Citations

Abstract Purpose: Isocitrate dehydrogenase (IDH) 1/2–isoform inhibitors have clinical efficacy in IDH1/IDH2-mutated neoplasms. However, primary resistance and secondary resistance limit their therapeutic potential. LY3410738, an oral, brain-penetrant, dual IDH1/IDH2-mutated isoform-selective inhibitor, was designed to overcome resistance. Patients and Methods: This global, multicenter, open-label, phase I study of patients with IDH-mutant solid tumors evaluated LY3410738 as monotherapy (dose escalation) for advanced solid tumors in combination with cisplatin–gemcitabine (CISGEM) for newly diagnosed cholangiocarcinoma or with durvalumab for relapsed/refractory cholangiocarcinoma (dose expansion; NCT04521686). Primary objectives were the maximum tolerated dose, recommended phase II dose, and preliminary antitumor activity. Safety, pharmacokinetics, inhibition of D-2-hydroxyglutarate, and ctDNA were assessed. Results: Overall, 119 patients received LY3410738 alone (N = 94) or in combination with CISGEM (N = 19) or durvalumab (N = 6). No dose-limiting toxicities were observed; the maximum tolerated dose was not determined. Common adverse events included nausea, vomiting, and decreased appetite. Overall response rates of 5.2% and 11.1% and disease control rates of 56.9% and 63.0% were observed for patients with relapsed/refractory IDH1- or IDH2-mutant cholangiocarcinoma or IDH1-mutant glioma, respectively. D-2-hydroxyglutarate normalization was rapid and durable. In dose-expansion cohorts, combination treatments were tolerable, with one dose-limiting toxicity in the durvalumab cohort. LY3410738 plus CISGEM demonstrated a response rate of 42.1%, a median duration of response of 8.1 months, and a median progression-free survival of 10.2 months for patients with newly diagnosed IDH-mutant cholangiocarcinoma. Conclusions: LY3410738 demonstrated largely cytostatic antitumor activity in IDH1- or IDH2-mutated cholangiocarcinoma and IDH1-mutated gliomas. LY3410738 plus CISGEM exhibited favorable antitumor activity in patients with treatment-naïve IDH-mutated cholangiocarcinoma, warranting further exploration as a treatment strategy.

The development and performance of two mass spectrometry (MS) workflows for the intraoperative diagnosis of isocitrate dehydrogenase (IDH) mutations in glioma is implemented by independent teams at Mayo Clinic, Jacksonville, and Huashan Hospital, Shanghai. The infiltrative nature of gliomas makes rapid diagnosis necessary to guide the extent of surgical resection of central nervous system (CNS) tumors. The combination of tissue biopsy and MS analysis used here satisfies this requirement. The key feature of both described methods is the use of tandem MS to measure the oncometabolite 2-hydroxyglutarate (2HG) relative to endogenous glutamate (Glu) to characterize the presence of mutant tumor. The experiments i) provide IDH mutation status for individual patients and ii) demonstrate a strong correlation of 2HG signals with tumor infiltration. The measured ratio of 2HG to Glu correlates with IDH-mutant (IDH-mut) glioma ( P < 0.0001) in the tumor core data of both teams. Despite using different ionization methods and different mass spectrometers, comparable performance in determining IDH mutations from core tumor biopsies was achieved with sensitivities, specificities, and accuracies all at 100%. None of the 31 patients at Mayo Clinic or the 74 patients at Huashan Hospital were misclassified when analyzing tumor core biopsies. Robustness of the methodology was evaluated by postoperative re-examination of samples. Both teams noted the presence of high concentrations of 2HG at surgical margins, supporting future use of intraoperative MS to monitor for clean surgical margins. The power of MS diagnostics is shown in resolving contradictory clinical features, e.g., in distinguishing gliosis from IDH-mut glioma.

