Citations

Introduction Spontaneous intracranial hypotension (SIH) caused by a spinal cerebrospinal fluid (CSF) leak classically presents with orthostatic headache. Digital subtraction myelography (DSM) has a well-established diagnostic yield in the absence of extradural spinal collection. At our institution, DSM is followed by lateral decubitus CT myelogram (LDCTM) in the same decubitus position to increase diagnostic yield of the combined study. We evaluated the incremental diagnostic yield of LDCTM following negative DSM and reviewed patient outcomes. Methods Retrospective review of consecutive DSMs with subsequent LDCTM from April 2019 to March 2021 was performed. Combined reports were reviewed, and studies with positive DSMs were excluded. Of the exams with negative DSM, only studies with LDCTM reports identifying potential leak site were included. Interventions and follow-up clinical notes were reviewed to assess symptoms improvement following treatment. Results Of the 83 patients with negative DSMs, 11 (13.2%) had positive leak findings on LDCTMs, and 21 (25.3%) were equivocal. Of 11 positive LDCTMs, 6 leaks were nerve sheath tears (NSTs) and 5 were CSF-venous fistulas (CVFs). 10/11 (90.9%) had intervention and follow-up, with 9/10 (90%) having positive clinical outcome. Of the 21 equivocal LDCTM patients (19 CVFs and 2 NSTs), 15 (71.4%) had interventions and follow-up, with 3/15 (20.0%) with positive clinical outcomes. Conclusion LDCTM following negative DSM has an incremental diagnostic yield up to 38.6%, with up to 14.5% of positive patient outcomes following treatment. LDCTM should be considered after DSM to maximize diagnostic yield of the combined exam.

AbstractIt has been challenging to target mutant KRAS (mKRAS) in colorectal cancer (CRC) and other malignancies. Recent efforts have focused on developing inhibitors blocking molecules essential for KRAS activity. In this regard, SOS1 inhibition has arisen as an attractive approach for mKRAS CRC given its essential role as a guanine nucleotide exchange factor for this GTPase. Here, we demonstrated the translational value of SOS1 blockade in mKRAS CRC. We used CRC patient‐derived organoids (PDOs) as preclinical models to evaluate their sensitivity to SOS1 inhibitor BI3406. A combination of in silico analyses and wet lab techniques was utilized to define potential predictive markers for SOS1 sensitivity and potential mechanisms of resistance in CRC. RNA‐seq analysis of CRC PDOs revealed two groups of CRC PDOs with differential sensitivities to SOS1 inhibitor BI3406. The resistant group was enriched in gene sets involving cholesterol homeostasis, epithelial−mesenchymal transition, and TNF‐α/NFκB signaling. Expression analysis identified a significant correlation between SOS1 and SOS2 mRNA levels (Spearman's ρ 0.56, p < 0.001). SOS1/2 protein expression was universally present with heterogeneous patterns in CRC cells but only minimal to none in surrounding nonmalignant cells. Only SOS1 protein expression was associated with worse survival in patients with RAS/RAF mutant CRC (p = 0.04). We also found that SOS1/SOS2 protein expression ratio >1 by immunohistochemistry (p = 0.03) instead of KRAS mutation (p = 1) was a better predictive marker to BI3406 sensitivity of CRC PDOs, concordant with the significant positive correlation between SOS1/SOS2 protein expression ratio and SOS1 dependency. Finally, we showed that GTP‐bound RAS level underwent rebound even in BI3406‐sensitive PDOs with no change of KRAS downstream effector genes, thus suggesting upregulation of guanine nucleotide exchange factor as potential cellular adaptation mechanisms to SOS1 inhibition. Taken together, our results show that high SOS1/SOS2 protein expression ratio predicts sensitivity to SOS1 inhibition and support further clinical development of SOS1‐targeting agents in CRC.

