CXCL12-G801A polymorphism modulates risk of colorectal cancer in Taiwan

Introduction

The chemokine CXCL12, designated stromal cell-derived factor-1 (SDF-1), plays a significant role in many cancer metastases. Previous studies have shown that CXCL12-G801A, a single nucleotide polymorphism (SNP) in the 3’ untranslated region, correlates with breast and lung cancer in Iran. The aim of this study was to evaluate the association of the gene variant CXCL12-G801A with colorectal cancer (CRC) in a Taiwanese cohort.

Material and methods

In this study, we used a denaturing high performance liquid chromatography (DHPLC) method to analyze the frequencies of CXCL12-G801A polymorphic variants between CRC patients (n = 258) and healthy controls (n = 300) in Taiwan.

Results

The SNP distribution was higher in CRC patients with TNM stage II (117/258) than healthy controls (52/300). We observed a significant increase in the G/A plus A/A genotype of the CXCL12-G801A polymorphism in CRC patients (45.35%) compared with healthy controls (17.33%). The analysis of allelic frequencies in both groups revealed that CRC patients have a higher frequency of A allele (23.45%) than healthy controls (8.67%). Furthermore, among older CRC patients, the frequency of the CXCL12-G801A genotype was significantly increased (p = 0.0148).

Conclusions

Our observations suggest that the CXCL12-G801A genotype may be associated with some clinical manifestations in CRC patients in Taiwan.     

The CXCR4/CXCL12 axis in endometrial cancer

Chemokines and their receptors seem to act as important regulators of the metastatic cascade. CXCL12 and its receptor CXCR4 were shown to be involved in human cancer progression. There is increasing evidences suggesting that the expression of CXCR4 in human cancers is correlated with poor patient prognosis and that CXCR4 neutralization can prevent metastases in vivo. Here we tested the role of the CXCR4/CXCL12 axis in a neoplasia with a reduced risk of metastatic progression, such as human endometrial cancer. CXCR4 and CXCL12 mRNA expression was measured in 41 endometrial cancers and in corresponding not affected tissues. The expression of CXCR4 was predominant in endometrial cancer (P = 0.035) whereas CXCL12 was overexpressed in normal mucosae (P = 0.002). CXCR4 expression (P = 0.035), but not CXCL12, was significantly related to cancer differentiation. Endometrial cancer cells (HEC1A) were able to generate diffuse metastases in peritoneum, lung and liver of CD-1 nude mice, but the simultaneous treatment with a neutralizing anti-CXCR4 monoclonal antibody dramatically reduced the number and the size of metastases in the animals. In conclusion, our data seem to indicate that the CXCR4-CXCL12 axis can play a role in the progression of endometrial carcinoma and that specific therapies with antagonists of chemokines receptors could be of help in the treatment of metastatic patients.     

Polymorphism and circulating levels of the chemokine CXCL12 in colorectal cancer patients

The chemokine CXCL12, also known as stromal cell-derived factor-1 (SDF-1), is a small protein that regulates leukocyte trafficking and is variably expressed in a number of normal and cancer tissues. CXCL12 as ligand and its receptor CXCR4 have been implicated in colorectal cancer (CRC) progression including angiogenesis and metastasis. A CXCL12 gene variant CXCL12-A (CXCL12-G801A, a single nucleotide polymorphism in the 3' untranslated region) is associated with increased susceptibility to breast cancer. Based on the suggested role of CXCL12 in the pathogenesis of cancer we examined the association of the gene variant CXCL12-A with CRC. The polymorphism was analysed with PCR and RFLP methods. Furthermore, the plasma CXCL12 levels from patients with CRC were also examined. There was no significant difference in genotype distribution and allelic frequencies between CRC patients (n=151) and controls (n=141). On the other hand, we found that the carrying rate of allele CXCL12-A was higher in colon cancer patients compared with rectal cancer patients (P=0.017). Analyses by ELISA showed that CRC patients (n=63) had a lower CXCL12 plasma level compared with controls (P<0.0001). Moreover, patients with tumours classified as Dukes' stage B and C revealed lower levels than patients with tumours in Dukes' stage A. Further studies with larger samples of patients are necessary to determine whether the CXCL12 polymorphism and plasma level reflect the clinical outcome of CRC and have an impact on CRC progression.     

