Assessment Of Drug Activity Research Articles

3D volume growth rate evaluation in the EORTC-BTG-1320 clinical trial for recurrent WHO grade 2 and 3 meningiomas.

We previously reported that tumor 3D volume growth rate (3DVGR) classification could help in the assessment of drug activity in patients with meningioma using 3 main classes and a total of 5 subclasses: class 1: decrease; 2: stabilization or severe slowdown; 3: progression. The EORTC-BTG-1320 clinical trial was a randomized phase II trial evaluating the efficacy of trabectedin for recurrent WHO 2 or 3 meningioma. Our objective was to evaluate the discriminative value of 3DVGR classification in the EORTC-BTG-1320. All patients with at least 1 available MRI before trial inclusion were included. 3D volume was evaluated on consecutive MRI until progression. 2D imaging response was centrally assessed by MRI modified Macdonald criteria. Clinical benefit was defined as neurological or functional status improvement or steroid decrease or discontinuation. Sixteen patients with a median age of 58.5 years were included. Best 3DVGR classes were: 1, 2A, 3A, and 3B in 2 (16.7%), 4 (33.3%), 2 (16.7%), and 4 (33.3%) patients, respectively. All patients with progression-free survival longer than 6 months had best 3DVGR class 1 or 2. 3DVGR classes 1 and 2 (combined) had a median overall survival of 34.7 months versus 7.2 months for class 3 (P = .061). All class 1 patients (2/2), 75% of class 2 patients (3/4), and only 10% of class 3 patients (1/10) had clinical benefit. Tumor 3DVGR classification may be helpful to identify early signals of treatment activity in meningioma clinical trials.

3D volume growth rate evaluation in the EORTC-BTG-1320 clinical trial for recurrent WHO grade 2 and 3 meningiomas.

2075 Background: We previously reported that tumor 3D volume growth rate (3DVGR) classification could help in the assessment of drug activity in patients with meningioma (Graillon et al. 2021). This classification segregates meningioma response into three main classes and a total of five subclasses (class 1 = volume decrease ≥ 25%; 2A = tumor stabilization; 2B = 3DVGR severe slowdown; 3A and 3B = respective low and quick progression) based on the 3DVGR before and under treatment. The EORTC-BTG-1320 clinical trial was a randomized phase II trial evaluating the use of trabectedin for recurrent WHO 2 or 3 meningioma (Preusser et al. 2022). Objective: To evaluate the discriminative value of 3DVGR classification for response and clinical benefit prediction in the EORTC-BTG-1320 clinical trial. Methods: All patients with at least one available additional MRI before inclusion were included. 3D volume was evaluated on all consecutive MRI until progression. 3DVGR classification was applied on them as previously described. Clinical benefit was defined as neurological and/or functional status improvement and/or steroid decrease or discontinuation. Results: 17 patients were included in this post-hoc analysis with a median age of 58 years (range, 38-73). Treatments were trabectedin, bevacizumab, hydroxyurea or palliative care in 9, 3, 2 and 3 patients respectively. At first evaluation, 3DVGR classes were 1, 2A, 2B, 3A, 3B and not evaluable in 8%, 15%, 8%, 23%, 38% and 8%, respectively. Best 3DVGR classification was 1, 2A, 3A, 3B and not evaluable in 15%, 31%, 15%, 31% and 8%, respectively. 3DVGR did not differ by methylation subgroups and NF2 or CDKN2A alterations. All patients with progression-free survival longer than 6 months presented with best 3DVGR class 1 or 2. In contrast, all patients with PFS shorter than 6 months presented with best 3DVGR class 3 or not evaluable due to early progression. Median overall survival was 34.7 months for the entire cohort. 3DVGR classes 1 and 2 (combined) had a median overall survival of 34.7 months versus 7.2 months for class 3. Best objective response according to modified Macdonald response criteria were stable disease, progression or undetermined in 8, 6 and 3 patients respectively. Regarding the 8 stable patients, they were segregated into classes 1, 2, 3 or undetermined by the 3DGVR classification in 2, 4, 1 and 1 patients, respectively. Finally, all class 1 patients, 75% of class 2 patients and only 17% of class 3 patients presented with clinical benefit (neurological and/or functional status improvement and/or steroid decrease or discontinuation), respectively. Conclusions: Tumor 3DVGR classification may be helpful to discriminate early signal of treatment activity in an independent randomized phase II clinical trial. Clinical trial information: NCT02234050 .

