A phase II study of concurrent involved-field radiotherapy and intrathecal chemotherapy for leptomeningeal metastasis from solid tumors.

BACKGROUND: The role of involved-field radiation therapy (IFRT) and intrathecal chemotherapy (IC) in leptomeningeal metastasis (LM) from solid tumors was gradually underestimated in the era of targeted therapy. This study was aimed to investigate the safety and effectiveness of concurrent IFRT and intrathecal methotrexate (MTX)/cytarabine (Ara-C) for LM, particularly for those who developed LM while receiving targeted therapy. MATERIALS AND METHODS: Enrolled patients were given induction IC first and then concurrent treatment, which consisted of IFRT (40 Gy total; 2 Gy/f) and IC (MTX 15 mg or Ara-C 50 mg, once per week). Primary endpoint was clinical response rate (RR). Secondary endpoints were safety and overall survival (OS). RESULTS: Fifty-three patients received induction intrathecal MTX (n = 27) or Ara-C (n = 26). Forty-two patients completed concurrent therapy. Total RR was 34% (18/53). The improvement rate of neurological symptoms and KPS scores were 72% (38/53) and 66% (35/53) respectively. Adverse events (AEs) rate was 28% (15/53). Eight patients (15%, 8/53) showed grade 3-4 AEs, including myelosuppression (n = 4) and radiculitis (n = 5). Median OS was 6.5 months (95% CI, 5.3-7.7 months). Median survival for 18 patients who had clinical response was 7.9 months (95% CI, 4.4-11.4 months), and 0.8 months (95% CI, 0.08-1.5 months) for 6 patients who had LM progression. The median survival in 22 patients who received prior targeted therapy was 6.3 months (95% CI, 4.5-8.1 months). CONCLUSION: Concurrent IFRT and intrathecal MTX or Ara-C was proved to be a feasible treatment option with an acceptable safety profile for LM from a common tumor entity.

Intrathecal pemetrexed combined with involved-field radiotherapy as a first-line intra-CSF therapy for leptomeningeal metastases from solid tumors: a phase I/II study.

PURPOSE: A phase I/II study of intrathecal pemetrexed (IP) combined with involved-field radiotherapy (IFRT) was performed to determine feasibility, safety, and antitumor activity for leptomeningeal metastases (LM) from solid tumors. METHODS: Participants first received induction IP administration, followed by concomitant radiotherapy within 3 days. The concomitant regimen consisted of IP (pemetrexed 10 mg, dexamethasone 5 mg, once per week, 4 times in 4 weeks) and IFRT (40 Gy in 20 fractions). Six participants were recruited to assess feasibility in phase I, and then 28 patients were recruited further. All patients were assessed to investigate safety, efficacy, and outcomes. RESULTS: Between April 2018 and December 2018, 34 patients (male: 15; female: 19; median age: 56 years) were enrolled, including non-small-cell lung cancer (21), small-cell lung cancer (5), breast cancer (4), and others (4). Thirty-two patients received concurrent therapy and 25 (74%) patients completed the treatment. Major adverse events (AEs) consisted of myelosuppression, the elevation of hepatic aminotransferases, and radiculitis. Total AEs rate was 53% (18/34), including 6 (18%) patients with grade 3 and 1 (3%) with grade 4 AEs. The response rate was 68% (23/34). The median overall survival was 5.5 (0.3-16.6) months. Median neurological progression-free survival (NPFS) was 3.5 (0.3-15.2) months. Six-month NPFS rate was 47%. One-year survival rate was 21.6%. CONCLUSION: IP at a 10 mg dose on a schedule of 1-2 times per week presented good efficacy and safety in CSF. The concomitant regimen is an efficacious therapeutic option for LM patients with solid tumors. TRIAL REGISTRATION: This study (IPLM) was registered at https://register.clinicaltrials.gov [ClinicalTrials.gov identifier: NCT03507244].

