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Supplementary Figure 3 - PDF file 63K, Supplementary Fig.S3. Overexpression of PHLPP1 or PHLPP2 abrogated the miR-224-mediated regulation of of the cell-cycle regulators

Supplementary Figure 2 - PDF file 68K, Supplementary Fig.S2. Inhibition of miR-224 changes the expression of cell cycle regulators

Supplementary Data - PDF file155K, Supplementary data, including Supplementary methods, Supplementary figure legends, and Supplementary Tables

Purpose: To investigate the clinicopathologic significance, role, and mechanism of action of microRNA-224 (miR-224) in colorectal cancer.Experimental Design: Real-time PCR was used to quantify miR-224 expression. The association of miR-224 with the clinicopathologic features and survival was evaluated in 110 colorectal cancer patients. The role of miR-224 in colorectal cancer was investigated using in vitro and in vivo assays. Luciferase reporter assays were conducted to confirm target gene associations.Results: miR-224 was overexpressed in colorectal cancer. High-level expression of miR-224 was significantly associated with an aggressive phenotype and poor prognosis. Overexpression of miR-224 promoted colorectal cancer cell proliferation in vitro and tumor growth in vivo. Specifically, miR-224 accelerated the G1–S phase transition through activation of AKT/FOXO3a signaling, downregulation of p21Cip1 and p27Kip1, and upregulation of cyclin D1. Moreover, both PH domain leucine-rich-repeats protein phosphatase 1 (PHLPP1) and PHLPP2, antagonists of PI3K/AKT signaling, were confirmed as bona fide targets of miR-224. miR-224 directly targeted the 3′-untranslated regions of the PHLPP1 and PHLPP2 mRNAs and repressed their expression.Conclusion: This study reveals functional and mechanistic links between miRNA-224 and the tumor suppressors PHLPP1 and PHLPP2 in the pathogenesis of colorectal cancer. miR-224 not only plays important roles in the regulation of cell proliferation and tumor growth in colorectal cancer, but also has potential as a prognostic marker or therapeutic target for colorectal cancer. Clin Cancer Res; 19(17); 4662–72. ©2013 AACR.

Supplementary Figure 4 - PDF file 157K, Supplementary Fig.S4. Correlations between miR-224 and PHLPP1 and PHLPP2 expression in clinical CRC tissue samples

Supplementary Figure 1 - PDF file 138K, Supplementary Fig.S1. miR-224 promotes human CRC cell growth and proliferation

Background Long non-coding RNAs (lncRNAs) have been identified to play an important role in the development and progression of various tumors, including colorectal cancer (CRC). However, the regulatory molecular mechanism by lncRNA in CRC initiation and progression has not been fully clarified. Methods TCGA database was used to identify the involvement of LINC01354 in CRC. qRT-PCR and western blot were used to determine RNA and protein expression. The gain- and loss-of-function assays were conducted to explore the function of LINC01354 in the progression of CRC. In order to investigate the LINC01354-mediated mRNA in CRC tumorigenesis, we applied the profiling analysis as well as GO and KEGG analysis. Pulldown and RIP assays were applied to detect the interaction of hnRNP-D with LINC01354 and β-catenin. Results The upregulation of LINC01354 in CRC and its prognostic significance were identified by TCGA database and confirmed in CRC tissues. Functionally, forced expression of LINC01354 promoted, while knockdown of LINC01354 inhibited cell proliferation, migration and EMT phenotype formation of CRC cells. A significant enrichment of the Wnt/β-catenin signaling pathway genes under LINC01354 overexpression. In addition, LINC01354 modulated the mRNA stability of β-catenin through interacting with hnRNP-D, thereby activating Wnt/β-catenin signaling pathway. Conclusions Our investigations proposed novel regulatory axis of LINC01354/hnRNP-D/Wnt/β-catenin, which might be in favor of exploring novel therapeutic regimens for the clinical treatment of CRC. Electronic supplementary material The online version of this article (10.1186/s13046-019-1150-y) contains supplementary material, which is available to authorized users.

