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Lü-sheng Si

Publications and source records attributed to Lü-sheng Si.

14 recordsLinked to original sources
PubMed2006

[Small interfering RNA-mediated MAPK p42 silencing induces apoptosis of HeLa cells].

OBJECTIVE: To observe the effect of small interfering RNA (siRNA)-induced MAPK p42 silencing on the survival of HeLa cells. METHODS: Two siRNAs targeting at the MAPK p42 gene and one random siRNA were synthesized respectively by Silencer siRNA Construction Kit and transfected into HeLa cells by Lipofectamin 2000. The expression of p42(MAPK) in the transfected HeLa cells was analyzed by Western blotting and immunohistochemistry, and the morphology of cells were observed with electron microscope. TUNEL assay and Annexin V/PI staining were employed for detecting the cell apoptosis. RESULTS: The expression of p42(MAPK) in the HeLa cells was remarkably suppressed after transfection with the two siRNAs, reduced by about 2.5 and 3.2 folds respectively in comparison with the negative control. Chromatin margination in the cell nuclei were observed in the transfected cells, and TUNEL assay and Annexin V/PI staining further confirmed the occurrence of cell apoptosis. CONCLUSION: In vitro MAPK p42 siRNA-1 and siRNA-2 transfection can specifically silence the gene expression and induce apoptosis of HeLa cells.

Apoptosis↗
PubMed2006

[Inhibition of the expression of p42MAPK in HeLa cell line by RNA interference].

OBJECTIVE: To screen for siRNAs that inhibit the expression of p42(MAPK) in HeLa cell line. METHODS: Three p42(MAPK) siRNAs and one random siRNA were synthesized using Silencer siRNA Construction Kit, and labeled with Cy-3 for measurement of transfection effect. SiRNAs were transfected into HeLa cells by Lipofectamin 2000. The expression of p42(MAPK) was analyzed by Western blot. The biological effect of siRNAs on HeLa cell growth was monitored by MTT and flow cytometry. RESULTS: Two siRNAs (siRNA-2 and siRNA-3) among three tested were identified to be able to downregulate the p42(MAPK) expression. A concurrent growth retardation of HeLa cell line was observed in comparison with the control. CONCLUSION: Inhibition of p42(MAPK) expression with siRNA technique can inhibit the proliferation of HeLa cells.

Cell Cycle↗
PubMed2005

[New strategy of cancer immunotherapy: irradiation or chemotherapeutics-induced lymphopenia combined with immune reconstitution and tumor vaccine].

OBJECTIVE: To test whether vaccination performed during irradiation or chemotherapeutics-induced lymphopenia-driven T cell proliferation could augment the antitumor immunity. METHODS: The study composed of two parts, investigating the anti-tumor efficacy of performing tumor vaccination during early immune reconstitution period following sublethal total body irradiation and cyclophosphamide (Cy)-induced lymphopenia, respectively. Mice were subsequently reconstituted with naïve splenocytes from syngeneic mice and were named RLM (Reconstituted lymphopenic mice). Immunization/vaccination (F10) and adoptive immunotherapy (D5-G6) were used to explore anti-tumor immune responses in vaccinated irradiation/RLM and vaccinated Cy/RLM, respectively. Both normal C57BL/6 mice and RLM were vaccinated with irradiated, weakly immunogenic F10 melanoma cells and subsequently challenged with F10 cells. In addition, to determine the role of CD4(+) and CD8(+) T cells in the protective anti-tumor immune response, irradiation/RLM were depleted of these subpopulations by administration of the appropriate mAb around challenge. In the second part, adoptive immunotherapy was used to evaluate the anti-tumor immune responses under chemotherapeutics-induced lymphopenic condition. Both normal mice and RLM (Cy-treated) were vaccinated with GM-CSF-modified D5 melanoma cells (D5-G6) and tumor vaccine draining lymph nodes (TVDLN) were harvested 9-10 days later. Effector T cells were generated in vitro from TVDLN cells and adoptively transferred to mice bearing 3-day pre-established pulmonary metastases (D5). Recipient mice were sacrificed 2 weeks later after tumor inoculation and pulmonary metastases were enumerated. RESULTS: Significantly greater protection was induced in vaccinated irradiation/RLM, compared to vaccinated normal mice (63.2% vs 16.7%). Protective immunity in RLM depended on CD8(+) T cells. Increase in the interval between reconstitution and vaccination significantly decrease the protection. Effector T cells generated from vaccinated Cy-treated RLM demonstrated significantly higher in vivo anti-tumor efficacy over those of vaccinated normal mice. CONCLUSION: This study suggests that vaccination of RLM could elicit augmented antitumor immunity compared to normal hosts, highlighting the potential clinical benefit of performing tumor vaccination during irradiation or chemotherapeutics-induced lymphopenia in cancer patients.

