Role of SOCS and VHL Proteins in Neuronal Differentiation and Development.

The basic helix-loop-helix factors play a central role in neuronal differentiation and nervous system development, which involve the Notch and signal transducer and activator of transcription (STAT)/small mother against decapentaplegic signaling pathways. Neural stem cells differentiate into three nervous system lineages, and the suppressor of cytokine signaling (SOCS) and von Hippel-Lindau (VHL) proteins are involved in this neuronal differentiation. The SOCS and VHL proteins both contain homologous structures comprising the BC-box motif. SOCSs recruit Elongin C, Elongin B, Cullin5(Cul5), and Rbx2, whereas VHL recruits Elongin C, Elongin B, Cul2, and Rbx1. SOCSs form SBC-Cul5/E3 complexes, and VHL forms a VBC-Cul2/E3 complex. These complexes degrade the target protein and suppress its downstream transduction pathway by acting as E3 ligases via the ubiquitin-proteasome system. The Janus kinase (JAK) is the main target protein of the E3 ligase SBC-Cul5, whereas hypoxia-inducible factor is the primary target protein of the E3 ligase VBC-Cul2; nonetheless, VBC-Cul2 also targets the JAK. SOCSs not only act on the ubiquitin-proteasome system but also act directly on JAKs to suppress the Janus kinase-signal transduction and activator of transcription (JAK-STAT) pathway. Both SOCS and VHL are expressed in the nervous system, predominantly in brain neurons in the embryonic stage. Both SOCS and VHL induce neuronal differentiation. SOCS is involved in differentiation into neurons, whereas VHL is involved in differentiation into neurons and oligodendrocytes; both proteins promote neurite outgrowth. It has also been suggested that the inactivation of these proteins may lead to the development of nervous system malignancies and that these proteins may function as tumor suppressors. The mechanism of action of SOCS and VHL involved in neuronal differentiation and nervous system development is thought to be mediated through the inhibition of downstream signaling pathways, JAK-STAT, and hypoxia-inducible factor-vascular endothelial growth factor pathways. In addition, because SOCS and VHL promote nerve regeneration, they are expected to be applied in neuronal regenerative medicine for traumatic brain injury and stroke.

SOCS7-Derived BC-Box Motif Peptide Mediated Cholinergic Differentiation of Human Adipose-Derived Mesenchymal Stem Cells.

Adipose-derived mesenchymal stem cells (ADMSCs) are a type of pluripotent somatic stem cells that differentiate into various cell types such as osteoblast, chondrocyte, and neuronal cells. ADMSCs as donor cells are used to produce regenerative medicines at hospitals and clinics. However, it has not been reported that ADMSCs were differentiated to a specific type of neuron with a peptide. Here, we report that ADMSCs differentiate to the cholinergic phenotype of neurons by the SOCS7-derived BC-box motif peptide. At operations for patients with neurological disorders, a small amount of subcutaneous fat was obtained. Two weeks later, adipose-derived mesenchymal stem cells (ADMSCs) were isolated and cultured for a further 1 to 2 weeks. Flow cytometry analysis for characterization of ADMSCs was performed with CD73, CD90, and CD105 as positive markers, and CD14, CD31, and CD56 as negative markers. The results showed that cultured cells were compatible with ADMSCs. Immunocytochemical studies showed naïve ADMSCs immunopositive for p75NTR, RET, nestin, keratin, neurofilament-M, and smooth muscle actin. ADMSCs were suggested to be pluripotent stem cells. A peptide corresponding to the amino-acid sequence of BC-box motif derived from SOCS7 protein was added to the medium at a concentration of 2 µM. Three days later, immunocytochemistry analysis, Western blot analysis, ubiquitination assay, and electrophysiological analysis with patch cramp were performed. Immunostaining revealed the expression of neurofilament H (NFH), choline acetyltransferase (ChAT), and tyrosine hydroxylase (TH). In addition, Western blot analysis showed an increase in the expression of NFH, ChAT, and TH, and the expression of ChAT was more distinct than TH. Immunoprecipitation with JAK2 showed an increase in the expression of ubiquitin. Electrophysiological analysis showed a large holding potential at the recorded cells through path electrodes. The BC-box motif peptide derived from SOCS7 promoted the cholinergic differentiation of ADMSCs. This novel method will contribute to research as well as regenerative medicine for cholinergic neuron diseases.

