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In this article we consider the Dirichlet problem on a bounded domain $\Omega \subset {\bf R}^d$ with respect to a second-order elliptic differential operator in divergence form. We do not assume a divergence condition as in the pioneering work by Stampacchia, but merely assume that $0$ is not a Dirichlet eigenvalue. The purpose of this article is to define and investigate a solution of the Dirichlet problem, which we call Perron solution, in a setting where no maximum principle is available. We characterise this solution in different ways: by approximating the domain by smooth domains from the interior, by variational properties, by the pointwise boundary behaviour at regular boundary points and by using the approximative trace. We also investigate for which boundary data the Perron solution has finite energy. Finally we show that the Perron solution is obtained as an $H^1_0$-perturbation of a continuous function on $\overline \Omega$. This is new even for the Laplacian and solves an open problem.

Predictieve moleculaire diagnostiek speelt een belangrijke rol bij het bepalen van de behandelmogelijkheden voor patiënten met (gemetastaseerd) niet-kleincellig longcarcinoom (NSCLC). De meeste patiënten met NSCLC worden gediagnostiseerd en behandeld in een niet-academisch ziekenhuis. Deze ziekenhuizen verrichten zelf predictieve moleculaire diagnostiek of besteden dit uit aan een laboratorium in het regionale netwerk van academische en perifere ziekenhuizen en laboratoria. Eerder onderzoek heeft laten zien dat bij een deel van de patiënten met (stadium IV) NSCLC geen of onvolledige moleculaire diagnostiek wordt verricht. Daardoor kan voor deze patiënten geen optimale behandelkeuze voor beschikbare (doelgerichte) geneesmiddelen worden gemaakt. Om in kaart te brengen waarom dit zo is en hoe dit kan worden verbeterd, is in 2020 het project ‘Landelijke implementatie predictieve analyses bij longkanker op regionaal niveau’ gestart. Hierin wordt de workflow van de moleculaire diagnostiek onderzocht binnen zes regionale netwerken in Nederland. In de regio Noord-Nederland is sinds de start van het project een aantal stappen gezet om belemmeringen te identificeren en het aantal patiënten voor wie geen volledige predictieve diagnostiek wordt verricht, te verminderen. In dit overzichtsartikel worden deze stappen, de onderliggende rationale en de ervaringen tot nu toe uiteengezet.

XLSX file - 32K, Phosphorylation of downstream intracellular kinases.

Although most children with acute myeloid leukemia (AML) achieve complete remission, the relapse rate is 30% to 40%. Because it is thought that leukemia-initiating cells (LIC) are responsible for AML relapses, targeting these cells might improve outcome. Treatment of pediatric AML blasts with the receptor tyrosine kinase (RTK) inhibitor PTK787/ZK 222584 (PTK/ZK) induces cell death in vitro. However, the role of PTK/ZK inhibition on outgrowth of (pediatric) LICs is unknown. In this study, we cultured CD34+ cells from pediatric patients with AML on MS5 stromal cells in long-term cocultures. In analogy to adult AML, long-term expansion of leukemic cells up to 10 weeks could be generated in 9 of 13 pediatric AMLs. Addition of PTK/ZK to long-term cocultures significantly inhibited leukemic expansion in all samples, ranging from 4% to 80% growth inhibition at week 5 compared with untreated samples. In 75% of the samples, the inhibitory effect was more pronounced at week 10. Proteome profiler array analysis of downstream kinases revealed that PTK/ZK reduced activation of PI3K/Akt kinase signaling. Although main targets of PTK/ZK are VEGF receptors (VEGFR), no effect was seen on outgrowth of LICs when cultured with bevacizumab (monoclonal VEGFA-antibody), specific antibodies against VEGFR2 or VEGFR3, or exposed to stroma-derived VEGFA. These data suggest that the effect of PTK/ZK on LICs is not only dependent on inhibition of VEGFA/VEGFR signaling. Taken together, our data elucidated antileukemic properties of PTK/ZK in long-term expansion cultures, and suggest that targeting multiple RTKs by PTK/ZK might be a potential effective approach in eradicating (pediatric) LICs. Mol Cancer Res; 11(4); 339–48. ©2013 AACR.

