The Role of Hsp27 in Chemotherapy Resistance

Heat shock protein (Hsp)-27 is a small-sized, ATP-independent, chaperone molecule that is overexpressed under conditions of cellular stress such as oxidative stress and heat shock, and protects proteins from unfolding, thus facilitating proteostasis and cellular survival. Despite its protective role in normal cell physiology, Hsp27 overexpression in various cancer cell lines is implicated in tumor initiation, progression, and metastasis through various mechanisms, including modulation of the SWH pathway, inhibition of apoptosis, promotion of EMT, adaptation of CSCs in the tumor microenvironment and induction of angiogenesis. Investigation of the role of Hsp27 in the resistance of various cancer cell types against doxorubicin, herceptin/trastuzumab, gemcitabine, 5-FU, temozolomide, and paclitaxel suggested that Hsp27 overexpression promotes cancer cell survival against the above-mentioned chemotherapeutic agents. Conversely, Hsp27 inhibition increased the efficacy of those chemotherapy drugs, both in vitro and in vivo. Although numerous signaling pathways and molecular mechanisms were implicated in that chemotherapy resistance, Hsp27 most commonly contributed to the upregulation of Akt/mTOR signaling cascade and inactivation of p53, thus inhibiting the chemotherapy-mediated induction of apoptosis. Blockage of Hsp27 could enhance the cytotoxic effect of well-established chemotherapeutic drugs, especially in difficult-to-treat cancer types, ultimately improving patients' outcomes.

Neutrophil to lymphocyte ratio in the prediction of coagulopathy in traumatic brain injury

Aim: Traumatic brain injury (TBI) is a public health issue of increasing incidence. Coagulopathy after TBI is a frequent event, associated with a poor prognosis, and biomarkers that could predict coagulopathy occurrence are needed. The neutrophil-to-lymphocyte ratio (NLR) is useful as a cost-effective biomarker to assess prognosis and the need for cranial computed tomography in patients with mild TBI. As no study has yet evaluated the association of NLR with coagulopathy, we investigated whether the NLR at presentation could predict coagulopathy occurrence after TBI. Materials & methods: A retrospective study was conducted of patients aged >18 years who attended the emergency department (ED) with TBI, over a 3-year period. We included all patients for whom the NLR at presentation was available, and who underwent a brain CT scan. Results: The study included 173 patients (mean age 57.4 ± 21.1 years) with TBI, the most frequent cause of which was a fall. According to the Glasgow Coma Scale, 37 patients had severe TBI, 19 moderate and 117 mild TBI and 40 patients (23.1%) developed coagulopathy. Their mean NLR was 7.5 ± 6.7. Using receiver operating characteristic curve analysis, a cut-off value of 4.2 for NLR had 87.5% sensitivity and 52.9% specificity for predicting coagulopathy occurrence. Conclusion: Coagulopathy occurs frequently after TBI. This study investigated the value of NLR as a biomarker to predict coagulopathy occurrence, and concluded that NLR might be a novel and inexpensive biomarker for decision making in the management of TBI. Combination of NLR with other low-cost biomarkers and the clinical findings might further increase accuracy in the prediction of coagulopathy.

Expression of orexin-A (hypocretin-A) in the hypothalamus after traumatic brain injury: A postmortem evaluation

