Tracking in vivo migration and distribution of antigen-specific cytotoxic T lymphocytes by 5,6-carboxyfluorescein diacetate succinimidyl ester staining during cancer immunotherapy / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Killing of targeted tumors during adoptive cell transfer therapy is associated with cytotoxic T lymphocyte (CTL) numbers, immunophenotype, tumor-specificity, and in vivo residence time, migration, and distribution. Therefore, tracing in vivo persistence, migration, and distribution of CTLs is important for cancer immunotherapy.</p><p><b>METHODS</b>Optimal staining concentration for CTL proliferation was determined by cell counting kit-8 (CCK-8) assay and killing efficiencies of CTLs or carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled melanoma antigen-specific cytotoxic T lymphocytes (CFSE-CTLs) for malignant melanoma cells in vitro were compared. Additionally, CFSE-CTLs were intravenously transfused to mice receiving B16 melanoma, and their residence time, migration, and distribution in vivo were observed by measuring fluorescence intensities of CFSE-CTLs per gram of tissue (%FI/g) in various tissues and analyzing tumor/non-tumor (T/NT) values. Anti-tumor effects of transferred CTLs and correlation between %FI/g and D-value of tumor size were analyzed.</p><p><b>RESULTS</b>Five-micromolar CFSE was optimal for labeling CTLs with minimal cytotoxicity. No significant difference occurred between CTLs and CFSE-CTLs for tumor cell killing (P = 0.849) or interleukin-2 (P = 0.318) and interferon-γ (P = 0.201) levels. Distribution of CTLs in vivo varied with time. A negative correlation between %FI/g in tumors and D-value of tumor sizes by Spearman correlation analysis was observed. CTLs were recruited to and killed tumors from 6 hours to 3 days after cell infusion. CTLs were observed up to three weeks later in the tumor, liver, kidneys, and spleen; this was related to the abundant blood supply or the nature of immune organs.</p><p><b>CONCLUSIONS</b>CCK-8 assay is a novel method to select optimal CFSE staining concentrations. Fluorescence intensity of transferred CTLs reflects their killing efficiency of tumors. CFSE fluorescent markers can trace in vivo CTL persistence, migration, and distribution because of its stability, long half-life, and low toxicity.</p>

A procedure to assist achievement of total mesorectal excision through the extending intersphincteric plane / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the value of assisted achievement total mesorectal excision (TME) through the extending intersphincteric plane.</p><p><b>METHODS</b>From February 2006 to April 2010, 65 patients with low rectal cancer underwent assisted implementing TME through the extending intersphincteric plane under direct vision and achieved sphincter preservation. The clinical data was summarized and analyzed retrospectively. Follow-up visits were conducted on complications and oncological outcomes.</p><p><b>RESULTS</b>The mean operation time was (245 ± 42) minutes, and the mean intraoperative blood loss was (114 ± 76) ml. There was no postoperative mortality. Postoperative complications included 2 cases of anastomotic leak, 13 cases of anastomotic stenosis, 2 cases of early postoperative inflammatory ileus, 1 case of urinary tract infection, and 1 case of incision infection. Distal margins and circumferential resection margin of all specimens were negative. For pathological stage, there were 26 cases at stage pTNMI, 17 cases at stage pTNMII and 22 cases at stage pTNMIII. The mean follow-up time was (47.9 ± 18.9) months. 10 patients were lost to follow up, 15 cases had distant metastasis or local recurrence in, and 8 cases died of tumor metastasis at the latest follow up. Local recurrence occurred in 3 cases, including recurrence in presacral region, metastasis of lymph node at the left side in pelvis cavity, and metastasis at the sacrum at 35, 36, and 52 months postoperatively. There was no anastomotic recurrence. Log-rank survival analysis showed 5-year cumulative survival rate was 100%, 93.3%, and 63.1% in TNM stage I, II, and III, respectively. The cumulative disease-free survival rate was 96.2%, 83.3%, 44.8% in TNM stage I, II, and III, respectively.</p><p><b>CONCLUSION</b>It has a good oncological effect and was an advantageous procedure to assist achievement total mesorectal excision (TME) through the extending intersphincteric plane as surgeons encountered with difficulties from transabdominal TME.</p>

