[Expression and clinical significance of plasma microRNA-125b level in patients with oral squamous cell carcinoma].

PURPOSE: To explore the expression and clinical significance of plasma microRNA-125b (miR-125b) in patients with oral squamous cell carcinoma (OSCC). METHODS: By Stem-loop RT real-time PCR based on the SYBR Green, we investigated the expression of plasma miR-125b in 85 OSCC patients and 46 healthy controls, then evaluated its diagnostic performance as OSCC biomarker. Data analysis was performed with SPSS 17.0 software package for one-way ANOVA and receiver operating characteristic (ROC) curve. RESULTS: Stem-loop RT-PCR could specifically amplify miR-125b in plasma. The expression of plasma miR-125b was significantly increased in patients with OSCC compared with healthy controls (P<0.05). ROC results showed that miR-125b could differentiate OSCC from healthy controls(AUC=0.966). As fold change 3.46 was chosen for optimal cutoff value, the diagnostic sensitivity and specificity was 89.4% and 93.5%, respectively. CONCLUSIONS: Due to the satisfactory diagnostic performance, plasma miR-125b can be used as a promising biomarker in OSCC.

DOG1, cyclin D1, CK7, CD117 and vimentin are useful immunohistochemical markers in distinguishing chromophobe renal cell carcinoma from clear cell renal cell carcinoma and renal oncocytoma.

The distinction between chromophobe renal cell carcinoma (ChRCC), clear cell renal cell carcinoma (CRCC) and renal oncocytoma may cause a diagnostic dilemma. The usefulness of DOG1, cyclin D1, CK7, CD117 and vimentin in the differential diagnosis of these renal epithelial tumors was investigated. DOG1 was positive in ChRCC (32 of 32, 100%) and in renal oncocytoma (21 of 21, 100%). In contrast, DOG1 was absent in all CRCC (0 of 30). Cyclin D1 was positive in renal oncocytomas (17 of 21, 81%) but negative in the ChRCC (0/23) and CRCC (0 of 30). CK7 was positive in ChRCC (30 of 32, 94%), but was negative in oncocytoma (only scattered single positive cells), and was only focal positive in two cases of CRCC. CD117 was expressed in 88% of ChRCC (28 of 32), 86% of renal oncocytoma (18 of 21), and was negative in all CRCC (0 of 30). Twenty-six of the 30 cases of CRCC were positive (87%) for vimentin with prominent membrane staining patterns. All 23 chromophobe carcinomas were negative for vimentin and 15 of 21 oncocytomas demonstrated focal vimentin positivity, but less than 10%. The above results demonstrate that: (1) DOG1 was very sensitive and specific marker for distinguish ChRCC from CRCC; (2) Cyclin D1 was a useful marker to discriminate between ChRCC and renal oncocytoma; (3) CK7 and CD117 were useful markers to distinguish ChRCC from renal oncocytoma and CRCC. (4) Vimentin was helpful for distinguishing clear cell RCC from chromophobe and oncocytoma (87% of clear cell RCC positive, negative in chromophobe, only focally positive in oncocytoma). (5) CK8/18, CK19, CD10, ß-catenin and E-cadherin could not be used to distinguish ChRCC from renal oncocytoma and CRCC.

Expression and function of myelin-associated proteins and their common receptor NgR on oligodendrocyte progenitor cells.

