Citations

Abstract Description Glioblastoma (GBM), the most common and malignant primary brain tumor, exhibits profound immune suppression, hindering immunotherapy efficacy. GBM-derived extracellular vesicles (EVs) play a major role through the immunosuppressive polarization of myeloid cells. Inhibition of EV-myeloid cell interactions thus represents a novel target to mitigate GBM-mediated immune suppression. However, there are multiple mechanisms of EV-target interaction, and downstream pathways of GBM-EV signaling are poorly understood. We explored two pharmacological agents targeting different mechanisms of EV uptake: Methyl-B-cyclodextrin (MBCD), which disrupts lipid rafts, and cytochalasin D, which inhibits actin polymerization. Our results showed immunosuppressive myeloid cell (CD11b+/ CD15-/ HLA-DRlow/ CD14high) populations increased upon GBM-EV treatment. Following cytochalasin D treatment, fewer immunosuppressive myeloid cells were observed (7.40%±1.01 vs. untreated 9.66%±2.86), with rescuing T cell proliferation. Conversely, MBCD treatment increased immunosuppressive myeloid cell levels (10.42%±2.38 vs. untreated 8.87%±3.97) without impacting T cell proliferation. This study demonstrates the feasibility of pharmacologically targeting EV-myeloid cell interactions to rescue tumor-mediated immune suppression by inhibiting actin-dependent endocytosis with cytochalasin D. The converse results using MBCD treatment indicate differential importance of different EV uptake pathways in monocyte regulation. Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)

Abstract Description Glioblastoma (GBM), the most common and deadly primary brain tumor in adults, is associated with profound local and systemic immune suppression. Increasing evidence points to tumor-derived extracellular vesicles (EVs) as key mediators of this immunosuppression. In surveying the tumor-immune microenvironment in samples of ultrasonic aspirate collected during surgical resection of GBM (n = 12), we identified several key immunomodulatory markers expressed across a range of immune cells in the tumor microenvironment. Particularly, we found TIGIT, classically understood as a T cell inhibitory protein, expressed across a range of myeloid cell populations, including in myeloid-derived suppressor cells (MDSCs, 46.84±16.78% of total monocytic MDSCs). Co-culture of healthy donor monocytes (n = 10) with patient-derived EVs replicated similar effects (control 11.69±1.87 vs EV treated 23.32±2.0). Furthermore, Induced MDSCs significantly inhibit T cell proliferation (30.65±5.97% proliferation, v/s control 86.47±2.94, p = 0.0001), concomitant with a surge in Th2 immune responses via TIGIT+ suppressive monocytes. Targeted TIGIT inhibition restored T cell proliferation (64.13±1.327% v/s non-inhibited, 30.65±5.97%; p = 0.02) and protective immune response, confirming a pivotal role of TIGIT in immune suppressive GBM microenvironment. Furthermore, TIGIT inhibition may unmask NLRP3 function, potentially contributing to immune rescue. Funding Sources Neurosurgery Research& Education Foundation, K12 grant Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)

Abstract Background and Aims Upadacitinib (UPA)—an oral, reversible selective Janus kinase inhibitor—has a favorable benefit–risk profile for patients with Crohn’s disease (CD) and ulcerative colitis (UC). We evaluated the benefit–risk of UPA in select subgroups with CD or UC. Methods Patients were randomized to UPA 45 mg (UPA45) once daily (QD) or placebo (PBO) induction for 12 (CD: U-EXCEED, U-EXCEL) or 8 weeks (UC: U-ACHIEVE, U-ACCOMPLISH). Clinical responders were re-randomized to QD UPA 15 mg (UPA15), UPA 30 mg (UPA30), or PBO for 52-week maintenance (CD: U-ENDURE; UC: U-ACHIEVE). This exploratory post hoc analysis assessed efficacy and safety outcomes (adverse events of special interest [AESIs]: serious infections, major adverse cardiovascular [CV] events, malignancies, and venous thromboembolic events) by CV risk, prior treatment failure, and age. Results This analysis included 1021 patients with CD and 1097 with UC during induction, and 673 with CD and 746 with UC during maintenance. Improved efficacy outcomes comparable to the overall study populations were observed with UPA versus PBO across subgroups. Patients receiving UPA30 generally showed numerically higher rates of improvements versus UPA15. AESI rates were generally comparable between UPA and PBO across subgroups except for numerically higher rates of herpes zoster and serious infections in CD with UPA. Conclusions UPA resulted in consistent benefit versus placebo across CV risk, prior treatment failure, and age subgroups. No treatment differences were seen in AESIs across subgroups except herpes zoster and serious infections, reinforcing the favorable benefit–risk profile for UPA in CD and UC seen in the overall study populations. Clinical trial numbers NCT02819635, NCT03653026, NCT03345836, NCT03345849, NCT03345823

