Malignant gliomas: early diagnosis and clinical aspects

Altered plasma metabolite levels can be detected years before a glioma diagnosis

Genetic and metabolic changes in tissue and blood are reported to occur several years before glioma diagnosis. Since gliomas are currently detected late, a liquid biopsy for early detection could affect the quality of life and prognosis of patients. Here, we present a nested case-control study of 550 prediagnostic glioma cases and 550 healthy controls from the Northern Sweden Health and Disease study (NSHDS) and the European Prospective Investigation into Cancer and Nutrition (EPIC) study. We identified 93 significantly altered metabolites related to glioma development up to 8 years before diagnosis. Out of these metabolites, a panel of 20 selected metabolites showed strong disease correlation and a consistent progression pattern toward diagnosis in both the NSHDS and EPIC cohorts, and they separated future cases from controls independently of biological sex. The blood metabolite panel also successfully separated both lower-grade glioma and glioblastoma cases from controls, up to 8 years before diagnosis in patients within the NSHDS cohort and up to 2 years before diagnosis in EPIC. Pathway enrichment analysis detected metabolites related to the TCA cycle, Warburg effect, gluconeogenesis, and cysteine, pyruvate, and tyrosine metabolism as the most affected.

Diagnostic Accuracy of Magnetic Resonance Spectroscopy in Predicting the Grade of Glioma Keeping Histopathology as the Gold Standard

Background

Gliomas are the most prevalent intrinsic tumors of the central nervous system and are categorized from grade I to grade IV. Magnetic resonance imaging (MRI) provides exact diagnosis, prognosis, and assessment of tumor response to current chemotherapy/immunotherapy and radiation therapy. With histopathology serving as the gold standard, we aimed to assess the diagnostic accuracy of magnetic resonance spectroscopy (MRS) in predicting glioma grade.

Methodology

This cross-sectional study was conducted in the Department of Radiology, KRL Hospital, Islamabad, from December 15, 2019, to September 30, 2021. After providing written consent, 80 patients with untreated gliomas were included in this study. The voxel of interest was identified using MRI brain conventional contrast-enhanced sequences to assess the grade of the gliomas and link it to the histology report. Following this identification, tissue metabolites were calculated using MRS.

Results

The patients’ age ranged from 13 to 80 years, with a mean age of 49.5 years. Male patients comprised 57.5% of the total study population, while female patients comprised 42.5%. Overall, 23.75% of patients had low-grade tumors, while 76.25% had high-grade tumors. Low-grade tumors had a choline (Cho)/creatine (Cr) metabolite ratio of 1.7421, whereas high-grade tumors had an average Cho/Cr metabolite ratio of 2.5575. N-acetyl aspartate (NAA)/Cr ratio was 1.6368 in low grade and 0.6734 in high-grade tumors. Sensitivity of 77% and specificity of 84.2% were noted, with 78.75% diagnostic accuracy for the Cho/Cr ratio.

Conclusions

Multivoxel MRS has been shown to reliably predict the grade of gliomas despite its non-invasive nature and lack of procedural challenges. When used together Cho/Cr and NAA/Cr ratios and histopathology can accurately determine tumor grade and can be used as a supplementary non-invasive technique.

Targeted Delivery of Dual Anticancer Drugs Based on Self-Assembled iRGD-Modified Soluble Drug-Polymer Pattern Conjugate Nanoparticles

A tumor-penetrating peptide, iRGD (a tumor-homing peptide, CRGDKGPDC), could enhance the penetration of drugs via the specific receptor-binding affinity to αvβ3 and NRP-1 that overexpressed on tumor vasculature and tumor cells. Considering the side effects of traditional chemotherapy, here, poly(ethylene glycol) (PEG, Mw = 7500)-based and iRGD-modified poly(ethylene glycol)-based nanoparticles were successfully prepared. iRGD, as a tumor-targeting and tumor-penetrating agent, was combined with PEG after the esterification reaction between PEG and diosgenin (DGN). After the efficient loading of 10-hydroxycamptothecin (HCPT), the iRGD-PEG-DGN/HCPT NPs of chemotherapy were established. The characteristics of iRGD-PEG-DGN/HCPT NPs were evaluated. This nano-delivery system possessed high drug loading efficiency (∼17.34 wt % HCPT), controlled release rate, good pH response, and iRGD active targeting and passive targeting with an appropriate size (∼140 nm). All these features forcefully indicated that the iRGD-modified drug delivery system could markedly ameliorate the tumor therapy efficacy compared to the nontargeted nanoparticles through enhancing the tumor accumulation and penetration.

