and abstract reporting is required to properly weigh benefits and harms of new oncologic therapies.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42019140673.

Efficacy and safety of tailored and dose-dense adjuvant chemotherapy and trastuzumab for resected HER2-positive breast cancer: Results from the phase 3 PANTHER trial

BACKGROUND

Dose-dense (DD) adjuvant chemotherapy improves outcomes in early breast cancer (BC). However, there are no phase 3 randomized data to inform on its combination with trastuzumab for patients with human epidermal growth factor receptor 2 (HER2)-positive disease.

METHODS

This was a protocol-predefined secondary analysis of the randomized phase 3 Pan-European Tailored Chemotherapy (PANTHER) trial. Women 65 years old or younger with node-positive or high-risk, node-negative BC were randomized 1:1 to either tailored (according to hematologic nadirs) and DD epirubicin and cyclophosphamide followed by docetaxel or standard 5-fluorouracil, epirubicin, and cyclophosphamide plus docetaxel every 3 weeks. Patients with HER2-positive disease received 1 year of adjuvant trastuzumab. The primary endpoint was BC relapse-free survival. In addition, HER2-positive patients and an equal number of HER2-negative patients matched for age, treatment group, and institution who were enrolled at Swedish sites were asked to participate in a predefined study of cardiac safety and underwent echocardiography or multigated acquisition scanning and electrocardiography at the baseline and at 4 and 6 years of follow-up.

RESULTS

There were 342 HER2-positive patients; 335 received at least 1 dose of trastuzumab, and 29 patients discontinued trastuzumab prematurely. Relapse-free survival was not statistically significantly in favor of the tailored and DD group (hazard ratio, 0.68; 95% confidence interval, 0.37-1.27; P = .231). Cardiac outcomes after 4 and 6 years of follow-up did not differ significantly between HER2-positive and HER2-negative patients or between the 2 treatment groups.

CONCLUSIONS

The combination of DD chemotherapy and trastuzumab decreased the relative risk for relapse by 32% in comparison with standard treatment, a statistically nonsignificant difference. Its efficacy and safety merit further evaluation as part of both escalation and de-escalation strategies.

Dose-dense adjuvant chemotherapy in HER2-positive early breast cancer patients before and after the introduction of trastuzumab: Exploratory analysis of the GIM2 trial

Dose-dense adjuvant chemotherapy is standard of care in high-risk early breast cancer patients. However, its role in HER2-positive patients is still uncertain. In this exploratory analysis of the GIM2 trial, we investigated the efficacy of dose-dense chemotherapy in HER2-positive breast cancer patients with or without exposure to trastuzumab. In the GIM2 trial, node-positive early breast cancer patients were randomized to receive four cycles of (fluorouracil)epirubicin/cyclophosphamide followed by four cycles of paclitaxel administered every 2 (dose-dense) or 3 (standard-interval) weeks. After approval of adjuvant trastuzumab, protocol was amended in April 2006 to allow use of trastuzumab for 1 year after chemotherapy completion in HER2-positive patients. The efficacy of dose-dense chemotherapy in terms of disease-free survival (DFS) and overall survival (OS) was assessed according to HER2 status and trastuzumab use. Out of 2,003 breast cancer patients, HER2 status was negative/unknown in 1,551 patients; among the 452 patients with HER2-positive breast cancer, chemotherapy alone or followed by trastuzumab was given to 320 and 132 patients, respectively. Median follow-up was 8.1 years. No significant interaction between HER2 status, trastuzumab use and chemotherapy treatment was observed for both DFS (p = 0.698) and OS (p = 0.708). Nevertheless, there was no apparent benefit in the HER2-positive group treated with trastuzumab (DFS: HR, 0.99; 95% CI 0.52-1.89; OS: HR, 0.95; 95% CI 0.37-2.41). Although dose-dense chemotherapy was associated with a significant survival improvement in high-risk breast cancer patients, its benefit appeared to be smaller (if any) in patients with HER2-positive disease who received adjuvant trastuzumab.