Precision spinal gene delivery-induced functional switch in nociceptive neurons reverses neuropathic pain.

Second-order spinal cord excitatory neurons play a key role in spinal processing and transmission of pain signals to the brain. Exogenously induced change in developmentally imprinted excitatory neurotransmitter phenotypes of these neurons to inhibitory has not yet been achieved. Here, we use a subpial dorsal horn-targeted delivery of AAV (adeno-associated virus) vector(s) encoding GABA (gamma-aminobutyric acid) synthesizing-releasing inhibitory machinery in mice with neuropathic pain. Treated animals showed a progressive and complete reversal of neuropathic pain (tactile and brush-evoked pain behavior) that persisted for a minimum of 2.5 months post-treatment. The mechanism of this treatment effect results from the switch of excitatory to preferential inhibitory neurotransmitter phenotype in dorsal horn nociceptive neurons and a resulting increase in inhibitory activity in regional spinal circuitry after peripheral nociceptive stimulation. No detectable side effects (e.g., sedation, motor weakness, loss of normal sensation) were seen between 2 and 13 months post-treatment in naive adult mice, pigs, and non-human primates. The use of this treatment approach may represent a potent and safe treatment modality in patients suffering from spinal cord or peripheral nerve injury-induced neuropathic pain.

The potential diagnostic significance of crypt differentiation in gastric dysplasia.

AIMS: This study investigated the relationship between the differentiation of tumour cells into crypts, which is determined by cell differentiation into Paneth and neuroendocrine cells, and tumour infiltration in gastric dysplasia. METHODS AND RESULTS: The lesions were endoscopically biopsied low-grade dysplasia (LGD), endoscopically resected high-grade dysplasia (HGD) or cancer with submucosal invasion. LGD (n = 32) displayed crypt differentiation across the entire width of the tumour in all cases. Crypt differentiation was identified as a characteristic of tumours with low biological malignancy. HGD (n = 40) included tumours with a mixture of areas with and without crypt differentiation (n = 25) and tumours with crypt differentiation throughout the entire width (n = 15). Of the cancers with submucosal invasion (n = 30), the morphological progression of the HGD area with crypt differentiation, the HGD area without crypt differentiation and invasive cancer without crypt differentiation was confirmed for 23 samples. In two lesions, invasive cancer without crypt differentiation developed from HGD without crypt differentiation throughout the tumour width. In five samples, well-differentiated tubular adenocarcinoma with crypt differentiation developed from HGD with crypt differentiation and invaded with lamina propria-like stroma. CONCLUSIONS: Loss of crypt differentiation could be an objective indicator of infiltration in the progression of HGD to invasive cancer. The invasive potential of dysplasia depends upon the presence or absence of crypt differentiation.

Efficacy of Supraclavicular Scalenotomy Followed by External Neurolysis without Rib Resection for Post-traumatic Neurogenic Thoracic Outlet Syndrome.

MINI: Most patients with neurogenic thoracic outlet syndrome (NTOS) have a history of trauma. Scar tissue formation within the scalene muscle and around the nerves after injury cause arm and hand symptoms. We report that supraclavicular scalenotomy followed by external neurolysis without rib resection is very effective as the surgical treatment.

Consecutive case series. Our aim was to evaluate the outcomes of patients who underwent supraclavicular scalenotomy followed by external neurolysis without rib resection for post-traumatic NTOS. Neurogenic thoracic outlet syndrome (NTOS) comprises over 95% of all TOS patients, and most patients with NTOS have a history of trauma before the onset of their symptoms. Patients treated with supraclavicular scalenotomy and neurolysis without rib resection from September 2014 to December 2019 were retrospectively reviewed by using the medical records and operative notes. Patient's characteristics, clinical symptoms before treatment, operative findings, and short- and long-term outcomes were assessed. To assess clinical outcomes at 2 months after surgery (short-term outcomes) and 12 months later (long-term outcomes), we used a 4-grade categorization (Excellent, Good, Fair, and Poor) of patients' subjective evaluations after surgery on the basis of modified Odom's criteria. Excellent and Good were defined as a successful outcome. Ninety-six supraclavicular scalenotomies without rib resection were performed on patients with post-traumatic NTOS. The most common intraoperative observation was the fibrous bands within the anterior scalene muscle in 86 cases (89.6%). The short-term outcome with patients' subjective evaluation in 96 operations at 2 months after surgery showed a 96.9% success rate (Excellent + Good). In 85 cases followed for more than 12 months after surgery, the success rate based on patients' subjective evaluation at the last clinic follow-up appointment as a long-term outcome was 74.1%. In post-traumatic NTOS, it has been reported the arm and hand symptoms are due to pressure on the brachial plexus, which can stem from the swollen muscle following injuries and later from tightness of the scarred muscle. Considering this mechanism and our results, we concluded that supraclavicular scalenotomy and external neurolysis without rib resection made sense, as they were very effective and adequate to improve symptoms of NTOS. Level of Evidence: 5.

