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Introduction MYD88 L265P mutations (MUT) are found in 90% of patients with Waldenstrom macroglobulinemia (WM) and lead to the activation of pro-survival signaling. Limited literature has demonstrated that patients with MYD88 wild-type (WT) WM have poorer responses to conventional therapies and a higher likelihood of histological transformation. Increasingly the role of non-coding genomics in lymphomagenesis has demonstrated importance and currently, the epigenetic landscape of MYD88 WT WM remains underexplored. This study utilized a multi-omics approach to assess DNA methylation in MYD88 WT WM compared to MYD88 MUT patients and controls. Methods Bone marrow samples were prospectively collected from 20 subjects [3 MYD88 WT/CXCR4 WT WM, 12 MYD88 MUT WM and 5 normal controls] and positive selection for CD19+ and/or CD138+ B cells was performed. The analysis focused on the comparison between MYD88 WT WM to normal controls and MYD88-WT to MUT WM. Genome-wide DNA methylation analysis was performed, and CpG methylation ratios were segmented into 200-bp regions. Differentially methylated regions (DMRs) were determined using a Q-value <0.05 and absolute methylation difference ≥10%. Next, RNA-seq data was interrogated and differentially expressed genes (log2fold change>0.5 or <-0.5, false discovery rate<0.05) with corresponding promoter hypo- or hypermethylation were assessed. Ingenuity Pathway Analysis was used to determine potentially epigenetically regulated pathways using a corrected p<0.05. Results Comparing MYD88 WT WM samples to controls, a statistically greater number of hypermethylated DMRs were observed across genomic regions (hyper- vs hypomethylated): promoter (29129 vs 6300), 3'untranslated region (UTR) (2068 vs 1551), 5'UTR (10169 vs 735), intron (30344 vs 24511), exon (2224 vs 6855), CpG island (30372 vs 1240) and CpG shore (14477 vs 5872) (all p<0.001). Next, mRNA analysis demonstrated that 214 genes were differentially up-/downregulated with concordant promoter hypo-/hypermethylation. On the assessment of promoter-methylation-based pathways, multiple pathways involved in cell signaling, proliferation, gene regulation, cytokine and immune signaling and metabolism were found to be deregulated. Most pathways were found to be negatively enriched in MYD88 WT patients compared to controls including several members of interleukin (IL) signaling (IL-2, IL-3, IL,7) and regulators of cell proliferation and signaling including mTOR, PI3K/AKT, and p53. Positive enrichment of the PTEN, FGFR3 and ERK/MAPK pathways were observed. Underlying multiple pathways was promoter hypermethylation with corresponding mRNA downregulation of AKT3 and PIK3CA. Furthermore, promoter hypomethylation with transcript upregulation of PTEN was observed. Next, in comparison of MYD88 WT to MUT samples, a statistically greater number of hypermethylated DMRs were observed across genomic regions (hyper- vs hypomethylated): promoter (24829 vs 2544), 3'UTR (3534 vs 378), 5'UTR (6111 vs 605), intron (52292 vs 5360), exon (21066 vs 2187), CpG island (18334 vs 1551) and CpG shore (16351 vs 1957) (all p<0.001). Assessing mRNA expression, 354 genes were up-/downregulated with concordant promoter hypo-/hypermethylation. Pathway analysis revealed positive enrichment of the mitotic G1 phase to G1/S transition pathway with upregulation of the CDK4, LYN, and PSMA6 transcripts in MYD88 WT compared to MUT samples. Further, negative enrichment of cell signaling regulators including the RHO GTPase family, IL pathways (IL-4, IL-8, IL-13, IL-17) and integrin signaling were found in MYD88 WT compared to MUT samples. Underlying multiple pathways were downregulation with promoter hypermethylation of BCL2, an important regulator of apoptosis. Conclusion Genome-wide methylation analysis of MYD88 WT WM revealed a unique DNA methylation profile, with potential epigenetic alteration of key oncogenic transcripts and pathways. The negative enrichment of cell signaling and cytokine/inflammatory pathways in MYD88 WT samples compared to controls and MYD88 MUT WM suggests an epigenetic mechanism for immune evasion and potentially underlies the reduced response to conventional WM-directed therapies. Overall, this study reveals that MYD88 WT WM is epigenetically distinct from MYD88 MUT WM and regulators such as methylation may underlie the unique clinical and phenotypic properties observed.