XLSX file - 21K, Specific primers for RT-PCR.

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PDF file - 147K, Effect of VEGFA-addition, Bevacizumab, specific VEGFR-inhibitor and MK2206 on CD34+ sorted pediatric AML cells.

PDF file - 161K, Effect of PTK787/ZK 222584 and MK2206 on AML cell lines.

High expression of VEGFC predicts adverse prognosis in acute myeloid leukemia (AML). We therefore explored VEGFC-targeting efficacy as an AML therapy using a VEGFC mAb. VEGFC antibody therapy enforced myelocytic differentiation of clonal CD34+ AML blasts. Treatment of CD34+ AML blasts with the antibody reduced expansion potential by 30% to 50% and enhanced differentiation via FOXO3A suppression and inhibition of MAPK/ERK proliferative signals. VEGFC antibody therapy also accelerated leukemia cell differentiation in a systemic humanized AML mouse model. Collectively, these results define a regulatory function of VEGFC in CD34+ AML cell fate decisions via FOXO3A and serve as a new potential differentiation therapy for patients with AML.Significance: These findings reveal VEGFC targeting as a promising new differentiation therapy in AML. Cancer Res; 78(20); 5940–8. ©2018 AACR.

Complete supplementary Data file including supportive figures that highlight: VEGFC targeting potential in pediatric AML, VEGFC/KDR complex molecular targeting in AML, and VEGFC antibody induced differentiation phenotype in AML, and supplementary tables include the patient characteristics, used antibodies and primer sequences, and FLT3-ITD ratio's

Progression in pediatric brain tumor growth is thought to be the net result of signaling through various protein kinase-mediated networks driving cell proliferation. Defining new targets for treatment of human malignancies, without a priori knowledge on aberrant cell signaling activity, remains exceedingly complicated. Here, we introduce kinome profiling using flow-through peptide microarrays as a new concept for target discovery. Comprehensive tyrosine kinase activity profiles were identified in 29 pediatric brain tumors using the PamChip kinome profiling system. Previously reported activity of epidermal growth factor receptor, c-Met, and vascular endothelial growth factor receptor in pediatric brain tumors could be appreciated in our array results. Peptides corresponding with phosphorylation consensus sequences for Src family kinases showed remarkably high levels of phosphorylation compared with normal tissue types. Src activity was confirmed applying Phos-Tag SDS-PAGE. Furthermore, the Src family kinase inhibitors PP1 and dasatinib induced substantial tumor cell death in nine pediatric brain tumor cell lines but not in control cell lines. Thus, this study describes a new high-throughput technique to generate clinically relevant tyrosine kinase activity profiles as has been shown here for pediatric brain tumors. In the era of a rapidly increasing number of small-molecule inhibitors, this approach will enable us to rapidly identify new potential targets in a broad range of human malignancies. [Cancer Res 2009;69(14):5987–95]

Supplementary Table 3 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Figure Legend from Repression of Vascular Endothelial Growth Factor Expression by the Runt-Related Transcription Factor 1 in Acute Myeloid Leukemia

Supplementary Figure 3 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Figure 2 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Table 4 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Figure 1 from Repression of Vascular Endothelial Growth Factor Expression by the Runt-Related Transcription Factor 1 in Acute Myeloid Leukemia

Supplementary Figure 1 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Table 2 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Figure 4 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

Supplementary Table 1 from Kinome Profiling in Pediatric Brain Tumors as a New Approach for Target Discovery

We prove a generalized Birman-Schwinger principle in the non-self-adjoint context. In particular, we provide a detailed discussion of geometric and algebraic multiplicities of eigenvalues of the basic operator of interest (e.g., a Schrodinger operator) and the associated Birman-Schwinger operator, and additionally offer a careful study of the associated Jordan chains of generalized eigenvectors of both operators. In the course of our analysis we also study algebraic and geometric multiplicities of zeros of strongly analytic operator-valued functions and the associated Jordan chains of generalized eigenvectors. We also relate algebraic multiplicities to the notion of the index of analytic operator-valued functions and derive a general Weinstein-Aronszajn formula for a pair of non-self-adjoint operators.

