Abstract Objectives Type B aortic dissection (TBAD) is rare in patients aged ≤30 years, and data on this population remain limited. This study aimed to characterize the underlying aetiology, and outcomes of invasively treated young patients with TBAD, with a focus on the impact of heritable thoracic aortic disease (HTAD). Methods A retrospective multicentre analysis was conducted across 19 international aortic centres, including 139 patients aged ≤30 years with TBAD. Patients with chronic TBAD (n = 42) were excluded for the final analysis. The cohort was classified as uncomplicated (n = 86) or complicated (n = 53) TBAD. Clinical, radiologic, intraoperative, and postoperative data were collected using standardized forms. Outcomes were compared between subgroups defined by TBAD complexity, HTAD status, and surgical strategy. Kaplan-Meier and Andersen-Gill analyses were used for survival and recurrent aortic intervention, respectively. Results Mean follow-up time was 6.5 years. HTAD was identified in 57% of patients. Most presented with uncomplicated TBAD (62%), while high-risk uncomplicated cases were uncommon. Endovascular repair was predominant in complicated TBAD, while open repair was more frequent in uncomplicated cases. Early mortality was low (n = 3), and mid-term survival was excellent across all subgroups. HTAD was a significant predictor of recurrent aortic interventions (HR = 3.3, P = .004). No significant differences were observed in survival or reintervention rates between uncomplicated and complicated TBAD or between operative strategies. Conclusions In young patients, TBAD predominantly occurs in the context of HTAD. Both open and endovascular repair are associated with excellent early outcomes and mid-term survival. However, HTAD remains a significant predictor of recurrent aortic interventions.
USP25 Elevates SHLD2‐Mediated DNA Double‐Strand Break Repair and Regulates Chemoresponse in Cancer
AbstractDNA damage plays a significant role in the tumorigenesis and progression of the disease. Abnormal DNA repair affects the therapy and prognosis of cancer. In this study, it is demonstrated that the deubiquitinase USP25 promotes non‐homologous end joining (NHEJ), which in turn contributes to chemoresistance in cancer. It is shown that USP25 deubiquitinates SHLD2 at the K64 site, which enhances its binding with REV7 and promotes NHEJ. Furthermore, USP25 deficiency impairs NHEJ‐mediated DNA repair and reduces class switch recombination (CSR) in USP25‐deficient mice. USP25 is overexpressed in a subset of colon cancers. Depletion of USP25 sensitizes colon cancer cells to IR, 5‐Fu, and cisplatin. TRIM25 is also identified, an E3 ligase, as the enzyme responsible for degrading USP25. Downregulation of TRIM25 leads to an increase in USP25 levels, which in turn induces chemoresistance in colon cancer cells. Finally, a peptide that disrupts the USP25‐SHLD2 interaction is successfully identified, impairing NHEJ and increasing sensitivity to chemotherapy in PDX model. Overall, these findings reveal USP25 as a critical effector of SHLD2 in regulating the NHEJ repair pathway and suggest its potential as a therapeutic target for cancer therapy.
Acute type A aortic dissection in adolescents and young adults under 30 years of age: demographics, aetiology and postoperative outcomes of 139 cases
Abstract OBJECTIVES The prevalence and aetiology of acute aortic dissection type A (AADA) in patients ≤30 years is unknown. The aims of this clinical study were to determine the prevalence and potential aetiology of AADA in surgically treated patients ≤30 years and to evaluate the respective postoperative outcomes in this selective group of patients in a large multicentre study. METHODS Retrospective data collection was performed at 16 participating international aortic institutions. All patients ≤30 years at the time of dissection onset were included. The postoperative results were analysed with regard to connective tissue disease (CTD). RESULTS The overall prevalence of AADA ≤30 years was 1.8% (139 out of 7914 patients), including 51 (36.7%) patients who were retrospectively diagnosed with CTD. Cumulative postoperative mortality was 8.6%, 2.2% and 1.4%. Actuarial survival was 80% at 10 years postoperatively. Non-CTD patients (n = 88) had a significantly higher incidence of arterial hypertension (46.6% vs 9.8%; P < 0.001) while AADA affected the aortic root (P < 0.001) and arch (P = 0.029) significantly more often in the CTD group. A positive family history of aortic disease was present in 9.4% of the study cohort (n = 13). CONCLUSIONS The prevalence of AADA in surgically treated patients ≤30 years is <2% with CTD and arterial hypertension as the 2 most prevalent triggers of AADA. Open surgery may be performed with good early results and excellent mid- to long-term outcomes.