Abstract Waldenstrom macroglobulinemia (WM) is a lymphoplasmacytic lymphoma associated with an increase in serum immunoglobulin M (IgM) monoclonal protein. The underlying causes of the disease are still not fully understood, but cells in the bone marrow (BM) microenvironment (TME) are anticipated to play a significant role in disease progression. We previously reported that myeloid-derived suppressor cells (MDSCs), a phenotypically heterogeneous group of cells known for their ability to suppress immune responses, are expanded in the bone marrow of patients with WM and that the expansion of MDSCs is particularly notable for increased numbers of polymorphonuclear MDSCs (PMN-MDSCs). In the present study, we evaluated the ability of WM cells to attract MDSCs to the tumor microenvironment (TME). We also evaluated whether PMN-MDSCs suppress the cytotoxic function of T-cells and thereby promote the survival of WM cells. Our study confirms the expansion of MDSCs, notably PMN-MDSCs in BM of WM patients as compared to normals. We also found that PMN-MDSCs expressing CD66b was a predominant population in WM patients. To determine the phenotype and transcriptome of both PMN-MDSCs and monocytic MDSCs (M-MDSCS) in WM, we compared BM aspirates from WM patients to normal bone marrow (NBM) and performed cellular indexing of transcriptomes and epitopes by sequencing (CITEseq) analysis (WM=3, NBM=2) followed by qPCR validation. We found that MDSCs in WM express significantly higher levels of HIF1-α overall (p<0.02) compared to NBM. Furthermore, PMN-MDSCs are more abundant in WM bone marrow than M-MDSCs and express significantly higher levels of CXCR4 (p<0.001), myeloperoxidase (MPO; p<0.0003), and azuricidin (AZU1; p<0.0004), suggesting an activated phenotype. To determine whether WM cells attract MDSCs to the BM, we performed a transwell assay and showed that WM cells (BCWM.1 cell line) attracted MDSCs, particularly PMN-MDSCs, to a greater extent than M-MDSCs (n=3; p<0.001). We next evaluated whether MDSCs prevent cytotoxic T-cells from lysing WM cells. In-vitro co-culture studies with BCWM.1 cells and T-cytotoxic cells (B:CD8-T) showed that T-cytotoxic cells were able to lyse the WM cell line by 46.4% , (median range 46.4 - 47.8%, p=0.001). However, when BCWM.1 cells and T-cytotoxic cells were co-cultured in the presence of MDSCs (i.e B:CD8-T:M), the specific lysis of BCWM.1 cells was reduced by 12.6% respectively (range 2.2- 12.6%, p<0.001). Furthermore, we observed that B:CD8-T:M co-culture significantly reduced CD8-T cell activation as compared to activated T cells alone (17.9%) (median range 17.8- 18%, p<0.001). In contrast, no affect was observed with B: CD8-T coculture by 91% (range 90.6- 91.4% p<.001) confirming that MDSCs suppress CD8-T cell activation. Our study therefore provides evidence that MDSCs in WM have an activated phenotype and that PMN-MDSCs in WM are attracted by malignant cells in the bone marrow. Furthermore, we find that the increased presence of PMN-MDSCs in the WM bone marrow environment suppresses T-cell lysis of malignant cells and may thereby contribute to disease progression. These findings provide a strong rationale for targeting MDSCs as a potential therapeutic strategy in WM.

