Stratifying esophago-gastric cancer treatment using a patient-derived organoid-based threshold.

BACKGROUND AND AIMS: This study sought to determine the value of patient-derived organoids (PDOs) from esophago-gastric adenocarcinoma (EGC) for response prediction to neoadjuvant chemotherapy (neoCTx). METHODS: Endoscopic biopsies of patients with locally advanced EGC (n = 120) were taken into culture and PDOs expanded. PDOs' response towards the single substances of the FLOT regimen and the combination treatment were correlated to patients' pathological response using tumor regression grading. A classifier based on FLOT response of PDOs was established in an exploratory cohort (n = 13) and subsequently confirmed in an independent validation cohort (n = 13). RESULTS: EGC PDOs reflected patients' diverse responses to single chemotherapeutics and the combination regimen FLOT. In the exploratory cohort, PDOs response to single 5-FU and FLOT combination treatment correlated with the patients' pathological response (5-FU: Kendall's τ = 0.411, P = 0.001; FLOT: Kendall's τ = 0.694, P = 2.541e-08). For FLOT testing, a high diagnostic precision in receiver operating characteristic (ROC) analysis was reached with an AUCROC of 0.994 (CI 0.980 to 1.000). The discriminative ability of PDO-based FLOT testing allowed the definition of a threshold, which classified in an independent validation cohort FLOT responders from non-responders with high sensitivity (90%), specificity (100%) and accuracy (92%). CONCLUSION: In vitro drug testing of EGC PDOs has a high predictive accuracy in classifying patients' histological response to neoadjuvant FLOT treatment. Taking into account the high rate of successful PDO expansion from biopsies, the definition of a threshold that allows treatment stratification paves the way for an interventional trial exploring PDO-guided treatment of EGC patients.

SNP array genomic analysis of matched pairs of brain and liver metastases in primary colorectal cancer.

PURPOSE: Brain metastasis formation is a rare and late event in colorectal cancer (CRC) patients and associated with poor survival. In contrast to other metastatic sites, the knowledge on chromosomal aberrations in brain metastases is very limited. METHODS: Therefore, we carried out single nucleotide polymorphism (SNP) array analyses on matched primary CRC and brain metastases of four patients as well as on liver metastases of three patients. RESULTS: Brain metastases showed more chromosomal aberrations than primary tumors or liver metastases. Commonly occurring aberrations were gain of 8q11.1-q24.3 (primary CRC), gain of 13q12.13-q12.3 (liver metastases), and gain of 20q11.1-q13.33 (brain metastases). Furthermore, we found one copy-neutral loss of heterozygosity (cn-LOH) region on chromosome 3 in primary CRC, three cn-LOH regions in liver metastases and 23 cn-LOH regions in brain metastases, comprising 26 previously undescribed sites. CONCLUSION: The more frequent occurrence of cn-LOHs and subsequently affected genes in brain metastases shed light on the pathophysiology of brain metastasis formation. Further pairwise genetic analyses between primary tumors and their metastases will help to define the role of affected genes in cn-LOH regions.

Analysis of an Unselected Patient Cohort With Advanced Colorectal Carcinoma from a Maximum Care Center.

BACKGROUND/AIM: Systemic treatment for metastatic colorectal cancer (CRC) includes chemotherapy in combination with a targeted antibody. Novel targeted therapies and immunotherapies are introduced for specific molecular subgroups. Prognostic relevant determinants are still under investigation. PATIENTS AND METHODS: Systemic therapies of an unselected patient cohort with metastatic CRC were retrospectively analyzed. Treatment outcome was evaluated according to time-to-next-treatment (TTNT) and frequency of conversion surgery and compared between subgroups stratified by primary tumor side, molecular profile, sex and age, and metastases sites. RESULTS: More than 50% of patients with locally advanced or metastatic CRC underwent secondary resection after first-line systemic therapy. Rectum carcinoma had the best prognosis under anti-EGFR-antibody treatment. Female patients had a worse prognosis than male patients in late disease stage. Young patients demonstrated poor response to systemic therapy, but a high rate of conversion surgeries. Conversely, elderly patients benefited from systemic therapy but underwent surgery less frequently. Liver and lung metastases had a worse prognosis than other metastases sites, whereas lung metastases were more likely to be resected than liver metastases in early disease stage. CONCLUSION: Patient age, sex, primary tumor localization, and metastatic sites are prognostic factors that could guide future treatment decisions for the therapy of metastatic CRC.