Abstract BACKGROUND Despite advances in cancer biology, surgery and its extent of resection remains the most important prognostic modulator in gliomas, with the distinction between infiltrated and non-infiltrated tissues being an issue at the penumbra. Isocitrate dehydrogenase (IDH) mutation is unique to IDH-mutant glioma cells and can be used as a potential surrogate for tumor infiltration. Here we evaluate desorption electrospray ionization-mass spectrometry (DESI-MS) as a near real-time method for detecting infiltration at the margin of IDH-mutant gliomas. METHODS We conducted a prospective study in which DESI-MS analysis was performed on freshly obtained tissue biopsies to detect the presence of 2-Hydroxyglutarate (2HG), with subsequent review of each sample by a board-certified neuropathologist. RESULTS A total of 247 biopsies from a 49-patient study were previously collected and analyzed at Indiana University. Assessment of IDH mutation status of 71 core biopsies yielded sensitivity, specificity, and accuracy values of 89, 100, and 94%, respectively. Subsequent improvement of the method, including the measurement of 2HG relative to an internal control (Glutamate, Glu), allowed for detection of IDH-mutant infiltration at surgical margins. We have collected 183 biopsies (116 core and 67 margin) from 23 patients. Preliminary results of IDH mutation assessments of core biopsies indicate 93% sensitivity, 100% specificity, and 98% accuracy and margin biopsies indicate 88% sensitivity, 100% specificity, and 94% accuracy. Tumor infiltration at the margin of the surgical resection by detection of IDH-mut infiltration was detected in 88% of margin biopsies from IDH mutant tumors (30 of 34 biopsies). CONCLUSION We present a novel method to allow intraoperative evaluation of IDH mutation presence in glioma margin biopsies. Our method and its ongoing validation identified tumor infiltration beyond surgical margins and serves as a foundation for molecularly guided surgery in IDH-mut gliomas via DESI-MS.

Abstract Exposure of biological systems to acute or chronic insults triggers a host of molecular and physiological responses to either tolerate, adapt, or fully restore homeostasis; these responses constitute the hallmarks of resilience. Given the many facets, dimensions, and discipline‐specific focus, gaining a shared understanding of “resilience” has been identified as a priority for supporting advances in cardiovascular health. This report is based on the working definition: “ Resilience is the ability of living systems to successfully maintain or return to homeostasis in response to physical, molecular, individual, social, societal, or environmental stressors or challenges ,” developed after considering many factors contributing to cardiovascular resilience through deliberations of multidisciplinary experts convened by the National Heart, Lung, and Blood Institute during a workshop entitled: “ Enhancing Resilience for Cardiovascular Health and Wellness.” Some of the main emerging themes that support the possibility of enhancing resilience for cardiovascular health include optimal energy management and substrate diversity, a robust immune system that safeguards tissue homeostasis, and social and community support. The report also highlights existing research challenges, along with immediate and long‐term opportunities for resilience research. Certain immediate opportunities identified are based on leveraging existing high‐dimensional data from longitudinal clinical studies to identify vascular resilience measures, create a ‘resilience index,’ and adopt a life‐course approach. Long‐term opportunities include developing quantitative cell/organ/system/community models to identify resilience factors and mechanisms at these various levels, designing experimental and clinical interventions that specifically assess resilience, adopting global sharing of resilience‐related data, and cross‐domain training of next‐generation researchers in this field.