Variable expression of cysteinyl leukotriene type I receptor splice variants in asthmatic females with different promoter haplotypes

Background

TCR and CXCR4-mediated signaling appears to be reciprocally regulated pathways. TCR activation dampens the chemotactic response towards the CXCR4 ligand CXCL12, while T cells exposed to CXCL12 are less prone to subsequent TCR-activation. The heterotrimeric G proteins G_αq and G_αi2 have been implicated in CXCR4-signaling and we have recently also reported the possible involvement of G_αq in TCR-dependent activation of Lck (Ngai et al., Eur. J. Immunol., 2008, 38: 32083218). Here we examined the role of G_αq in migration and TCR activation.

Results

Pre-treatment of T cells with CXCL12 led to significantly reduced Lck Y394 phosphorylation upon TCR triggering indicating heterologous desensitization. We show that knockdown of G_αq significantly enhanced basal migration in T cells and reduced CXCL12-induced SHP-1 phosphorylation whereas G_αi2 knockdown inhibited CXCL12-induced migration.

Conclusion

Our data suggest that G_αi2 confers migration signals in the presence of CXCL12 whereas G_αq exerts a tonic inhibition on both basal and stimulated migrational responses. This is compatible with the notion that the level of G_αq activation contributes to determining the commitment of the T cell either to migration or activation through the TCR.     

CXCR4 inhibition enhances radiosensitivity,while inducing cancer cell mobilization in a prostate cancer mouse model

Preclinical studies show that stroma affects sensitivity of prostate cancer cells via activation of the CXCR4/CXCL12 pathway. Here we studied the effect of CXCR4 inhibition combined with irradiation in prostate cancer cells. In an in vitro co-culture with stromal cells, the CXCR4 inhibitor AMD3100 sensitized prostate cancer cell lines PC3-Luc and LNCaP to irradiation (P = 0.04). Tumor growth and metastasis were evaluated in mice xenografted with luciferase-expressing PC3 cells that received 5 Gy irradiation weekly ± 3.5 mg/kg AMD3100 daily intraperitoneally. The irradiated xenografts showed higher CXCR4 (P = 0.006) and CXCL12 (P = 0.01) expression, compared to controls. AMD3100 sensitized the xenografts to irradiation at the fourth week of treatment (P = 0.02). However AMD3100 also mobilized tumor cells at days 14 and 21 (P < 0.0001), as shown by bioluminescent imaging. In conclusion, AMD3100 transiently enhances prostate cancer radiosensitivity, but induces cancer cell mobilization.     

CXCL12, CXCR4 and IFNγ genes expression: implications for proinflammatory microenvironment of breast cancer

Signals from the microenvironment have a profound influence on the maintenance or progression of breast cancer. In the present study, the frequency of CXCL12 rs1801157 polymorphism in peripheral blood and the expression of CXCL12, CXCR4 and IFNγ mRNA in normal and mammary gland tumor tissues were assessed in breast cancer patients. Genotyping was performed by polymerase chain reaction followed by restriction fragment length polymorphism and expression analyses by quantitative RT-PCR. A lower CXCL12 mRNA relative expression was observed among allele A carriers when compared to GG carriers (p = 0.012). ER-positive breast cancer allele A carriers showed a significantly lower expression of CXCL12 mRNA within tumor tissue than in normal breast tissue when compared to GG ER-positive patients (p = 0.016). CXCR4 mRNA (p < 0.001) and CXCL12 mRNA (p = 0.02) relative expressions were significantly correlated with relative IFNγ mRNA expression. Allele A carriers presenting high levels of IFNγ had a significantly higher expression of CXCR4 mRNA in tumor tissue than GG patients (p = 0.026). It is possible that allele A carrier hormone receptor–positive patients could be more susceptible to metastasis development, since they present a lower CXCL12 expression in tumor tissue, and tumor cells expressing CXCR4 could migrate toward CXCL12 gradient. IFNγ expression increases in order to improve immune response and could favor higher CXCR4 expression leading to migration of cells, possibly of metastatic ones, too.     