The Leucine zipper tumor suppressor gene 1 (LZTS1/FEZ1) gene was originally identified as a potential tumor suppressor. However, the expression pattern and the role of LZTS1 in the progression of colorectal cancer (CRC) have not been well characterized. Herein, we reported that LZTS1 was markedly reduced in CRC tissues compared with matched adjacent normal intestine epithelial tissues. In analysis of 160 CRC specimens, we revealed that decreased expression of LZTS1 was correlated to aggressive characteristics and poor survival of patients with CRC. Moreover, we found that expression of LZTS1 in CRC cells significantly inhibited cell proliferation in vitro and prohibited tumor growth in vitro. On the contrary, silence of LZTS1 promoted cell proliferation and tumor growth in CRC cells. Furthermore, we demonstrated that LZTS1 inhibited cell proliferation and tumor growth in CRC in part via suppression of AMT–mTOR, subsequently down-regulating p27Kip and up-regulating cyclin D1. These findings suggest that LZTS1 plays a potential tumor suppressor role in CRC progression and represents a valuable clinical prognostic marker of this disease.

Metastasis is the major cause of death in colorectal cancer (CRC). Although multiple genes have been identified to be responsible for the development of CRC, the molecular changes that enable CRC cells to undergo early local invasion and to form distant metastatic colonies still remain largely unknown. Herein, we investigated the role of Forkhead box protein C2 (FOXC2) and explored the underlying mechanisms in invasion and metastasis of CRC. We show that both high FOXC2 expression and nuclear localization of FOXC2 are significantly correlated with advanced TNM (T=primary tumor; N=regional lymph nodes; M=distant metastasis) stages. FOXC2 enhanced the invasive abilities of CRC cells in vitro and promoted local invasion and distant metastasis in an orthotopic mouse metastatic model of CRC. Microarray analysis revealed that overexpression of FOXC2 increased the proto-oncogene MET tyrosine kinase expression and activated the hepatocyte growth factor (HGF)-MET signaling pathway. Furthermore, luciferase reporter assays and chromatin immunoprecipitation assays revealed that FOXC2 directly associated with MET promoter to increase the transcriptional activity of MET. Inhibition of MET attenuates the invasive phenotype and metastatic potential of FOXC2-overexpressing CRC cells, indicating that MET is a major mediator of FOXC2-promoted metastasis. In addition, FOXC2 expression was positively correlated with MET expression in CRC tissue samples. Our findings suggest that FOXC2 has a crucial role in CRC metastasis by regulating HGF-MET signaling via inducing MET expression, highlighting FOXC2 as a potential therapeutic target for preventing or reducing metastasis in CRC.

Boolean functions with a variety of secure cipher properties are the key factors to design cryptosystem with the ability to resist multiple cipher attacks and good safety performance. In this paper, using the derivative of the Boolean functions and the e-derivative defined by ourselves as the main research tools, we study algebraic immunity, correlation immunity and other cryptographic properties of the quadratic rotation symmetric Boolean functions. We determine the quadratic rotation symmetric Boolean functions which are H Boolean functions, and the range of weight distribution of the quadratic rotation symmetry H Boolean functions. Besides, we get the compatibility among propagation, balance, correlation immunity and algebraic immunity of the quadratic rotation symmetry H Boolean functions, and also focus on the relationship of balance, correlation immunity and dimension. Furthermore, we check the existence of the cubic rotation symmetry H Boolean functions, and obtain the relationship between existence and dimension of the cubic rotation symmetry H Boolean functions. Moreover, we obtain a more convenient method for solving annihilator. Such researches are important in cryptographic primitive designs, and have significance and role in the theory and application range of cryptosystems.

Background Radiotherapy is an efficient remedy in the treatment of hepatocellular carcinoma (Hca); however, some cancer cells can still survive from the radiation and the therapeutic effect is to be improved. Regulatory T cell (Tregs)–induced tumor tolerance and Akt expression play important roles in the tumor survival. This study aims to elucidate the role of radiation induces Akt expression in Tregs. Methods A rat Hca model was developed. Hca tissue was collected from the rats with or without radiotherapy. The frequency of Treg and apoptotic Treg in Hca tissue was assessed by flow cytometry. A cell culture model was used to investigate the mechanism by which the tumor-infiltrating Tregs survive from irradiation. Results After radiotherapy, the frequency of Treg was increased in Hca, the frequency of apoptotic Tregs was decreased and the expression of Akt was increased in the remaining Tregs. The results were reproduced in vitro with a cell culture model. The addition of Akt inhibitor blocked the irradiation-induced Treg survival. Tregs with high levels of Akt still preserve the immune suppressor function. Conclusions Akt plays an important role in the radiation-induced tumor-infiltrating Treg survival in Hca.

