Immunogenicity and efficacy of pembrolizumab and doxorubicin in a phase I trial for patients with metastatic triple-negative breast cancer.

Currently there is a limited understanding for the optimal combination of immune checkpoint inhibitor and chemotherapy for patients with metastatic triple-negative breast cancer (mTNBC). Here we evaluate the safety, efficacy, and immunogenicity of a phase I trial for patients with mTNBC treated with pembrolizumab plus doxorubicin. Patients without prior anthracycline use and 0-2 lines of prior systemic chemotherapies received pembrolizumab and doxorubicin every 3 weeks for 6 cycles followed by pembrolizumab maintenance until disease progression or intolerance. The primary objectives were safety and objective response rate per RECIST 1.1. Best responses included one complete response (CR), five partial responses (PR), two stable disease (SD), and one progression of disease (PD). Overall response rate was 67% (95% CI 13.7%, 78.8%) and clinical benefit rate at 6 months was 56% (95% CI 21.2%, 86.3%). Median PFS was 5.2 months (95% CI 4.7, NA); median OS was 15.6 months (95% CI 13.3, NA). Grade 3-4 AEs per CTCAE 4.0 were neutropenia n = 4/10 (40%), leukopenia n = 2/10 (20%), lymphopenia n = 2/10 (20%), fatigue n = 2/10 (20%), and oral mucositis n = 1/10 (10%). Immune correlates showed increased frequencies of circulating CD3 + T cells (p = 0.03) from pre-treatment to cycle 2 day 1 (C2D1). An expansion of a proliferative exhausted-like PD-1 + CD8 + T cell population was identified in 8/9 patients, and exhausted CD8 + T cells were significantly expanded from pre-treatment to C2D1 in the patient with CR (p = 0.01). In summary, anthracycline-naïve patients with mTNBC treated with the combination of pembrolizumab and doxorubicin showed an encouraging response rate and robust T cell response dynamics.Trial registration: NCT02648477.

Antibody-Drug Conjugates in Breast Cancer: Current Status and Future Directions.

Antibody drug conjugates (ADCs) are novel medications that combine monoclonal antibodies with cytotoxic payloads, enabling the selective delivery of potent drugs to cancer cells expressing specific surface antigens. This targeted strategy seeks to optimize treatment effectiveness while reducing the risk of systemic toxicity, distinguishing ADCs from conventional chemotherapy. The rapid growth in ADC research has led to numerous developments and approvals for cancer treatment, with significant impacts on the management of breast cancer. ADCs like T-DXd for HER2-low disease and sacituzumab govitecan for triple negative breast cancer (TNBC) have provided valuable options for challenging subtypes of breast cancer. However, essential questions still need to be addressed, including the optimal order of ADCs amidst the growing number of newly developed ones and strategies to overcome resistance mechanisms. Preclinical studies have shed light on potential resistance mechanisms, emphasizing the potential benefit of combinational approaches with other agents such as immune checkpoint inhibitors (ICIs) and targeted tyrosine kinase inhibitors (TKIs) to enhance treatment effectiveness. Additionally, personalized approaches based on molecular profiling hold promise in tailoring ADC treatments to individual tumors, identifying unique molecular markers for each patient to optimize treatment efficacy while minimizing side effects.

CDK4/6 Inhibitor Resistance in Hormone Receptor-Positive Metastatic Breast Cancer: Translational Research, Clinical Trials, and Future Directions.

The emergence of CDK4/6 inhibitors, such as palbociclib, ribociclib, and abemaciclib, has revolutionized the treatment landscape for hormone receptor-positive breast cancer. These agents have demonstrated significant clinical benefits in terms of both progression-free survival and overall survival. However, resistance to CDK4/6 inhibitors remains a challenge, limiting their long-term efficacy. Understanding the complex mechanisms driving resistance is crucial for the development of novel therapeutic strategies and the improvement of patient outcomes. Translational research efforts, such as preclinical models and biomarker studies, offer valuable insight into resistance mechanisms and may guide the identification of novel combination therapies. This review paper aims to outline the reported mechanisms underlying CDK4/6 inhibitor resistance, drawing insights from both clinical data and translational research in order to help direct the future of treatment for hormone receptor-positive metastatic breast cancer.