胃癌组织中CXCL12和CXCR4的表达及意义

目的观察趋化因子CXCL12及其特异性受体CXCR4在人胃癌组织中的表达,探讨其与临床病理参数、预后的关系。方法选择120例胃癌标本,应用免疫组化SP法检测CXCL12和CXCR4在人胃癌组织中的表达,分析CXCL12和CXCR4的表达与患者临床病理参数、术后生存率之间的关系。结果胃癌组织及正常胃黏膜组织中均可检测到CXCL12、CXCR4的表达,但胃癌组织中的表达水平均明显高于正常胃黏膜组织,表达差异有显著性(P<0.05)。CXCL12阳性与CXCR4阳性呈正相关(r=0.276,P<0.05)。胃癌CXCL12和CXCR4的表达水平与肿瘤细胞淋巴结转移及分化程度密切相关(P<0.05),与患者的年龄、性别、肿瘤的大小、浸润深度及远处转移等无关(P>0.05)。CXCL12和CXCR4阳性表达的患者其五年生存率明显低于其阴性表达的患者。结论胃癌中CXCL12和CXCR4的高表达与胃癌的生物学行为及预后密切相关,检测其表达对预测胃癌的转移及判断预后有一定价值。     

趋化因子及其受体CXCL12/CXCR4在人前列腺癌转移机制中的作用

目的 探讨趋化因子及其受体CXCL12/CXCR4在人前列腺癌转移机制中的作用.方法 免疫组织化学技术分析CXCL12/CXCR4蛋白在18例前列腺癌组织中的表达;免疫细胞化学技术分析CXCL12/CXCR4蛋白在人前列腺癌细胞株PC3、DU145和LNCap中的表达;迁移、侵袭试验分析外源性CXCL12对PC3、DU145和LNCap体外侵袭能力的调节作用.结果 18例人前列腺癌组织中,17例不同强度表达CXCR4蛋白,1例阴性表达,同时除1例标本弱表达CXCL12蛋白外,其余不表达CXCL12蛋白.3种前列腺癌细胞株均表达CXCR4蛋白,不表达CXCL12蛋白.外源性CXCLl2可明显促进PC3、DU145及LNCap的体外迁移、侵袭,以抗CXCL12或CXCR4抗体预处理PC3、LNCap细胞可以拮抗CXCL12对它们的促迁移、侵袭作用.结论 人前列腺癌组织表达CXCR4蛋白,CXCL12/CXCR4信号通路可能参与前列腺癌的侵袭、转移.     

CXCL10 and CXCL13 Expression were Highly Up-regulated in Peripheral Blood Mononuclear Cells in Acute Rejection and Poor Response to Anti-Rejection Therapy

Background  

Acute rejection is still one of the main complications which enhances the cost and the risk to renal graft failure. Chemokines, interacting with respective receptors, can recruit leukocytes into grafts and mediate allograft rejection. In this study, we aimed to analyze gene expression of chemokines including CCL5/RANTES, CXCL10/IP-10, CXCL13/BCA-1, and receptors of CCR5, CXCR3, CXCR5 in peripheral blood mononuclear cells (PBMCs) during acute renal allograft rejection     

Expression of CXCR7 in colorectal adenoma and adenocarcinoma: Correlation with clinicopathological parameters

Colorectal carcinoma (CRC) is one of the most lethal malignancies, it ranks third in cancer-related morbidity and mortality. Although great progress has been made in early diagnosis and combined treatment of CRC, the prognosis of patients remains poor owing to the high rate of recurrence and distant metastasis. CXCR7 belongs to chemokine receptor family and has been identified as a novel receptor for CXCL12. It plays an important role in development and in progression of cancer to metastatic stage.The aim of studyTo evaluate the immunohistochemical expression of CXCR7 in colorectal adenoma and carcinoma and to analyze its correlation with clinicopathological factors. This is retrospective study including 58 colonic adenocarcinoma specimens and 18 cases of colonic adenoma.ResultsCXCR7 showed positive cytoplasmic expression in two out 18 cases of colorectal adenoma (11%) and 42 out of 58 cases of CRC (72.4%) with a significant difference between both (p < 0.001). We found a significant correlation between upregulation of CXCR7 and presence of lymphovascular tumor emboli, presence of lymph node metastasis and advanced TNM stage of the CRC. The association of the CXCR7 with patient age, sex, tumor size, depth of invasion and tumor cell differentiation was found to be non-significant. Regarding colonic adenoma, we found no significant association between CXCR7 expression on one hand and patient age, sex, tumor size, histologic type and degree of dysplasia on the other hand.ConclusionCXCR7 in CRC may act as a novel predictive indicator for prognosis and even be a potential molecular target for anticancer therapies.     

