AIM: To confirm the anti-invasion and anti-migration effects of down-regulation of Notch1 combined with interleukin(IL)-24 in hepatocellular carcinoma(HCC) cells.METHODS: γ-secretase inhibitors(GSIs) were used to dow...AIM: To confirm the anti-invasion and anti-migration effects of down-regulation of Notch1 combined with interleukin(IL)-24 in hepatocellular carcinoma(HCC) cells.METHODS: γ-secretase inhibitors(GSIs) were used to down-regulate Notch1.Hep G2 and SMMC7721 cells were seeded in 96-well plates and treated with GSI-I or/and IL-24 for 48 h.Cell viability was measured by MTT assay.The cellular and nuclear morphology was observed under a fluorescence microscope.To further verify the apoptotic phenotype,cell cultures were also analyzed by flow cytometry with Annexin V-FITC/propidium iodide staining.The expression of Notch1,SNAIL1,SNAIL2,E-cadherin,IL-24,XIAP and VEGF was detected by Western blot.The invasion and migration capacities of HCC cells were detected by wound healing assays.Notch1 and Snail were downregulated by RNA interference,and the target proteins were analyzed by Western blot.To investigate the mechanism of apoptosis,we analyzed Hep G2 cells treated with si Notch1 or si CON plus IL-24 or not for 48h by caspase-3/7 activity luminescent assay.RESULTS: GSI-I at a dose of 2.5 μmol/L for 24 h caused a reduction in cell viability of about 38% in Hep G2 cells.The addition of 50 ng/m L IL-24 in combination with 1 or 2.5 μmol/L GSI-I reduced cell viability of about 30% and 15%,respectively.Treatment with IL-24 alone did not induce any cytotoxic effect.In SMMC7721 cells with the addition of IL-24 to GSI-I(2.5 μmol/L),the reduction of cell viability was only about 25%.Following GSI-I/IL-24 combined treatment for 6 h,the apoptotic rate of Hep G2 cells was 47.2%,while no significant effect was observed in cells treated with the compounds employed separately.Decreased expression of Notch1 and its associated proteins SNAIL1 and SNAIL2 was detected in Hep G2 cells.Increased E-cadherin protein expression was noted in the presence of IL-24 and GSI-I.Furthermore,the increased GSI-I and IL-24 in Hep G2 cell was associated with downregulation of MMP-2,XIAP and VEGF.In the absence of treatment,Hep G2 cells could migrate into the scratched space in 24 h.With IL-24 or GSI-I treatment,the wound was still open after 24 h.And the distance of the wound closure strongly correlated with the concentrations of IL-24 and GSI-I.Treatment of Notch-1 silenced Hep G2 cells with 50 ng/m L IL-24 alone for 48 h induced cytotoxic effects very similar to those observed in non-silenced cells treated with GSI-I/IL-24 combination.Caspase-3/7 activity was increased in the presence of si Notch1 plus IL-24 treatment.CONCLUSION: Down-regulation of Notch1 by GSI-I or si RNA combined with IL-24 can sensitize apoptosis and decrease the invasion and migration capabilities of Hep G2 cells.展开更多
AIM:To assess the significance of interleukin(IL)-24 and vascular endothelial growth factor(VEGF)expression in lymph-node-positive rectal cancer. METHODS:Between 1998 and 2005,90 rectal adenocarcinoma patients with ly...AIM:To assess the significance of interleukin(IL)-24 and vascular endothelial growth factor(VEGF)expression in lymph-node-positive rectal cancer. METHODS:Between 1998 and 2005,90 rectal adenocarcinoma patients with lymph node involvement were enrolled.All patients received radical surgery and postoperative pelvic chemoradiotherapy of 50.4-54.0 Gy.Chemotherapy of 5-fluorouracil and leucovorin or levamisole was given intravenously during the first and last week of radiotherapy,and then monthly for about 6 mo.Expression of IL-24 and VEGF was evaluated by immunohistochemical staining of surgical specimens, and their relations with patient characteristics and survival were analyzed.The median follow-up of surviving patients was 73 mo(range:52-122 mo). RESULTS:IL-24 expression was found in 81 out of 90 patients;31 showed weak intensity and 50 showedstrong intensity.VEGF expression was found in 64 out of 90 patients.Negative and weak intensities of IL-24 expression were classified as negative expression for analysis.IL-24 expression was significantly reduced in poorly differentiated tumors in comparison with well or moderately differentiated tumors(P=0.004),N2b to earlier N stages(P=0.016),and stageⅢc to stageⅢ a orⅢb(P=0.028).The number of involved lymph nodes was also significantly reduced in IL-24-positive patients in comparison with IL-24-negative ones. There was no correlation between VEGF expression and patient characteristics.Expression of IL-24 and VEGF was not correlated with survival,but N stage and stages were significantly correlated with survival. CONCLUSION:IL-24 expression was significantly correlated with histological differentiation,and inversely correlated with the degree of lymph node involvement in stageⅢrectal cancer.展开更多