Subtle neuropsychiatric symptoms of glioblastoma multiforme misdiagnosed as depression

Glioblastoma multiforme (GBM) is the most common of the aggressive primary brain tumours arising in adults and has a dire prognosis. Neuropsychiatric symptoms can vary significantly among afflicted persons; psychiatric disturbances may be the predominant presenting symptoms. Distinguishing between functional psychiatric disorders, particularly depression, from other subtle neuropsychiatric disturbances that may accompany GBM can be challenging. The authors present a clinical case and review of the literature in an attempt to highlight the special considerations that should be taken into account when evaluating patients who present with late-onset or atypical symptoms, refractory psychiatric symptoms, or subtle neurological disturbances signalling the need for diagnostic assessment, particularly neuroimaging, for the presence of a tumour. Early diagnosis is critical for improvement in quality of life.

Medical Cannabis Use in Glioma Patients Treated at a Comprehensive Cancer Center in Florida

Background: Glioma is a devastating primary tumor of the central nervous system with difficult-to-manage symptoms. Cannabis products have been postulated to potentially benefit glioma patients. Recent state legalization allowed investigators an opportunity to study glioma patients' adoption of medical marijuana (MM). Objective: Our goals were to: (1) determine the prevalence of marijuana use, both through physician recommendation and self-medication, and (2) evaluate its perceived risks and benefits in glioma patients. Design: Self-report data were collected and descriptive analyses were conducted. Setting/Subjects: Participants were adult, English-speaking patients undergoing treatment for primary non-recurrent malignant glioma in neuro-oncology clinics at an NCI-designated Comprehensive Cancer Center. Measurements: The survey on MM was adapted from previous research and included questions on knowledge and attitudes toward MM; use, frequency, type, and sourcing of MM; and reasons for use of MM and perceived symptom relief among users. Results: A total of 73 patients were surveyed. The majority of participants were aware that MM was legal in the state, and most reported learning of this through the media. Over 70% of participants reported having considered using MM, and a third reported using marijuana products after their diagnosis. Most received recommendations from friends/family rather than a medical provider, and only half of the users had obtained a physician's recommendation. Users generally reported benefits. Conclusions: With the increasing national conversation that accompanies legalization, glioma patients are pursuing marijuana for the treatment for their symptoms. More research and education is needed to bring health care providers into the conversation.

Image and motor behavior for monitoring tumor growth in C6 glioma model

The primary objective of this study is to monitor tumor growth by using image techniques and behavioral testing through general and specific motor activities (spontaneous movements and gait). Our sample includes male Wistar rats, 2 months old and weighing 250-300 g, that is categorized into three groups: control, sham, and experimental. The experimental group was anesthetized; the C6 cells with luciferase expression that were suspended in a culture medium were implanted into the right frontoparietal cortex of the rats. The sham group received implant only with culture medium without cells. Images and behavioral tests were evaluated at base time and at 7, 14, 21, and 28 days after induced tumor growth analysis. The tumor volume measured by magnetic resonance imaging (MRI) and quantitative bioluminescence imaging (BLI) signal showed a correlation coefficient of r = 0.96. The MRI showed that the mean tumor volume increased by approximately 10, 26, and 49 times according to a comparison of tumor volume on the seventh day with 14, 21, and 28 days, respectively. The quantification of the BLI signal was (4.12 ± 2.01) x 10(8), (8.33 ± 3.12) x 10(8), (28.43 ± 6.32) x 10(8), and (63.02 ± 10.53) x 10(8) photons/s at the seventh, fourteenth, twenty-first, and twenty-eighth day, respectively. After 14 days of tumor induction, both behavioral tests showed significant differences between tumor and sham or control groups. Our study showed a high correlation between MRI and BLI for tumor growth monitoring with complement aspects analysis in tumor volume. In addition, functional behavioral analysis displayed sensitivity to monitor tumor growth, as well as to detect early significant changes between groups, primarily in the tumor group. The results of gait analysis were more sensitive than general motor analysis.

Sleep disturbance of adults with a brain tumor and their family caregivers: a systematic review

The high incidence and psychophysiological morbidities of sleep disturbance in cancer have been increasingly recognized. Yet, more detailed understanding of sleep disturbance and options for management have been neglected areas in both clinical care and research. Brain tumor patients have been particularly overlooked. A systematic search of the literature from 1990 to 2015 was performed to review sleep disturbance in adults with primary or secondary brain tumor and their family caregivers. Fifty eligible studies were identified, of which 12 focused on sleep, 37 reported sleep items within a health-related quality of life measure and 1 reported caregivers' sleep. No sleep intervention has been developed or tested for brain tumor patients. Sleep disturbance and somnolence were frequently reported as the most severely rated symptoms within health-related quality of life across the disease course or treatments, along with fatigue. However, sleep-focused studies yielded inconsistent results in small samples of mostly benign brain tumors in long-term remission from total tumor resection. The research using standardized, multifaceted sleep assessments, particularly in patients with malignant brain tumor and caregivers who are undergoing treatment, is seriously lacking. A more systematic examination of sleep disturbance is warranted to inform the development of better symptom management programs in this population.