BC-Box Motif in SOCS6 Induces Differentiation of Epidermal Stem Cells into GABAnergic Neurons.

The BC-box motif in suppressor of cytokine signaling 6 (SOCS6) promotes the neuronal differentiation of somatic stem cells, including epidermal stem cells. SOCS6 protein belongs to the group of SOCS proteins and inhibits cytokine signaling. Here we showed that epidermal stem cells were induced to differentiate into GABAnergic neurons by the intracellular delivery of a peptide composed of the amino-acid sequences encoded by the BC-box motif in SOCS6 protein. The BC-box motif (SLQYLCRFVI) in SOCS6 corresponded to the binding site of elongin BC. GABAnergic differentiation mediated by the BC-box motif in SOCS6 protein was caused by ubiquitination of JAK2 and inhibition of the JAK2-STAT3 pathway. Furthermore, GABAnergic neuron-like cells generated from epidermal stem cells were transplanted into the brain of a rodent ischemic model. Then, we demonstrated that these transplanted cells were GAD positive and that the cognitive function of the ischemic model rodents with the transplanted cells was improved. This study could contribute to not only elucidating the mechanism of GABAnergic neuronal differentiation but also to neuronal regenerative medicine utilizing GABAnergic neurons.

Role of VHL-JAK-STAT signaling pathway in central nervous system hemangioblastoma associated with von Hippel-Lindau disease.

INTRODUCTION: Central nervous system hemangioblastoma is a benign tumor associated with or without von Hippel-Lindau (VHL) disease which is an autosomal dominant hereditary disease that results from a germline mutation in the VHL gene. A main axis of signaling pathways in central nervous system hemangioblastoma is VHL-HIF signaling pathway. Here, we propose an alternative VHL-JAK-STAT signaling pathway in hemangioblastoma and discuss the role. METHODS: Using MACS method, Scl+ hemangioblast-like cells were isolated from multipotent nestin-expressing stem cells. Then, ubiquitination of JAK2 in those cells and immunoprecipitation between JAK2 and VHL were examined. Then, expressions of JAK2 and STAT3 in those cells and expressions of VHL-associated hemangioblastoma tissues were examined. In addition, the VHL genes of patients bearing hemangioblastoma were analyzed. RESULTS: JAK2 and STAT3 in Scl+ hemangioblast-like cells were ubiquitinated after VHL- expression vector was transferred to those cells. Expressions of JAK2 and STAT3 in those cells were well recognized before the transfer, but those disappeared after the transfer. Expressions of both JAK2 and STAT3 in hemangioblastoma tissues were well shown. The VHL gene analysis revealed that patients bearing hemangioblastoma carried missense mutations in 5, small deletions in 2, large deletions in 4, and nonsense mutation in 1 CONCLUSIONS: VHL-JAK-STAT signaling pathway might play an important role in proliferation, angiogenesis, and maintenance of stem-cell-nature in hemangioblastoma as an alternative signaling pathway to supplement VHL-HIF signaling pathway.

Predictors of the Response to an Epidural Blood Patch in Patients with Spinal Leakage of Cerebrospinal Fluid.