Methods of isolation, expansion, differentiating induction and preservation of human umbilical cord mesenchymal stem cells / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>This literature review aims to summarize the methods of isolation, expansion, differentiation and preservation of human umbilical cord mesenchymal stem cells (hUCMSCs), for comprehensive understanding and practical use in preclinical research and clinical trials.</p><p><b>DATA SOURCES</b>All the literature reviewed was published over the last 10 years and is listed in PubMed and Chinese National Knowledge Infrastructure (CNKI). Studies were retrieved using the key word "human umbilical cord mesenchymal stem cells".</p><p><b>RESULTS</b>Explants culture and enzymatic digestion are two methods to isolate hUCMSCs from WJ and there are modifications to improve these methods. Culture conditions may affect the expansion and differentiating orientations of hUCMSCs. In addition, hUCMSCs can maintain their multi-potential effects after being properly frozen and thawed.</p><p><b>CONCLUSION</b>Considering their multi-potential, convenient and non-invasive accessibility, low immunogenicity and the reported therapeutic effects in several different preclinical animal models, hUCMSCs have immense scope in regeneration medicine as a substitute for MSCs derived from bone marrow or umbilical cord blood.</p>

Effective adoptive transfer of haploidentical tumor-specific T cells in B16-melanoma bearing mice / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Adoptive transfer of allogeneic tumor-specific T cells often results in severe graft-versus-host disease (GVHD). Here, we sought to maximize graft-versus-tumor and minimize GVHD by using haploidentical T cells in pre-irradiated B16-melanoma bearing mice.</p><p><b>METHODS</b>C57BL/6 mice bearing B16-melanoma tumors were irradiated with 0, 5, or 7 Gy total body irradiation (TBI), or 7 Gy TBI plus bone marrow transplantation. Tumor areas were measured every 3 days to assess the influence of irradiation treatment on tumor regression. B16-melanoma bearing mice were irradiated with 7 Gy TBI; sera and spleens were harvested at days 1, 3, 5, 7, 9, 11, and 13 after irradiation. White blood cell levels were measured and transforming growth factor β1 (TGF-b1) and interleukin 10 (IL-10) levels in serum were detected using enzyme-linked immunosorbent assay (ELISA) kits. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry were performed to test TGF-b1, IL-10 and Foxp3 mRNA levels and the proportion of CD4+CD25+Foxp3+ T-regulatory cells (Tregs) in spleens. B16-melanoma bearing C57BL/6 mice were irradiated with 7 Gy TBI followed by syngeneic (Syn1/Syn2) or haploidentical (Hap1/Hap2), dendritic cell-induced cytotoxic T lymphocytes (DC-CTLs) treatment, tumor areas and system GVHD were observed every 3 days. Mice were killed 21 days after the DC-CTLs adoptive transfer; histologic analyses of eyes, skin, liver, lungs, and intestine were then performed.</p><p><b>RESULTS</b>Irradiation with 7 Gy TBI on the B16-melanoma-bearing mice did not influence tumor regression compared to the control group; however, it down-regulated the proportion of Tregs in spleens and the TGF-b1 and IL-10 levels in sera and spleens, suggesting inhibition of autoimmunity and intervention of tumor microenvironment. Adoptive transfer of haploidentical DC-CTLs significantly inhibited B16-melanoma growth. GVHD assessment and histology analysis showed no significant difference among the groups.</p><p><b>CONCLUSION</b>Adoptive transfer of haploidentical tumor-specific T cells in irradiation-pretreated B16-melanoma bearing mice preserved antitumor capacity without causing a GVHD response.</p>