A microbiota-modulated checkpoint directs immunosuppressive intestinal T cells into cancers.

Antibiotics (ABX) compromise the efficacy of programmed cell death protein 1 (PD-1) blockade in cancer patients, but the mechanisms underlying their immunosuppressive effects remain unknown. By inducing the down-regulation of mucosal addressin cell adhesion molecule 1 (MAdCAM-1) in the ileum, post-ABX gut recolonization by Enterocloster species drove the emigration of enterotropic α4ß7+CD4+ regulatory T 17 cells into the tumor. These deleterious ABX effects were mimicked by oral gavage of Enterocloster species, by genetic deficiency, or by antibody-mediated neutralization of MAdCAM-1 and its receptor, α4ß7 integrin. By contrast, fecal microbiota transplantation or interleukin-17A neutralization prevented ABX-induced immunosuppression. In independent lung, kidney, and bladder cancer patient cohorts, low serum levels of soluble MAdCAM-1 had a negative prognostic impact. Thus, the MAdCAM-1-α4ß7 axis constitutes an actionable gut immune checkpoint in cancer immunosurveillance.

Endoscopic Stent Placement Can Successfully Treat Gastric Leak Following Laparoscopic Sleeve Gastrectomy If and Only If an Esophagoduodenal Megastent Is Used.

PURPOSE: Gastric staple line leakage (GL) is a serious complication of laparoscopic sleeve gastrectomy (LSG), with a specific mortality ranging from 0.2 to 3.7%. The current treatment of choice is stent insertion. However, it is unclear whether the type of stent which is inserted affects treatment outcome. Therefore, we aimed not only to determine the effectiveness of stent treatment for GL but also to specifically clarify whether treatment outcome was dependent on the type of stent (small- (SS) or megastent (MS)) which was used. PATIENTS AND METHODS: A single-centre retrospective study of 23 consecutive patients was conducted to compare the outcomes of SS (n = 12) and MS (n = 11) for the treatment of GL following LSG. The primary outcome measure was the success rate of stenting, defined as complete healing of the GL without changing the treatment strategy. Treatment change or death were both coded as failure. RESULTS: The success rate of MS was 91% (10/11) compared to only 50% (6/12) for SS (p = 0.006). An average of 2.3 ± 0.5 and 6.8 ± 3.7 endoscopies were required to achieve healing in the MS and SS groups respectively (p < 0.001). The average time to resumption of oral nutrition was shorter in the MS group (1.4 ± 1.1 days vs. 23.1 ± 33.1 days, p = 0.003). CONCLUSIONS: Stent therapy is only effective and safe for the treatment of GL after LSG if a MS is used. Treatment with a MS may not only increase treatment success rates but may also facilitate earlier resumption of oral nutrition and shorten the duration of hospitalization.

Feasibility, effectiveness, and safety of endoscopic vacuum therapy for intrathoracic anastomotic leakage following transthoracic esophageal resection.

BACKGROUND: Anastomotic leakage (AL) in the upper gastrointestinal (GI) tract is associated with high morbidity and mortality rates. Especially intrathoracic anastomotic leakage leads to life-threatening complications. Endoscopic vacuum therapy (EVT) for anastomotic leakage after transthoracic esophageal resection represents a novel concept. However, sound clinical data are still scarce. This retrospective, single-center study aimed to evaluate the feasibility, effectiveness, and safety of EVT for intrathoracic anastomotic leakage following abdomino-thoracic esophageal resection. METHODS: From March 2014 to September 2019 259 consecutive patients underwent elective transthoracic esophageal resection. 72 patients (27.8%) suffered from AL. The overall collective in-hospital mortality rate was 3.9% (n = 10). Data from those who underwent treatment with EVT were included. RESULTS: Fifty-five patients were treated with EVT. Successful closure was achieved in 89.1% (n = 49) by EVT only. The EVT-associated complication rate was 5.4% (n = 3): bleeding occurred in one patient, while minor sedation-related complications were observed in two patients. The median number of EVT procedures per patient was 3. The procedures were performed at intervals of 3-5 days, with a 14-day median duration of therapy. The mortality rate of patients with AL was 7.2% (n = 4). Despite successfully terminated EVT, three patients died because of multiple organ failure, acute respiratory distress syndrome, and urosepsis (5.4%). One patient (1.8%) died during EVT due to cardiac arrest. CONCLUSIONS: EVT is a safe and effective approach for intrathoracic anastomotic leakages following abdomino-thoracic esophageal resections. It offers a high leakage-closure rate and the potential to lower leakage-related mortalities. TRIAL REGISTRATION: This trial was registered and approved by the Institutional Ethics Committee of the University of Heidelberg on 16.04.2014 (Registration Number: S-635/2013).

