ANP32B promotes colorectal cancer cell progression and reduces cell sensitivity to PRAP1 inhibitor through up-regulating HPF1.

ANP32B, a member of the acidic leucine-rich nuclear phosphoprotein 32 family member B, is aberrantly expressed in various cancers, including colorectal cancer. However, the function and mechanism of action of ANP32B in colorectal cancer remain unclear. The present study therefore analyzed the expression of ANP32B and its activity in colorectal cancer patient samples and colorectal cancer cell lines. ANP32B expression was found to be significantly upregulated in colorectal cancer patient samples and cell lines. Upregulation of ANP32B enhanced colorectal cancer cell proliferation and migration, whereas downregulation of ANP32B suppressed colorectal cancer cell proliferation. RNA sequencing analysis of differentially expressed genes in ANP32B silenced colorectal cancer cells showed that histone PARylation factor 1 (HPF1), which protects against DNA damage by interacting with the anti-tumor target PARP1, was significantly downregulated. Luciferase promoter assays testing the regulatory association between ANP32B and HPF1 showed that ANP32B interacted with the HPF1 promoter. Analysis of colorectal cancer samples from The Cancer Genome Atlas showed that ANP32B and HPF1 expression were positively correlated, and recovery assays showed that ANP32B promoted colorectal cancer progression by up-regulating HPF1. Overexpression of ANP32B also reduced the sensitivity of colorectal cancer cells to PARP1 inhibitor, consistent with the oncogenic role of ANP32B. ANP32B may alter the sensitivity of colorectal cancer cells to PARP1 inhibitor via a mechanism associated with the HPF1 gene. In summary, these findings showed that ANP32B acted as a tumor promoter, potentiating both colorectal cancer malignancy and drug resistance. Targeting the ANP32B/HPF1 axis may have benefit for patients with colorectal cancer.

Synthesis and Characterization of an Analgesic Potential Conotoxin Lv32.1.

In our work of screening analgesic peptides from the conotoxin libraries of diverse Conus species, we decoded a peptide sequence from Conus lividus and named it Lv32.1 (LvXXXIIA). The folding conditions of linear Lv32.1 on buffer, oxidizing agent, concentration of GSH/GSSG and reaction time were optimized for a maximum yield of (34.94 ± 0.96)%, providing an efficient solution for the synthesis of Lv32.1. Its disulfide connectivity was identified to be 1-3, 2-6, 4-5, which was first reported for the conotoxins with cysteine framework XXXII and different from the common connectivities established for conotoxins with six cysteines. The analgesic effect of Lv32.1 was determined by a hot plate test in mice. An evident increase in the pain threshold with time illustrated that Lv32.1 exhibited analgesic potency. The effects on Nav1.8 channel and α9α10 nAChR were detected, but weak inhibition was observed. In this work, we highlight the efficient synthesis, novel disulfide linkage and analgesic potential of Lv32.1, which laid a positive foundation for further development of conotoxin Lv32.1 as an analgesic candidate.

Discovery of a maximally charged Weyl point.

The hypothetical Weyl particles in high-energy physics have been discovered in three-dimensional crystals as collective quasiparticle excitations near two-fold degenerate Weyl points. Such momentum-space Weyl particles carry quantised chiral charges, which can be measured by counting the number of Fermi arcs emanating from the corresponding Weyl points. It is known that merging unit-charged Weyl particles can create new ones with more charges. However, only very recently has it been realised that there is an upper limit - the maximal charge number that a two-fold Weyl point can host is four - achievable only in crystals without spin-orbit coupling. Here, we report the experimental realisation of such a maximally charged Weyl point in a three-dimensional photonic crystal. The four charges support quadruple-helicoid Fermi arcs, forming an unprecedented topology of two non-contractible loops in the surface Brillouin zone. The helicoid Fermi arcs also exhibit the long-pursued type-II van Hove singularities that can reside at arbitrary momenta. This discovery reveals a type of maximally charged Weyl particles beyond conventional topological particles in crystals.

Anti-Ovarian Cancer Conotoxins Identified from Conus Venom.