A best partner selection strategy is proposed in cooperative network coding systems. In the strategy, the cooperated partner set is determined by the basic demand that the partners can decode correctly each other. Then, the best partner is selected from the set, which has the best channel gain among the set. Outage probability is also analyzed, and numerical results show that the proposed scheme can reduce outage probability of cooperative network coding systems effectively.

Background Transducin-like enhancer of Split3 (TLE3) serves as a transcriptional corepressor during cell differentiation and shows multiple roles in different kinds of cancers. Recently, TLE3 together with many other genes involved in Wnt/β-catenin pathway were detected hyper-methylated in colorectal cancer (CRC). However, the potential role and the underlying mechanism of TLE3 in CRC progression remain scarce. Methods Gene expression profiles were analyzed in The Cancer Genome Atlas (TCGA) microarray dataset of 41 normal colorectal intestine tissues and 465 CRC tissues. Western blot and Real-time Quantitative PCR (RT-qPCR) were respectively performed to detect protein and mRNA expression in 8 pairs of CRC tissue and matched adjacent normal mucosa. Immunohistochemistry (IHC) was conducted to evaluate TLE3 protein expression in 105 paraffin-embedded, archived human CRC tissues from patients, whose survival data were analyzed with Kaplan-Meier method. In vitro experiments including MTT assay, colony formation assay, and soft agar formation assay were used to investigate the effects of TLE3 on CRC cell growth and proliferation. Additionally, subcutaneous tumorigenesis assay was performed in nude mice to confirm the effects of TLE3 in vivo. Furthermore, gene set enrichment analysis (GSEA) was run to explore potential mechanism of TLE3 in CRC, and then we measured the distribution of CRC cell cycle phases and apoptosis by flow cytometry, as well as the impacts of TLE3 on MAPK and AKT signaling pathways by Western blot and RT-qPCR. Results TLE3 was significantly down-regulated in 465 CRC tissues compared with 41 normal tissues. Both protein and mRNA expressions of TLE3 were down-regulated in CRC compared with matched adjacent normal mucosa. Lower expression of TLE3 was significantly associated with poorer survival of patients with CRC. Besides, knock down of TLE3 promoted CRC cell growth and proliferation, while overexpression of TLE3 showed suppressive effects. Furthermore, overexpression of TLE3 caused G1-S phase transition arrest, inhibition of MAPK and AKT pathways, and up-regulation of p21Cip1/WAF1 and p27Kip1. Conclusion This study indicated that TLE3 repressed CRC proliferation partly through inhibition of MAPK and AKT signaling pathways, suggesting the possibility of TLE3 as a biomarker for CRC prognosis.

To evaluate the effect of palmitic acid (PA) on oxidative stress and activation of inflammasomes in hepatocytes.To test the dose-dependent effect of PA on normal murine hepatocytes AML12, the cells were treated with 0, 0.15, 0.25 and 0.4 mmol/L of palmitic acid (PA). The cells were also divided into blank control group, 0.25 mmol/L PA group and 0.25 mmol/L PA+N-acetylcysteine (NAC) group to examine the effect of reactive oxygen species (ROS) on the activation of inflammasomes. After 24 h of treatment, lipid accumulation, total ROS, mitochondrial ROS, expression and localization of NOX4, and expressions of inflammasomes and IL-1β were detected in the hepatocytes.Compared with the control cells, PA treatment of the cells significantly increased cytoplasmic lipid accumulation, concentrations of total ROS (12 463.09±2.72 vs 6691.23±2.45, P=0.00) and mitochondrial ROS (64.98±0.94 vs 45.04±0.92, P=0.00), and the expressions of NOX4, NLRP3, ASC, caspase-1, and IL-1β (1603.52±1.32 vs 2629.33±2.57, P=0.00). The mitochondria and NOX4 were found to be co-localized in the cytoplasm. NAC obviously reduced cellular ROS level stimulated by PA (7782.15±2.87 vs 5445.6±1.17, P=0.00) and suppressed the expressions of NLRP3, ASC and caspase-1.PA treatment can stimulate lipid accumulation in hepatocytes and induce oxidative stress through NOX4 and mitochondria pathway to activate inflammasomes and stimulate the secretion of IL-1β.