Animals↗
PubMed2005

[Humoral immune response and in vitro neutralizing antibody assay on co-delivery of protein HPV16L1 virus-like particle with HPV16L1 gene].

OBJECTIVE: To compare humoral immune response by co-inoculating mice with antigen HPV16L1 virus-like particle (VLP) and HPV16L1 recombinant plasmids and then observing the neutralizing antibody activity in vitro. METHODS: C57BL/6 mice were injected intramuscularly/subcutaneously with pcDNA-L1 plasmids plus HPV16L1 VLP. Serum IgG levels were detected by ELISA, antibody neutralizing protective activities were determined by hemagglutination inhibition and HPV16L1 VLP binding inhibition assay. RESULTS: Serum antibody titers and neutralizing antibody activities were increased in HPV16L1 plasmids plus HPV16L1 VLP proteins in co-immunized mice when compared with controls. CONCLUSION: Co-inoculation of the HPV16L1 VLP protein can enhance production of neutralizing antibody activities against aimed antigen, which should be a more promising strategy for effective HPV16 prophylactic vaccine development.

Animals↗
PubMed2005

[The in situ analysis of cytokine mRNA expression in immunological microenvironment about non-small cell lung cancer].

AIM: Using Non-small cell lung cancer (NSCLC) as subject, to explore the characteristics of immune response in immunological microenvironment at the tumor site and its effect on anti-tumor immunity. METHODS: Using in situ hybridization (ISH), the expressions of IL-2, INF-gamma, IL-12 (p40), IL-18, IL-4, IL-10, TGF-beta1, IL-1, IL-3, IL-8, GM-CSF, TNF-alpha and TGF-alpha mRNAs in lymphocytes and tumor cells from five fresh pleural effusion samples and 18 tumor tissue samples of NSCLC patients were detected by in situ hybridization with digoxin end-labeled oligonucleotide probe, using 5 tuberculous pleurisy patients as control. RESULTS: In pleural effusion and tumor tissue of NSCLC patients, the expression levels of IL-4, IL-10, TGF-alpha, and TGF-beta1 mRNAs were significantly higher than those of IL-2, IL-12, IL-18 and INF-gamma mRNAs. In contrast, the analysis of tuberculous pleural effusion samples revealed lower levels of above-mentioned cytokine mRNA. There was no significant difference among expression levels of these cytokine mRNAs. CONCLUSION: The expressions of type II cytokine mRNAs and immunosuppressive cytokine mRNAs in pleural effusion and tumor tissue of NSCLC patients occupied a dominant position, suggesting that the immunological microenvironment about tumor be in an immunosuppressive state. The present study has contributed to a better understanding the mechanisms of tumor escape and provides important experimental basis for working out the scheme for an effective immunomodulatory treatment of NSCLC patients.

Carcinoma, Non-Small-Cell Lung↗
PubMed2005

[Expression of IgVH and B7-1 in proteome of the human colorectal carcinoma cell lines].

OBJECTIVE: To conduct a proteomic analysis of human colorectal carcinoma cell lines LS174T and SW480 by two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). METHODS: The total proteins of human colorectal carcinoma cell lines LS174T and SW480 were separated with 2-DE using immobilized pH gradient strips and analyzed by MALDI-TOF-MS to obtain peptide mass fingerprints (PMFs). Proteins were identified by using Mascot software to search protein databases. RESULTS: Good resolution 2-DE maps were obtained. Some proteins including immunoglobulin heavy chain variable region (IgVH) and co-stimulatory molecule B7-1 were identified. IgVH and B7-1 were confirmed by electrospray ionization tandem spectrometry (ESI-MS/MS) and immunocytochemistry. CONCLUSION: There are IgVH and B7-1 expressions in human colorectal carcinoma cell lines LS174T and SW480. Results obtained will help to elucidate the mechanisms of tumor immune escape.

B7-1 Antigen↗
PubMed2005

[Poorly-immunogenic tumor is capable of inducing proliferation of CD4 (+) CD25 (+) regulatory T-lymphocytes in vitro].

