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INTRODUCTION The true pathology and clinical implication of treatment-related image changes (TRICs) after stereotactic radiosurgery (SRS) for brain metastases (BM) have not been established. This study compared the surgical pathology and outcomes of intracranial metastatic lesions featured as TRICs or progressive disease (PD) in advanced magnetic resonance imaging (MRI).METHODS A total of 86 patients who underwent surgical resection of brain metastases previously treated with gamma knife radiosurgery (GKS) from 2009 to 2019 were retrospectively reviewed and classified by MRI findings and histopathology.RESULTS Among 54 patients with TRICs in preoperative MRI, the histopathology of pure radiation necrosis (RN) was confirmed in 19 patients (TRIC-RN) and mixed or predominant viable tumor cells in 35 patients (TRIC-PD). Thirty-two patients diagnosed with PD exhibited the metastatic histology well correlated with imaging (PD-PD). The TRIC-PD group showed larger prescription isodose volume (9.4 cm3) than the TRIC-RN (4.06 cm3, p=0.014) group and shorter time interval from GKS to preoperative MRI diagnosis related to neurological deficits (median 4.07 months) than the PD-PD group (median 8.77 months, p=0.004). Significant differences in progression-free survival were confirmed among the three groups (pCONCLUSIONS The brain metastatic lesions diagnosed as TRICs after GKS frequently contained viable tumor cells, while they exhibited the benign prognosis as RN after surgical resection. These findings suggest that TRICs on advanced MRI can serve as a prognostic factor, regardless of the histologic heterogeneity.

Background: Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most frequent cause of cancer-related mortality worldwide. The genetic and physiological complexity of HCC is a major barrier to the study of tumorigenesis and identification of therapeutic targets. The three-dimensional (3D) culture of cancer cells within an extracellular matrix (ECM) provides an in vitro tumor model that best recapitulates in vivo tumor pathophysiology.Methods: In the current study, we cultured cells and made spheroids by aggregating cells or diffusing cells in Matrigel attached on the tip of the 96-pillar plate. According to the initial cell position in Matrigel, two 3D-HCC cancer in-vitro models (diffused spheroid model and aggregated spheroid model) were established. These two models were applied to drug sensitivity assays to identify drug sensitivity changes. The protein expression and cytokine activation related to the drug resistance and maintenance of the physiological properties of HCC cells were analyzed in both models. This 3D culture method not only maintained the phenotype of the tumor but allowed easy high-throughput screening (HTS) due to its 96-array plate configuration.Results: The Aggregated Spheroid Model (ASM) showed higher expression of cancer markers associated with proliferation, tight junctions formation and epithelial cell identity in HCC cells, as well as cytokine factors associated with immune cell recruitment/activation, ECM regulation, cancer interaction, and angiogenesis regulation.Conclusions: Overall, the proposed ASM better recapitulates the tumor microenvironment, demonstrating the involvement of the ECM/tight junctions in the cell-to-cell signaling processes. This provides more instructive data for in vitro screening of tumor cells.

Objective The retroinfundibular and upper clival regions are challenging to access using the endoscopic endonasal approach because these regions are obstructed by the dorsum sellae and posterior clinoid processes. We evaluated the safety and clinical efficacy of endoscopic dorsum sellar resection (DSR) and identified the optimal indications for endoscopic DSR in patients with craniopharyngioma. Methods A retrospective study was conducted of patients who had undergone treatment with an endoscopic endonasal approach from January 2014 to January 2019. We identified a total of 50 patients who had undergone DSR. The indications for DSR included the following: 1) a tumor involving the upper clivus; 2) a tumor located behind the dorsum sellae; and 3) a tumor involving the interpeduncular or prepontine cistern. We evaluated the clinical outcomes, postoperative endocrinological status, and surgical morbidities. Results Of the 50 patients, 16 had been treated for craniopharyngioma, 30 for chordoma, 2 for pituitary adenoma, 1 for schwannoma, and 1 for chondrosarcoma. An extradural approach for DSR with posterior clinoidectomy was performed in 33 patients (66.0%) and an interdural transcavernous approach in 17 patients (34.0%). The overall gross total tumor resection rate was 92.0% (46 of 50 patients). Postoperatively, 28 of 33 patients (84.8%) with normal pituitary function preoperatively showed preservation of hormonal function postoperatively. Conclusions DSR with or without posterior clinoidectomy is a challenging procedure that requires considerable effort and advanced surgical techniques. However, it can be safely performed with accumulating experience and a thorough knowledge of the surrounding anatomical structures.

Simple Summary Real-time ex vivo drug testing tailors individual therapeutics based on predicted drug responses. Most technologies to date rely on conventional drug screening that provides low confidence data. Here, we present high-content analysis-based drug testing of glioblastoma patients to identify the right glioblastoma patients for a given drug. This generates multi-parameter biomarker and phenotype readouts providing a better reliability of the assay. Additionally, we showed a high-content drug repurposing screen and defined a new c-Met-inhibiting function of the CDK4/6 inhibitor Abemaciclib. Large-scale high throughput screening results demonstrate that Abemaciclib sensitivity in glioblastoma patients is highly correlated with the c-Met inhibitors sensitivity, further supporting the accuracy of the platform and important new clinical implications regarding multiple functions of Abemaciclib. Abstract (1) Background: Recent advances in precision oncology research rely on indicating specific genetic alterations associated with treatment sensitivity. Developing ex vivo systems to identify cancer patients who will respond to a specific drug remains important. (2) Methods: cells from 12 patients with glioblastoma were isolated, cultured, and subjected to high-content screening. Multi-parameter analyses assessed the c-Met level, cell viability, apoptosis, cell motility, and migration. A drug repurposing screen and large-scale drug sensitivity screening data across 59 cancer cell lines and patient-derived cells were obtained from 125 glioblastoma samples. (3) Results: High-content analysis of patient-derived cells provided robust and accurate drug responses to c-Met-targeted agents. Only the cells of one glioblastoma patient (PDC6) showed elevated c-Met level and high susceptibility to the c-Met inhibitors. Multi-parameter image analysis also reflected a decreased c-Met expression and reduced cell growth and motility by a c-Met-targeting antibody. In addition, a drug repurposing screen identified Abemaciclib as a distinct CDK4/6 inhibitor with a potent c-Met-inhibitory function. Consistent with this, we present large-scale drug sensitivity screening data showing that the Abemaciclib response correlates with the response to c-Met inhibitors. (4) Conclusions: Our study provides a new insight into high-content screening platforms supporting drug sensitivity prediction and novel therapeutics screening.

Clonal evolution drives cancer progression and therapeutic resistance1-2. Recent longitudinal analyses revealed divergent clonal dynamics in adult diffuse gliomas3–11. However, the early genomic and epigenomic factors that steer post-treatment molecular trajectories remain unknown. To track evolutionary predictors, we analyzed sequencing and clinical data of matched initial-recurrent tumor pairs from 511 adult diffuse glioma patients. Using machine learning we developed methods capable of predicting grade progression and hypermutation from tumor characteristics at diagnosis. Strikingly, MYC copy number gain in initial tumors emerged as a key factor predicting development of hypermutation under temozolomide (TMZ) treatment. The driving role of MYC in TMZ-associated hypermutagenesis has been experimentally validated in a model of TMZ-induced hypermutator using both patient-derived gliomaspheres and established glioma cell lines. Subsequent studies showed that c-Myc binding to open chromatin and transcriptionally active regions increases the vulnerability of genomic regions to TMZ-induced mutagenesis. Consequently, MYC target genes, including the key mismatch repair genes, develop loss-of-function mutations, thus triggering the hypermutation process. This study reveals MYC as an early predictor of cancer evolution and provides a machine learning platform for predicting cancer dynamics to improve patient management.