Given a complex, elliptic coefficient function we investigate for which values of p the corresponding second-order divergence form operator, complemented with Dirichlet, Neumann or mixed boundary conditions, generates a strongly continuous semigroup on $$\mathrm {L}^p(\Omega )$$ . Additional properties like analyticity of the semigroup, $$\mathrm {H}^\infty $$ -calculus and maximal regularity are also discussed. Finally, we prove a perturbation result for real coefficients that gives the whole range of p’s for small imaginary parts of the coefficients. Our results are based on the recent notion of p-ellipticity, reverse Holder inequalities and Gaussian estimates for the real coefficients.

Contains fulltext : 288327.pdf (Publisher’s version ) (Open Access) INTRODUCTION: Patients with life-threatening advanced non-small cell lung cancer (NSCLC) who harbor an exon 20 deletion and/or insertion mutation (EGFRex20 + ) have limited effective treatment options. The high dose 3rd generation tyrosine kinase inhibitor (TKI) osimertinib shows promising in vitro activity in EGFRex20 + NSCLC tumors. METHODS: The POSITION20 is a single arm phase II, multicenter study investigating 160 mg osimertinib in patients with EGFRex20+, T790M negative NSCLC. We allowed patients to be treatment naïve and to have asymptomatic brain metastases. The primary endpoint was overall response rate (ORR). Secondary outcomes were duration of response (DoR), progression free survival (PFS), overall survival (OS), and treatment related adverse events (trAEs). RESULTS: From June 2018 to October 2021, 25 patients were enrolled across five centers in the Netherlands. The median age was 70 years (range, 47-87), 20 patients (80%) were women, and the median number of previous lines of therapy was 1 (range, 0-3). The exon 20 mutations were clustered between A763 and L777. The most common exon 20 mutations were p.(N771_H773dup) (n = 3) and p.(A767_V769dup) (n = 3). The ORR was 28% (95% CI, 12-49%), including seven partial responses, with a median DoR of 5.3 months (range, 2.7-27.6). The median PFS was 6.8 months (95% CI, 4.6-9.1) and the median OS was 15.2 months (95% CI, 14.3-16.0). The most common trAEs were diarrhea (72%), dry skin (44%), and fatigue (44%). The primary reason for discontinuation was progressive disease in 14 patients (56%). CONCLUSION: The POSITION20 study showed modest antitumor activity in patients with EGFRex20 + NSCLC treated with 160 mg osimertinib, with a confirmed ORR of 28% and acceptable toxicity.

Background Molecular tumor boards (MTBs) provide rational, genomics‐driven, patient‐tailored treatment recommendations. Worldwide, MTBs differ in terms of scope, composition, methods, and recommendations. This study aimed to assess differences in methods and agreement in treatment recommendations among MTBs from tertiary cancer referral centers in The Netherlands. Materials and Methods MTBs from all tertiary cancer referral centers in The Netherlands were invited to participate. A survey assessing scope, value, logistics, composition, decision‐making method, reporting, and registration of the MTBs was completed through on‐site interviews with members from each MTB. Targeted therapy recommendations were compared using 10 anonymized cases. Participating MTBs were asked to provide a treatment recommendation in accordance with their own methods. Agreement was based on which molecular alteration(s) was considered actionable with the next line of targeted therapy. Results Interviews with 24 members of eight MTBs revealed that all participating MTBs focused on rare or complex mutational cancer profiles, operated independently of cancer type–specific multidisciplinary teams, and consisted of at least (thoracic and/or medical) oncologists, pathologists, and clinical scientists in molecular pathology. Differences were the types of cancer discussed and the methods used to achieve a recommendation. Nevertheless, agreement among MTB recommendations, based on identified actionable molecular alteration(s), was high for the 10 evaluated cases (86%). Conclusion MTBs associated with tertiary cancer referral centers in The Netherlands are similar in setup and reach a high agreement in recommendations for rare or complex mutational cancer profiles. We propose a “Dutch MTB model” for an optimal, collaborative, and nationally aligned MTB workflow. Implications for Practice Interpretation of genomic analyses for optimal choice of target therapy for patients with cancer is becoming increasingly complex. A molecular tumor board (MTB) supports oncologists in rationalizing therapy options. However, there is no consensus on the most optimal setup for an MTB, which can affect the quality of recommendations. This study reveals that the eight MTBs associated with tertiary cancer referral centers in The Netherlands are similar in setup and reach a high agreement in recommendations for rare or complex mutational profiles. The Dutch MTB model is based on a collaborative and nationally aligned workflow with interinstitutional collaboration and data sharing., Worldwide, molecular tumor boards (MTBs) differ in terms of scope, composition, methods, and recommendations. This article assesses differences in methods and agreement in treatment recommendations among MTBs from tertiary cancer referral centers in The Netherlands.