The blood level of thioredoxin 1 as a supporting biomarker in the detection of breast cancer.

BACKGROUND: There is a long-time unmet need for a means to detect breast cancer (BC) using blood. Although mammography is accepted as the gold standard for screening, a blood-based diagnostic can complement mammography and assist in the accurate detection of BC in the diagnostic process period of early diagnosis. We have previously reported the possible use of thioredoxin 1 (Trx1) in serum as a novel means to detect BC. In the present study, we validated the clinical utility of Trx1 to identify BC by testing sera from biopsy-confirmed cancer patients and women without cancer. METHODS: We have generated monoclonal antibodies against Trx1 and developed an ELISA kit that can quantitate Trx1 in sera. The level of Trx1 was determined in each serum from women without cancer (n = 114), as well as in serum from patients with BC (n = 106) and other types of cancers (n = 74), including cervical, lung, stomach, colorectal, and thyroid cancer. The sera from BC patients were collected and classified by the subjects' age and cancer stage. In addition to the Trx1 levels of BC patients, several pathological and molecular aspects of BC were analyzed. Test results were retrospectively compared to those from mammography. Each test was duplicated, and test results were analyzed by ROC analysis, one-way ANOVA tests, and unpaired t-tests. RESULTS: The mean level of Trx1 from women without cancer was 5.45 ± 4.16 (±SD) ng/ml, that of the other malignant cancer patient group was 2.70 ± 2.01 ng/ml, and that from the BC group was 21.96 ± 6.79 ng/ml. The difference among these values was large enough to distinguish BC sera from non-BC control sera with a sensitivity of 97.17% and specificity of 94.15% (AUC 0.990, p < 0.0001). Most Trx1 levels from BC patients' sera were higher than the cut-off value of 11.4 ng/ml regardless of age, stage, histological grade, type, and specific receptors' expression profile of BC. The level of Trx1 could rescue women from most cases of misread or incomplete mammography diagnoses. CONCLUSION: These results indicated that the blood level of Trx1 could be an effective and accurate means to assist the detection of BC during the early diagnosis period.

Phase II Trial of Neoadjuvant Carboplatin and Nab-Paclitaxel in Patients with Triple-Negative Breast Cancer.

BACKGROUND: In this phase II clinical trial, we evaluated the efficacy of the nonanthracycline combination of carboplatin and nab-paclitaxel in early stage triple-negative breast cancer (TNBC). PATIENTS AND METHODS: Patients with newly diagnosed stage II-III TNBC (n = 69) were treated with neoadjuvant carboplatin (area under the curve 6) every 28 days for four cycles plus nab-paclitaxel (100 mg/m2 ) weekly for 16 weeks. Pathological complete response (pCR) and residual cancer burden (RCB) were analyzed with germline mutation status, tumor-infiltrating lymphocytes (TILs), TNBC molecular subtype, and GeparSixto immune signature (GSIS). RESULTS: Sixty-seven patients were evaluable for safety and response. Fifty-three (79%) patients experienced grade 3/4 adverse events, including grade 3 anemia (43%), neutropenia (39%), leukopenia (15%), thrombocytopenia (12%), fatigue (7%), peripheral neuropathy (7%), neutropenia (16%), and leukopenia (1%). Twenty-four patients (35%) had at least one dose delay, and 50 patients (72%) required dose reduction. Sixty-three (94%) patients completed scheduled treatment. The responses were as follows: 32 of 67 patients (48%) had pCR (RCB 0), 10 of 67 (15%) had RCB I, 19 of 67 (28%) had RCB II, 5 of 67 (7%) had RCB III, and 1 of 67 (2%) progressed and had no surgery. Univariate analysis showed that immune-hot GSIS and DNA repair defect (DRD) were associated with higher pCR with odds ratios of 4.62 (p = .005) and 4.76 (p = .03), respectively, and with RCB 0/I versus RCB II/III with odds ratio 4.80 (p = .01). Immune-hot GSIS was highly correlated with DRD status (p = .03), TIL level (p < .001), and TNBC molecular subtype (p < .001). After adjusting for age, race, stage, and grade, GSIS remained associated with higher pCR and RCB class 0/I versus II/III with odds ratios 7.19 (95% confidence interval [CI], 2.01-25.68; p = .002) and 8.95 (95% CI, 2.09-38.23; p = .003), respectively. CONCLUSION: The combination of carboplatin and nab-paclitaxel for early stage high-risk TNBC showed manageable toxicity and encouraging antitumor activity. Immune-hot GSIS is associated with higher pCR rate and RCB class 0/1. This study provides an additional rationale for using nonanthracycline platinum-based therapy for future neoadjuvant trials in early stage TNBCs. Clinical trial identification number: NCT01525966 IMPLICATIONS FOR PRACTICE: Platinum is an important neoadjuvant chemotherapy agent for treatment of early stage triple-negative breast cancer (TNBC). In this study, carboplatin and nab-paclitaxel were well tolerated and highly effective in TNBC, resulting in pathological complete response of 48%. In univariate and multivariate analyses adjusting for age, race, tumor stage and grade, "immune-hot" GeparSixto immune signature (GSIS) and DNA repair defect (DRD) were associated with higher pathological complete response (pCR) and residual cancer burden class 0/1. The association of immune-hot GSIS with higher pCR holds promise for de-escalating neoadjuvant chemotherapy for patients with early stage TNBC. Although GSIS is not routinely used in clinic, further development of this immune signature into a clinically applicable assay is indicated.