Acquired Resistance to HER2-Targeted Therapies Creates Vulnerability to ATP Synthase Inhibition

Acquired resistance to HER2-targeted therapies occurs frequently in HER2⁺ breast tumors and new strategies for overcoming resistance are needed. Here, we report that resistance to trastuzumab is reversible, as resistant cells regained sensitivity to the drug after being cultured in drug-free media. RNA-sequencing analysis showed that cells resistant to trastuzumab or trastuzumab + pertuzumab in combination increased expression of oxidative phosphorylation pathway genes. Despite minimal changes in mitochondrial respiration, these cells exhibited increased expression of ATP synthase genes and selective dependency on ATP synthase function. Resistant cells were sensitive to inhibition of ATP synthase by oligomycin A, and knockdown of ATP5J or ATP5B, components of ATP synthase complex, rendered resistant cells responsive to a low dose of trastuzumab. Furthermore, combining ATP synthase inhibitor oligomycin A with trastuzumab led to regression of trastuzumab-resistant tumors in vivo. In conclusion, we identify a novel vulnerability of cells with acquired resistance to HER2-targeted antibody therapies and reveal a new therapeutic strategy to overcome resistance. SIGNIFICANCE: These findings implicate ATP synthase as a novel potential target for tumors resistant to HER2-targeted therapies.

Opposite Prognostic Impact of Single PTEN-loss and PIK3CA Mutations in Early High-risk Breast Cancer

BACKGROUND/AIM

PTEN-loss and PIK3CA mutations have been addressed as markers of PI3K activation in breast cancer. We evaluated these markers in early high-risk breast cancer (EBC) focusing on PTEN immunohistochemistry (IHC) issues, particularly in HER2-positive disease.

MATERIALS AND METHODS

We examined PTEN-loss and PIK3CA mutations in 1265 EBC patients treated with adjuvant chemotherapy within two clinical trials. Two different methods for the evaluation of PTEN IHC were used, one upfront binary (loss; no-loss) and the other initially multi-scale allowing for the classification of "grey zone" tumors with low and very low PTEN protein expression.

RESULTS

PTEN-loss (33.4% and 22.1%, depending on the IHC method) and PIK3CA mutations (29.6%) were associated with ER/PgR/HER2-negative and ER/PgR-positive disease, respectively. Concordance of the two IHC methods was moderate (Cohen's kappa 0.624). PTEN-loss discrepancy and intra-tumor heterogeneity concerned "grey zone" tumors that were prevalent among HER2-positive cancers. PTEN-loss independently conferred higher risk for relapse and death. Compared to single PIK3CA mutations,single PTEN-loss was independently associated with increased risk for relapse and death. Depending on the evaluation method, in HER2-positive cancer, PTEN-loss was without- or of marginal unfavorable prognostic significance.

CONCLUSION

In EBC, PTEN-loss is an independent predictor of poor outcome. When occurring singly, PTEN-loss and PIK3CA mutations have opposite prognostic impact. In HER2-positive disease, assessment of PTEN-loss by IHC appears unreliable and the marker is without clear prognostic significance.

Multiplexed (18-Plex) Measurement of Signaling Targets and Cytotoxic T Cells in Trastuzumab-Treated Patients using Imaging Mass Cytometry

PURPOSE

Imaging mass cytometry (IMC) uses metal-conjugated antibodies to provide multidimensional, objective measurement of protein targets. We used this high-throughput platform to perform an 18-plex assessment of HER2 ICD/ECD, cytotoxic T-cell infiltration and other structural and signaling proteins in a cohort of patients treated with trastuzumab to discover associations with trastuzumab benefit.

EXPERIMENTAL DESIGN

An antibody panel for detection of 18 targets (pan-cytokeratin, HER2 ICD, HER2 ECD, CD8, vimentin, cytokeratin 7, β-catenin, HER3, MET, EGFR, ERK 1-2, MEK 1-2, PTEN, PI3K p110 α, Akt, mTOR, Ki67, and Histone H3) was used with a selection of trastuzumab-treated patients from the Hellenic Cooperative Oncology Group 10/05 trial (n = 180), and identified a case-control series.

RESULTS

Patients that recurred after adjuvant treatment with trastuzumab trended toward a decreased fraction of HER2 ECD pixels over threshold compared with cases without recurrence (P = 0.057). After exclusion of the lowest HER2 expressers, 5-year recurrence events were associated with reduced total extracellular domain (ECD)/intracellular domain (ICD) ratio intensity in tumor (P = 0.044). These observations are consistent with our previous work using quantitative immunofluorescence, but represent the proof on identical cell content. We also describe the association of the ECD of HER2 with CD8 T-cell infiltration on the same slide.

