Unraveling the Impact of miRNA-17 in Glial Tumors and Cerebral Metastases: A Step Towards Enhanced Diagnosis and Prognosis

BACKGROUND/AIM

MicroRNAs (miRNAs) have been identified as key regulators in various cancer types, including brain tumors. This study aimed to investigate the differential expression of miRNA-17 in glial tumors, cerebral metastases, and normal glial tissues.

MATERIALS AND METHODS

A total of 42 patients were included in this cross-sectional study. Tissue samples were obtained from patients with glial tumors or cerebral metastases and from normal glial tissues. miRNA-17 expression levels were computed by using real-time polymerase chain reaction. Receiver operating characteristics analysis was used to determine the predictive potential of miRNA-17.

RESULTS

In this study, we demonstrated a statistically significant difference in miRNA-17 expression levels between glial tumors and the control group (p=0.001), with higher miRNA-17 expression observed in glial tumors. Similarly, there was statistically higher miRNA-17 expression in metastatic cases compared with the control group (p=0.007).

CONCLUSION

These findings suggest miRNA-17 might be a potential biomarker for differentiating glial tumors and cerebral metastases from normal glial tissue, although further research is necessary to validate these findings and investigate the potential role of miRNA-17 in the pathogenesis of these brain tumors.

Expression of miRNA-451 and miRNA-885 in Meningiomas

BACKGROUND/AIM

Meningiomas are one of the most common intracranial tumors, accounting for 30% of the tumors of the central nervous system. MicroRNAs (miRNAs) are noncoding RNAs containing approximately 18-22 nucleotides that regulate gene expression by interfering with transcription or inhibiting translation. Recent studies have reported that miRNAs could provide information about the molecular pathogenesis of several types of tumors. This study aimed to examine the expression levels of miRNA-885 and -451 and to determine their potential roles as biomarkers in meningioma.

MATERIALS AND METHODS

In total, 29 patients with meningioma (9 males and 20 females) were included in this study. The expression levels of miRNA were determined using real-time polymerase chain reaction. In addition, receiver operating characteristic curve analysis was used to analyze the predictive potential of miRNAs.

RESULTS

Our results indicated a significant increase in miRNA-451 expression levels (p=0.003); however, there was no significant change in miRNA-885 expression levels (p=0.139) in patients with meningioma compared with the control group. Moreover, miRNA-885 and miRNA-451 expression levels did not differ significantly based on the histopathological grade of meningioma.

CONCLUSION

miRNA-451 may be a novel potential marker for the diagnosis and prognosis, and a target for meningioma treatment.

Peritumoural Oedema as a Predictor of Overall Survival for Patients with Posterior Fossa Metastases

OBJECTIVE

To analyse the relationship between peritumoural oedema volume and tumour volume in relation to the impact of metastatic posterior fossa tumour survival rates.

STUDY DESIGN

An observational study.

PLACE AND DURATION OF STUDY

Umraniye Training and Research Hospital, İstanbul, Turkey, from 2011-2021.

METHODOLOGY

Fifty-six cancer patients who had been operated upon for cerebellar metastases were analysed retrospectively. To investigate the effect of oedema on survival, patients with a single cerebellar metastasis were evaluated retrospectively. Those patients had a single metastasis located in the cerebellum and did not receive radiotherapy or corticosteroids before surgery. OsiriX MD DICOM viewer was used to calculate the volumes of the tumour and the oedema using fluid-attenuated inversion recovery (FLAIR) and contrast-enhanced magnetic resonance imaging (MRI). The patients were separated into two groups, and the cut-off limit for the oedema to-tumour ratio was set to two. Survival analysis was performed on the two groups.

RESULTS

When the primary sites of the tumours were evaluated, 60.7% were located in the lungs (n = 34), 10.7% were located in the breasts (n = 6), 10.7% were located in the gastrointestinal tract (n = 6), 7.1% were located in the renal region (n = 4), 5.4% were located in the gynaecologic tract (n = 3), and 5.4% were located in other parts of the body (n = 3). A univariate analysis showed that overall survival duration was significantly longer in the subgroup with breast cancer (83.3%) and in those patients with a peritumoural oedema volume to tumour volume ratio of less than two (27.6%, p <0.05). Negative prognostic factors were lung cancer and high peritumoural oedema volume.