Abstract P02-02: First results of RLY-4008, a potent and highly selective FGFR2 inhibitor in a first-in-human study in patients with FGFR2-altered cholangiocarcinoma and multiple solid tumors
Abstract INTRODUCTION: Oncogenic FGFR2 alterations (fusions/rearrangements, amplifications, mutations) are key drivers in cholangiocarcinoma (CCA) and multiple solid tumors. Current pan-FGFR inhibitor (FGFRi) therapy is limited by off-isoform toxicity and acquired FGFR2 kinase domain resistance mutations. RLY-4008 is a highly selective and potent oral inhibitor designed to target both FGFR2 driver and resistance mutations. We initiated a first-in-human study in advanced solid tumors patients (pts) to define the safety, pharmacokinetics (PK) and efficacy of RLY-4008 (NCT04526106). METHODS: Adult pts received RLY-4008 QD or BID on a 4-week cycle following a BOIN escalation design. Adverse events (AEs), PK, ctDNA and anti-tumor activity (RECIST 1.1) were assessed. RESULTS: As of 16AUG21, 45 pts (35 CCA; 10 other) have been treated with RLY-4008 at total daily doses of 30-200 mg (18 pts BID; 27 pts QD). 44 pts had oncogenic FGFR2 alterations (26 fusions/13 mutations/5 amplifications). The median number of prior anti-neoplastic therapies was 3 (range 1-15). 94% (33/35) of CCA pts had prior chemotherapy and 69% (24/35) had prior FGFRi. 56% (9/16) CCA pts with prior FGFRi and evaluable ctDNA had ≥1 FGFR2 resistance mutation at baseline, most commonly at positions 549 (8/9), 617 (3/9), or 564 (2/9). RLY-4008 had rapid absorption (Tmax 1-7h), half-life to support QD dosing (18-34 h), dose-dependent exposure (AUC; Cmax) and predicted FGFR2 occupancy >85% across dose levels. The MTD has not been defined, and QD dose exploration continues to select the optimal biologically efficacious dose. AEs occurring in >20% of pts include stomatitis (49%), palmar-plantar erythrodysesthesia (PPE, 38%), dry mouth (29%), and nail toxicities (22%), majority of which were ≤Gr 2. 6 pts had Gr 1-2 retinopathy, which resolved in all cases. 5 AEs were considered dose limiting toxicities: 4 in BID (rash/PPE/mucositis/hyperbilirubinemia) and 1 in QD (retinopathy). No Gr 4/5 drug-related AEs were seen. 25 pts remain on treatment (range 1-37 weeks). RLY-4008 showed broad anti-tumor activity across dose levels and FGFR2 alterations with radiographic tumor reductions of ≥10% in 59% pts (19/32; -11% to -83%). Activity was seen in FGFRi-naïve, FGFR2-fusion+ CCA with PRs in 50% of pts (3/6, 2 confirmed and 1 pending confirmation; -56% to -83%). Activity was also seen in FGFRi pre-treated FGFR2-fusion+ CCA pts (N=16) with 16 SD, including 9 pts with tumor reduction ≥10% (from -12% to -35%). Of the FGFRi pre-treated FGFR2-fusion+ CCA patients with detectable FGFR2 resistance mutations in ctDNA at baseline, 78% (7/9) were undetectable at C2D1. CONCLUSION: RLY-4008 demonstrates promising safety, tolerability, and clinical activity in FGFR2-altered solid tumor pts, including those who progressed on prior FGFRi therapy. Consistent with the FGFR2-selective mechanism, minimal off-isoform toxicity (FGFR1-hyperphosphatemia; FGFR4-diarrhea) was seen. These encouraging data validate selective targeting of FGFR2 and suggest that RLY-4008 has potential to overcome resistance to FGFRi. Citation Format: Lipika Goyal, Mitesh Borad, Vivek Subbiah, Amit Mahipal, Suneel Kamath, Kabir Mody, Robin Katie Kelley, Richard Kim, Vaibhav Sahai, Anthony El-Khoueiry, Efrat Dotan, Oleg Schmidt-Kittler, Jinshan Shen, Kai Yu Jen, Alicia Deary, Wei Guo, Mahesh Padval, Cori Ann J. Sherwin, Charles Ferte, Beni Wolf, Alison M. Schram. First results of RLY-4008, a potent and highly selective FGFR2 inhibitor in a first-in-human study in patients with FGFR2-altered cholangiocarcinoma and multiple solid tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P02-02.