The band conveyer driven by linear friction is a new device. It can reduce drive size and conveyor belt tensity, and increase delivery capacity. It has feasibility and usability particularly in altering the original conveyer and solving the problems of capacity insufficiency. The technology has brought certain difficulty for engineers, because it has certain difficulty both in theory and in calculation. Therefore, Visual Basic 6.0 programming technology was used to develop a set of “the design system of the band conveyer driven by linear friction.” After being proved in the field, it can completely meet the demands of the design. This paper introduced its main theory or basis in design, so as to provide related technical support to this kind of project.

Glutathione S-transferases (GSTs) are enzymes which expressed in many tissues and play important roles in neutralization of toxic compounds and protecting hosts against cancer. Among several GSTs, Glutathione S-transferases mu (GSTM) has been drawn attention upon the association with the genetic risk for many types of cancers. But whether the GSTM1 polymorphisms confer the susceptibility to colorectal cancer in Asians has not been well established. We searched the PubMed database with GSTM1, polymorphism and colorectal cancer, attempting to identify the eligible studies. In total, 33 case-control studies in Asian populations with 8502 colorectal cancer patients and 13699 controls were included in the current meta-analysis. The association between the polymorphism and susceptibility to colorectal cancer was evaluated by the odds ratio (OR) and 95% confidence intervals (CI). The pooled meta-analysis suggested that GSTM1 null variant was correlated to the colorectal cancer risk in Asians. There was a marginal heterogeneity among these eligible studies. Nevertheless, cumulative meta-analysis observed a trend of an obvious association between the GSTM1 null genotype and colorectal cancer risk in Asians. In summary, the meta-analysis suggested that GSTM1 null polymorphism confer the susceptibility to colorectal cancer in Asians, especially in Chinese populations.

F-box only protein 8 (FBX8), a novel component of F-box proteins, has recently been observed in several malignancies. However, its clinical implication in the progression of gastric cancer still remains unclear. The aim of this study was to explore the role of FBX8 in gastric cancer (GC) and analyze its correlation with tumor progression and prognosis. The expression of FBX8 in GC cell lines and matched pairs of fresh gastric cancer tissues were detected by real-time RT-PCR and Western blotting. Immunohistochemistry was used to analyze clinicopathological patterns of FBX8 in 136 cases of clinical paraffin-embedded GC tissues. A series of functional assays were conducted to evaluate the effect of FBX8 on proliferation and invasion in vitro and metastasis in vivo. FBX8 was markedly down-regulated in GC tissues compared to adjacent normal tissues. Patients with low FBX8 had shorter overall survival time and poor prognosis. Knocking down FBX8 obviously promoted proliferation and invasion in BGC823 cells, while over-expression of FBX8 in SGC7901 and AGS cells had the opposite effects. Moreover, FBX8 was sufficient to suppress metastasis in nude mice. Down-regulation of FBX8 significantly correlates with invasion, metastasis and poor survival time in GC patients. FBX8 may serve as a promising therapeutic target for inhibition of GC metastasis.

Background A proliferation-inducing ligand (APRIL) is a member of the tumor necrosis factor (TNF) super family. It binds to its specific receptors and is involved in multiple processes during tumorigenesis and tumor cells proliferation. High levels of APRIL expression are closely correlated to the growth, metastasis, and 5-FU drug resistance of colorectal cancer. The aim of this study was to identify a specific APRIL binding peptide (BP) able to block APRIL activity that could be used as a potential treatment for colorectal cancer. Methods A phage display library was used to identify peptides that bound selectively to soluble recombinant human APRIL (sAPRIL). The peptides with the highest binding affinity for sAPRIL were identified using ELISA. The effects of sAPRIL-BP on cell proliferation and cell cycle/apoptosis in vitro were evaluated using the CCK-8 assay and flow cytometry, respectively. An in vivo mouse model of colorectal cancer was used to determine the anti-tumor efficacy of the sAPRIL-BP. Results Three candidate peptides were characterized from eight phage clones with high binding affinity for sAPRIL. The peptide with the highest affinity was selected for further characterization. The identified sAPRIL-BP suppressed tumor cell proliferation and cell cycle progression in LOVO cells in a dose-dependent manner. In vivo in a mouse colorectal challenge model, the sAPRIL-BP reduced the growth of tumor xenografts in nude mice by inhibiting proliferation and inducing apoptosis intratumorally. Moreover, in an in vivo metastasis model, sAPRIL-BP reduced liver metastasis of colorectal cancer cells. Conclusions sAPRIL-BP significantly suppressed tumor growth in vitro and in vivo and might be a candidate for treating colorectal cancers that express high levels of APRIL.

