Complex interactions between the components of the PI3K/AKT/mTOR pathway, and with components of MAPK, JAK/STAT and Notch-1 pathways, indicate their involvement in meningioma development

The FGF6 amplification mutation plays an important role in the progression and treatment of malignant meningioma

Meningioma is a benign tumor with slow growth and long course. However, patients with recurrent malignant meningioma still face a lack of effective treatment. Here, we report a rare case of primary mediastinal malignant meningioma with lung and bone metastases, who benefited from the treatment of apatinib (≥33 months) and anlotinib (until the publication date). Retrospective molecular analysis revealed the frequent amplification of FGF6 in primary and metastatic lesions. Then we constructed the FGF6 over-expressed IOMM-LEE and CH157MN malignant meningioma cell lines, and in vitro and vivo experiments showed that overexpression of FGF6 can promote the proliferation, migration and invasion of malignant meningioma cells. Based on the Western analysis, we revealed that FGF6 can promote the phosphorylation of FGFR, AKT, and ERK1/2, which can be inhibited by anlotinib. Together, we were the first to verify that overexpression of FGF6 promotes the progression of malignant meningiomas by activating FGFR/AKT/ERK1/2 pathway and pointed out that anlotinib may effectively inhibit the disease progression of patients with FGF6 amplification.

Hsa_circ_0004872 alleviates meningioma progression by sponging miR-190a-3p/PTEN signaling

BACKGROUND

Meningioma, the most prevalent intracranial tumor, possesses a significant propensity for malignant transformation. Circular RNAs (circ-RNAs), a class of non-coding RNAs, have emerged as crucial players in tumorigenesis. This study explores the functional relevance of hsa_circ_0004872, a specific circ-RNA, in the context of meningioma.

METHODS

Molecular structure and stability of hsa_circ_0004872 were elucidated through PCR identification. Meningioma cell proliferation and apoptosis were assessed using the CCK-8 assay and flow cytometry, respectively. Gene and protein expression were analyzed via qRT-PCR and western blot. Molecular interactions were confirmed through dual-luciferase reporter gene and RIP assays.

RESULTS

Hsa_circ_0004872, derived from exons 2 to 4 of the host gene MAPK1, demonstrated enhanced stability compared to its host MAPK1. Clinical data described that hsa_circ_0004872 was reduced in meningioma tissues and cell lines, and negatively correlated to poor survival rate of meningioma patients. Overexpression of hsa_circ_0004872 exhibited inhibitory effects on cell proliferation and promotion of apoptosis in vitro. Subsequent investigations unveiled a direct interaction between hsa_circ_0004872 and miR-190a-3p, leading to the activation of the PI3K/AKT signaling pathway through targeting PTEN. Notably, miR-190a-3p silence accelerated the apoptosis and proliferation inhibition of meningioma cells by inactivating PTEN/PI3K/AKT signaling, while miR-190a-3p overexpression showed an opposite effect, which greatly reversed the anti-tumor effects of hsa_circ_0004872 overexpression.

CONCLUSION

In summary, our findings highlighted the intricate role of hsa_circ_0004872 in meningioma, shedding light on the regulatory mechanisms involving circ-RNAs in tumor progression. This positions hsa_circ_0004872 as a potential key regulatory factor in meningioma with implications for future therapeutic interventions.

External auditory canal ectopic atypical meningioma: A case report and brief literature review

Meningiomas are tumours typically derived from the meningothelial cells of the arachnoid mater. They most often arise in intracranial, intraspinal, or orbital locations. Ectopic meningiomas, described as primary meningiomas with no intracranial involvement, are definitely unconventional. In fact, most of the extracranial meningiomas described in the literature, particularly in the outer ear, are effectively spreads of disease with primary intracranial localization. We describe a case of a primary external auditory canal meningioma with demonstrated absence of intracranial involvement, and we provide a full radiological, histological, immunohistochemical and molecular characterization of the lesion.

Interplay between signal transducers and activators of transcription (STAT) proteins and cancer: involvement, therapeutic and prognostic perspective

Signal transducers and activators of transcription or STAT are proteins that consist of various transcription factors that are responsible for activating genes regarding cell proliferation, differentiation, and apoptosis. They commonly activate several cytokine, growth, or hormone factors via the JAK-STAT signaling pathway by tyrosine phosphorylation which are responsible for giving rise to numerous immune responses. Mutations within the Janus-Kinases (JAKs) or the STATs can set off the commencement of various malfunctions of the immune system of the body; carcinogenesis being an inevitable outcome. STATs are known to act as both oncogenes and tumor suppressor genes which makes it a hot topic of investigation. Various STATs related mechanisms are currently being investigated to analyze its potential of serving as a therapeutic base for numerous immune diseases and cancer; a deeper understanding of the molecular mechanisms involved in the signaling pathways can contribute to the same. This review will throw light upon each STAT member in causing cancer malignancies by affecting subsequent signaling pathways and its genetic and epigenetic associations as well as various inhibitors that could be used to target these pathways thereby devising new treatment options. The review will also focus upon the therapeutic advances made in cancers that most commonly affect people and discuss how STAT genes are identified as prognostic markers.

DNA methylation meningioma biomarkers: attributes and limitations

Meningioma, one of the most common primary central nervous system tumors, are classified into three grades by the World Health Organization (WHO) based on histopathology. The gold-standard treatment, surgical resection, is hampered by issues such as incomplete resection in some cases and a high recurrence rate. Alongside genetic alterations, DNA methylation, plays a crucial role in progression of meningiomas in the occurrence and development of meningiomas. The epigenetic landscape of meningioma is instrumental in refining tumor classification, identifying robust molecular markers, determining prognosis, guiding treatment selection, and innovating new therapeutic strategies. Existing classifications lack comprehensive accuracy, and effective therapies are limited. Methylated DNA markers, exhibiting differential characteristics across varying meningioma grades, serve as invaluable diagnostic tools. Particularly, combinatorial methylated markers offer insights into meningioma pathogenesis, tissue origin, subtype classification, and clinical outcomes. This review integrates current research to highlight some of the most promising DNA and promoter methylation markers employed in meningioma diagnostics. Despite their promise, the development and application of DNA methylation biomarkers for meningioma diagnosis and treatment are still in their infancy, with only a handful of DNA methylation inhibitors currently clinically employed for meningioma treatment. Future studies are essential to validate these markers and ascertain their clinical utility. Combinatorial methylated DNA markers for meningiomas have broad implications for understanding tumor development and progression, signaling a paradigm shift in therapeutic strategies for meningiomas.

A proteome-level view of brain tumors for a better understanding of novel diagnosis, prognosis, and therapy

INTRODUCTION

Brain tumors are complex and heterogeneous malignancies with significant challenges in diagnosis, prognosis, and therapy. Proteomics, the large-scale study of proteins and their functions, has emerged as a powerful tool to comprehensively investigate the molecular mechanisms underlying brain tumor regulation.

AREAS COVERED

This review explores brain tumors from a proteomic standpoint, highlighting recent progress and insights gained through proteomic methods. It delves into the proteomic techniques employed and underscores potential biomarkers for early detection, prognosis, and treatment planning. Recent PubMed Central proteomic studies (2017-present) are discussed, summarizing findings on altered protein expression, post-translational changes, and protein interactions. This sheds light on brain tumor signaling pathways and their significance in innovative therapeutic approaches.