BACKGROUND AND PURPOSE: An epidural blood patch (EBP) is a highly effective therapy for spinal cerebrospinal fluid (CSF) leakage. However, the factors predicting the response to an EBP have not been fully elucidated. The aim of this study was to elucidate factors predicting the response to an EBP. METHODS: We retrospectively examined the relationship between the response to an EBP and clinical variables of 118 patients with spinal CSF leakage, such as patient age, sex, etiology, interval from the onset to EBP application, CSF opening pressure (OP), radioisotope (RI) cisternography findings, rate of RI remaining in the CSF space, computed tomography (CT) myelography findings, magnetic resonance imaging (MRI) findings, and subjective symptoms (headache, vertigo/dizziness, visual disturbance, nausea, numbness, nuchal pain, back pain/lumbago, fatigability, photophobia, and memory disturbance). The correlations between these variables and the responses to EBPs were analyzed statistically. RESULTS: A positive response to an EBP was significantly (p<0.05) correlated with the following variables: <1.5 years from the onset to EBP application, age <40 years, CSF OP <7 cm H2O, epidural CSF leakage in RI cisternography, epidural CSF collection in MRI, <20% RI remaining after 24 hours, orthostatic headache, nausea, nuchal pain, and photophobia. The other variables did not show significant correlations with the responses to EBPs. CONCLUSIONS: It might be prudent to take the following variables into account when applying an EBP to treat spinal CSF leakage: the interval from the onset to EBP application, age, CSF OP, epidural CSF leakage in RI, epidural CSF collection in MRI, rate of remaining RI, orthostatic headache, nuchal pain, photophobia, and nausea.

Human recombinant erythropoietin improves motor function in rats with spinal cord compression-induced cervical myelopathy.

OBJECTIVE: Erythropoietin (EPO) is a clinically available hematopoietic cytokine. EPO has shown beneficial effects in the context of spinal cord injury and other neurological conditions. The aim of this study was to evaluate the effect of EPO on a rat model of spinal cord compression-induced cervical myelopathy and to explore the possibility of its use as a pharmacological treatment. METHODS: To develop the compression-induced cervical myelopathy model, an expandable polymer was implanted under the C5-C6 laminae of rats. EPO administration was started 8 weeks after implantation of a polymer. Motor function of rotarod performance and grip strength was measured after surgery, and motor neurons were evaluated with H-E, NeuN and choline acetyltransferase staining. Apoptotic cell death was assessed with TUNEL and Caspase-3 staining. The 5HT, GAP-43 and synaptophysin were evaluated to investigate the protection and plasticity of axons. Amyloid beta precursor protein (APP) was assessed to evaluate axonal injury. To assess transfer of EPO into spinal cord tissue, the EPO levels in spinal cord tissue were measured with an ELISA for each group after subcutaneous injection of EPO. RESULTS: High-dose EPO maintained motor function in the compression groups. EPO significantly prevented the loss of motor neurons and significantly decreased neuronal apoptotic cells. Expression of 5HT and synaptophysin was significantly preserved in the EPO group. APP expression was partly reduced in the EPO group. The EPO levels in spinal cord tissue were significantly higher in the high-dose EPO group than other groups. CONCLUSION: EPO improved motor function in rats with compression-induced cervical myelopathy. EPO suppressed neuronal cell apoptosis, protected motor neurons, and induced axonal protection and plasticity. The neuroprotective effects were produced following transfer of EPO into the spinal cord tissue. These findings suggest that EPO has high potential as a treatment for degenerative cervical myelopathy.

[Benedikt Syndrome Associated with Neck Clipping of Ruptured Basilar-Superior Cerebellar Artery Aneurysm:A Case Report].

Benedikt syndrome is caused by a rare type of brain damage to the red nucleus and nearby locations. Clinically, it presents as ipsilateral oculomotor palsy and specific contralateral involuntary movement. These involuntary movements may affect activities of daily living(ADLs)in affected patients. We treated a case of Benedikt syndrome associated with neck clipping of a ruptured basilar-superior cerebellar artery aneurysm. A 66-year-old female patient was admitted to our department with headache. Initial computed tomography imaging and angiography showed subarachnoid hemorrhage and left basilar-superior cerebellar artery aneurysm. We performed neck clipping of the aneurysm. Immediately after the surgery, left oculomotor nerve palsy occurred. Right involuntary movement gradually developed from the fifth day after the surgery. Postoperative magnetic resonance imaging(MRI)showed an infarction around the left red nucleus. This specific involuntary movement significantly impaired the ADLs of the patient and persisted for two months. From three months after the surgery, it gradually improved. One and a half years after the surgery, the ADLs of the patient improved notably. It is important to preserve perforators in the treatment of distal basilar artery aneurysm. However, while ischemia of the red nucleus(e.g., due to perforator damage)may cause specific involuntary movements, they could recover spontaneously after a period of months.