Conotoxins constitute a treasury of drug resources and have attracted widespread attention. In order to explore biological candidates from the marine cone snail, we isolated and identified three novel conopeptides named as Vi14b, Vi002, Vi003, three conotoxin variants named as Mr3d.1, Mr3e.1, Tx3a.1, and three known conotoxins (Vi15a, Mr3.8 and TCP) from crude venoms of Conus virgo, Conus marmoreus and Conus texile. Mr3.8 (I-V, II-VI, III-IV) and Tx3a.1 (I-III, II-VI, IV-V) both showed a novel pattern of disulfide connectivity, different from that previously established for the µ- and ψ-conotoxins. Concerning the effect on voltage-gated sodium channels, Mr3e.1, Mr3.8, Tx3a.1, TCP inhibited Nav1.4 or Nav1.8 by 21.51~24.32% of currents at semi-activated state (TP2) at 10 µmol/L. Certain anti-ovarian cancer effects on ID-8 cells were exhibited by Tx3a.1, Mr3e.1 and Vi14b with IC50 values of 24.29 µM, 54.97 µM and 111.6 µM, respectively. This work highlights the role of conotoxin libraries in subsequent drug discovery for ovarian cancer treatment.

Ghrelin Ameliorates Diabetic Retinal Injury: Potential Therapeutic Avenues for Diabetic Retinopathy.

Ghrelin has anti-inflammatory, antioxidant, and antiapoptotic effects, and it may be beneficial for the treatment of many ophthalmic diseases, such as cataract, uveitis, and glaucoma. Our previous work proved that ghrelin pretreatment reduced the apoptosis of lens epithelial cells induced by hydrogen peroxide, reduced the accumulation of reactive oxygen species (ROS), and effectively maintained the transparency of lens tissue. However, no study has yet investigated the effect of ghrelin on retina. In this study, we conducted in vitro and in vivo experiments to explore the effect of ghrelin on high-glucose- (HG-) induced ARPE-19 cell damage and diabetic retinopathy in streptozotocin-induced diabetic rats. ARPE-19 cells were incubated in a normal or an HG (30 mM glucose) medium with or without ghrelin. Cell viability was measured by 3-(4, 5-dimethylthiazol-3-yl)-2,5-diphenyl tetrazolium bromide assay, and apoptosis was detected by the Hoechst-PI staining assay. Intracellular reactive oxygen species (ROS) production levels within cells were measured using 2',7'-dichlorofluorescein diacetate staining, and the contents of superoxide dismutase and malondialdehyde were measured using relevant detection kits. The expression levels of IL-1ß and IL-18 were measured using an enzyme-linked immunosorbent assay, and those of NLRP3, IL-1ß, and IL-18 were measured using Western blotting. The rat diabetes models were induced using a single intraperitoneal injection of streptozotocin (80 mg/kg). The morphological and histopathological changes in the retinal tissues were examined. The results indicated that ghrelin reduced ROS generation, inhibited cell apoptosis and the activation of NLRP3 inflammasome, inhibited the apoptosis of retinal cells in diabetic rats, and protected the retina against HG-induced dysfunction. In conclusion, ghrelin may play a role in the treatment of ocular diseases involving diabetic retinopathy.

Acoustic non-Hermitian skin effect from twisted winding topology.

The recently discovered non-Hermitian skin effect (NHSE) manifests the breakdown of current classification of topological phases in energy-nonconservative systems, and necessitates the introduction of non-Hermitian band topology. So far, all NHSE observations are based on one type of non-Hermitian band topology, in which the complex energy spectrum winds along a closed loop. As recently characterized along a synthetic dimension on a photonic platform, non-Hermitian band topology can exhibit almost arbitrary windings in momentum space, but their actual phenomena in real physical systems remain unclear. Here, we report the experimental realization of NHSE in a one-dimensional (1D) non-reciprocal acoustic crystal. With direct acoustic measurement, we demonstrate that a twisted winding, whose topology consists of two oppositely oriented loops in contact rather than a single loop, will dramatically change the NHSE, following previous predictions of unique features such as the bipolar localization and the Bloch point for a Bloch-wave-like extended state. This work reveals previously unnoticed features of NHSE, and provides the observation of physical phenomena originating from complex non-Hermitian winding topology.

Demonstration of topological wireless power transfer.

Recent advances in non-radiative wireless power transfer (WPT) technique essentially relying on magnetic resonance and near-field coupling have successfully enabled a wide range of applications. However, WPT systems based on double resonators are severely limited to short- or mid-range distance, due to the deteriorating efficiency and power with long transfer distance. WPT systems based on multi-relay resonators can overcome this problem, which, however, suffer from sensitivity to perturbations and fabrication imperfections. Here, we experimentally demonstrate a concept of topological wireless power transfer (TWPT), where energy is transferred efficiently via the near-field coupling between two topological edge states localized at the ends of a one-dimensional radiowave topological insulator. Such a TWPT system can be modelled as a parity-time-symmetric Su-Schrieffer-Heeger (SSH) chain with complex boundary potentials. Besides, the coil configurations are judiciously designed, which significantly suppress the unwanted cross-couplings between nonadjacent coils that could break the chiral symmetry of the SSH chain. By tuning the inter- and intra-cell coupling strengths, we theoretically and experimentally demonstrate high energy transfer efficiency near the exceptional point of the topological edge states, even in the presence of disorder. The combination of topological metamaterials, non-Hermitian physics, and WPT techniques could promise a variety of robust, efficient WPT applications over long distances in electronics, transportation, and industry.