Background There have been no evidence-based guidelines on the optimal schedule for the radiological assessment of 1p/19q-codeleted glioma. This study aimed to recommend an appropriate radiological evaluation schedule for 1p/19q-codeleted glioma during the surveillance period through parametric modeling of the progression-free survival (PFS) curve. Methods A total of 234 patients with 1p/19q-codeleted glioma (137 grade II and 97 grade III) who completed regular treatment were retrospectively reviewed. The patients were stratified into each layered progression risk group by recursive partitioning analysis. A piecewise exponential model was used to standardize the PFS curves. The cutoff value of the progression rate among the remaining progression-free patients was set to 10% at each scan. Results Progression risk stratification resulted in 3 groups. The optimal magnetic resonance imaging (MRI) interval for patients without a residual tumor was every 91.2 weeks until 720 weeks after the end of regular treatment following the latent period for 15 weeks. For patients with a residual tumor after the completion of adjuvant radiotherapy followed by chemotherapy, the optimal MRI interval was every 37.5 weeks until week 90 and every 132.8 weeks until week 361, while it was every 33.6 weeks until week 210 and every 14.4 weeks until week 495 for patients with a residual tumor after surgery only or surgery followed by radiotherapy only. Conclusions The optimal radiological follow-up schedule for each progression risk stratification of 1p/19q-codeleted glioma can be established from the parametric modeling of PFS.

The highly lethal brain cancer glioblastoma undergoes dynamic changes in molecular profile and cellular phenotype throughout tumor core establishment and in primary-to-recurrent tumor progression. These dynamic changes allow glioblastoma tumors to escape from multimodal therapies, resulting in patient lethality. Here, we identified the emergence of dependence on NEK2-mediated EZH2 signaling, specifically in therapy-resistant tumor core-located glioblastoma cells. In patient-derived glioblastoma core models, NEK2 was required for in vivo tumor initiation, propagation, and radio-resistance. Mechanistically, in glioblastoma core cells, NEK2 binds with EZH2 to prevent its proteasome-mediated degradation in a kinase-dependent manner. Clinically, NEK2 expression is elevated in recurrent tumors after therapeutic failure as opposed to their matched primary untreated cases, and its high expression is indicative of worse prognosis. For therapeutic development, we designed a novel NEK2 kinase inhibitor CMP3a, which effectively attenuated growth of murine glioblastoma models and exhibited a synergistic effect with radiation therapy. Collectively, the emerging NEK2-EZH2 signaling axis is critical in glioblastoma, particularly within the tumor core, and the small molecule inhibitor CMP3a for NEK2 is a potential novel therapeutic agent for glioblastoma.

Even after total resection of glioblastoma core lesions by surgery and aggressive post-surgical treatments, life-threatening tumors inevitably recur. A characteristic obstacle in effective treatment is high intratumoral heterogeneity, both longitudinally and spatially. Recurrence occurs predominantly at the brain parenchyma-tumor core interface, a region termed tumor edge. Given the difficulty of accessing it surgically, the composition of the tumor edge, harboring both cancerous and non-cancerous cells, remains largely unknown. Here, to identify phenotypic diversity among heterogeneous glioblastoma core and edge lesions, we uncovered the existence of three phenotypically-distinct clonal subpopulations within individual tumors from glioblastoma patients. Clones from the tumor core shared the same phenotype, exclusively generating tumor-core cells. In contrast, two distinct clonal subtypes were identified at the tumor edge: one generated only edge-lesion cells and the other expanded more broadly to establish both edge- and core-lesions. Using multiple xenograft experimental models in mouse brains, tumor edge development was found to require that both somatic and tumor cells express the NADase CD38, combinedly elevating glioblastoma malignancy. In vitro data suggested that intracellular NADase activity at the edge was provoked through intercellular communication between edge clones and normal astrocytes. Systemic treatment of tumor-bearing mice with 78c, a small-molecule CD38 inhibitor, attenuated the formation of glioblastoma edge lesions, suggesting its clinical potential to pharmacologically eliminate tumor-edge lesions. Collectively, these findings provide novel phenotypic and mechanistic insights into clonal heterogeneity within glioblastoma, particularly in the surgically unresectable, currently understudied tumor edge.

BACKGROUND To evaluate the impact of adjuvant postoperative radiotherapy (PORT) in adult WHO grade II–III intracranial ependymoma (IEPN). METHODS A total of 172 pathologically confirmed adult grade II–III IEPN patients from 12 institutions were eligible. Of them, 106 (61.6%) and 66 (38.4%) patients were grade II and III, respectively. For grade II and III IEPNs, 51 (48.1%) and 59 (89.4%) patients received PORT, respectively. The median dose to the primary tumor bed was 54.0 Gy and 59.4 Gy for grade II and III patients, respectively. The prognostic impact of sex, age, performance, WHO grade, location, size, surgical extent, and PORT on local control (LC), progression-free survival (PFS), and overall survival (OS) were evaluated by univariate and multivariate analysis. RESULTS The median follow-up period for survivors was 88.1 months. The 5-/10-year LC, PFS, and OS rates were 64.8%/54.0%, 56.4%/44.8%, and 76.6%/71.0%, respectively. On multivariate analysis, adjuvant PORT significantly improved LC (P=0.002), PFS (P=0.002), and OS (P=0.043). Older age (P< 0.001), WHO grade III (P< 0.001), larger tumor size (P=0.004), and lesser surgical extent (P< 0.001) were also negative factors for OS. Adjuvant PORT also improved LC (P=0.010), PFS (P=0.007), and OS (P=0.069) on multivariate analysis for grade II IEPNs. CONCLUSION This multicenter retrospective study supports the role of adjuvant PORT in terms of disease control and survival in adult grade II–III IEPNs. Prospective randomized trials focused on individualized treatment based on molecular subtypes is warranted.

BACKGROUNDS We aimed to evaluate the potential of radiomics as an imaging biomarker for GBM patients and explore the molecular rationale behind radiomics by radio-genomics approach. METHODS A total of 144 primary GBM patients were included in this study as a training cohort. Using multi-parametric MR images, radiomics features were extracted from multi-habitats of the tumor. We applied Cox-LASSO algorithm to build a survival prediction model and validated this model using an independent validation cohort (56 patients from Vienna). With the selected radiomics features, GBM patients were consensus clustered to reveal inherent phenotypic subtypes. The subtypes were further explored in terms of genomic signatures. RESULTS GBM patients were successfully stratified by the radiomics risk score, a weighted sum of radiomics features, corroborating the potential of radiomics as a prognostic biomarker. Using consensus clustering, we identified three distinct subtypes which significantly differed in the prognosis (‘heterogenous enhancing’, ‘rim-enhancing necrotic’, and ‘cystic’ subtype). Multi-variate cox regression analysis confirmed that radiomics subtype as an independent prognostic factor. Transcriptomic traits enriched in individual subtypes were in accordance with imaging phenotypes summarized by radiomics. For example, rim-enhancing necrotic subtype was well described by radiomics profiling (T2 autocorrelation & flat shape) and highlighted by the inflammatory genomic signatures, which well correlated to its phenotypic peculiarity (necrosis). CONCLUSIONS The present study confirmed the feasibility of radiomics as an imaging biomarker for GBM patients with comprehensible biologic annotation. Imaging subtypes derived from radiomics successfully recapitulate the genomic underpinnings of GBM tumors and in turn reinforce their potential as a prognostic biomarker.