Percutaneous Endoscopic Gastrostomy Tube Placement in Patients with Head and Neck Cancer Treated with Radiotherapy.

BACKGROUND AND AIM: The primary aim of our study was to evaluate percutaneous endoscopic gastrostomy (PEG) tube placement depending on body weight and body mass index in patients undergoing radiotherapy (RT) for head and neck cancer (HNC). A secondary aim was to evaluate the course of weight change following PEG placement. METHODS: We retrospectively reviewed the medical records of 186 patients with HNC undergoing radiotherapy (RT) or chemoradiotherapy (CRT) at our institution between January 2010 and August 2017. Initial weight and nutritional intake were analyzed prior to RT initiation and then followed throughout treatment until completion. Based on these data, the indication of PEG placement was determined. Medical records were also reviewed to analyze PEG-related acute toxicities. RESULTS: A total of 186 patients met inclusion criteria. Patients were most commonly male (n=123, 66.1%) with squamous cell carcinoma (n=164, 88.2%). Patients who had dysphagia prior to treatment initiation as well as patients with a BMI <18.5 kg/m2 needed PEG placement earlier during the treatment course. Low-grade toxicities related to PEG insertion were observed in 10.7% patients, with peristomal pain and redness adjacent to the PEG tube insertion site being most common. High-grade toxicities, such as peritonitis and organ injury, were found in 4.9% of patients. CONCLUSION: Underweight patients and those with preexisting dysphagia should be closely screened during RT for weight loss and decreased oral intake. For weight loss greater than 4.5% during the treatment of HNC, early PEG-tube placement should be considered. Further prospective studies are needed to confirm these findings, and delineate a scoring system for timing of PEG use (prophylactic vs reactive) as well as assess the quality of life in patients with HNC who receive PEG placement.

Molecular characterization of hepatic epithelioid hemangioendothelioma reveals alterations in various genes involved in DNA repair, epigenetic regulation, signaling pathways, and cell cycle control.

Epithelioid hemangioendotheliomas (EHE) of the liver are rare, low-malignant vascular tumors whose molecular pathogenesis is incompletely understood. The diagnosis of EHE is challenging, and the course of the disease can be highly variable. Therapeutic options for EHE are limited, including resection of primary and metastatic tumors, organ transplantation and rather ineffective systemic approaches. Driver mutations have been reported (fusion transcripts of either YAP-TFE3 or WWTR1-CAMTA1) but comprehensive molecular profiling has not been performed. Our aim was to molecularly characterize hepatic EHE to identify new molecular targets. Eight primary hepatic EHE were analyzed by next-generation sequencing using a 409-gene panel. The majority of primary hepatic EHE revealed a low number of mutations. Genes that were mutated primarily are involved in DNA repair, epigenetic regulation, signaling pathways and cell cycle control, indicating that EHE present with mutations in various functions. Although only detecting a low mutation rate, a comparison with comprehensive databases (target db V3) revealed mutations in five genes with putative therapeutical options. Therefore, our findings help to shed light on the molecular background of EHE and might pave the way to new therapeutic approaches.

Tumor response to irinotecan is associated with CYP3A5 expression in colorectal cancer.