Nogo-A, oligodendrocyte myelin glycoprotein (OMgp) and myelin-associated glycoprotein (MAG) are known as myelin-associated proteins that inhibit axon growth by binding a common receptor, the Nogo66 receptor (NgR). In the CNS, Nogo-A, OMgp and MAG are predominantly expressed by oligodendrocytes. As our previous study revealed that oligodendrocyte progenitor cells (OPCs) did not inhibit neurite outgrowth, it is not clear whether these myelin-associated proteins are expressed in OPCs, and what functions they perform if they are expressed in OPCs. In the present study, with OPCs induced from neural precursor cells (NPCs) derived from rat embryonic spinal cord, and oligodendrocytes differentiated from OPCs, we have observed the expression patterns of Nogo-A, OMgp, MAG and NgR in NPCs, OPCs and oligodendrocytes by immunostaining and western blot assay. We found that Nogo-A could be detected in all tested cells; OMgp could be detected in OPCs and oligodendrocytes, but not in NPCs; MAG was only detected in oligodendrocytes; while NgR could be detected in NPCs and OPCs, but not in oligodendrocytes. These results indicated that the expression pattern of MAG and NgR in OPCs was totally different from that of oligodendrocytes, which might be one of the factors that led to the discrepancy between the two cells in promoting neurite outgrowth. By respectively blocking Nogo-A, OMgp and NgR expressed on OPCs with their corresponding antibodies, we further investigated their roles in the proliferation and differentiation of OPCs, as well as the possible signal pathways involved in. Our results showed that when OPCs were cultured under proliferation condition, blocking Nogo-A, OMgp or NgR did not affect the proliferation of OPCs, but could all significantly prolong their processes. And this effect on OPC processes might involve the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. When OPCs were cultured under differentiation condition (containing tri-iodothyronine, T3), blocking Nogo-A, OMgp or NgR could all inhibit the differentiation of OPCs, and this effect might involve the extracellular signal-regulated kinases1/2 (Erk1/2) signaling pathway. These results suggested that under proliferation environment, the functions of Nogo-A, OMgp and NgR expressed in OPCs might be to control the length of processes, thus maintaining the morphology of OPCs. While in differentiation environment, the functions of Nogo-A, OMgp and NgR expressed in OPCs turned to promote the differentiation of OPCs, thus facilitating the maturation of oligodendrocytes. And NgR, as the common receptor for Nogo-A and OMgp, might be the main molecule that mediated these functions in OPCs.

[Expression and clinical significance of serum interleukin-8 level in patients with oral squamous cell carcinoma].

PURPOSE: To explore the clinical significance of serum interleukin-8 (IL-8) level in patients with oral squamous cell carcinoma (OSCC). METHODS: Twenty-seven serum specimens pathologically confirmed as OSCC were tested,10 healthy serum specimens were used as control. The expression of serum IL-8 was measured by ELISA. Data was presented as mean ± standard error. Statistical analysis was performed by SPSS 13.0 software package and two-tailed independent sample t test was used to determine the difference between the two groups. RESULTS: The level of serum IL-8 in OSCC patients was significantly higher than that in the control (P < 0.01). The high expression of IL-8 correlated with clinical pathologic stage (P < 0.01) and lymph node metastasis (P < 0.05). CONCLUSIONS: The expression of serum IL-8 correlates significantly with the biological behavior of OSCC, and it can be used as a prognostic molecular marker for OSCC. Supported by the Third Session of Excellent Youth Foundation of Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine.

[Clinical research for alimentary control of certain foods to remission of recurrent oral ulcer].

OBJECTIVE: In order to observe the therapeutic efficacy of food control to recurrent oral ulcer (ROU), alimentary control of certain foods was employed to relieve outbreak of ROU. METHODS: The kits for food intolerant IgG of certain food were used to test the intolerant food of fifty patients with ROU. Observations and assessments for alimentary control were made after three months' treatment on these patients. RESULTS: The top three of intolerant foods were crab, egg and milk and the remission rate of ROU reached 74% after treatment. CONCLUSION: The result of food intolerant IgG testing has certain function to alimentary control therapy for remitting the outbreak of ROU.

Chondroitin sulfate proteoglycans regulate the growth, differentiation and migration of multipotent neural precursor cells through the integrin signaling pathway.