A Phase II Clinical Trial of Pembrolizumab and Enobosarm in Patients with Androgen Receptor-Positive Metastatic Triple-Negative Breast Cancer.

LESSONS LEARNED: The combination of enobosarm and pembrolizumab was well tolerated and showed a modest clinical benefit rate of 25% at 16 weeks. Future trials investigating androgen receptor-targeted therapy in combination with immune checkpoint inhibitors are warranted. BACKGROUND: Luminal androgen receptor is a distinct molecular subtype of triple-negative breast cancer (TNBC) defined by overexpression of androgen receptor (AR). AR-targeted therapy has shown modest activity in AR-positive (AR+) TNBC. Enobosarm (GTx-024) is a nonsteroidal selective androgen receptor modulator (SARM) that demonstrates preclinical and clinical activity in AR+ breast cancer. The current study was designed to explore the safety and efficacy of the combination of enobosarm and pembrolizumab in patients with AR+ metastatic TNBC (mTNBC). METHODS: This study was an open-label phase II study for AR+ (≥10%, 1+ by immunohistochemistry [IHC]) mTNBC. Eligible patients received pembrolizumab 200 mg intravenous (IV) every 3 weeks and enobosarm 18 mg oral daily. The primary objective was to evaluate the safety of enobosarm plus pembrolizumab and determine the response rate. Peripheral blood, tumor biopsies, and stool samples were collected for correlative analysis. RESULTS: The trial was stopped early because of the withdrawal of GTx-024 drug supply. Eighteen patients were enrolled, and 16 were evaluable for responses. Median age was 64 (range 36-81) years. The combination was well tolerated, with only a few grade 3 adverse events: one dry skin, one diarrhea, and one musculoskeletal ache. The responses were 1 of 16 (6%) complete response (CR), 1 of 16 (6%) partial response (PR), 2 of 16 (13%) stable disease (SD), and 12 of 16 (75%) progressive disease (PD). Response rate (RR) was 2 of 16 (13%). Clinical benefit rate (CBR) at 16 weeks was 4 of 16 (25%). Median follow-up was 24.9 months (95% confidence interval [CI], 17.5-30.9). Progression-free survival (PFS) was 2.6 months (95% CI, 1.9-3.1) and overall survival (OS) was 25.5 months (95% CI, 10.4-not reached [NR]). CONCLUSION: The combination of enobosarm and pembrolizumab was well tolerated, with a modest clinical benefit rate of 25% at 16 weeks in heavily pretreated AR+ TNBC without preselected programmed death ligand-1 (PD-L1). Future clinical trials combining AR-targeted therapy with immune checkpoint inhibitor (ICI) for AR+ TNBC warrant investigation.

