bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a novel T-cell immunotherapy targeting HEATR1.
Authors: Dossa Robson Grando , Cunningham Tanya , Bleakley Marie
Published: November 2019

149

Background: Allogeneic hematopoietic stem cell transplantation (HCT) often cures acute leukemia. However leukemic relapse remains a major cause of HCT failure, and patients with post-HCT relapse have a very poor prognosis. We are developing T cell immunotherapies targeting leukemia-associated minor histocompatibility (H) antigens to manage post-HCT relapse. Because the presentation of minor H antigens is HLA-restricted, a panel of hematopoietic-restricted, leukemia-associated minor H antigens is required to enable the development of broadly applicable minor H antigen targeted immunotherapy. We previously discovered a HLA- B*0801-restricted, leukemia-associated minor H antigen, HEATR1. We showed that HEATR1-specific T cells can specifically kill leukemic blasts and prevent engraftment in a murine model, implying that this minor H antigen is expressed in leukemic stem cells. We have now developed immunotherapy targeting HEATR1 using genetically modified T cells. Methods: We isolated a HEATR1-specific T cell clone from the peripheral blood of a normal donor and sequenced its T cell receptor (TCR). The TCR was codon-optimized and cysteine-modified to maximize expression in T cells and reduce the risk of mispairing with endogenous TCR chains, then cloned into a multicistronic lentiviral vector (LV). Primary CD8+T cells were transduced with the HEATR1 TCR LV and evaluated with a range of assays. Results: The HEATR1-specific T cell clone specifically killed B8+ HEATR1+ primary leukemia. Similarly, CD8+ HEATR1 TCR-transduced T cells killed target cells pulsed with HEATR1 peptide (ISKERAEAL), but not the allelic variant control peptide (ISKERAGAL), and specifically killed cell lines that endogenously present the HEATR1 minor H antigen. HEATR1-transduced T cells also secrete cytokines and proliferate in response to HEATR1+ but not HEATR1-cells. Conclusions: We have demonstrated that HEATR1-specific T cell clone and HEATR1 TCR-transduced T cells can kill HEATR1+ cells. If the safety and efficacy of HEATR1 TCR immunotherapy is confirmed in further preclinical studies, development of phase I clinical studies will be warranted and may ultimately provide a new option for management of relapse after HCT.
Development of human NKG2D-CD3ε chimeric antigen receptor (CAR) for T-cell-mediated cancer immunotherapy.
Authors: Kusmartsev Sergei , Vieweg Johaness , Prima Victor
Published: November 2019

150

Background: NKG2D is a lectin-like type 2 transmembrane receptor that expressed by natural killer cells and some T cell subsets. Stimulation of NKG2D receptor with specific agonistic ligands produces activating signals through signaling adaptor protein DAP10 leading to the enhanced cytokine production, proliferation, and cytotoxicity against tumor cells. There is strong evidence that NKG2D ligands are expressed in many human tumors, including melanoma, leukemia, myeloma, glioma, and carcinomas of the prostate, breast, lung, and colon. Recent studies also demonstrated that T cells bearing chimeric antigen receptor (CAR) NKG2D linked to CD3ζ (zeta) chain produce marked in vitro and in vivo anti-tumor effects. The aim of current study was to determine whether human T cells bearing chimeric antigen receptor (CAR) NKGD2 linked to CD3ε (epsilon) chain could be activated by the NKG2D-specific stimulation and able to kill human cancer cells. Given the important role of CD3ε in activation and survival of T cells, we hypothesized that NKG2D-CDε-bearing T cells could exert strong in vitro and in vivo anti-tumor effects. Methods: NKG2D CAR was produced by linking human NKG2D to DAP10 and the cytoplasmic portion of the CD3ε chain. Original full-length human cDNA clones were obtained from NIH Mammalian Gene Collection (MGC). Functional domain analysis and oligonucleotide design in the in-Fusion system of DNA cloning (Clontech) was used to generate the retroviral expression constructs. Results: Human PBMC-derived T cells were retrovirally transduced with newly generated NKG2D-CD3ε CAR DNA construct. These NKG2D CAR-expressing human T cells responded to NKG2D-specific activation by producing IFN-γ and exhibited significant cellular cytotoxicity against human tumor cells in vitro. In vivo studies demonstrated that NKG2D-CD3ε-bearing cells are capable of inhibiting growth of DU-145 human prostate cancer in the immunodeficient mice. Conclusions: Collectively, our data indicate the feasibility of developing chimeric antigen receptor NKG2D-CD3ε for T cells and suggest that adoptive transfer of T cells bearing NKG2D-CD3ε CAR could be potentially effective for immunotherapy of cancer patients.
Combinatorial IL13Rα2 chimeric antigen receptor-T cells plus checkpoint blockade to treat solid tumors in murine and canine models.
Authors: Yin Yibo , Boesteanu Alina , Xu Chong , Posey Avery , Cook Danielle , Blouch Kristin , McGettigan-Croce Bevin , Mason Nicola , June Carl H. , Lin Zhiguo , Johnson Laura A.
Published: November 2019