OBJECTIVE Surgical site infection (SSI) is a leading cause of morbidity following posterior spine surgery. The optimal choice of skin closure technique depending on patient- and procedure-specific characteristics remains to be elucidated. METHODS The Neurosurgery Enterprise Registry (NER) at Mayo Clinic was queried for patients who underwent posterior spine surgery from 2017 to 2023. Propensity matching was performed to match patients on the basis of the development of SSI and baseline characteristics, including age, sex, race, and comorbidities. Perioperative outcomes were analyzed using data from the NER and medical records. RESULTS A total of 18,842 cases of posterior spine surgery were identified in the NER, and SSI was observed in 154 cases (0.8%). Of these patients, 308 patients were included in the 1:1 propensity score–matched cohort analysis, with 154 patients included in each group. Sutures were used in 224 patients (72.7%) and staples in 84 patients (27.3%) (p < 0.01). Female patients comprised 45.1% of the sutures group and 46.4% of the staples group (p = 0.8). The mean ± SD age was 59.8 ± 15.4 years in the sutures group and 60.8 ± 11.9 years in the staples group (p = 0.6). Fusion was performed in 27.2% of patients in the sutures group and 44% in the staples group (p < 0.01). Multilevel fusion comprised 68.9% of fusion cases in the sutures group and 67.6% in the staples group (p = 0.8). Comorbidities, such as diabetes (p = 0.6), hypertension (p = 0.1), and the use of disease-modifying antirheumatic drugs (DMARDs) (p = 0.5) and immunosuppressants (p = 0.2), did not differ between groups. Univariate analysis performed in the propensity score–matched cohort showed that SSI was observed in 53.6% of patients in the sutures group and 40.5% in the staples group (p = 0.04). No significant differences were noted regarding 30-day (p = 0.3), 90-day (p = 0.2), and 1-year (p = 0.3) readmissions and 30-day (p = 0.7), 90-day (p = 0.8), and 1-year (p = 0.8) reoperations. On multivariable logistic regression, SSI was not significantly associated with the choice of skin closure technique (p = 0.3). CONCLUSIONS After adjustment for spinal fusion, number of fused levels, the use of immunosuppressants, and other risk factors, SSI development was not significantly associated with the use of sutures versus staples following posterior spine surgery in our institution. Additionally, no significant differences were observed regarding baseline characteristics and other perioperative outcomes. The authors’ analysis shows that skin closure technique did not significantly affect SSI rates and other outcomes in these patients.