Traumatic brain injury (TBI) is one of the leading causes of mortality and morbidity. The key component of TBI pathophysiology is traumatic axonal injury (TAI), commonly referred to as diffuse axonal injury (DAI). Coma is a serious complication which can occur following traumatic brain injury (TBI). Recently, studies have shown that the central orexinergic/ hypocretinergic system exhibit prominent arousal promoting actions. Therefore, the purpose of this study is to investigate by immunohistochemistry the expression of beta-amyloid precursor protein (β-APP) in white matter of parasagittal region, corpus callosum and brainstem and the expression of orexin-A (ORXA) in the hypothalamus after traumatic brain injury. RESULTS: DAI was found in 26 (53.06%) cases, assessed with β-APP immunohistochemical staining in parasagittal white matter, corpus callosum and brainstem. Orexin-A immunoreactivity in hypothalamus was completely absent in 5 (10.2%) of the cases; moderate reduction of ORXA was observed in 9 (18.4%) of the cases; and severe reduction was observed in 7 (14.3%) of the cases. A statistically significant correlation was found between β-APP immunostaining in white matter, corpus callosum and brainstem in relation to survival time (p < 0.002, p < 0.003 and p < 0.005 respectively). A statistically positive correlation was noted between ORX-A immunoreactivity in hypothalamus to survival time (p < 0.003). An inverse correlation was noted between the expression of β-APP in the regions of brain studied to the expression of ORX-A in the hypothalamus of the cases studied (p < 0.005). CONCLUSIONS: The present study demonstrated by immunohistochemistry that reduction of orexin-A neurons in the hypothalamus, involved in coma status and arousal, enhanced the immunoexpression of β-APP in parasagital white matter, corpus callosum and brainstem.

The Role of Curcumin in Cancer Treatment

Curcumin is a polyphenol extracted from the rhizomes of the turmeric plant, Curcuma longa which has anti-inflammatory, and anticancer properties. Chronic inflammation is associated with the development of cancer. Curcumin acts on the regulation of various immune modulators, including cytokines, cyclooxygenase-2 (COX-2), and reactive oxygen species (ROS), which partly explains its anticancer effects. It also takes part in the downregulation of growth factors, protein kinases, oncogenic molecules and various signaling pathways, such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), c-Jun N-terminal kinase (JNK) and signal transducer and activator of transcription 3 (STAT3) signaling. Clinical trials of curcumin have been completed or are ongoing for various types of cancer. This review presents the molecular mechanisms of curcumin in different types of cancer and the evidence from the most recent clinical trials.

Anaplastic gangliogliomas of the spinal cord: a scoping review of the literature

Gangliogliomas (GGs) are rare, usually low-grade tumors that account for 1-2% of all central nervous system (CNS) neoplasms. Spinal GGs are exceedingly rare (1% of all spinal tumors) and the presentation of anaplastic features in them is even rarer. According to the last World Health Organization (WHO) classification of CNS neoplasms, anaplastic GG (AGG) is classified as a malignant neoplasm (grade III). We performed a scoping review of the literature to elucidate the epidemiology, clinical features, histopathology, treatment, and outcome of primary spinal AGGs, which, to the best of our knowledge, is the first such review. Relevant studies were identified by a search of the MEDLINE and SCOPUS databases, using the following combination of search strings: (anaplastic ganglioglioma or malignant ganglioglioma or high grade ganglioglioma) AND (spine or spinal or spinal cord). We included studies related to primary or recurrent AGGs and malignant transformation of low-grade GGs. The search produced 15 eligible studies, plus two studies from the references, all of which were case reports of patients with spinal AGGs (17 studies with 22 patients). The mean age of the patients was 21.4 years and the sex ratio was 1:1, with male predominance. Motor impairment was the most common presentation, followed by sensory impairment, gait problems, urinary disturbances, and back pain. The thoracic spine was the most frequently involved area (14/22) followed by the cervical (6/22) and lumbar (5/22) spine. In terms of histology, the anaplastic features were usually predominant in the glial element, resembling high-grade astrocytomas, while the neuronal element was composed of the so-called dysplastic ganglion (neuronal) synaptophysin-positive cells, without mitotic figures. Complete surgical resection of the tumor without neurological compromise, plus adjuvant chemotherapy and radiotherapy, was the treatment protocol implemented in the two patients with the best outcome. Primary spinal AGG is an exceedingly rare entity, with only 22 cases being retrieved after an extensive literature search. They appear to affect children and young adults and tend to manifest aggressive behavior. Most studies report that only the glial component of AGGs presents high-grade malignant features, with low mitotic activity in the neuronal component. We therefore suggest that, pending novel targeted therapy, AGGs should be treated as high-grade gliomas, with an aggressive treatment protocol consisting of maximal safe resection and adjuvant chemotherapy and radiotherapy.