The interleukin-17 family is the key group of cytokines and displays a broad spectrum of biological functions,including regulating the inflammatory cascade in various autoimmune and inflammatory diseases,such as multi...The interleukin-17 family is the key group of cytokines and displays a broad spectrum of biological functions,including regulating the inflammatory cascade in various autoimmune and inflammatory diseases,such as multiple sclerosis,neuromyelitis optica spectrum disorder,myasthenia gravis,Guillain–Barre syndrome,acute disseminated encephalomyelitis,diabetes,inflammatory skin diseases,joint inflammation,and cancer.Although the function of the interleukin-17 family has attracted increasing research attention over many years,the expression,function,and regulation mechanisms of different interleukin-17 members are complicated and still only partially understood.Currently,the interleukin-17A pathway is considered a critical therapeutic target for numerous immune and chronic inflammatory diseases,with several monoclonal antibodies against interleukin-17A having been successfully used in clinical practice.Whether other interleukin-17 members have the potential to be targeted in other diseases is still debated.This review first summarizes the recent advancements in understanding the physicochemical properties,physiological functions,cellular origins,and downstream signaling pathways of different members and corresponding receptors of the interleukin-17 family.Subsequently,the function of interleukin-17 in various immune diseases is discussed,and the important role of interleukin-17 in the pathological process of immune diseases is demonstrated from multiple perspectives.Then,the current status of targeted interleukin-17 therapy is summarized,and the effectiveness and safety of targeted interleukin-17 therapy are analyzed.Finally,the clinical application prospects of targeting the interleukin-17 pathway are discussed.展开更多
BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics...BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics of cancer stem cell markers CD24 and CD133 in GC pathological tissues,and to explore their association with patients’clinicopathological parameters and postoperative survival outcomes.METHODS A total of 304 GC patients who underwent surgical treatment in our hospital from January 2018 to January 2020 were retrospectively included.Immunohistochemistry was used to detect the protein expression of CD24 and CD133 in tumor tissues,adjacent tissues,and normal gastric mucosa tissues.Based on staining intensity and the proportion of positive cells,expression levels were classified into low and high expression,while clinicopathological parameters were recorded.χ2 test was used to evaluate the correlation between expression and categorical variables,Spearman rank correlation analysis was performed to assess the correlation between the expression intensities of the two markers,and multivariate regression models were applied to identify independent risk factors influencing co-expression.Kaplan-Meier survival curves and Log-rank test were used to compare survival differences among groups with different expression patterns.RESULTS Among the 304 patients,155 cases(50.99%)were CD24 positive,including 91 low-expression and 64 highexpression;133 cases(43.75%)were CD133 positive,including 81 low-expression and 52 high-expression.There were 74 cases(24.34%)with double positivity and 81 cases(26.64%)with double negativity.Compared with tumor tissues,the positive rates of CD24 and CD133 in normal gastric tissues and adjacent tissues were significantly lower(P<0.05).Univariate analysis showed that co-expression of CD24 and CD133 in GC tissues was significantly correlated with tumor size,Lauren classification,T stage,N stage,and vascular invasion(P<0.05),but not with patient age,gender,tumor site,World Health Organization histological classification,or M stage(P>0.05).Further multivariate regression analysis suggested that tumor size,T stage,N stage,and vascular invasion were independent