CONCLUSIONS

The proximity of CD8 cells as a function of the expression of the ECD of HER2 provides further evidence for the role of the immune system in the mechanism of action of trastuzumab.

lncRNA GHET1 knockdown suppresses breast cancer activity in vitro and in vivo

Long non-coding RNA gastric carcinoma high-expressed transcript 1 (lncRNA GHET1) is highly expressed in many tumors. The aim of the present study was to determine whether GHET1 inhibition decreases growth and metastasis of MCF-7 breast cancer cells by modulating epidermal growth factor receptor (EGFR) expression. In vitro, lncRNA GHET1 knockdown suppressed cell proliferation, migration, and invasion and enhanced cell apoptosis by maintaining MCF-7 cells in the G1 phase of the cell cycle. Furthermore, lncRNA GHET1 knockdown reduced the expression of EGFR and related proteins. Treatment of mice with a GHET1 inhibitor prevented tumor growth in vivo. The results indicate that lncRNA GHET1 inhibition directly suppresses EGFR expression, significantly inhibiting the downstream PI3K/AKT/Cyclin D1/MMP2/9 pathway. This mechanism may underlie the suppression of breast cancer cell activities including proliferation, migration, and invasion. In conclusion, lncRNA GHET1 knockdown suppresses tumor growth and metastasis by suppressing the activity of EGFR and downstream pathways.

TP53 mutations and protein immunopositivity may predict for poor outcome but also for trastuzumab benefit in patients with early breast cancer treated in the adjuvant setting

BACKGROUND

We investigated the impact of PIK3CA and TP53 mutations and p53 protein status on the outcome of patients who had been treated with adjuvant anthracycline-taxane chemotherapy within clinical trials in the pre- and post-trastuzumab era.

RESULTS

TP53 and PIK3CA mutations were found in 380 (21.5%) and 458 (25.9%) cases, respectively, including 104 (5.9%) co-mutated tumors; p53 immunopositivity was observed in 848 tumors (53.5%). TP53 mutations (p < 0.001) and p53 protein positivity (p = 0.001) were more frequent in HER2-positive and triple negative (TNBC) tumors, while PIK3CA mutations were more frequent in Luminal A/B tumors (p < 0.001). TP53 mutation status and p53 protein expression but not PIK3CA mutation status interacted with trastuzumab treatment for disease-free survival; patients with tumors bearing TP53 mutations or immunopositive for p53 protein fared better when treated with trastuzumab, while among patients treated with trastuzumab those with the above characteristics fared best (interaction p = 0.017 for mutations; p = 0.015 for IHC). Upon multivariate analysis the above interactions remained significant in HER2-positive patients; in the entire cohort, TP53 mutations were unfavorable in patients with Luminal A/B (p = 0.003) and TNBC (p = 0.025); p53 immunopositivity was strongly favorable in patients treated with trastuzumab (p = 0.009).

MATERIALS AND METHODS

TP53 and PIK3CA mutation status was examined in 1766 paraffin tumor DNA samples with informative semiconductor sequencing results. Among these, 1585 cases were also informative for p53 protein status assessed by immunohistochemistry (IHC; 10% positivity cut-off).

CONCLUSIONS

TP53 mutations confer unfavorable prognosis in patients with Luminal A/B and TNBC tumors, while p53 immunopositivity may predict for trastuzumab benefit in the adjuvant setting.

Correlation of MYC Gene and Protein Status With Breast Cancer Subtypes and Outcome of Patients Treated With Anthracycline-Based Adjuvant Chemotherapy. Pooled Analysis of 2 Hellenic Cooperative Group Phase III Trials

BACKGROUND

The prognostic/predictive value of aberrant MYC gene copies and protein expression is not clear in breast cancer.

PATIENTS AND METHODS

Early breast cancer patients were treated with anthracycline-containing chemotherapy within 2 randomized adjuvant trials. MYC gene and centromere-8 status, as well as Myc protein expression were investigated on 1060 paraffin tumors with fluorescence in situ hybridization and immunohistochemistry, respectively.

