N-3 polyunsaturated fatty acids intake and risk of colorectal cancer: meta-analysis of prospective studies.

BACKGROUND: Growing body of laboratory evidence supports the beneficial effects of n-3 polyunsaturated fatty acids (PUFAs) on colorectal cancer (CRC) prevention. Epidemiologic studies investigating the relationship between n-3 PUFAs intake and risk of CRC, however, have been inconsistent. We aimed to clarify the relation by conducting a meta-analysis of prospective studies. METHODS: Eligible studies were identified by searching PubMed database and by carefully reviewing bibliographies of retrieved publications. Summary relative risks (RRs) with their 95 % confidence intervals (CIs) were computed with a random-effects model. Subgroup, meta-regression, and dose-response analyses were performed to explore potential sources of heterogeneity. RESULTS: A total of 14 prospective studies involving 8,775 cancer cases were included in the final analysis. Overall, total n-3 or marine PUFAs intake was not associated with risk of CRC (RR 0.99 and 1.00). However, there was a trend toward reduced risk of proximal colon cancer (total n-3 PUFAs: RR 0.83, 95 % CI 0.66-1.05; marine PUFAs: RR 0.81, 95 % CI 0.59-1.10) and a significant increased risk of distal colon cancer (total n-3 PUFAs: RR 1.26, 95 % CI 1.06-1.50; marine PUFAs: RR 1.38, 95 % CI 1.11-1.71). Furthermore, marine PUFAs intake accessed longer before diagnosis was associated 21 % reduced risk of CRC (RR 0.79, 95 % CI 0.63-1.00). CONCLUSION: Overall, this meta-analysis finds no relation between n-3 PUFAs intake and risk of CRC. The observed subsite heterogeneity within colon cancer and the possible effect modification by latency time merit further studies.

[Pollution Characteristics and Risk Assessment of Heavy Metals in Surface Dusts and Surrounding Green Land Soils from Yellow River Custom Tourist Line in Lanzhou].

In order to investigate the contamination levels of dust and its surrounding green land soil heavy metal pollution and potential ecological and health risks in the scenic areas of urban waterfront parks, the gardens, squares, and theme parks of the Yellow River Custom Tourist Line in Lanzhou were selected as the research area, using 27 dust samples and 26 soil samples from its surrounding green lands. The contamination characteristics and potential ecological risks of eight heavy metals (Cr, Ni, Cu, Zn, As, Cd, Hg, and Pb) were evaluated using the geo-accumulation index (Igeo), single-factor pollution index (Pi), Nemerow integrated pollution index (PN), and improved potential ecological risk index (RI). The human health risk assessment was also evaluated using the exposure risk model. The results showed that the average concentrations of the other heavy metals in the surface dusts were higher than the background values of Gansu Province and Lanzhou City, except that the As mean concentrations in the surface dusts and the surrounding green land soils were slightly lower than the Gansu Province background values. For its surrounding green land soils, the mean concentrations of the other heavy metals (Cu, Zn, Cd, Hg, and Pb) exceeded the soil background values of Gansu Province and Lanzhou City, whereas the Cr and Ni mean concentrations were lower than their corresponding soil background values of Gansu Province and Lanzhou City. The geo-accumulation and single-factor pollution indices demonstrated that a slight to moderate pollution of Cr, Cu, Zn, Cd, Hg, and Pb occurred in surface dusts, and Cu, Zn, Cd, Hg, and Pb appeared in varying degrees of contamination levels in its surrounding green land soils. The Nemerow integrated pollution index analysis manifested that the overall contamination status of the study areas was between slightly and heavily polluted. The potential ecological risk index suggested that Cd and Hg were recognized as significant pollutant elements and that the RI of the other heavy metals were all below 40, presenting slight ecological risk. The health risk assessment indicated that ingestion was the dominant exposure pathway for heavy metals from the surface dusts and the surrounding green land soils, and no carcinogenic and noncarcinogenic risks posed threats to adults and children.

[Multi-center phase II clinical trial of humanized anti-epidermal factor receptor monoclonal antibody h-R3 combined with radiotherapy for locoregionally advanced nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the efficacy and safty of the humanized anti-epidermal factor receptor monoclonal antibody h-R3 in combination with radiotherapy for locoregionally advanced nasopharyngeal carcinoma. METHODS: Totally, 137 patients from 7 medical center around China were randomly divided into combined therapy group or control group. There was no difference in Karnofsky performance score between two groups. All patients in both groups received radical conventionally fractionated radiotherapy to the total dose of D(T) 70-76 Gy. For the combined therapy group, h-R3 was added at a dose of 100 mg i.v. weekly for 8 weeks started at the beginning of radiotherapy. RESULTS: Of the 137 eligilbe patients, 70 were in the combined therapy group treated by h-R3 plus radiotherapy and 67 in the control group by radiotherapy alone. The intent-to-treat (ITT) population consisted of 130 patients, while the per-protocol (PP) population was composed of 126 patients. The efficacy was assessed respectively at three point of time: the end of treatment, the 5th- and 17th-week after treatment. The complete response (CR) of the combined therapy group was significantly higher than that of the control group in both ITT and PP (ITT: 65.63%, 87.50%, 90.63% versus 27.27%, 42.42%, 51.52%; PP: 67.21%, 90.16%, 93.44% versus 27.69%, 43.08%, 52.31%; P < 0.05, respectively). The most common h-R3-related adverse reactions were fever (4.3%), hypotension (2.9%), nausea (1.4%), dizziness (2.9%) and rash (1.4%), which could be reversible if treated properly. Radiotherapy combined with 100 mg h-R3 i. v. weekly was tolerable and did not aggravate the side effects of radiation. The quality of life in the combined therapy group was comparable to that in the control group. CONCLUSION: This phase 1 multicenter clinical trial shows that h-R3 in combination with radiotherapy is effective and well-tolerated for the treatment of locoregionally advanced nasopharyngeal carcinoma.