EXPERT OPINION

Proteomics offers immense potential for revolutionizing brain tumor diagnosis and therapy. To unlock its full benefits, further translational research is crucial. Combining proteomics with other omics data enhances our grasp of brain tumors. Validating and translating proteomic biomarkers are vital for better patient results. Challenges include tumor complexity, lack of curated proteomic databases, and the need for collaboration between researchers and clinicians. Overcoming these challenges requires investment in technology, data sharing, and translational research.

The Epigenetic Landscape of Meningiomas

Epigenetic changes have been found to be increasingly important in tumor development and progression. These alterations can be present in tumors such as meningiomas in the absence of any gene mutations and alter gene expression without affecting the sequence of the DNA itself. Some examples of these alterations that have been studied in meningiomas include DNA methylation, microRNA interaction, histone packaging, and chromatin restructuring. In this chapter we will describe in detail each of these mechanisms of epigenetic modification in meningiomas and their prognostic significance.

Molecular determinants of outcomes in meningiomas

Meningiomas are the most common intracranial primary tumor in adults. Surgery is the predominant therapeutic modality for symptomatic meningiomas. Although the majority of meningiomas are benign, there exists a subset of meningiomas that are clinically aggressive. Recent advances in genetics and epigenetics have uncovered molecular alterations that drive tumor meningioma biology with prognostic and therapeutic implications. In this review, we will discuss the advances on molecular determinants of therapeutic response in meningiomas to date and discuss findings of targeted therapies in meningiomas.

NF2 Alteration/22q Loss Is Associated with Recurrence in WHO Grade 1 Sphenoid Wing Meningiomas

Sphenoid wing meningiomas account for 11−20% of all intracranial meningiomas and have a higher recurrence rate than those at other sites. Recent molecular biological analyses of meningiomas have proposed new subgroups; however, the correlation between genetic background and recurrence in sphenoid wing meningiomas has not yet been fully elucidated. In this study, we evaluated the clinical characteristics, pathological diagnosis, and molecular background of 47 patients with sphenoid wing meningiomas. Variants of NF2, AKT1, KLF4, SMO, POLR2A, PIK3CA, TRAF7, and TERT were determined using Sanger sequencing, and 22q loss was detected using multiplex ligation-dependent probe amplification. Alterations were localized at NF2 in 11 cases, had other genotypes in 17 cases, and were not detected in 12 cases. Interestingly, WHO grade 1 meningiomas with NF2 alteration/22q loss (p = 0.008) and a MIB-1 labeling index > 4 (p = 0.03) were associated with a significantly shorter recurrence-free survival, and multivariate analysis revealed that NF2 alteration/22q loss was associated with recurrence (hazard ratio, 13.1). The duration of recurrence was significantly shorter for meningiomas with NF2 alteration/22q loss (p = 0.0007) even if gross-total resection was achieved. Together, these findings suggest that NF2 alteration/22q loss is associated with recurrence in WHO grade 1 sphenoid wing meningiomas.

mTOR Signaling and Potential Therapeutic Targeting in Meningioma

Meningiomas are the most frequent primary tumors arising in the central nervous system. They typically follow a benign course, with an excellent prognosis for grade I lesions through surgical intervention. Although radiotherapy is a good option for recurrent, progressive, or inoperable tumors, alternative treatments are very limited. mTOR is a protein complex with increasing therapeutical potential as a target in cancer. The current understanding of the mTOR pathway heavily involves it in the development of meningioma. Its activation is strongly dependent on PI3K/Akt signaling and the merlin protein. Both factors are commonly defective in meningioma cells, which indicates their likely function in tumor growth. Furthermore, regarding molecular tumorigenesis, the kinase activity of the mTORC1 complex inhibits many components of the autophagosome, such as the ULK1 or Beclin complexes. mTOR contributes to redox homeostasis, a vital component of neoplasia. Recent clinical trials have investigated novel chemotherapeutic agents for mTOR inhibition, showing promising results in resistant or recurrent meningiomas.

Gansui-Banxia Decoction extraction inhibits MDSCs accumulation via AKT /STAT3/ERK signaling pathways to regulate antitumor immunity in C57bl/6 mice

BACKGROUND

Gansui-Banxia Decoction (GSBXD) is a classic formula of traditional Chinese medical (TCM) sage Zhang Zhongjing to treat stagnation of evil heat and obstruction of qi. At present GSBXD is wildly used to treat cancerous ascites, pleural effusion, peritoneal effusion, pericardial effusion, cranial cavity effusion and several types of cancers, such as hepatocellular carcinoma (HCC) and esophageal cancer. Myeloid-derived suppressor cells (MDSCs) are a kind of immature and heterogeneous cells which can suppress lymphocytes activation by forming a suppressive environment. MDSCs accumulation in peripheral blood and tumors are closely related to the cancer stage and low survival rate of clinical patients. The antitumor immune effect of GSBXD has not received widespread attention.

PURPOSE

To investigate the effects of GSBXD on MDSCs accumulation and the mediators including AKT/STAT3/ERK signaling pathways.

METHODS

The chemical components of GSBXD were analyzed by UHPLC-MS, and the putative pathways of GSBXD based on Network pharmacology were predicted. Mice were vaccinated with Hepatoma 22 (H22) to establish tumor growth model, which were then administrated with GSBXD ethanol extraction (0.49 mg/kg/day, 1.75 mg/kg/day), sorafenib (60 mg/kg) or saline for 14 days. The cell morphology was evaluated by hematoxylin and eosin (H&E) staining, and immunity cells were determined through flowcytometry analysis. The levels of cytokines production in blood were evaluated by using ELISA kits. STAT3, ERK and AKT/mTOR signaling transduction associated proteins were determined by Western blot.

RESULTS

GSBXD could inhibit tumor growth and splenomegaly in H22 tumor model mice. Importantly, GSBXD reduced MDSCs accumulation and differentiation, and inhibited proliferation of F4/80⁺ CD11b⁺ macrophages and apoptosis of T cells and B cells, and increased the percentage of CD 3^- NK1.1⁺ NK cells. To better understand the active component of GSBXD, the ethanol-extraction powdered GSBXD was prepared and analyzed by UHPLC-MS. Combined with these main chemical compounds, we predicted that the anti-tumor effect of GSBXD mainly mediated PI3K-AKT and RAS-MAPK signal pathways based on Network Pharmacology. Western blot analysis of tumor tissues and MDSCs cells demonstrated that phosphorylation of AKT, ERK and STAT3 were significantly reduced, specially the activation of ERK. The levels of IL-1β and IFN-γ were significantly decreased by ELISA analysis.

CONCLUSION

GSBXD exhibited antitumor immune activity by reducing the accumulation of MDSCs in vivo, which is possible via down-regulation of AKT/STAT3/ERK signaling pathway and suppression of IL-1β and IFN-γ.