A functional version of the Kato one-parametric regularisation for the construction of a dynamical semigroup generator of a relative bound one perturbation is introduced. It does not require that the minus generator of the unperturbed semigroup is a positivity preserving operator. The regularisation is illustrated by an example of a boson-number cut-off regularisation.

Для построения генератора динамической полугруппы в случае возмущений с относительной гранью, равной единице, вводится функциональный вариант однопараметрической регуляризации Като. В качестве примера применения рассмотрена регуляризация, основанная на обрезании числа бозонов.

PURPOSE Molecular tumor boards (MTBs) provide physicians with a treatment recommendation for complex tumor-specific genomic alterations. National and international consensus to reach a recommendation is lacking. In this article, we analyze the effectiveness of an MTB decision-making methodology for patients with non–small-cell lung cancer (NSCLC) with rare or complex mutational profiles as implemented in the University Medical Center Groningen (UMCG). METHODS The UMCG-MTB comprises (pulmonary) oncologists, pathologists, clinical scientists in molecular pathology, and structural biologists. Recommendations are based on reported actionability of variants and molecular interpretation of pathways affected by the variant and supported by molecular modeling. A retrospective analysis of 110 NSCLC cases (representing 106 patients) with suggested treatment of complex genomic alterations and corresponding treatment outcomes for targeted therapy was performed. RESULTS The MTB recommended targeted therapy for 59 of 110 NSCLC cases with complex molecular profiles: 24 within a clinical trial, 15 in accordance with guidelines (on label) and 20 off label. All but 16 recommendations involved patients with an EGFR or ALK mutation. Treatment outcome was analyzed for patients with available follow-up (10 on label and 16 off label). Adherence to the MTB recommendation (21 of 26; 81%) resulted in an objective response rate of 67% (14 of 21), with a median progression-free survival of 6.3 months (interquartile range, 3.2-10.6 months) and an overall survival of 10.4 months (interquartile range, 6.3-14.6 months). CONCLUSION Targeted therapy recommendations resulting from the UMCG-MTB workflow for complex molecular profiles were highly adhered to and resulted in a positive clinical response in the majority of patients with metastatic NSCLC.

BackgroundSince 2015, Dutch guidelines have recommendedBRCA1/2pathogenic variant testing for all patients with epithelial ovarian cancer. Recently, recommendations shifted from germline testing to the tumor-first approach, in which tumor tissue is tested first, and subsequent germline testing is performed only in those withBRCA1/2tumor pathogenic variants or a positive family history. Data on testing rates and on characteristics of patients missing out on testing remain scarce.ObjectiveTo evaluateBRCA1/2testing rates in patients with epithelial ovarian cancer and compare testing rates of germline testing (performed from 2015 until mid-2018) versus tumor-first testing (implemented mid-2018).MethodsA consecutive series of 250 patients diagnosed with epithelial ovarian cancer between 2016 and 2019 was included from the OncoLifeS data-biobank of the University Medical Center Groningen, the Netherlands. Testing rates were analyzed for the overall study population and for germline testing (period I) and tumor-first testing (period II) separately. Characteristics of tested and untested patients were compared and predictors for receiving testing were assessed with multivariable logistic regression.ResultsMedian age was 67.0 years (IQR 59.0–73.0) and 173 (69.2%) patients were diagnosed with high-grade serous carcinoma. Overall, 201 (80.4%) patients were tested. In period I, 137/171 (80.1%) patients were tested and in period II this was 64/79 (81.0%). Patients with non-high-grade serous carcinoma were significantly less likely to receiveBRCA1/2testing than patients with high-grade serous carcinoma (OR=0.23, 95% CI 0.11 to 0.46, pConclusionsThe results show thatBRCA1/2testing rates are suboptimal and suggest that clinicians may not be choosing to test patients with epithelial ovarian cancer with non-high-grade serous ovarian carcinoma, although guidelines recommendBRCA1/2testing in all patients with epithelial ovarian cancer. Suboptimal testing rates limit optimization of care for patients with epithelial ovarian cancer and counseling of potentially affected relatives.