The detection of phytohemagglutinin-lymphokine activated killer cells' in vitro antitumor action with MTT colorimetry.

OBJECTIVE: To detect the in vitro antitumor action of phytohemagglutinin and lymphokine activated killer (PHA- LAK) cells. METHOD: MTT colorimetric assay was used to detect the in vitro cytotoxicity of PHA-LAK cells on K562 MGc80-3 143TK Hela and LoVo. RESULTS: The significant cytotoxicity of PHA-LAK cells on these five tumor cells from different organs could be found in vitro. The PHA-LAK cell activity on 143TK could reach 57.3% when the ratio of effective cell (EC) to target cell (TC) was 7.5:1. The antitumor effect did not increased or even decreased when the ratio of EC to TC was 15:1. CONCLUSIONS: (1)PHA-LAK cell has non-specific cytotoxicity against tumor cells and can overcome the problems of the quantity and activity of immunocyte of traditional adoptive cellular immunotherapy. (2)Under some conditions does MTT colorimetric assay be a susceptible, simple and convenient method for detecting the cytotoxicity of immunocytes.

[Dendritic cells transfected with carcinoembryonic antigen-vaccinia recombinant virus induces CEA-specific immunity mediated by cytotoxic T lymphocytes in vitro].

OBJECTIVE: To observe whether dendritic cells (DCs) transfected with carcinoembryonic antigen (CEA)-vaccinia recombinant virus (rV-CEA) induces cytotoxic T lymphocyte-mediated CEA-specific immunity in vitro. METHODS: DCs derived from peripheral blood monocytes were transfected with rV-CEA and then cocultured with autologous T cells. The proliferation of the induced T cells and their cytotoxic activity against CEA-secreting tumor cells were assessed and compared with those of T cells induced by DCs without rV-CEA transfection. RESULTS: T cells induced by DCs transfected with rV-CEA showed specific cytotoxicity against CEA-secreting tumor cells. CONCLUSION: DCs transfected with rV-CEA can elicit activation of CEA-specific T cells.

[Rapid serum-free culture of dendritic cells from human peripheral blood monocytes and their intracellular signal transduction].

OBJECTIVE: To explore the methods for rapid in vitro culture of the dendritic cells (DCs) from human peripheral blood monocytes (PBMCs) under serum-free conditions and ascertain whether intracellular signal transduction pathway differs between calcium ionophore (CI) and tumor necrosis factor (TNF)- alpha during their induction of dendritic cell differentiation. METHODS: PBMCs isolated from healthy donors were plated in serum-free medium supplemented with 50 ng/ml rhGM-CSF. Cells cultured overnight were induced to differentiate with 100 ng/ml A23187 or 50 ng/ml TNF-alpha, given before or 30 min after pre-treatment with 0.5 mug/ml cyclosporine A (CsA). After culture for 40 h, the cell morphology was observed under phase-contrast microscope, and the surface markers on treated PBMCs were analyzed by flow cytometry. MTT colorimetry was employed to assess the proliferation of the allogeneic T cells. RESULTS: PBMCs of healthy donors treated with 50 ng/ml rhGM-CSF in combination with 100 ng/ml CI or 50 ng/ml TNF-alpha for 40 h exhibited typical morphology of DCs with rapidly decreased CD14 expression and increased expressions of CD83 and co-stimulatory molecules (CD80 and CD86), showing also enhanced ability of stimulating allogeneic T cell proliferation. Calcineurin antagonist CsA inhibited the differentiation induced by CI, but not that induced by TNF-alpha. CONCLUSIONS: Under serum-free conditions, both CI and TNF-alpha are capable of inducing rapid DC differentiation from human PBMCs, but the intracellular signal transduction of CI-induced differentiation is different from that induced by TNF-alpha.

[Effect of immunocyte therapy on benzene-induced bone marrow haemopoietic dysfunction].