Abstract CD19 directed chimeric antigen receptor T (CART19) cell therapy has resulted in remarkable outcomes in B cell malignancies and was FDA approved in multiple indications. However, durable remissions are limited to 40% of treated patients. Inhibitory myeloid cells in tumor microenvironment have been found to suppress T cell expansion and contribute to failure of CART19 cell therapy. In this study, we aimed to unravel the interactions between monocytes, CART19 cells and tumor cells to understand how monocytes-CART19 cell interactions impact CART19 cell effector functions and clinical outcomes. Two sets of experiments were conducted, 1) use of healthy CART19 cells, CD19+ tumor cells, and healthy monocytes; 2) use of brexu-cel products from ZUMA-2 clinical trial treating mantle cell lymphoma (MCL), patient-matched monocytes and circulating MCL tumor cells (n = 11; 6 durable responders, 2 relapsed after initial response and 3 non-responders). CD28 costimulated CART19 (CART19-28ζ) cells generated in the lab from healthy donors were co-cultured with donor freshly isolated monocytes in the presence of Jeko-1 cells (a CD19+ MCL cell line). CART19 antigen specific proliferation was not inhibited by freshly isolated monocytes. When monocytes were co-cultured with CART19 and tumor cells, higher levels of eotaxin, GRO, MCP-3 and IL-7 were detected. When CART19 cells were co-cultured with the CD19+ JeKo-1 cells in the presence of ex vivo M2 polarized macrophages, CART19 antigen specific proliferation was inhibited (p=0.0045). Transwell experiments demonstrate that M2-induced CART19 inhibition is not contact dependent. Cytokine profile analysis indicated increased level of IL-1ra, IP-10 and MCP-1 and decreased level of IL-17A, sCD40L, IL-9 and MIP-1α when M2 macrophages were co-cultured with CART19 and tumor cells compared to co-cultures of tumor cells and CART19. Then we conducted ex vivo co-cultures of brexu-cel products, autologous monocytes and circulating MCL tumor cells from MCL patients (ZUMA-2) collected prior to CART19 cell infusion. Here we observed trends of elevation of IL-13 and IL-5 and reduction of GRO, MCP-3, MIP-1β and IL-8 in non-responders, compared to responders (durable responses or relapsed patients). Our results support that monocyte- and macrophage-dependent cytokine release could modulate CART19 effector and trafficking functions, and thus CART19 clinical outcomes. This warrants further investigation around strategies to improve durable responses to CART cell therapy. Citation Format: Kun Yun, Reona Leo Sakemura, Michelle J. Cox, Truc Huynh, Claudia Manriquez-Roman, Olivia Sirpilla, Carli M. Stewart, James H. Girsch, Ekene J. Ogbodo, Ismail Can, Brooke Kimball, Lionel A. Kankeu Fonkoua, Mehrdad Hefazi, Michael W. Ruff, Elizabeth L. Siegler, Mike Mattie, Sao-Mai Nguyen-Mau, Simone Filosto, Saad S. Kenderian. Impact of immunosuppressive monocytes on CART19 cell effector functions and outcomes. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4082.

Abstract While chimeric antigen receptor T-cell therapy targeting CD19 (CART19) has shown remarkable success in the treatment of hematological malignancies, the durable response rates remain approximately 40% and there are limited solutions for CART cell therapy in the treatment of solid tumors. To further understand mechanisms of resistance, including CART cell exhaustion, we employed three independent approaches: 1) RNA and ATAC sequencing on unstimulated vs. exhausted healthy donor CART19 cells by utilizing an in vitro model for exhaustion, 2) RNA and ATAC sequencing on pre-infusion CART19 cell products from responders and non-responders in the Zuma-1 clinical trial that led to the FDA approval of axi-cel CART19 therapy, and 3) a genome-wide CRISPR knockout screen in healthy donor CART19 cells using our in vitro model for exhaustion. In each of these approaches, IL-4 was identified as a regulator of CART cell dysfunction. In approach 1, ingenuity pathway analysis of genes that were both differentially accessible and expressed in exhausted compared with unstimulated CART19 cells revealed IL-4 as a top upstream regulator (p = 5E-6). In approach 2, IL-4 was one of two genes that were both upregulated and more accessible in CART19 cell products from non-responders (p &lt; 5E-2). Finally, in approach 3, gene ontology enrichment analysis of genes that were positively selected during the genome-wide CRISPR knockout screen, revealed regulation of the IL-4 pathway as one of the top affected pathways (p = 1E-4). Together, our data indicates a role for IL-4 in CART cell dysfunction caused by exhaustion. Investigating this mechanism further, we saw an increase in the production of IL-4 as CART cells became exhausted (p = 4E-3). Treatment of CART19 cells with human recombinant IL-4 (hrIL-4) resulted in dysfunction as evident by a decrease in antigen specific cytotoxicity (p = 4E-3) and proliferative ability (p= 6.5E-2), as well as exhaustion-specific signs of dysfunction such as an increase in the expression of the inhibitory receptor, TIM-3 (p = 3E-3) and an increase in the transcription of the exhaustion-related transcription factor EOMES (p = 1E-2). Finally, we tested whether IL-4 neutralization enhances CART19 cell functions. Using a CD19+ JeKo-1 xenograft mouse model, we compared the combination treatment of CART19 cells and an IL-4 neutralizing monoclonal antibody (10 mg/Kg, clone # MP4-25D2) to CART19 cells and an IgG control. IL-4 neutralization in combination with CART19 cells resulted in reduced tumor burden (p = 4.6E-2), increased CART cell proliferation (p = 8E-3), and prolonged overall survival (p= 5E-2). In summary, our data indicates that 1) IL-4 induces CART cell dysfunction through a state of exhaustion and 2) IL-4 neutralization with a monoclonal antibody enhances CART cell therapy. As such, this novel combination therapy holds the potential to be translated to the clinic to improve durable responses from CART cell therapy. Citation Format: Carli Stewart, Michelle J. Cox, Reona Sakemura, Ekene J. Ogbodo, Ismail Can, Claudia Manriquez Roman, Kun Yun, Olivia Sirpilla, James H. Girsch, Truc Huynh, Elizabeth L. Siegler, Jenny J. Kim, Mike Mattie, Nathalie Scholler, Simone Filosto, Saad S. Kenderian. IL-4 depletion leads to the improvement of CART cell therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1153.