Experimental Realization of an Extreme-Parameter Omnidirectional Cloak.

An ideal transformation-based omnidirectional cloak always relies on metamaterials with extreme parameters, which were previously thought to be too difficult to realize. For such a reason, in previous experimental proposals of invisibility cloaks, the extreme parameters requirements are usually abandoned, leading to inherent scattering. Here, we report on the first experimental demonstration of an omnidirectional cloak that satisfies the extreme parameters requirement, which can hide objects in a homogenous background. Instead of using resonant metamaterials that usually involve unavoidable absorptive loss, the extreme parameters are achieved using a nonresonant metamaterial comprising arrays of subwavelength metallic channels manufactured with 3D metal printing technology. A high level transmission of electromagnetic wave propagating through the present omnidirectional cloak, as well as significant reduction of scattering field, is demonstrated both numerically and experimentally. Our work may also inspire experimental realizations of the other full-parameter omnidirectional optical devices such as concentrator, rotators, and optical illusion apparatuses.

Ideal Weyl points and helicoid surface states in artificial photonic crystal structures.

Weyl points are the crossings of linearly dispersing energy bands of three-dimensional crystals, providing the opportunity to explore a variety of intriguing phenomena such as topologically protected surface states and chiral anomalies. However, the lack of an ideal Weyl system in which the Weyl points all exist at the same energy and are separated from any other bands poses a serious limitation to the further development of Weyl physics and potential applications. By experimentally characterizing a microwave photonic crystal of saddle-shaped metallic coils, we observed ideal Weyl points that are related to each other through symmetry operations. Topological surface states exhibiting helicoidal structure have also been demonstrated. Our system provides a photonic platform for exploring ideal Weyl systems and developing possible topological devices.

Association of interleukin-22 polymorphisms with the colon cancer: A case-control study.

INTRODUCTION: Interleukin-22 (IL-22), an IL-10 family cytokine produced by T cells and innate lymphoid cells, is implicated in inflammation and tumorigenesis. In this study, we aimed to investigate the association of IL-22 polymorphisms with the colon cancer in a Chinese population. MATERIALS AND METHODS: Five hundred forty colon cancer cases and 540 healthy controls were recruited in the case-control study. The fluorogenic 5' exonuclease assays were used for genotype analysis of three common polymorphisms (-429C/T, +1046T/A and +1995A/C) of the IL-22 gene. RESULTS: Colon cancer cases had a significantly higher frequency of IL-22-429 TT genotype [odds ratio (OR)=1.69, 95% confidence interval (CI)=1.24, 2.30; P=0.001] and -429T allele (OR=1.35, 95% CI=1.14, 1.60; P=0.001) than healthy controls. The findings are still emphatic by the Bonferroni correction (P<0.017). When stratifying by the differentiation of colon cancer, we found that colon cancer cases with poor differentiation had a significantly higher frequency of IL-22-429 TT genotype (OR=1.45, 95% CI=1.02, 2.07; P=0.04). When stratifying by the tumor location, tumor size, growth pattern and TNM stage of colon cancer, we found no statistical association. The IL-22 +1046T/A and IL-22 +1995A/C gene polymorphisms were not associated with colon cancer. CONCLUSION: Our findings suggested that the IL-22 -429C/T gene polymorphisms might be associated with colon cancer.

Experimental Observation of Large Chern Numbers in Photonic Crystals.

Despite great interest in the quantum anomalous Hall phase and its analogs, all experimental studies in electronic and bosonic systems have been limited to a Chern number of one. Here, we perform microwave transmission measurements in the bulk and at the edge of ferrimagnetic photonic crystals. Band gaps with large Chern numbers of 2, 3, and 4 are present in the experimental results, which show excellent agreement with theory. We measure the mode profiles and Fourier transform them to produce dispersion relations of the edge modes, whose number and direction match our Chern number calculations.

Therapeutic effects of signal transducer and activator of transcription 3 siRNA on human breast cancer in xenograft mice.

BACKGROUND: 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. METHODS: 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. RESULTS: In STAT3 siRNA transfected MCF-7 cells, the expressions (STAT3/ß-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. CONCLUSIONS: 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.

Inhibition of proliferation of rabbit lens epithelial cells by S-phase kinase-interacting protein 2 targeting small interfering RNA.

