Phase II Clinical Trial of Pembrolizumab and Chemotherapy Reveals Distinct Transcriptomic Profiles by Radiologic Response in Metastatic Triple-Negative Breast Cancer.

PURPOSE: A single arm, phase II trial of carboplatin, nab-paclitaxel, and pembrolizumab (CNP) in metastatic triple-negative breast cancer (mTNBC) was designed to evaluate overall response rate (ORR), progression-free survival (PFS), duration of response (DOR), safety/tolerability, overall survival (OS), and identify pathologic and transcriptomic correlates of response to therapy. PATIENTS AND METHODS: Patients with ≤2 prior therapies for metastatic disease were treated with CNP regardless of tumor programmed cell death-ligand 1 status. Core tissue biopsies were obtained prior to treatment initiation. ORR was assessed using a binomial distribution. Survival was analyzed via the Kaplan-Meier method. Bulk RNA sequencing was employed for correlative studies. RESULTS: Thirty patients were enrolled. The ORR was 48.0%: 2 (7%) complete responses (CR), 11 (41%) partial responses (PR), and 8 (30%) stable disease (SD). The median DOR for patients with CR or PR was 6.4 months [95% confidence interval (CI), 4-8.5 months]. For patients with CR, DOR was >24 months. Overall median PFS and OS were 5.8 (95% CI, 4.7-8.5 months) and 13.4 months (8.9-17.3 months), respectively. We identified unique transcriptomic landscapes associated with each RECIST category of radiographic treatment response. In CR and durable PR, IGHG1 expression was enriched. IGHG1high tumors were associated with improved OS (P = 0.045) and were concurrently enriched with B cells and follicular helper T cells, indicating IGHG1 as a promising marker for lymphocytic infiltration and robust response to chemo-immunotherapy. CONCLUSIONS: Pretreatment tissue sampling in mTNBC treated with CNP reveals transcriptomic signatures that may predict radiographic responses to chemo-immunotherapy.

Randomized phase II trial of fulvestrant alone or in combination with bortezomib in hormone receptor-positive metastatic breast cancer resistant to aromatase inhibitors: a New York Cancer Consortium trial.

The proteasome inhibitor bortezomib enhances the effect of the selective estrogen receptor (ER) downregulator (SERD) fulvestrant by causing accumulation of cytoplasmic ER aggregates in preclinical models. The purpose of this trial was to determine whether bortezomib enhanced the effectiveness of fulvestrant. One hundred eighteen postmenopausal women with ER-positive metastatic breast cancer resistant to aromatase inhibitors (AIs) were randomized to fulvestrant alone (Arm A-500 mg intramuscular (i.m.) day -14, 1, 15 in cycle 1, and day 1 of additional cycles) or in combination with bortezomib (Arm B-1.6 mg/m2 intravenous (i.v.) on days 1, 8, 15 of each cycle). The study was powered to show an improvement in median progression-free survival (PFS) from 5.4 to 9.0 months and compare PFS rates at 6 and 12 months (α=0.10, ß=0.10). Patients with progression on fulvestrant could cross over to the combination (arm C). Although there was no difference in median PFS (2.7 months in both arms), the hazard ratio for PFS in Arm B versus Arm A (referent) was 0.73 (95% confidence interval (CI)=0.49, 1.09, P=0.06, 1-sided log-rank test, significant at the prespecified 1-sided 0.10 α level). At 12 months, the PFS proportion in Arm A and Arm B was 13.6% and 28.1% (P=0.03, 1-sided χ2-test; 95% CI for difference (14.5%)=-0.06, 29.1%). Of 27 patients on arm A who crossed over to the combination (arm C), 5 (18%) were progression-free for at least 24 weeks. Bortezomib likely enhances the effectiveness of fulvestrant in AI-resistant, ER-positive metastatic breast cancer by reducing acquired resistance, supporting additional evaluation of proteasome inhibitors in combination with SERDs.

Phase II trial of patupilone in patients with brain metastases from breast cancer.