Delayed C5 Palsy After Anterior Cervical Decompression Surgery: Preoperative Foraminal Stenosis and Postoperative Spinal Cord Shift Increase the Risk of Palsy.

OBJECTIVE: Postoperative C5 palsy is a well-known complication after cervical decompression with either a posterior or an anterior approach. Its cause has been discussed more regarding the posterior approach. The main hypothesis is that postoperative spinal cord shift causes root traction and palsy. However, the pathogenesis in anterior cases has not been fully described. Therefore, the purpose of this study was to clarify the risk factors for C5 palsy in the anterior approach through our C5 palsy cases. METHODS: A total of 149 surgical patients with an anterior cervical lesion were treated by a specific spinal surgeon under consistent same treatment strategy. Of these patients, 88 who satisfied the evaluation criteria were enrolled. Postoperative C5 palsy was defined as postoperative weakness of the deltoid with or without weakness of the biceps brachii. Risk factors of C5 palsy were extracted from clinical backgrounds, surgical approaches, and radiologic findings from patients with palsy. RESULTS: Four sides of 3 individuals (4.6%) who underwent multiple corpectomy developed C5 palsy. All paralyses became evident several days after the surgery and recovered. Older age, multiple corpectomy, postoperative spinal cord shift, and foraminal stenosis of C4-5 and C5-6 were statistically extracted as causative factor of C5 palsy. In the patients with palsy, distortion of the anterior nerve root as a result of a residual vertebral spur was observed with anterior spinal cord shift after anterior corpectomy. CONCLUSIONS: Multiple corpectomy for patients with longer anterior lesions and locally developed kyphosis is related to a larger postoperative cord shift, which can cause the occurrence of C5 palsy. Moreover, C4-5 or C5-6 foraminal stenosis can accelerate tethering of the C5 or C6 nerve root. Older patients undergoing multiple corpectomy are susceptible to these risks of palsy. Appropriate patient selection and sufficient additional foraminotomy should be considered for extensive anterior lesions and locally developed kyphosis to avoid postoperative C5 palsy.

Survival of syngeneic and allogeneic iPSC-derived neural precursors after spinal grafting in minipigs.

The use of autologous (or syngeneic) cells derived from induced pluripotent stem cells (iPSCs) holds great promise for future clinical use in a wide range of diseases and injuries. It is expected that cell replacement therapies using autologous cells would forego the need for immunosuppression, otherwise required in allogeneic transplantations. However, recent studies have shown the unexpected immune rejection of undifferentiated autologous mouse iPSCs after transplantation. Whether similar immunogenic properties are maintained in iPSC-derived lineage-committed cells (such as neural precursors) is relatively unknown. We demonstrate that syngeneic porcine iPSC-derived neural precursor cell (NPC) transplantation to the spinal cord in the absence of immunosuppression is associated with long-term survival and neuronal and glial differentiation. No tumor formation was noted. Similar cell engraftment and differentiation were shown in spinally injured transiently immunosuppressed swine leukocyte antigen (SLA)-mismatched allogeneic pigs. These data demonstrate that iPSC-NPCs can be grafted into syngeneic recipients in the absence of immunosuppression and that temporary immunosuppression is sufficient to induce long-term immune tolerance after NPC engraftment into spinally injured allogeneic recipients. Collectively, our results show that iPSC-NPCs represent an alternative source of transplantable NPCs for the treatment of a variety of disorders affecting the spinal cord, including trauma, ischemia, or amyotrophic lateral sclerosis.

Time-dependent, bidirectional, anti- and pro-spinal hyper-reflexia and muscle spasticity effect after chronic spinal glycine transporter 2 (GlyT2) oligonucleotide-induced downregulation.