Recently, a tumor-autonomous cytochrome P450 (CYP)-3A5-mediated resistance to cancer therapy has been demonstrated in pancreatic ductal adenocarcinoma. Expression of CYP3A5, which is involved in the degradation of irinotecan, has also been reported in colorectal cancer (CRC). The aim of the present study was to analyze CYP3A5 expression in the normal colon, colon adenoma, CRC and normal tissues, as well as to examine whether CYP3A5 expression in CRC has an impact on tumor response to irinotecan treatment. Immunohistochemistry was used to assess 85 tissue samples from 65 patients with CRC, along with 15 samples of normal colon and 45 samples of colon adenoma (including tubular, tubulovillous, and sessile serrated adenomas), and a tissue microarray (TMA) comprised of 26 different normal tissue types. Expression of CYP3A5 was evaluated with a semi-quantitative score. Tumor response to irinotecan therapy was assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 guidelines. In normal tissues, CYP3A5 was expressed in epithelial cells of the colon, gallbladder, kidney, liver, small intestine, stomach, thyroid gland and tonsil, as well as in nerves. Expression in colon mucosa was heterogeneous, with only weak staining in the minority of specimens. CYP3A5 exhibited markedly higher expression in adenomas compared with normal colon tissues. A statistically significant inverse correlation was identified between CYP3A5 expression in CRC tissues and tumor response to irinotecan therapy. Irinotecan treatment itself did not alter CYP3A5 expression in CRC tissues. As CYP3A5 is involved in the degradation of irinotecan, the significantly higher intratumoral expression of CYP3A5 in patients with CRC who do not respond to irinotecan-based chemotherapy may indicate a causal role of CYP3A5 in tumor resistance.

Case report: a rare cause of a hypervascular nodule in a noncirrhotic liver.

A 37-year-old male patient with Crohn's disease and multiple liver hemangiomas was referred to our hospital for an atypical hypervascular hepatic lesion detected on an external magnetic resonance imaging (MRI) scan. The patient was otherwise well and had no history of any liver disease. Liver values and tumor markers were normal. Contrast-enhanced ultrasound confirmed multiple hemangiomas in different liver segments and a hypervascular tumor with a hypovascular rim in segment II/IV. Repeat MRI showed a strongly enhancing neoplasm of 2.6 cm with a texture distinctly different from the otherwise relatively uniform hemangiomas, without evidence of interim growth. Ultrasound-guided biopsy revealed a hepatic small vessel neoplasm. Due to the unknown malignant potential, atypical segmental surgical resection was performed. Final histopathological analysis confirmed the complete resection of the lesion. The postoperative course was uneventful.

Secretion of Hepatitis C Virus Replication Intermediates Reduces Activation of Toll-Like Receptor 3 in Hepatocytes.

BACKGROUND & AIMS: Hepatitis C virus (HCV) infections most often result in chronic outcomes, although the virus constantly produces replication intermediates, in particular double-stranded RNA (dsRNA), representing potent inducers of innate immunity. We aimed to characterize the fate of HCV dsRNA in hepatocyte cultures to identify mechanisms contributing to viral persistence in presence of an active innate immune response. METHODS: We analyzed hepatocyte-based culture models for HCV for induction of innate immunity, secretion of virus positive- or negative-strand RNA, and viral replication using different quantification methods and microscopy techniques. Expression of pattern recognition receptors was reconstituted in hepatoma cells by lentiviral transduction. RESULTS: HCV-infected cells secrete substantial amounts of virus positive- and negative-strand RNAs in extracellular vesicles (EVs), toward the apical and basolateral domain of hepatocytes. Secretion of negative-strand RNA was independent from virus production, and viral RNA secreted in EVs contained higher relative amounts of negative-strands, indicating that mostly virus dsRNA is released. A substantial part of viral replication complexes and dsRNA was found in the endosomal compartment and multivesicular bodies, indicating that secretion of HCV replication intermediates is mediated by the exosomal pathway. Block of vesicle release in HCV-positive cells increased intracellular dsRNA levels and increased activation of toll-like receptor 3, inhibiting HCV replication. CONCLUSIONS: Using hepatocyte-based culture models for HCV, we found a portion of HCV dsRNA intermediates to be released from infected cells in EVs, which reduces activation of toll-like receptor 3. This represents a novel mechanism how HCV evades host immune responses, potentially contributing to viral persistence.

HBV Bypasses the Innate Immune Response and Does Not Protect HCV From Antiviral Activity of Interferon.