Background Intended subtotal resection (STR) followed by adjuvant gamma knife radiosurgery (GKRS) has emerged as an effective treatment option for facial nerve (FN) preservation in vestibular schwannomas (VSs). This study aimed to identify the optimal cut-off volume of residual VS to predict favorable outcomes in terms of both tumor control and FN preservation. Methods This retrospective study assessed the patients who underwent adjuvant GKRS for residual VS after microsurgery. A total of 68 patients who had been followed up for ≥ 24 months after GKRS were included. Tumor progression was defined as an increase in tumor volume (TV) of ≥ 20%. House-Brackmann grades I and II were considered to indicate good FN function. Results The median residual TV was 2.5 cm3 (range: 0.3–27.4). The median follow-up period after the first adjuvant GKRS was 64 months (range: 25.7–152.4). Eight (12%) patients showed tumor progression. In multivariate analyses, residual TV was associated with tumor progression (P = 0.003; hazard ratio [HR], 1.229; 95% confidence interval [CI], 1.075–1.405). A residual TV of 6.4 cm3 was identified as the cut-off volume for showing the greatest difference in progression-free survival (PFS). The 5-year PFS rates in the group with residual TVs of < 6.4 cm3 (54 patients) and that with residual TVs of ≥ 6.4 cm3 (14 patients) were 93.3% and 69.3%, respectively (P = 0.014). A good FN outcome was achieved in 57 (84%) patients. Residual TV was not associated with good FN function during the immediate postoperative period (P = 0.695; odds ratio [OR], 1.024; 95% CI, 0.908–1.156) or at the last follow-up (P = 0.755; OR, 0.980; 95% CI, 0.866–1.110). Conclusion In this study, residual TV was associated with tumor progression in VS after adjuvant GKRS following STR. As preservation of FN function is not correlated with the extent of resection, optimal volume reduction is imperative to achieve long-term tumor control. Our findings will help surgeons predict the prognosis of residual VS after FN-preserving surgery., Graphical Abstract

We aimed to evaluate the preclinical efficacy of GC1118, a novel anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb), against glioblastoma (GBM) tumors using patient-derived xenograft (PDX) models. A total of 15 distinct GBM PDX models were used to evaluate the therapeutic efficacy of GC1118. Genomic data derived from PDX models were analyzed to identify potential biomarkers associated with the anti-tumor efficacy of GC1118. A patient-derived cell-based high-throughput drug screening assay was performed to further validate the efficacy of GC1118. Compared to cetuximab, GC1118 exerted comparable growth inhibitory effects on the GBM tumors in the PDX models. We confirmed that GC1118 accumulated within the tumor by crossing the blood&ndash, brain barrier in in vivo specimens and observed the survival benefit in GC1118-treated intracranial models. Genomic analysis revealed high EGFR amplification as a potent biomarker for predicting the therapeutic efficacy of GC1118 in GBM tumors. In summary, GC1118 exerted a potent anti-tumor effect on GBM tumors in PDX models, and its therapeutic efficacy was especially pronounced in the tumors with high EGFR amplification. Our study supports the importance of patient stratification based on EGFR copy number variation in clinical trials for GBM. The superiority of GC1118 over other EGFR mAbs in GBM tumors should be assessed in future studies.

Stereotactic radiosurgery such as Gamma Knife radiosurgery (GKRS) has been shown to have a good treatment effect for orbital cavernous venous malformation (CVM). However, radiation-induced retinopathy or optic neuropathy is a vision-threatening complication of orbital irradiation. Predicting the post-treatment visual outcome is critical. Clinical and radiological outcomes were investigated in 30 patients who underwent GKRS for orbital CVM between July 2005 and February 2020. Measurement of peripapillary retinal nerve fiber layer (pRNFL) thickness using optical coherence tomography (OCT) was obtained in 14 patients. The median clinical and radiological follow-up periods were 46.6 months (range, 15.9–105.8) and 27.5 months (range, 15.4–105.8), respectively. Twenty-eight patients underwent multisession (4 fractions) GKRS. The median cumulative marginal dose was 20 Gy (range, 16–24). Two patients underwent single-session GKRS. Marginal doses were 15 Gy and 10.5 Gy in each patient. The volume of CVM decreased in 29 (97%) patients. Visual acuity was improved in 6 (20%) patients and was stable in 22 (73%) patients. Visual field defect and exophthalmos were improved in all patients. Serial investigation of OCT showed no statistically significant difference in pRNFL thickness after GKRS. Patients with normal average pRNFL thickness showed better visual recovery than patients with thin average pRNFL thickness. GKRS is an effective and safe treatment option for orbital CVM. The pRNFL thickness before GKRS can be a prognostic indicator for visual recovery in orbital CVM after GKRS.

The prognostic and therapeutic relevance of molecular subtypes for the most aggressive isocitrate dehydrogenase 1/2 (IDH) wild-type glioblastoma (GBM) is currently limited due to high molecular heterogeneity of the tumors that impedes patient stratification. Here, we describe a distinct binary classification of IDH wild-type GBM tumors derived from a quantitative proteomic analysis of 39 IDH wild-type GBMs as well as IDH mutant and low-grade glioma controls. Specifically, GBM proteomic cluster 1 (GPC1) tumors exhibit Warburg-like features, neural stem-cell markers, immune checkpoint ligands, and a poor prognostic biomarker, FKBP prolyl isomerase 9 (FKBP9). Meanwhile, GPC2 tumors show elevated oxidative phosphorylation-related proteins, differentiated oligodendrocyte and astrocyte markers, and a favorable prognostic biomarker, phosphoglycerate dehydrogenase (PHGDH). Integrating these proteomic features with the pharmacological profiles of matched patient-derived cells (PDCs) reveals that the mTORC1/2 dual inhibitor AZD2014 is cytotoxic to the poor prognostic PDCs. Our analyses will guide GBM prognosis and precision treatment strategies., The heterogeneity of IDH1/2 wild-type glioblastoma limits its prognosis and therapy. Here, the authors show a binary stratification, based on quantitative proteomic analysis of samples from patients with glioblastoma, with different prognosis and therapeutic vulnerabilities.

Glioblastoma (GBM) is the most malignant brain tumor with profound genomic alterations. Tumor suppressor genes regulate multiple signaling networks that restrict cellular proliferation and present barriers to malignant transformation. While bona fide tumor suppressors such as PTEN and TP53 often undergo inactivation due to mutations, there are several genes for which genomic deletion is the primary route for tumor progression. To functionally identify putative tumor suppressors in GBM, we employed in vivo RNAi screening using patient-derived xenograft models. Here, we identified PIP4K2A, whose functional role and clinical relevance remain unexplored in GBM. We discovered that PIP4K2A negatively regulates phosphoinositide 3-kinase (PI3K) signaling via p85/p110 component degradation in PTEN-deficient GBMs and specifically targets p85 for proteasome-mediated degradation. Overexpression of PIP4K2A suppressed cellular and clonogenic growth in vitro and impeded tumor growth in vivo. Our results unravel a novel tumor-suppressive role of PIP4K2A for the first time and support the feasibility of combining oncogenomics with in vivo RNAi screen.