The DNA methylome of human vascular endothelium and its use in liquid biopsies

Vascular endothelial cells (VECs) are an essential component of each tissue, contribute to multiple pathologies, and are targeted by important drugs. Yet, there is a shortage of biomarkers to assess VEC turnover. To develop DNA methylation-based liquid biopsies for VECs, we determined the methylome of VECs isolated from freshly dissociated human tissues. A comparison with a human cell-type methylome atlas yielded thousands of loci that are uniquely unmethylated in VECs. These sites are typically gene enhancers, often residing adjacent to VEC-specific genes. We also identified hundreds of genomic loci that are differentially methylated in organotypic VECs, indicating that VECs feeding specific organs are distinct cell types with a stable epigenetic identity. We established universal and lung-specific VEC markers and evaluated their presence in circulating cell-free DNA (cfDNA). Nearly 2.5% of cfDNA in the plasma of healthy individuals originates from VECs. Sepsis, graft versus host disease, and cardiac catheterization are associated with elevated levels of VEC-derived cfDNA, indicative of vascular damage. Lung-specific VEC cfDNA is selectively elevated in patients with chronic obstructive pulmonary disease (COPD) or lung cancer, revealing tissue-specific vascular turnover. VEC cfDNA biomarkers inform vascular dynamics in health and disease, potentially contributing to early diagnosis and monitoring of pathologies, and assessment of drug activity. This work was supported by the Beutler Research Program, Helmsley Charitable Trust, JDRF, Grail and the DON Foundation (to Y.D.). Y.D holds the Walter& Greta Stiel Chair in heart studies. B.G., R.S., J.M., D.N., T.K., and Y.D. filed patents on cfDNA analysis.

Chemotherapy and targeted therapies for meningiomas: what is the evidence?

Although most meningiomas are slow growing tumors mainly controlled by surgery with or without radiotherapy, aggressive meningiomas that fail these conventional treatments constitute a rare situation, a therapeutic challenge and an unmet need in neuro-oncology. Mutational landscape in recurrent high-grade meningiomas includes mainly NF2 mutation or 22q chromosomal deletion, whereas telomerase reverse transcriptase promoter, BAP-1 and CDK2NA mutations were also found in aggressive meningiomas. Pi3K-Akt-mTOR pathway is currently the most relevant intracellular signaling pathway target in meningiomas with preliminary clinical activity observed. Assessment of drug activity with progression free survival rate at 6 months is challenging in regard to meningioma growth rate heterogeneity, so that 3-dimensional growth rate before and during treatment could be considered in the future to selected new active drugs. Despite a low evidence level, some systemic therapies may be considered for patients with recurrent meningioma not amenable to further surgery or radiotherapy. In recurrent high-grade meningioma, everolimus-octreotide combination, bevacizumab, sunitinib and peptide receptor radionuclide therapy exhibit a signal of activity that may justify their clinical use. Despite a lack of clear signal of activity to date, immunotherapy may offer new perspectives in the treatment of these refractory tumors.

The Marine Natural Compound Elatol Is a Novel Protein Translation Inhibitor with Potent Activity Against Aggressive Non-Hodgkin Lymphomas