OBJECTIVE: To investigate the distribution of regulatory T-lymphocytes in the splenocytes cocultured with syngeneic low-immunogenic tumor cells, as compared with that of highly-immunogenic tumor cells, to investigate the mechanism underlining tumor evasion. METHODS: Three different immunogenic tumor cells were cocultured with syngeneic splenocytes individually to mimic cancer immunity in vitro. The proliferation response of splenocytes was measured by thymidine incorporation. The distribution of TR cells, CD4(+) IFN-gamma (+) T cells and CD4(+) IL-10(+) T cells were analyzed by flow cytometry. The secretion of IFN-gamma and IL-10 in supernatants was measured by ELISA assay. RESULTS: The stimulation Index of splenocytes cocultured with syngeneic highly-immunogenic H22 or FBL3 was much higher than that of poorly immunogenic melanoma D5. In each group, stimulation Index of splenocytes cocultured with allogeneic tumor cells was higher than that of the corresponding tumor immunity model. In addition, compared with those of highly-immunogenic tumors, there were more TR, CD4(+)IL-10(+) and less CD4 (+)IFN-gamma(+) T cells in the splenocytes, and higher IL-10 and lower IFN-gamma levels in the supernatant of the splenocytes stimulated with low-immunogenic D5 cells. CONCLUSION: Poorly-immunogenic tumor cells can induce the proliferation of TR cells, which may play an important role in tumor evasion.

Animals↗
PubMed2005

[Mechanism of augmented anti-tumor immunity in reconstituted lymphopenic mice immunized with melanoma vaccine].

OBJECTIVE: To explore mechanisms of the augmented anti-tumor immunity observed in reconstituted lymphopenic mice (RLM) receiving melanoma vaccination. METHODS: The study is to investigate the anti-tumor immunity of tumor vaccination during early immune reconstitution period following irradiation and cyclophosphamide (CY)-induced lymphopenia. Lymphopenic mice were subsequently reconstituted with naive splenocytes from syngeneic mice and immunized with irradiated melanoma cells F10 (irradiation experiment) and GM-CSF-modified D5 melanoma cells (D5-G6) (CY experiment). Controls included normal C57BL/6 mice receiving the corresponding vaccination, un-immunized naive mice and RLM. 8 - 10 days after vaccination, tumor vaccine draining lymph nodes (TVDLN) were harvested and phenotyped by FACS analysis. T cells purified from TVDLN were stimulated with anti-CD3 and anti-TCRbeta and proliferation was assessed by [(3)H]-TdR incorporation and FACS assay was performed for CD69 expression. RESULTS: The augmented anti-tumor immunity correlated with a significant increase in the percentage of T cells with activation/memory phenotype in the TVDLN of vaccinated RLM, compared to that of the controls. There was also a significant increase in the density of DCs in TVDLNs. The activation threshold of T cells generated from vaccinated RLM was significantly decreased, resulting in markedly enhanced proliferating capability upon anti-CD3 stimulation. CONCLUSION: This study suggests that the augmented anti-tumor immunity observed in vaccinated RLM is due to down regulated activation threshold of T cells during lymphopenia-driven T cell proliferation, which may in turn facilitate the breaking down of immune tolerance to weak tumor antigens upon vaccination with tumor cell vaccines.

Animals↗
PubMed2003

[Establishment and characterization of a new squamous cell carcinoma cell line CS1213 from the human uterine cervix].

OBJECTIVE: To establish a human cervical carcinoma cell line. METHODS: A primary culture was initiated from malignant tissue collected by dissection of cervical biopsy specimens. Characterizing cells in culture which included morphological observation, biological and karyotypic analysis, experimental tumorigenesis and the expression of p53, bcl-2 and Ki67 genes was carried out. RESULTS: The new established cervical carcinoma cell line (CS1213) had been maintained in culture for over 170 generations. The cells which were nonadherent had a common, rounded appearance with a cell cycle time of 25-hour and a 19 colony formation rate in soft agar. Electron micrographs demonstrated abundant tonofilaments in the cytoplasm. The karyotype showed a hyperdiploid feature with a main chromosome stem number ranged from 80 to 88. The culture was not contaminated by mycoplasma and had a distinct lactic acid dehydrogenase isozyme pattern. High expression level of p53 (31.9%), bcl-2 (89.3%) and Ki67 (33.7%) proteins was detected by flow cytometry. The xenogeneic tumors were grown in nude mice with the histological structure of the original one. CONCLUSIONS: The novel CS1213 cells have the characteristics of human cervical squamous cells and could be used as an appropriate cellular model system for studying tumor invasion and metastasis.

Animals↗