PURPOSE: Improper proliferation of lens epithelial cells is causally related to posterior capsule opacification. In the present study, we investigated whether small interfering RNA (siRNA)-mediated gene silencing of S-phase kinase-interacting protein 2 (Skp2) can be employed to inhibit rabbit lens epithelial cell (rLEC) proliferation by increasing the p27(kip1) level. METHODS: A plasmid containing Skp2 siRNA was used to decrease the high constitutive level of Skp2 protein in rLECs, which can lead to consequent degradation of p27(kip1). Protein expression of Skp2 and p27(kip1) was detected by immunocytochemistry and western blot. Cell viability was measured using the tetrazolium reduction (3-(4,5-dimethylthiazolyl-2-)-2,5-diphenyltetrazoliumbromide [MTT]) assay. Cell proliferation was assayed by cell counts, immunocytochemistry, and western blot by using antibodies against proliferating cell nuclear antigen. RESULTS: Immunocytochemistry and western blot showed a decreased level of Skp2 and increased level of p27(kip1) in cells transfected with pSkp2 siRNA but not in vehicle transfection and uninfected cells. MTT assay showed that cell viability significantly declined in rLECs transfected with Skp2 siRNA. Skp2 siRNA transfected cells showed significantly less 59-bromodeoxyuridine- and proliferating cell nuclear antigen-positive staining compared with control cells. CONCLUSIONS: Skp2 siRNA inhibits cell proliferation and decreases cell viability of rLECs in vitro by suppression of p27(kip1) downregulation. Our findings suggest that siRNA-mediated gene silencing of Skp2 can be a novel gene therapy for posterior capsule opacification induced by LEC abnormal proliferation.

[Growth inhibition of breast cancer cells in vitro and in vivo by siRNA targeting signal transducers and activators of transcription 3].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Ultrasonically activated scalpel versus monopolar electrocautery shovel in laparoscopic total mesorectal excision for rectal cancer.

AIM: To investigate the feasibility and safety of monopolar electrocautery shovel (ES) in laparoscopic total mesorectal excision (TME) with anal sphincter preservation for rectal cancer in order to reduce the cost of the laparoscopic operation, and to compare ES with the ultrasonically activated scalpel (US). METHODS: Forty patients with rectal cancer, who underwent laparoscopic TME with anal sphincter preservation from June 2005 to June 2007, were randomly divided into ultrasonic scalpel group and monopolar ES group, prospectively. White blood cells (WBC) were measured before and after operation, operative time, blood loss, pelvic volume of drainage, time of anal exhaust, visual analogue scales (VAS) and surgery-related complications were recorded. RESULTS: All the operations were successful; no one was converted to open procedure. No significant differences were observed in terms of preoperative and postoperative d 1 and d 3 WBC counts (P=0.493, P=0.375, P=0.559), operation time (P=0.235), blood loss (P=0.296), anal exhaust time (P=0.431), pelvic drainage volume and VAS in postoperative d 1 (P=0.431, P=0.426) and d 3 (P=0.844, P=0.617) between ES group and US group. The occurrence of surgery-related complications such as anastomotic leakage and wound infection was the same in the two groups. CONCLUSION: ES is a safe and feasible tool as same as US used in laparoscopic TME with anal sphincter preservation for rectal cancer on the basis of the skillful laparoscopic technique and the complete understanding of laparoscopic pelvic anatomy. Application of ES can not only reduce the operation costs but also benefit the popularization of laparoscopic operation for rectal cancer patients.

[The anti-tumor efforts of thymosin alpha1 on tumor lysate-pulsed dendritic cells in colon cancer in vitro and in vivo].