152

Background: Glioblastoma (GBM) is a deadly cancer, with a 5-year survival rate of less than 10%. T cells can be redirected to kill cancer cells using chimeric antigen receptors (CAR), a promising method to treat solid tumors. IL13Rα2 is expressed in many solid tumors but not normal tissues, and provides a target for CAR T cells as a powerful immunotherapy treatment. Methods: Human and canine tumors were screened for IL13Rα2 expression by flow cytometry and RT-PCR. Different IL13Rα2 single-chain variable fragments (scFv) were tested in CARs in vitro against human and canine recombinant IL13Rα2 protein to identify a cross-reactive clone. IL13Rα2 CARs expressed in human and canine T cells and showed antigen-specific stimulation by cytokine secretion and target cell lysis. Solid tumors were used to establish in vivo subcutaneous and orthotopic xenograft models in NSG mice. Mice received a single treatment of 2-5 million CAR T cells IV with or without anti PD-1, CTLA-4 or TIM3 mAb checkpoint blockade. Results: IL13Rα2 was detected on three human GBM (D270, U251 and U87), four canine osteosarcomas (BW-, CS-, MC- and SK-KOSA) and two canine lung cancer cell lines (Cacal3, Cacal5). Two different IL13Rα2 CAR were generated that recognized human IL13Rα2 and not IL13Rα1, one also recognized canine IL13Rα2. Five million IL13Rα2 CAR T-cells delivered IV were able to eliminate established GBM tumors. Use of fewer CAR T cells initially controlled tumor growth, followed by tumor outgrowth correlated with expression of T cell exhaustion markers. Combined treatment with CARs plus checkpoint blockade mAb delivered IP had synergistic effects, restoring anergic T-cell function and improving tumor treatment. Conclusions: IL13Rα2 is highly expressed on human and canine tumors, but not normal tissues. IL13Rα2 specific CAR T cells successfully respond to human and canine tumors and treat GBM in a xenograft mouse model, although this effect was transient at lower treatment doses. Addition of checkpoint blockade mAbs to CAR therapy was beneficial for the treatment of solid tumors. We plan to utilize this treatment in a canine spontaneous cancer preclinical model and translate into clinical trials for patients with GBM.
MVA-5T4 immunotherapy and low-dose cyclophosphamide for advanced colorectal cancer (TaCTiCC): An open-label, randomized phase I/II trial.
Authors: Scurr Martin , Pembroke Tom , Adams Richard , Blount Daniel , Brewster Alison , Gwynne Sarah , Harrop Richard , Jones Robert , Hills Robert , Gallimore Awen , Godkin Andrew
Published: November 2019

154

Background: Current immunotherapies including checkpoint inhibitors and vaccines for advanced colorectal cancer (CRC) have been largely ineffective. We hypothesized that combining an MVA-based vaccine targeting the tumor-associated antigen 5T4 (TroVax) with low-dose cyclophosphamide to deplete Foxp3+regulatory T-cells (Tregs), could improve immunological responses and patient outcomes. Methods: In this open-label phase I/II clinical trial, TaCTiCC (TroVax and Cyclophosphamide Treatment in Colorectal Cancer) 53 patients with inoperable metastatic CRC were randomized to receive either no treatment (group 1, n=8), metronomic low-dose CPM (50mg B.D. during treatment weeks 1&3; group 2, n=9), TroVax only (6 i.m. injections weeks 4 to 16, group 3, n=18), or low-dose CPM followed by TroVax (group 4, n=18). The primary endpoint was boosted anti-5T4 responses at week 7, as measured by increased T-cell and antibody responses; secondary endpoints included progression-free (PFS)/overall survival (OS), and anti-5T4 responses over the trial period. Results: CPM depleted Tregs in 21/27 patients during treatment week 3 (p=0.0045), resulting in significantly prolonged PFS amongst groups 2&4 over group 1 (5.0 vs. 2.5 months, HR=0.17 95% CI 0.048-0.62, p=0.0072). TroVax induced a >2-fold increase in anti-5T4 immune responses in 15/36 group 3&4 patients; these patients experienced significantly prolonged median PFS (6.5 vs. 2.4 months, HR 0.31 95% CI 0.14-0.65, p=0.0022) and OS (20 vs. 12 months, HR=0.37 95% CI 0.17-0.82, p=0.014). Combination of CPM & TroVax was not significantly superior. The primary endpoint at a single timepoint was not met since CPM-induced responses declined by week 7, and TroVax-induced responses were greatest at weeks 10-16. No serious adverse events were reported. Conclusions: Both CPM and TroVax induced highly beneficial anti-tumor immune responses resulting in significantly prolonged survival of end-stage CRC patients without toxicity. This is the first study to show a clear benefit of immunotherapy in advanced CRC, and suggests this approach may be superior (and less toxic) to continuous palliative chemotherapy in these patients. Clinical trial information: 54669986.
A novel cancer vaccine platform utilizing autologous tumor lysate loaded into capped yeast cell wall particles.
Authors: Peace Kaitlin M. , Vreeland Timothy J , Hale Diane F , Jackson Doreen O , Greene Julia M , Trappey Alfred F , Berry John S , Clifton Guy T , Herbert Garth S , Yu George , Wagner Tom , Peoples George Earl
Published: November 2019

169

Background: Our current tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine employs yeast cell wall particles (YCWP) to deliver antigen to DC ex vivo and is being tested in a randomized phase IIb trial. This strategy may be improved by injecting TL-loaded YCWP as an intradermal vaccine, with in vivo DC uptake. Silicate capping should allow YCWP to retain TL longer and stimulate DC uptake. Here, we present preclinical data on the tumor lysate, particle only (TLPO) vaccine concept vs. TLPLDC. Methods: To test the TLPO concept, YCWP were loaded with fluorescence (flr) labeled albumin and capped (cp) vs. uncapped (ucp) particles were compared for flr leak. Next, YCWP were added to cultured macrophages to evaluate DC uptake. Cells were then lysed, centrifuged, and flr in the cytoplasm vs. organelles measured. 3 C57B mice were then injected with 100ml NaCl, 106empty cp YCWP, or 1mcg GM-CSF. 5 hours (hr) post-injection, 100ml NaCl was injected into the same site, withdrawn, and examined via microscope to count monocytes. TLPO was compared to TLPLDC in a B16 murine melanoma survival model. Finally, 4 grey horses with equine melanoma were treated with autologous TLPO, injected biweekly for 4 vaccinations. Target lesions were assessed over 6 months. Results: Compared to ucp YCWP, cp had decreased flr leak at 1 (15.8% vs. 24.7%) and 2 hr (6.7% vs. 16.6%), increased uptake by DC (2hr flr readings 11065 vs. 3928) and higher delivery to DC cytoplasm (68.9% vs. 48.8%). Empty cp YCWP showed increased recruitment of monocytes (276/hpf) vs. GM-CSF (55/hpf) or NaCl alone (18/hpf). In the B16 murine melanoma model, the median survival time in days was 21 for controls (n=5), 42 for TLPLDC (n=10), and 56 for TLPO (n=20). At 6 months, the equine model revealed 1 complete and 3 partial responses (50%, 68%, and 45% tumor reduction). Conclusions: Silicate capping of the YCWP effectively limits leakage of contents, improves uptake by DC and delivery to the cytoplasm without the need for GM-CSF. In early animal studies, TLPO appears to have equivalent efficacy to TLPLDC, but eliminates the need for in vitro DC loading. We plan to perform a bridging study comparing TLPO to TLPLDC after enrollment is complete in our phase IIb TLPLDC melanoma trial.
Identification of somatic mutations and neoantigens to predict development of autoimmune adverse events to immune therapy in melanoma.
Authors: Wells Keith Ryan , Amato Carol M , Hintzsche Jennifer , Robinson William
Published: November 2019