Most glioblastomas frequently recur at sites of radiotherapy, but it is unclear if changes in the tumor microenvironment due to radiotherapy influence glioblastoma recurrence. Here, we demonstrate that radiation-induced senescent glioblastoma cells exhibit a senescence-associated secretory phenotype that functions through NFκB signaling to influence changes in the tumor microenvironment, such as recruitment of Ly6G+ inflammatory cells and vessel formation. In particular, Ly6G+ cells promote conversion of glioblastoma cells to glioblastoma stem cells (GSCs) through the NOS2-NO-ID4 regulatory axis. Specific inhibition of NFκB signaling in irradiated glioma cells using the IκBα super repressor prevents changes in the tumor microenvironment and dedifferentiation of glioblastoma cells. Treatment with Ly6G-neutralizing antibodies also reduces the number of GSCs and prolongs survival in tumor-bearing mice after radiotherapy. Clinically, a positive correlation exists between Ly6G+ cells and the NOS2-NO-ID4 regulatory axis in patients diagnosed with recurrent glioblastoma. Together, our results illustrate important roles for Ly6G+ inflammatory cells recruited by radiation-induced SASP in cancer cell dedifferentiation and tumor recurrence.

To find genetic markers associated with response to radiotherapy (RT) in glioblastoma (GB) patients.From Jan 2009 to Dec 2016, 161 patients with newly diagnosed IDH-wild type GB were treated with surgery and adjuvant concurrent chemoradiotherapy with the Stupp's regimen, and then genomic research proceeded with their surgical specimens. Among the 161 patients, 49 with clinically measurable disease on postoperative MRI were analyzed. The response evaluation to RT was based on Response Assessment in Neuro-Oncology (RANO) criteria. For genomic analyses to compare between patients with progression and non-progression, Fisher test for DNA mutations and copy number alterations and the Gene Set Enrichment Analysis (GSEA) were performed.RT responses were non-progressive and progressive disease (PD) in 22 (44.9%) and 27 patients (55.1%), respectively. After three months, seven of PD exhibited pseudoprogression. For true response adjusting pseudoprogression from PD, 1-year progression-free survival for true Non-Responders (tNR-group) and true Responders (tR-group) were 0% and 45.4% (p 0.001), and overall survival were 52.5% and 81.1% (p = 0.046), respectively. In genomic analyses, the tNR-group had more CDKN2A deletions (94.4% vs. 55.6%, p = 0.013), EGFR mutations (33.3% vs. 3.7%, p = 0.012) and less TP53 mutations (22.2% vs. 40.7%, p = 0.333) than the tR-group. In GSEA, immune-related gene sets were enriched in the tNR-group, and in contrast, some gene sets related with cell cycle were enriched in tR-groups.The RANO criteria were feasible for the short-term response evaluation from RT despite of pseudoprogression. Genomic differences such as CDKN2A deletion, EGFR mutation, and immune- or inflammation-related related gene sets enrichment were found to be potentially predictive markers of RT.

The name of author Do Hoon Lim was incorrect in the initial online publication. The original article has been corrected.

BackgroundTumor cell-intrinsic mechanisms and complex interactions with the tumor microenvironment contribute to therapeutic failure via tumor evolution. It may be possible to overcome treatment resistance by developing a personalized approach against relapsing cancers based on a comprehensive analysis of cell type-specific transcriptomic changes over the clinical course of the disease using single-cell RNA sequencing (scRNA-seq).MethodsHere, we used scRNA-seq to depict the tumor landscape of a single case of chemo-resistant metastatic, muscle-invasive urothelial bladder cancer (MIUBC) addicted to an activating Harvey rat sarcoma viral oncogene homolog (HRAS) mutation. In order to analyze tumor evolution and microenvironmental changes upon treatment, we also applied scRNA-seq to the corresponding patient-derived xenograft (PDX) before and after treatment with tipifarnib, a HRAS-targeting agent under clinical evaluation.ResultsIn the parallel analysis of the human MIUBC and the PDX, diverse stromal and immune cell populations recapitulated the cellular composition in the human and mouse tumor microenvironment. Treatment with tipifarnib showed dramatic anticancer effects but was unable to achieve a complete response. Importantly, the comparative scRNA-seq analysis between pre- and post-tipifarnib-treated PDX revealed the nature of tipifarnib-refractory tumor cells and the tumor-supporting microenvironment. Based on the upregulation of programmed death-ligand 1 (PD-L1) in surviving tumor cells, and the accumulation of multiple immune-suppressive subsets from post-tipifarnib-treated PDX, a PD-L1 inhibitor, atezolizumab, was clinically applied; this resulted in a favorable response from the patient with acquired resistance to tipifarnib.ConclusionWe presented a single case report demonstrating the power of scRNA-seq for visualizing the tumor microenvironment and identifying molecular and cellular therapeutic targets in a treatment-refractory cancer patient.

Hypermutagenesis refers to marked increase in the number of mutations due to continuous mutagenic process. Hypermutated tumors, have being found in several tumor types, are associated with inherited or acquired alterations in the DNA repair pathways. Hypermutation has been observed in a subset of adult glioma patients as a direct result of temozolomide(TMZ)‐induced mutagenesis. In our study, we have identified a rare subset of treatment‐naïve adult gliomas with de novo hypermutator phenotype and explored the evolution of spontaneous and treatment‐induced hypermutagenesis. We conducted Whole‐Exome Sequencing (WES), Whole‐Transcriptome Sequencing (WTS), and Single‐Cell Sequencing (SCS) of TMZ‐naïve and post‐TMZ‐treated hypermutated tumors to identify distinct clinical or genomic manifestations that contribute to the development of hypermutation in untreated adult gliomas. TMZ‐naïve hypermutated tumors were marked by absence of IDH1 somatic mutation and MGMT promoter (pMGMT) methylation, two genomic traits that were significantly associated with the TMZ‐induced hypermutagenic event in glioblastoma, and harbored inherited alterations in the mismatch repair (MMR) machinery. The immediate family members of the TMZ‐naive hypermutated glioma patients were also previous diagnosed with cancer development history, suggesting that germline dysfunction of the MMR pathway could potentially pose hereditary risk to genetic predisposition of carcinogenesis in gliomas. Lastly, both TMZ‐naïve and post‐TMZ‐treated hypermutated tumors exhibited a significant accumulation of neoantigen loads, suggesting immunotherapeutic alternatives. Our results present new and unique understanding of hypermutagenic process in adult gliomas and an important step towards clinical implication of immunotherapy in glioma treatment., What's new? Hypermutation has been observed in a subset of adult glioma patients as a direct result of temozolomide (TMZ)‐induced mutagenesis, leading to therapeutic resistance. Here, the authors identified a rare subset of pre‐treatment adult glioma patients with de novo hypermutator phenotype. TMZ‐naïve hypermutated tumors lacked somatic mutation of IDH1 and MGMT promoter methylation, and harbored both germline and somatic dysregulation of mismatch repair machinery encoding genes. Patients with TMZ‐naïve hypermutagenesis demonstrated high incidence of cancer‐development history in their immediate family members. Both TMZ‐naïve and post‐TMZ treated hypermutated tumors exhibited a significant accumulatin of neoantigen loads, pointing towards potential implementation of immunotherapy.

