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Introduction: To explore and evaluate the performance of MRI-based brain tumor super-resolution generative adversarial network (MRBT-SR-GAN) for improving the MRI image resolution in brain tumors., Methods: A total of 237 patients from December 2018 and April 2020 with T2-fluid attenuated inversion recovery (FLAIR) MR images (one image per patient) were included in the present research to form the super-resolution MR dataset. The MRBT-SR-GAN was modified from the enhanced super-resolution generative adversarial networks (ESRGAN) architecture, which could effectively recover high-resolution MRI images while retaining the quality of the images. The T2-FLAIR images from the brain tumor segmentation (BRATS) dataset were used to evaluate the performance of MRBT-SR-GAN contributed to the BRATS task., Results: The super-resolution T2-FLAIR images yielded a 0.062 dice ratio improvement from 0.724 to 0.786 compared with the original low-resolution T2-FLAIR images, indicating the robustness of MRBT-SR-GAN in providing more substantial supervision for intensity consistency and texture recovery of the MRI images. The MRBT-SR-GAN was also modified and generalized to perform slice interpolation and other tasks., Conclusions: MRBT-SR-GAN exhibited great potential in the early detection and accurate evaluation of the recurrence and prognosis of brain tumors, which could be employed in brain tumor surgery planning and navigation. In addition, this technique renders precise radiotherapy possible. The design paradigm of the MRBT-SR-GAN neural network may be applied for medical image super-resolution in other diseases with different modalities as well., (© 2022 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

Background: Abnormal proliferation and migration of cells are hallmarks of cancer initiation and malignancy. Asparagine endopeptidase (AEP) has specific substrate cleavage ability and plays a pro-cancer role in a variety of cancers. However, the underlying mechanism of AEP in cancer proliferation and migration still remains unclear., Methods: Co-immunoprecipitation and following mass spectrometry were used to identify the substrate of AEP. Western blotting was applied to measure the expression of proteins. Single cell/nuclear-sequences were done to detect the heterogeneous expression of Tmod3 in tumor tissues. CCK-8 assay, flow cytometry assays, colony formation assay, Transwell assay and scratch wound-healing assay were performed as cellular functional experiments. Mouse intracranial xenograft tumors were studied in in vivo experiments., Results: Here we showed that AEP cleaved a ubiquitous cytoskeleton regulatory protein, tropomodulin-3 (Tmod3) at asparagine 157 (N157) and produced two functional truncations (tTmod3-N and tTmod3-C). Truncated Tmod3 was detected in diverse tumors and was found to be associated with poor prognosis of high-grade glioma. Functional studies showed that tTmod3-N and tTmod3-C enhanced cancer cell migration and proliferation, respectively. Animal models further revealed the tumor-promoting effects of AEP truncated Tmod3 in vivo. Mechanistically, tTmod3-N was enriched in the cell cortex and competitively inhibited the pointed-end capping effect of wild-type Tmod3 on filamentous actin (F-actin), leading to actin remodeling. tTmod3-C translocated to the nucleus, where it interacted with Staphylococcal Nuclease And Tudor Domain Containing 1 (SND1), facilitating the transcription of Ras Homolog Family Member A/Cyclin Dependent Kinases (RhoA/CDKs)., Conclusion: The newly identified AEP-Tmod3 protease signaling axis is a novel "dual-regulation" mechanism of tumor cell proliferation and migration. Our work provides new clues to the underlying mechanisms of cancer proliferation and invasive progression and evidence for targeting AEP or Tmod3 for therapy., (© 2022. The Author(s).)

Pseudogenes, which are long noncoding RNAs that originate from protein-coding genes, have been suggested to play important roles in disease. Although studies have revealed high expression of legumain (LGMN) in many types of tumors, the regulation of LGMN remains largely unknown. Here, we found that a novel LGMN pseudogene (LGMNP1) was upregulated in glioblastoma (GBM) tissues and high LGMNP1 expression in GBM cells enhanced proliferation and invasion. Biochemical analysis showed that cytoplasmic LGMNP1 functionally targeted miR-495-3p in a manner involving an RNA-induced silencing complex. Dual-luciferase reporter assays demonstrated that LGMN was a target of miR-495-3p, and LGMN was upregulated and positively correlated with LGMNP1 in GBM. Moreover, miR-495-3p was downregulated and negatively correlated with LGMNP1 in GBM tissues. Notably, the tumor-promoting effects of LGMNP1 upregulation could be alleviated by miR-495-3p mimics. Furthermore, GBM cells overexpressing LGMNP1 exhibited more aggressive tumor progression and elevated LGMN expression in vivo. Thus, our data illustrate that LGMNP1 exerts its oncogenic activity, at least in part, as a competitive endogenous RNA (ceRNA) that elevates LGMN expression by sponging miR-495-3p. CeRNA-mediated miRNA sequestration might be a novel therapeutic strategy in GBM., (Copyright © 2020. Published by Elsevier B.V.)