Therapeutic effects of signal transducer and activator of transcription 3 siRNA on human breast cancer in xenograft mice / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Signal transducer and activator of transcription 3 (STAT3) is usually constitutively activated in a variety of malignancies. It directly contributes to tumorigenesis, invasion, and metastasis. The surgical treatment of breast cancer has made no breakthroughs in terms of treatment effect, in spite of its long history. Current biotherapies bring a note of optimism to breast cancer treatment. To explore the possibility of a siRNA targeted STAT3 blocking treatment for over-activated tumor cells, we evaluated the efficacy of a STAT3 siRNA on human breast cancer cells in vitro and in vivo.</p><p><b>METHODS</b>Three MCF-7 human breast cancer cell lines were tested: control MCF-7 cells, non-specific siRNA transfected MCF-7 cells and STAT3 siRNA transfected MCF-7 cells. Expression of STAT3 in MCF-7 cells was inhibited by RNA interference (RNAi). The STAT3 mRNA and protein levels were detected by semi-quantity RT-PCR and Western blotting. Cell proliferation and apoptosis were determined by MTT method and flow cytometry. The three groups of MCF-7 cells mentioned above were transplanted subcutanuously into nude mice and their tumorgenic ability observed. The STAT3 mRNA and protein levels of the samples from tumors in different groups were determined by semi-quantity RT-PCR and Western blotting and compared.</p><p><b>RESULTS</b>In STAT3 siRNA transfected MCF-7 cells, the expressions (STAT3/β-actin) of STAT3 mRNA (0.327 ± 0.020) and protein (0.153 ± 0.006) were significantly lower than that in control MCF-7 cells (mRNA 1.093 ± 0.018, protein 1.374 ± 0.022) and non-specific siRNA transfected MCF-7 cells (mRNA 1.035 ± 0.050, protein 1.320 ± 0.033) (P < 0.05). MTT showed that cell proliferation was significantly reduced and the cell growth inhibition ratio in the STAT3-siRNA group was (44.00 ± 5.10)%, significantly higher than that in non-specific siRNA transfected MCF-7 cells ((16.10 ± 1.05)%, P < 0.05). Flow cytometry results showed that more apoptosis was observed in the STAT3-siRNA group. The rate of apoptosis was (14.79 ± 0.22)%, much higher than in control MCF-7 cells (7.06 ± 0.71) and non-specific siRNA transfected MCF-7 cells (8.45 ± 0.43) (P < 0.05). The tumor growth in the STAT3 siRNA transfected MCF-7 cells was significantly slower than in the two control groups. On the 22th day after transplantation the tumor weight ((21.40 ± 10.57) mg) and volume ((41.15 ± 12.17) mm(3)) in the STAT3 siRNA transfected group were significantly lower than in control group (weight (88.60 ± 12.16) mg, volume (118.45 ± 24.68) mm(3)) and non-specific siRNA transfected group (weight (57.20 ± 21.86) mg, volume (101.36 ± 21.90) mm(3)) (P < 0.05). Both the STAT3 mRNA and protein levels in the tumors from the STAT3 siRNA transfected group were significantly lower than in the tumors from the two control groups.</p><p><b>CONCLUSIONS</b>STAT3 siRNA can effectively silence the STAT3 gene in vitro and in vivo, increase cell apoptosis rate and significantly decrease cell proliferation, which inhibits the growth of breast cancer cell in vitro. Tumor growth of xenograft mice is significantly inhibited. The results obtained in vivo are in consistency with those in vitro. STAT3 may be a novel therapeutic target for breast cancer and RNA interference has potential clinical application.</p>

Growth inhibition of breast cancer cells in vitro and in vivo by siRNA targeting signal transducers and activators of transcription 3 / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To observe the effect of signal transducers and activators of transcription 3 (STAT3) gene silence on the growth of breast cancer cell line MCF7 in vitro and in vivo and discuss the feasibility and effectiveness of STAT3 used as gene therapeutic target for breast cancer.</p><p><b>METHODS</b>Human breast cancer cell line MCF7 cells were divided into 3 groups: mock control group, control group transfected with scrambled sequence siRNA, and experimental group transfectod with STAT3 siRNA. The STAT3 mRNA and protein levels were detected by semi-quantity RT-PCR and Western blotting, respectively. The cell proliferation and apoptosis were examined by MTT method and flow cytometry. MCF7 cells treated with STAT3-siRNA were transplanted subcutaneously in nude mice and their tumorgenic ability was observed. The STAT3 mRNA and protein levels of the samples from nude mice of different groups were detected by semi-quantity RT-PCR and Western blotting and compared.</p><p><b>RESULTS</b>After treatment with STAT3-siRNA, STAT3 mRNA (0.327 ± 0.020 vs. 1.035 ± 0.050, 1.093 ± 0.018) and ptotein (0.153 ± 0.006 vs. 1.320 ± 0.033, 1.374 ± 0.022) levels in the MCF7 cells transfected with STAT3-siRNA were significantly lower than that in the two control groups (P < 0.05). MTT assay showed that after transfection of the STAT3-siRNA into MCF7 cells, cell proliferation was significantly reduced and the cell growth inhibition ratio in the STAT3-siRNA group was (44.00 ± 5.10)%, significantly higher than that in the control group (16.1 ± 1.05)% (P < 0.05). Flow cytometry results suggested that more apoptosis was observed in the STAT3-siRNA group. The apoptosis rate was (14.79 ± 0.22)%, much higher than that in the control group [(7.06 ± 0.71)%, (8.45 ± 0.43)%, P < 0.05]. The tumor growth in the experimental group was significantly slower than that in the two control groups. 0n the 22th day after transplantation, the tumor weight [(21.4 ± 10.6) mg vs. (88.6 ± 12.2) mg, (57.2 ± 21.9) mg] and volume [(41.15 ± 12.17) mm³ vs. (118.45 ± 24.68) mm³, (101.36 ± 21.90) mm³] in the experimental group were significantly lower than that in the two control groups (P < 0.05). The STAT3 mRNA and protein levels of the samples from nude mice in the experimental group were significantly lower than that in the two control groups.</p><p><b>CONCLUSION</b>siRNA targeting STAT3 can inhibit the proliferation of MCF7 cells in vitro and in vivo. STAT3 may become a novel therapeutic target for breast cancer.</p>