Purpose: To investigate the clinicopathologic significance, role, and mechanism of action of microRNA-224 (miR-224) in colorectal cancer. Experimental Design: Real-time PCR was used to quantify miR-224 expression. The association of miR-224 with the clinicopathologic features and survival was evaluated in 110 colorectal cancer patients. The role of miR-224 in colorectal cancer was investigated using in vitro and in vivo assays. Luciferase reporter assays were conducted to confirm target gene associations. Results: miR-224 was overexpressed in colorectal cancer. High-level expression of miR-224 was significantly associated with an aggressive phenotype and poor prognosis. Overexpression of miR-224 promoted colorectal cancer cell proliferation in vitro and tumor growth in vivo. Specifically, miR-224 accelerated the G1–S phase transition through activation of AKT/FOXO3a signaling, downregulation of p21Cip1 and p27Kip1, and upregulation of cyclin D1. Moreover, both PH domain leucine-rich-repeats protein phosphatase 1 (PHLPP1) and PHLPP2, antagonists of PI3K/AKT signaling, were confirmed as bona fide targets of miR-224. miR-224 directly targeted the 3′-untranslated regions of the PHLPP1 and PHLPP2 mRNAs and repressed their expression. Conclusion: This study reveals functional and mechanistic links between miRNA-224 and the tumor suppressors PHLPP1 and PHLPP2 in the pathogenesis of colorectal cancer. miR-224 not only plays important roles in the regulation of cell proliferation and tumor growth in colorectal cancer, but also has potential as a prognostic marker or therapeutic target for colorectal cancer. Clin Cancer Res; 19(17); 4662–72. ©2013 AACR.

To investigate the effects of lentivirus-mediated RNA interference (RNAi) targeting a proliferation-inducing ligand (APRIL) on the chemosensitivity to 5-FU of colorectal cancer cell line LoVo.The lentiviral vector siRNA-APRIL was constructed and verified by PCR and DNA sequencing. LoVo cells were transfected with siRNA-APRIL plasmid, non-targeting siRNA plasmid, or empty plasmid. Forty-eight hours after the transfection, the cells were examined for APRIL expression using Western blot. Seventy-two hours after treatment with 10 µg/ml 5-FU, flow cytometry was used to detect the cell apoptosis and cell cycle changes. The cell growth inhibition rate following 5-FU exposure was detected by MTT assay.PCR analysis and DNA sequencing demonstrated that the RNAi sequence targeting APRIL gene was successfully inserted into the lentiviral vector. siRNA-APRIL transfection resulted in obviously reduced expression of APRIL in LoVo cells. After 5-FU exposure, the apoptosis rate of siRNA-APRIL-transfected cells were increased to (21.12∓3.35)%, significantly higher than that in cells transfected with the non-targeting plasmid or the empty plasmid [(13.06∓1.92)% and (12.28∓1.79)%, respectively, P0.01]; the cell number in G0/G1 phase increased while that in G2/M phase decreased in siRNA-APRIL-transfected cells. The growth inhibition rate in siRNA-APRIL group was (59.67∓5.03)%, significantly higher than that in the other two groups [(42.33∓4.16)% and (39.67∓4.73)%, respectively, P0.01].Lentivirus-mediated RNAi targeting APRIL can effectively suppress the expression of APRIL in LoVo cells and enhance the chemosensitivity of the cells to 5-FU.