Receptor-Tyrosine Kinase Inhibitor Ponatinib Inhibits Meningioma Growth In Vitro and In Vivo

To date, there is no standard-of-care systemic therapy for the treatment of aggressive meningiomas. Receptor tyrosine kinases (RTK) are frequently expressed in aggressive meningiomas and are associated with poor survival. Ponatinib is a FDA- and EMA-approved RTK inhibitor and its efficacy in meningioma has not been studied so far. Therefore, we investigated ponatinib as a potential drug candidate against meningioma. Cell viability and cell proliferation of ponatinib-treated meningioma cells were assessed using crystal violet assay, manual counting and BrdU assay. Treated meningioma cell lines were subjected to flow cytometry to evaluate the effects on cell cycle and apoptosis. Meningioma-bearing mice were treated with ponatinib to examine antitumor effects in vivo. qPCR was performed to assess the mRNA levels of tyrosine kinase receptors after ponatinib treatment. Full-length cDNA sequencing was carried out to assess differential gene expression. IC50 values of ponatinib were between 171.2 and 341.9 nM in three meningioma cell lines. Ponatinib induced G0/G1 cell cycle arrest and subsequently led to an accumulation of cells in the subG1-phase. A significant induction of apoptosis was observed in vitro. In vivo, ponatinib inhibited meningioma growth by 72.6%. Mechanistically, this was associated with downregulation of PDGFRA/B and FLT3 mRNA levels, and mitochondrial dysfunction. Taken together, ponatinib is a promising candidate for targeted therapy in the treatment of aggressive meningioma.

Impact of STAT Proteins in Tumor Progress and Therapy Resistance in Advanced and Metastasized Prostate Cancer

Signal transducers and activators of transcription (STATs) are a family of transcription factors involved in several biological processes such as immune response, cell survival, and cell growth. However, they have also been implicated in the development and progression of several cancers, including prostate cancer (PCa). Although the members of the STAT protein family are structurally similar, they convey different functions in PCa. STAT1, STAT3, and STAT5 are associated with therapy resistance. STAT1 and STAT3 are involved in docetaxel resistance, while STAT3 and STAT5 are involved in antiandrogen resistance. Expression of STAT3 and STAT5 is increased in PCa metastases, and together with STAT6, they play a crucial role in PCa metastasis. Further, expression of STAT3, STAT5, and STAT6 was elevated in advanced and high-grade PCa. STAT2 and STAT4 are currently less researched in PCa. Since STATs are widely involved in PCa, they serve as potential therapeutic targets. Several inhibitors interfering with STATs signaling have been tested unsuccessfully in PCa clinical trials. This review focuses on the respective roles of the STAT family members in PCa, especially in metastatic disease and provides an overview of STAT-inhibitors evaluated in clinical trials.

Curcumin Inhibits HGF-Induced EMT by Regulating c-MET-Dependent PI3K/Akt/mTOR Signaling Pathways in Meningioma

Meningiomas, which are the most common primary intracranial tumors, have highly aggressive cells in malignant cases. Due to its extensive antitumor effects, curcumin is widely used in experimental and clinical studies. However, the role of curcumin during the epithelial-mesenchymal transition (EMT) in meningioma has not been established. We found that curcumin blocks hepatocyte growth factor- (HGF-) induced proliferation, migration, invasion, and EMT of human malignant meningioma cells by regulating the PI3K/Akt/mTOR signaling pathway. In addition, treatment of human malignant meningioma cells with the tyrosine protein kinase (c-MET) inhibitor (SU11274) or the phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) suppressed HGF-induced migration and EMT. Furthermore, we found that curcumin inhibited tumor growth and HGF-induced EMT in mice subjected to subcutaneous xenotransplantation. These findings indicate that HGF regulates EMT in human malignant meningioma cells through c-MET/PI3K/Akt/mTOR modulation. In conclusion, curcumin inhibits HGF-induced EMT by targeting c-MET and subsequently blocking the PI3K/Akt/mTOR pathway.

The Spectrum, Tendency and Predictive Value of PIK3CA Mutation in Chinese Colorectal Cancer Patients

Background

PIK3CA is a high-frequency mutation gene in colorectal cancer, while its prognostic value remains unclear. This study evaluated the mutation tendency, spectrum, prognosis power and predictive power in cetuximab treatment of PIK3CA in Chinese CRC cohort.

Methods

The PIK3CA exon 9 and 20 status of 5763 CRC patients was detected with Sanger sequencing and a high-resolution melting test. Clinicopathological characteristics of 5733 patients were analyzed. Kaplan-Meier method and nomogram were used to evaluate the overall survival curve and disease recurrence, respectively.

Results

Fifty-eight types of mutations in 13.4% (771/5733) of the patients were detected. From 2014 to 2018, the mutation rate of PIK3CA increased from 11.0% to 13.5%. At stage IV, exon 20 mutated patients suffered shorter overall survival time than wild-type patients (multivariate COX regression analysis, HR = 2.72, 95% CIs = 1.47-5.09; p-value = 0.012). At stage III, PIK3CA mutated patients were more likely to relapse (multivariate Logistic regression analysis, exon 9: OR = 2.54, 95% CI = 1.34-4.73, p = 0.003; exon 20: OR = 3.89, 95% CI = 1.66-9.10, p = 0.002). The concordance index of the nomogram for predicting the recurrence risk of stage III patients was 0.685. After cetuximab treatment, the median PFS of PIK3CA exon 9 wild-type patients (n = 9) and mutant patients (n = 5) did not reach a significant difference (3.6 months vs. 2.3 months, Log-rank test, p-value = 0.513).

Conclusions

We found that PIK3CA mutation was an adverse predictive marker for the overall survival of stage IV patients and recurrence of stage III patients, respectively. Further more, we suggested that PIK3CA exon 9 mutations are not negative predictors of cetuximab treatment in KRAS, NRAS, and BRAF wild-type mCRC patients.

Combined inhibition of RNA polymerase I and mTORC1/2 synergize to combat oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the major cause of morbidity and mortality in head and neck cancer patients worldwide. This malignant disease is challenging to treat because of the lack of effective curative strategies and the high incidence of recurrence. This study aimed to investigate the efficacy of a single and dual approach targeting ribosome biogenesis and protein translation to treat OSCC associated with the copy number variation (CNV) of ribosomal DNA (rDNA). Here, we found that primary OSCC tumors frequently exhibited a partial loss of 45S rDNA copy number and demonstrated a high susceptibility to CX5461 (a selective inhibitor of RNA polymerase I) and the coadministration of CX5461 and INK128 (a potent inhibitor of mTORC1/2). Combined treatment displayed the promising synergistic effects that induced cell apoptosis and reactive oxygen species (ROS) generation, and inhibited cell growth and proliferation. Moreover, INK128 compromised NHEJ-DNA repair pathway to reinforce the antitumor activity of CX5461. In vivo, the cotreatment synergistically suppressed tumor growth, triggered apoptosis and strikingly extended the survival time of tumor-bearing mice. Additionally, treatment with the individual compounds and coadministration appeared to reduce the incidence of enlarged inguinal lymph nodes. Our study supports that the combination of CX5461 and INK128 is a novel and efficacious therapeutic strategy that can combat this cancer and that 45S rDNA may serve as a useful indicator to predict the efficacy of this cotreatment.

The association of leptin and adiponectin with hepatocellular carcinoma risk and prognosis: a combination of traditional, survival, and dose-response meta-analysis

Background

An increasing number of studies have focused on the association between leptin, adiponectin levels and the risk as well as the prognosis of hepatocellular carcinoma. However, the reported results are conflicting.