A diverse series of compounds (18a–x) were synthesized from (S)-1-(chloromethyl)-8-methoxy-2,3-dihydro-1H-benzo[e]indol-5-ol (seco-MCBI) and benzoselenophene or heteroaromatic acids. These new compounds were evaluated for their cytotoxicity against the human gastric NCI-N87 and human ovarian SK-OV3 cancer cell lines. The incorporation of a methoxy substituent at the C-7 position of the seco-CBI unit enhances the cytotoxicity through its additional van der Waals interaction and gave a much higher potency than the corresponding seco-CBI-based analogues. Similarly, the seco-MCBI-benzoselenophene conjugates (18h–x) exhibited substitution effects on biological activity, and the N-butyramido and N-methylthiopropanamido analogues are highly potent, possessing >77- and >24-fold better activity than seco-MCBI-TMI for the SK-OV3 and NCI-N87 cell lines, respectively.

OBJECTIVEThe authors conducted this retrospective study to investigate the clinical outcomes of intracranial solitary fibrous tumor (SFT) and hemangiopericytoma (HPC), defined according to the 2016 WHO classification of central nervous system (CNS) tumors.METHODSHistopathologically proven intracranial SFT and HPC cases treated in the period from June 1996 to September 2014 were retrospectively reviewed and analyzed. Two neuropathologists reviewed pathological slides and regraded the specimens according to the 2016 WHO classification. Factors associated with progression-free survival (PFS) and overall survival (OS) were statistically evaluated with uni- and multivariate analyses.RESULTSThe records of 47 patients—10 with SFT, 33 with HPC, and 4 with anaplastic HPC—were reviewed. A malignant transition from conventional SFT to WHO grade III SFT/HPC was observed in 2 cases, and 13 HPC cases were assigned grade III SFT/HPC. Mean and median follow-ups were 114.6 and 94.7 months, respectively (range 7.1–366.7 months). Gross-total resection (GTR) was significantly associated with longer PFS and OS (p = 0.012 for both), and adjuvant radiation therapy versus no such therapy led to significantly longer PFS (p = 0.018). Extracranial metastases to the liver, bone, lung, spine, and kidney occurred in 10 patients (21.3%). Grade III SFT/HPC was strongly correlated with the development of extracranial metastases (p = 0.031).CONCLUSIONSThe 2016 WHO classification of CNS tumors reflected the different types of pathological malignant progression and clinical outcomes better than prior classifications. Gross-total resection should be the primary treatment goal in patients with SFT/HPC, regardless of the pathological grade, and radiation can be administered as adjuvant therapy for patients with SFT/HPC that shows an aggressive phenotype or that is not treated with GTR.

In terms of response to fractionated radiotherapy, metastatic brain tumors of certain origins are considered radioresistant. To determine the influence of “radioresistant” histology on outcomes of brain metastases treated with radiosurgery. Between 2001 and 2017, 121 patients with brain metastases from renal cell carcinoma (RCC) and 2151 from non-small cell lung cancer (NSCLC) were reviewed. Eighty-seven pairs were derived using propensity score matching. Local progression-free survival (PFS), progression patterns, distant PFS, and overall survival were investigated. The median follow-up period was 13.7 months (range, 1.6–78.4 months). A total of 536 lesions were treated using gamma knife radiosurgery (GKS), with a median dose of 20 Gy (range, 12–28 Gy). The actuarial local PFS rates in the RCC group were 91% and 89% at 6 and 12 months, respectively, and did not differ from the NSCLC group (97% and 83% at 6 and 12 months, respectively). Continuous progression, without response to GKS, was noted in seven of the eight progressed RCCs. However, six of the seven progressed NSCLCs showed transient shrinkage before progression. The median distant PFS was 9.3 months (95% CI, 6.3–12.2) in the RCC group and 8.0 months (95% CI, 5.5–10.4) in the NSCLC group. The median overall survival was 16.1 months (95% CI, 11.3–20.8) and 14.9 months (95% CI, 11.9–17.8) in RCC and NSCLC groups, respectively. Histological differences had no effect on local control in the single high-dose range used for radiosurgery. However, changes in tumor volume during progression varied across tumor histology.

To determine the feasibility of using high dimensional computer-extracted features, known as radiomics features, in differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma on multi-parametric MR imaging including diffusion-weighted imaging. Retrospective evaluation of data was approved by the local ethics committee and informed consent was waived. A total of 143 patients (two independent cohorts for discovery [n = 86; glioblastoma = 49, PCNSL = 37] and validation [n = 57; glioblastoma = 29, PCNSL = 28]) with newly diagnosed glioblastoma and PCNSL were subjected to radiomics analysis using the multi-parametric MRI (contrast-enhanced T1-weighted imaging, T2-weighted imaging, and diffusion-weighted imaging). Radiomics analyses were performed for two types of regions of interest (ROI) covering contrast-enhancing tumor and whole (enhancing or non-enhancing) tumor plus peritumoral edema. A total of 127 radiomics features were calculated. Feature selection was performed to identify the most discriminating features for every MR image in the discovery cohort. The identified features were used to calculate radiomics scores, which were later used in logistic regression to distinguish between PCNSL and glioblastoma. The classification model was further tested on the independent validation cohort. Fifteen features were selected as significant features in the discovery cohort. Using the identified features and calculated radiomics scores, the logistic regression-based classifier yielded an area under the curve (AUC) of 0.979, sensitivity of 0.938, and specificity of 0.944 in the discovery cohort to distinguish between glioblastoma and PCNSL. A similarly high rate of performance was observed in the validation cohort (AUC = 0.956). Radiomics features derived from multi-parametric MRI can be used to differentiate PCNSL from glioblastoma effectively.

Background Despite extensive efforts on the genomic characterization of gliomas, very few studies have reported the genetic alterations of cerebellar glioblastoma (C-GBM), a rare and lethal disease. Here, we provide a systematic study of C-GBM to better understand its specific genomic features. Methods We collected a cohort of C-GBM patients and compared patient demographics and tumor pathologies with supratentorial glioblastoma (S-GBM). To uncover the molecular characteristics, we performed DNA and mRNA sequencing and DNA methylation arrays on 19, 6, and 4 C-GBM cases, respectively. Moreover, chemical drug screening was conducted to identify potential therapeutic options for C-GBMs. Results Despite differing anatomical origins of C-GBM and S-GBM, neither histological, cytological, nor patient demographics appeared significantly different between the 2 types. However, we observed striking differences in mutational patterns, including frequent alterations of ATRX, PDGFRA, NF1, and RAS and absence of EGFR alterations in C-GBM. These results show a distinct evolutionary path in C-GBM, suggesting specific therapeutic targeted options. Targeted-drug screening revealed that C-GBMs were more responsive to mitogen-activated protein kinase kinase (MEK) inhibitor and resistant to epidermal growth factor receptor inhibitors than S-GBMs. Also, differential expression analysis indicated that C-GBMs may have originated from oligodendrocyte progenitor cells, suggesting that different types of cells can undergo malignant transformation according to their location in brain. Master regulator analysis with differentially expressed genes between C-GBM and proneural S-GBM revealed NR4A1 as a potential therapeutic target. Conclusions Our results imply that unique gliomagenesis mechanisms occur in adult cerebellum and new treatment strategies are needed to provide greater therapeutic benefits for C-GBM patients. Key points 1. Distinct genomic profiles of 19 adult cerebellar GBMs were characterized. 2. MEK inhibitor was highly sensitive to cerebellar GBM compared with supratentorial GBM. 3. Master regulator analysis revealed NR4A1 as a potential therapeutic target in cerebellar GBM.