Background and Aims: Biliary tract cancers are rare, heterogeneous cancers with poor prognoses. Bintrafusp alfa, a first-in-class bifunctional fusion protein composed of the extracellular domain of TGF-βRII (a TGF-β “trap”) fused to a human IgG1 monoclonal antibody blocking programmed death ligand 1, was evaluated in patients with locally advanced/metastatic chemorefractory biliary tract cancers. Approach and Results: This multicenter, single-arm, open-label, phase 2 study (NCT03833661) enrolled adults with locally advanced or metastatic biliary tract cancer that was intolerant to or had failed first-line systemic platinum-based chemotherapy. Patients received 1200 mg bintrafusp alfa intravenously Q2W. The primary endpoint was confirmed objective response according to Response Evaluation Criteria in Solid Tumors 1.1 assessed by IRC. Secondary endpoints included duration of response, durable response rate, safety, progression-free survival, and overall survival. Between March 2019 and January 2020, 159 patients were enrolled. Median follow-up was 16.1 (range, 0.0–19.3) months; 17 patients (10.7%; 95% CI: 6.4%–16.6%) achieved an objective response. Median duration of response was 10.0 (range, 1.9–15.7) months; 10 patients (6.3%; 95% CI: 3.1%–11.3%) had a durable response (≥6 mo). Median progression-free survival was 1.8 months (95% CI: 1.7–1.8 mo); median overall survival was 7.6 months (95% CI: 5.8–9.7 mo). Overall survival rates were 57.9% (6 mo) and 38.8% (12 mo). Grade ≥3 adverse events occurred in 26.4% of patients, including one treatment-related death (hepatic failure). Frequent grade ≥3 adverse events included anemia (3.8%), pruritus (1.9%), and increased alanine aminotransferase (1.9%). Conclusions: Although this study did not meet its prespecified primary endpoint, bintrafusp alfa demonstrated clinical activity as second-line treatment in this hard-to-treat cancer, with durable responses and a manageable safety profile.

Infectious diseases contribute significantly to the global disease burden. Sensitive and accurate screening methods are some of the most effective means of identifying sources of infection and controlling infectivity. Conventional detecting strategies such as quantitative polymerase chain reaction (qPCR), DNA sequencing, and mass spectrometry typically require bulky equipment and well-trained personnel. Therefore, mass screening of a large population using conventional strategies during pandemic periods often requires additional manpower, resources, and time, which cannot be guaranteed in resource-limited settings. Recently, emerging microfluidic technologies have shown the potential to replace conventional methods in performing point-of-care detection because they are automated, miniaturized, and integrated. By exploiting the spatial separation of detection sites, microfluidic platforms can enable the multiplex detection of infectious diseases to reduce the possibility of misdiagnosis and incomplete diagnosis of infectious diseases with similar symptoms. This review presents the recent advances in microfluidic platforms used for multiplex detection of infectious diseases, including microfluidic immunosensors and microfluidic nucleic acid sensors. As representative microfluidic platforms, lateral flow immunoassay (LFIA) platforms, polymer-based chips, paper-based devices, and droplet-based devices will be discussed in detail. In addition, the current challenges, commercialization, and prospects are proposed to promote the application of microfluidic platforms in infectious disease detection.