19

Background: Immunotherapy has quickly altered the treatment paradigm for advanced melanoma. Prior studies using whole exome sequencing (WES) in immunotherapy have shown limited correlation with clinical response to immunotherapy, but not an evaluation of autoimmune side effects. Understanding mechanisms of immune-related adverse events (irAE) at a genomic level may lead to improved rational treatment design and better patient selection. Methods: DNA was extracted from 87 tumor samples from 49 patients with metastatic melanoma treated with ipilimumab (anti-CTLA-4) or with nivolumab or pembrolizumab (anti-PD-1) immunotherapy. WES was performed with exome capture on an Illumina HiSeq sequencer. Statistical analysis was performed with Chi-squared testing. Computational neoantigen analysis has been performed on the sequencing data. Results: 27 patients with advanced or metastatic melanoma were treated with only ipilimumab, 11 with only anti-PD1, and 11 patients were treated with both anti-CLTA-4 and anti-PD1 either sequentially or in combination. irAE evaluated included cutaneous, colitis, endocrinopathies, hepatitis, and pneumonitis. In 10 patients who developed colitis, 14 mutated genes were enriched in their tumor samples (p=0.01-0.046) compared with patients without colitis. Analyzing all patients with any irAE versus no irAE treated with anti-CTLA-4, anti-PD1, or both (either sequential or combination) revealed 7 mutated genes enriched in patient samples who developed irAE (p=0.02-0.05). Preliminary neoantigen analysis has identified possible irAE associated neoantigens and further analysis of additional samples are ongoing. Overall mutational burden of the tumor samples did not correlate with development of irAE. Conclusions: Autoimmune side effects are frequent and often serious side effects of immunotherapy for melanoma. Genetic analysis may provide insight in prediction of these side effects and help direct therapeutic decisions.
Development of DDPCR blood-based diagnostic tests that simultaneously measure mRNA expression from immune and cancer cells.
Authors: Mellert Hestia S. , Jackson Leisa , Tompkins Chris , Lodge Anne , Pestano Gary Anthony
Published: November 2019

22

Background: Therapeutic options for patients with non-small cell lung cancer (NSCLC) continue to expand with the advent of immunotherapies. Lack of tissue and drawbacks with available IHC tests have increased the need for blood-based diagnostics. Thus, the detection of circulating nucleic acids has become highly relevant to clinical testing. Methods: We focused on extending the utility of blood-based testing for measurement of intra-cellular transcripts to multiplexed detection of gene expression. Specifically, we addressed maximizing the yield of quality circulating RNA for use in multiplexed droplet digital PCR (ddPCR) assays. Evaluation criteria included droplet counts for biomarkers of cancer and immunotherapy response. The markers evaluated were CD45, CD3, CK8, CK18, CK19, and PD-L1. Specimens included cell lines and prospectively collected samples from normal, healthy donors and donors with NSCLC. Results: Cell lines expressing variable levels of cytokeratins and PD-L1 were used to establish assay sensitivity. In these experiments, the test system could detect these markers in the equivalent of a single cell. We evaluated specificity using RNA from these same cell lines, resting and activated lymphocytes, and monocytes. With the exception of CK8, all assays demonstrated the expected specificities. Given the complexity of assessing PD-L1 in circulation because of its expression on immune cells, a threshold of 30 copies of PD-L1 was established using normal healthy donors (n = 9). Using this cut-off we then measured PD-L1 in circulating RNA from donors with NSCLC (n = 20). By these criteria, PD-L1 expression of sufficient copy number was restricted to a single EGFR wild-type donor (1/10). Previous reports have indicated that for EGFR wild-type patients, PD-L1 over expression may be considered a poor prognostic indicator of OS. Conclusions: We are developing sensitive and specific methods that can be applied to gene expression studies in blood. We have shown feasibility of these methods by evaluating key immune and cancer-specific RNAs. Evaluations are on-going with prospective sample collections to validate thresholds for this assay that may lead to its clinical utility.
Identifying treatment options for triple negative breast cancer patients using RNA-sequencing.
Authors: Pedersen Gitte
Published: November 2019