CXCL12-CXCR4 interactions modulate prostate cancer cell migration, metalloproteinase expression and invasion

The mechanisms responsible for prostate cancer metastasis are incompletely understood at both the cellular and molecular levels. In this regard, chemokines are a family of small, cytokine-like proteins that induce motility of neoplastic cells, leukocytes and cancer cells. The current study evaluates the molecular mechanisms of CXCL12 and CXCR4 in prostate cancer cell migration and invasion. We report that functional CXCR4 is significantly expressed by prostate cancer cell lines, LNCaP and PC3, when compared with normal prostatic epithelial cells (PrEC). As measured using motility and invasion chamber assays, prostate cancer cells migrated and invaded through extracellular matrix components in response to CXCL12, at rates that corresponded to CXCR4 expression. Anti-CXCR4 antibodies (Abs) significantly impaired the migration and invasive potential of PC3 and LNCaP cells. CXCL12 induction also enhanced collagenase-1 (metalloproteinase-1 (MMP-1)) expression by LNCaP and PC3 cells. Collagenase-3 (MMP-13) was expressed by prostate cancer cells, but it was not expressed by PrEC cells or modulated by CXCL12. CXCL12 increased MMP-2 expression by LNCaP and PC3; however, MMP-9 expression was elevated only in PC3 cells after CXCL12-CXCR4 ligation. PC3 cells also expressed high levels of stromelysin-1 (MMP-3) after CXCL12 stimulation. CXCL12 also significantly increased stromelysin-2 (MMP-10) expression by LNCaP cells. Stromelysin-3 (MMP-11) was expressed by LNCaP cells, but not by PC3 or PrEC cells and CXCL12 induced PC3 MMP-11 expression. Membrane type-1 MMP (MMP-14) was not expressed by PrEC or LNCaP cells, but CXCL12 significantly enhanced MMP-14 expression by PC3 cells. These studies reveal important cellular and molecular mechanisms of CXCR4/CXCL12-mediated prostate cancer cell migration and invasion.     

CXCR4/CXCL12 expression profile is associated with tumor microenvironment and clinical outcome of liver metastases of colorectal cancer

Interaction between CXCR4 and CXCL12 plays a role in tumor progression. The present study examined CXCR4, CXCL12 and CD133 expression in liver metastases of colorectal cancer (CLM) and determined whether the expression profiles affect the tumor microenvironment and thus progression, and whether they could serve as a prognostic marker for survival. Liver metastases of colorectal cancer collected from 92 patients were evaluated by CXCR4, CXCL12 and CD133 immunohistochemistry and clinicopathological data were analyzed. The expression profile of CXCR4 was determined in the colorectal cancer cell line, SW48. The expression of cytoplasmic CXCR4 was higher in 36 (39%) patients than that indicated by CXCR4 staining intensity of hepatocytes. High levels of nuclear CXCR4 expression in 23 (25%) patients significantly correlated with CXCL12 expression in hepatocytes. Nuclear CXCR4 expression was increased in the cancer cells after exposure to CXCL12. Univariate and multivariate analyses demonstrated that the high levels of nuclear CXCR4 and CXCL12 expression in hepatocytes were significantly better prognostic factors for overall and hepatic disease-free survival in patients with CLM. The expression of CXCR4 and CXCL12 in CLM may have an interactive effect that could alter the tumor microenvironment. CXCR4 expression in metastatic liver tumors together with the upregulation of CXCL12 in hepatocytes may help to predict the clinical outcomes of patients with CLM after hepatectomy.     