Methods

A meta-analysis was performed to assess the correlation between leptin, adiponectin levels and risk and prognosis of hepatocellular carcinoma (CRD42020195882). Through June 14, 2020, PubMed, Cochrane Library and EMBASE databases were searched, including references of qualifying articles. Titles, abstracts, and main texts were reviewed by at least 2 independent readers. Stata 16.0 was used to calculate statistical data.

Results

Thirty studies were included in this meta-analysis and results showed that hepatocellular carcinoma group had significantly higher leptin levels than the cancer-free control group (SMD = 1.83, 95% CI (1.09, 2.58), P = 0.000), the healthy control group (SMD = 4.32, 95% CI (2.41, 6.24), P = 0.000) and the cirrhosis group (SMD = 1.85, 95% CI (0.70, 3.01), P = 0.002). Hepatocellular carcinoma group had significantly higher adiponectin levels than the healthy control group (SMD = 1.57, 95% CI (0.37, 2.76), P = 0.010), but no statistical difference compared with the cancer-free control group (SMD = 0.24, 95% CI (− 0.35, 0.82), P = 0.430) and the cirrhosis group (SMD = − 0.51, 95% CI (− 1.30, 0.29), P = 0.213). The leptin rs7799039 polymorphism was associated with increased risk of hepatocellular carcinoma (G vs A: OR = 1.28, 95% CI (1.10, 1.48), P = 0.002). There were linear relationships between adiponectin levels and the risk of hepatocellular carcinoma (OR = 1.066, 95% CI (1.03, 1.11), P = 0.001). In addition, the results showed that high/positive expression of adiponectin was significantly related to lower overall survival in hepatocellular carcinoma patients (HR = 1.70, 95% CI (1.22, 2.37), P = 0.002); however, there was no significantly association between the leptin levels and overall survival (HR = 0.92, 95% CI (0.53, 1.59), P = 0.766).

Conclusion

The study shows that high leptin levels were associated with a higher risk of hepatocellular carcinoma. Adiponectin levels were proportional to hepatocellular carcinoma risk, and were related to the poor prognosis.

Advances in Molecular Classification and Therapeutic Opportunities in Meningiomas

PURPOSE OF REVIEW

Our understanding of the genetic and epigenetic alterations in meningioma and the underlying tumor biology of meningioma has significantly changed over the past decade and resulted in revision of prognostically relevant meningioma subclasses within and beyond the WHO classification of CNS tumors.

RECENT FINDINGS

The 2016 WHO classification of CNS tumors recognizes WHO grade I, II, and III based on histopathological features. Recent work has identified genetic alterations with prognostic implications, including mutations of the TERT promoter, loss of function of the DMD gene, and inactivation of the tumor suppressor BAP-1. Studies of DNA methylation patterns in meningiomas have resulted in a novel and prognostically relevant meningioma subclassification schema. There have been major advances in our understanding of prognostically relevant genetic and epigenetic changes in meningioma which will hopefully allow for improvement in clinical trial design and the development of more effective therapies for meningioma.

Integrated Transcriptomic Analysis Reveals the Molecular Mechanism of Meningiomas by Weighted Gene Coexpression Network Analysis

Meningiomas are the most common primary intracranial tumor in adults. However, to date, systemic coexpression analyses for meningiomas fail to explain its pathogenesis. The aim of the present study was to construct coexpression modules and identify potential biomarkers associated with meningioma progression. Weighted gene coexpression network analysis (WGCNA) was performed based on GSE43290, and module preservation was tested by GSE74385. Functional annotations were performed to analyze biological significance. Hub genes were selected for efficacy evaluations and correlation analyses using two independent cohorts. A total of 14 coexpression modules were identified, and module lightcyan was significantly associated with WHO grades. Functional enrichment analyses of module lightcyan were associated with tumor pathogenesis. The top 10 hub genes were extracted. Ten biomarkers, particularly AHCYL2, FGL2, and KCNMA1, were significantly related to grades and prognosis of meningioma. These findings not only construct coexpression modules leading to the better understanding of its pathogenesis but also provide potential biomarkers that represent specific on tumor grades and identify recurrence, predicting prognosis and progression of meningiomas.

Meningioma: Signaling pathways and tumor growth

Meningiomas are the most common primary intracranial brain tumor in adult humans; however, our understanding of meningioma tumorigenesis is relatively limited in comparison with the body of research available for other intracranial tumors such as gliomas. Here we briefly describe the current understanding of aberrant signaling pathways and tumor growth mechanisms responsible for meningioma differentiation, cellular growth, development, inhibition, and death. Numerous cellular functions impacted by these signaling pathways are critical for angiogenesis, proliferation, and apoptosis. Ultimately, a further understanding of the signaling pathways involved in meningioma tumorigenesis will lead to better treatment modalities in the future.

Low Expression of Phosphatase and Tensin Homolog and High Expression of Ki-67 as Risk Factors of Prognosis in Cranial Meningiomas

OBJECTIVE

To investigate the expression characteristics, correlations with clinical factors, and prognostic values of phosphatase and tensin homolog (PTEN) and Ki-67 in cranial meningiomas.

METHODS

The expression of PTEN and Ki-67 at the mRNA level was analyzed in 34 frozen meningiomas. Clinical data collection, follow-up, correlations, and survival analyses were performed.

RESULTS

Twenty-two men and 12 women were included in the study, with a median age of 52.72 ± 11.72 years on admission. The average expression levels of PTEN and Ki-67 were 2.71 ± 1.73 and 0.50 ± 0.57, respectively. The World Health Organization grade III meningiomas exhibited significantly lower levels of PTEN (P = 0.037), whereas grade I meningiomas expressed significantly lower levels of Ki-67 (P = 0.001). For recurrent lesions, the mean Ki-67 expression level was 0.97 ± 0.76, which was significantly greater than that of primary meningiomas with a mean value of 0.25 ± 0.13 (P < 0.001). The Ki-67 expression level was positively correlated with the tumor volume (P < 0.01) and negatively correlated with preoperative Karnofsky Performance Status scale (KPS, P < 0.01), postoperative KPS (P < 0.05), and follow-up KPS (P < 0.01). However, the PTEN expression level did not correlate with these variables. Based on the multivariate Cox analysis, Ki-67 expression level (P < 0.001, hazard ratio [HR] 8.16, 95% confidence interval [CI] 2.86-23.29), and PTEN expression level (P = 0.018, HR 0.47, 95% CI 0.25-0.88) were independent prognostic factors for tumor recurrence. Ki-67 (P = 0.001, HR 19.73, 95% CI 3.65-106.61) and PTEN expression levels (P = 0.024, HR 0.36, 95% CI 0.15-0.88) were also independent prognostic factors for mortality.

CONCLUSIONS

A low PTEN expression and a high Ki-67 expression could predict malignancy in cranial meningiomas.