USP37 regulates DNA damage response through stabilizing and deubiquitinating BLM
Abstract The human RecQ helicase BLM is involved in the DNA damage response, DNA metabolism, and genetic stability. Loss of function mutations in BLM cause the genetic instability/cancer predisposition syndrome Bloom syndrome. However, the molecular mechanism underlying the regulation of BLM in cancers remains largely elusive. Here, we demonstrate that the deubiquitinating enzyme USP37 interacts with BLM and that USP37 deubiquitinates and stabilizes BLM, thereby sustaining the DNA damage response (DDR). Mechanistically, DNA double-strand breaks (DSB) promotes ATM phosphorylation of USP37 and enhances the binding between USP37 and BLM. Moreover, knockdown of USP37 increases BLM polyubiquitination, accelerates its proteolysis, and impairs its function in DNA damage response. This leads to enhanced DNA damage and sensitizes breast cancer cells to DNA-damaging agents in both cell culture and in vivo mouse models. Collectively, our results establish a novel molecular mechanism for the USP37–BLM axis in regulating DSB repair with an important role in chemotherapy and radiotherapy response in human cancers.
Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)
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Background and objectives It is unclear whether the presence of albuminuria modifies the effects of intensive systolic BP control on risk of eGFR decline, cardiovascular events, or mortality. Design, setting, participants, & measurements The Systolic Blood Pressure Intervention Trial randomized nondiabetic adults ≥50 years of age at high cardiovascular risk to a systolic BP target of <120 or <140 mm Hg, measured by automated office BP. We compared the absolute risk differences and hazard ratios of ≥40% eGFR decline, the Systolic Blood Pressure Intervention Trial primary cardiovascular composite outcome, and all-cause death in those with or without baseline albuminuria (urine albumin-creatinine ratio ≥30 mg/g). Results Over a median follow-up of 3.1 years, 69 of 1723 (4%) participants with baseline albuminuria developed ≥40% eGFR decline compared with 61 of 7162 (1%) participants without albuminuria. Incidence rates of ≥40% eGFR decline were higher in participants with albuminuria (intensive, 1.74 per 100 person-years; standard, 1.17 per 100 person-years) than in participants without albuminuria (intensive, 0.48 per 100 person-years; standard, 0.11 per 100 person-years). Although effects of intensive BP lowering on ≥40% eGFR decline varied by albuminuria on the relative scale (hazard ratio, 1.48; 95% confidence interval, 0.91 to 2.39 for albumin-creatinine ratio ≥30 mg/g; hazard ratio, 4.55; 95% confidence interval, 2.37 to 8.75 for albumin-creatinine ratio <30 mg/g; P value for interaction <0.001), the absolute increase in ≥40% eGFR decline did not differ by baseline albuminuria (incidence difference, 0.38 events per 100 person-years for albumin-creatinine ratio ≥30 mg/g; incidence difference, 0.58 events per 100 person-years for albumin-creatinine ratio <30 mg/g; P value for interaction =0.60). Albuminuria did not significantly modify the beneficial effects of intensive systolic BP lowering on cardiovascular events or mortality evaluated on relative or absolute scales. Conclusions Albuminuria did not modify the absolute benefits and risks of intensive systolic BP lowering.