人结直肠癌趋化因子配体生物轴及干细胞标志物基因表达与临床病理

背景：趋化因子配体12/趋化因子受体4生物学轴在肿瘤的特异性转移中有重要作用,而干细胞标志物糖蛋白激素受体5基因的表达对于肿瘤的增殖和侵袭转移发挥重要作用。 目的：观察趋化因子配体12/趋化因子受体4生物轴以及干细胞标志物糖蛋白激素受体5基因在人结直肠癌组织中的表达变化及其与临床中的病理特征的关系。 方法：收集2013年1至6月辽宁省肿瘤医院收治100名结直肠癌患者为实验组,100名健康体检者为对照组,采用免疫组织化学SP法检测两组组织中趋化因子配体12、趋化因子受体4及干细胞标志物糖蛋白激素受体5 mRNA表达情况,并分析趋化因子配体12、趋化因子受体4及干细胞标志物糖蛋白激素受体5 mRNA表达与结直肠癌患者年龄、性别、肿瘤大小及部位、淋巴转移以及预后等临床病理特征的相关性。 结果与结论：趋化因子受体4、糖蛋白激素受体5 mRNA在结直肠癌组织中均有较高的表达率,但是趋化因子配体12 mRNA表达率降低。趋化因子受体4、干细胞标志物糖蛋白激素受体5 mRNA、趋化因子配体12 mRNA三者与结直肠癌患者的年龄、性别等患者临床特征无相关性,与结直肠癌的发病位置及其大小也无相关性,与结直肠癌组织是否淋巴转移具有相关性关,伴有淋巴转移的结直肠癌组织中干细胞标志物糖蛋白激素受体5 mRNA和趋化因子受体4的表达率更高,而趋化因子配体12 mRNA表达无显著变化;趋化因子受体4表达随肿瘤的恶性程度增高而增高;糖蛋白激素受体5表达于胃肠道肿瘤和脑肿瘤干细胞等表面,其表达随肿瘤的恶性程度增高而增高。提示结直肠癌组织中趋化因子受体4的表达增高,糖蛋白激素受体5基因表达增高,二者增高促进了结直肠癌组织生长及转移,糖蛋白激素受体5以及趋化因子配体12/趋化因子受体4轴的表达的调控,使其或将成为肿瘤诊断及治疗的重要新靶点。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

Elevated Production of B Cell Chemokine CXCL13 is Correlated with Systemic Lupus Erythematosus Disease Activity

Introduction  

B lymphocyte chemoattractant (BLC/CXCL13), a CXC chemokine, is involved in B1 and B2 cell trafficking for the activation of autoreactive T helper (Th) cells and autoantibody production in target organs during the development of lupus. CXCL13 can induce the trafficking of CXCR5+ T lymphocyte subset designated as follicular helper T lymphocytes (T_FH) which are specifically involved in autoantibody production.     

CXCL12(SDF-1)-CXCR4及CXCL12-CXCR7与胃癌相关性研究进展

胃癌是最常见的恶性肿瘤之一,远处转移是其预后不良的主要原因.既往研究认为CX-CR4是趋化因子CXCL12的唯一受体,CXCL12/CXCR4轴在胃癌的发生发展过程中起着重要作用,然而最近研究表明CXCL12尚存在CXCR7这一新的受体,并且CXCL12/CXCR7轴同样对肿瘤的发生发展起重要作用.     

CXCL12／CXCR4对胰腺癌细胞生物学行为的影响

目的探讨CXCLl2／CXCR4生物轴对胰腺癌细胞增殖、侵袭等生物学行为的影响。方法体外培养胰腺癌细胞系Miapaca-2,将其分为对照组、CXCLl2组和AMD3100组。（1）采用RT—PCR检测胰腺癌细胞中CXCLl2、CXCR4、基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶-9（MMP-9）和人尿激酶型纤溶酶原激活物（uPA）mRNA的表达水平;（2）采用CCK-8法检测各组细胞的增殖情况;（3）采用Transwell侵袭实验检测CXCLl2／CXCR4对胰腺癌细胞趋化活性的影响。结果胰腺癌细胞系Miapaca-2中CXCLl2mRNA未见表达,而CXCR4mRNA在胰腺癌细胞中有表达。MMP-2、MMPO和uPAmRNA在AMD3100组、对照组和CXCLl2组中的表达水平呈递增趋势,差异具有统计学意义（P〈0．05）。胰腺癌细胞的增殖和侵袭能力在CXCLl2组明显增强,而在AMD3100组得到了有效的抑制,组间差异有统计学意义（P〈0．05）。结论趋化因子CXCLl2及其受体CXCR4所构成的生物轴对胰腺癌细胞的增殖和侵袭能力发挥着重要的作用。     