31

Background: In the context of diagnostics, RNA is proxy for proteins and proteins are typically targets for drugs; e.g. breast cancer is typically driven by over-expression of various hormone receptors and Her2. In the current standard-of-care setting there is no measurement of mutations. Furthermore, all the markers for response to the new immune therapies are expressed as mRNA. Approximately 15% of the breast cancer patients are triple negative. Due to the poor outcome of chemo, standard-of-care guidelines (NCCN) suggests doctors encourage the patient to enroll in clinical trials. However, with more than 2000 ongoing trials in breast, which trial could potentially benefit the patient? Methods: Using the RNA-seq data from the TCGA study, we analyzed more than 120 triple negative datasets. Results: We found at least one over-expressed checkpoint inhibitor target in almost all the patients, suggesting that if you analyzed for all of the checkpoint targets, it would be possible to find a clinical study for these patients. Furthermore, when we analyzed over-expressed tumor antigens, we realized that it would be possible to design sophisticated combination trials with this information. In addition, we identified patients that were BRCAwt with an impaired DNA repair pathway; e.g. some had BRCA silencing and could potentially benefit from PARP inhibitors. Finally, a small number of patients overexpressed the androgen receptor for which there is a drug approved for prostate cancer. Conclusions: Compared to DNA analysis, tumor RNA profiling has the potential to guide a much broader set of drugs and treatment approaches including immunotherapy and chemotherapy. Messenger RNA (mRNA) analysis can reveal tumor antigens and drug targets expressed by cancer cells, as well as the vital status of the tumor microenvironment including immune response, the integrity of DNA repair mechanisms, and the engagement of angiogenesis and other cancer-related pathways.
Prevalence and clinical implications of T-cell immunoglobulin mucin type-1 (TIM-1) in multiple tumor types.
Authors: Halim Abdel , Bagley Rebecca G. , Turner Christopher D. , Keler Tibor
Published: November 2019

34

Background: TIM-1 (KIM-1, HAVcr-1) is a type 1 transmembrane glycoprotein. Expression is limited in healthy tissues but upregulated after kidney injury, in ovarian cancer and renal cell carcinoma (RCC). TIM-1 is associated with a more malignant RCC phenotype and immune response regulation. CDX-014, an antibody drug conjugate, contains a fully human IgG1 monoclonal antibody (mAb) conjugated to the potent cytotoxin MMAE. CDX-014 is in a Ph 1/2 trial for RCC (NCT02837991). The prevalence of TIM-1 in other cancers was investigated to explore the broader potential for CDX-014. Methods: Tumors and normal adjacent tissues (NAT) were provided (Mosaic Labs) via IRB-reviewed protocol MOS001 for in vitro analysis of remnant, anonymized human samples. The study included 188 tumors: 30 renal, 45 ovarian, 34 endometrial, 2 cervical, 2 vaginal, 15 bile duct, 15 CRC, 30 NSCLC and 15 thymoma plus 75 NAT. Mosaic performed a validated immunohistochemistry assay on FFPE tissues. A FITC-conjugated, anti-TIM-1 mAb was applied after slide deparaffinization and antigen retrieval. Anti-FITC (Novus Bio), Envision+ HRP and DAB (Dako) were used for visualization. A pathologist scored hematoxylin-counterstained slides for % positive cells and staining intensity. A cut-off of > 2% of cells staining at any intensity was deemed positive. Results: TIM-1 was universally prevalent in renal papillary (14/14) and clear cell carcinoma (CCC [13/13]) plus vaginal CCC (2/2). TIM-1 was also seen in ovarian CCC (12/15; 80%), endometrial CCC (9/21; 43%), adeno NSCLC (2/15; 13%), serous ovarian (1/10; 10%), adeno endometrial (1/13; 8%) and CRC (1/15; 7%). There was no staining in chromophobe RCC (3/3), cervical CCC, endometrioid or mucinous ovarian (10 each), bile duct carcinoma, squamous NSCLC or thymoma. There was minimal to no TIM-1 in NAT except for 7/10 kidney samples (possibly from unappreciated kidney injury). Conclusions: The data suggest that in addition to renal and ovarian cancer, TIM-1 targeted therapy such as CDX-014 warrants exploration in patients with endometrial CCC, vaginal CCC and adeno NCSLC. These results support the ongoing first in human Ph 1/2 study in RCC and potential broader clinical development of CDX-014 in other indications.
Mutation burden as a biomarker of response to immune checkpoint therapy in nine solid cancers.
Authors: Ganesan Shridar , Bhanot Gyan , Mehnert Janice M. , Silk Ann W. , Ross Jeffrey S. , Pavlick Dean , Ali Siraj Mahamed , Markowski Paul , Kaufman Howard L. , Sullivan Ryan J. , Lovly Christine Marie , Sosman Jeffrey Alan , Johnson Douglas Buckner , Betigeri Anil , Subramanian Kalyanasundaram , Panda Anshuman
Published: November 2019

35

Background: A high mutation burden a biomarker of response to immune checkpoint therapy in melanoma, non-small cell lung cancer, and colorectal cancer. It is unknown whether mutation burden is predictive of response in other cancer types, and whether it is identifiable using available clinical assays. Methods: Using data for 10,745 tumors from 33 solid cancer types in TCGA, we looked for a mutation burden threshold (iCAM) in each cancer type associated with gene expression signatures of a blocked immune response of robust CD8+T cell response and up-regulation of immune checkpoint genes. Results: A unique iCAM threshold was identified in nine cancers: melanoma and lung, colon, endometrial, and gastric adenocarcinoma; serous ovarian, bladder urothelial, cervical, and ER+ HER2− breast cancer. iCAM thresholds applied to published clinical data for patients treated with immune checkpoint therapy showed that iCAM+ patients had significantly better response. iCAM+ tumors can be identified from clinical-grade NGS assays with high accuracy . In a prospective melanoma cohort of patients treated with anti- PD-1 patients with iCAM+ tumors had significantly better objective response rates, progression free survival, and overall survival compared patients to iCAM− tumors. Pattern of somatic mutations were different in iCAM+ and iCAM− tumors, suggesting different mechanism of carcinogenesis in iCAM+ versus iCAM− tumors. Higher fractions of leukocytes were NK (Natural Killer) cells and macrophages were M1 polarized, and a lower fraction of T cells were regulatory T cells in iCAM+ tumors compared to iCAM− tumors. Over 75% of the genes significantly up-regulated in iCAM+ tumors in every cancer types were in the immune response pathway, confirming immune response to be the main differentiator in iCAM+ veruss iCAM− tumors. Conclusions: In nine cancer types, a clinically useful mutation burden threshold (iCAM) associated with gene expression signatures of blocked immune response can identify likely responders to immune checkpoint therapy, and iCAM status is identifiable using currently available clinical NGS assays.
Blood-based predictive biomarkers for overall survival (OS) in patients (pts) receiving the immunotherapy sipuleucel-T (sip-T).
Authors: Oh William K. , Kandadi Harini , Sheikh Nadeem Anwar , Galsky Matt D.
Published: November 2019