OBJECTIVE: To explore the effect of treatment with immunocyte therapy on benzene-induced haemopoietic dysfunction. METHODS: Mono-nuclear cells (MNC) were separated from 40 - 50 ml peripheral blood in patients and mixed with interleukin-2 and granulocyte macrophage colony stimulating factor (GM-CSF) for six day cultivation. The new formed immunocytes were collected and transfused into the patients. Bone marrow aspiration and biopsy were taken before and after therapy for all patients with severe benzene poisoning. Blood samples were stained by flow cytometry for detecting CD(4) and CD(8) positive cells. RESULTS: Of 20 patients with chronic benzene poisoning, 9 were severe benzene poisoning. All examination including blood count, bone marrow biopsy and T cell subpopulation restored to normal after immunocyte therapy. Laboratory tests (liver and kidney function, and myocardial enzymes) were observed periodically and showed normal during therapy. Follow-up study (the longest time was more than 15 months) showed that bone marrow haemopietic function of all treated patients were in normal range. CONCLUSION: Bone marrow haemopoietic dysfunction caused by benzene poisoning may be closely related to disorder of immune function. Immunocyte therapy may significantly improve bone marrow haemopoietic dysfunction induced by benzene poisoning.

[Adriamycin enhances the sonodynamic effect of chlorin e6 against the proliferation of human breast cancer MDA-MB-231 cells in vitro].

OBJECTIVE: To evaluate the effect of adriamycin (ADM) in enhancing the sonodynamic effect of chlorin e6 against the proliferation of human breast cancer MDA-MB-231 cells in vitro. METHODS: MDA-MB-231 cells were treated with ultrasound/Chlorin e6 alone or in combination with ADM, and the changes in the cell proliferation was determined by MTT assay. RESULTS: Ultrasound (1.0 MHz) at the power intensity of 0.5-2.0 W/cm2 inhibited the proliferation of MDA-MB-231 cells in an intensity-dependent manner, and chlorin-e6 (0.05-1.6 mg/ml) and ADM (0.1-0.4 g/ml) alone both inhibited the proliferation of MDA-MB-231 cells dose-dependently. Compared with ultrasound (0.5 W/cm2, 1.0 MHz, 60 s) or chlorin-e6 (0.05-0.2 mg/ml) alone, a combined treatment with ultrasound and chlorin e6 significantly enhanced the inhibitory effect on the proliferation of MDA-MB-231 cells (P<0.05). ADM significantly enhanced the sonodynamic effect of chlorin e6 (0.1 mg/ml) against the cell proliferation of MDA-MB-231 cells (P<0.05), and the effect was schedule-dependent, which was greater when ADM was added after the sonodynamic treatment (P<0.05). CONCLUSION: ADM can enhance the sonodynamic effect of chlorin e6 against the proliferation of MDA-MB-231 cells in vitro.

[The effect of calcium ionophore on dendritic cells derived from peripheral blood mononuclear cells].

AIM: To explore the effect of calcium ionophore (CI) on dendritic cells (DC) derived from peripheral blood monocytes. METHODS: Peripheral blood monocytes from healthy donors were treated with 100 microg/L rhGM-CSF, 100 microg/L rhGM-CSF plus (10 microg/L) CI, and 100 microg/L rhGM-CSF plus (100 microg/L) respectively. After cultivation of 40 hours, cellular morphology was observed under light microscope and electron microscope. Surface markers on treated PBMCs were analyzed by flow cytometry. MTT colorimetry was used to detect proliferation of autologous T cells. RESULTS: Peripheral blood monocytes treated with 100 microg/L rhGM-CSF plus 100 microg/L CI for 40 hours showed typical morphology of DCs. Simultaneously there was a decrease in CD14 expression and increase in HLA-DR, CD40, CD83 and CD86 expressions on these cells. In addition, PBMCs treated with 100 microg/L rhGM-CSF pass 100 microg/L CI for 40 hrs. Could evidently stimulate proliferation of autologous T cells. CONCLUSION: CI can markedly enhance transformation of peripheral blood monocytes induced by GM-CSF into DCs.

[Signal transduction in the differentiation of human peripheral blood mononucleocytes towards dendritic cells induced by calcium ionophore].

AIM: To explore the intracellular signal transduction pathway in the differentiation of human peripheral blood mononucleocytes (PBMCs) towards dendritic cells (DCs) induced by calcium ionophore (CI). METHODS: PBMCs isolated from a healthy donor were cultured with A23187 plus rhGM-CSF, 100 microg/L each. In some experiments, PBMCs were cultured for 30 minutes with W-7 (10 micromol/L), CsA(0.5 mg/L) or KT5926(1 micromol/L) before addition of rhGM-CSF and A23187. After culture for 40 hours, morphological change of the cells were observed under phase contrast microscope; surface markers on treated PBMCs were analyzed by flow cytometry; the proliferation of allogeneic human T cells stimulated by the treated PBMCs was detected by MTT colorimetry. RESULTS: PBMCs of the healthy donor cocultured with rhGM-CSF plus CI for 40 hours had the typical morphology of DCs, with decreased CD14 expression, and increased CD83, CD80 and CD86 expressions. The proliferation of allogeneic T cells stimulated by PBMCs treated with A23187 plus rhGM-CSF was strengthened. But the morphological changes, surface marker expressions and the ability to enhancing proliferation of allogeneic T cells were inhibited to different degrees by W-7, CsA or KT5926. CONCLUSION: The differentiation of PBMCs towards DCs by CI may be modulated by Ca (2+)/calmodulin and multiple signal transduction pathways downstream.