RESULTS

MYC amplification was present in 45% and polysomy-8 in 23% of the tumors. Cytoplasmic staining was observed in 60% and nuclear staining in 26% of the tumors, strongly correlating with each other but not with MYC gene status. MYC gene amplification in the absence of polysomy-8 was associated with adverse disease-free survival (DFS) and overall survival (OS), and remained as an independent unfavorable prognostic factor in multivariate analysis (Wald P = .022 for DFS; P = .032 for OS), whereas patients with MYC amplification and polysomy-8, with polysomy-8 only, and with normal MYC without polysomy-8 performed significantly better compared with those with MYC gene amplification only. Nuclear Myc protein expression benefitted patients treated with paclitaxel (interaction P = .052 for DFS; P = .049 for OS). This interaction remained independently significant in multivariate analysis for OS (overall P = .028).

CONCLUSION

The effect of MYC gene status on breast cancer patient outcome seems to depend on the underlying chromosomal instability and appears unfavorable for tumors with MYC amplification without polysomy. Nuclear Myc protein expression seems predictive for benefit from adjuvant paclitaxel. These data might aid in the interpretation of relevant findings from large clinical trials.

Tumors with high-density tumor infiltrating lymphocytes constitute a favorable entity in breast cancer: a pooled analysis of four prospective adjuvant trials

BACKGROUND

Tumor infiltrating lymphocytes (TILs) are considered in the prognosis of breast cancer (BC) patients. Here, we investigated the prognostic/predictive effect of TILs in patients treated in the frame of four prospective trials with adjuvant anthracycline-based chemotherapy in the pre- and post-trastuzumab era.

METHODS

TILs density was histologically assessed as percentage of stromal area on whole routine sections of 2613 BC (1563 Luminal A/B; 477 Luminal HER2; 246 HER2-enriched; 327 triple negative [TNBC]) and were evaluated as high/low at three cut-offs (c/o; 50% [lymphocytic predominance, LP], 35% and 25%), in separate training and validation sets.

RESULTS

High TILs were present in 3.5%, 6.5% and 11.5% of all tumors, using the 50%, 35% and 25% c/o, respectively. TILs status did not interact with BC subtypes or trastuzumab treatment. LPBC patient outcome was not affected by nodal status, while high TILs were favorable in TNBC with unfavorable nodal status. When adjusted for standard clinicopathological parameters and treatment, high TILs independently predicted for favorable outcome, e.g., disease-free survival with the 35% c/o in the entire cohort (HR = 0.44, 95% CI 0.28-0.69, p < 0.001) and in specific subtypes.

CONCLUSIONS

High TILs tumors, especially LPBC seem worthy validating as a separate entity of favorable prognosis in breast cancer.

Delay in initiation of adjuvant trastuzumab therapy leads to decreased overall survival and relapse-free survival in patients with HER2-positive non-metastatic breast cancer

Trastuzumab reduces the risk of relapse in women with HER2-positive non-metastatic breast cancer, but little information exists on the timing of trastuzumab initiation. The study investigated the impact of delaying the initiation of adjuvant trastuzumab therapy for >6 months after the breast cancer diagnosis on time to relapse, overall survival (OS), and relapse-free survival (RFS) among patients with non-metastatic breast cancer. Adult women with non-metastatic breast cancer who initiated trastuzumab adjuvant therapy without receiving any neoadjuvant therapy were selected from the US Department of Defense health claims database from 01/2003 to 12/2012. Two study cohorts were defined based on the time from breast cancer diagnosis to trastuzumab initiation: >6 months and ≤6 months. The impact of delaying trastuzumab initiation on time to relapse, OS, and RFS was estimated using Cox regression models adjusted for potential confounders. Of 2749 women in the study sample, 79.9 % initiated adjuvant trastuzumab within ≤6 months of diagnosis and 20.1 % initiated adjuvant trastuzumab >6 months after diagnosis. After adjusting for confounders, patients who initiated trastuzumab >6 months after the breast cancer diagnosis had a higher risk of relapse, death, or relapse/death than those who initiated trastuzumab within ≤6 months of diagnosis (hazard ratios [95 % CIs]: 1.51 [1.22-1.87], 1.54 [1.12-2.12], and 1.43 [1.16-1.75]; respectively). The results of this population-based study suggest that delays of >6 months in the initiation of trastuzumab among HER2-positive non-metastatic breast cancer patients are associated with a higher risk of relapse and shorter OS and RFS.