36

Background: Sip-T is an FDA-approved immunotherapy for the treatment of asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC). While baseline prostate-specific antigen level correlates with prolonged OS in pts treated with sip-T, biomarkers predictive of OS remain elusive. Gene expression signatures in peripheral blood (PB) correlate with prognosis in mCRPC (Ross et al, Lancet Oncol. 2012). This study sought to identify a candidate PB gene signature predictive of OS benefit with sip-T. Methods: PB mononuclear cells from sip-T or control (CN) mCRPC pts in the IMPACT trial (NCT00065442) were collected prior to leukapheresis. Affymetrix gene chip (HGU133P2) screening evaluated gene expression; association of gene expression with OS was performed using a multivariate Cox proportional hazards regression model, where OS was fit to gene expression and the 2003 baseline Halabi prognostic variables. The top 50 gene candidates were selected for qPCR confirmation. Results: Out of the 50 gene candidates selected for qPCR confirmation, 5 genes were associated with OS. High expression of SNTB1 and CHI3L2 and low expression of SYNGR3, AURKC, and ZNF268 were associated with improved OS in sip-T–treated pts but not in CN arm pts. A composite gene score (CGS) was calculated incorporating expression of these genes. In a CGS tertile analysis, OS in the top and middle sip-T tertiles was significantly better compared with the corresponding CN groups (Table). The lowest sip-T tertile had a median OS similar to that of the CN arm. Conclusions: CGS based on baseline gene expression may predict OS outcomes for mCRPC pts receiving sip-T. Compared with the CN arm, OS was significantly improved in the top two tertiles of sip-T–treated pts; OS in the bottom tertile was similar to the CN arm. Clinical trial information: NCT00065442. [Table: see text]
Tumor mutational load in gynecological and breast cancer.
Authors: Lynce Filipa , Xiu Joanne , Obeid Elias , Tan Antoinette R. , Gatalica Zoran , Isaacs Claudine , Pohlmann Paula Raffin
Published: November 2019

44

Background: Lack of test standardization and conflicting results on PD1 and PD-L1 immunohistochemistry (IHC) assays challenge their use as predictive biomarkers for checkpoint inhibitors. High tumor mutational load (TML) has been linked to therapeutic response with immune checkpoint inhibition in melanoma, lung and colorectal cancer. Herein, we explore association of TML and PD1/PD-L1 expression in gynecological (GC) and breast cancer (BC). As secondary aim we explore the association of TML with BRCA1/2 mutations. Methods: De-identified data from molecular profiling on GC and BC tumors from the CARIS Life Sciences database was analyzed after obtaining IRB approval. TML was defined as the total number of nonsynonymous, somatic mutations per Mb sequenced with a 592-gene panel. PD-1 IHC was tested on Tumor Infiltrating Lymphocytes (TIL) with the cutoff of 1/HPF; PD-L1 expression was measured on tumor cells with the cutoff of 2+, 5%. Biomarker association was tested with ANOVA test (SPSS v23, IBM). Results: As shown in table, cervical (CC) and endometrial cancers (EC) had the highest TML and squamous CC and triple negative BC (TNBC) tumors with highest PD-L1. In EC, MSI-H was associated with higher TML when compared to MSS (20.1 vs. 6.1, p<0.001); 4 POLE-mutated tumors all carried TML (36-678) higher than mean (11.5). TML was not associated with PD1 or PDL1 positivity in any of the diseases. BRCA1/2 mutations were associated with higher mean TML in ovarian cancer (OC) (6.8 vs. 5.4 in wild type, p<0.001) but not in BC (6.3 vs. 6.8 in wild type, p=0.48). Conclusions: In this sample of patients who underwent molecular profiling, there was no association between TML and PD1 or PD-L1 expression. Association between BRCA1/2 tumor mutations and TML in OC is worth exploring. High TML in CC and EC support the development of immunotherapy for these diseases. [Table: see text]
Characterization of potential predictive biomarkers of response to nivolumab in CheckMate-141 in patients with squamous cell carcinoma of the head and neck (SCCHN).
Authors: Ferris Robert L. , Concha-Benavente Fernando , Blumenschein George R. , Harrington Kevin J. , Fayette Jerome , Colevas A. Dimitrios , Licitra Lisa F. , Kasper Stefan , Even Caroline , Gillison Maura L. , Worden Francis , Saba Nabil F. , Haddad Robert I. , Tahara Makoto , Hasegawa Yasuhisa , Yen Chia-Jui , Lynch Mark John , Monga Manish , Geese William J. , Vokes Everett E.
Published: November 2019