A Comprehensive Review on MAPK: A Promising Therapeutic Target in Cancer

The mitogen-activated protein kinase (MAPK) pathway is an important bridge in the switch from extracellular signals to intracellular responses. Alterations of signaling cascades are found in various diseases, including cancer, as a result of genetic and epigenetic changes. Numerous studies focused on both the homeostatic and the pathologic conduct of MAPK signaling; however, there is still much to be deciphered in terms of regulation and action models in both preclinical and clinical research. MAPK has implications in the response to cancer therapy, particularly the activation of the compensatory pathways in response to experimental MAPK inhibition. The present paper discusses new insights into MAPK as a complex cell signaling pathway with roles in the sustenance of cellular normal conduit, response to cancer therapy, and activation of compensatory pathways. Unfortunately, most MAPK inhibitors trigger resistance due to the activation of compensatory feed-back loops in tumor cells and tumor microenvironment components. Therefore, novel combinatorial therapies have to be implemented for cancer management in order to restrict the possibility of alternative pathway activation, as a perspective for developing novel therapies based on integration in translational studies.

Nucleotide variations of TP53 exon 4 found in intracranial meningioma and in silico prediction of their significance

The aim of the present study was to identify TP53 exon 4 mutations in patients with meningioma and to investigate their potential association with specific tumor pathology. Nucleotide alterations were investigated in 48 meningiomas via the direct sequencing of TP53 exon 4 in patient tumor and blood samples using the DNA Sanger method with the BigDyeTerminator v3.1 Cycle Sequencing kit and Applied Biosystems 3730XL apparatus. The results revealed that TP53 exon 4 was frequently altered in meningioma, occurring in 60.4% of the patients investigated. A total of 18 different alterations were detected in the meningioma samples assessed in the current study. The majority of these appeared more than once and some were repeatedly identified in several patients. Changes at codons 72 (c.215G>C) and 62 (c.186delA) were highly prevalent, occurring in 44.8% of patients. Other changes detected via frequency analysis included: Five substitutions on codon 105 (c.315C>T); four insertions on codon 70 (c.209_210insG); three insertions on codon 64 (c.190C>G), 82 (245C>T; 245delC; 243_244insA) and 104 (c.312G>A); and two insertions on codons 108 (c.322G>C), 71 (c.213C>A), 73 (c.217G>A), 91 (c.271T>C) and 100 (c.300G>T). Codons 68 (c.202_203insT), 77 (c.229C>T), 88 (c.263C>G) and 92 (c.276C>A) were altered once. Alterations on codons 82, 91, 108, 104, 105, 70 and 92 were characterized as possibly damaging by PolyPhen-2 and Mutation Taster2 tools. The current study also demonstrated that nucleotide alterations were significantly associated with the loss of p53 expression (P=0.04) and female patients (P=0.049), particularly codon 72. The results present novel data on the mutational spectrum of TP53 in meningeal brain tumors.

Comparative Tumor RNA Sequencing Analysis for Difficult-to-Treat Pediatric and Young Adult Patients With Cancer

IMPORTANCE

Pediatric cancers are epigenetic diseases; therefore, considering tumor gene expression information is necessary for a complete understanding of the tumorigenic processes.

OBJECTIVE

To evaluate the feasibility and utility of incorporating comparative gene expression information into the precision medicine framework for difficult-to-treat pediatric and young adult patients with cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted as a consortium between the University of California, Santa Cruz (UCSC) Treehouse Childhood Cancer Initiative and clinical genomic trials. RNA sequencing (RNA-Seq) data were obtained from the following 4 clinical sites and analyzed at UCSC: British Columbia Children's Hospital (n = 31), Lucile Packard Children's Hospital at Stanford University (n = 80), CHOC Children's Hospital and Hyundai Cancer Institute (n = 46), and the Pacific Pediatric Neuro-Oncology Consortium (n = 24). The study dates were January 1, 2016, to March 22, 2017.

EXPOSURES

Participants underwent tumor RNA-Seq profiling as part of 4 separate clinical trials at partner hospitals. The UCSC either downloaded RNA-Seq data from a partner institution for analysis in the cloud or provided a Docker pipeline that performed the same analysis at a partner institution. The UCSC then compared each participant's tumor RNA-Seq profile with more than 11 000 uniformly analyzed tumor profiles from pediatric and young adult patients with cancer, downloaded from public data repositories. These comparisons were used to identify genes and pathways that are significantly overexpressed in each patient's tumor. Results of the UCSC analysis were presented to clinical partners.

MAIN OUTCOMES AND MEASURES

Feasibility of a third-party institution (UCSC Treehouse Childhood Cancer Initiative) to obtain tumor RNA-Seq data from patients, conduct comparative analysis, and present analysis results to clinicians; and proportion of patients for whom comparative tumor gene expression analysis provided useful clinical and biological information.

RESULTS

Among 144 samples from children and young adults (median age at diagnosis, 9 years; range, 0-26 years; 72 of 118 [61.0%] male [26 patients sex unknown]) with a relapsed, refractory, or rare cancer treated on precision medicine protocols, RNA-Seq-derived gene expression was potentially useful for 99 of 144 samples (68.8%) compared with DNA mutation information that was potentially useful for only 34 of 74 samples (45.9%).

CONCLUSIONS AND RELEVANCE

This study's findings suggest that tumor RNA-Seq comparisons may be feasible and highlight the potential clinical utility of incorporating such comparisons into the clinical genomic interpretation framework for difficult-to-treat pediatric and young adult patients with cancer. The study also highlights for the first time to date the potential clinical utility of harmonized publicly available genomic data sets.

Histomolecular characterization of intracranial meningiomas developed in patients exposed to high-dose cyproterone acetate: an antiandrogen treatment

Background

Meningiomas are the most common primary intracranial tumors in adults. The relationship between meningiomas and exogenous sex hormones such as cyproterone acetate (CPA) is well documented, yet the underlying mechanisms remain unknown. Defining the histomolecular status of meningiomas developed on CPA would help us to better understand the oncogenesis of these tumors.

Methods

We identified 30 patients operated for a meningioma after long-term high-dose CPA therapy and with a history of CPA discontinuation before establishing the indication for surgical intervention. We used array-comparative genomic hybridization (to characterize copy number changes in those 30 meningiomas and subsequently performed next-generation sequencing with the National Institute of Cancer (INCa) solid tumor panel, which is a targeted panel of clinically actionable genes. We also examined grade, type, and clinical features.

Results

We identified AKT1 mutations or PIK3CA mutations in 33.3% of CPA meningiomas. AKT1 and PIK3CA mutations were mutually exclusive. Enrichment in oncogenic PIK3CA mutations in the CPA cohort was detected. CPA meningiomas showed chromosomal stability and were located mainly in the skull base. Ninety percent of CPA meningiomas were low-grade meningiomas and 63.4% were meningotheliomas. Half of our CPA cohort had microcystic components.

Conclusion

Our study shows that low-grade meningothelial meningiomas of the skull base are predominant in CPA meningiomas. We identified PIK3CA/AKT1 pathway as a hypothetical actor in onco-pharmacological interaction between meningiomas and CPA. This signaling pathway could be an interesting target for precision medicine trials in meningioma patients who have been subjected to CPA. Our results could invite the scientific community to review the current classification of meningiomas and to evolve toward more specific histomolecular classification.