Purpose Glioblastoma (GBM) is classified as one of the most aggressive and lethal brain tumor. Great strides have been made in understanding the genomic and molecular underpinnings of GBM, which translated into development of new therapeutic approaches to combat such deadly disease. However, there are only few therapeutic agents that can effectively inhibit GBM invasion in a clinical framework. In an effort to address such challenges, we have generated anti-SEMA3A monoclonal antibody as a potential therapeutic antibody against GBM progression. Materials and methods We employed public glioma datasets, Repository of Molecular Brain Neoplasia Data and The Cancer Genome Atlas, to analyze SEMA3AmRNA expression in human GBM specimens. We also evaluated for protein expression level of SEMA3A via tissue microarray (TMA) analysis. Cell migration and proliferation kinetics were assessed in various GBM patient-derived cells (PDCs) and U87-MG cell-line for SEMA3A antibody efficacy. GBM patient-derived xenograft (PDX) models were generated to evaluate tumor inhibitory effect of anti-SEMA3A antibody in vivo. Results By combining bioinformatics and TMA analysis, we discovered that SEMA3A is highly expressed in human GBM specimens compared to non-neoplastic tissues. We developed three different anti-SEMA3A antibodies, in fully human IgG form, through screening phage-displayed synthetic antibody library using a classical panning method. Neutralization of SEMA3A significantly reduced migration and proliferation capabilities of PDCs and U87-MG cell line in vitro. In PDX models, treatment with anti-SEMA3A antibody exhibited notable tumor inhibitory effect through down-regulation of cellular proliferative kinetics and tumor-associated macrophages recruitment. Conclusion In present study, we demonstrated tumor inhibitory effect of SEMA3A antibody in GBM progression and present its potential relevance as a therapeutic agent in a clinical framework.

Background Cancer is a complex disease with profound genomic alterations and extensive heterogeneity. Recent studies on large-scale genomics have shed light on the impact of core oncogenic pathways, which are frequently dysregulated in a wide spectrum of cancer types. Aberrant activation of the hepatocyte growth factor (HGF) signaling axis has been associated with promoting various oncogenic programs during tumor initiation, progression, and treatment resistance. As a result, HGF-targeted therapy has emerged as an attractive therapeutic approach. However, recent clinical trials involving HGF-targeted therapies have demonstrated rather disappointing results. Thus, an alternative, in-depth assessment of new patient stratification is necessary to shift the current clinical course. Methods To address such challenges, we have evaluated the therapeutic efficacy of YYB-101, an HGF-neutralizing antibody, in a series of primary glioblastoma stem cells (GSCs) both in vitro and in vivo. Furthermore, we performed genome and transcriptome analysis to determine genetic and molecular traits that exhibit therapeutic susceptibility to HGF-mediated therapy. Results We have identified several differentially expressed genes, including MET, KDR, and SOX3, which are associated with tumor invasiveness, malignancy, and unfavorable prognosis in glioblastoma patients. We also demonstrated the HGF-MET signaling axis as a key molecular determinant in GSC invasion, and we discovered that a significant association in HGF expression existed between mesenchymal phenotype and immune cell recruitment. Conclusions Upregulation of MET and mesenchymal cellular state are essential in generating HGF-mediated therapeutic responses. Our results provide an important framework for evaluating HGF-targeted therapy in future clinical settings.

A micropillar/microwell chip platform was applied to develop a 3D cell-based high-content screening (HCS) platform. Previously, 3D cell culture in the micropillar/microwell chip platform was only limited to cell viability measurements in a high-throughput manner. However, an HCS system could provide biological and phenotypic information which was very useful to understand complex biological functions and mechanisms of drug actions. To stain 3D cultured cells immobilized with alginate spots, we developed and optimized antibody staining procedures for 3D cultured cells. As a proof of concept, the phospho-EGFR (p-EGFR, a highly expressed receptor protein in cancer), F-actin (a protein of the actin cytoskeleton), and nuclei of 3D cultured cells were stained and analyzed after being treated with 72 different drugs. The p-EGFR inhibition of the drugs was successfully identified in the 3D cultured cells by comparing p-EGFR expression with that of F-actin and the nucleus. The p-EGFR expression levels were also measured by Western blot to verify the chip data.

Objective Despite advances in endoscopic techniques, retrochiasmatic craniopharyngiomas (CPs) are difficult to remove completely, because the low-lying optic chiasm often provides an obstacle to an endoscopic endonasal approach. This study aimed to identify the endoscopic surgical outcomes of the retrochiasmatic CP and resolve the issues related to low-lying optic chiasm. Methods We reviewed 154 consecutive patients with CP who underwent endonasal endoscopic resection from February 2009 to April 2017 at 2 independent institutions. The topographic relationship of the tumor with the third ventricle, stalk, and optic chiasm and clinical outcomes were investigated. Results Retrochiasmatic CPs were found in 142 of 154 patients (92.2%). The median follow-up time was 25 months. Gross total resection and near-total resection were achieved in 113 patients (79.6%) and 21 patients (13.8%), respectively. Postoperative cerebrospinal fluid leaks were found in 16 patients (11.3%). Low-lying and high-lying chiasms were found in 44 patients (31.0%) and 98 patients (69.0%), respectively. Low-lying chiasm did not affect clinical outcomes including the extent of resection. Patients with low-lying chiasm showed a marginal trend for postoperative visual deterioration. The ventricular growth pattern representing the origin of the tumor and previous surgery were significantly associated with the position of the optic chiasm (P = 0.007 and 0.001, respectively). Conclusions An endoscopic endonasal approach is an effective surgical approach for retrochiasmatic CP, even in tumors with low-lying chiasm. However, a thorough and careful dissection is necessary to prevent visual deterioration.

// Hye Ree Kim 1 , Chang Hoon Shin 1 , Hong Lee 1 , Kyung Hee Choi 1 , Do-Hyun Nam 1, 2 , Takbum Ohn 3 , Hyeon Ho Kim 1, 4 1 Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, Republic of Korea 2 Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea 3 Department of Cellular and Molecular Medicine, College of Medicine, Chosun University, Gwangju, Republic of Korea 4 Research Institute for Future Medicine, Samsung Medical Center, Seoul, Republic of Korea Correspondence to: Hyeon Ho Kim, email: hyeonhkim@skku.edu Takbum Ohn, email: tohn@chosun.ac.kr Keywords: SRSF3, FADS1, miR-1908-5p, NF-κB, NKIRAS2 Received: August 24, 2016 Accepted: November 22, 2016 Published: December 26, 2016 ABSTRACT Serine/arginine (SR)-rich proteins that contain RS domains and SR repeats have diverse cellular functions including transcription, polyadenylation, translation, and RNA export. The splicing factor SRSF3, also termed SRp20, is the smallest member of the SR protein family and is a known proto-oncogene. Although it is implicated in the malignant phenotypes of various cancer cells, the molecular mechanism underlying SRSF3-mediated cancer progression is still obscure. We investigated here the oncogenic functions of SRSF3 in osteosarcoma U2OS cells. Knockdown of SRSF3 inhibited proliferation, clonogenicity, and metastatic potential including migration and invasion. It also decreased the level of miR-1908 independent of its host gene FADS1 . Although FADS1 was not associated with SRSF3-mediated malignant properties, overexpression of miR-1908-5p increased cell proliferation, migration, and invasion, suggesting that miR-1908-5p is responsible for the oncogenic functions of SRSF3. Knockdown of SRSF3 decreased the expression of miR-1908-5p by inhibiting transactivation of NF-κB. We observed that miR-1908-5p downregulated NF-κB inhibitor interacting Ras-like 2 ( NKIRAS2 ), a negative regulator of the NF-κB pathway by directly binding to the 3’UTR of NKIRAS2 mRNA. Consistent with overexpression of miR-1908-5p, knockdown of NKIRAS2 diminished the expression level of IκB-β and provoked translocation of NF-κB into the nucleus where it transcriptionally activates its target genes including miR-1908-5p expression, thus elevating the proliferation and metastatic potential. Taken together, our results demonstrate that SRSF3 confers the malignant characteristics on cancer cells via the SRSF3/miR-1908-5p/NKIRAS2 axis.