5

Background: Nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody, demonstrated longer median overall survival (7.5 vs. 5.1 months) and improved response (13.3% vs. 5.8%) versus investigator choice chemotherapy (ICC) in patients with recurrent SCCHN after platinum failure in CheckMate 141 (NCT02105636), a randomized, open-label Phase 3 trial. We screened peripheral blood lymphocytes (PBL) to identify biomarkers which may predict response to nivolumab. Methods: Paired baseline (day 1) and on treatment (day 43) PBL samples (n=36; 24 nivolumab; 12 ICC) were analyzed using multicolor flow cytometry and a non-competing anti-PD-1 antibody. Results were correlated with clinical outcome: responders (complete/partial response) and non-responders (stable or progressive disease). Results: Levels of CD8+ T cells at baseline and on treatment were higher in nivolumab responders compared to non-responders (23% vs. 13%; p<0.05). Interestingly, PD-1+ CD8+ and PD-1+ CTLA-4+ CD8+ effector T cells (likely exhausted T cells) decreased about 2-fold following nivolumab in both responders and non-responders (p<0.05), whereas, the decrease in CTLA-4+ CD8+ effector T cells following nivolumab was significant in responders only (8% vs. 5%; p<0.05). Levels of PD-1+ TIM-3+ CD8+ effector cells decreased following nivolumab in non-responders only (11% vs. 7%; p<0.05), a similar non-significant reduction was observed in responders. Levels of PD-1+Tregs were lower in responders than non-responders at baseline (19% vs. 33%; p<0.01), and following nivolumab (12% vs. 20%; p<0.001). As in T effector cell populations, PD-1+ Tregs decreased about 1.6-fold after nivolumab in both responders and non-responders (p<0.01). Interestingly, baseline Ki67+ Treg levels were lower in non-responders (28% vs. 17%; p<0.05). Conclusions: Response to nivolumab may be associated with higher levels of CD8+ T cells and CTLA-4+ CD8+ effector T cells, and lower PD-1+ CD8+ effector T cells and PD-1+ Tregs at baseline. Targeting both PD-1 and CTLA-4 axes is warranted in SCCHN to overcome suppressive signals in CD8+ effector T cells and in Treg cells expressing both checkpoint receptors. Clinical trial information: NCT02105636.
Feasibility of miR-9, miR-21, and miR-155 as alternative biomarkers in both HPV-positive and HPV-negative cervical cancers.
Authors: Chung Dawn , Park Sunyoung , Eom Kiyoon , Park Kwang Hwa , Lee Hyeyoung
Published: November 2019

52

Background: Cervical cancer is the second leading cause of death among female patients with cancer in the world. High risk human papillomavirus has causal roles in cervical cancer initiation and progression by deregulating several cellular processes. However, HPV infection is not sufficient for cervical carcinoma development. Therefore, other genetic and epigenetic factors may be involved in this complex disease, and the identification of which may lead to better diagnosis and treatment. Our aim was to analyze the expression of microRNAs in cervical cancer cases positive or negative for HPV E6/E7 mRNA, and to assess their diagnostic usefulness and relevance. Methods: The expression of three different microRNAs (miR-9, miR-21, and miR-155) in 52 formalin-fixed paraffin-embedded (FFPE) primary cervical cancer tissue samples and 50 FFPE normal cervical tissue samples were evaluated. Results: MiR-9, miR-21, and miR-155 were significantly overexpressed in cervical cancer tissues compared to normal tissues ( P < 0.001). MiR-9, miR-21, and miR-155 expression combined with the HPV E6/E7 mRNA assay showed sensitivities of 82.7 %, 92.3 %, and 84.6 % respectively, demonstrating their potential as diagnostic tools. Moreover, miR-21 and miR-155 were predictors showing a 7 fold and 10.3 fold higher risk for HPV E6/E7 negative patients with cervical cancer ( P = 0.024 and P = 0.017, respectively) while miR-155 was a predictor showing a 27.9 fold higher risk for HPV E6/E7 positive patients with cervical cancer ( P < 0.0001). Conclusions: There is a strong demand for additional, alternative molecular biomarkers for diagnosis and management of precancer patients. MiR-9, miR-21, and miR-155 may be helpful in the prediction of both HPV positive and HPV negative cases of cervical cancer.
Flow cytometric detection of MDSC populations in unfractionated blood.
Authors: Diaz-Montero C. Marcela , Rayman Patricia A. , Kim Jin Sub , Pavicic Paul G , Tannenbaum Charles , Velcheti Vamsidhar , Funchain Pauline , Ko Jennifer S , Grivas Petros , Rini Brian I. , Montero Alberto J. , Finke James
Published: November 2019

56

Background: MDSCs are a phenotypically diverse population of bone-marrow-derived cells that play an important role in tumor progression based on their immunosuppressive and pro-angiogenic properties. Mobilization of MDSCs from the bone marrow into the blood stream is dependent on tumor derived factors. Therefore, it is likely that levels of circulating MDSCs in cancer patients are reflective of tumor activity. However, the clinical applicability of MDSCs as a predictive biomarker in cancer has been hindered by a lack of consensus on the surface markers that defines them. Although there have been several attempts at harmonizing the nomenclature and characterization standards of MDSCs, there is still a lot of confusion particularly in the detection of MDSCs in unfractionated peripheral blood. To address this issue we have devised a simple flow cytometric test that reliably detects in whole blood the MDSCs subtypes that have been consistently reported to have clinical relevance in cancer. Methods: Whole blood from cancer patients and normal volunteers was stained with Lin cocktail, HLADR, CD33, CD15, CD14, and CD11b antibodies. After staining, red blood cells were lysed, samples were washed and analyzed by flow cytometry. Results: This approach identifies monocytic MDSCs (Linlo/CD33+/HLADR-/CD14+/CD15-), granulocytic or polymorphonucleated polymorphonuclear MDSCs (Linlo/CD33+/HLADR-/CD14-/CD15+), and promyelocytic or immature MDSCs (Linlo/CD33+/HLADR-/CD14-/CD15-), as well as Linlo/HLADR-/CD33+/CD11b+ MDSCs. This latter subpopulation has been reported by us and others to correlate with disease stage and tumor burden in several solid malignancies. This assay also allows the accurate determination of absolute numbers of each MDSC population when white blood cell counts are taken into consideration. Conclusions: Our proposed simple and rapid flow cytometry-based assay allows the measurement of frequency and absolute numbers of circulating MDSC subpopulations in unfractionated blood, and could provide a reference for their further characterization as predictive biomarkers for solid malignancies.
Neurological adverse events from checkpoint inhibition: A comprehensive review of literature.
Authors: Daher Ahmad , Sudhakar Tummala
Published: November 2019