Background: Circular RNAs (circRNAs), a newly discovered type of endogenous noncoding RNA, have been proposed to mediate the progression of diverse types of tumors. Systematic studies of circRNAs have just begun, and the physiological roles of circRNAs remain largely unknown. Here, we focused on elucidating the potential role and molecular mechanism of circular forkhead box O3 (circFOXO3) in glioblastoma (GBM) progression., Methods: First, we analyzed circFOXO3 alterations in GBM and noncancerous tissues through real-time quantitative reverse transcription PCR (qRT-PCR). Next, we used loss- and gain-of-function approaches to evaluate the effect of circFOXO3 on GBM cell proliferation and invasion. Mechanistically, fluorescent in situ hybridization, RNA pull-down, dual luciferase reporter, and RNA immunoprecipitation assays were performed to confirm the interaction between circFOXO3 and miR-138-5p/miR-432-5p in GBM. An animal model was used to verify the in vitro experimental findings., Results: CircFOXO3 expression was significantly higher in GBM tissues than in noncancerous tissues. GBM cell proliferation and invasion were reduced by circFOXO3 knockdown and enhanced by circFOXO3 overexpression. Further biochemical analysis showed that circFOXO3 exerted its pro-tumorigenic activity by acting as a competing endogenous RNA (ceRNA) to increase expression of nuclear factor of activated T cells 5 (NFAT5) via sponging both miR-138-5p and miR-432-5p. Notably, tumor inhibition by circFOXO3 downregulation could be reversed by miR-138-5p/miR-432-5p inhibitors in GBM cells. Moreover, GBM cells with lower circFOXO3 expression developed less aggressive tumors in vivo., Conclusions: Our data demonstrate that circFOXO3 can exert regulatory functions in GBM and that ceRNA-mediated microRNA sequestration might be a potential strategy for GBM therapy., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Long non-coding RNAs (lncRNAs) play vital roles in the pathobiology of glioblastoma multiforme (GBM). Though radiotherapy remains the most effective component of multiple therapies for patients with GBM, lncRNAs conferring GBM radioresistance are less unknown. Here, the present study identified that the antisense transcript of hypoxia-inducible factor-1α (AHIF) was upregulated in GBM cells after radiotherapy. The deregulation of AHIF affected GBM cell clonogenic formation, DNA repair and apoptosis. Notably, knockdown of AHIF inhibited tumorigenesis after radiotherapy in vivo. Further biochemical analysis identified that AHIF regulated proteins associated with apoptosis after radiotherapy. Thus, the present data illustrate that suppression of AHIF increases radiosensitivity in GBM cells, which may be a potential diagnostic and therapeutic target for GBM patients., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Glioblastoma multiforme (GBM) has the highest mortality rate among patients with brain tumors, and radiotherapy forms an important part of its treatment. Thus, there is an urgent requirement to elucidate the mechanisms conferring GBM progression and radioresistance. In the present study, it was identified that antisense transcript of hypoxia‑inducible factor‑1α (AHIF) was significantly upregulated in GBM cancerous tissues, as well as in radioresistant GBM cells. The expression of AHIF was also upregulated in response to radiation. Knockdown of AHIF in GBM cells decreased viability and invasive capacities, and increased the proportion of apoptotic cells. By contrast, overexpression of AHIF in GBM cells increased viability and invasive capacities, and decreased the proportion of apoptotic cells. Furthermore, exosomes derived from AHIF‑knockdown GBM cells inhibited viability, invasion and radioresistance, whereas exosomes derived from AHIF‑overexpressing GBM cells promoted viability, invasion and radioresistance. Further biochemical analysis identified that AHIF regulates factors associated with migration and angiogenesis in exosomes. To the best of our knowledge, the present study is the first to establish that AHIF promotes glioblastoma progression and radioresistance via exosomes, which suggests that AHIF is a potential therapeutic target for GBM.