// Doo-Sik Kong 1,* , Do-Hyun Nam 1,* , Shin-Hyuk Kang 2 , Jae Won Lee 3 , Jong-Hee Chang 4 , Jeong-Hoon Kim 5 , Young-Jin Lim 6 , Young-Cho Koh 7 , Yong-Gu Chung 2 , Jae-Min Kim 8 and Choong-Hyun Kim 8 1 Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea 2 Department of Neurosurgery, College of Medicine, Korea University, Seoul, Korea 3 Department of Statistics, Korea University, Seoul, Korea 4 Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea 5 Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea 6 Department of Neurosurgery, Kyunghee University Hospital, Seoul, Korea 7 Department of Neurosurgery, Konkuk University Medical Center, Seoul, Korea 8 Department of Neurosurgery, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea * These authors have contributed equally to this work Correspondence to: Choong Hyun Kim, email: // Keywords : immunotherapy, autologous cytokine-induced killer cell, glioblastoma Received : August 05, 2016 Accepted : September 23, 2016 Published : September 27, 2016 Abstract Purpose: Adoptive cell immunotherapy involves an ex vivo expansion of autologous cytokine-induced killer (CIK) cells before their reinfusion into the host. We evaluated the efficacy and safety of CIK cell immunotherapy with radiotherapy-temozolomide (TMZ) for the treatment of newly diagnosed glioblastomas. Experimental design: In this multi-center, open-label, phase 3 study, we randomly assigned patients with newly diagnosed glioblastoma to receive CIK cell immunotherapy combined with standard TMZ chemoradiotherapy (CIK immunotherapy group) or standard TMZ chemoradiotherapy alone (control group). The efficacy endpoints were analyzed in the intention-to-treat set and in the per protocol set. Results: Between December 2008 and October 2012, a total of 180 patients were randomly assigned to the CIK immunotherapy ( n = 91) or control group ( n = 89 ). In the intention-to-treat analysis set, median PFS was 8.1 months (95% confidence interval (CI), 5.8 to 8.5 months) in the CIK immunotherapy group, as compared to 5.4 months (95% CI, 3.3 to 7.9 months) in the control group (one-sided log-rank, p = 0.0401). Overall survival did not differ significantly between two groups. Grade 3 or higher adverse events, health-related quality of life and performance status between two groups did not show a significant difference. Conclusions: The addition of CIK cells immunotherapy to standard chemoradiotherapy with TMZ improved PFS. However, the CIK immunotherapy group did not show evidence of a beneficial effect on overall survival.

// Nakho Chang 1, 2, 3, * , Hye Won Lee 3, 4, * , Joung Eun Lim 5 , Da Eun Jeong 1 , Hye Jin Song 6 , Sudong Kim 3, 7 , Do-Hyun Nam 1, 2, 3 , Hyun Hwan Sung 5 , Byong Chang Jeong 5 , Seong Il Seo 5 , Seong Soo Jeon 5 , Hyun Moo Lee 5 , Han-Yong Choi 5 , Hwang Gyun Jeon 5 1 Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul 06351, Korea 2 Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea 3 Institute for Refractory Cancer Research, Samsung Medical Center, Seoul 06351, Korea 4 Institute for Future Medicine, Samsung Medical Center, Seoul 06351, Korea 5 Department of Urology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea 6 Department of Anatomy and Cell Biology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea 7 Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Seoul 06351, Korea * These authors contributed equally to this work Correspondence to: Hwang Gyun Jeon, email: hwanggyun.jeon@samsung.com Keywords: muscle invasive bladder cancer, PTEN, EGFR, drug screening, patient-derived xenograft Received: May 20, 2016 Accepted: June 29, 2016 Published: July 12, 2016 ABSTRACT Muscle-invasive bladder cancer (MIBC) consists of a heterogeneous group of tumors with a high rate of metastasis and mortality. To facilitate the in-depth investigation and validation of tailored strategies for MIBC treatment, we have developed an integrated approach using advanced high-throughput drug screening and a clinically relevant patient-derived preclinical platform. We isolated patient-derived tumor cells (PDCs) from a rare MIBC case (BD-138T) that harbors concomitant epidermal growth factor receptor (EGFR) amplification and phosphatase and tensin homolog (PTEN) deletion. High-throughput in vitro drug screening demonstrated that dasatinib, a SRC inhibitor, and PKI-587, a dual PI3K/mTOR inhibitor, exhibited targeted anti-proliferative and pro-apoptotic effects against BD-138T PDCs. Using established patient-derived xenograft models that successfully retain the genomic and molecular characteristics of the parental tumor, we confirmed that these anti-tumor responses occurred through the inhibition of SRC and PI3K/AKT/mTOR signaling pathways. Taken together, these experimental results demonstrate that dasatinib and PKI-587 might serve as promising anticancer drug candidates for treating MIBC with combined EGFR gene amplification and PTEN deletion.

During tumor development, stromal cells are co-opted to the tumor milieu and provide favorable conditions for the tumor. Hypoxia stimulates cancer cells to acquire a more malignant phenotype via activation of hypoxia-inducible factor 1 (HIF-1). Given that cancer cells and astrocytes in glioblastomas coexist in a hypoxic microenvironment, we examined whether astrocytes affect the adaptation of glioblastoma cells to hypoxia. Immunoblotting, reporter assays, quantitative RT-PCR, and chromatin immunoprecipitation were performed to evaluate HIF-1 signaling in glioblastoma cells. Astrocyte-derived chemokine C-C motif ligand 20 (CCL20) was identified using cytokine arrays, and its role in glioblastoma development was evaluated in orthotopic xenografts. Astrocytes augmented HIF-1α expression in glioblastoma cells under hypoxia. The expression of HIF-1 downstream genes, cancer colony formation, and Matrigel invasion of glioblastoma cells were stimulated by conditioned medium from astrocytes pre-exposed to hypoxia. CCL20 was secreted in a hypoxia-dependent manner from astrocytes and busted the hypoxic induction of HIF-1α in glioblastoma cells. Mechanistically, the CCL20/CCR6 signaling pathway upregulates HIF-1α by stimulating nuclear factor kappa B-driven transactivation of the HIF1A gene. Compared with the control tumors, CCR6-deficient glioblastoma xenografts grew more slowly, with poor vascularization, and expressed lower levels of HIF-1α and its downstream proteins. Furthermore, CCR6 expression was correlated with HIF-1α expression in GEO and TCGA datasets from human glioblastoma tissues. These results suggest that glioblastoma cells adapt well to hypoxic stress by virtue of CCL20 derived from neighboring astrocytes.