Inhibition of microRNA-155 Reduces Neuropathic Pain During Chemotherapeutic Bortezomib via Engagement of Neuroinflammation.

As a chemotherapeutic agent, bortezomib (BTZ) is used for the treatment of multiple myeloma with adverse effect of painful peripheral neuropathy. Our current study was to determine the inhibitory effects of blocking microRNA-155 (miR-155) signal on BTZ-induced neuropathic pain and the underlying mechanisms. We employed real time RT-PCR and western blot analysis to examine the miR-155 and expression of pro-inflammatory tumor necrosis factor-α receptor (TNFR1) in the dorsal horn of the spinal cord. Its downstream signals p38-MAPK and JNK and transient receptor potential ankyrin 1 (TRPA1) were also determined. Mechanical pain and cold sensitivity were assessed by behavioral test. In result, inhibition of miR-155 significantly attenuated mechanical allodynia and thermal hyperalgesia in BTZ rats, which was accompanied with decreasing expression of TNFR1, p38-MAPK, JNK, and TRPA1. In contrast, miRNA-155 mimics amplified TNFR1-TRPA1 pathway and augmented mechanical pain and cold sensitivity. In addition, mechanical and thermal hypersensitivity induced by miRNA-155 mimics were attenuated after blocking TNFR1, p38-MAPK, JNK, and TRPA1. Overall, we show the key role of miR-155 in modifying BTZ-induced neuropathic pain through TNFR1-TRPA1 pathway, suggesting that miR-155 is a potential target in preventing neuropathic pain development during intervention of BTZ.

Role of microRNA-155 in modifying neuroinflammation and γ-aminobutyric acid transporters in specific central regions after post-ischaemic seizures.

In the central nervous system, interleukin (IL)-1ß, IL-6 and tumour necrosis factor (TNF)-α have a regulatory role in pathophysiological processes of epilepsy. In addition, γ-aminobutyric acid (GABA) transporter type 1 and type 3 (GAT-1 and GAT-3) modulate the levels of extracellular GABA in involvement in the neuroinflammation on epileptogenesis. Thus, in the current report we examined the effects of inhibiting microRNA-155 (miR-155) on the levels of IL-1ß, IL-6 and TNF-α, and expression of GAT-1 and GAT-3 in the parietal cortex, hippocampus and amygdala of rats with nonconvulsive seizure (NCS) following cerebral ischaemia. Real time RT-PCR, ELISA and Western blot analysis were used to examine the miR-155, proinflammatory cytokines (PICs) and GAT-1/GAT-3 respectively. With induction of NCS, the levels of miR-155 were amplified in the parietal cortex, hippocampus and amygdala and this was accompanied with increases of IL-1ß, IL-6 and TNF-α. In those central areas, expression of GAT-1 and GAT-3 was upregulated; and GABA was reduced in rats following NCS. Intracerebroventricular infusion of miR-155 inhibitor attenuated the elevation of PICs, amplification of GAT-1 and GAT-3 and impairment of GABA. Furthermore, inhibition of miR-155 decreased the number of NCS events following cerebral ischaemia. Inhibition of miR-155 further improved post-ischaemia-evoked NCS by altering neuroinflammation-GABA signal pathways in the parietal cortex, hippocampus and amygdala. Results suggest the role of miR-155 in regulating post-ischaemic seizures via PICs-GABA mechanisms.

Neuroinflammation and central PI3K/Akt/mTOR signal pathway contribute to bone cancer pain.