BACKGROUND: For patients with progressive breast cancer brain metastasis (BCBM) after whole brain radiotherapy (WBRT), few options exist. Patupilone is an epothilone that crosses the blood-brain barrier. We hypothesized that patupilone would produce a 35% 3-month CNS progression-free survival in women with BCBM after WBRT. METHODS: This multicenter phase II trial included 2 cohorts. Group A included women with progressive BCBM after WBRT. Group B was an exploratory cohort of patients with either leptomeningeal metastases or untreated brain metastases. The primary goal was to observe a 35% 3-month CNS progression-free survival in Group A. The sample size was 45 for Group A and 10 for Group B. Patients received patupilone 10 mg/m(2) once every 3 weeks until progression. Responses were scored according to the Macdonald criteria. RESULTS: Fifty-five patients (45 in Group A, 10 in Group B) enrolled. In Group A, the 3-month CNS progression-free survival was 27%, the median overall survival was 12.7 months, and the overall response rate was 9%. In Group B, which enrolled 5 patients with leptomeningeal disease and 5 with no prior WBRT, no responses occurred and 8 patients had CNS progression before 3 months. Systemic responses occurred in 15% of patients, including a complete response in liver metastases. Diarrhea occurred in 87% of patients; 25% had grade 3 and 4 adverse events. CONCLUSIONS: Patupilone in patients with BCBM did not meet the efficacy criteria and had significant gastrointestinal toxicity. Further study of brain-penetrant agents is warranted for patients with CNS metastases from breast cancer.

MUC1 is expressed at high frequency in early-stage basal-like triple-negative breast cancer.

Triple-negative breast cancer comprises 10% to 15% of newly diagnosed breast cancer and lacks expression of the estrogen, progesterone, and human epidermal growth factor receptor 2/neu receptors. Many such tumors are basal like, a molecular intrinsic subtype of breast cancer associated with poor clinical outcomes. Patients with early-stage basal-like triple-negative breast cancer are at a high risk for relapse and may, therefore, benefit from novel therapies, including immunotherapy. MUC1 is a tumor antigen expressed on adenocarcinomas and represents an ideal target for MUC1-based vaccination. We evaluated 52 cases of early-stage basal-like triple-negative breast cancer for MUC1 expression by immunohistochemistry. The intensity of staining was graded according to the intensity (negative [0], positive [1], or strongly positive [2]) and percentage (0%-100%) of tumor cells staining for MUC1. An overall score of 0 to 2.0 was calculated for each case by multiplying the intensity of staining by the percentage of tumor cells staining positively. Four staining patterns for MUC1 were identified: apical, cytoplasmic, membranous, and combination. Of the 52 cases of basal-like triple-negative breast cancers, 49 (94%) were positive for MUC1 expression. The mean score was 0.90 (range, 0-1.9). Cases were evenly distributed over this range, where most (67%) exhibited moderate to strong MUC1 expression (score, 0.5-1.90), 27% demonstrated weak MUC1 expression, and 6% lacked MUC1 expression. There was a significant difference in MUC1 score and percent MUC1+ cells in favor of the combination pattern. This study indicates that a large proportion of early-stage basal-like triple-negative breast cancer expresses MUC1 and provides a rationale for MUC1-based immunotherapy in this high-risk patient cohort.

A vasculature-targeting regimen of preoperative docetaxel with or without bevacizumab for locally advanced breast cancer: impact on angiogenic biomarkers.