BACKGROUND & AIMS: Hepatitis C virus (HCV) infection is sensitive to interferon (IFN)-based therapy, whereas hepatitis B virus (HBV) infection is not. It is unclear whether HBV escapes detection by the IFN-mediated immune response or actively suppresses it. Moreover, little is known on how HBV and HCV influence each other in coinfected cells. We investigated interactions between HBV and the IFN-mediated immune response using HepaRG cells and primary human hepatocytes (PHHs). We analyzed the effects of HBV on HCV replication, and vice versa, at the single-cell level. METHODS: PHHs were isolated from liver resection tissues from HBV-, HCV-, and human immunodeficiency virus-negative patients. Differentiated HepaRG cells overexpressing the HBV receptor sodium taurocholate cotransporting polypeptide (dHepaRGNTCP) and PHHs were infected with HBV. Huh7.5 cells were transfected with circular HBV DNA genomes resembling viral covalently closed circular DNA (cccDNA), and subsequently infected with HCV; this served as a model of HBV and HCV coinfection. Cells were incubated with IFN inducers, or IFNs, and antiviral response and viral replication were analyzed by immune fluorescence, reverse-transcription quantitative polymerase chain reaction, enzyme-linked immunosorbent assays, and flow cytometry. RESULTS: HBV infection of dHepaRGNTCP cells and PHHs neither activated nor inhibited signaling via pattern recognition receptors. Incubation of dHepaRGNTCP cells and PHHs with IFN had little effect on HBV replication or levels of cccDNA. HBV infection of these cells did not inhibit JAK-STAT signaling or up-regulation of IFN-stimulated genes. In coinfected cells, HBV did not prevent IFN-induced suppression of HCV replication. CONCLUSIONS: In dHepaRGNTCP cells and PHHs, HBV evades the induction of IFN and IFN-induced antiviral effects. HBV infection does not rescue HCV from the IFN-mediated response.

Sorafenib in Patients with Hepatocellular Carcinoma-Results of the Observational INSIGHT Study.

Purpose: Sorafenib is the only currently approved systemic therapy for advanced hepatocellular carcinoma (HCC). We aimed to evaluate the safety and efficacy of sorafenib therapy in patients with HCC under real-life conditions regarding patient, tumor characteristics, and any adverse events at study entry and at follow-up visits every 2 to 4 months.Experimental Design: The current INSIGHT study is a noninterventional, prospective, multicenter, observational study performed in 124 sites across Austria and Germany between 2008 and 2014.Results: Median overall survival and time to progression (RECIST) were found to be dependent on baseline Barcelona Clinic Liver Cancer (BCLC) tumor stage (A: 29.2, B: 19.6, C: 13.6, D: 3.1 and A: 6.0, B: 5.5, C: 3.9, and D: 1.7 months, respectively), Child-Pugh liver function (A: 17.6, B: 8.1, C: 5.6 and A: 5.3, B: 3.3, C: 2.5 months, respectively), and performance status of the patient; however, age did not affect prognosis. Sorafenib-related adverse events at any grade occurred in 64.9% of patients, with diarrhea (35.4%), hand-foot-skin reaction (16.6%), nausea (10.3%), and fatigue (11.2%) occurring most frequently.Conclusions: Sorafenib treatment was shown to be effective in a real-life setting, in agreement with previously reported clinical trial data. The therapy was found to have an acceptable safety profile, with predominantly mild to moderate side effects. Clin Cancer Res; 23(19); 5720-8. ©2017 AACR.

Cancer cell-autonomous TRAIL-R signaling promotes KRAS-driven cancer progression, invasion, and metastasis.

Many cancers harbor oncogenic mutations of KRAS. Effectors mediating cancer progression, invasion, and metastasis in KRAS-mutated cancers are only incompletely understood. Here we identify cancer cell-expressed murine TRAIL-R, whose main function ascribed so far has been the induction of apoptosis as a crucial mediator of KRAS-driven cancer progression, invasion, and metastasis and in vivo Rac-1 activation. Cancer cell-restricted genetic ablation of murine TRAIL-R in autochthonous KRAS-driven models of non-small-cell lung cancer (NSCLC) and pancreatic ductal adenocarcinoma (PDAC) reduces tumor growth, blunts metastasis, and prolongs survival by inhibiting cancer cell-autonomous migration, proliferation, and invasion. Consistent with this, high TRAIL-R2 expression correlates with invasion of human PDAC into lymph vessels and with shortened metastasis-free survival of KRAS-mutated colorectal cancer patients.