OBJECTIVE Lordotic devices have garnered increased attention for improving the segmental lordosis (SL) achieved with transforaminal lumbar interbody fusion (TLIF). However, it is unclear the degree to which surgeons maximize the "ideal" or listed lordosis of the interbody device. METHODS Patients undergoing one- or two-level TLIF for degenerative pathologies were identified and data were extracted on demographics, baseline lumbopelvic radiographic parameters, and TLIF details. The primary outcome of interest was the degree to which postoperative SL approximated the listed cage lordosis (Δtarget). Change in SL was a secondary outcome. Linear mixed-effects modeling was used to identify significant predictors of the percentage of ideal lordosis achieved. RESULTS A total of 239 treated levels were included (median patient age 66.6 years; 56.9% female); 151 levels were part of single-level TLIF constructs. The median segmental corrections were a 2.8° increase in SL and 2.8 mm in disc height. The median difference between listed cage lordosis and postoperative SL (Δtarget) was 0.5°. However, only 56.1% of levels achieved at least the listed cage lordosis. Linear mixed-effects modeling found that independent predictors of Δtarget were lower implant lordosis (estimate −1.01° [95% CI −1.15° to −0.87°] per degree, p < 0.001), greater preoperative SL (estimate 0.38° [95% CI 0.28°–0.48°] per degree, p < 0.001), greater preoperative PI (estimate 0.06° [95% CI 0.02°–0.11°] per degree, p = 0.007), and closer approximation of the anterior apophyseal ring of the caudal vertebrae (estimate −0.27° [95% CI −0.39° to −0.15°] per mm, p < 0.001). Similarly, independent predictors of postoperative SL were larger implant lordosis (estimate 0.16° [95% CI 0.05°–0.27°] per degree, p = 0.004), lower preoperative SL (estimate −0.70° [95% CI −0.79° to −0.62°] per degree, p < 0.001), greater preoperative PI (estimate 0.08° [95% CI 0.04°–0.12°] per degree, p < 0.001), and closer approximation of the anterior apophyseal ring of the cranial vertebrae (estimate −0.15° [95% CI −0.28° to −0.03°] per mm, p = 0.014). CONCLUSIONS The present results suggest that while lordosing, only 56% TLIF operations obtain the listed interbody lordosis ("target" lordosis). Anterior placement within the disc space is the only modifiable intraoperative technical factor for maximizing lordosis for a given interbody, highlighting the importance of effective disc space exenteration.

Abstract Background DNA methylation profiling can be used to robustly predict postsurgical outcomes and response to radiotherapy (RT) for meningioma patients. To allow for seamless integration of these complementary models into clinical practice, a practical framework is needed. Methods We leveraged a cohort of nearly 2000 surgically-treated meningiomas with DNA methylation profiling and clinical outcomes data. Existing methylation-based prediction models were dichotomized to yield four risk groups: low and high recurrent risk, each with RT sensitive and resistant subgroups. Risk groups were correlated with progression-free survival in the context of existing biomarkers including extent of resection and WHO grade. Results We first demonstrated that all risk groups benefit from gross total resection. All “high-risk, RT sensitive” tumors (n = 306, 15.7%) also benefited from adjuvant RT: after GTR, median PFS increased from 4.68 (4.13-9.48) years to not reached (P = .003); after subtotal resection (STR), from 2.12 (1.59-3.02) to 4.09 (3.41-not reached) years (P = .004). “Low-risk, RT sensitive cases” (n = 1207, 61.8%) also benefited from RT after STR (median PFS 7.39 (6.66-12.8) vs. 16.53 (10.35-not reached) years, P = .03), suggesting that RT be considered in these patients. Neither “low-risk RT resistant” (n = 84, 4.3%) nor “high-risk RT resistant” (n = 356, 18.2%) cases benefited from RT, and the latter group was associated with universally poor outcomes. Conclusions We identify methylation-defined risk groups of meningioma for which additional benefit is gained from adjuvant RT, leading to a clinical decision-making framework for straightforward integration of molecular models into clinical practice.

BACKGROUND: MODULAR antitachycardia pacing (ATP), a multicenter, international trial, assesses a modular cardiac rhythm management system: a subcutaneous implantable cardioverter defibrillator in wireless communication with a leadless pacemaker (LP) capable of pace-terminating ventricular tachycardia. METHODS: Enrolees had one or more clinical risk factors for ventricular tachycardia and did not require chronic pacing. Complications included prespecified major LP system- and procedure-related complications, and any complication related to the LP, subcutaneous implantable cardioverter defibrillator, implantation, or study protocol. Survival analysis was performed to identify complication-free rates, therapy delivery, and all-cause mortality. RESULTS: The 297 patients enrolled had an ejection fraction of 35±13%, 43% secondary prevention indications, and 59% with prior ventricular arrhythmias. Of 286 patients undergoing LP implantation (100% success), 251 patients completed 12-month follow-up. Mortality rate was 6%, with none related to the implant procedure. Median follow-up duration was 23.4 months (interquartile range, 17.9–28.1). The LP major complication-free rate was 97.2%, exceeding the performance goal. The overall LP+ subcutaneous implantable cardioverter defibrillator system-related complication-free rate was 88.5%. Appropriate tachyarrhythmia-therapy (ATP+shock) rates were 14.4%, and appropriate shock rates were 8.5%. Inappropriate total tachyarrhythmia therapy was 9.5% of which 8.5% were shocks. ATP was 67.3% successful in terminating ventricular arrhythmia episodes and accelerated ventricular arrhythmias in 10.1% of episodes. Overall therapy burden (ATP+shock) was 96/100 patient-years, of which 44/100 patient-years was for shock delivery. CONCLUSIONS: One-year outcomes of the first modular pacing-defibrillator system reveal low system and LP complication rates and good ATP efficacy rates, suggesting that the modular cardiac rhythm management is a viable alternative to single-chamber implantable cardioverter defibrillators using low-energy pacing capability without the need for transvenous leads. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov/ ; Unique identifier: NCT04798768.

