One of the significant obstacles in the development of clinically relevant microarray-derived biomarkers and classifiers is tissue heterogeneity. Physical cell separation techniques, such as cell ...sorting and laser-capture microdissection, can enrich samples for cell types of interest, but are costly, labor intensive and can limit investigation of important interactions between different cell types.
We developed a new computational approach, called microarray microdissection with analysis of differences (MMAD), which performs microdissection in silico. Notably, MMAD (i) allows for simultaneous estimation of cell fractions and gene expression profiles of contributing cell types, (ii) adjusts for microarray normalization bias, (iii) uses the corrected Akaike information criterion during model optimization to minimize overfitting and (iv) provides mechanisms for comparing gene expression and cell fractions between samples in different classes. Computational microdissection of simulated and experimental tissue mixture datasets showed tight correlations between predicted and measured gene expression of pure tissues as well as tight correlations between reported and estimated cell fraction for each of the individual cell types. In simulation studies, MMAD showed superior ability to detect differentially expressed genes in mixed tissue samples when compared with standard metrics, including both significance analysis of microarrays and cell type-specific significance analysis of microarrays.
We have developed a new computational tool called MMAD, which is capable of performing robust tissue microdissection in silico, and which can improve the detection of differentially expressed genes. MMAD software as implemented in MATLAB is publically available for download at http://sourceforge.net/projects/mmad/.
Affinity-optimized T cell receptors can enhance the potency of adoptive T cell therapy. Afamitresgene autoleucel (afami-cel) is a human leukocyte antigen-restricted autologous T cell therapy ...targeting melanoma-associated antigen A4 (MAGE-A4), a cancer/testis antigen expressed at varying levels in multiple solid tumors. We conducted a multicenter, dose-escalation, phase 1 trial in patients with relapsed/refractory metastatic solid tumors expressing MAGE-A4, including synovial sarcoma (SS), ovarian cancer and head and neck cancer ( NCT03132922 ). The primary endpoint was safety, and the secondary efficacy endpoints included overall response rate (ORR) and duration of response. All patients (N = 38, nine tumor types) experienced Grade ≥3 hematologic toxicities; 55% of patients (90% Grade ≤2) experienced cytokine release syndrome. ORR (all partial response) was 24% (9/38), 7/16 (44%) for SS and 2/22 (9%) for all other cancers. Median duration of response was 25.6 weeks (95% confidence interval (CI): 12.286, not reached) and 28.1 weeks (95% CI: 12.286, not reached) overall and for SS, respectively. Exploratory analyses showed that afami-cel infiltrates tumors, has an interferon-γ-driven mechanism of action and triggers adaptive immune responses. In addition, afami-cel has an acceptable benefit-risk profile, with early and durable responses, especially in patients with metastatic SS. Although the small trial size limits conclusions that can be drawn, the results warrant further testing in larger studies.
Sarcomas constitute a heterogeneous group of tumors with different clinical behaviors and variable responses to systemic therapies. Recent immunotherapy studies with PD1 inhibitors (PD1i) show ...promising results with use in certain soft-tissue sarcomas; however, the clinical and molecular features that best predict response to PD1i remain unclear.
Demographic, imaging, histologic, and genetic sequencing data was collected for sarcoma patients who received nivolumab or pembrolizumab (PD1i) treatment at our institution between January 1st 2015 and April 23rd 2018. The primary objective was to determine progression-free survival (PFS) in patients with advanced sarcomas receiving PD1i. Secondary objectives included determining overall survival (OS) and assessment of characteristics associated with response to PD1i. Fifty-six patients who were treated with PD1i therapy met inclusion criteria for this study.
Partial response towards PD1i treatment was seen in 3 in 26 evaluable patients, but no complete responses were observed (overall response rate 11.5%). Within this group of patients, the 90 day PFS was found to be 48.8%. In patients in whom PD1 expression was known, there was a statistically significant positive correlation between expression of PD1 and longer PFS and OS rates. Patients that were treated with more than four cycles of PD1i therapy were also more likely to have a greater OS.
This study suggests activity of PD1i in a pretreated cohort of advanced sarcoma patients, particularly for the subset of patients with PD1 positive tumors. Our results highlight the importance of further research to better target the optimal patient population and markers of response.
We performed a phase 1 study to determine the maximum tolerable dose and safety of ipilimumab with stereotactic radiosurgery (SRS) or whole brain radiation therapy (WBRT) in patients with brain ...metastases from melanoma.
Based on the intracranial disease burden, patients underwent WBRT (arm A) or SRS (arm B). The ipilimumab starting dose was 3 mg/kg every 3 weeks, starting on day 3 of WBRT or 2 days after SRS. The ipilimumab dose was escalated to 10 mg/kg using a 2-stage, 3+3 design. The primary endpoint was to determine the maximum tolerable dose of ipilimumab combined with radiation therapy. The secondary endpoints were overall survival, intracranial and extracranial control, progression-free survival, and toxicity. The ClinicalTrials.gov registration number is NCT01703507.
The characteristics of the 16 patients enrolled between 2011 and 2014 were mean age, 60 years; median number of brain metastases, 2 (range 1->10); and number with EC disease, 13 (81%). Treatment included WBRT (n=5), SRS (n=11), and ipilimumab 3 mg/kg (n=7) or 10 mg/kg (n=9). The median follow-up was 8 months (arm A) and 10.5 months (arm B). A total of 21 grade 1 to 2 neurotoxic effects occurred, with no dose-limiting toxicities. One patient experienced grade 3 neurotoxicity before ipilimumab administration. Ten additional grade 3 toxicities were reported, with gastrointestinal toxicities (n=5; 31%) the most common. No patient developed grade 4 or 5 toxicity. The median progression-free survival and overall survival in arm A was 2.5 months and 8 months and in arm B was 2.1 months and not reached, respectively.