Prognosis remains poor for patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) and other aggressive non-Hodgkin lymphomas. Targeted small-molecule signaling inhibitors have been poorly active in this setting due to a heterogeneous pathogenesis in which multiple different but overlapping signals may drive lymphomagenesis. Activation of cap-dependent protein translation is a convergence point of multiple lymphoma drivers, including B-cell receptor (BCR) signaling pathways. Cap-dependent protein translation begins with formation of the eIF4F complex, a heterotrimeric complex comprised of the cap-binding protein eIF4E, the scaffold protein eIF4G, and the ATP-hydrolyzing RNA helicase eIF4A, which is required for expression of many oncogenes, including the common lymphoma driver MYC. Despite evidence that disruption of eIF4F function is toxic to lymphoma cell lines and sensitizes mouse models of lymphoma to chemotherapy, eIF4A inhibitors have not progressed to clinical evaluation. We designed a screen to identify novel eIF4A inhibitors by measuring ATP hydrolysis and screened a collection of ~1,200 natural compounds and purified extracts. The marine natural product elatol was the top hit in our screen, showing selectivity for eIF4A over other DEAD-box family helicases and a panel of 97 common kinases. Elatol inhibits eIF4A's helicase activity in cell-free in vitro assays and binds to the target at a 2:1 ratio through interaction with two key lysine residues that fold together in its RNA-binding groove. It also induced apoptosis in a broad range of cancer cell lines from the NCI-60 (average LD50= 1.9 μM; LD50<1μM in 33/60) cancer cell line and CCLE panels, but our collection of non-Hodgkin lymphoma lines showed the greatest sensitivity as a group (average LD50= 1.3 μM; 9/12 <1μM; range 213-5749nM). In DLBCL cell lines, Elatol treatment reduced global protein translation measured through polysome profiling and O-propargyl puromycin incorporation as well as cap-dependent translation measured by luciferase reporter and western blotting. Elatol also blocked translational activation downstream of BCR stimulation in primary chronic lymphocytic leukemia (CLL) cells. The effects of elatol are similar to the rocaglate silvestrol, which inhibits eIF4A though through a different mechanism, but elatol requires higher concentrations to achieve these effects. Elatol's reduced in vitro potency, however, is off-set by a maximum tolerated in vivo dose to mice of 65mg/kg, compared to silvestrol's typical dosing at 0.2-05 mg/kg. Elatol significantly reduced the growth of DLBCL tumors in a xenograft model. Mechanistically, elatol and silvestrol both clearly function downstream of mTOR for translational inhibition, but unlike silvestrol, elatol causes strong and rapid induction of the stress response transcription factor ATF4. Assessment of drug activity in murine embryonal fibroblasts lacking ATF4 and those with an unphosphorylatable mutant allele of its upstream activator eIF2α shows elatol's anti-lymphoma activities are not dependent on ATF4 induction. In addition, an inhibitor of the eIF2α kinase PERK and other evidence demonstrate elatol does not produce an unfolded protein response, but the reason for ATF4 induction is not yet clear and additional eIF2α kinases are under investigation. The novel mechanism of inhibition of ATP hydrolysis may be driving these unique observations compared to other eIF4A inhibitors, but unexpected off targets are also under evaluation. In sum we report a new natural inhibitor of protein translation with potent anti-lymphoma activities. Elatol provides a novel starting point for development of eIF4A inhibitors in cancer therapeutics. DisclosuresNo relevant conflicts of interest to declare.