CONCLUSION

Significant peritumoural oedema was linked to a poor prognosis for cancer patients with a single cerebellar metastasis, especially with lung cancer as the primary source.

KEY WORDS

Cerebellar metastases, Cerebellum, OsiriX MD, Tumour volume.

Osteoplastic Pterional Craniotomy: Success Rate of Surgery in Patient Aspect

AIM

To evaluate the effect of osteoplastic pterional craniotomy on temporal hollowing and its sequelae.

MATERIAL AND METHODS

A total of 97 patients who underwent pterional craniotomy for an aneurysm were analyzed retrospectively. Of these 97 patients, 63 underwent surgery via the conventional pterional approach and 34 underwent surgery via the osteoplastic pterional approach. The temporal muscle volume was calculated bilaterally on CT images obtained in the sixth postoperative month. The results obtained in the conventional and osteoplastic approaches were compared.

RESULTS

Of the 97 included patients, 45 were female and 52 were male. The mean patient age was 50.37 years. In the conventional group, 31 were female and 32 were male. In the osteoplastic group, 14 were female and 20 were male. The temporal muscle volume difference between the operated and non-operated side was not statistically significant in the osteoplastic group. However, the volume was slightly lesser on the operated side than on the non-operated side in the conventional group.

CONCLUSION

The osteoplastic pterional approach is superior to the conventional approach in preserving the muscle volume and function. Patients who underwent osteoplastic craniotomy demonstrated higher levels of satisfaction with their facial appearance compared to those who underwent craniotomy using the conventional pterional approach.

Qlone®: A Simple Method to Create 360-Degree Photogrammetry-Based 3-Dimensional Model of Cadaveric Specimens

BACKGROUND

Human cadavers are an essential component of anatomy education. However, access to cadaveric specimens and laboratory facilities is limited in most parts of the world. Hence, new innovative approaches and accessible technologies are much needed to enhance anatomy training.

OBJECTIVE

To provide a practical method for 3-dimensional (3D) visualization of cadaveric specimens to maximize the utility of these precious educational materials.

METHODS

Embalmed cadaveric specimens (cerebrum, brain stem, and cerebellum) were used. The 3D models of cadaveric specimens were built by merging multiple 2-dimensional photographs. Pictures were taken with standard mobile devices (smartphone and tablet). A photogrammetry program (Qlone®, 2017-2020, EyeCue Vision Technologies Ltd, Yokneam, Israel), an all-in-one 3D scanning and augmented reality technology, was then used to convert the images into an integrated 3D model.

RESULTS

High-resolution 360-degree 3D models of the cadaveric specimens were obtained. These models could be rotated and moved freely on different planes, and viewed from different angles with varying magnifications. Advanced editing options and the possibility for export to virtual- or augmented-reality simulation allowed for better visualization.

CONCLUSION

This inexpensive, simple, and accessible method for creating 360-degree 3D cadaveric models can enhance training in neuroanatomy and allow for a highly realistic surgical simulation environment for neurosurgeons worldwide.

Hypothalamitis: A Novel Autoimmune Endocrine Disease. A Literature Review and Case Report

CONTEXT

The relationship between the endocrine system and autoimmunity has been recognized for a long time and one of the best examples of autoimmune endocrine disease is autoimmune hypophysitis. A better understanding of autoimmune mechanisms and radiological, biochemical, and immunological developments has given rise to the definition of new autoimmune disorders including autoimmunity-related hypothalamic-pituitary disorders. However, whether hypothalamitis may occur as a distinct entity is still a matter of debate.

EVIDENCE ACQUISITION

Here we describe a 35-year-old woman with growing suprasellar mass, partial empty sella, central diabetes insipidus, hypopituitarism, and hyperprolactinemia.