Neurocutaneous melanosis (NCM) is a rare congenital syndrome characterized by the presence of multiple congenital melanocytic nevi and the proliferation of melanocytes in the central nervous system. The authors present a 9-year-old Chinese boy whose clinical manifestations are intermittent headache for 2 months and persistent abdominal pain for 10 days. 3D-reconstruction computed tomography angiography image, digital subtraction angiography, and magnetic resonance imaging plus angiography (MRI+MRA) examinations results suggested that cavernoma at left frontal lobe potentially associated with hemorrhage. In addition, miliary abnormal signals were widely scattered on MRA image so that other malignant metastatic diseases cannot be ruled out. GI physical examination had not any abnormal findings, antispasmodic drugs were ineffective but antiepilepsy drugs were effective to abdominal pain. In surgery, no cavernoma was noticed but an accumulation of densely melanocytic mass located at the lesion on radiology images. The lesions spread along with perivascular of sylvian veins and leptomeningeal. Pathology investigation demonstrated brain metastatic malignant melanoma associated with hemosiderosis. The lesion of brain parenchyma was totally removed but the spread lesions could not be treated with surgery. Adjuvant radiotherapy was performed but failed to control the malignant development, still the patient died in 3 months postinitial operation. The authors conclude that abdominal pain was a manifestation of epilepsy related to the frontal lobe lesion. Neurocutaneous melanosis is a rare disease, brain metastases result in abdominal pain is rare even more, and it is worth the attention of clinicians.

MicroRNAs (miRNAs) are small noncoding RNAs that negatively regulate protein biosynthesis and participate in the pathogenesis of various tumours. Previous studies have shown that miR-210 is highly expressed in different types of human cancers, including glioblastoma multiforme (GBM). However, the role that miR-210 plays in GBM remains unclear. Here, we detected the expression and examined the function of miRNA-210 in GBM cells. Furthermore, we investigated the possible molecular mechanisms by which miRNA-210 mediates cell proliferation and apoptosis. Fifteen GBM and five normal brain tissues, in addition to the U87MG and U251 GBM cell lines, were analysed in this study. We found that miR-210 was upregulated in GBM tissues and cell lines when compared to normal brain tissue. Cell counting and flow cytometric assay results demonstrated that upregulation of miR-210 induced cell proliferation and decreased cell apoptosis, respectively. In addition, downregulation of miR-210 inhibited cell proliferation and induced apoptosis. We also detected a miR-210 target, regulator of differentiation 1 (ROD1), which is involved in GBM progression. Knockdown of ROD1 reversed the growth arrest and apoptosis that were originally induced by miR-210 inhibition. We propose that miR-210 regulates cell proliferation and apoptosis in GBM cells by targeting ROD1. Our findings may provide a new potential therapeutic target for the treatment of GBM.

MicroRNA-155 is highly expressed in many malignant tumors with poor prognosis, which regulates cell apoptosis, proliferation, invasion, metastasis, tumor angiogenesis, and metabolism. This study aims at investigating the clinical significance of miR-155 expression in human gliomas. Real-time quantitative PCR was used to detect the expression levels of miR-155 in 131 glioma and 16 normal brain tissues. The association of miR-155 expression with clinicopathological factors and prognosis of glioma patients were analyzed. The expression levels of miR-155 were significantly higher in glioma tissues than that in normal brain tissues (P < 0.001), which was associated with high pathological grade (P < 0.001) and low Karnofsky Performance Status score (P = 0.022). As a result of Kaplan-Meier survival and Cox regression analyses, overall survival (OS) rates and progression-free survival were significantly poorer in high-expression group relative to low-expression group (both P < 0.001). Furthermore, miR-155 expression was significantly associated with poor OS (P < 0.001) and PFS (P = 0.001) in glioma patients who had high pathological grades (III-IV) as calculated by subgroup analyses. These findings reveal that miR-155 expression might be an independent prognostic factor and a therapeutic target for human glioma.