PURPOSE: Taxanes have effects on angiogenesis causing difficulties in separating biological effects of chemotherapy from those due to angiogenesis inhibitors. This randomized phase II trial was designed to evaluate the additional biomarker effect on angiogenesis when bevacizumab is added to docetaxel. EXPERIMENTAL DESIGN: Patients with inoperable breast cancer were randomized to either 2 cycles of preoperative docetaxel (D) 35 mg/m(2) i.v. weekly for 6 weeks, followed by a 2-week break; or docetaxel with bevacizumab 10 mg/kg i.v. every other week for a total of 16 weeks (DB). Plasma and serum markers of endothelial damage, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and tumor microvessel density were assessed before treatment and at the end of each preoperative cycle. RESULTS: Forty-nine patients were randomized (DB, 24; D, 25). There was no difference in overall clinical response, progression-free survival, or overall survival. Vascular endothelial growth factor increased during treatment; more so with DB (P < 0.0001). Vascular cell adhesion molecule-1 (VCAM-1) also increased (P < 0.0001); more so with DB (P = 0.069). Intercellular adhesion molecule increased (P = 0.018) and E-selectin decreased (P = 0.006) overall. Baseline levels of VCAM-1 and E-selectin correlated with clinical response by univariate analysis. DCE-MRI showed a greater decrease in tumor perfusion calculated by initial area under the curve for the first 90 seconds in DB (P = 0.024). DCE-MRI also showed an overall decrease in tumor volume (P = 0.012). CONCLUSION: Bevacizumab plus docetaxel caused a greater increase in vascular endothelial growth factor and VCAM-1, and a greater reduction in tumor perfusion by DCE-MRI compared with docetaxel. Clinical outcomes of inoperable breast cancer were predicted by changes in VCAM-1 and E-selectin.

Optimized systemic dosing with CpG DNA enhances dendritic cell-mediated rejection of a poorly immunogenic mammary tumor in BALB/c mice.

To model a clinical trial of dendritic cell (DC) therapy of a poorly immunogenic mammary tumor, we treated BALB/c mice bearing an established TS/A mammary tumor with lysate-pulsed DCs and CpG DNA. We observed that the dose of CpG DNA required to activate DCs in vitro was insufficient to mediate tumor rejection in vivo. We therefore undertook in vivo studies to identify an optimized dose of CpG DNA for tumor therapy, defined as the lowest and least frequently administered dose of CpG DNA that mediated complete tumor rejection. We show that one priming dose of 15 nanomoles and one booster dose of 10 nanomoles of CpG DNA given 7 days apart, respectively, with lysate-loaded DCs were sufficient to mediate complete tumor rejection in vivo. This dose of CpG DNA was 42-fold higher than that required to activate DCs in vitro but was not associated with any toxicity in mice. Also, the cured mice rejected a subsequent challenge with fresh TS/A tumor, and both CD4(+) and CD8(+) T cells were required for tumor rejection. We conclude that effective DC-based therapy of a poorly immunogenic TS/A tumor is enhanced by optimized dosing of CpG DNA. Our data have important implications for DC-based clinical trials of breast cancer immunotherapy.

Biological therapy of breast cancer: recent clinical applications.

Advances have been made in breast cancer therapy, in both the adjuvant and metastatic settings. For example, in the adjuvant setting, genomic studies of breast cancer tissues have identified women with estrogen receptor-positive tumors who might not require chemotherapy, leading to the development of a diagnostic tool. There have also been significant developments with anticancer agents that target tumor cell surface receptors, such as HER2/neu, and those involved in angiogenesis and kinase-dependent pathways. New areas of research focus on the concept of breast cancer stem cells as well as the prognostic importance of bone marrow micrometastases in early-stage breast cancer. This review summarizes these advances in breast cancer clinical research.

Phase I trial of BAY 50-4798, an interleukin-2-specific agonist in advanced melanoma and renal cancer.

PURPOSE: BAY 50-4798 is an analogue of interleukin-2 that selectively activates T cells over natural killer cells. This phase I study was designed to determine the maximum tolerated dose (MTD) and safety of BAY 50-4798, screen for tumor response, and assess pharmacokinetics. EXPERIMENTAL DESIGN: Forty-five patients with metastatic melanoma or renal cancer were enrolled, 31 on escalating doses to determine the MTD, with 20 renal cell carcinoma patients treated at MTD to detect antitumor activity. BAY 50-4798 was delivered i.v. every 8 h, days 1 to 5 and 15 to 19, and could be repeated after 9 weeks if tumor was stable or responding. RESULTS: The MTD was defined by and reported in terms of doses received. The doses tested ranged from 1.3 to 26.1 microg/kg, and the MTD was defined as 10.4 microg/kg based on toxicities similar to those of aldesleukin. Two patients achieved partial responses, one with melanoma and one with renal cell carcinoma. Among all 45 patients, 53% and 9% experienced a grade 3 and 4 toxicity, respectively. Among the patients treated at the MTD of 10.4 microg/kg, 71% and 10% experienced a grade 3 and 4 toxicity, respectively. Pharmacokinetics showed dose-dependent peak concentrations (C(max)) and area under the curve with a half-life of approximately 2 h and no evidence of accumulation. Lymphocyte subset analysis confirmed the preferential expansion of T-cell subsets over natural killer cells. CONCLUSIONS: The antitumor activity of BAY 50-4798 in malignancies that respond to high-dose interleukin-2 was low. BAY 50-4798 might provide advantages over aldesleukin in antigen-specific immunotherapies.