AIM: To investigate the effects of thymosin alpha1 (Talpha1) on the differentiation, maturation and function of tumor lysate-pulsed dendritic cells (LyDCs) in vitro, and to study the antitumor effects on tumor models of the nude mice bearing colon cancer in vivo. METHODS: Immature DCs (imDCs) were prepared routinely from human peripheral blood mononuclear cells. The LyDCs were prepared from the imDCs loaded with lysate of HT-29 tumor cell line. The phenotypes of imDCs and LyDCs pre- or post-stimulated by Talpha1 were analyzed by flow cytometry. Autologous T cells were cocultured with LyDCs in the presence or absence of Talpha1 2 days later. IL-12 secretion of LyDCs and IFN-gamma secretion of the activated T cells in the supernatants were measured by ELISA. The in vitro cytotoxicity of antigen specific cytotoxic T lymphocytes (CTLs) induced by LyDCs which were treated with Talpha1 was evaluated by MTT assay. A humanized nude mice model bearing colon cancer was established. The in vivo antitumor activity was evaluated in the humanized nude mice after the treatment with LyDCs plus Talpha1 or LyDCs alone. RESULTS: The expression levels of HLA-DR, CD80, CD86 and CD83 in imDCs and LyDCs were markedly up-regulated after the stimulation with Talpha1 respectively (P<0.01). The levels of IL-12 and IFN-gamma were also significantly increased in the presence of Talpha1 (P<0.05 and P<0.01, respectively). Cytotoxicity induced by LyDCs treated with Talpha1 was significantly enhanced (P<0.01) as compared with LyDCs in vitro. The humanized cellular immunity was successfully established in the nude mice model. On the 58 th day after the inoculation of tumor cells, the inhibitory rate of tumor growth was significantly higher in the group treated with LyDCs plus Talpha1 than that in the group treated with LyDCs alone (60.41% and 37.20%, respectively; P<0.01). CONCLUSION: Talpha1 can induce the functional maturation of DCs and enhance the immune response of CD4+Th1 arm and cytotoxicity induced by LyDCs. Talpha1 has a synergistic antitumor effect. It might be a promising adjuvant candidate for DC-based immunotherapy of gastrointestinal carcinomas.

[Expression of epithelial cadherin in early gastric cancer and its correlation to lymph node micrometastasis and clinicopathologic features].

BACKGROUND & OBJECTIVE: Lymph node micrometastasis in early gastric cancer is being widely discussed. Cytokeratin (CK) staining is an important way to distinguish epithelial cancer cells. This study was to investigate the correlations of epithelial cadherin (E-cad) expression to lymph node micrometastasis, and clinicopathologic features of early gastric cancer, and to evaluate its clinical significance. METHODS: Morphology of 4522 lymph nodes from 162 patients with early gastric cancer was observed with HE staining and CK immunostaining. E-cad expression in 135 primary lesions of these patients was detected by immunohistochemistry. The correlations of E-cad expression to clinicopathologic features were analyzed. RESULTS: The detection rate of lymph node metastasis by CK staining was significantly higher than that by HE staining (26.5% vs. 6.8%, P<0.001). CK immunostaining detected 32 cases of lymph node micrometastasis which were missed by HE staining. Lymph node micrometastasis was frequently found in primary tumors with a diameter of more than 1.0 cm, in those that were poorly differentiated, deeply invaded (for example, to the submucosa), showed lymphatic or vascular invasion, and in those that showed loss of E-cad expression (P<0.05). The reduced expression rate of E-cad in primary tumor was 57.0%, closely correlated to lymph node micrometastasis. The 5-year survival rate was significantly lower in the patients with lymph node micrometastasis than in those without such metastasis (93.6% vs. 100%, P<0.01). CONCLUSION: Primary tumor more than 1.0 cm in diameter, poor differentiation, deep invasion, lymphatic or vascular invasion, and loss of E-cad expression are risk factors for lymph node metastasis in early gastric cancer.

[In vitro experimental study on individualised immunotherapy induced by dendritic cells transfected with total RNA of autologous gastric cancer cells].

AIM: To explore the efficiency of antitumor immunity induced by autologous dendritic cells (DCs) transfected with total RNA of autologous gastric cancer cells. METHODS: Short-term cultured primary gastric cancer cells were prepared. DCs in peripheral blood mononuclear cells (PBMCs) from gastric cancer patients were induced with rhGM-CSF, rhIL-4 and TNF-alpha. The mature DCs transfected with total RNA of autologous gastric cancer cells were subjected to activate autologous T cells transforming into CTLs, and the activity of CTLs was detected by using CCK-8 kit. The immunological function of DCs were evaluated by flow cytometry and mixed lymphocyte culture(MLC) assay. The levels of IFN-gamma and IL-12 were detected by ELISA. RESULTS: Mature DCs transfected with total RNA of autologous gastric cancer cells not only highly expressed costimulatory molecules (CD80, CD83 and CD86) and (MHC-I and MHC-II), but also powerfully stimulated allogenic or autologous T cell proliferation. The level of IL-12 secreted by mature DCs transfered with tumor RNA was notably higher than those secreted by untransfered and immature DCs, and the rate of killing autologous gastric cancer cells by CTLs was markedly higher than that of killing allogenic tumor cells. CONCLUSION: Mature DCs transfected with autologous gastric cancer cell total RNA can induce and activate high antigen-specific CTLs directed at autologous gastric cancer cells in vitro.

[Clinical significance of micrometastasis in lymph nodes and microinvasion in primary lesion in submucosal gastric cancer].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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%). CONCLUSIONS: 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.