METTL3-mediated HOTAIRM1 promotes vasculogenic mimicry icontributionsn glioma via regulating IGFBP2 expression.

BACKGROUND: HOTAIRM1 is revealed to facilitate the malignant progression of glioma. Vasculogenic mimicry (VM) is critically involved in glioma progression. Nevertheless, the molecular mechanism of HOTAIRM1 in regulating glioma VM formation remains elusive. Thus, we attempted to clarify the role and mechanism of HOTAIRM1 in VM formation in glioma. METHODS: qRT-PCR and western blot assays were used to evaluate the gene and protein expression levels of HOTAIRM1 in glioma patient tissue samples and cell lines. The role of HOTAIRM1 in glioma cell progression and VM formation was explored using a series of function gain-and-loss experiments. RNA-binding protein immunoprecipitation (RIP), RNA pull-down, and mechanism experiments were conducted to assess the interaction between HOTAIRM1/METTL3/IGFBP2 axis. Furthermore, rescue assays were conducted to explore the regulatory function of HOTAIRM1/METTL3/IGFBP2 in glioma cell cellular processes and VM formation. RESULTS: We found that HOTAIRM1 presented up-regulation in glioma tissues and cells and overexpression of HOTAIRM1 facilitated glioma cell proliferation, migration, invasion, and VM formation. Furthermore, overexpression of HOTAIRM1 promoted glioma tumor growth and VM formation capacity in tumor xenograft mouse model. Moreover, HOTAIRM1 was demonstrated to interact with IGFBP2 and positively regulated IGFBP2 expression. IGFBP2 was found to promote glioma cell malignancy and VM formation. Mechanistically, METTL3 was highly expressed in glioma tissues and cells and was bound with HOTAIRM1 which stabilized HOTAIRM1 expression. Rescue assays demonstrated that METTL3 silencing counteracted the impact of HOTAIRM1 on glioma cell malignancy and VM formation capacity. CONCLUSION: HOTAIRM1, post-transcriptionally stabilized by METTL3, promotes VM formation in glioma via up-regulating IGFBP2 expression, which provides a new direction for glioma therapy.

N6-methyladenosine-modified HOTAIRM1 promotes vasculogenic mimicry formation in glioma.

Vasculogenic mimicry (VM) has been reported to accelerate angiogenesis in malignant tumors, yet the mechanism underlying VM has not been fully elucidated. N6-methyladenosine (m6A) mainly modulates mRNA fate and affects multiple tumorigenesis. Here, we aimed to investigate m6A-modified HOXA transcript antisense RNA myeloid-specific 1 (HOTAIRM1) in the regulation of glioma-associated VM formation. Gene expression was analyzed by quantitative RT-PCR. Cell viability, metastases, and VM formation capacity were determined by CCK-8, migration and invasion, as well as tube formation assays, respectively. The function and mechanisms of m6A-modified HOTAIRM1 were defined through liquid chromatography-tandem mass spectrometry m6A quantification, methylated RNA immunoprecipitation sequencing, RNA stability assays, and RNA pull-down experiments. A glioma xenograft mouse model was further established for VM evaluation in vivo. The results showed that HOTAIRM1, methyltransferase-like 3 (METTL3), and insulin-like growth factor binding protein 2 (IGFBP2) were upregulated in glioma tissues and cell lines. HOTAIRM1 functions as an oncogene in glioma progression; however, knockdown of HOTAIRM1 significantly reduced cell viability, migration, invasion, and VM formation. Notably, METTL3-dependent m6A modification enhanced HOTAIRM1 mRNA stability, whereas knockdown of METTL3 deficiency significantly suppressed VM in glioma. Moreover, HOTAIRM1 was found to bind IGFBP2, and HOTAIRM1 deficiency blocked glioma progression and VM formation in vivo. Our results indicated that METTL3-dependent m6A-modified HOTAIRM1 promoted VM formation in glioma.