Survival in patients with non-metastatic breast cancer treated with adjuvant trastuzumab in clinical practice

PURPOSE

The NSABP Trial B-31 and NCCTG Trial N9831 (B-31/N9831 trials, Romond et al. in N Engl J Med 353:1673-84, 2005. doi:10.1056/NEJMoa052122; Perez et al. in J Clin Oncol 32:3744-52, 2014. doi:10.1200/JCO.2014.55.5730) established the efficacy of adjuvant trastuzumab for patients with HER2-positive early stage breast cancer. We aimed to estimate the overall survival (OS) and relapse-free survival (RFS) of HER2-positive non-metastatic breast cancer patients treated with adjuvant trastuzumab in a clinical practice setting in the United States.

METHODS

Adult women initiating adjuvant trastuzumab within 1 year of breast cancer surgery were identified in the health claims database of the US Department of Defense (01/2003-12/2012). OS and RFS unadjusted rates at 4 and 6 years after the first trastuzumab treatment following the breast cancer diagnosis were estimated from Kaplan-Meier analyses.

RESULTS

The study sample included 3188 women followed for a median of 3.3 years after trastuzumab initiation and treated continuously with trastuzumab for a median of 12 months. The OS rates (95 % confidence intervals) at 4 and 6 years were 90.0 % (88.6-91.2) and 87.1 (85.3-88.6), respectively. The corresponding RFS rates were 75.8 % (74.0-77.5) and 72.7 (70.7-74.7), respectively. The OS and RFS rates at 6 years reported in the B-31/N9831 trials were 89.8 and 81.4 %, respectively.

CONCLUSIONS

OS rates estimated in this study were in range with those estimated in the B-31/N9831 trials, while RFS rates were lower. However, patients in the B-31/N9831 trials were younger and possibly had fewer comorbidities than patients in the current study; these differences were not adjusted for in the crude OS and RFS analyses.

Safety and Tolerability of Anthracycline-Containing Adjuvant Chemotherapy in Elderly High-Risk Breast Cancer Patients

BACKGROUND

Intensive chemotherapy confers benefit to patients with high-risk early breast cancer (BC). We characterized the feasibility and toxicity profile of anthracycline-containing adjuvant chemotherapy (ACAC) in older women with early BC.

PATIENTS AND METHODS

Available data from women who received ACAC for BC in 3 randomized trials were retrieved. We identified women aged >65 years and we examined differences in tolerability and delivery of chemotherapy, toxicity, and treatment outcome.

RESULTS

From a total of 2640 patients, we identified 453 patients (17%) as being >65 years old, 89% of whom had tumors that were node-positive, with 77% who were hormone receptor-positive. At least 90% of the planned doses were delivered in 37% of the elderly, compared with 49% in the younger patients (P < .0001). Grade 3 and 4 hematological toxicity was observed in 32% of elderly patients, compared with 21% of the younger (P < .0001). Febrile neutropenia occurred in 4.5% of the elderly patients, as opposed to 2.0% in the younger patients (P < .002). Elderly patients experienced more frequent Grade 3 and 4 fatigue, mucositis, and sensory neuropathy. Relative dose intensities were significantly lower in elderly patients. Treatment discontinuation was not different in the 2 groups. At a median follow-up of 120 months, competing risks analysis showed a significant benefit in disease-free survival for elderly patients.

CONCLUSION

Elderly BC patients treated with ACAC derive clinical benefit comparable to that in younger patients, mainly at the cost of increased risk of hematological toxicity. This should be taken into account in decision-making and treatment individualization in high-risk BC patients.

Evaluation of two highly-multiplexed custom panels for massively parallel semiconductor sequencing on paraffin DNA

BACKGROUND

AIM

Massively parallel sequencing (MPS) holds promise for expanding cancer translational research and diagnostics. As yet, it has been applied on paraffin DNA (FFPE) with commercially available highly multiplexed gene panels (100s of DNA targets), while custom panels of low multiplexing are used for re-sequencing. Here, we evaluated the performance of two highly multiplexed custom panels on FFPE DNA.

METHODS

Two custom multiplex amplification panels (B, 373 amplicons; T, 286 amplicons) were coupled with semiconductor sequencing on DNA samples from FFPE breast tumors and matched peripheral blood samples (n samples: 316; n libraries: 332). The two panels shared 37% DNA targets (common or shifted amplicons). Panel performance was evaluated in paired sample groups and quartets of libraries, where possible.