PURPOSE: Phyllodes tumors (PTs) of the breast are rare, accounting for less than 1% of all breast tumors. Among PTs, malignant PTs (MPTs) have malignant characteristics and distant metastases occur in about 20% to 30% of MPTs. However, there is no effective treatment for MPTs with distant metastasis, resulting in an abject prognosis. We performed targeted deep sequencing on PTs to identify the associations between genetic alterations and clinical prognosis. METHODS: We performed targeted deep sequencing to evaluate the genetic characteristics of PTs and analyzed the relationships between clinical and genetic characteristics. RESULTS: A total of 17 PTs were collected between 2001 and 2012. Histologic review was performed by pathologists. The samples included three benign PTs, one borderline PT, and 13 MPTs. The most frequently detected genetic alteration occurred in the TERT promoter region (70.6%), followed by MED12 (64.7%). EGFR amplification and TP53 alteration were detected in four MPTs without genetic alterations in MED12 and TERT promoter regions. Genetic alterations of RARA and ZNF703 were repeatedly found in PTs with local recurrence, and genetic alterations of SETD2 , BRCA2, and TSC1 were detected in PTs with distant metastasis. Especially, MPT harboring PTEN and RB1 copy number deletion showed rapid disease progression. CONCLUSIONS: In this study, we provide genetic characterization and potential therapeutic target for this rare, potentially lethal disease. Further large-scale comprehensive genetic study and functional validation are warranted.

This study was performed to determine the clinical significance of the Ki-67 labeling index (LI) for local control (LC) in patients with World Health Organization (WHO) grade II meningioma. We also tried to discern the effect of postoperative radiotherapy (PORT) on LC depending upon the Ki-67 LI value. The medical records and values of Ki-67 LIs were retrospectively reviewed for 50 patients who underwent surgical resection of intracranial WHO grade II meningiomas at Samsung Medical Center from May 2001 to December 2012. Forty-three patients (86%) were treated with immediate PORT. The median total radiation dose was 60 Gy (range, 54 to 60 Gy). The median follow-up was 47.4 months. The mean Ki-67 LI was 13% (range, 1% to 47%). Twelve patients (24.0%) showed local failure, and 8 patients (16.0%) experienced local failure even after PORT. The mean Ki-67 LI was 15% in patients with local failure (n=12) and 12% in patients without local failure (n=38). The 3-year actuarial LC was 80.5%. The 3-year overall survival was 89.5%. Ki-67 LI>13% and PORT were significant prognostic factors for LC (P=0.015 and 0.009, respectively). In patients with Ki-67 LI>13% (n=17), PORT (n=14) improved LC (P13%, PORT should be recommended to improve LC.

The RET fusion is considered as the potential novel target in solid tumors. However, RET fusion is not well yet identified in colorectal cancer (CRC), and the effect of RET kinase inhibitor is also not evaluated in CRC with RET fusion. We established patient-derived tumor cells (PDCs) with RET fusion from recurrent brain metastatic lesion that newly appeared during the surveillance for stage III CRC patient. To investigate therapeutic options to CRC patient with a RET fusion, we performed cell viability assays using the PDCs. NCOA4-RET fusion was detected by FusionPlex using the resected brain metastatic tissue of CRC patient with solitary brain metastasis and then reconfirmed by fluorescence in situ hybridization (FISH) test. We also confirmed the RET fusions by a qPCR in matched PDCs. We tested whether the PDCs from RET fusion colon cancer were sensitive to carbozantinib, sorafenib, vandetanib, and PD0331992. Cell viability assays showed that carbozantinib, sorafenib, and PD0332991 did not suppress cell viability. Only, vandetanib revealed the significant inhibitory effect in MTT proliferation assay. Next, we analyzed regulation of targeted downstream pathways upon exposure to vandetanib by immunoblot assay. In colon cancer PDCs with NCOA4-RET fusion, vandetanib potently inhibited AKT and ERK phosphorylation. This study shows that vandetanib might be one of useful treatment strategies for CRC patient with NCOA4-RET fusion. Therefore, inhibition of the RET kinase is a promising targeted therapy for cancer patients whose tumors harbor a RET rearrangement.

PURPOSE Preoperative diagnosis of prolactinomas is critical because medication of dopamine agonists instead of surgical resection has been regarded as a primary treatment. However, serum prolactin level alone is suboptimal for differentiating the prolactin producing adenoma or hyperprolactinemia-causing NFPAs. The author investigated the use of ratio of PRL levels to the tumor size as the optimal cutoff value for prolactin-producing tumor, comparing with the NFPA. METHOD We performed a retrospective review of patients who underwent the transsphenoidal surgery (TSS) for pituitary lesions in the single institute between January 2015 to May 2020. A total of 223 patients with hyperprolactinemia at the initial diagnosis were analyzed in the study, including NFPA patients (n=175) and prolactinoma patients (n=48). Receiver operating curve (ROC) analyses were performed for serum prolactin levels (PRL) and serum prolactin levels/tumor maximal diameter (PRL/MD). RESULT Prolactinoma group showed higher median values in serum PRL (258.6 μg/L) and smaller maximal tumor diameter (16.6 mm), compared to those of NFPA group (serum PRL 44.4 μg/L, p-value = 0.002 and MD 23.9 mm, p-value < 0.001). A moderate correlation was found between serum prolactin level and maximal diameters in prolactinomas (r=0.43, p=0.002), whereas a weak relationship was confirmed in NFPAs (r=0.17, p=0.028). The cutoff was 8.93 μg/L*mm (area under the curve [AUC] = 0.94) for PRL/MD and 99.43 μg/L for PRL (AUC = 0.91). In prolactinomas, there was no statistical difference between the PRL/MD of macroadenomas (n=36, 21.7μg/L*mm) and microadenoma (n=12, 16.8μg/L*mm) (p=0.109). CONCLUSION The serum PRL levels and tumor size exhibited stronger linear correlation in prolactinomas than in NFPAs. The PRL/MD ratio showed better diagnostic value for differentiating two pathologies than the serum PRL levels alone. These findings suggest PRL/MD ratio may be an alternative method to preoperative diagnosis of prolactinomas differentiating from hyperprolactinemia-causing NFPAs.

The receptor tyrosine kinase c-Met plays critical roles in promoting tumor growth, invasion, metastasis, and angiogenesis in various types of cancer and is a promising therapeutic target. The development of a species cross-reactive therapeutic antibody could provide useful to comprehensive preclinical assessment in animal models. Towards this goal, we developed human/mouse cross-reactive c-Met antibodies using an antibody phage library. IRCR201, a c-Met antibody with species cross-reactivity, successfully inhibited the HGF/c-Met signaling pathway via degradation of c-Met and disruption of the binding with its partners, and demonstrated strong in vivo antitumor activity. In pharmacokinetic analysis, IRCR201 exhibited a nonlinear pharmacokinetic profile and showed rapid serum clearance at low dosage. Ex vivo fluorescence imaging and immunohistochemistry demonstrated strong tumor accumulation of IRCR201. Hepatotoxicity analysis revealed that IRCR201 does not significantly affect primary human and mouse hepatocytes. Serum chemistry analysis demonstrated that the alanine aminotransferase serum level was elevated in mice treated with 30 mg/kg IRCR201 than in PBS-treated mice, whereas the levels of aspartate aminotransferase and blood urea nitrogen did not significantly differ. Thus, IRCR201 is a potent therapeutic antibody that can disrupt the HGF/c-Met signaling axis and its species cross-reactivity would enable to evaluate precise biological activity in animal models.