FOXM1-mediated NUF2 expression confers temozolomide resistance to human glioma cells by regulating autophagy via the PI3K/AKT/mTOR signaling pathway.

Glioma is the most common malignant tumor in the central nervous system and has a high mortality rate. Temozolomide (TMZ) is a widely used chemotherapeutic drug for glioma. NDC80 kinetochore complex (NUF2) is suggested to play a regulatory role in different cancers, but its specific function and mechanism in glioblastoma TMZ resistance remain unknown. NUF2, assessed by reverse transcription quantitative polymerase chain reaction (RT-qPCR), was highly expressed in glioma cell lines. TMZ was used to treat cells to establish a TMZ-resistant cell line. The potential functions of NUF2 in glioma were assessed using cell counting kit-8 (CCK-8) assays, colony formation assays, 5-Ethynyl-2'-deoxyuridine (EdU) assays, flow cytometry, Western blotting, and a tumor xenograft model. The results showed that NUF2 knockdown attenuated malignant phenotypes of TMZ-resistant cells and prevented tumor growth. Mechanistically, as luciferase reporter assays and chromatin immunoprecipitation (ChIP) as showed, Fox transcription factor M1 (FOXM1) had binding sites on the NUF2 promoter. Rescue assays demonstrated that FOXM1 upregulation counteracted the inhibitory effects of NUF2 depletion on the malignancies of TMZ-resistant cells. This study demonstrates that FOXM1-activated NUF2 promotes TMZ to human glioma cells by regulating proliferation, apoptosis, and autophagy.

Reconstruction for diverse fronto-orbital defects with computer-assisted designed and computer-assisted manufactured PEEK implants in one-stage operation: Case reports.

RATIONAL: Reconstruction of complex craniofacial defects in fronto-orbital region has been reported to be extremely few. In this study, we report 2 cases with fronto-orbital defects of different etiologies in one-stage surgical reconstruction with polyetheretherketone (PEEK) prosthesis using computer-assisted design and computer-assisted manufactured (CAD-CAM) techniques. PATIENT CONCERNS: One patient was a 49-year-old man, who admitted with a depressed and comminuted fracture in the left fronto-orbital region as a result of a motor vehicle collision. The other patient was a 45-year-old woman who was hospitalized with an unexpected diagnosis of a fronto-orbital bone tumor during a head CT examination in a minor traumatic brain injury. None of them had a significant past medical history. DIAGNOSES: The first patient's head computed tomography (CT) showed multiple depressed comminuted fractures in the right fronto-orbital region with localized frontal lobe contusion, and the diagnosis was clear when combined with the mechanism of traumatic head injuries. The second patient's head CT and magnetic resonance image suggested a right lateral orbital neoplastic lesion that distorted peripheral bone, the postoperative pathological examination demonstrated an osteoma with fibromatous hyperplasia, and thus the women's diagnosis was confirmed. INTERVENTIONS: A three-dimensional image of both patients' skull bone were collected from a high-resolution CT. A virtual surgical planning for lesion excision and defect remodeling based on CAD-CAM techniques was undertaken, and than the reconstruction surgery was performed in a single procedure using PEEK prosthesis. Antibacterial treatment was prescribed routinely. OUTCOMES: Postoperatively, both patients achieved excellent aesthetic restoration as well as functional recovery of the orbital cavity without neurological or infectious complications during an average 22 months follow-up. LESSONS: The CAD-CAM PEEK implants could be a preferred option for reconstruction of patients with various complex fronto-orbital defects.

Long noncoding RNA LINC00515 promotes cell proliferation and inhibits apoptosis by sponging miR-16 and activating PRMT5 expression in human glioma.