RESULTS

Amplicon read ratios yielded similar patterns per gene with the same panel in FFPE and blood samples; however, performance of common amplicons differed between panels (p<0.001). FFPE genotypes were compared for 1267 coding and non-coding variant replicates, 999 out of which (78.8%) were concordant in different paired sample combinations. Variant frequency was highly reproducible (Spearman's rho 0.959). Repeatedly discordant variants were of high coverage / low frequency (p<0.001). Genotype concordance was (a) high, for intra-run duplicates with the same panel (mean±SD: 97.2±4.7, 95%CI: 94.8-99.7, p<0.001); (b) modest, when the same DNA was analyzed with different panels (mean±SD: 81.1±20.3, 95%CI: 66.1-95.1, p = 0.004); and (c) low, when different DNA samples from the same tumor were compared with the same panel (mean±SD: 59.9±24.0; 95%CI: 43.3-76.5; p = 0.282). Low coverage / low frequency variants were validated with Sanger sequencing even in samples with unfavourable DNA quality.

CONCLUSIONS

Custom MPS may yield novel information on genomic alterations, provided that data evaluation is adjusted to tumor tissue FFPE DNA. To this scope, eligibility of all amplicons along with variant coverage and frequency need to be assessed.

Measurement of Domain-Specific HER2 (ERBB2) Expression May Classify Benefit From Trastuzumab in Breast Cancer

BACKGROUND

Studies have shown that antibodies targeting the intracellular (ICD) or extracellular domains (ECD) of human epidermal growth factor receptor 2 (HER2) are equivalent when traditional methods are used. We describe a new method to quantify ICD and ECD expression separately and assess the prognostic value of domain-specific HER2 results in patients who received adjuvant trastuzumab therapy.

METHODS

We measured HER2 protein expression with quantitative immunofluorescence (QIF) in tissue microarrays (TMA) using two different antibodies targeting the ICD (CB11 and A0485) and ECD (SP3 and D8F12). We assessed the prognostic value of ICD and ECD expression in 180 patients from a clinical trial of adjuvant chemotherapy followed by trastuzumab (HeCOG 10/05). We performed an exploratory univariate domain-specific, disease-free survival (DFS) analysis and compared DFS functions with Kaplan-Meier estimates. All statistical tests were two-sided.

RESULTS

HER2 ICD expression by QIF showed slightly higher sensitivity to predict ERBB2 (HER2) gene amplification than ECD expression, which was more specific and had higher positive predictive value. In the HeCOG 10/05 trial specimens, 15% of cases showed discordant results for ICD and ECD expression. High ECD was statistically associated with longer DFS (log-rank P = .049, HR = 0.31, 95% CI = 0.144 to 0.997), while ICD status was not. Among patients with low ECD, there was no difference in DFS by ICD status. However, when ICD was high, high ECD was statistically associated with longer DFS (log-rank P = .027, HR = 0.23, 95% CI = 0.037 to 0.82) compared with low ECD.

CONCLUSION

Quantitative measurements of HER2 ICD and ECD expression in breast cancer suggest a subclassification of HER2-positive tumors. Trastuzumab-treated patients with high ECD showed better DFS than patients with low ECD. This suggests differential benefit from trastuzumab therapy based on HER2 ECD expression.

Gambogic Acid lysinate induces apoptosis in breast cancer mcf-7 cells by increasing reactive oxygen species

Gambogic acid (GA) inhibits the proliferation of various human cancer cells. However, because of its water insolubility, the antitumor efficacy of GA is limited. Objectives. To investigate the antitumor activity of gambogic acid lysinate (GAL) and its mechanism. Methods. Inhibition of cell proliferation was determined by MTT assay; intracellular ROS level was detected by staining cells with DCFH-DA; cell apoptosis was determined by flow cytometer and the mechanism of GAL was investigated by Western blot. Results. GAL inhibited the proliferation of MCF-7 cells with IC₅₀ values 1.46 μmol/L comparable with GA (IC₅₀, 1.16 μmol/L). GAL promoted the production of ROS; however NAC could remove ROS and block the effect of GAL. GAL inhibited the expression of SIRT1 but increased the phosphorylation of FOXO3a and the expression of p27Kip1. At knockdown of FOXO3a, cell apoptosis induced by GAL can be partly blocked. In addition it also enhanced the cleavage of caspase-3. Conclusions. GAL inhibited MCF-7 cell proliferation and induced MCF-7 cell apoptosis by increasing ROS level which could induce cell apoptosis by both SIRT1/FOXO3a/p27Kip1 and caspase-3 signal pathway. These results suggested that GAL might be useful as a modulation agent in cancer chemotherapy.