Stereotactic radiosurgery for spinal metastases from renal cell carcinoma.

OBJECT: The role of stereotactic radiosurgery in treating renal cell carcinoma (RCC) metastases to the spine has previously been limited. In this study the authors evaluated the clinical outcome in patients with spinal RCC who underwent single-fraction radiosurgery. METHODS: Forty-eight patients with 60 RCC metastases to the spine (six cervical, 26 thoracic, 18 lumbar, and 10 sacral) were treated with a single-fraction radiosurgery technique and were followed for a period of 14 to 48 months (median 37 months). All patients were successfully treated in an outpatient setting. The tumor volume ranged from 5.5 to 203 cm3 (mean 61.9 cm3). Forty-two of the total 60 lesions had been previously treated with external-beam radiation therapy (EBRT). The maximum tumor dose was maintained at 17.5 to 25 Gy (mean 20 Gy). The volume of the spinal cord exposed to greater than 8 Gy ranged from 0.01 to 3 cm3 (mean 0.64 cm3); the volume of the spinal canal at the cauda equina level exposed to greater than 8 Gy ranged from 0.01 to 2.2 cm3 (mean 0.65 cm3). No radiation-induced toxicity occurred during the follow-up period. Axial and radicular pain improved in 34 (89%) of 38 patients who were treated primarily for pain. Tumor control was demonstrated in seven of eight patients treated primarily for radiographically documented tumor progression. In time six patients required open surgical intervention for tumor progression that had caused neurological dysfunction after radiosurgery. CONCLUSIONS: Spinal radiosurgery can be a successful therapeutic modality for the delivery of large-dose single-fraction radiation to RCC spinal metastases that are often poorly controlled with conventional EBRT modalities.

Long-term survivors after gamma knife radiosurgery for brain metastases.

BACKGROUND: Stereotactic radiosurgery, with or without whole-brain radiation therapy, has become a valued management choice for patients with brain metastases, although their median survival remains limited. In patients who receive successful extracranial cancer care, patients who have controlled intracranial disease are living longer. The authors evaluated all brain metastasis in patients who lived for > or = 4 years after radiosurgery to determine clinical and treatment patterns potentially responsible for their outcome. METHODS: Six hundred seventy-seven patients with brain metastases underwent 781 radiosurgery procedures between 1988 and 2000. Data from the entire series were reviewed; and, if patients had > or = 4 years of survival, then they were evaluated for information on brain and extracranial treatment, symptoms, imaging responses, need for further care, and management morbidity. These long-term survivors were compared with a cohort who lived for < 3 months after radiosurgery (n = 100 patients). RESULTS: Forty-four patients (6.5%) survived for > 4 years after radiosurgery (mean, 69 mos with 16 patients still alive). The mean age at radiosurgery was 53 years (maximum age, 72 yrs), and the median Karnofsky performance score (KPS) was 90. The lung (n = 15 patients), breast (n = 9 patients), kidney (n = 7 patients), and skin (melanoma; n = 6 patients) were the most frequent primary sites. Two or more organ sites outside the brain were involved in 18 patients (41%), the primary tumor plus lymph nodes were involved in 10 patients (23%), only the primary tumor was involved in 9 patients (20%), and only brain disease was involved in 7 patients (16%), indicating that extended survival was possible even in patients with multiorgan disease. Serial imaging of 133 tumors showed that 99 tumors were smaller (74%), 22 tumors were unchanged (17%), and 12 tumors were larger (9%). Four patients had a permanent neurologic deficit after brain tumor management, and six patients underwent a resection after radiosurgery. Compared with the patients who had limited survival (< 3 mos), long-term survivors had a higher initial KPS (P = 0.01), fewer brain metastases (P = 0.04), and less extracranial disease (P < 0.00005). CONCLUSIONS: Although the expected survival of patients with brain metastases may be limited, selected patients with effective intracranial and extracranial care for malignant disease can have prolonged, good-quality survival. The extent of extracranial disease at the time of radiosurgery was predictive of outcome, but this does not necessarily mean that patients cannot live for years if treatment is effective.