BACKGROUND: Neural precursor cells (NPCs) are defined by their ability to proliferate, self-renew, and retain the potential to differentiate into neurons and glia. Deciphering the factors that regulate their behaviors will greatly aid in their use as potential therapeutic agents or targets. Chondroitin sulfate proteoglycans (CSPGs) are prominent components of the extracellular matrix (ECM) in the central nervous system (CNS) and are assumed to play important roles in controlling neuronal differentiation and development. RESULTS: In the present study, we demonstrated that CSPGs were constitutively expressed on the NPCs isolated from the E16 rat embryonic brain. When chondroitinase ABC was used to abolish the function of endogenous CSPGs on NPCs, it induced a series of biological responses including the proliferation, differentiation and migration of NPCs, indicating that CSPGs may play a critical role in NPC development and differentiation. Finally, we provided evidence suggesting that integrin signaling pathway may be involved in the effects of CSPGs on NPCs. CONCLUSION: The present study investigating the influence and mechanisms of CSPGs on the differentiation and migration of NPCs should help us to understand the basic biology of NPCs during CNS development and provide new insights into developing new strategies for the treatment of the neurological disorders in the CNS.

Expression and regulation of versican in neural precursor cells and their lineages.

AIM: To have a better understanding of the expression and regulation of versican isoforms in neural precursor cells (NPC) and oligodendrogliogenesis. METHODS: By immunocytochemistry, RT-PCR, and real-time PCR, we examined the temporal expression of versican in NPC isolated from embryonic d 16 rats as well as in oligodendrocyte (OL) lineage cells induced to differentiate from NPC, which mimicked the oligodendrogliogenesis in vivo. RESULTS: We found that versican was constitutively expressed in NPC and their lineage cells, including neurons, astrocytes, and OL. In addition, 2 versican isoforms, V1/V0 and V2, were found to express at low levels in NPC, but at significantly higher levels in OL lineage cells. The peak expression of versican V2 was found at the oligodendrocyte precursor cell stage. Furthermore, the treatment of 2 pro-inflammatory cytokines, TNF-alpha and IFN-gamma, enhanced the transcription of versican V2 in NPC in a dose-dependent manner, but showed no effect on V1/V0 expression. CONCLUSION: Taken together, our results demonstrate that versican, particularly the inhibitory V2 isoform, is increasingly expressed in OL lineage cells induced to differentiate from NPC. An increase in versican V2 expression after cytokine stimulation implies the interplay between the injury-induced upregulation of inflammatory cytokines and chondroitin sulfate proteoglycan-mediated inhibition of axonal regeneration after central nervous system injury.

[Chondroitin sulfate proteoglycans in neural development and regeneration].

Chondroitin sulfate proteoglycans (CSPGs) are major components of extracellular matrix in the central nervous system (CNS) , and play important roles in the development and maintenance of CNS, as welt in pathogenesis or repair processes of neuronal damages. They mainly exert barrier function for neuronal migration and axonogenesis during development and inhibitory effects on plasticity and axon re-growth in the adult nerve system. Digestion of glycosaminoglycan (GAG) chains or suppression of their synthesis could promote axonal regeneration and functional recovery after CNS injuries. However, many questions about the mechanisms regulating their expression pattern and signal transductions mediating their effects on neurons remain to be investigated.

The Spectroscopic Study of E. coli Arginyl-tRNA Synthetase (ArgRS) and its Mutants.

The conformation of native enzyme ArgRS and its mutants ArgRS306KA, ArgRS306KR and ArgRS381KA was studied by absorbance spectrum, Difference spectrum with solvent perturbation, fluorescence spectrum and CD spectrum. The results showed that the chromophores of ArgRS306KR and ArgRS306KA had shifted to different micro environments in comparison to the native enzyme. Compared to the native enzyme, ArgRS306KA had and even bigger conformational change than ArgRS306KR, while the conformation difference between ArgRS381KA and ArgRS was not big enough to be perceivable in the spectrum. The analysis of CD spectrum showed the less the percentage of beta-turn in the ArgRS mutants, the lower the activity of the mutants. The conclusion can be drawn that the positive charge of Lys306 is very important to maintain the conformation of ArgRS, the change of conformation might be mainly responsible for the loss of enzyme of the mutants, while the substitution of Lys381 seems to cause no perceivable change of the enzyme conformation.