Impact of changes in perceived attentional function on postsurgical health-related quality of life in breast cancer patients awaiting adjuvant treatment.

PURPOSE: Few studies have assessed pre-surgery cognitive impairment or the impact of pre-surgery cognitive impairment on quality of life. The purpose of this study was to assess changes in perceived cognitive function from pre-surgery to 1 month post-surgery and to determine whether cognitive function predicted health-related quality of life in women who awaited adjuvant treatment for breast cancer. METHODS: This study used a descriptive pre-post design to assess women newly diagnosed with breast cancer prior to any treatment (N = 132). Cognition was assessed using the Attentional Function Index (AFI) and health-related quality of life was assessed using the Functional Assessment of Cancer Therapy-General (FACT-G). Statistical methods included descriptive, comparative and regression analyses. Covariates assessed and controlled for in analyses included depressed mood, fatigue, disturbed sleep, surgery-related symptoms (lymphedema/decreased mobility), and cultural tendency. RESULTS: Perceived attention and memory function decreased from pre-surgery to 1 month post-surgery alongside alterations in arm function and a decrease in depressed mood (p < 0.05). Regression analysis indicated that, after controlling for covariates, poorer perceived attention and memory function, surgery-specific symptoms, and a greater tendency toward collectivism predicted poorer quality of life. CONCLUSION: Perceived function on tasks requiring attention and working memory 1 month post-surgery was poorer compared to pre-surgery suggesting that the mental and physical demands of a new diagnosis of breast cancer and surgery may effect cognitive function. Additionally, changes in perceived cognitive function significantly predicted perceived quality of life in women awaiting adjuvant treatment for breast cancer. Findings suggest that breast cancer patients are at risk for an early decline in cognitive function and that interventions aimed at supporting and optimizing function may improve quality of life early in the disease trajectory.

Phase I clinical trial of the combination of eribulin and everolimus in patients with metastatic triple-negative breast cancer.

BACKGROUND: Alteration of the PI3K/AKT/mTOR pathway is a common genomic abnormality detected in triple-negative breast cancer (TNBC). Everolimus acts synergistically with eribulin in TNBC cell lines and xenograft models. This phase I trial was designed to test the safety and tolerability of combining eribulin and everolimus in patients with metastatic TNBC. METHODS: The primary objective of this study was to evaluate the safety and toxicities of the combination. Patients with metastatic TNBC who had up to four lines of prior chemotherapies were enrolled. The combination of eribulin and everolimus was tested using three dosing levels: A1 (everolimus 5 mg daily; eribulin 1.4 mg/m2 days 1 and 8 every 3 weeks), A2 (everolimus 7.5 mg daily; eribulin 1.4 mg/m2, days 1 and 8 every 3 weeks), and B1 (everolimus 5 mg daily; eribulin 1.1 mg/m2 days 1 and 8 every 3 weeks). RESULTS: Twenty-seven patients with median age 55 years were enrolled. Among 8 evaluable patients who received dose level A1, 4 had dose-limiting toxicities (DLTs). Among 3 evaluable patients treated with dose level A2, 2 had DLTs. Among 12 evaluable patients who received dose level B1, 4 had DLTs. The DLTs were neutropenia, stomatitis, and hyperglycemia. Over the study period, 59% had a ≥ grade 3 toxicity, 44% had ≥ grade 3 hematologic toxicities, and 22% had grade 4 hematologic toxicities. The most common hematological toxicities were neutropenia, leukopenia, and lymphopenia. Thirty-three percent had grade 3 non-hematologic toxicities. The most common non-hematological toxicities were stomatitis, hyperglycemia, and fatigue. The median number of cycles completed was 4 (range 0-8). Among 25 eligible patients, 9 patients (36%) achieved the best response as partial response, 9 (36%) had stable disease, and 7 (28%) had progression. The median time to progression was 2.6 months (95% CI [2.1, 4.0]), and median overall survival (OS) was 8.3 months (95% CI [5.5, undefined]). CONCLUSION: Eribulin 1.1 mg/m2 days 1 and 8 every 3 weeks with everolimus 5 mg daily was defined as the highest dose with acceptable toxicity (RP2D). The combination is safe, and efficacy is modest. A post hoc analysis showed that participants that used dexamethasone mouthwash stayed on treatment for one additional cycle. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02120469. Registered 18 April 2014.