BACKGROUND: Pain is one of the most common and distressing symptoms suffered by patients with progression of cancer; however, the mechanisms responsible for hyperalgesia are not well understood. Since the midbrain periaqueductal gray is an important component of the descending inhibitory pathway controlling on central pain transmission, in this study, we examined the role for pro-inflammatory cytokines of the periaqueductal gray in regulating mechanical and thermal hyperalgesia evoked by bone cancer via phosphatidylinositide 3-kinase (PI3K)-mammalian target of rapamycin (mTOR) signals. METHODS: Breast sarcocarcinoma Walker 256 cells were implanted into the tibia bone cavity of rats to induce mechanical and thermal hyperalgesia. Western blot analysis and ELISA were used to examine PI3K/protein kinase B (Akt)/mTOR and pro-inflammatory cytokine receptors and the levels of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α). RESULTS: Protein expression levels of p-PI3K/p-Akt/p-mTOR were amplified in the periaqueductal gray of bone cancer rats, and blocking PI3K-mTOR pathways in the periaqueductal gray attenuated hyperalgesia responses. In addition, IL-1ß, IL-6, and TNF-α were elevated in the periaqueductal gray of bone cancer rats, and expression of their respective receptors (namely, IL-1R, IL-6R, and tumor necrosis factor receptor (TNFR) subtype TNFR1) was upregulated. Inhibition of IL-1R, IL-6R, and TNFR1 alleviated mechanical and thermal hyperalgesia in bone cancer rats, accompanied with downregulated PI3K-mTOR. CONCLUSIONS: Our data suggest that upregulation of pro-inflammatory cytokine signal in the periaqueductal gray of cancer rats amplifies PI3K-mTOR signal in this brain region and alters the descending pathways in regulating pain transmission, and this thereby contributes to the development of bone cancer-induced pain.

Long noncoding RNA SNHG16 reduced ketamine-induced neurotoxicity in human embryonic stem cell-derived neurons.

BACKGROUND: Clinical evidence demonstrates that prolonged exposure to ketamine may cause irreversible injury to immature human brains. In this study, we utilized an in vitro model to examine the function of long noncoding RNA (lncRNA) SNHG16 in ketamine-induced neurotoxicity in human embryonic stem cell (hESC)-derived neurons. METHODS: HESCs were induced toward neuronsin vitro, and treated with ketamine, at various concentrations, for 48 h. Viability, apoptosis, caspase-3 activity and ROS activity were then examined among hESC-derived neurons. Ketamine-induced gene expression change of SNHG16 was assessed by qRT-PCR. SNHG16 was overexpressed in hESC-derived neurons, which were then treated with ketamine, followed by biochemical assays to assess the effects of SNHG16 upregulation on ketamine-induced neurotoxicity. Correlation between SNHG16 and NeuroD1 gene was assess by qRT-PCR. In SNHG16-upregulated hESC-derived neurons, they were double transfected with siRNA to knock down NeuroD1. The functions of NeuroD1 inhibition on SNHG16-associated neural protection on ketamine-induced neurotoxicity were further assessed. RESULTS: 48-h in vitro treatment of ketamine induced significant neurotoxicity, and downregulated SNHG16 among hESC-derived neurons. Conversely, SNHG16 upregulation reduced ketamine-induced neurotoxicity. NeuroD1 expression was downregulated by ketamine in hESC-derived neurons, and concomitantly upregulated by SNHG16 overexpression. SiRNA-mediated NeuroD1 inhibition reversed the protection of SNHG16 upregulation on ketamine-induced neurotoxicity. CONCLUSIONS: SNHG16 is an important epigenetic factor which may functionally modulate ketamine-induced neurotoxicity through NeuroD1.

Blocking Mammalian Target of Rapamycin (mTOR) Alleviates Neuropathic Pain Induced by Chemotherapeutic Bortezomib.