Abstract OBJECTIVES The effect of allograft ischaemic time (AIT) on postoperative events after lung transplantation remains unclear. This study aims to assess the feasibility of extending the duration of AIT. METHODS The United Network for Organ Sharing database was queried for adult lung transplantation from 4 May 2005 to 30 June 2020. Patients were divided as per AIT into standard ischaemic time (<6 h) and prolonged ischaemic time (≥6 h) groups using propensity score matching and evaluated on a continuous scale using restricted cubic splines. The primary outcome was overall 1-year and 5-year survival. RESULTS Among 11 438 propensity-matched recipients, standard ischaemic time and prolonged ischaemic time showed no differences in overall 1-year (P = 0.29) or 5-year (P = 0.29) survival. Prolonged ischaemic time independently predicted early postoperative ventilator support for >48 h (OR = 1.33, 95% CI 1.22–1.44), dialysis (OR = 1.55, 95% CI 1.30–1.84), primary graft dysfunction (PGD; OR = 1.28, 95% CI 1.09–1.50), acute rejection (OR = 1.42, 95% CI 1.24–1.62), and interestingly, decreased 5-year bronchiolitis obliterans syndrome (HR = 0.91, 95% CI 0.85–0.97). In relative risk curves, 1-year mortality, prolonged ventilation, dialysis and PGD steadily increased per hour as AIT extended. The risk of acute rejection and 5-year bronchiolitis obliterans syndrome also showed significant changes between 5 and 8 h of AIT. In contrast, 5-year mortality remained constant despite rising AIT. CONCLUSIONS Prolonged AIT worsened early outcomes such as PGD, but improved bronchiolitis obliterans syndrome freedom at later time points. Despite this, both short- and long-term survival were similar between prolonged ischaemic time and standard ischaemic time patients. Dynamic risk changes in post-transplant events should be noted for prolonged ischaemia lung use.

AbstractCurrent US clinical practice guidelines for advanced prostate cancer management contain recommendations based on high‐level evidence from randomized controlled trials; however, these guidelines do not address the nuanced clinical questions that are unanswered by prospective trials but nonetheless encountered in day‐to‐day practice. To address these practical questions, the 2024 US Prostate Cancer Conference (USPCC 2024) was created to generate US‐focused expert clinical decision‐making guidance for circumstances in which level 1 evidence is lacking. At the second annual USPCC meeting (USPCC 2024), a multidisciplinary panel of experts convened to discuss ongoing clinical challenges related to 5 topic areas: biochemical recurrence; metastatic, castration‐sensitive prostate cancer; poly [ADP‐ribose] polymerase inhibitors; prostate‐specific membrane antigen radioligand therapy; and metastatic, castration‐resistant prostate cancer. Through a modified Delphi process, 34 consensus recommendations were developed and are intended to provide clinicians who manage prostate cancer with guidance related to the implementation of novel treatments and technologies. In this report, the authors review the areas of consensus identified by the USPCC 2024 experts and evaluate ongoing unmet needs regarding translational application of the current clinical evidence.

Objective To determine the frequency and accuracy of diffusion restriction (DR) of the retina and/or optic nerve (ON) detection on standard brain magnetic resonance diffusion-weighted imaging (DWI-MRI) in patients presenting with acute non-arteritic central retinal artery occlusion (CRAO). Methods This is a retrospective case-control study that includes all consecutive patients presenting to our tertiary academic center from 2013-2021 with acute non-arteritic CRAO (cases) or acute ischemic stroke syndrome (controls, age and gender-matched) that had brain MRI performed within 14 days from symptom onset. Two neurology residents (junior and senior), a vascular neurologist, and two neuroradiologists, blinded to the site of CRAO, independently reviewed the brain MRIs to assess for the presence of retina and ON DR. The consensus agreement between the two neuroradiologists was used to perform sensitivity and specificity analyses and calculate inter-rater reliability (prevalence-adjusted bias-adjusted kappa coefficient). Results A total of 128 patients with acute non-arteritic CRAO (mean (SD) age 69 (14) years; 50% female; median time from CRAO to DW-MRI 2 days (IQR 1-5)) and 128 age and gender-matched controls with acute cerebral ischemia were included. After the neuroradiologist consensus, DR was correctly identified in the retina or ON in 51/128 (39.8%) CRAO cases, retina alone 27.3%, ON alone 24.2%, and both retina and ON 11.7%, with almost perfect neuroradiologists’ inter-rater reliability for retina (K = 0.91) and ON (K = 0.83). Among controls, the retina DR was identified in 1/128 (0.8%) and ON DR in 5/128 (3.9%). The sensitivity, specificity, positive predictive value, and negative predictive value were 28.1%, 99.2%, 97.3%, and 58.0% for retina DR, and 27.3%, 96.1%, 87.5%, and 56.9% for ON DR. Conclusions Though experienced neuroradiologists identified retina and ON DR with excellent inter-rater reliability, these are infrequent findings in real world CRAO practice, with excellent specificity but limited sensitivity. Prospective studies with larger cohort of patients, optimization of standardized orbit DWI-MRI protocols are needed to facilitate a more accurate and reliable identification of retina and ON DR in acute CRAO.