Spontaneous epidural hematoma of the cervical spine in two patients with sarcoidosis

Background:

Sarcoidosis is correlated with hematological abnormalities that can result in spontaneous spinal epidural hematomas (EDH). As there is significant risk for permanent neurologic sequelae due to acute cord compression, these lesions often warrant emergent surgical intervention.

Case Description:

Two females, 56 and 62 years of age, respectively, both with sarcoidosis on corticosteroids, presented with the spontaneous acute onset of cervical pain, and progressive myeloradiculopathy. Emergent MR scans revealed cervical EDHs with cord compression, respectively, from C5-T1, and C6-C7. Following emergent laminectomies in both cases, patients’ neurological deficits resolved.

Conclusion:

Two patients with sarcoidosis at increased risk for spontaneous hemorrhages, presented with cervical EDHs warranting emergent decompressive laminectomies.

Transcutaneous Vagus Nerve Stimulation (t-VNS) and epilepsy: A systematic review of the literature

INTRODUCTION

Transcutaneous auricular vagus nerve stimulation (t-VNS) has been proposed as an alternative method for the treatment of various neurological and psychiatric disorders. Contrary to the classic invasive vagus nerve stimulation (i-VNS), t-VNS does not require surgical intervention. The application of t-VNS for the treatment of epilepsy has been poorly studied. Hence, we performed a systematic review of the literature to elucidate efficacy, adverse effects and technical features of t-VNS in patients with epilepsy.

MATERIAL AND METHODS

We systematically searched MEDLINE and SCOPUS databases using the following keywords: [TRANSCUTANEOUS VAGUS NERVE STIMULATION OR TRANSCUTANEOUS VAGAL NERVE STIMULATION] AND [EPILEPSY OR SEIZURES]. We searched for observational studies in English concerning the application of t-VNS for the treatment of epilepsy in humans. The full-text version of relevant studies was obtained and reviewed. Technical parameters of the stimulation, percentage of seizure frequency reduction, QOLIE-31(Quality of Life In Epilepsy-31) and LSSS (Liverpool Seizure Severity Scale) questionnaires and adverse effects were recorded and analyzed.

RESULTS

A total of 10 studies with 350 patients were included. Both bilateral and unilateral placement of the electrode were applied. Stimulation frequency varied from 10-30Hz, while treatment intensity was usually adjusted according to patients' preferences and tolerance (around 1mA) and below the pain threshold. In the clinical trials included in our review, the mean seizure frequency reduction varied from 30 to 65%. Eight and four studies provided information about QOLIE-31 and LSSS questionnaires respectively. Three studies reported a statistically significant (p<0,05) improvement in patients' quality of life and two studies reported statistically significant (p<0,05) seizure severity reduction. The most common side effect was headache (8,9%), followed by skin irritation at the placement site (7,1%) and nasopharyngitis (5,1%). No serious or life-threatening side effects were reported.

CONCLUSION

Due to the heterogeneity of the included studies, no safe conclusions could be extracted concerning the efficacy of t-VNS. However, the results of this review suggest that patients with epilepsy could possibly benefit from the use of t-VNS. The present study also emphasizes the limitations of previous clinical trials concerning the applications of t-VNS in people with epilepsy and thus could be a guidance for the conduction of future trials.