Pancreatic Atrophy in Hepatocellular Carcinoma Patients Receiving Long-Term Treatment with Sorafenib.

OBJECTIVE: To date, sorafenib is the only approved systemic therapy for advanced hepatocellular carcinoma (HCC). Pancreatic atrophy has recently been reported in 2 patients as a novel side effect after long-term sorafenib treatment. METHODS: We retrospectively analyzed clinical and radiological data of patients with advanced HCC with long-term treatment of sorafenib (median 279 days, range 153-826 days). Pancreata were semi-manually segmented section by section to calculate the pancreas volumes before and under sorafenib treatment. RESULTS: Sorafenib reduced pancreatic volume in 18/19 (95%) HCC patients with a mean pancreatic volume loss of 25% (p = 0.002). Pancreatic volume loss depended on the dose (r = 0.36) and exposure time of sorafenib (r = 0.35) and was detectable as early as after 3 months of sorafenib treatment and already after a cumulative sorafenib dose of <100 g. Median overall survival was 13.2 months (range 7.8-31.3 months) but did not correlate with sorafenib-induced pancreatic volume reduction (hazard ratio 1.002, 95% confidence interval 0.981-1.060, p = 0.24). CONCLUSION: We could confirm pancreatic atrophy as a novel adverse event of sorafenib therapy in HCC patients, correlating with sorafenib dose and exposure time.

Three gangliogliomas: results of GTG-banding, SKY, genome-wide high resolution SNP-array, gene expression and review of the literature.

According to the World Health Organization gangliogliomas are classified as well-differentiated and slowly growing neuroepithelial tumors, composed of neoplastic mature ganglion and glial cells. It is the most frequent tumor entity observed in patients with long-term epilepsy. Comprehensive cytogenetic and molecular cytogenetic data including high-resolution genomic profiling (single nucleotide polymorphism (SNP)-array) of gangliogliomas are scarce but necessary for a better oncological understanding of this tumor entity. For a detailed characterization at the single cell and cell population levels, we analyzed genomic alterations of three gangliogliomas using trypsin-Giemsa banding (GTG-banding) and by spectral karyotyping (SKY) in combination with SNP-array and gene expression array experiments. By GTG and SKY, we could confirm frequently detected chromosomal aberrations (losses within chromosomes 10, 13 and 22; gains within chromosomes 5, 7, 8 and 12), and identify so far unknown genetic aberrations like the unbalanced non-reciprocal translocation t(1;18)(q21;q21). Interestingly, we report on the second so far detected ganglioglioma with ring chromosome 1. Analyses of SNP-array data from two of the tumors and respective germline DNA (peripheral blood) identified few small gains and losses and a number of copy-neutral regions with loss of heterozygosity (LOH) in germline and in tumor tissue. In comparison to germline DNA, tumor tissues did not show substantial regions with significant loss or gain or with newly developed LOH. Gene expression analyses of tumor-specific genes revealed similarities in the profile of the analyzed samples regarding different relevant pathways. Taken together, we describe overlapping but also distinct and novel genetic aberrations of three gangliogliomas.

WHO grade related expression of TRAIL-receptors and apoptosis regulators in meningioma.