EVIDENCE SYNTHESIS

Histopathologic examination of surgically removed suprasellar mass revealed lymphocytic infiltrate suggestive of an autoimmune disease with hypothalamic involvement. The presence of antihypothalamus antibodies to arginine vasopressin (AVP)-secreting cells (AVPcAb) at high titers and the absence of antipituitary antibodies suggested the diagnosis of isolated hypothalamitis. Some similar conditions have sometimes been reported in the literature but the simultaneous double finding of lymphocytic infiltrate and the presence of AVPcAb so far has never been reported.

CONCLUSIONS

We think that the hypothalamitis can be considered a new isolated autoimmune disease affecting the hypothalamus while the lymphocytic infundibuloneurohypophysitis can be a consequence of hypothalamitis with subsequent autoimmune involvement of the pituitary. To our knowledge this is the first observation of autoimmune hypothalamic involvement with central diabetes insipidus, partial empty sella, antihypothalamic antibodies and hypopituitarism.

Investigation of the Effects of MicroRNA-221 Expression Levels in Glioblastoma Multiforme Tumors

BACKGROUND/AIM

The aim of our study was to examine miRNA-221 as a candidate biomarker to define prognosis and/or classification for glial tumors.

MATERIALS AND METHODS

This study included 39 patients who underwent glial tumor surgery and 40 healthy individuals as the control group. miRNA expression levels were determined by real-time polymerase chain reaction (RT-PCR). Receiver operating characteristic curve analysis was used for analyzing the predictive ability of miRNA-221.

RESULTS

The levels of miRNA-221 expression were determined by comparing the ΔCT values of miRNAs and the internal control. When the expression levels of miRNA-221 were compared according to the ΔCT method, miRNA-221 was found to be significantly increased in the patient group compared to the control group (p<0.0001).

CONCLUSION

Increased expression levels of miRNA-221 could be a biomarker for glial tumors.

The Use of Osirix for Surgical Planning Using Cranial Measures and Region of Interest Tools: Technical Note

Background:

During the surgery for intrinsic brain lesions, it is important to plan the proper site of the craniotomy and to identify the relations with the gyri and superficial veins. This might be a challenge, especially in small subcortical lesions and when there is a distortion of the cortical anatomy.

Materials and Methods:

Using the free computer software Osirix, we have created a 3-dimensional reconstruction of the head and cerebral showing the gyri and superficial veins. With the aid of some tools, it is possible to create a colored image of the lesion and also to calculate the distance between the areas of interest and some easily identifiable structure, making it easier to plan the site of the craniotomy identify the topography of the lesion.

Results:

The reconstructions were compared to the intraoperative view. We found this technique to be useful to help identify the gyri and cortical veins and use them to find the lesions. The use of a region of interest to show better the lesion under the cortical surface and in the three-dimensional reconstruction of the head was also helpful.

Conclusions:

This is a low-cost and easy technique that can be quickly learned and performed before every surgery. It helps the surgeon to plan a safe craniotomy and lesionectomy.

Co-polysomy of 1p/19q in glial tumors: Retrospective analysis of 221 cases from single center

Glial tumors are malignant brain tumors that arise from glial cells of brain or spine and have genetic aberrations in their genome. 1p/19q co-deletion is associated with increased Overall Survival (OS) time with enhanced response to chemo- and radio-therapy in oligodendrogliomas. However, prognostic significance of 1p/19q co-polysomy is still unclear. We evaluated 1p/19q status of 221 patients with glial tumor by Fluorescent in situ Hybridization (FISH). Records of the patients were collected retrospectively. Our results demonstrated that 1p/19q co-polysomy was associated with decreased OS time, high P53 expression and frequently located in temporal lobe, whereas 1p/19q co-deletion was associated with increased overall survival time, low P53 expression and frontal lobe location. Furthermore, classification of patients based on both 1p/19q status and P53 expression revealed that patients with 1p/19q co-polysomy and high P53 expression had the worst prognosis. Lastly, our bioinformatic survival analysis revealed that high expression of SRM, ICMT, and FTL located in 1p36.13-p36.31 and 19q13.2-q13.33 region were related with decreased OS time in patients with Low Grade Glioma (LGG). The study demonstrated that 1p/19q co-polysomy is a poor prognostic marker for glial tumor.