NI-09 * HIGH RESOLUTION THREE-DIMENSIONAL HISTOLOGICAL RECONSTRUCTION OF GLIOMA SPHEROIDS AND APPLICATION IN RESEARCH

BACKGROUND: Glioblastomas are highly malignant tumours characterized by an invasive phenotype, which limits response to standard treatment including surgery, radiation and chemotherapy. Targeting the migratory properties of glioma cells may offer an alternative means to improve disease management. We recently developed a 96 well-based in vitro collagen invasion assay to study the effect of anti-migratory drugs on glioma spheroids generated from patient derived and established cell lines. One limitation of this 3D technique is the quantitative assessment of drug activity as data is subjected to 2D analysis. Here we explored the feasibility of analysing spheroids and migratory cells using 3D image reconstruction. METHODS: Glioma spheroids (U87) were allowed to migrate into a collagen matrix over 72h and prepared for immunohistochemistry. Paraffin embedded spheroids were serially sectioned at 5 µM. A total of 50 slides per spheroid were stained using H&E for reconstruction of the whole spheroid and surrounding migratory rim. Slides were scanned with Aperio AT scanner at 20x magnification, and custom image registration software was used to generate and view 3D volumes. This software uses a novel method for slice-to-slice image registration using automatic registration algorithms custom designed for virtual slides and histopathology images RESULTS: By visualizing the fixed spheroids in 3D, we determined the number, morphology and distance traversed by migratory cells. We also ascertained differences between core and migrating cell morphology, number of cells and voxel sizes. CONCLUSIONS: We have demonstrated for the first time the feasibility of generating 3D histological reconstruction of glioma spheroids and migratory cells encased in collagen including whole slide scanning, image serving, registration and visualization in one procedure. Analysis of the glioma spheroids and the migratory cells allowed the quantitative analysis of research-relevant parameters. This technology can be used to analyse migratory behavior of glioma cells and drug activity in a 3D setting.

Use of tumor growth rate (TGR) to provide useful clinical information in phase I trials and reveal clear drug-specific profiles.

3010 Background: The evaluation of treatment response by RECIST does not take into account the tumor growth kinetics along the treatment sequence and may induce misleading information regarding the evaluation of the drug activity. TGR incorporates the time between the tumor evaluations and allows for a dynamic and quantitative evaluation of the tumor kinetics. How TGR is modified along the introduction of experimental therapeutics and is associated with outcome in phase I patients remains unknown. Methods: Medical records from all patients (n=304) prospectively treated at Institut Gustave Roussy in 19 phase I trials between 2009 and 2011 were analyzed. TGR was computed both during the pre-treatment period (REFERENCE) and between baseline and first evaluation (EXPERIMENTAL). TGR is defined as: log 10 (Vt/V0)/dt and is represented as a percentage increase of tumor volume per month for clinical relevance. The associations between TGR, RECIST, the most commonly used prognostic scores (ECOG, RMH score, PFS ratio) and the outcome (OS, PFS) were computed (multivariate analysis). The effect of treatment, prognostic scores, histology, and the number of previous treatment lines on TGR were assessed. Results: Overall, we observed a reduction of TGR between the REFERENCE vs. EXPERIMENTAL periods (11.5 vs. 1.5, P&lt;.0001). Although most of the patients were classified as stable disease (57%) or progressive disease (28%) by RECIST at the first evaluation, 88% and 69% of them exhibited a decrease in TGR, respectively. TGR reveals clear drug specific profiles along the 19 experimental regimens tested, allowing for an early evaluation of the drug activity. The TGR decrease was associated with both PFS (P=.004) and OS (P=.001) and remained significant even after adjustment to the other prognostic scores for phase I patients. Conclusions: Adding TGR assessment in phase I patients is simple and provides clinically relevant information: (i) It allows for an early and precise assessment of the tumor growth, (ii) It reveals drug-specific profiles, suggesting its potential use for the early assessment of drug activity, (iii) TGR is independently associated with prognosis in phase I patients.

Abstract 3363: Pharmacodynamic (PD) assessment of drug activity in tumor tissue from patients (pts) enrolled in a Phase I study of MEHD7945A (MEHD), a first-in-class HER3/EGFR dual action antibody, in pts with locally advanced or metastatic epithelial tumors.

