[Effect of Itk down regulation on cytokines production in Jurkat cell].

OBJECTIVE: To study the effect of Itk down regulation on Jurkat cell proliferation and inflammatory cytokines production, and provide useful data for Itk as an attractive target for potential drugs. METHODS: Three shRNAs against different region of Itk were constructed and cotransfected with pEGFP-C1-hItk. The shRNA, which can knock down Itk, was selected and packed into lentivirus. After Jurkat cells were transfected with shRNA lentivirus, the change of Itk protein expression, cell proliferation and cytokines production was observed. RESULTS: Itk mRNA was reduced about 55% in Jurkat cells transfected with Itk-shRNA1, compared with that in control cells shRNAnon (P < 0.05). Knocking down Itk expression had a profound inhibitory effect on Jurkat cell proliferation. In addition, there was a substantial decrease in level of cytokines, such as IL-2, IL-5, IL-10 and IFN-gamma, produced by cell transfected with Itk-shRNA1. CONCLUSION: Knocking down Itk expression can inhibit Jurkat cell proliferation and inflammatory cytokines production.

Biological properties of carbon/carbon implant composites with unique manufacturing processes.

The goal was to manufacture carbon/carbon (C/C) composites through a unique procedure with improved biocompatibility and reduced debris release. C/C composites were prepared by chemical vapor deposition, and their biological properties were analyzed. With regard to mechanical properties, compressive strength/modulus was 219.1 MPa/9.72 GPa, flexural strength/modulus was 121.63 MPa/21.9 GPa, and interlaminar sheer was 15.13 GPa. Biocompatibility testing revealed: (1) the extract liquid from the C/C composites had no effect on cell proliferation; (2) the extract had no impact on micronucleus frequency as compared with the control groups (P > 0.05); (3) in vivo, there was mild tissue inflammation after implantation within the first 2 weeks, but there was no significant difference compared with the control group (P > 0.05); (4) the implants were well integrated into the host tissue, and debris was limited. The tested samples have excellent biocompatibilities and reduced release of debris. The demonstrated changes in manufacturing procedures are promising.

[Expression of stathmin mRNA and protein in laryngeal squamous cell carcinoma and its clinical implication].

OBJECTIVE: To investigate the expressions of stathmin gene and its coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between stathmin gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma. METHODS: Laryngeal carcinoma tissues (studying group) in the tumors center and laryngeal normal tissues (control group) parted from 1.0 cm of the safe borderline of the tumors were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semiquantitative method of reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression level of stathmin mRNA, and immunohistochemical staining (frozen section) was used to detect the expressions of stathmin protein, in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively. RESULTS: mRNA of stathmin gene was all positively expressed in laryngeal carcinoma tissues and in laryngeal normal tissues of 38 cases by RT-PCR. However, stathmin mRNA was obviously overexpressed in laryngeal carcinoma tissues than that in laryngeal normal tissues (t = 9.655, P < 0.05). Immunohistochemical staining showed stathmin protein was positively expressed in laryngeal carcinoma tissues of 26 cases (26/38, 68.4%), and mild-positively expressed in laryngeal normal tissues in 13 cases (13/38, 34.2%). There was significant difference between the expression rate of stathmin protein in laryngeal carcinoma tissues and in laryngeal normal tissues (chi2 = 8.901, P < 0.05). Meanwhile, the expression level of stathmin mRNA and the positive-expressed rate of stathmin protein in laryngeal carcinoma tissues of the advanced stage patients group (III stage and IV stage) were significantly higher than these in laryngeal carcinoma tissues of I and II stage patients group (t = 6.284, chi2 = 5.810, P < 0.05), and they were also significantly higher in laryngeal carcinoma tissues of the patients group with cervical lymph node metastasis than in laryngeal carcinoma tissues of the patients group without cervical lymph node metastasis (t = 9.350, chi2 = 6.923, P < 0.05). CONCLUSIONS: The expression levels of stathmin gene and protein were significantly higher in laryngeal squamous cell carcinoma than these in laryngeal normal tissues, the levels are also significantly higher in advanced stage patients group (III stage and IV stage) than in the early stage patients group (I and II), and they are also related to the cervical lymph node metastasis of carcinoma. Stathmin gene may play an important role in the pathogenesis and development of laryngeal carcinoma and may be related to its prognosis.