Let $\Omega \subset \mathbb{R}^d$ be a bounded open connected set with Lipschitz boundary. Let $A^N$ and $A^D$ be the Neumann Stokes operator and Dirichlet Stokes operator on $\Omega$, respectively. Further let $\lambda_1^N \leq \lambda_2^N \leq \ldots$ and $\lambda_1^D \leq \lambda_2^D \leq \ldots$ be the eigenvalues of $A^N$ and $A^D$ repeated with multiplicity, respectively. Then \[ \lambda_{n+1}^N < \lambda_n^D \] for all $n \in \mathbb{N}$.

Consider the elliptic operator $$\begin{aligned} A = - \sum _{k,l=1}^d \partial _k \, c_{kl} \, \partial _l + \sum _{k=1}^d a_k \, \partial _k - \sum _{k=1}^d \partial _k \, b_k + a_0 \end{aligned}$$ on a bounded connected open set $$\Omega \subset \mathbb {R}^d$$ with Lipschitz boundary conditions, where $$c_{kl} \in L_\infty (\Omega ,\mathbb {R})$$ and $$a_k,b_k,a_0 \in L_\infty (\Omega ,\mathbb {C})$$ , subject to Robin boundary conditions $$\partial _\nu u + \beta \, {\mathop {\mathrm{Tr \,}}}u = 0$$ , where $$\beta \in L_\infty (\partial \Omega , \mathbb {C})$$ is complex valued. Then we show that the kernel of the semigroup generated by $$-A$$ satisfies Gaussian estimates and Holder Gaussian estimates. If all coefficients and the function $$\beta $$ are real valued, then we prove Gaussian lower bounds. Finally, if $$\Omega $$ is of class $$C^{1+\kappa }$$ with $$\kappa > 0$$ , $$c_{kl} = c_{lk}$$ is Holder continuous, $$a_k = b_k = 0$$ and $$a_0$$ is real valued, then we show that the kernel of the semigroup associated to the Dirichlet-to-Neumann operator corresponding to A has Holder Poisson bounds.

We prove Poisson upper bounds for the heat kernel of the Dirichlet-to-Neumann operator with variable Holder coefficients when the underlying domain is bounded and has a C 1 + κ -boundary for some κ > 0 . We also prove a number of other results such as gradient estimates for heat kernels and Green functions G of elliptic operators with possibly complex-valued coefficients. We establish Holder continuity of ∇ x ∇ y G up to the boundary. These results are used to prove L p -estimates for commutators of Dirichlet-to-Neumann operators on the boundary of C 1 + κ -domains. Such estimates are the keystone in our approach for the Poisson bounds.

The majority of acute myeloid leukemia (AML) patients suffer from relapse and the exact etiology of AML remains unclear. The aim of this study was to gain comprehensive insights into the activity of signaling pathways in AML. In this study, using a high-throughput PepChip™ Kinomics microarray system, pediatric AML samples were analyzed to gain insights of active signal transduction pathway. Unsupervised hierarchical cluster analysis separated the AML blast profiles into two clusters. These two clusters were independent of patient characteristics, whereas the cumulative incidence of relapse (CIR) was significantly higher in the patients belonging to cluster-2. In addition, cluster-2 samples showed to be significantly less sensitive to various chemotherapeutic drugs. The activated peptides in cluster-1 and cluster-2 reflected the activity of cell cycle regulation, cell proliferation, cell differentiation, apoptosis, PI3K/AKT, MAPK, metabolism regulation, transcription factors and GPCRs signaling pathways. The difference between two clusters might be explained by the higher cell cycle arrest response in cluster-1 patients and higher DNA repair mechanism in cluster-2 patients. In conclusion, our study identifies different signaling profiles in pediatric AML in relation with CIR involving DNA damage response and repair.