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Background: Checkpoint (CTLA-4 & PD-1) inhibitors are the most commonly used anti-cancer immunotherapeutics. Their use is associated with well-documented immune-related adverse events (iAEs), but among those, neurological adverse events (nAEs) are rare. They have been described in multiple reports but detailed analysis of the spectrum of neurotoxicities, their relationship to the drug dose, and their time course is lacking. We provide a comprehensive review of all published checkpoint inhibitors-induced nAEs. Methods: PubMed and Ovid-MEDLINE databases were queried for all nAEs from checkpoint inhibition published cases. Three additional cases from our institution were included. Clinical, radiologic, and laboratory data was reviewed and analyzed. Results: 63 cases were identified, 57 of which were analyzed in Table 1. The remaining 6 cases included nAEs occurring > 6 months after initiation of therapy and were analyzed separately. Neurotoxicity occurred after a median of 3 doses with a range of 1 to 6. Neuropathy was the most common nAE from overall checkpoint inhibition (32%) or CTLA-4 inhibition (43%) but in PD-1 blockade cases, Myasthenia Gravis (44%) was more common than neuropathy (11%). CNS demyelination (11%), encephalopathy (10%), and meningitis (6%) were also reported. Peripheral nAEs outweighed central ones by about 2:1. Improvement was seen in 77% of the cases while systemic iAEs were seen in 25% only. The 6 cases with delayed nAEs analyzed occurred 31-76 weeks after therapy initiation. Conclusions: nAEs from checkpoint inhibition typically affect PNS > CNS, occur after a few doses of therapy, and are not commonly associated with systemic iAEs. Their profile varies by type of blockade (PD-1 vs. CTLA-4). Immunotherapy may unmask a subclinical previously undiagnosed neuromuscular disorder (ex: MG). Prompt recognition and relevant testing before and during therapy is of utmost importance as a majority of cases improve with discontinuation of the drug +/- immunosuppressive therapy. [Table: see text]
Evaluating the antitumor role of B cells in patients with non-small cell lung cancer.
Authors: Bruno Tullia C.
Published: November 2019

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Background: The focus of immunotherapy has been on CD8 and CD4 tumor infiltrating lymphocytes (TILs), however, tumor infiltrating B cells (TIL-Bs) have been reported in tertiary lymphoid structures (TLS) with CD4 TILs, and both TIL-Bs and TLS correlate with NSCLC patient survival. While TIL-Bs have been identified in NSCLC patients, their function in the tumor microenvironment has been understudied with no focus on their role as antigen presenting cells (APCs) and their influence on CD8 and CD4 TILs. We hypothesize that TIL-Bs help generate potent, long-term immune responses against cancer by presenting tumor antigens to CD4 TILs. Methods: We used freshly isolated B cells from NSCLC patient tumor and tumor adjacent tissue to determine TIL-B function. We generated a specific in vitro antigen presentation assay to determine APC function and immunoregulation by TIL-Bs, and we correlated our findings with tumor-free survival. Results: We observed that the total number of B cells at the site of the tumor versus the tumor-adjacent tissue was increased compared to other immune subsets. Further, we observed three types of CD4 TIL responses when TIL-Bs presented autologous tumor antigens. There were activated responder CD4 TILs that proliferated when combined with TIL-Bs alone, which indicates stimulation with endogenous tumor antigens. There were antigen-associated responders that required exogenous autologous tumor lysate to elicit a CD4 TIL response, and there were patient CD4 TILs that did not respond to antigen presentation by TIL-Bs. Within the activated and antigen-associated responders, the TIL-B phenotype influenced the CD4 TIL phenotype; if the TIL-Bs were activated (CD69+CD27+CD21+), the CD4 TILs were T helper (anti-tumor) CD4 T cells and if the TIL-Bs were exhausted (CD69-CD27-CD21-), the CD4 TILs were T regulatory cells (pro-tumor). These data suggest that TIL-Bs influence the phenotype and function of CD4 TILs in NSCLC patient tumors. Conclusions: In conclusion, determining if TIL-Bs are activated or exhausted in NSCLC patients will determine the extent of their anti-tumor function in cancer. Ultimately, results from this study will help predict how to target TIL-B functions in future immunotherapies for NSCLC patients.
Model-based meta-analysis of safety for immune checkpoint inhibitor combinations and monotherapy.
Authors: Abdallah Kald , Shulgin Boris , Peskov Kirill , Kosinsky Yuri , Vergara-Silva Andrea , Helmlinger Gabriel , Chu Lulu , Masson Eric
Published: November 2019

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Background: Immune checkpoint inhibitors (ICIs) have shown efficacy across multiple cancer types; however, ICIs are also associated with immune-mediated (im) adverse events (AEs) especially when used in combination. Methods: Published safety data from 35 melanoma and non-small cell lung cancer clinical trials was normalized for drug exposure using drug concentrations at 50% inhibition (IC50). Pharmacokinetic models from FDA, EMEA, and our own model were used to compare AEs across 4 ICIs: anti-PD-1 (nivolumab, pembrolizumab) and anti-CTLA-4 (ipilumumab, tremelimumab). Data was analyzed by ICI target and organ class (ie, GI, skin, liver, lung, and endocrine). To test dependence of AE rate (%) on drug dose dependence (DD) we calculated mean AE rates for low and high halves of the dose range, and used Pearson’s χ2-squared test for statistical significance (SS) ( p< 0.05). Results: We found AEs to be DD for anti-CTLA-4 monotherapies and anti-CTLA-4 + anti-PD-1 combinations, whereas DD was not SS for anti-PD-1 monotherapies (Table). For anti-CTLA-4 drugs DD was SS for GI, hepatic, skin, and endocrine AEs. In combination, there was DD upon anti-CTLA-4, but data were insufficient to confirm SS. For PD-1 drugs there was no significant DD found. Conclusions: For anti-PD-1 therapy, no DD for Grade 3/4 AEs was found across organ classes. However, for anti-CTLA-4 therapies, DD was SS for GI, skin, hepatic, and endocrine im AEs. Although not all data were sufficient to confirm SS, dose intensity of anti-CTLA-4 may be an important determinant of AEs, when co-administered with anti-PD-1. [Table: see text]
Cross-Cultural Validity Study of a Medical Education Leadership Competencies Instrument in Latin American Physicians: A Multinational Study
Authors: Mano Max S. , Gomes Rafaela , Werutsky Gustavo , Barrios Carlos H. , Marta Gustavo Nader , Villarreal-Garza Cynthia , Frasson Antonio Luiz , Sternberg Cinthya , Clara Renan , Simon Sergio D. , Çitaku Fadil , Waldrop Marianne , Violato Claudio , Zillioux Don , Khan Yawar Hayat
Published: November 2019