The Evaluation of Proteoglycan Levels and the Possible Role of ACAN Gene (c.6423T>C) Variant in Patients with Lumbar Disc Degeneration Disease

BACKGROUND/AIM

The present study aimed to investigate the role of an aggrecan (ACAN) gene variant and proteoglycan levels in the risk of lumbar degenerative disc disease (LDDD).

MATERIALS AND METHODS

A total of 108 patients with LDDD and 103 healthy controls were enrolled. Molecular assessment of the ACAN gene (c.6423T>C) variant was determined by real time-polymerase chain reaction. Proteoglycan levels in serum were measured with enzyme-linked immunosorbent assay.

RESULTS

The frequency of all alleles and genotypes in all study groups were distributed according to the Hardy-Weinberg equilibrium. In addition, no association between the ACAN gene (c.6423T>C) variant and presence of risk factors for LDDD was detected. However, proteoglycan levels were significantly lower in patients with LDDD compared to the control group (p<0.00001).

CONCLUSION

Our findings suggest that proteoglycan has emerged as a potential novel biomarker which might be used for prediction of LDDD risk.

The Evaluation of Glutathione Reductase and Malondialdehyde Levels in Patients With Lumbar Disc Degeneration Disease

BACKGROUND/AIM

Increased oxidative stress plays a crucial role in pathogenesis of various diseases. The present study aims to investigate glutathione reductase (GR) and malondialdehyde (MDA) enzymes as markers of oxidative stress mechanisms in lumbar disc degeneration disease (LDDD).

PATIENTS AND METHODS

The study group consisted of 39 patients diagnosed with LDD and 37 healthy individuals in the control group. The enzyme-linked immunosorbent assay (ELISA) method was used to determine serum GR and MDA levels in the two study groups.

RESULTS

Serum GR levels were significantly lower (p=0.008), while MDA levels were significantly higher in the patient group compared to the controls (p=0.025).

CONCLUSION

Oxidative stress mechanisms play a crucial role in disc degeneration and GR deficiency could be an eligible risk factor for LDDD.

Association of rs2228570 Polymorphism of Vitamin D Receptor Gene with Lumbar Degenerative Disc Disease

AIM

To investigate the association between the vitamin D receptor (VDR) gene rs2228570 FokI polymorphism and the development of lumbar degenerative disc disease (LDDD) in the Turkish population.

MATERIAL AND METHODS

This was a prospective case-control study that included 45 patients with LDDD and 49 healthy individuals (control group). The clinical investigations of the LDDD patients consisted of neurological examinations, lumbar magnetic resonance imaging studies, visual analog scale (VAS) scores, and Oswestry Disability Index scores. The VDR gene rs2228570 FokI polymorphism was analyzed via a real-time polymerase chain reaction.

RESULTS

Individuals with the VDR GG genotype had a significantly increased risk of LDDD, while those with the AG genotype had a significantly decreased risk. In addition, the A allele may have a protective effect against LDDD in the Turkish population. Moreover, the VAS pain results showed that the GG genotype had a significantly higher score than the others.

CONCLUSION

VDR rs2228570 AG genotype is at a decreased risk and the GG genotype is at an increased risk of LDDD in the Turkish population. Since genetic polymorphisms often show ethnic differences, further functional studies are needed to evaluate the genotype and phenotype correlations in large cohorts of various ethnicities.