IRF2-INPP4B-mediated autophagy suppresses apoptosis in acute myeloid leukemia cells

Background

The present study aimed to investigate the underlying role of interferon-regulatory factor 2 (IRF2)–inositol polyphosphate-4-phosphatase, type-II (INPP4B) axis in the regulation of autophagy in acute myeloid leukemia (AML) cells.

Methods

Quantitative real time PCR (QRT-PCR) and western blot were performed to determine the expression levels of IRF2, INPP4B and autophagy-related markers in AML cell lines. Autophagy was assessed by elevated Beclin-1 expression, the conversion of light chain 3 (LC3)-I to LC3-II, downregulated p62 expression and green fluorescent protein (GFP)-LC3 puncta formation. The colony formation and apoptosis assays were performed to determine the effects of IRF2 and INPP4B on the growth of AML cells.

Results

IRF2 and INPP4B were highly expressed in AML cell lines, and were positively correlated with autophagy-related proteins. Overexpression of IRF2 or INPP4B stimulated autophagy of AML cells, whereas inhibition of IRF2 or INPP4B resulted in the attenuation of autophagy. More importantly, IRF2 or INPP4B overexpression reversed autophagy inhibitor, 3-methyladenine (3-MA)-induced proliferation-inhibitory and pro-apoptotic effects, while IRF2 or INPP4B silencing overturned the proliferation-promoting and anti-apoptotic effects of autophagy activator rapamycin.

Conclusion

IRF2–INPP4B signaling axis attenuated apoptosis through induction of autophagy in AML cells.

Drosophila melanogaster: A Model Organism to Study Cancer

Cancer is a multistep disease driven by the activation of specific oncogenic pathways concomitantly with the loss of function of tumor suppressor genes that act as sentinels to control physiological growth. The conservation of most of these signaling pathways in Drosophila, and the ability to easily manipulate them genetically, has made the fruit fly a useful model organism to study cancer biology. In this review we outline the basic mechanisms and signaling pathways conserved between humans and flies responsible of inducing uncontrolled growth and cancer development. Second, we describe classic and novel Drosophila models used to study different cancers, with the objective to discuss their strengths and limitations on their use to identify signals driving growth cell autonomously and within organs, drug discovery and for therapeutic approaches.

High p-mTOR expression is associated with recurrence and shorter disease-free survival in atypical meningiomas

Due to their widely variable clinical behavior, the post-surgical treatment of atypical meningiomas is controversial. Therefore, prognostic factors able to identify high-risk cases, which may benefit from adjuvant treatments, are warranted. Mammalian target of rapamycin (mTOR) belongs to the PI3K-AKT pathway. Its phosphorylated form (p-mTOR Ser2448) is involved in cell growth, differentiation and tumorigenesis. The aim of this study was to evaluate p-mTOR Ser2448 expression and its eventual correlation with clinicopathological features, recurrence, or disease-free survival (DFS), in atypical meningiomas. p-mTOR immunohistochemical expression was analyzed in 48 atypical meningiomas and correlated with clinicopathological parameters and with DFS. Eighty-one percent of atypical meningiomas expressed p-mTOR Ser2448. High immuno-expression was significantly associated with recurrences (P = 0.01) and lower DFS (P = 0.01). The presence of brain invasion, high mitotic index plus sheeting, and Simpson grade were significant and independent prognostic variables at multivariate analysis. p-mTOR Ser2448 is expressed in atypical meningiomas. High expression predicts development of recurrences and shorter DFS in patients affected by these tumors. Since p-mTOR Ser2448 is a target of anti-neoplastic drugs, evaluation of its expression may be used, not only to identify atypical meningiomas at higher risk of recurrence, but also to select those to submit to adjuvant targeted chemotherapy.

Investigation of LEP and LEPR polymorphisms with the risk of hepatocellular carcinoma: a case-control study in Eastern Chinese Han population

Background

Leptin (LEP) and LEP receptor (LEPR) polymorphisms may be associated with the development of cancer.

Methods

In this study, we selected five functional LEP and LEPR single-nucleotide polymorphisms (SNPs) and conducted a case–control study to determine the relationship of LEP and LEPR polymorphisms with hepatocellular carcinoma (HCC) risk in Eastern Chinese Han population. There were 584 HCC cases and 923 cancer-free controls included in our study. HCC patients and controls were fully matched by age and sex. SNPscan™ genotyping method was used to analyze the genotyping of LEP rs2167270 G>A, rs7799039 A>G, LEPR rs6588147 G>A, rs1137100 G>A, and rs1137101 G>A SNPs.

Results

We found that LEP rs7799039 A>G and rs2167270 G>A polymorphisms were associated with the susceptibility of HCC in this population (LEP rs7799039 A>G: GG vs AA: adjusted odds ratio [OR]=2.03, 95% CI, 1.22–3.38, P=0.006 and GG vs AA/AG: adjusted OR=1.97, 95% CI, 1.20–3.22, P=0.007; rs2167270 G>A: AA vs GG: adjusted OR=2.03, 95% CI, 1.10–3.75, P=0.024 and AA vs GG/GA: adjusted OR=2.01, 95% CI, 1.10–3.68, P=0.023). However, LEPR rs6588147 G>A polymorphism decreased the risk of HCC (GA vs GG: adjusted OR=0.62, 95% CI, 0.45–0.86, P=0.005 and AA/GA vs GG: adjusted OR=0.64, 95% CI, 0.47–0.88, P=0.007).

Conclusion

This case–control study highlights that LEP rs7799039 A>G and rs2167270 G>A polymorphisms increase the susceptibility to HCC; however, LEPR rs6588147 G>A polymorphism may be a protective factor for HCC in Eastern Chinese Han population.

Advances in meningioma genetics: novel therapeutic opportunities

Meningiomas currently are among the most frequent intracranial tumours. Although the majority of meningiomas can be cured by surgical resection, ∼20% of patients have an aggressive clinical course with tumour recurrence or progressive disease, resulting in substantial morbidity and increased mortality of affected patients. During the past 3 years, exciting new data have been published that provide insights into the molecular background of meningiomas and link sites of tumour development with characteristic histopathological and molecular features, opening a new road to novel and promising treatment options for aggressive meningiomas. A growing number of the newly discovered recurrent mutations have been linked to a particular clinicopathological phenotype. Moreover, the updated WHO classification of brain tumours published in 2016 has incorporated some of these molecular findings, setting the stage for the improvement of future therapeutic efforts through the integration of essential molecular findings. Finally, an additional potential classification of meningiomas based on methylation profiling has been launched, which provides clues in the assessment of individual risk of meningioma recurrence. All of these developments are creating new prospects for effective molecularly driven diagnosis and therapy of meningiomas.

Meta-analysis of the prognostic value of p-4EBP1 in human malignancies

Phosphorylated 4E-binding protein 1 (p-4EBP1) is the inactivated form of 4EBP1, which is a downstream mediator in the mTOR signaling pathway and a vital factor in the synthesis of some oncogenic proteins. This meta-analysis was conducted to assess the predicative value of p-4EBP1 expression in human malignancies. The PubMed and Embase databases were carefully searched. Articles comparing the prognostic worthiness of different p-4EBP1 levels in human malignancies were collected for pooled analyses and methodologically appraised using the Newcastle-Ottawa Scale (NOS). A total of 39 retrospective cohorts with an overall sample size of 3,980 were selected. Patients with lower p-4EBP1 expression had better 3-year (P < 0.00001), 5-year (P < 0.00001), and 10-year (P = 0.03) overall survival and better 3-year (P < 0.0001) and 5-year (P = 0.0005) disease-free survival. Subgroup analyses confirmed the unfavorable prognosis associated with p-4EBP1 overexpression. These findings were further validated by sensitivity analyses. Harbord and Peters tests revealed no publication bias within the included studies. It thus appears higher expression of p-4EBP1 indicates a poor prognosis in human malignancies.

