Faculty Bibliography

PURPOSE/OBJECTIVE:Breast cancer and cardiovascular diseases often share the same risk factors. It is increasingly important to identify risk factors for cardiovascular (CV) events in high-risk breast cancer patients and explore optimal treatment regimens. PATIENTS AND METHODS/METHODS:Early HER2-positive breast cancer patients at our institution between January 1998 and October 2009 were reviewed. Primary outcome was late-severe-CV-event-free survival, and late severe CV events were defined as cardiovascular death, cardiomyopathy, symptomatic heart failure and myocardial infarction developing 2+ years after breast cancer diagnosis. Kaplan-Meier plots, Cox proportional hazard regressions, and restricted mean survival time were used to evaluate outcomes. RESULTS:<0.001). CONCLUSIONS:Hypertension and CAD history were independent prognostic factors for late severe CV events. Adding anti-HER2 agents to anthracycline-containing regimens did not substantially increase the risk for late severe cardiotoxicity and conferred better overall survival.

BACKGROUND:This pooled analysis of MONALEESA trials evaluated the safety of ribociclib plus endocrine therapy (RIB + ET) with a focus on dose reductions in first-line patients. METHODS:In the dose reduction analysis, data were pooled from MONALEESA-2 (all patients), MONALEESA-3 (patients receiving treatment as first-line ET) and MONALEESA-7 (patients receiving combination therapy with an NSAI as initial ET). Efficacy was analysed by ribociclib relative dose intensity (DI). Safety was analysed in all patients in the trials (except those receiving tamoxifen in MONALEESA-7) and those with/without ≥1 ribociclib dose reduction. RESULTS:Of 818 women who received first-line RIB + ET, 41.8% required ≥1 dose reduction due to AEs (most commonly, neutropenia). Median RIB relative DI in patients without and with dose reductions was 99.3% and 65.6% in MONALEESA-2, 98.4% and 67.8% in MONALEESA-3 and 98·0% and 66·3% in MONALEESA-7. Median PFS was 24.8, 24.9 and 29.6 months for patients who received ≤71% (30th percentile), 72-96% (60th percentile) and 97-100% (90th percentile) RIB relative DI, respectively. No new safety signals emerged in the pooled safety analysis. CONCLUSIONS:This analysis provides reassuring data showing that the clinical benefit of RIB is preserved when dose modifications are undertaken to manage AEs. TRIAL REGISTRATION/BACKGROUND:MONALEESA-2 (NCT01958021) first posted October 8, 2013; MONALEESA-3 (NCT02422615) first posted April 21, 2015; MONALEESA-7 (NCT02278120) first posted October 29, 2014.

We performed a high-throughput whole-genome RNAi screen to identify novel inhibitors of ciliogenesis in normal and basal breast cancer cells. Our screen uncovered a previously undisclosed, extensive network of genes linking integrin signaling and cellular adhesion to the extracellular matrix with inhibition of ciliation in both normal and cancer cells. Surprisingly, a cohort of genes encoding extracellular matrix (ECM) proteins was also identified. We characterized several ciliation inhibitory genes and showed that their silencing was accompanied by altered cytoskeletal organization and induction of ciliation, which restricts cell growth and migration in normal and breast cancer cells. Conversely, supplying an integrin ligand, vitronectin, to the ECM rescued the enhanced ciliation observed upon silencing this gene. Aberrant ciliation could also be suppressed through hyper-activation of the YAP/TAZ pathway, indicating a potential mechanistic basis for our findings. Our findings suggest an unanticipated reciprocal relationship between ciliation and cellular adhesion to the extracellular matrix and provide a resource that could vastly expand our understanding of controls involving "outside-in" and "inside-out" signaling that restrain cilium assembly.