Abstract Introduction/Objective Mutations in KIT and PDGFRA drive the majority of gastrointestinal stromal tumors (GIST) and inform targeted therapy selection. While single-driver mutations are typical, a subset of cases harbors multiple KIT mutations, complicating clinical interpretation. This study investigated the frequency, distribution, and inferred hierarchy of primary and secondary KIT mutations using DNA-based sequencing in a large GIST cohort. Methods/Case Report We retrospectively reviewed 579 GIST cases that underwent DNA-based next-generation sequencing using a custom panel targeting all coding exons of KIT and PDGFRA. Tumor-rich formalin-fixed paraffin-embedded (FFPE) tissue was required. In double-mutant cases, the mutation with higher variant allele frequency (VAF) was presumed to be primary. Results Mutations in KIT or PDGFRA were detected in 482/579 cases (83.2%). Among KIT-mutant cases, 28 had two mutations and one had three. Secondary mutations frequently occurred in exons 13, 14, and 17 and were significantly more common in non-gastric tumors (p &lt; 0.0001). Primary mutations most often involved exon 11. Conclusion VAF analysis enabled classification of mutation hierarchy in cases with multiple KIT mutations. The distinct anatomical and exon-specific distribution of primary vs. secondary mutations highlights their potential therapeutic implications and warrants further study.

Background: Meniscal preservation has been demonstrated to contribute to long-term knee health and has been a successful intervention in isolation and in patients with anterior cruciate ligament reconstruction (ACLR). The long-term results of meniscal repair in the setting of revision ACLR have yet to be documented. Purpose: To report the incidence of meniscal repair failures at the 6-year follow-up in a cohort of patients who underwent concurrent revision ACLR and primary meniscal repair. Study Design: Prospective cohort study; Level of evidence, 2. Methods: All revision ACLRs with concomitant primary meniscal repair cases from a multicenter group between 2006 and 2011 were selected. Six-year follow-up was obtained to determine whether any subsequent surgery had occurred since their initial revision ACLR. If so, operative reports were obtained, whenever possible, to verify pathological condition and treatment. Results: In total, 221 patients from 1234 revision ACLRs underwent concurrent primary meniscal repairs (18% of the cohort). There were 238 repairs performed: 173 medial and 65 lateral. The majority of these repairs (n = 181; 76%) were performed with an all-inside technique. Six-year surgical follow-up was obtained in 77% (171/221) of the cohort, or 189 of 238 (79%) of the repairs (136 medial, 53 lateral). The meniscal repair failure rate, defined as reoperation, was 16% (31/189) at 6 years. Of the 31 failures, 28 were medial (24 all-inside, 4 inside-out; 28/136 = 20.6% failure rate) and 3 were lateral (2 all-inside, 1 inside-out; 3/53 = 5.7% failure rate). Three medial failures were treated in conjunction with a subsequent repeat revision ACLR. Medial tears underwent reoperation for failure at a significantly higher rate than lateral tears (20.6% vs 5.7%; P = .01) and had a significantly shorter survival time compared with lateral tears ( P = .02). No difference was found between the failure and nonfailure groups when it came to tear type, tear length, repair technique utilized, suture/implant type, or number of sutures used between the 2 groups. Conclusion: Meniscal repair in the revision ACLR setting has a 16% failure rate at 6 years. Failure rates for medial tears (20.6%) were found to be higher than that for lateral tears (5.7%), which aligns with previous studies in both the revision and primary ACLR setting.