BACKGROUND/AIMS: Bortezomib (BTZ) is largely used as a chemotherapeutic agent for the treatment of cancer. However, one of the significant limiting complications of BTZ is painful peripheral neuropathy during BTZ therapy. Drugs preventing and/or treating the painful symptoms induced by BTZ are lacking since the underlying mechanisms leading to neuropathic pain remain largely unclear. The purposes of this study were to examine 1) the effects of blocking mammalian target of rapamycin (mTOR) on mechanical pain and cold hypersensitivity evoked by BTZ and 2) the underlying mechanisms responsible for the role of mTOR in regulating BTZ-induced neuropathic pain. METHODS: Behavioral test was performed to determine mechanical pain and cold sensitivity in a rat model. Western blot analysis and ELISA were used to examine expression of mTOR and phosphatidylinositide 3-kinase (p-PI3K) signals, and the levels of substance P and calcitonin gene-related peptide (CGRP). RESULTS: Systemic injection of BTZ significantly increased mechanical pain and cold sensitivity as compared with control animals (P< 0.05 vs. control rats). The expression of p-mTOR, mTOR-mediated phosphorylation of p70 ribosomal S6 protein kinase 1 (p-S6K1), 4E-binding protein 4 (p-4E-BP1) as well as p-PI3K was amplified in the dorsal horn of spinal cord of BTZ rats as compared with control rats. Blocking mTOR by intrathecal infusion of rapamycin attenuated mechanical pain and cold hypersensitivity. Blocking PI3K signal also attenuated activities of mTOR, which was accompanied with decreasing neuropathic pain. Inhibition of either mTOR or PI3K blunted enhancement of the spinal substance P and CGRP in BTZ rats. CONCLUSIONS: The data for the first time revealed specific signaling pathways leading to BTZ-induced peripheral neuropathic pain, including the activation of mTOR and PI3K. Inhibition of these signal pathways alleviates pain. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of peripheral painful neuropathy observed during chemotherapeutic application of BTZ.

Involvement of pro-inflammation signal pathway in inhibitory effects of rapamycin on oxaliplatin-induced neuropathic pain.

Background Oxaliplatin is a third-generation chemotherapeutic agent that is commonly used to treat metastatic digestive tumors; however, one of the main limiting complications of oxaliplatin is painful peripheral neuropathy. The purpose of this study was to examine the underlying mechanisms by which mammalian target of rapamycin (mTOR) and its signal are responsible for oxaliplatin-evoked neuropathic pain. Methods Neuropathic pain was induced by intraperitoneal injection of oxaliplatin in rats. ELISA and Western blot analysis were used to examine the levels of pro-inflammatory cytokines (including interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α) and the expression of mTOR signal pathway. Results Oxaliplatin increased mechanical and cold sensitivity as compared with control animals ( P < 0.05 vs. control rats). Oxaliplatin also amplified the expression of p-mTOR and mTOR-mediated phosphorylation of p70 ribosomal S6 protein kinase 1 and 4E-binding protein 1 in the lumbar dorsal root ganglion. Blocking mTOR using rapamycin attenuated peripheral painful neuropathy observed in oxaliplatin rats ( P < 0.05 vs. vehicle control). This inhibitory effect was accompanied with decreases of IL-1ß, IL-6, and TNF-α. In addition, inhibition of phosphatidylinositide 3-kinase (p-PI3K) attenuated the expression of p-mTOR and the levels of pro-inflammatory cytokines in oxaliplatin rats, and this further attenuated mechanical and cold hypersensitivity. Conclusions The data revealed specific signaling pathways leading to oxaliplatin-induced peripheral neuropathic pain, including the activation of PI3K-mTOR and pro-inflammatory cytokine signal. Inhibition of these pathways alleviates neuropathic pain. Targeting one or more of these molecular mediators may present new opportunities for treatment and management of neuropathic pain observed during chemotherapeutic application of oxaliplatin.

Leptomeningeal metastasis of pulmonary large-cell neuroendocrine carcinoma: A case report and review of the literature.