Consider the Dirichlet problem with respect to an elliptic operator \[ A = - \sum_{k,l=1}^d \partial_k \, a_{kl} \, \partial_l - \sum_{k=1}^d \partial_k \, b_k + \sum_{k=1}^d c_k \, \partial_k + c_0 \] on a bounded Wiener regular open set $\Omega \subset R^d$, where $a_{kl}, c_k \in L_\infty(\Omega,R)$ and $b_k,c_0 \in L_\infty(\Omega,C)$. Suppose that the associated operator on $L_2(\Omega)$ with Dirichlet boundary conditions is invertible. Then we show that for all $\varphi \in C(\partial \Omega)$ there exists a unique $u \in C(\overline \Omega) \cap H^1_{\rm loc}(\Omega)$ such that $u|_{\partial \Omega} = \varphi$ and $A u = 0$. In the case when $\Omega$ has a Lipschitz boundary and $\varphi \in C(\overline \Omega) \cap H^{1/2}(\overline \Omega)$, then we show that $u$ coincides with the variational solution in $H^1(\Omega)$.

Immunotherapy for metastasized non‐small‐cell lung cancer (NSCLC) can show long‐lasting clinical responses. Selection of patients based on programmed death‐ligand 1 (PD‐L1) expression shows limited predictive value for durable clinical benefit (DCB). We investigated whether early treatment effects as measured by a change in circulating tumor DNA (ctDNA) level is a proxy of early tumor response to immunotherapy according to response evaluation criteria in solid tumors v1.1 criteria, progression‐free survival (PFS), DCB, and overall survival (OS). To this aim, blood tubes were collected from advanced‐stage lung adenocarcinoma patients (n = 100) receiving immune checkpoint inhibitors (ICI) at baseline (t0) and prior to first treatment evaluation (4–6 weeks; t1). Nontargetable (driver) mutations detected in the pretreatment tumor biopsy were used to quantify tumor‐specific ctDNA levels using droplet digital PCR. We found that changes in ctDNA levels were strongly associated with tumor response. A > 30% decrease in ctDNA at t1 correlated with a longer PFS and OS. In total, 80% of patients with a DCB of ≥ 26 weeks displayed a > 30% decrease in ctDNA levels. For patients with a PD‐L1 tumor proportion score of ≥ 1%, decreasing ctDNA levels were associated with a higher frequency a DCB (80%) and a prolonged median PFS (85 weeks) and OS (101 weeks) compared with patients with no decrease in ctDNA (34%; 11 and 39 weeks, respectively). This study shows that monitoring of ctDNA dynamics is an easy‐to‐use and promising tool for assessing PFS, DCB, and OS for ICI‐treated NSCLC patients., Predictive markers to reliably monitor response in patients with lung adenocarcinoma treated with immune checkpoint inhibitors are currently lacking. Here, we show that tumor‐informed monitoring of a single bloodborne mutation using droplet digital PCR enabled the identification of early disease progression and durable treatment responses. The association between patient survival and changes in mutant circulating tumor DNA (ctDNA) levels was unrelated to programmed death‐ligand 1 expression. Altogether, our data show that ctDNA dynamics could offer a promising cost‐effective approach to monitor patients with metastasized lung adenocarcinoma.