Abstract Objective To describe the technique, safety profile, and outcome of computed tomography (CT)–guided atlanto-axial lateral articulation injections performed at our institution. Methods Consecutive cases of all CT-guided atlanto-axial injections performed from January 2017 to April 2022 at our institution were searched in the electronic medical records. Patient charts were reviewed for demographics, characterization of pain, potential altered anatomy, pain level before and immediately after the procedure, procedure technique, complications, and follow-up outcomes, if available. Results Forty-five injections in 40 different patients were included. The average age was 67.4 years, and 28 (70%) of the patients were female. Of the 45 injections, 43 (96%) were technically successful. The average change in pain score (0–10) from immediately before to immediately after the injection was –3.36 (SD = 2.87, range = –8 to +3). Of all injections, 14 (31%) had a postprocedural pain score of zero. In 2 cases (4%), patients reported an increase in pain score immediately after the injection. In 3 cases (7%), transient non–vertebral artery vascular uptake of contrast was documented during the procedure, which could be cleared with needle repositioning. There were no complications. Conclusion CT-guided atlanto-axial lateral articulation injection is a safe procedure with a high technical success rate. It allows for direct visualization of vital structures and provides an alternative option to the traditional fluoroscopic guidance, especially in cases of prior technically unsuccessful fluoroscopically guided injection or altered anatomy.

AbstractBackgroundThis study was aimed at developing and validating a decision‐making tool predictive of overall survival (OS) for patients receiving stereotactic body radiation therapy (SBRT) for spinal metastases.MethodsThree hundred sixty‐one patients at one institution were used for the training set, and 182 at a second institution were used for external validation. Treatments most commonly involved one or three fractions of spine SBRT. Exclusion criteria included proton therapy and benign histologies.ResultsThe final model consisted of the following variables and scores: Spinal Instability Neoplastic Score (SINS) ≥ 6 (1), time from primary diagnosis < 21 months (1), Eastern Cooperative Oncology Group (ECOG) performance status = 1 (1) or ECOG performance status > 1 (2), and >1 organ system involved (1). Each variable was an independent predictor of OS (p < .001), and each 1‐point increase in the score was associated with a hazard ratio of 2.01 (95% confidence interval [CI], 1.79–2.25; p < .0001). The concordance value was 0.75 (95% CI, 0.71–0.78). The scores were discretized into three groups—favorable (score = 0–1), intermediate (score = 2), and poor survival (score = 3–5)—with 2‐year OS rates of 84% (95% CI, 79%–90%), 46% (95% CI, 36%–59%), and 21% (95% CI, 14%–32%), respectively (p < .0001 for each). In the external validation set (182 patients), the score was also predictive of OS (p < .0001). Increasing SINS<zaq;6> was predictive of decreased OS as a continuous variable (p < .0001).ConclusionsThis novel score is proposed as a decision‐making tool to help to optimize patient selection for spine SBRT. SINS may be an independent predictor of OS.

Primary cilia are microtube-based organelles that extend from the cell surface and function as biochemical and mechanical extracellular signal sensors. Primary cilia coordinate a series of signaling pathways during development. Cilia dysfunction leads to a pleiotropic group of developmental disorders, termed ciliopathy. Phosphoinositides (PIs), a group of signaling phospholipids, play a crucial role in development and tissue homeostasis by regulating membrane trafficking, cytoskeleton reorganization, and organelle identity. Accumulating evidence implicates the involvement of PI species in ciliary defects and ciliopathies. The abundance and localization of PIs in the cell are tightly regulated by the opposing actions of kinases and phosphatases, some of which are recently discovered in the context of primary cilia. Here, we review several cilium-associated PI kinases and phosphatases, including their localization along cilia, function in regulating the ciliary biology under normal conditions, as well as the connection of their disease-associated mutations with ciliopathies.