Hydrocephalus in primary intradural spinal cord tumors: a systematic review of the literature in the pediatric population

Hydrocephalus in children with primary intradural spinal cord tumors is exceedingly rare. Herewith, we performed a systematic literature review to address epidemiology, suggested pathophysiological mechanisms, prognostic factors, and treatment of such cases. We performed a systematic review with the best available evidence on cases of pediatric primary intradural tumors of the spinal cord presented with hydrocephalus. The patients were subjected to quantitative analysis on a basis of epidemiological features (age, sex, tumor type and location, clinical presentation, survival, dissemination). The possible pathophysiological theories are discussed in detail. Forty-four studies with a total of 121 patients were included in the study. Astrocytomas were the most frequent tumor (64.5%) type, while most tumors were located in cervical (31.4%) or cervicothoracic region (25.6%). About half of the cases concerned children under 6 years of age. The block of subarachnoid CSF (cerebrospinal fluid) pathways from disseminated tumor cells and the neoplastic inflammation caused by tumor elements advocated to be the major pathogenetic mechanisms. Surgical excision of the tumor and hydrocephalus treatment is usually performed. Primary intradural spinal cord tumors should be considered in children with communicative hydrocephalus of unknown etiology. Onset of hydrocephalus after tumor removal is related to higher mortality.

Neutrophil to lymphocyte ratio as a predictive biomarker for computed tomography scan use in mild traumatic brain injury

Aim: Traumatic brain injury (TBI) is a serious health concern. We set out to investigate the role of neutrophil-to-lymphocytes ratio (NLR) at admission for predicting the need for computed tomography (CT) in mild-TBI. Materials & methods: A retrospective study of adult patients who presented with mild-TBI Results: One hundred and thirty patients met the inclusion criteria. Seventy-four patients had positive CT-findings. The mean NLR-levels at presentations were 5.6 ± 4.8. Patients with positive CT-findings had significant higher NLR-levels. Receiver operating characteristic curve analysis was conducted and the threshold of NLR-levels for detecting the cases with positive CT-findings was 2.5, with 78.1% sensitivity and 63% specificity Conclusion: To the best of our knowledge no previous study has assessed the value of NLR-levels for predicting the need for CT in mild-TBI.

The emerging role of intraoperative flow cytometry in intracranial tumor surgery

Intraoperative flow cytometry has been recently emerged as a novel and promising tool for intracranial tumor surgery. Herewith, we discuss the role of intraoperative flow cytometry for the identification of gliomas boundaries, which may permit maximal resection and better prognosis. We also discuss its role in assessing tumor's grade of malignancy, both in adults and children and the prognostic information that may provide. Finally, intraoperative immunophenotypic analysis opens new horizons for flow cytometry. By evaluating tumor's specific cluster differentiation markers a diagnosis, within minutes, of certain tumor type can be achieved and additional information for therapeutic guidance can be provided.

Diagnostic performance of diffusion and perfusion MRI in differentiating high from low-grade meningiomas: A systematic review and meta-analysis

OBJECTIVES

The purpose of the present meta-analysis and systematic review was to evaluate the currently published data on the potential role of perfusion (PWI) and diffusion (DWI) weighted imaging for the assessment of meningioma grade.

PATIENTS AND METHODS

A search of MEDLINE and relative reference lists was conducted to identify all the eligible studies assessing the diagnostic performance of DWI and PWI in grading meningiomas. Meta-Disc and Rev-Man were used for the statistical analysis. Methodological quality and risk of bias were assessed with the use of the updated Quality assessment of the diagnostic accuracy (QUADAS-2) tool. Pooled sensitivity, specificity and area under the summary receiver operating characteristic curve were calculated individually for DWI and PWI to demonstrate the diagnostic performance of each modality.

RESULTS

Fourteen studies with 1063 patients were included. The 8 studies evaluating DWI showed a pooled sensitivity of 80% (95% CI, 74%-86%) and a pooled specificity of 76% (95% CI, 72%-79%). As for the 6 remaining studies concerning PWI, the pooled sensitivity and specificity were found 80% (95% CI, 71%-88%) and 91% (95% CI, 87%-94%), respectively. The area under the SROC curve was 0.94 (95% CI) for PWI and 0.91 (95% CI) for DWI. The comparison of the two AUCs showed that neither technique was superior with regards to the diagnostic performance.

CONCLUSIONS

The current evidence proves that both techniques are efficient at differentiating high from low-grade meningiomas.