P3634Cancer patients have a higher long-term risk of death and myocardial infarction after percutaneous coronary intervention - A matched cohort analysis of 3,560 patients
Abstract Background Cancer patients have a higher risk of thromboembolic events but it is not well known if these patients also have a higher risk of death, myocardial infarction (MI) or repeat revascularization after percutaneous coronary intervention (PCI) is unknown. Methods Cancer patients who underwent first-time single vessel PCI from January 1, 2003, through December 31, 2013 were identified by cross-matching of institutional cancer and PCI registries. These cancer patients were matched 4:1 to non-cancer patients, likewise undergoing first-time single vessel PCI in the time period. The combined primary endpoint was death, MI and revascularization at 5 year follow-up. Secondary endpoints were death and MI combined and the individual components of the primary endpoint. Both time dependent and non-time-dependent analyses were conducted. Results A total of 712 cancer patients were identified and matched to 2,848 non-cancer patients (one third women in either group). Bare-metal stents were used in one third of patients in both groups. The combined primary study endpoint was significantly more frequently encountered in the cancer than in the non-cancer group in both time-dependent (Figure 1) and non-time dependent analyses (5-year event rate 48.6% vs. 31.2%, p<0.001). This was driven by a higher 5-year event rate of death (39.0% vs. 20.1%) and MI (14.8% vs 4.86%) in the cancer group. The 5-year rate of revascularization did not differ significantly between the two groups (10.5% vs 10.3%). Figure 1. MI + revascularization-survival Conclusion Cancer patients have a two times higher rate of death and a three times higher rate of MI over the first 5 years after PCI. Future studies will need to define the etiology and factors accounting for this higher event rate in cancer patients, especially of these patients are predisposed to stent thrombosis and need longer term dual antiplatelet therapy.
Outcomes of Patients With Severe Symptomatic Aortic Valve Stenosis After Chest Radiation: Transcatheter Versus Surgical Aortic Valve Replacement
Background Patients with symptomatic severe aortic stenosis and a history of chest radiation therapy represent a complex and challenging cohort. It is unknown how transcatheter aortic valve replacement ( TAVR ) compares with surgical aortic valve replacement in this group of patients, which was the objective of this study. Methods and Results We retrospectively reviewed all patients with severe aortic stenosis who underwent either TAVR or surgical aortic valve replacement at our institution with a history of mediastinal radiation (n=55 per group). End points were echocardiographic and clinical outcomes in‐hospital, at 30 days, and at 1 year. Inverse propensity weighting analysis was used to account for intergroup baseline differences. TAVR patients had a higher STS score than surgical aortic valve replacement patients (5.1% [3.2, 7.7] versus 1.6% [0.8, 2.6], P <0.001) and more often ( P <0.01 for all) a history of atrial fibrillation (45.5% versus 12.7%), chronic lung disease (47.3% versus 7.3%), peripheral arterial disease (38.2% versus 7.3%), heart failure (58.2% versus 18.2%), and pacemaker therapy (23.6% versus 1.8%). Postoperative atrial fibrillation was less frequent (1.8% versus 27.3%; P <0.001) and hospital stay was shorter in TAVR patients (4.0 [2.0, 5.0] versus 6.0 [5.0, 8.0] days; P <0.001). The ratio of observed‐to‐expected 30‐day mortality was lower after TAVR as was 30‐day mortality in inverse propensity weighting–adjusted Kaplan–Meier analyses. Conclusions In patients with severe aortic stenosis and a history of chest radiation therapy, TAVR performs better than predicted along with less adjusted 30‐day all‐cause mortality, postoperative atrial fibrillation, and shorter hospitalization compared with surgical aortic valve replacement. These data support further studies on the preferred role of TAVR in this unique patient population.