Abstract Background Members of the human epidermal growth factor receptor (HER) family of oncogenes are often co-expressed and heterodimerized, suggesting that simultaneous blockade of multiple HER family receptors may be more effective than targeting single receptors. MEHD is a dual-action human IgG1 antibody that can bivalently bind to HER3 and EGFR and block ligand binding to either. FDG-PET imaging is a recognized method of assessing PD modulation with EGFR inhibitors in the clinic. HER3 and EGFR signaling via the MAPK and PI3K pathways can be monitored in tissue by examining phosphorylation of downstream markers. Methods A Phase 1, multicenter, open-label study was conducted to evaluate the safety, pharmacokinetics, and anti-tumor activity of MEHD administered intravenously every 2 weeks at doses ranging from 1 to 30 mg/kg during escalation (n=30), and at 14 mg/kg during expansion (n=36). FDG-PET scans and optional tumor biopsies (bxs) were obtained at baseline and cycle 2, day 2 (C2D2). Tumor bxs were evaluated by immunohistochemistry (IHC) for S235/236-p-S6, T246-p-PRAS40, and T202/Y204-p-MAPK. EGFR and KRAS mutation (mt) status was determined by PCR. Paired frozen bxs were utilized for exploratory assessment by reverse-phase protein arrays (see Penuel et al. abstract). Results Evidence of PD modulation by imaging or IHC was observed in 14 pts including 7 CRC (KRAS mt-2, wt-5), 3 NSCLC, 2 SCCHN, 1 ovarian, and 1 anal cancer. Tumor FDG-uptake was decreased by at least 20%, indicating a partial metabolic response (PMR), in 9/56 evaluated pts (16%). Tumor bxs were obtained at baseline and C2D2 from 32 pts (12 escalation, 20 expansion). Sufficient viable tumor for IHC was present in both bxs from 17/32 evaluated pts. IHC signal was decreased for one or more of the 3 markers in the C2D2 bxs of 6/17 pts (35%), 5 CRC (KRAS mt-2, wt-3), 1 NSCLC. Best response by CT-RECIST includes PR in 2 patients with SCCHN, both with PMR and both tumors expressing high heregulin, with duration of response of 10 and 12+ months. Conclusions Evidence of PD modulation is demonstrated by a PMR rate of 16% and reduced pathway activity by IHC in 35% of pts with evaluable biopsies. These data suggest MEHD is biologically active in pts and downregulates intracellular signaling activity consistent with HER3 and/or EGFR inhibition in tumor tissue and is further supported by evidence of anti-tumor activity. Phase II studies in SCCHN and CRC are ongoing. Citation Format: Dejan Juric, Rodrigo Dienstmann, Andres Cervantes, Manuel Hidalgo, Wells Messersmith, George Blumenschein, Jose Baselga, Josep Tabernero, Desamparados Roda, Antonio Calles, Antonio Jimeno, Lukas Amler, Howard Stern, Sandra Sanabria, Elicia Penuel, Andrea Pirzkall. Pharmacodynamic (PD) assessment of drug activity in tumor tissue from patients (pts) enrolled in a Phase I study of MEHD7945A (MEHD), a first-in-class HER3/EGFR dual action antibody, in pts with locally advanced or metastatic epithelial tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3363. doi:10.1158/1538-7445.AM2013-3363

An In Vivo Platform for Rapid High-Throughput Antitubercular Drug Discovery

Treatment of tuberculosis, like other infectious diseases, is increasingly hindered by the emergence of drug resistance. Drug discovery efforts would be facilitated by facile screening tools that incorporate the complexities of human disease. Mycobacterium marinum-infected zebrafish larvae recapitulate key aspects of tuberculosis pathogenesis and drug treatment. Here, we develop a model for rapid in vivo drug screening using fluorescence-based methods for serial quantitative assessment of drug efficacy and toxicity. We provide proof-of-concept that both traditional bacterial-targeting antitubercular drugs and newly identified host-targeting drugs would be discovered through the use of this model. We demonstrate the model's utility for the identification of synergistic combinations of antibacterial drugs and demonstrate synergy between bacterial- and host-targeting compounds. Thus, the platform can be used to identify new antibacterial agents and entirely new classes of drugs that thwart infection by targeting host pathways. The methods developed here should be widely applicable to small-molecule screens for other infectious and noninfectious diseases.

Growth modulation index and RECIST-based STBSG-EORTC criteria for the assessment of drug activity in advanced soft tissue sarcoma (ASTS) patients (pts).