BACKGROUND:HER2-positive metastatic breast cancer is incurable and new treatments are needed. Addition of atezolizumab to trastuzumab emtansine might potentiate anticancer immunity and enhance the HER2-targeted cytotoxic activity of trastuzumab emtansine. We aimed to test this combination in HER2-positive advanced breast cancer that had progressed after previous treatment with trastuzumab and a taxane. METHODS:The KATE2 study is a randomised, double-blind, placebo-controlled, phase 2 study at 68 centres from nine countries across Asia, Australia, North America, and western Europe. Eligible patients were adults (aged ≥18 years) with an Eastern Cooperative Oncology Group performance status of 0 or 1 and centrally confirmed, measurable, HER2-positive advanced breast cancer previously treated with trastuzumab and a taxane. Patients were randomly assigned (2:1) either trastuzumab emtansine (3·6 mg/kg of bodyweight) plus atezolizumab (1200 mg) or trastuzumab emtansine plus placebo; all study drugs were administered by intravenous infusion every 3 weeks. Randomisation was done via an interactive voice and web response system using a permuted block scheme (block size of six) and was stratified by PD-L1 status, world region, and liver metastases. Patients, investigators, and study team members were masked to treatment allocation. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02924883, and the study has been completed. FINDINGS/RESULTS:Between Sept 26, 2016, and Aug 7, 2017, 330 patients were screened for the study, of whom 202 were randomly allocated either atezolizumab (n=133) or placebo (n=69). At the recommendation of the independent data monitoring committee, treatment assignment was unmasked on Dec 11, 2017, due to futility and the numerically higher frequency of adverse events among patients assigned atezolizumab. This date was set as the clinical cutoff for the primary analysis. Median follow-up was 8·5 months (IQR 6·1-11·5) for patients assigned atezolizumab and 8·4 months (5·3-11·1) for those assigned placebo. Median progression-free survival was 8·2 months (95% CI 5·8-10·7) for patients assigned atezolizumab versus 6·8 months (4·0-11·1) for those assigned placebo (stratified hazard ratio 0·82, 95% CI 0·55-1·23; p=0·33). The most common grade 3 or worse adverse events were thrombocytopenia (17 [13%] among 132 patients who received atezolizumab vs three [4%] among 68 who received placebo), increased aspartate aminotransferase (11 [8%] vs two [3%]), anaemia (seven [5%] vs 0), neutropenia (six [5%] vs three [4%]), and increased alanine aminotransferase (six [5%] vs two [3%]). Serious adverse events occurred in 43 (33%) of 132 patients who received atezolizumab and 13 (19%) of 68 patients who received placebo. One patient who received atezolizumab died due to a treatment-related adverse event (haemophagocytic syndrome). INTERPRETATION/CONCLUSIONS:Addition of atezolizumab to trastuzumab emtansine did not show a clinically meaningful improvement in progression-free survival and was associated with more adverse events. Further study of trastuzumab emtansine plus atezolizumab is warranted in a subpopulation of patients with PD-L1-positive, HER2-positive advanced breast cancer. FUNDING/BACKGROUND:F Hoffman-La Roche.

In our previous breast cancer case control study in Hispanics, we found 14 metabolites whose levels differed between cases and controls. To validate the results, we carried out a nested case control study of 100 incident breast cancer and 100 matched healthy women identified from the Mano-A-Mano Mexican American Cohort study. With the adjustment of parity, education, birth place, language acculturation, BMI category, smoking, drinking, physical activity, and sitting time, 4 metabolites were associated with breast cancer risk: 3-hydroxyoctanoate (Odds ratio (OR) = 1.51, 95% confidence interval (CI): 1.10, 3.47), 3-hydroxybutyrate (BHBA) (OR = 1.42, 95%CI: 1.01, 3.72), linoleate (18:2n6) (OR = 1.39, 95% CI: 1.07, 4.04), and bilirubin (OR = 0.54, 95%CI: 0.42, 0.95). Then, we used 3 non-redundant metabolites, namely 3-hydroxyoctanoate, linoleate (18:2n6), and bilirubin, to generate a metabolic risk score. Increased metabolites risk score was associated with a 1.67-fold increased risk of breast cancer (OR = 1.67, 95%CI: 1.32, 3.94). And the significant association was more evident among those who were diagnosed with cancer earlier during the follow-up (≤ 5 years) than their counterparts. In conclusion, we identified four significant metabolites which may help elucidate metabolic pathways that contribute to breast carcinogenesis. Our findings warrant further replication efforts.