PURPOSE

Physicians rarely receive formal training in leadership skills. Çitaku and colleagues have identified a set of leadership competencies (LCs) providing validity evidence in North American (NA) and European Union (EU) medical education institutions. We aim to apply this same survey to a sample of Latin American (LA) medical leaders from the oncology community and related areas, compare the results with those of the previous survey, and perform subgroup analyses within the LA cohort.

METHODS

The survey was sent to nearly 8,000 physicians of participating professional organizations. In addition to the 63 questions, we also collected data on the type of institution, country, specialty, sex, age, years of experience in oncology, and leadership position.

RESULTS

The 217 LA respondents placed the highest value on task management competencies (91.37% reported these as important or very important v 87.0% of NA/EU respondents; P < .0001), followed by self-management (87.45% of LA respondents v 87.55% of NA/EU respondents; P = not significant [NS]), social responsibility (86.83% of LA respondents v 87.48% of NA/EU respondents; P = NS), innovation (86.69% of LA respondents v 85.31% of NA/EU respondents; P = NS), and leading others (83.31% of LA respondents v 84.71% of NA/EU respondents; P = NS). Social responsibility, which was first in importance in the NA/EU survey, was only third in the LA survey. Subgroup analyses showed significant variations in the ratings of specific LCs within the LA population.

CONCLUSION

LCs valued by LA leaders somewhat differ from those valued by their NA and EU counterparts, implying that cultural aspects might influence the perception of desired LCs. We also detected variations in the responses within the LA population. Our data indicate that current physician leadership training programs should be tailored to suit specific needs and cultural aspects of each region. Further validity studies of this instrument with other samples and cultures are warranted.
Anesthetic Management of a Patient With an Anterior Mediastinal Mass Undergoing Endoscopic Retrograde Cholangiopancreatography in the Prone Position: A Case Report
Authors: Armas Alfredo , Primm Aaron N.
Published: November 2019

Patients with anterior mediastinal masses pose a significant challenge to anesthesiologists. Catastrophic outcomes have been described in patients with mediastinal masses undergoing anesthesia. However, despite an abundance of literature discussing anesthetic management of these patients, there is a lack of reports detailing the management of this population undergoing advanced endoscopic procedures under sedation. We report on a 28-year-old man with a large anterior mediastinal mass who underwent endoscopic retrograde cholangiopancreatography in the prone position under moderate to deep sedation without complication.
Another Role for Angiotensin II?: Vasopressin-Refractory Shock After Pheochromocytoma Resection: A Case Report
Authors: Hylton Diana J. , Minot Patrick R. , Mihm Frederick G.
Published: November 2019

A patient presented with multiple unrelated tumors and was found to have a small but functional adrenal pheochromocytoma. After pheochromocytoma resection, shock developed unresponsive to vasopressin in recommended doses (0.04 U/min infusion plus repeated 1-U boluses) but responded dramatically to an angiotensin II infusion (20 ng/kg/min) with a mean arterial pressure >100 mm Hg. The patient’s blood pressure was maintained for 42 hours postoperatively with an infusion rate that ranged from 2 to 38 ng/kg/min. Because vasopressin may not always be effective for postresection shock in people with pheochromocytomas, angiotensin II may prove to be an effective alternative.
Clevidipine-Induced Extreme Hypoxemia in a Neurosurgical Patient: A Case Report
Authors: Short Jack H. , Fatemi Parastou , Ruoss Stephen , Angelotti Timothy
Published: November 2019

Clevidipine-induced pulmonary shunting is a little-reported adverse effect, manifesting as refractory hypoxemia, which may cause significant patient harm. We present the case of a mechanically ventilated patient admitted to the intensive care unit following a neurosurgical procedure. He was treated postoperatively with clevidipine for blood pressure management, and within 16 hours, he developed profound refractory hypoxemia, requiring increased ventilatory support. A workup for other causes was negative. The hypoxemia recovered within 1 hour of clevidipine discontinuation. Though other calcium channel blockers have been reported to cause pulmonary shunting from vasodilation, this is a novel case report for clevidipine-induced hypoxemia.
Paradoxical Critical Hyperkalemia After Acetazolamide for Cerebrovascular Reactivity Study: A Case Report
Authors: Burbridge Mark A. , Jaffe Richard A.
Published: November 2019

We present the case of a 42-year-old man with moyamoya disease presenting for cerebral revascularization surgery who developed critical hyperkalemia following a single intravenous (iv) dose of 1000 mg of acetazolamide 1 day preoperatively for a cerebrovascular reactivity study. His potassium increased from 5.1 to 6.7 mmol/L. Prompt treatment of this abnormality allowed this patient to undergo surgery the next day uneventfully. A paradoxical, critical increase in potassium can result from a single 1000-mg iv dose of acetazolamide.