10014 Background: Despite promising phase II trial results, most of new drugs failed to improve the overall survival (OS) in ASTS pts. The choice of the endpoint in early trials remains crucial. We have evaluated the Growth Modulation Index (GMI) as potential endpoint. The GMI is defined as the Time To Progression with the second (or n+1) line of chemotherapy (TTP2) divided by the TTP with the first (or n) line (TTP1). Methods: We have carried out a retrospective multicenter study in pts receiving second-line chemotherapy after failure/intolerance to doxorubicin-based regimens. Data collected included best response(s), TTP1 &amp; TTP2 and OS. Treatments have been classified as "active" treatment according to the EORTC- STBSG criteria (3-month Progression-free rate &gt;40% or 6-month PFR&gt;14%: including trabectedin, ifosfamide, gemcitabine+docetaxel for all subtypes and weekly paclitaxel for angiosarcoma) versus non-active drugs. Comparisons used chi-2 tests and Log-rank tests. We performed a logistic regression analysis for identifying factors associated with longer GMI. Results: The study population consisted in 106 men and 121 women, the median age was 57 years. 110 pts (48.4%) have received "active drugs". The median TTP1, TTP2 and GMI were 197 days, 134 days and 0.75, respectively. The median OS was 446 days. 70 pts experienced GMI&gt;1.33 (30.6%). There was a strong relation between best objective response and GMI (p&lt;0.0001). The treatment with "active drug" was not associated with an improvement of the OS: 490 days 407 versus days (p=0.524). The median OS of pts with GMI&lt;1, GMI=[1.00-1.33] and GMI&gt;1.33 were 324, 302 and 710 days, respectively (p&lt;0.0001). None of the following factors were associated with GMI&gt;1.33 in logistic regression analysis: age, gender, histological subtypes, grade, metastasis locations, interval between diagnosis &amp; metastasis, association with ifosfamide or dacarbazine in 1st-line regimen or treatment with "active drug" in second-line. Conclusions: GMI seems to be an interesting endpoint providing additional information compared to classical criteria. GMI&gt;1.33 is associated with significant improvement of the OS.

Predictive tests for individualization of pharmacological cancer treatment

The selection of cancer drugs for an individual patient is still based mostly on cancer type and stage. Predictive tests are needed to make individualized and more efficient pharmacological cancer treatment possible. To provide an overview of available, possible future development and principles for development of predictive tests for individualized selection of cancer drugs. Overview of published data. Despite increased knowledge in cancer biology, only limited progress has been made in the development and use of predictive tests. However, rapid progress in this field will be possible using already available and emerging technologies, but requires a paradigm shift in principles for the development and use of cancer drugs. Assessment of drug activity in intact tumor cells and tumor cell gene expression signatures are considered to have greatest potential for the development of versatile predictive tests.

Assessment of Drug Activity and Proliferation Ex Vivo for Prediction of Outcome in Aggressive Non-Hodgkin's Lymphomas

The activity of cytotoxic drugs and tumour cell proliferation rate were assessed ex vivo using the fluorometric microculture cytotoxicity assay (FMCA) and stainings for Ki67 and mitosis in 40 patients with aggressive non-Hodgkin's lymphomas (NHL). The findings were correlated to clinical response and survival. Twenty-three patients had a complete remission and 10 a partial remission. A drug sensitivity index based on the cell survival for three major drugs in NHL treatment was derived empirically and proliferation was expressed as low-, intermediate- or high. In 5 out of 8 drugs tested, cell survival ex vivo was higher in clinical non-responders than that in responders. Using the median drug sensitivity index as a cut-off, the sensitivity and specificity for tumour response were 58% and 100%, respectively, and was similar for the proliferation index. Both indices combined increased the sensitivity to 73% at retained specificity. Intermediate/high proliferation was significantly associated with impaired survival, whereas the drug sensitivity index was not predictive of survival. Thus, ex vivo assessments of drug sensitivity and proliferation seem to provide prognostic information in aggressive NHL.

Effect of Non-narcotic Analgesics on Membrane Permeability of Molluscan Neurones

IT is difficult to study how analgesics act: not only are the pharmacokinetics complex, but assessment of drug activity is subjective. Certain discrepancies occur regarding the analgesic potency of several compounds and also disagreement concerning their site of action1–4. No proposed mechanism of action2,3 is widely accepted.