Simultaneous miRNA and mRNA transcriptome profiling of glioblastoma samples reveals a novel set of OncomiR candidates and their target genes

Although glioblastomas are common, there remains a need to elucidate the underlying mechanisms behind their initiation and progression and identify molecular pathways for improving treatment. In this study, sixteen fresh-frozen glioblastoma samples and seven samples of healthy brain tissues were analyzed with miRNA and whole transcriptome microarray chips. Candidate miRNAs and mRNAs were selected to validate expression in fifty patient samples in total with the criteria of abundance, relevance and prediction scores. miRNA and target mRNA relationships were assessed by inhibiting selected miRNAs in glioblastoma cells. Functional tests have been conducted in order to see the effects of miRNAs on invasion, migration and apoptosis of GBM cells. Analyses were carried out to determine correlations between selected molecules and clinicopathological features. 1332 genes and 319 miRNAs were found to be dysregulated by the microarrays. The results were combined and analyzed with Transcriptome Analysis Console 3 software and the DAVID online database. Primary differential pathways included Ras, HIF-1, MAPK signaling and cell adhesion. OncomiR candidates 21-5p, 92b-3p, 182-5p and 339-5p for glioblastoma negatively correlated with notable mRNA targets both in tissues and in in vitro experiments. miR-21-5p and miR-339-5p significantly affected migration, invasion and apoptosis of GBM cells in vitro. Significant correlations with overall survival, tumor volume, recurrence and age at diagnosis were discovered. In this article we present valuable integrated microarray analysis of glioblastoma samples regarding miRNA and gene-expression levels. Notable biomarkers and miRNA-mRNA interactions have been identified, some of which correlated with clinicopathological features in our cohort.

Tumor Necrosis Factor-Alpha (TNF-α-308 G>A) Polymorphism in High-grade Gliomas

BACKGROUND/AIM

High-grade gliomas (HGG) consist of anaplastic oligoastrocytomas, anaplastic oligodendrogliomas, anaplastic astrocytomas and glioblastoma multiforme. The present study aimed to evaluate TNF-α -308 G>A polymorphism in a Turkish population.

PATIENTS AND METHODS

This was a prospective case-control study that included 45 patients with HGG and 49 healthy individuals. All patients were operated for intracranial tumors and the pathology results consist of high grade (Grade3 and 4) glial tumors.

RESULTS

No significant differences were found between the HGG and control groups in terms of the median age (p=0.898). There were no significant differences with regard to gender (p=0.577). The TNF genotype frequency comparison between patients and controls was not statistically significant (p=0.598).

CONCLUSION

TNF genotype frequency comparison between the patients and controls was not statistically significant in the Turkish population tested. However, further studies are needed to evaluate the genotype and phenotype correlations in large cohorts of various ethnicities.

Leukemia Inhibitory Factor Promotes Aggressiveness of Chordoma

Chordomas are rare tumors of the spine and skull base that are locally destructive and resistant to chemotherapy and radiation therapy, with a poor prognosis and limited therapeutic options. Chordoma patients have a long life expectancy with high mortality from the disease. Cancer stem cells, which are known to exist in chordomas, have extensive proliferative and self-renewal potential and are responsible for maintaining tumor heterogeneity along with chemotherapy and radiotherapy resistance. Leukemia inhibitory factor (LIF) has multiple functions in stem cell biology, the immune response, and cancer, and is potentially a key molecule that allows cancer stem cells to self-renew. The purpose of this study was to determine whether LIF increases the aggressive traits of chordoma cells and leads to a poor prognosis in patients. Chordoma cell lines were treated with LIF, and functional tests were done. Twenty skull base chordoma samples were checked for levels of LIF and a correlation with clinicopathological features. The whole transcriptome microarray was used to observe changes in gene expression. We observed increased migration, invasion, tumorosphere formation, colony formation, epithelial–mesenchymal transition, and chemoresistance accompanied by a dramatic elevation in inflammatory gene networks and pathways in chordomas. The expression of LIF was associated with tumor size and a poorer overall survival. Microarray and quantitative real-time polymerase chain reaction assessments suggest that LIF can facilitate tumor-promoting inflammation. Results indicate that LIF plays a role in maintaining cancer stem cells in chordomas.