Knockdown of lncRNA HULC inhibits proliferation, migration, invasion, and promotes apoptosis by sponging miR-122 in osteosarcoma

Osteosarcoma is a rare malignant bone tumor with high degree of malignancy. HULC (highly upregulated in liver cancer), a long noncoding RNA (lncRNA) was involved in hepatocellular carcinoma development and progression, but its underlying mechanism in osteosarcoma is unknown. The aim of this study was to explore the functional role of HULC in osteosarcoma. The study was conducted in human osteosarcoma cell lines and the expression of HULC in the cell lines was detected by qRT-PCR. Furthermore, the effects of HULC on tumorigenicity of osteosarcoma cells were evaluated by in vitro assays. Results revealed that HULC was highly expressed in osteosarcoma MG63 and OS-732 cells compared to osteoblast hFOB1.19 cells. Suppression of HULC in osteosarcoma cells inhibited cell viability, migration, invasion, and promoted apoptosis. HULC functioned as an endogenous sponge for miR-122, and its silence functioned through upregulating miR-122. HNF4G was a target of miR-122, and the effect of HNF4G on OS-732 cells was the same as HULC. Furthermore, overexpression of miR-122 inactivated PI3K/AKT, JAK/STAT, and Notch pathways by downregulation of HNF4G. These findings suggest that knockdown of HULC inhibited proliferation, migration, and invasion by sponging miR-122 in osteosarcoma cells. HULC may act as a novel therapeutic target for management of osteosarcoma.

Alpha-synuclein contributes to malignant progression of human meningioma via the Akt/mTOR pathway

BACKGROUND

The aim of this study is to explore the expression of alpha-synuclein (α-synuclein) in benign, atypical, and anaplastic meningiomas and determine its role in the malignant progression of meningiomas.

METHODS

Expression of α-synuclein was measured in 44 meningioma samples by real-time PCR analysis. The effects of overexpression or knockdown of α-synuclein on meningioma cell growth, invasiveness, and tumorigenicity were determined.

RESULTS

Atypical and anaplastic meningiomas displayed significantly greater levels of α-synuclein mRNA, relative to benign tumors. Depletion of α-synuclein decreased cell proliferation and colony formation and promoted apoptosis in IOMM-Lee meningioma cells, whereas overexpression of α-synuclein facilitated cell proliferation and colony formation in CH-157MN meningioma cells. Silencing of α-synuclein attenuated IOMM-Lee cell migration and invasion. In contrast, ectopic expression of α-synuclein increased the invasiveness of CH-157MN cells. In vivo studies further demonstrated that downregulation of α-synuclein significantly retarded meningioma growth in nude mice. At the molecular level, the phosphorylation levels of Akt, mTOR, p70S6K and 4EBP were significantly decreased in α-synuclein-depleted IOMM-Lee cells.

CONCLUSIONS

In conclusion, α-synuclein upregulation contributes to aggressive phenotypes of meningiomas via the Akt/mTOR pathway and thus represents a potential therapeutic target for malignant meningiomas.

Somatic AKT1 mutations cause meningiomas colocalizing with a characteristic pattern of cranial hyperostosis

Somatic genetic mutations in meningiomas are associated with histologic subtypes, anatomical location, and grade. Concomitant hyperostosis occurs with some meningiomas and the pathogenesis is not well understood. Cranial hyperostosis and meningiomas are common in patients with Proteus syndrome, which is caused by a somatic activating mutation in AKT1 c.49G>A. This same mutation has also been found in 6-9% of sporadic non-syndromic meningiomas. Sixty-one patients with Proteus syndrome meeting clinical diagnostic criteria were evaluated at the NIH from 1997 to 2014. Of these 61, 52 had a somatic activating mutation (c.49G>A, p.Glu17Lys) in AKT1 confirmed from affected tissue samples. Photographs, physical examination and/or autopsy, X-rays, CT, and/or MRI scan of the head were reviewed in 29/52 patients. Of the 29 patients, the most common intracranial tumor was meningioma, all co-localizing with cranial hyperostosis, and diagnosed at younger ages than typical for isolated, non-syndromic meningiomas. These patients had progressive cranial overgrowth that consisted primarily of diploic space expansion, and was characterized by unilateral, parasagittal, and frontal bone involvement. We hypothesize that sporadic meningothelial and transitional subtype meningiomas are a forme fruste or microform of Proteus syndrome, and activation of the AKT/PI3K pathway drives hyperostosis in both non-syndromic, and Proteus-related meningiomas. © 2016 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc.

Multiple Meningiomas in a Patient with Cowden Syndrome

BACKGROUND

Cowden syndrome is a rare, multisystem disease manifesting with increased hamartomas and neoplasms. Though meningioma has been documented in patients with Cowden syndrome, the relationship between these two phenomena is still unclear.

CASE DESCRIPTION

We report a case of a 43-year-old female patient with a known PTEN mutation and clinical history of Cowden syndrome. A workup of headache demonstrated two skull base meningiomas. At the time of surgery, several additional tiny meningiomas were detected in the same region.

CONCLUSIONS

The development of multiple meningiomas in a patient with predisposition for tumor is more than coincidental. Though PTEN mutations and deletions have not been shown to be critical for meningioma development, this case challenges that conclusion. In light of recent genetic advances in meningioma molecular pathogenesis, the role of the PTEN/AKT/PI3K pathway is discussed.

Loss of p53 expression is accompanied by upregulation of beta-catenin in meningiomas: a concomitant reciprocal expression

Crosstalk between Wnt and p53 signalling pathways in cancer has long been suggested. Therefore in this study we have investigated the involvement of these pathways in meningiomas by analysing their main effector molecules, beta-catenin and p53. Cellular expression of p53 and beta-catenin proteins and genetic changes in TP53 were analysed by immunohistochemistry, PCR/RFLP and direct sequencing of TP53 exon 4. All the findings were analysed statistically. Our analysis showed that 47.5% of the 59 meningiomas demonstrated loss of expression of p53 protein. Moderate and strong p53 expression in the nuclei was observed in 8.5% and 6.8% of meningiomas respectively. Gross deletion of TP53 gene was observed in one meningioma, but nucleotide alterations were observed in 35.7% of meningiomas. In contrast, beta-catenin, the main Wnt signalling molecule, was upregulated in 71.2%, while strong expression was observed in 28.8% of meningiomas. The concomitant expressions of p53 and beta-catenin were investigated in the same patients. In the analysed meningiomas, the levels of the two proteins were significantly negatively correlated (P = 0.002). This indicates that meningiomas with lost p53 upregulate beta-catenin and activate Wnt signalling. Besides showing the reciprocal relationship between proteins, we also showed that the expression of p53 was significantly (P = 0.021) associated with higher meningioma grades (II and III), while beta-catenin upregulation was not associated with malignancy grades. Additionally, women exhibited significantly higher values of p53 loss when compared to males (P = 0.005). Our findings provide novel information about p53 involvement in meningeal brain tumours and reveal the complex relationship between Wnt and p53 signalling, they suggest an important role for beta-catenin in these tumours.