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a rare and malignant form of lung cancer with a poor prognosis for patients. The common sites of metastases are the liver, adrenal glands, bone and brain. LCNEC rarely metastasizes to the small intestine, ovaries, tonsils, mandible, vulva or spine. To the best of our knowledge, there have been no reports of leptomeningeal metastasis of LCNEC to date. The present case report describes an unusual case of leptomeningeal metastasis from pulmonary LCNEC alongside a review of the literature. Biopsies of pulmonary lesions and cervical lymph nodes confirmed the diagnosis of LCNEC in a 39-year-old male patient. At 2 months after chemotherapy, the patient began to experience hoarseness, epileptic seizures and blurred vision. Furthermore, the patient presented with radiating pain and numbness in his lower left limb. Imaging findings and cytological examination of cerebral spinal fluid supported the diagnosis of leptomeningeal metastasis. The patient's neurological symptoms were markedly alleviated following receipt of radiation and intrathecal chemotherapy. The patient survived for 4.9 months after diagnosis with leptomeningeal metastasis. To the best of our knowledge, the present case report is the first to describe leptomeningeal metastasis from pulmonary LCNEC confirmed by neuroimaging and cerebral spinal fluid cytology. It suggests that leptomeningeal metastasis does occur in this rare disease, and aggressive treatment may result in improved symptoms and possibly survival times.

MicroRNA-497 suppresses cell proliferation and induces apoptosis through targeting PBX3 in human multiple myeloma.

Aberrant expression of microRNA-497 (miRN-497) is implicated in development and progression of multiple types of cancers. However, the biological function and underlying mechanism of miR-497 in multiple myeloma (MM) remains unclear. Thus, we studied the potential biological roles of miR-497 in MM. The expression of miR-497 was examined in multiple myeloma and normal plasma cells by qRT-PCR. Biological functions of miR-497 were analyzed using cell proliferation, colony formation, cell cycle, apoptosis and luciferase assays in vitro, as well as via tumorigenicity in vivo analysis. Here, we observed reduced expression of miR-497 in MM plasma samples and cell lines. Ectopic expression of miR-497 dramatically suppressed cell proliferation and clonogenicity, as well as induced cell arrest at G0/G1 stage and apoptosis in vitro. Mechanistic investigation assays showed that Pre-B-cellleukemia transcription factor 3 (PBX3) was a novel and direct downstream target of miR-497. Interestingly, overexpression of PBX3 partially reverted the effect of miR-497 in MM cells. In xenograft model, overexpression of miR-497 inhibited tumorigenicity by repressing PBX3. These findings collectively suggested that miR-497 functioned as tumor suppressor in MM by directly targeting PBX3, supporting its utility as a novel and potential therapeutic agent for MM therapy.

'Hot cross bun' sign with leptomeningeal metastases of breast cancer: a case report and review of the literature.

BACKGROUND: The 'hot cross bun' (HCB) sign refers to a cruciform-shaped hyperintensity within the pons found on T2-weighted magnetic resonance imaging (MRI). It is commonly associated with atrophy of the pons, cerebellum, and putamen in multiple system atrophy (MSA). In this report, we describe a rare case of the HCB sign in an adult female patient with leptomeningeal metastases of breast cancer without any signs of brain atrophy. CASE PRESENTATION: The patient was a 58-year-old woman diagnosed with grade 2 ductal breast carcinoma, who had undergone a right mastectomy, followed by chemotherapy treatments and chest wall radiotherapy. The tumor had metastasized to the skin, and the patient presented with vomiting, drowsiness, and intermittent episodes of confusion, slurred speech, and involuntary movements. Immunohistochemical staining demonstrated a triple-negative status of the tumor. Axial T1-weighted MRI showed a linear enhancement in the cerebellar sulcus. A diagnosis of leptomeningeal metastases of breast cancer was confirmed by detection of tumor cells in the cerebrospinal fluid. Axial T2-weighted MRI indicated a cruciform hyperintensity in the pons without any atrophy of the pons, cerebellum, or putamen. CONCLUSION: The HCB sign can occur with leptomeningeal metastases of solid tumors, though the underlying mechanisms remain unknown.

Thinprep plus Papanicolaou stain method is more sensitive than cytospin-coupled Wright Giems stain method in cerebrospinal fluid cytology for diagnosis of leptomeningeal metastasis from solid tumors.