The loss of local spinal glycine-ergic tone has been postulated as one of the mechanisms contributing to the development of spinal injury-induced spasticity. In our present study using a model of spinal transection-induced muscle spasticity, we characterize the effect of spinally-targeted GlyT2 downregulation once initiated at chronic stages after induction of spasticity in rats. In animals with identified hyper-reflexia, the anti-spasticity effect was studied after intrathecal treatment with: i) glycine, ii) GlyT2 inhibitor (ALX 1393), and iii) GlyT2 antisense oligonucleotide (GlyT2-ASO). Administration of glycine and GlyT2 inhibitor led to significant suppression of spasticity lasting for a minimum of 45-60 min. Treatment with GlyT2-ASO led to progressive suppression of muscle spasticity seen at 2-3 weeks after treatment. Over the subsequent 4-12 weeks, however, the gradual appearance of profound spinal hyper-reflexia was seen. This was presented as spontaneous or slight-tactile stimulus-evoked muscle oscillations in the hind limbs (but not in upper limbs) with individual hyper-reflexive episodes lasting between 3 and 5 min. Chronic hyper-reflexia induced by GlyT2-ASO treatment was effectively blocked by intrathecal glycine. Immunofluorescence staining and Q-PCR analysis of the lumbar spinal cord region showed a significant (>90%) decrease in GlyT2 mRNA and GlyT2 protein. These data demonstrate that spinal GlyT2 downregulation provides only a time-limited therapeutic benefit and that subsequent loss of glycine vesicular synthesis resulting from chronic GlyT2 downregulation near completely eliminates the tonic glycine-ergic activity and is functionally expressed as profound spinal hyper-reflexia. These characteristics also suggest that chronic spinal GlyT2 silencing may be associated with pro-nociceptive activity.

Granulocyte Colony-Stimulating Factor Improves Motor Function in Rats Developing Compression Myelopathy.

STUDY DESIGN: Basic animal research. OBJECTIVE: The effects of granulocyte colony-stimulating factor (G-CSF) were assessed in a rat chronic spinal cord compression model to explore the potential of G-CSF as a pharmacological treatment for cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: G-CSF is a hematopoietic cytokine used clinically to treat neutropenia. Recently, neuroprotective effects of G-CSF have been reported in spinal cord disorders. METHODS: To introduce the chronic cervical cord compression, thin polyurethane sheets were implanted under C5-C6 laminae of rats and gradually expanded by absorbing water. This model reproduces delayed compressive myelopathy of the cervical spine. In sham operations, the sheets were immediately removed. G-CSF (15 µg/kg) or normal saline (NS) was administered subcutaneously 5 days a week. Experimental groups were sham operation given NS; cord compression given NS; and cord compression given G-CSF. To assess motor functions, rotarod performance, and grip strength were measured. Twenty-six weeks after surgery, cervical spinal cords were examined histopathologically. In the prevention experiment, G-CSF or NS administration was started immediately after surgery. In the treatment experiment, their administration was started 8 weeks after surgery. In another experiment, in three groups in the prevention experiment, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling staining was performed to assess apoptotic cell death at 8 weeks after surgery. RESULTS: In the prevention experiment, administration of G-CSF preserved the motor functions and motor neurons throughout the 26 weeks, and significantly decreased the number of apoptotic cells at 8 weeks. In the treatment experiment, G-CSF administration from 8 weeks after surgery markedly restored the motor function temporarily to a level equal to the sham group. CONCLUSION: G-CSF prevents the decline in motor functions and preserves motor neurons in the rat chronic cord compression model. G-CSF also improves motor function in the progressive phase of compression myelopathy. LEVEL OF EVIDENCE: N/A.

Occipitocervical fusion with relief of odontoid invagination: atlantoaxial distraction method using cylindrical titanium cage for basilar invagination--case report.