Experimental study of individualized cancer immunotherapy based on dendritic cells against gastric cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the antitumor effects of cytotoxic T lymphocytes (CTLs) induced by autologous dendritic cells that were inspired by autologous tumor lysates (ATLs-mDCs).</p><p><b>METHODS</b>Primary gastric cancer cells prepared by short-term culture were used as targets. ATLs-mDCs were subjected to activate autologous T cells to generate CTLs. The immunological functions of DCs were evaluated by flow cytometry and by mixed leukocyte response (MLR) assay. The antitumor outcome of tumor antigen specific CTLs was tested by cytotoxicity assay. Concentrations of IL-12 in cultured DCs and INF-gamma in CTLs were measured by ELISA.</p><p><b>RESULTS</b>The expressions of MHC-II, CD80, CD83 and CD86 were significantly up-regulated in ATLs-mDCs, moreover, the ATLs-mDCs obtained the capability of stimulating the proliferation of autologous T cells with high efficiency. The secretion of IL-12 in ATLs-mDCs was significantly higher than that in pure mature DCs (t = 15.47, P < 0.01) and in immature DCs (t = 28.44, P < 0.01). The secretion of INF-gamma in CTLs activated by ATLs-mDCs was significantly higher than that in CTLs by pure mature DCs (t = 4.84, P < 0.05) and in CTLs by immature DCs (t = 13.74, P < 0. 01). The antigen specific cytotoxicity of CTLs induced by ATLs-mDCs was significantly higher against autologous tumor cells [(84 +/- 11)%] than that against two allogeneic tumor cell lines [(19 +/- 7)% and (19 +/- 11)%; t = 54.18 and 56.46, P < 0.01, respectively].</p><p><b>CONCLUSIONS</b>ATLs-mDCs might mediate the antigen specific CTLs against autologous gastric cancer cells ex vivo with high efficiency.</p>

Inhibition of K-RAS~(Asn12) Expression by Vector-based RNA Interference in Human Pancreatic Cancer Cell Line / 中国生物工程杂志

To silence the expression of K-RASAsn12 in human pancreatic cancer cell line by vector-based RNAi(RNA interference) technique,two single-strand DNA sequences encoding mutant-specific shRNA (short haipin RNA) for K-RASAsn12 were synthesized and then inserted into pSilenCircle. The recombinant plasmid was called pSC-K-RASAsn12. According to the same method, pSC-GFP encoding shRNA for GFP was gained. Both recombinant plasmids were transfected into human pacreatic cancer cell line AsPC-1 and BxPC-3. The expression level of K-RASAsn12 was detected by semi-quantitative RT-PCR and Western blot. The result indicated that the recombinant plasmid edcoding mutant-specific shRNA for K-RASAsn12 can inhibit significantly the expression of K-RASAsn12 without affection of wild-type K-RAS(K-RASWT)in Human Pancreatic Cancer Cell Line.

Clinical significance of micrometastasis in lymph nodes and microinvasion in primary lesion in submucosal gastric cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To clarify the clinicopathologic characteristics of micrometastasis in lymph nodes and microinvasion in primary lesion for the treatment options with regard to submucosal gastric cancer.</p><p><b>METHODS</b>1945 lymph nodes and 68 primary tumors resected from 79 patients with submucosal gastric cancer were examined. Two consecutive sections were prepared for simultaneous staining with HE and immunostaining with anti-cytokeratin antibody (CAM 5.2), respectively.</p><p><b>RESULTS</b>The incidence of nodal involvement in 79 patients with submucosal gastric cancer was increased from 13% (10/79 patients) by HE staining to 34% (27/79 patients) by cytokeratin immunostaining. Micrometastasis in the lymph nodes were found in 17 of 69 patients (25%) with cancer-free nodes examined by HE staining. Microinvasion to the muscularis properia was found in 11 of 68 patients (16%) who were histologically diagnosed as submucosal gastric cancer. Survival analysis demonstrated a worse 5-year survival in the patients with micrometastasis in lymph nodes (82%) and with microinvasion to muscularis properia (73%). A higher incidence of nodal involvement was found in submucosal cancers of large size (> 2 cm; 43%), a depressed type (48%), lymphatic invasion (73%), and deeper submucosal invasion (submucosal 3; 53%). A higher incidence of microinvasion was found with the diffused-type carcinoma (33%).</p><p><b>CONCLUSIONS</b>Cytokeratin immunostaining is useful for detecting micrometastasis and microinvasion in submucosal gastric cancer. Tumor size, microscopic type, lymphatic invasion, and the depth of submucosal invasion are strongly associated with lymph node involvement. Micrometastasis in lymph nodes and microinvasion in primary lesion indicate an unfavorable outcome of the patients with submucosal gastric cancer.</p>