Evaluation of the OncoTCap (Oncology Thinking Cap) simulation in teaching medical students about clinical trials: some successes and some surprises.

OBJECTIVE: A training workshop for cancer clinical trials was developed utilizing a computer simulation encompassing cancer biology, metabolism, adverse effects, and clinical trial design. METHOD: Fourth-year medical students in a neoplasia elective course participated. The workshop was structured to maximize group discussions and interactions. Pretests and posttests were administered in a crossover design to evaluate learning about cancer clinical trials. Results. The comparison showed that the workshop did impart knowledge about cancer clinical trials. CONCLUSIONS: Student evaluations of the workshop showed slight improvements from the first year to the second year.

Enzyme-linked immunospot, cytokine flow cytometry, and tetramers in the detection of T-cell responses to a dendritic cell-based multipeptide vaccine in patients with melanoma.

A new generation of single-cell assays for measuring the frequency of peptide-specific T lymphocytes in cellular populations has become widely available. These assays, enzyme-linked immunospot (ELISPOT), cytokine flow cytometry, and tetramer binding, are used frequently for monitoring of cancer patient responses to vaccination therapies. We concomitantly used these three assays to determine the frequency of CD8(+) T cells in the circulation of 8 patients with metastatic melanoma who had received a multiepitope peptide/dendritic cell-based vaccine. Using peripheral blood mononuclear cells harvested before and a week after the last of four vaccines, we observed that the three assays detected a substantially different frequency of peptide-specific CD8(+) T cells. The tetramer assay consistently detected the highest numbers of peptide-specific CD8(+) T cells, followed by cytokine flow cytometry and then ELISPOT. There was no significant concordance among the assays in measuring the numbers of CD8(+) T cells specific for each of the peptides in the peripheral circulation of the patient. No significant pre- to postvaccine changes in the number of CD8(+) T cells specific for any of the peptides were observed. Thus, the dendritic cell-based vaccine was observed not to augment immune responses to the peptides in the patients. Because of a low frequency of the peptide-specific T cells in the peripheral circulation of the patients, these sensitive single-cell assays were used to measure values at the lower limit of detection. For this and other reasons, including the issues of tetramer specificity and ELISPOT sensitivity, caution in interpretation and serious attention to quality control are needed in monitoring of immune responses to anticancer vaccines.

Murine dendritic cell-induced tumor apoptosis is partially mediated by nitric oxide.

Dendritic cells (DC) are potent antigen-presenting cells that are important for the priming of antitumor cytotoxic T cells. Recent reports suggest that DC may also have direct cytotoxic effector functions against selected tumor-cell lines by mechanisms that are dependent on dendritic cell-tumor cell contact in vitro. The authors report that ex vivo-generated murine DC induce the apoptosis of a panel of syngeneic and allogeneic murine tumors. Apoptosis of the MCA205 fibrosarcoma tumor-cell line by C57BL/6-derived DC was not mediated by Fas/FasL interactions and, in contrast to other studies, DC-tumor cell contact was not required to effect tumor-cell killing by DC. Therefore, the authors postulated that tumor-cell killing was mediated by an apoptotic factor that was secreted by DC. Even though DC did not secrete such apoptotic cytokines as interferon-alpha or tumor necrosis factor-alpha, they did secrete nitric oxide, and tumor apoptosis was partially abrogated by the nitric oxide synthase antagonist NG-monomethyl-L-arginine. Therefore, the authors' data demonstrate a novel mechanism for DC-induced tumor-cell apoptosis that does not require DC-tumor cell contact and is partially mediated by nitric oxide.