Introduction: In recent years, an increasing amount of literature has demonstrated the functional role of long non-coding RNA (lncRNA) in human diseases. LINC00515 is a newly defined lncRNA and is reported to act as an oncogene in multiple myeloma. However, the function of LINC00515 in glioma is still uncertain. Materials and methods: We examined the expression levels of LINC00515 in human glioma tissues and cell lines using real-time PCR analysis. In addition, we confirmed the distribution of LINC00515 in glioma cells and suppressed LINC00515 expression with siRNAs. CCK-8, colony formation assay and apoptosis analysis were used to study the function of LINC00515 in glioma progression. Then, we used bioinformatics prediction and subsequent experiments to reveal the underlying molecular mechanism. Results: We found that LINC00515 was up-regulated in glioma tissues and cell lines. LINC00515 was mainly located in the cytoplasm in glioma cells. Knockdown of LINC00515 led to decreased proliferation and increased apoptosis of glioma cells. Mechanistically, our data indicated that there was a LINC00515/miR-16/PRMT5 regulatory axis in glioma. LINC00515 could activate PRMT5 expression and promote glioma progression by acting as a sponge of miR-16. Conclusion: LINC00515 expression is elevated in human glioma and promotes growth and inhibits apoptosis of glioma cells. The regulatory cascade LINC00515/miR-16/PRMT5 plays a critical role in glioma progression.

MicroRNA-128 inhibits proliferation and invasion of glioma cells by targeting COX-2.

MicroRNAs (miRNA), a class of small noncoding RNAs, regulates message RNA (mRNA) by targeting the 3'-untranslated region (3'-UTR) resulting in suppression of gene expression. In this study, we identified the expression and function of miR-128, which was found to be downregulated in glioma tissues and glioma cells by real time PCR. Overexpression of miR-128 mimics into LN229 and U251 cells could inhibit proliferation and invasion of glioma cells. However, the inhibitory effects of miR-128 mimics on the invasion and proliferation of glioma cells were reversed by overexpression of cyclooxygenase-2 (COX-2). Our data showed that COX-2 was a candidate target of miR-128. Luciferase activity of 3'-UTR of COX-2 was reduced in the presence of miR-128. Additionally, miR-128 obviously decreased COX-2 mRNA stability determined by real time PCR. Contrarily, we found that miR-128 inhibitor significantly increased the COX-2 mRNA expression, and elevated the protein expression of MMP9 and ki67, and promoted the proliferation of glioma cells. Furthermore, luciferase activity of the 3'-UTR was upregulated by miR-128 inhibitor. All of these results supported that miR-128 was a direct regulator of COX-2. Further studies proved that COX-2 was elevated in glioma tissues and its expression was negatively correlated with the levels of miR-128. These findings may establish miR-128 as a new potential target for the treatment of patients with gliomas.

Use of Pneumoperitoneal Puncture for Peritoneal Catheter Placement in Lumboperitoneal Shunt Surgery: Technical Note.

BACKGROUND: In hydrocephalus shunt surgery, a peritoneal catheter is traditionally inserted with laparotomy incision. The abdominal incision length will not be shorter than 3 cm in most cases. A longer incision has to be made in obese patients. The lateral position in lumboperitoneal shunt (LPS) surgery also increases the difficulty of laparotomy. This report introduces a simple technique of pneumoperitoneal puncture for peritoneal catheter placement in LPS surgery. METHODS: Twenty-eight communicating hydrocephalus cases underwent pneumoperitoneal puncture in an LPS operation. Abdominal incision length, time for peritoneal catheter placement, and postoperative complications were recorded. RESULTS: The length of the abdominal incision was 1 cm, and the average time for peritoneal catheter placement was 3.5 minutes. No patient suffered from infection and obstruction. Two cases of subdural hematoma because of cerebrospinal fluid overdrainage occurred. CONCLUSIONS: The pneumoperitoneal puncture technique has proven, in our experience, to be a minimally invasive, simple, and reliable method in a peritoneal catheter placement procedure. This technique, which needs to be assessed further by larger case series, may be considered a new method of choice for peritoneal catheter placement in LPS surgery.