INTRODUCTION: Non-small cell lung cancer (NSCLC) patients with Anaplastic Lymphoma Kinase (ALK) gene fusions respond well to ALK inhibitors but commonly develop on-target resistance mutations. The objective of this study is to collect clinical evidence for subsequent treatment with ALK inhibitors.PATIENTS AND METHODS: Local experience with on-target ALK resistance mutations and review of the literature identified 387 patients with ALK inhibitor resistance mutations. Clinical benefit of mutation-inhibitor combinations was assessed based on reported response, progression-free survival and duration of treatment. Furthermore, this clinical evidence was compared to previously reported in vitro sensitivity of mutations to the inhibitors.RESULTS: Of the pooled population of 387 patients in this analysis, 239 (62%) received at least 1 additional line of ALK inhibition after developing on-target resistance to ALK inhibitor therapy. Clinical benefit was reported for 177 (68%) patients, but differed for each mutation-inhibitor combination. Agreement between in vitro predicted sensitivity of 6 published models and observed clinical benefit ranged from 64% to 87%. The observed clinical evidence for highest probability of response in the context of specific on-target ALK inhibitor resistance mutations is presented.CONCLUSION: Molecular diagnostics performed on tissue samples that are refractive to ALK inhibitor therapy can reveal new options for targeted therapy for NSCLC patients. Our comprehensive overview of clinical evidence of drug actionability of ALK on-target resistance mechanisms may serve as a practical guide to select the most optimal drug for individual patients.

Background The clinical relevance of epidermal growth factor receptor (EGFR) copy number gain in patients with EGFR mutated advanced non-small cell lung cancer on first-line tyrosine kinase inhibitor treatment has not been fully elucidated. Objective We aimed to estimate EGFR copy number gain using amplicon-based next generation sequencing data and explored its prognostic value. Patients and Methods Next generation sequencing data were obtained for 1566 patients with non-small cell lung cancer. EGFR copy number gain was defined based on an increase in EGFR read counts relative to internal reference amplicons and normal controls in combination with a modified z-score ≥ 3.5. Clinical follow-up data were available for 60 patients treated with first-line EGFR-tyrosine kinase inhibitors. Results Specificity and sensitivity of next generation sequencing-based EGFR copy number estimations were above 90%. EGFR copy number gain was observed in 27.9% of EGFR mutant cases and in 7.4% of EGFR wild-type cases. EGFR gain was not associated with progression-free survival but showed a significant effect on overall survival with an adjusted hazard ratio of 3.14 (95% confidence interval 1.46–6.78, p = 0.003). Besides EGFR copy number gain, osimertinib in second or subsequent lines of treatment and the presence of T790M at relapse revealed significant effects in a multivariate analysis with adjusted hazard ratio of 0.43 (95% confidence interval 0.20–0.91, p = 0.028) and 0.24 (95% confidence interval 0.1–0.59, p = 0.001), respectively. Conclusions Pre-treatment EGFR copy number gain determined by amplicon-based next generation sequencing data predicts worse overall survival in EGFR-mutated patients treated with first-line EGFR-tyrosine kinase inhibitors. T790M at relapse and subsequent treatment with osimertinib predict longer overall survival. Supplementary Information The online version contains supplementary material available at 10.1007/s11523-021-00798-2.

In this chapter we describe implementation details of some of the Unreal Engine 4 ray tracing effects that shipped in Fortnite Season 15. In particular, we dive deeply into ray traced reflections and global illumination. This includes goals, practical considerations, challenges, and optimization techniques.

Circulating cell-free DNA (ccfDNA) may contain DNA originating from the tumor in plasma of cancer patients (ctDNA) and enables noninvasive cancer diagnosis, treatment predictive testing, and response monitoring. A recent multicenter evaluation of workflows by the CANCER-ID consortium using artificial spiked-in plasma showed significant differences and consequently the importance of carefully selecting ccfDNA extraction methods. Here, the quantity and integrity of extracted ccfDNA from the plasma of cancer patients were assessed. Twenty-one cancer patient-derived cell-free plasma samples were selected to compare the Qiagen CNA, Maxwell RSC ccfDNA plasma, and Zymo manual quick ccfDNA kit. High-volume citrate plasma samples collected by diagnostic leukapheresis from six cancer patients were used to compare the Qiagen CNA (2 mL) and QIAamp MinElute ccfDNA kit (8 mL). This study revealed similar integrity and similar levels of amplified short-sized fragments and tumor-specific mutants comparing the CNA and RSC kits. However, the CNA kit consistently showed the highest yield of ccfDNA and short-sized fragments, while the RSC and ME kits showed higher variant allelic frequencies (VAFs). Our study pinpoints the importance of standardizing preanalytical conditions as well as consensus on defining the input of ccfDNA to accurately detect ctDNA and be able to compare results in a clinical routine practice, within and between clinical studies.