Abstract BACKGROUND Intraoperative detection of residual tumor and isocitrate dehydrogenase (IDH) mutations can assist in maximizing surgical resection beyond contrast enhancing margins and guide intraoperative surgical decision making for glioma patients. We aimed to evaluate the use of desorption electrospray ionization-mass spectrometry (DESI-MS) for intraoperative assessment of IDH mutations and estimation of tumor cell percentage (TCP). METHODS This is a prospective study using intraoperative DESI-MS analysis of freshly obtained tissue samples to evaluate IDH mutations via 2-hydroxyglutarate (2-HG) intensity and TCP via measurement of N-acetylaspartic acid (NAA) intensity and characteristic lipid profiles. These IDH mutation and TCP estimates were subsequently validated by a senior neuropathologist. RESULTS A total of 247 biopsies from a 49-patient study were previously collected and analyzed at Indiana University. Assessment of TCP in 203 margin and core biopsies based on NAA intensity yielded sensitivity, specificity, and accuracy values of 91, 76, and 83%, whereas TCP assessment based on characteristic lipid profiles yielded 76, 85, and 81%, respectively. Assessment of IDH mutation status of 71 core biopsies yielded sensitivity, specificity, and accuracy values of 89, 100, and 94%. Further validation of the methodology is being performed in an ongoing collaboration with Mayo Clinic-Jacksonville, where we have collected 178 biopsies from 24 patients. Preliminary results of IDH mutation assessments indicate 100% sensitivity, specificity, and accuracy. DISCUSSION/CONCLUSION We present a novel system to allow intraoperative evaluation of IDH status and to guide surgical resection by TCP measurement from tissue biopsies. Prospectively, we propose to modify our DESI-MS system by placing a surgical material (e.g. cottonoid) along the surgical margin and transferring material from the blot to a microscope slide prior to DESI-MS analysis. This will allow the retention of the spatial distribution of diagnostic molecules while analyzing a wall of the surgical cavity without the need for biopsy.

The prevalence of Lynch syndrome (LS) varies significantly in different populations, suggesting that ethnic features might play an important role. We enrolled 3330 consecutive Chinese patients who had surgical resection for newly diagnosed colorectal cancer. Universal screening for LS was implemented, including immunohistochemistry for mismatch repair (MMR) proteins, BRAFV600E mutation test and germline sequencing. Among the 3250 eligible patients, MMR protein deficiency (dMMR) was detected in 330 (10.2%) patients. Ninety‐three patients (2.9%) were diagnosed with LS. Nine (9.7%) patients with LS fulfilled Amsterdam criteria II and 76 (81.7%) met the revised Bethesda guidelines. Only 15 (9.7%) patients with absence of MLH1 on IHC had BRAFV600E mutation. One third (33/99) of the MMR gene mutations have not been reported previously. The age of onset indicates risk of LS in patients with dMMR tumors. For patients older than 65 years, only 2 patients (5.7%) fulfilling revised Bethesda guidelines were diagnosed with LS. Selective sequencing of all cases with dMMR diagnosed at or below age 65 years and only of those dMMR cases older than 65 years who fulfill revised Bethesda guidelines results in 8.2% fewer cases requiring germline testing without missing any LS diagnoses. While the prevalence of LS in Chinese patients is similar to that of Western populations, the spectrum of constitutional mutations and frequency of BRAFV600E mutation is different. Patients older than 65 years who do not meet the revised Bethesda guidelines have a low risk of LS, suggesting germline sequencing might not be necessary in this population.

Abstract Marrow stromal cells (MSCs) provide important survival and drug resistance signals to chronic lymphocytic leukemia (CLL) cells, but current models to analyze CLL–MSC interactions are heterogeneous. Therefore, we tested different human and murine MSC lines and primary human MSCs for their ability to protect CLL cells from spontaneous and drug-induced apoptosis. Our results show that both human and murine MSCs are equally effective in protecting CLL cells from fludarabine-induced apoptosis. This protective effect was sustained over a wide range of CLL–MSC ratios (5:1 to 100:1), and the levels of protection were reproducible in 4 different laboratories. Human and murine MSCs also protected CLL cells from dexamethasone- and cyclophosphamide-induced apoptosis. This protection required cell–cell contact and was virtually absent when CLL cells were separated from the MSCs by micropore filters. Furthermore, MSCs maintained Mcl-1 and protected CLL cells from spontaneous and fludarabine-induced Mcl-1 and PARP cleavage. Collectively, these studies define common denominators for CLL cocultures with MSCs. They also provide a reliable, validated tool for future investigations into the mechanism of MSC–CLL cross talk and for drug testing in a more relevant fashion than the commonly used suspension cultures.