Comparison of postoperative nausea between benign and malignant brain tumor patients undergoing awake craniotomy: a retrospective analysis

BACKGROUND

Benign and malignant brain tumors have different histopathological characteristics, including different degrees of tissue infiltration and inflammatory response. The aim of this retrospective study was to compare the incidence of postoperative nausea between the two categories of brain tumors in patients undergoing awake craniotomy.

METHODS

After IRB approval, we retrospectively extracted data from perioperative records between January 2005 and December 2010. Patients were divided based on the postoperative histopathological diagnosis into two groups, benign and malignant. The incidence of nausea, rescue anti-emetics, pain scores and postoperative analgesic requirements were compared between the two groups up to 12 hours postoperatively. Intraoperative anti-emetic, anesthetic, and analgesic regimens were also assessed. Limitations of this study include the retrospective design, the arbitrary dichotomization of tumors as benign or malignant, and the inability to gather accurate data regarding vomiting from the medical record.

RESULTS

Data from 415 patients were available for analysis, with 115 patients in the benign group and 300 patients in the malignant tumor group. A higher postoperative mean pain score was found in the benign brain tumor group compared to the malignant brain tumor group (P < 0.05). However, there was no difference in the incidence of nausea between the two groups.

CONCLUSION

The different histopathological characteristics of brain tumors have no association with postoperative nausea in patients undergoing awake craniotomy. Patients with benign brain tumors experience more pain than patients with malignant brain tumors. This difference in postoperative pain may be due to the younger age of the patients in the benign group.

Cationic core-shell nanoparticles with carmustine contained within O⁶-benzylguanine shell for glioma therapy

The application of carmustine (BCNU) for glioma treatment is limited due to its poor selectivity for tumor and tumor resistance caused by O⁶-methylguanine-DNA-methyl transferase (MGMT). To improve the efficacy of BCNU, we constructed chitosan surface-modified poly (lactide-co-glycolides) nanoparticles (PLGA/CS NPs) for targeting glioma, loading BCNU along with O⁶-benzylguanine (BG), which could directly deplete MGMT. With core-shell structure, PLGA/CS NPs in the diameter around 177 nm showed positive zeta potential. In vitro plasma stability of BCNU in NPs was improved compared with free BCNU. The cellular uptake of NPs increased with surface modification of CS and decreasing particle size. The cytotoxicity of BCNU against glioblastoma cells was enhanced after being encapsulated into NPs; furthermore, with the co-encapsulation of BCNU and BG into NPs, BCNU + BG PLGA/CS NPs showed the strongest inhibiting ability. Compared to free drugs, PLGA/CS NPs could prolong circulation time and enhance accumulation in tumor and brain. Among all treatment groups, F98 glioma-bearing rats treated with BCNU + BG PLGA/CS NPs showed the longest survival time and the smallest tumor size. The studies suggested that the co-encapsulation of BCNU and BG into PLGA/CS NPs could remarkably enhance the efficacy of BCNU, accompanied with greater convenience for therapy.

Active endocytosis and microtubule remodeling restore compressed pyramidal neuron morphology in rat cerebral cortex

Previous studies have shown that compression alone reduced the thickness of rat cerebral cortex and apical dendritic lengths of pyramidal neurons without apparent cell death. Besides, decompression restored dendritic lengths at different degrees depending on duration of compression. To understand the mechanisms regulating dendritic shortening and lengthening upon compression and decompression, we applied transmission electron microscopy to examine microtubule and membrane structure of pyramidal neurons in rat sensorimotor cortex subjected to compression and decompression. Microtubule densities within apical dendritic trunks decreased significantly and arranged irregularly following compression for a period from 30 min to 24 h. In addition, apical dendritic trunks showed twisted contour. Two reasons are accounted for the decrease of microtubule density within this period. First, microtubule depolymerized and resulted in lower number of microtubules. Second, the twisted membrane widened the diameters of apical dendritic trunks, which also caused a decrease in microtubule density. Interestingly, these compression-induced changes were quickly reversed to control level following decompression, suggesting that these changes were accomplished passively. Furthermore, microtubule densities were restored to control level and the number of endocytotic vesicles significantly increased along the apical dendritic membrane in neurons subjected to 36 h or longer period of compression. However, decompression did not make significant changes on dendrites compressed for 36 h, for they had already shown straight appearance before decompression. These results suggest that active membrane endocytosis and microtubule remodeling occur in this adaptive stage to make the apical dendritic trunks regain their smooth contour and regular microtubule arrangement, similar to that of the normal control neurons.