A 65-year-old woman presented with basilar invagination manifesting as neck pain, dysesthesia around the lips, and truncal ataxia. The radiological findings demonstrated invagination of the odontoid process into the medulla oblongata and vertical atlantoaxial subluxation with C1 assimilation. The clivo-axial angle was 88° and the cervicomedullary angle was 115°, indicating severe basilar invagination. We planned occipitocervical fusion with atlantoaxial distraction using a cylindrical titanium cage. C2 pedicle screws were inserted, and the atlantoaxial joint was opened to translocate the odontoid process downward. A cylindrical titanium cage packed with local bone graft was inserted into the opened facet joint space. Occipital-C2 fusion was completed by fastening the occipital bone plates with pedicle screws using titanium rods. Postoperatively, the apex of the odontoid process descended by 7 mm, and the clivo-axial and cervicomedullary angles opened to 112° and 125°, respectively. Invagination of the odontoid process into the medulla oblongata was relieved. The preoperative symptoms improved, and she remained symptom-free without requiring anterior decompression over 2 years. Bone fusion of the atlantoaxial joints was completed with sustained facet distraction 12 months after the surgery, and adequate relief of the basilar invagination was maintained. The atlantoaxial distraction method using a cylindrical titanium cage can be a useful option in posterior fusion surgery for basilar invagination.

Isolation of multipotent nestin-expressing stem cells derived from the epidermis of elderly humans and TAT-VHL peptide-mediated neuronal differentiation of these cells.

A specialized population of cells residing in the hair follicle is quiescent but shows pluripotency for differentiating into epithelial-mesenchymal lineage cells. Therefore, such cells are hoped to be useful as implantable donor cells for regenerative therapy. Recently, it was reported that intracellular delivery of TAT-VHL peptide induces neuronal differentiation of skin-derived precursors. In the present study, we successfully isolated multipotent stem cells derived from the epidermis of elderly humans, characterized these cells as being capable of sphere formation and strong expression of nestin, fibronectin, and CD34 but not of keratin 15, and identified the niche of these cells as being the outer root sheath of the hair follicles. In addition, we showed that TAT-VHL peptide induced their neuronal differentiation in vitro, and confirmed by fluorescence immunohistochemistry the neuronal differentiation of such peptide-treated cells implanted into rodent brains. These multipotent nestin-expressing stem cells derived from human epidermis are easily accessible and should be useful as donor cells for neuronal regenerative cell therapy.

The VHL tumor suppressor protein regulates tumorigenicity of U87-derived glioma stem-like cells by inhibiting the JAK/STAT signaling pathway.

The signal transducer and activator of transcription 3 (STAT3) factor plays an important role in the tumorigenicity of cancer stem cells. The purpose of this study was to investigate the inhibitory mechanism of this pathway acting through the tumor suppressor von Hippel-Lindau (VHL) protein in glioma cancer stem cells. We isolated floating neurosphere-forming CD133+ cells as glioma stem-like cells (GSLCs) by the MACS method. Furthermore, we examined these cells for their growth rate, ability to form colonies and neurospheres in soft agar, capacity for implantation into SCID mice and expression of CD133, STAT3, JAK2, Elongin A, PTEN and VHL. Furthermore, we transferred the VHL gene, an inhibitor of STAT3, into GSLCs using an adenovirus vector and compared these transfectants with control vector-transfected GSLCs. GSLCs proved to be implantable and formed a tumor in the subcutaneous tissue of SCID mice, the histology of which was similar to that of human glioblastomas. In addition, GSLCs exhibited a high capacity for soft agar colony and neurosphere formation, nearly all of which were CD133 positive. The majority of GSLCs were immunopositive for STAT3, JAK2 and Elongin A, but immunonegative for PTEN and VHL. When the VHL gene was transferred to GSLCs and these cells were transplanted into SCID mice, they did not result in tumor formation. Their capacity for soft agar colony and neurosphere formation was significantly inhibited, although their proliferation was only moderately inhibited. Regarding the expression of various factors, that of CD133 was decreased in the VHL transfectants and those of STAT3, JAK2 and Elongin A were eliminated. However, the expression of PTEN and of VHL was upregulated. These findings suggest that VHL regulated the tumorigenicity and self-renewal ability of glioma cancer stem cells by inhibiting the JAK/STAT signaling pathway.

[A case of recurrent breast cancer that responded to bevacizumab].