Differentially Expressed MicroRNAs in Meningiomas Grades I and II Suggest Shared Biomarkers with Malignant Tumors

Meningiomas represent the most common primary tumors of the central nervous system, but few microRNA (miRNA) profiling studies have been reported so far. Deep sequencing of small RNA libraries generated from two human meningioma biopsies WHO grades I (benign) and II (atypical) were compared to excess dura controls. Nineteen differentially expressed miRNAs were validated by RT-qPCR using tumor RNA from 15 patients and 5 meninges controls. Tumor suppressor miR-218 and miR-34a were upregulated relative to normal controls, however, miR-143, miR-193b, miR-451 and oncogenic miR-21 were all downregulated. From 10 selected putative mRNA targets tested by RT-qPCR only four were differentially expressed relative to normal controls. PTEN and E-cadherin (CDH1) were upregulated, but RUNX1T1 was downregulated. Proliferation biomarker p63 was upregulated with nuclear localization, but not detected in most normal arachnoid tissues. Immunoreactivity of E-cadherin was detected in the outermost layer of normal arachnoids, but was expressed throughout the tumors. Nuclear Cyclin D1 expression was positive in all studied meningiomas, while its expression in arachnoid was limited to a few trabecular cells. Meningiomas of grades I and II appear to share biomarkers with malignant tumors, but with some additional tumor suppressor biomarkers expression. Validation in more patients is of importance.

Corilagin suppresses cholangiocarcinoma progression through Notch signaling pathway in vitro and in vivo

Corilagin is a natural plant polyphenol tannic acid with antitumor, anti-inflammatory, and anti-oxidative properties. However, the mechanisms of its actions are largely unknown. Our group reported that corilagin could induce cell inhibition in human breast cancer cell line MCF-7 and human liver hepatocellular carcinoma cell lines HepG2. We report here that corilagin inhibits cholangiocarcinoma (CCA) development through regulating Notch signaling pathway. We found that, in vitro, corilagin inhibited CCA cell proliferation, migration and invasion, promoted CCA cell apoptosis, and inhibited Notch1 and Notch signaling pathway protein expression. Co-immunoprecipitation was used to establish Notch intracellular domain (NICD) interaction with MAML1 and P300 in CCA. Importantly, corilagin reduced Hes1 mRNA level through inhibiting Hes1 promoter activity. In nude mice, corilagin inhibited CCA growth and repressed the expression of Notch1 and mTOR. These results indicate that corilagin may control CCA cell growth by downregulating the expression of Notch1. Therefore, our findings suggest that corilagin may have the potential to become a new therapeutic drug for human CCA.

Oncogenic PI3K mutations are as common as AKT1 and SMO mutations in meningioma

BACKGROUND

Meningiomas are the most common primary intracranial tumor in adults. Identification of SMO and AKT1 mutations in meningiomas has raised the possibility of targeted therapies for some patients. The frequency of such mutations in clinical cohorts and the presence of other actionable mutations in meningiomas are important to define.

METHODS

We used high-resolution array-comparative genomic hybridization to prospectively characterize copy-number changes in 150 meningiomas and then characterized these samples for mutations in AKT1, KLF4, NF2, PIK3CA, SMO, and TRAF7.

RESULTS

Similar to prior reports, we identified AKT1 and SMO mutations in a subset of non-NF2-mutant meningiomas (ie, ∼9% and ∼6%, respectively). Notably, we detected oncogenic mutations in PIK3CA in ∼7% of non-NF2-mutant meningiomas. AKT1, SMO, and PIK3CA mutations were mutually exclusive. AKT1, KLF4, and PIK3CA mutations often co-occurred with mutations in TRAF7. PIK3CA-mutant meningiomas showed limited chromosomal instability and were enriched in the skull base.

CONCLUSION

This work identifies PI3K signaling as an important target for precision medicine trials in meningioma patients.

Immunohistochemical and molecular analysis of PI3K/AKT/mTOR pathway in esophageal carcinoma

Among the numerous signaling pathways involved in tumorigenesis, PI3K-AKT-mTOR is a key one that regulates diverse cellular functions. However, its prognostic value in esophageal carcinoma remains unclear. In our study, we examined the immunohistochemical expression of phosphorylated (p-) AKT, mTOR, p70S6K and 4E-BP1 along with the mutational status of PIK3CA and AKT1 genes by High Resolution Melting Analysis and Pyrosequencing in 44 esophageal carcinomas. The results were correlated with the clinicopathological characteristics of the patients in an effort to define their possible prognostic significance. Total p-mTOR cytoplasmic expression, assessed in 10 random areas, was positively correlated with tumor stage (Kruskal-Wallis ANOVA, I/II vs III/IV, p = 0.0500). Μoreover, maximum p-mTOR cytoplasmic immunoexpression, estimated in hot spot areas, was positively associated with tumor grade (Mann-Whitney U test, I/II vs III, p = 0.0565). Interestingly, p-4E-BP1 immunoreactivity was negatively correlated with tumor histological grade (Mann-Whitney U test, I/II vs III, p = 0.0427). No mutation was observed in exons 9 and 20 of PIK3CA gene and in exon 4 of AKT1 gene. In conclusion, our findings depict the presence of activated PI3K/AKT/mTOR pathway in esophageal cancer bringing forward p-mTOR and p-4E-BP1 for their potential role in esophageal carcinogenesis. Additional studies are warranted to validate our findings.

Icariin induces osteogenic differentiation of bone mesenchymal stem cells in a MAPK-dependent manner

OBJECTIVES

Icariin, a flavonoid isolated from Epimedium pubescens, has previously been identified to exert beneficial effects on preventing bone loss and promoting bone regeneration. However, molecular mechanisms for its anabolic action have, up to now, remained largely unknown.

MATERIALS AND METHODS

Effects of icariin on cell proliferation and osteogenic differentiation of rat bone mesenchymal stem cells (BMSCs) were systematically evaluated. To characterize underlying mechanisms, its effects on mitogen-activated protein kinase (MAPK) signalling pathways were determined.

RESULTS

Results showed that icariin might not have enhanced effects on cell proliferation. However, it seemed to significantly enhance osteogenic differentiation of BMSCs, demonstrated by increasing alkaline phosphatase (ALP) activity and gene expression of collagen type I (Col I), osteocalcin (OCN) and osteopotin (OPN). It was demonstrated that icariin rapidly phosphorylated extracellular signal-regulated kinase (ERK), p38 kinase and c-Jun N terminal kinase (JNK). Furthermore, icariin-stimulated osteogenic effects on BMSCs were dramatically attenuated by treatment with either specific ERK inhibitor of PD98059, p38 inhibitor of SB202190 or JNK inhibitor SP600125.

CONCLUSIONS

These results provide a potential mechanism of anabolic activity of icariin on BMSCs involving ERK, p38 and JNK MAPK pathways.