Concurrent ipilimumab 10 mg/kg with SRS is safe. The WBRT arm was closed early because of slow accrual but demonstrated safety with ipilimumab 3 mg/kg. No patient experienced dose-limiting toxicity. Larger studies, including those with combination checkpoint inhibitor therapy and SRS, are warranted.
Capillary leak syndrome is a rare life-threatening disorder of acute endothelial hyperpermeability. It consists of initial fluid extravasation resulting in hypotension, hypoalbuminemia, and ...hemoconcentration, followed by noncardiogenic pulmonary edema from rapid fluid remobilization into intravascular compartment. Drug-induced etiology is an important diagnostic consideration in cancer patients, particularly with use of antimetabolites, immunostimulants, and monoclonal antibodies. Sorafenib-mediated capillary leak syndrome has never been reported. Here, we present the case of a 29-year-old female patient with a desmoid tumor of the thigh, who was admitted for acute hypoxic respiratory failure after recent initiation of sorafenib. She was found to have extensive pulmonary edema, bilateral pleural effusions, and hemoconcentration, all of which stabilized on supportive care with noninvasive mechanical ventilation and intravenous diuresis. Her infectious and cardiac work-up were negative. Given the temporal relationship between sorafenib use and symptom onset as well as a lack of an alternative etiology of her findings, patient was deemed to have sorafenib-induced acute capillary leak syndrome. Importantly, she did not become hypotensive prior to or during this hospitalization. To our knowledge, we reported for the first time an atypical presentation of acute capillary leak syndrome due to sorafenib use without hemodynamic instability.
Vascular endothelial growth factor (VEGF) contributes to blood-retinal barrier (BRB) dysfunction in several blinding eye diseases, including diabetic retinopathy. Signaling via the secreted protein ...norrin through the frizzled class receptor 4 (FZD4)/LDL receptor–related protein 5–6 (LRP5–6)/tetraspanin 12 (TSPAN12) receptor complex is required for developmental vascularization and BRB formation. Here, we tested the hypothesis that norrin restores BRB properties after VEGF-induced vascular permeability in diabetic rats or in animals intravitreally injected with cytokines. Intravitreal co-injection of norrin with VEGF completely ablated VEGF-induced BRB permeability to Evans Blue-albumin. Likewise, 5-month diabetic rats exhibited increased permeability of FITC-albumin, and a single norrin injection restored BRB properties. These results were corroborated in vitro, where co-stimulation of norrin with VEGF or stimulation of norrin after VEGF exposure restored barrier properties, indicated by electrical resistance or 70-kDa RITC-dextran permeability in primary endothelial cell culture. Interestingly, VEGF promoted norrin signaling by increasing the FZD4 co-receptor TSPAN12 at cell membranes in an MAPK/ERK kinase (MEK)/ERK-dependent manner. Norrin signaling through β-catenin was required for BRB restoration, but glycogen synthase kinase 3 α/β (GSK-3α/β) inhibition did not restore BRB properties. Moreover, levels of the tight junction protein claudin-5 were increased with norrin and VEGF or with VEGF alone, but both norrin and VEGF were required for enriched claudin-5 localization at the tight junction. These results suggest that VEGF simultaneously induces vascular permeability and promotes responsiveness to norrin. Norrin, in turn, restores tight junction complex organization and BRB properties in a β-catenin–dependent manner.
Background
Retroperitoneal liposarcomas are locally aggressive and frequently recur following complete surgical resection. Palbociclib, a cyclin-dependent kinase (CDK) 4/CDK6 inhibitor, is effective ...in the treatment of metastatic or unresectable liposarcoma.
Objective
The purpose of this study was to describe our initial experience using adjuvant palbociclib to delay recurrence.
Methods
Patients with resected RPS were identified from a prospectively maintained institutional database. In 2017, we began offering adjuvant palbociclib to patients following complete gross resection. Treatment interval, defined as the time between surgical resection and re-resection or change in systemic therapy, was compared between patients selected for adjuvant palbociclib or observation.
Results
Between 2017 and 2020, 12 patients underwent a total of 14 operations (14 patient cases) and were selected for adjuvant palbociclib for recurrence prevention. These patients were compared with 14 patients who, since 2010, underwent a total of 20 operations (20 patient cases) and were selected for observation. Histology was primarily dedifferentiated liposarcoma for both groups (observation: 70% 14/20; adjuvant palbociclib: 64% 9/14). All patients underwent complete gross resection. Neither age, number of previous surgeries, histologic grade, or Eastern Cooperative Oncology Group (ECOG) performance status differed between groups (
p
> 0.05 for all). Patients selected for adjuvant palbociclib experienced a longer treatment interval than those selected for observation, although it did not reach statistical significance (20.5 months vs. 13.1 months,
p
= 0.08, log rank).
Conclusion
Adjuvant palbociclib may be associated with a prolonged interval between liposarcoma resection and the need for re-resection or other systemic therapy. Palbociclib may be effective in delaying liposarcoma recurrence, and its use for this indication warrants prospective study.
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