PURPOSE/OBJECTIVE:In the MONALEESA-3 Phase III trial of patients with hormone receptor-positive human epidermal growth factor receptor-negative advanced breast cancer, ribociclib plus fulvestrant significantly improved progression-free survival (PFS) and overall survival (OS). Here, we present patient-reported outcomes from the trial, including health-related quality of life (HRQOL). METHODS:Patients were randomized (2:1) to receive ribociclib plus fulvestrant or placebo plus fulvestrant. Time to definitive 10% deterioration (TTD) from baseline in HRQOL (global health status [GHS] from the EORTC QLQ-C30 questionnaire) and pain (BPI-SF questionnaire) were assessed using Kaplan-Meier estimates; a stratified Cox regression model was used to estimate the hazard ratio (HR) and 95% CIs. RESULTS:Deterioration ≥10% in the EORTC-QLQ-C30 GHS was observed in 33% of patients in the ribociclib group vs 34% of patients in the placebo (reference) group (HR for TTD ≥ 10% = 0.81 [95% CI, 0.62-1.1]). Similar findings were noted for TTD ≥5% (HR = 0.79 [95% CI, 0.61-1.0]) and TTD ≥15% (HR = 0.81 [95% CI, 0.60-1.08]). TTD ≥10% in emotional functioning (HR = 0.76 [95% CI, 0.57-1.01]) trended in favor of the ribociclib group, whereas results for fatigue and pain were similar between arms. TTD ≥10% in BPI-SF pain severity index score (HR = 0.77 [95% CI, 0.57-1.05]) and worst pain item score (HR = 0.81 [95% CI, 0.58-1.12]) trended in favor of ribociclib vs placebo. CONCLUSIONS:In addition to significantly prolonging PFS and OS compared with placebo plus fulvestrant, adding ribociclib to fulvestrant maintains HRQOL.

BACKGROUND:In an earlier analysis of this phase 3 trial, ribociclib plus fulvestrant showed a greater benefit with regard to progression-free survival than fulvestrant alone in postmenopausal patients with hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Here we report the results of a protocol-specified second interim analysis of overall survival. METHODS:Patients were randomly assigned in a 2:1 ratio to receive either ribociclib or placebo in addition to fulvestrant as first-line or second-line treatment. Survival was evaluated by means of a stratified log-rank test and summarized with the use of Kaplan-Meier methods. RESULTS:This analysis was based on 275 deaths: 167 among 484 patients (34.5%) receiving ribociclib and 108 among 242 (44.6%) receiving placebo. Ribociclib plus fulvestrant showed a significant overall survival benefit over placebo plus fulvestrant. The estimated overall survival at 42 months was 57.8% (95% confidence interval [CI], 52.0 to 63.2) in the ribociclib group and 45.9% (95% CI, 36.9 to 54.5) in the placebo group, for a 28% difference in the relative risk of death (hazard ratio, 0.72; 95% CI, 0.57 to 0.92; P = 0.00455). The benefit was consistent across most subgroups. In a descriptive update, median progression-free survival among patients receiving first-line treatment was 33.6 months (95% CI, 27.1 to 41.3) in the ribociclib group and 19.2 months (95% CI, 14.9 to 23.6) in the placebo group. No new safety signals were observed. CONCLUSIONS:Ribociclib plus fulvestrant showed a significant overall survival benefit over placebo plus fulvestrant in patients with hormone-receptor-positive, HER2-negative advanced breast cancer. (Funded by Novartis; MONALEESA-3 ClinicalTrials.gov number, NCT02422615.).