To observe the effect of selective cyclooxygenase-2 (COX-2) inhibitor on the healing of experimental gastric ulcer in rats and explore its mechanisms in light of gastric acid secretion.Gastric ulcers were induced in rats by an application of acetic acid to the serosal surface of the anterior gastric body. The effects of selective COX-2 inhibitor, celecoxib, on the healing of gastric ulcer, the total acidity of gastric juice, the expressions of H+, K+-ATPase mRNA and protein, and the ultrastructure of the parietal cell were observed in comparison with the effects of normal saline.Nine days after ulcer induction, the ulcer area was 11.9-/+3.1 mm square and 19.7-/+3.8 mm square in rats with normal saline and celecoxib treatments, respectively (P0.01). The total acidity of gastric juice and the expressions of H+, K+-ATPase mRNA and protein in celecoxib group were significantly higher than that in normal saline group at both 6 and 9 days after ulcer induction, but no significant difference was found between the two groups in the amount of secretary canaliculus and microvillus.Selective COX-2 inhibitor can significantly delay the healing of experimental gastric ulcer in rats, the mechanism of which might be associated with enhanced digestive action of gastric acid on the new granulation tissue at the ulcer base as a result of celecoxib-stimulated gastric acid secretion of the parietal cells.

To examine the effect of combined use of curcumin and catechin on the number of aberrant crypt foci (ACF) and expression levels of cyclooxygenase-2 (COX-2) mRNA in rat colon carcinogenesis. Methods Dimethylhydrazine (DMH)-induced rats colon carcinogenesis model was used for evaluation of the synergistic inhibitory effect between curcumin and catechin in light of ACF formation and tumor incidence. COX-2 mRNA expression was also detected in rat colon carcinogenesis.Curcumin, catechin and their co-treatment caused significant inhibition of DMH-induced ACF and colon carcinogenesis as compared with untreated DMH-induced rat models (P0.01). Co-treatment with curcumin and catechins caused greater inhibition of DMH-induced ACF and colon carcinogenesis than the single use of curcumin or catechin (P0.05). A synergistic inhibitory effect between curcumin and catechin on the expression of COX-2 mRNA was observed in the early stage of rat colon carcinogenesis but not in colon tumor tissues.Curcumin and catechin have synergistic effect on ACF and COX-2 mRNA expression in rat colon carcinogenesis, suggesting their potential value in the prevention of human colon cancers.

To investigate the relationship between gastric dysmotility, gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT) were measured by radioimmunoassay in all the subjects. G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa.

To gain insight into the putative anticancer effect of the antibacterial peptides, cecropins, from Chinese oak silkworm, Antheraea pernyi, on the cancer cells and 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis in rats.Growth inhibitory effect of the cecropins on normal human gastric epithelial cell line (GES-1) and human colon adenocarcinoma cell line (LS-174T) was observed using a microculture tetrazolium (MTT) colorimetric methods. Male Wistar rats were divided into 4 groups. Group1 was given on a weekly basis cecropins from Antheraea pernyi (3,000 Ua/ml) by gavage at 2 doses of 10 ml/kg body weight and exposed to subcutaneous injection of DMH at the dose of 20 mg/kg body weight. Group 2 was received weekly DMH only. Group 3 was given the cecropins by gavage at the same dose as in group 1. Group 4 was weekly exposed to subcutaneous injection of EDTA (1 mmol/L). All treatments were completed in a course of 18 weeks and the experiment was finished at week 33.MTT assay showed selective cytotoxic activity of the cecropins against the human colon adenocarcinoma cells line. The viability of the cancer cells was about 54% and 100% for the normal cells. There was a significantly lower incidence of large intestinal tumors in rats gavaged with cecropins (65%, P0.01), but the tumor burden (tumors/tumor-bearing animal) and tumor mass index were comparable between the groups (P0.05).The cecropins possess effective anti-tumor activity with no cytotoxicity against normal eukaryotic cells, and impede the neoplastic process in murine large intestines.

To observe the ultrastructural changes of the endocrine cells in the antrum after the onset of Helicobacter pylori (Hp) infection.Seven patients with chronic gastritis were included in this study, and toluidine blue staining and rapid urease test were performed to determine the Hp status of the gastric antral mucosa biopsies. Five patients identified as being positive for Hp constituted the test group, leaving the 2 Hp-negative patients serving as control. The endocrine cells in the antrum of the patients were sampled to observe the ultrastructural changes by transmission electron microscopy (TEM).TEM showed increased electron density of the secretion granules in the endocrine cells, and secretions in the parietal cells were active.The ultrastructural changes of the endocrine cells in the antrum might explain high gastrin levels after the onset of Hp infection.