BACKGROUND AND AIMS: The expression of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptors and key regulators of the extrinsic apoptosis pathway correlate with clinical features and the WHO grade of malignancy in some tumor entities. Expression of pro-apoptotic TRAIL receptors and executioners of apoptosis are a prerequisite for TRAIL-based therapies as a promising future targeted therapy. METHODS: Human meningioma tissues (n=24 WHO grade I, n=7 WHO grade II, n=6 WHO grade III) were immunohistochemically analyzed for the expression of TRAIL-R1, TRAIL-R2, TRAIL-R3, TRAIL-R4, caspase-8, cFLIP, Bcl-2, Bcl-XL, Mcl-1, Bax, and Bak. Staining intensities were quantified by an automated software-based algorithm. RESULTS: While TRAIL-R1 and TRAIL-R3 were nearly absent in meningiomas, TRAIL-R2 and TRAIL-R4 were abundantly expressed. However, only TRAIL-R4 expression correlated with the WHO grade of malignancy. Bcl-2 showed a non-significant upregulation in WHO grade III meningiomas. Bcl-XL and Mcl-1 expression was significantly higher in WHO grade II compared to grade I. Bcl-XL and TRAIL-R4 expression correlated with the mitotic activity (Ki67) of the tumor. Furthermore, TRAIL-R2 expression correlated with TRAIL-R4. Bak expression correlated with both, Bcl-XL and Mcl-1 expression. The expression patterns did neither correlate with the progression-free nor with the overall survival of the meningioma patients. CONCLUSIONS: Apoptosis-inducing TRAIL-R2 and all key executioners of the extrinsic apoptosis pathway are abundantly expressed in meningioma. For some regulators of apoptosis with opposite functions, the expression of the pro-apoptotic protein significantly correlated with the expression level of the respective anti-apoptotic binding partner, possibly resulting in a steady-state of apoptosis. TRAIL-R2 might serve as a novel therapeutic target in meningioma.

Bortezomib sensitizes primary meningioma cells to TRAIL-induced apoptosis by enhancing formation of the death-inducing signaling complex.

A meningioma is the most common primary intracranial tumor in adults. Here, we investigated the therapeutic potential of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in 37 meningiomas. Freshly isolated primary meningioma cells were treated with TRAIL with or without different sensitizing protocols, and apoptotic cell death was then quantified. Mechanisms of TRAIL sensitization were determined by a combination of Western blotting, flow cytometry, receptor complex immunoprecipitation, and siRNA-mediated knockdown experiments. Tumor necrosis factor-related apoptosis-inducing ligand receptor expression was analyzed using immunohistochemistry and quantified by an automated software-based algorithm. Primary tumor cells from 11 (29.7%) tumor samples were sensitive to TRAIL-induced apoptosis, 12 (32.4%) were intermediate TRAIL resistant, and 14 (37.8%) were completely TRAIL resistant. We tested synergistic apoptosis-inducing cotreatment strategies and determined that only the proteasome inhibitor bortezomib potently enhanced expression of the TRAIL receptors TRAIL-R1 and/or TRAIL-R2, the formation of the TRAIL death-inducing signaling complex, and activation of caspases; this treatment resulted in sensitization of all TRAIL-resistant meningioma samples to TRAIL-induced apoptosis. Bortezomib pretreatment induced NOXA expression and downregulated c-FLIP, neither of which caused the TRAIL-sensitizing effect. Native TRAIL receptor expression could not predict primary TRAIL sensitivity. This first report on TRAIL sensitivity of primary meningioma cells demonstrates that TRAIL/bortezomib cotreatment may represent a novel therapeutic option for meningiomas.

Human and mouse VEGFA-amplified hepatocellular carcinomas are highly sensitive to sorafenib treatment.

UNLABELLED: Death rates from hepatocellular carcinoma (HCC) are steadily increasing, yet therapeutic options for advanced HCC are limited. We identify a subset of mouse and human HCCs harboring VEGFA genomic amplification, displaying distinct biologic characteristics. Unlike common tumor amplifications, this one seems to work via heterotypic paracrine interactions; stromal VEGF receptors (VEGFR), responding to tumor VEGF-A, produce hepatocyte growth factor (HGF) that reciprocally affects tumor cells. VEGF-A inhibition results in HGF downregulation and reduced proliferation, specifically in amplicon-positive mouse HCCs. Sorafenib-the first-line drug in advanced HCC-targets multiple kinases, including VEGFRs, but has only an overall mild beneficial effect. We found that VEGFA amplification specifies mouse and human HCCs that are distinctly sensitive to sorafenib. FISH analysis of a retrospective patient cohort showed markedly improved survival of sorafenib-treated patients with VEGFA-amplified HCCs, suggesting that VEGFA amplification is a potential biomarker for HCC response to VEGF-A-blocking drugs. SIGNIFICANCE: Using a mouse model of inflammation-driven cancer, we identified a subclass of HCC carrying VEGFA amplification, which is particularly sensitive to VEGF-A inhibition. We found that a similar amplification in human HCC identifies patients who favorably responded to sorafenib-the first-line treatment of advanced HCC-which has an overall moderate therapeutic efficacy.