Long non-coding RNAs (lncRNAs) play key roles in the regulation of breast cancer initiation and progression. LncRNAs are differentially expressed in breast cancer subtypes. Basal-like breast cancers are generally poorly differentiated tumors, are enriched in embryonic stem cell signatures, lack expression of estrogen receptor, progesterone receptor, and HER2 (triple-negative breast cancer), and show activation of proliferation-associated factors. We hypothesized that lncRNAs are key regulators of basal breast cancers. Using The Cancer Genome Atlas, we identified lncRNAs that are overexpressed in basal tumors compared to other breast cancer subtypes and expressed in at least 10% of patients. Remarkably, we identified lncRNAs whose expression correlated with patient prognosis. We then evaluated the function of a subset of lncRNA candidates in the oncogenic process in vitro. Here, we report the identification and characterization of the chromatin-associated lncRNA, RP11-19E11.1, which is upregulated in 40% of basal primary breast cancers. Gene set enrichment analysis in primary tumors and in cell lines uncovered a correlation between RP11-19E11.1 expression level and the E2F oncogenic pathway. We show that this lncRNA is chromatin-associated and an E2F1 target, and its expression is necessary for cancer cell proliferation and survival. Finally, we used lncRNA expression levels as a tool for drug discovery in vitro, identifying protein kinase C (PKC) as a potential therapeutic target for a subset of basal-like breast cancers. Our findings suggest that lncRNA overexpression is clinically relevant. Understanding deregulated lncRNA expression in basal-like breast cancer may lead to potential prognostic and therapeutic applications.

PURPOSE/OBJECTIVE:Adjuvant therapy for small, node-negative HER2-positive breast cancer (HER2+ BC) is controversial. We aimed to identify the subgroup that would benefit most from adjuvant chemotherapy and trastuzumab. EXPERIMENTAL DESIGN/METHODS:We reviewed records of patients with pT1N0M0 HER2+ BC treated at our institution from January 1, 1998, through October 31, 2009. We compared three groups: A, no adjuvant chemotherapy; B, adjuvant chemotherapy only; and C, adjuvant chemotherapy with trastuzumab. We evaluated disease-free survival (DFS), overall survival (OS), distant recurrence-free survival (DRFS), and breast cancer-specific survival (BCSS) in each group. RESULTS:<0.001); improvements in DFS, OS, DRFS, and BCSS were observed with adjuvant chemotherapy plus trastuzumab in patients with tumors ≥0.8-cm diameter. Receiving adjuvant chemotherapy with trastuzumab was not associated with improved DFS, OS, or DRFS for tumors <0.8 cm. CONCLUSIONS:Adjuvant chemotherapy plus trastuzumab should be recommended for patients with pT1N0M0 HER2+ BC ≥0.8 cm in diameter; adjuvant therapy may not be necessary for tumors <0.8 cm.

PURPOSE/OBJECTIVE:Neoadjuvant CT-P6, a trastuzumab biosimilar, demonstrated equivalent efficacy to reference trastuzumab in a phase 3 trial of HER2-positive early-stage breast cancer (EBC) (NCT02162667). We report post hoc analyses evaluating pathological complete response (pCR) and breast pCR alongside additional efficacy and safety measures. METHODS:Following neoadjuvant treatment and surgery, patients received adjuvant CT-P6 or trastuzumab (6 mg/kg) every 3 weeks for ≤ 1 year. RESULTS:In total, 271 and 278 patients received CT-P6 and trastuzumab, respectively. pCR and breast pCR rates were comparable between treatment groups regardless of age, region, or clinical stage. Overall, 47.6% (CT-P6) and 52.2% (trastuzumab) of patients experienced study drug-related treatment-emergent adverse events (TEAEs), including 17 patients reporting heart failure (CT-P6: 10; trastuzumab: 7). Two CT-P6 and three trastuzumab patients discontinued adjuvant treatment due to TEAEs. CONCLUSION/CONCLUSIONS:Adjuvant CT-P6 demonstrated comparable efficacy and safety to trastuzumab at 1 year in patients with HER2-positive EBC, supporting CT-P6 and trastuzumab comparability.