BACKGROUND: The present study was designed to determine whether the Thinprep plus Papanicolaou stain (Thinprep) method is more sensitive than the Cytospin-coupled Wright-Giemsa (WG) stain (Cytospin) method in diagnosis of leptomeningeal metastasis (LM) from malignant solid tumors in cerebrospinal fluid (CSF). We also explored if the Thinprep method could be used in the differential diagnosis of the type of primary tumor cells based on the morphology of tumor cells in CSF samples. METHODS: The morphological features of tumor cells in fresh CSF samples were analyzed using both methods. The tumor cell detection rates were compared between the two methods. RESULTS: Using the Thinprep method, we found that each type of tumor cells in the CSF samples had specific identifiable morphological features linked to their primary cancer origins, such as adenocarcinomas originated from the lungs, breast, and stomach, and lung squamous cell carcinomas, small cell lung cancer, large-cell neuroendocrine lung cancer, hepatocellular carcinoma, and malignant melanoma. In a retrospective study with 88 LM patients, cancer cells were detected in 80 out of the 88 CSF samples. In the comparative study with 45 LM patients, the initial detection rate of the Thinprep method was significantly higher than that of the Cytospin method (73.3% vs. 57.8%, P<0.01). The cell morphology was better preserved and subcellular structures were clearer using the Thinprep method, compared to the Cytospin method. CONCLUSIONS: The Thinprep method is more sensitive and suitable for LM diagnosis in CSF in patients with malignant solid tumors than the Cytospin method. The Thinprep method may facilitate primary tumor detection and help design early treatment regimens for LM patients with tumors of unknown primary origin.

Leptomeningeal metastasis from early glottic laryngeal cancer: A case report.

The present study reports the case of a 53-year-old man with leptomeningeal metastasis from early glottic laryngeal cancer. The patient had been diagnosed with squamous cell carcinoma of the glottic larynx 9 years previously. The current symptoms included a recurring headache that had persisted for 1 month and vomiting for 1 week. A magnetic resonance imaging scan of the head revealed multiple enhancing lesions in the brain and multiple line-like enhancements in the brain fold. Computed tomography scans of the head, neck, chest and abdomen showed no nodular lesions. Cytological examination of the cerebral spinal fluid (CSF) revealed malignant cells with a scattered distribution pattern. The patient received intra-CSF methotrexate chemotherapy concurrent with whole-brain radiotherapy, which relieved the neurological symptoms. To the best of our knowledge, this is the first case of cytologically-confirmed LM from early glottic laryngeal cancer.

Leptomeningeal metastasis from hepatocellular carcinoma with other unusual metastases: a case report.

BACKGROUND: Leptomeningeal metastasis, which results from metastasis of tumors to the arachnoid and pia mater, can lead to the dissemination of tumor cells throughout the subarachnoid space via the cerebral spinal fluid, and frequently with a poor prognosis. The primary tumor in adults is most often breast cancer, lung cancer, or melanoma. Although leptomeningeal metastasis due to cholangiocarcinoma has been reported, to the best of our knowledge there is no cytologically confirmed report of leptomeningeal metastasis from hepatocellular carcinoma. CASE PRESENTATION: We herein report a case of leptomeningeal metastasis from hepatocellular carcinoma in a 53-year-old woman with concomitant systemic metastases to the lung, bone, brain, kidney, adrenal gland, subcutaneous tissues, and abdominal pelvis. The neurological symptoms of the patient were relieved after treatment with methotrexate intra-cerebral spinal fluid chemotherapy concurrent with whole brain radiotherapy. CONCLUSION: To our knowledge this is the first report of leptomeningeal metastasis from hepatocellular carcinoma confirmed by cytology. Treatment with methotrexate intra-cerebral spinal fluid chemotherapy concurrent with whole brain radiotherapy was effective.