Background Short-term outcomes after pancreatoduodenectomy (PD) are well-studied, but long-term reoperation rates and their indications remain poorly characterized. Methods A single-center retrospective chart review was performed on patients who underwent PD for pancreatic adenocarcinoma between 1/2011 and 12/2021. Reoperations occurring >90 days after PD were dichotomized to being related or unrelated to the index PD or pancreatic adenocarcinoma. The Kaplan-Meier analysis estimated the incidence of long-term reoperation at 1 and 5 years postoperatively. Results Six-hundred twenty-eight patients were included. The 5-year incidence of any additional operation >90 days after PD was 30.0% (95% CI 23.2-36.2%), and the 5-year incidence of any long-term related reoperation was 21.2% (95% CI 15.0-26.8%). The most common indications for reoperations by 5-year incidence were cancer recurrence (12.8%, 95% CI 7.6-17.7%), incisional hernia (6.2%, 95% CI 2.6-9.7%), small bowel obstruction (1.3%, 95% CI 0.2-2.4%), and leak, fistula, or infection (1.0%, 95% CI 0.1-2.0%). Of the examined risk factors, only 90-day reoperation was found to be predictive of long-term related reoperations ( P = 0.02). Additionally, the 5-year incidence of endoscopic or interventional radiology procedures was 20.2% (95% CI 14.5-25.4%). However, 40.9% (95% CI 33.6-47.3%) of patients required additional surgery or procedures of any kind between 90 days and 5 years after PD. Discussion Within 5 years of PD, one in three patients required additional surgery, and one in five had operations for related indications. Related reoperative indications included recurrence, hernia, PD-specific complications, and small bowel obstruction. However, the rates of each of these reoperations were relatively low.

Background: Electrodiagnostic studies are critical for surgical decision-making in nerve injuries. Surgeons typically rely on the electrodiagnostician’s reports and lack formal training in electrodiagnostic study interpretation. This knowledge gap highlights a need for accessible and effective educational resources for surgeons to improve their understanding of electrodiagnostic studies and enhance patient care. Methods: The educational module consisted of a prelecture knowledge assessment, a 42-minute video lecture on interpreting electrodiagnostic study results, and a postlecture knowledge assessment. Knowledge retention was assessed by means of an additional survey distributed 3 months after module completion. Results: This study, involving 119 participants (79% attending surgeons, 8% fellows, 9% surgical residents, and 2% who described their position as “other”), demonstrated that a 42-minute video-based learning module significantly improved knowledge of electrodiagnostic study interpretation. Median scores increased from 7 to 9 (P < 0.001), with improvement persisting at 3 months (median retention score, 11; P < 0.025). Among surgeons completing the 3-month assessment, 65.5% reported that knowledge gained from the module had changed their clinical practice. Conclusion: This study demonstrates that a concise, video-based learning module can effectively enhance surgeon knowledge of electrodiagnostic study interpretation and may serve as a valuable tool for surgical education and improving patient selection in nerve surgery.