Constitutive expression of growth regulated oncogene (<Emphasis Type="Italic">gro</Emphasis>) in human colon carcinoma cells with different metastatic potential and its role in regulating their metastatic phenotype

The purpose of this study was to examine the expression and functional significance of the growth-regulated oncogene (gro) family in human colon carcinoma growth and metastasis. We examined constitutive expression of CXCL1 (gro-α), CXCL2 (gro-β), CXCL3 (gro-γ) and their receptor, CXCR2 in human colon carcinoma cells with different metastatic potentials. Non-metastatic and low metastatic cells expressed lower levels of CXCL1 and CXCR2 mRNA and protein as compared to high metastatic colon carcinoma cells. No difference in CXCL2 and CXCL3 mRNA expression levels was observed. Colon carcinoma cells expressing higher levels of CXCL1 exhibit increased proliferation and invasive potential. Furthermore, exogenous addition of recombinant human CXCL1 significantly enhanced the proliferation and invasiveness of colon carcinoma cells. Furthermore, treatment of KM12C cells with exogenous CXCL1 enhanced their invasiveness. Neutralizing antibody to CXCL1 in combination with antibody to CXCR2 inhibited highly metastatic KM12L4 (high CXCL1 expressor) cell proliferation. These data demonstrate that the constitutive expression of CXCL1 and its receptor CXCR2 is associated with metastatic potential and modulates colon cancer cell proliferation and an invasive phenotype.This revised version was published online in August 2005 with a corrected cover date.     

CXCL12 is a key regulator in tumor microenvironment of cervical cancer: an in vitro study

CXCL12 is a small pro-inflammatory chemo-attractant cytokine which signals through chemokine receptor CXCR4. The importance of CXCL12/CXCR4 axis is coming to the fore in several divergent signaling pathway-initiating signals related to cell survival and/or proliferation and cancer metastasis. In the present study we have investigated whether deregulation in CXCR4 signaling (as a consequence of deregulated expression of CXCL12) modulate the metastatic potential of cervical carcinoma cells. We demonstrate that CXCL12 is frequently down regulated and its promoter is hypermethylated in cervical cancer cell lines and primary tumor biopsies. Exogenous treatment of cervical cancer cell lines (HeLa, SiHa and C-33A) with recombinant CXCL12 inhibited the metastasis promoting cell migration, cell invasion and anchorage independent cell growth events. Although this study will need further in vivo validation, our observations suggest that (a) silencing of CXCL12 in cervical cancer cells may be critical in migration and invasion, the key events in cancer cell metastases; (b) cervical cancer cells having down regulated CXCL12 are more prone to being attracted to CXCL12 expressed at secondary sites of metastases; and (c) CXCL12 inhibits anchorage independent cell growth via anoikis. These findings suggest the tumor suppressor functions of CXCL12 in cervical cancer.     

Salmonella reduces tumor metastasis by downregulation C-X-C chemokine receptor type 4

Tumor metastasis is the main reason for the death of most cancer patients. C-X-C chemokine receptor type 4 (CXCR4) has been demonstrated to be overexpressed in numerous types of cancer. CXCR4 selectively binds with stromal cell-derived factor 1 (SDF1), also known as C-X-C family chemokine ligand 12 (CXCL12) (CXCL12/SDF-1), which induced tumor proliferation and metastasis. Recently, the use of conventional cancer treatments had some limitation; bacteria treatment for cancer becomes a trend that overcomes these limitations. Plenty of studies show that Salmonella has anti-tumor and anti-metastatic activity. The current study aimed to investigate Salmonella suppresses CXCR4 protein expression and tumor cell migration ability in B16F10 melanoma and LL2 lung carcinoma cells. Salmonella reduced CXCR4 protein expression through downregulating Protein Kinase-B (Akt)/Mammalian Target of Rapamycin (mTOR) signaling pathway. In cells transfected with constitutively active Akt plasmids, a reverse effect of Salmonella-induced inhibition of CXCR4 was observed. Tumor cells have chemotactic response to CXCL12 in migration assay, and we found that Salmonella reduced tumor chemotactic response after CXCL12 treatment. The C57BL/6 mice were intravenously injected with B16F10 and LL2 cells pre-incubated with or without Salmonella, the tumor size and lung weight of Salmonella group had obviously decreased, indicating anti-metastatic effect that confirmed the findings from the in vitro experiments.