We report a case of a 59-year-old woman who was forced to undergo mastectomy of the right breast (Rt Bt) plus axillary lymph node (Ax) dissection for right breast cancer at another hospital. The pathological diagnosis was invasive ductal carcinoma( scirrhou[s sci], pT2N2M0, Stage IIIA, estrogen recepto[r ER[]+], progesterone recepto[r PgR[]+], human epidermal growth factor receptor-2[HER2][2+]). Although no recurrence was observed after postoperative adjuvant chemotherapy and endocrine therapy, skin metastasis on the left back and pleuritis carcinomatosa were detected at our hospital 9 years and 6 months after the operation. Thereafter, bone metastasis, contralateral lymph node metastasis, and frequent occurrence of hepatic metastasis were sequentially detected. The patient was treated with chemotherapy (a total of 4 regimens) and endocrine therapy in addition to radiation therapy for lymph node metastasis over a period of approximately 2 years and 3 months; however, disease control was poor. Therefore, combined chemotherapy with paclitaxel and bevacizumab was initiated from February 2012. Soon after the initiation of combination therapy, the serum carcinoembryonic antigen (CEA) level gradually reduced and computed tomography (CT) revealed that the multiple-organ metastases had remarkably reduced in size. The response was classified as a clinical partial response (cPR). Although adverse events such as peripheral neuropathy, nose bleeding, and high blood pressure were observed, these were all of lesser that Grade 2 severity. The efficacy of chemotherapy was noted for 11 months.

Anti-metastatic effect of capecitabine on human colon cancer xenografts in nude mouse rectum.

Capecitabine (N4-pentyloxycarbonyl-5'-deoxy-5-fluorocytidine) is a new fluoropyrimidine carbamate, which is converted to 5-fluorouracil (5-FU) by 3 sequential steps of enzyme reactions. We investigated the possibility of using capecitabine to prevent metastasis with a metastasis model of gastrointestinal cancer developed by the intrarectal injection of green fluorescent protein (GFP)-expressing colon cancer HT-29 cells (HT-29-GFP) into nude mice. Lung and lymph node metastasis in the HT-29-GFP rectal xenograft was assessed through both observation of GFP fluorescence and quantification of metastasis by amplification of a cancer-related human DNA by TaqMan PCR. Furthermore, for each organ, we examined mRNA levels of cancer-specific thymidine phosphorylase (dThdPase), which is an essential enzyme for capecitabine activation, by the quantitative RT-PCR method. Capecitabine inhibited the HT-29-GFP xenograft growth by 60.8% and 43.8% in the subcutaneous and rectal xenograft models, respectively. Furthermore, it inhibited both lung and lymph node metastasis by 99.9%. dThdPase expression in the tumor cells of both the rectal xenograft and metastatic lung tumor cells was upregulated by 10.0- and 24.3-fold that in the HT-29-GFP cells in vitro, respectively. These results indicated that capecitabine might effectively inhibit or suppress metastasis via upregulation of dThdPase expression. Capecitabine administration might be highly expected to reduce metastasis and improve survival of patients with gastrointestinal cancers.

Thiazolidinedione, a peroxisome proliferator-activated receptor-gamma ligand, inhibits growth and metastasis of HT-29 human colon cancer cells through differentiation-promoting effects.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) ligands inhibit the growth of PPAR-gamma expressing cancer cells through terminal differentiation. However, there are few studies examining the effect of a PPAR-gamma ligand on metastatic potential of cancer cells in an animal model and the underlying molecular mechanisms. We have recently developed a rectal cancer xenograft animal model in which anti-tumor and anti-metastatic efficacy of agents can be evaluated. This study was designed to examine whether a representative PPAR-gamma ligand, thiazolidinedione (TZD), could inhibit growth and metastasis of PPAR-gamma positive HT-29 human colon cancer cells through the induction of terminal differentiation. TZD caused G1 arrest in association with a marked increase in p21Waf-1, Drg-1, and E-cadherin expression. In untreated cancer cells, fluorescence immunostaining demonstrated beta-catenin in the nucleus and/or cytoplasm; in TZD-treated cancer cells, beta-catenin localization shifted to the plasma membrane, in association with increased E-cadherin at this site and reduced tyrosine phosphorylation of beta-catenin. In addition, TZD completely inhibited lymph node and lung metastases in the xenograft animal model, and TZD inhibited growth of primary xenografts by 40%. These results suggest that TZD can function as a cytostatic anti-cancer agent to inhibit growth and metastasis of HT-29 colon cancer cells through differentiation-promoting effects. These effects involve not only modulation of the E-cadherin/beta-catenin system, but also up-regulation of Drg-1 gene expression.