Osteogenic Effect of Inducible Nitric Oxide Synthase (iNOS)-Loaded Mineralized Nanoparticles on Embryonic Stem Cells.

BACKGROUND/AIMS: This study investigated the effect of inducible nitric oxide synthase-loaded mineralized nanoparticles (iNOS-MNPs) on the osteogenic differentiation of mouse embryonic stem cells (ESCs). METHODS: We prepared iNOS-MNPs using an anionic block copolymer template-mediated calcium carbonate (CaCO3) mineralization process in the presence of iNOS. iNOS-MNPs were spherical and had a narrow size distribution. iNOS was stably loaded within MNPs without denaturation. In order to confirm the successful introduction of iNOS-MNPs into the cytosol of ESCs, intracellular levels of nitric oxide (NO) was determined with a fluorometric analysis. A NO effector molecule, cyclic guanosine 3',5' monophosphate (cGMP) was also quantified with a competitive enzyme immunoassay. Cell viability in response to iNOS-MNP treatment was determined using the cell counting kit-8 (CCK-8) assay. Alkaline phosphatase (ALP) activity assay, intracellular calcium quantification assay, and Alizarin red S staining for matrix mineralization were performed to investigate osteogenic differentiation of ESCs. The protein levels of Runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), and osterix (OSX) as osteogenic-related factors were also assessed by immunofluorescence staining and Western blot analysis. The complex pathways associated with iNOS-MNP-derived osteogenic differentiation of ESCs were evaluated by network-based analysis. RESULTS: Cells with iNOS-MNPs displayed a significant increase in NO and cGMP concentration compared with the control group. When cells were exposed to iNOS-MNPs, there were no adverse effects on cell viability. Importantly, iNOS-MNP uptake promoted the osteogenic differentiation of ESCs. Using transcriptome profiling, we obtained 1,836 differentially-induced genes and performed functional enrichment analysis with ClueGO and KEGG. These analyses identified significantly enriched and interconnected molecular pathways such as protein kinase activity, estrogen receptor activity, bone morphogenetic protein (BMP) receptor binding, ligand-gated ion channel activity, and phosphatidylinositol 3-phosphate binding. CONCLUSION: These findings suggest that iNOS-MNPs can induce osteogenic differentiation in ESCs by integrating complex signaling pathways.

Whole-Genome Sequencing and Genomic Analysis of a Virulent Bacteriophage Infecting Bacillus cereus.

OBJECTIVE: Infants with a weak immune system are prone to infection with Bacillus cereus, which is commonly found in natural environments. With the aim of achieving better control of this pathogenic bacterium, in the present study we characterized a new bacteriophage, ΦBC01. METHODS: Bacteriophage particles were analyzed by transmission electron microscopy. Factors influencing adsorption were identified in a double-layer plaque assay. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was conducted to determine the size of major structural proteins. The complete genome of the phage was analyzed. RESULTS: Bacteriophage particles (105.3 ± 3.1 nm icosahedral head and 208.8 ± 3.6 nm contractile tail) were identified as Myoviridae. ΦBC01 was found to have host specificity to B. cereus. Major structural proteins of ΦBC01 showed 2 well-pronounced bands of 99 and 56 kDa. The 158,385-bp genome sequence of ΦBC01 was determined: 56 of the 239 open reading frames were annotated, indicating involvement in bacteriophage DNA manipulation, cell lysis, packaging, virion structure, and other functions. CONCLUSION: Because of characterization and genotyping of a new bacteriophage from soil samples containing earthworms, this study provides a baseline for the development of alternatives to antibiotics.