Let $\Omega$ be a bounded domain in R d with Lipschitz boundary $\Gamma$. We define the Dirichlet-to-Neumann operator N on L 2 ($\Gamma$) associated with a second order elliptic operator A = -- d k,j=1 $\partial$ k (c kl $\partial$ l) + d k=1 b k $\partial$ k -- $\partial$ k (c k $\times$) + a 0. We prove a criterion for invariance of a closed convex set under the action of the semigroup of N. Roughly speaking, it says that if the semigroup generated by --A, endowed with Neumann boundary conditions, leaves invariant a closed convex set of L 2 ($\Omega$), then the 'trace' of this convex set is invariant for the semigroup of N. We use this invariance to prove a criterion for the domination of semigroups of two Dirichlet-to-Neumann operators. We apply this criterion to prove the diamagnetic inequality for such operators on L 2 ($\Gamma$).

Background Sensitive and reliable molecular diagnostics is needed to guide therapeutic decisions for cancer patients. Although less material becomes available for testing, genetic markers are rapidly expanding. Simultaneous detection of predictive markers, including mutations, gene amplifications and MSI, will save valuable material, time and costs. Methods Using a single-molecule molecular inversion probe (smMIP)-based targeted next-generation sequencing (NGS) approach, we developed an NGS panel allowing detection of predictive mutations in 33 genes, gene amplifications of 13 genes and microsatellite instability (MSI) by the evaluation of 55 microsatellite markers. The panel was designed to target all clinically relevant single and multiple nucleotide mutations in routinely available lung cancer, colorectal cancer, melanoma, and gastro-intestinal stromal tumor samples, but is useful for a broader set of tumor types. Results The smMIP-based NGS panel was successfully validated and cut-off values were established for reliable gene amplification analysis (i.e. relative coverage ≥3) and MSI detection (≥30% unstable loci). After validation, 728 routine diagnostic tumor samples including a broad range of tumor types were sequenced with sufficient sensitivity (2.4% drop-out), including samples with low DNA input (EGFR, BRAF, MET, ERBB2, KIT, PDGFRA). Amplifications were observed in 5.5% of the samples, comprising clinically relevant amplifications (e.g. MET, ERBB2, FGFR1). 1.5% of the tumor samples were classified as MSI-high, including both MSI-prone and non-MSI-prone tumors. Conclusions We developed a comprehensive workflow for predictive analysis of diagnostic tumor samples. The smMIP-based NGS analysis was shown suitable for limited amounts of histological and cytological material. As smMIP technology allows easy adaptation of panels, this approach can comply with the rapidly expanding molecular markers.

We present a way of defining the Dirichlet-to-Neumann operator on general Hilbert spaces using a pair of operators for which each one's adjoint is formally the negative of the other. In particular, we define an abstract analogue of trace spaces and are able to give meaning to the Dirichlet-to-Neumann operator of divergence form operators perturbed by a bounded potential in cases where the boundary of the underlying domain does not allow for a well-defined trace. Moreover, a representation of the Dirichlet-to-Neumann operator as a first-order system of partial differential operators is provided. Using this representation, we address convergence of the Dirichlet-to-Neumann operators in the case that the appropriate reciprocals of the leading coefficients converge in the weak operator topology. We also provide some extensions to the case where the bounded potential is not coercive and consider resolvent convergence., 31 pages, some referee's remarks included. Example 4.3 added. Example 6.1 now contains a characterisation instead of merely an implication. Example 6.7 is new and gives a characterisation for the condition in Theorem 4.2 in the `classical case'. Remark 6.8 is new and explains that weak* convergence is independent of the conditions in Example 6.7