risk factors promoting CD24 and CD133 double positivity.Spearman rank correlation analysis indicated a moderate positive correlation between their expression intensities(r=0.420,P<0.001).During follow-up,29 of 304 patients were lost(loss rate 9.54%);146 deaths occurred.According to expression combination,there were 89 cases of CD24 single positivity(39 deaths),68 cases of CD133 single positivity(31 deaths),81 cases of double negativity(25 deaths),and 66 cases of double positivity(51 deaths).Log-rank test showed significant differences in overall survival among the four groups(χ2=20.89,P<0.001),with CD24+/CD133+group showing the worst prognosis.CONCLUSION CD24 and CD133 exhibit high positive detection rates in GC tissues,and their co-positivity is closely associated with tumor stage progression and significantly indicates unfavorable survival outcomes.The co-expression of CD24/CD133 may reflect higher aggressiveness and metastatic potential of GC,serving as a potential prognostic marker and a direction for targeted therapeutic strategies.However,as this is a single-center retrospective study with limitations such as patient loss to follow-up and sample size,further prospective,multicenter,and mechanistic studies are required to validate its clinical applicability and biological role.展开更多
Background Pancreatic cancer is a highly malignant tumor affecting an ever increasing number of patients with a mean 5-year survival rate below 4%. Therefore, gene therapy for cancer has become a potential novel thera...Background Pancreatic cancer is a highly malignant tumor affecting an ever increasing number of patients with a mean 5-year survival rate below 4%. Therefore, gene therapy for cancer has become a potential novel therapeutic modality. In this study we sought to determine the inhibitory effects of adenovirus-mediated human interleukin-24 (AdhIL-24) on pancreatic cancer.Methods Human interleukin-24 gene was cloned into replication-defective adenovirus specific for patu8988 tumor cells by virus recombination technology. Reverse transcription-polymerase chain reaction and Western blotting analysis were used to determine the expression of human interleukin-24 mRNA in patu8988 cells in vitro. Induction of apoptosis by overexpression of human interleukin-24 in patu8988 cells was determined by flow cytometry. In vivo efficacy of adenoviral delivery of human interleukin-24 was assessed in nude mice (n=10 for each group) bearing patu8988 pancreatic cancer cell lines by determining inhibition of tumor growth, endothelial growth factor and CD34 expression, and intratumoral microvessel density (MVD).Results The recombinant adenovirus vector AdVGFP/IL-24 was constructed with a packaged recombinant retrovirus titer of 1.0×10^10 pfu/ml and successfully expressed of both mRNA and protein in patu8988 cells. The AdVGFP/IL-24 induced apoptosis of patu8988 tumor cells in vitro and significantly inhibited tumor growth in vivo (P 〈0.05). The intratumoral MVD decreased significantly in the treated tumors (P 〈0.05).Conclusion The recombinant adenovirus AdGFP/IL-24 can effectively express biologically active human interleukin-24, which results in inhibition of pancreatic cancer growth.展开更多
Background:To investigate the regulatory effect of interleukin-24(IL-24)on cell viability of human chorionic trophoblast cell line(HTR-8/SVneo cells).Methods:Immunohistochemical staining was used to detect the express...Background:To investigate the regulatory effect of interleukin-24(IL-24)on cell viability of human chorionic trophoblast cell line(HTR-8/SVneo cells).Methods:Immunohistochemical staining was used to detect the expression of IL-24 and its receptors IL-20R1,IL-20R2,and IL-22R1 in villus tissue at early normal pregnancy.The effect of thymic stromal lymphopoietin(TSLP)and chemokine CCL2 on the expression of IL-24 in human chorionic trophoblast cell line HTR-8/SVneo cells was analyzed by In-cell Western.In addition,the effect of recombinant human IL-24(rhIL-24)and CCL2 on the viability of HTR-8/SVneo cells was analyzed by MTT assay.Results:IL-24 and its receptors showed a strong positive staining in trophoblasts at early normal pregnancy.Compared with control group,expression of IL-24 in HTR-8/SVneo cells was significantly inhibited after in vitro stimulation of recombinant human CCL2 protein(rhCCL2)(P<0.001).The viability of HTR-8/SVneo cells was significantly decreased after treatment with rhIL-24(P<0.001).In contrast,anti-IL-24 neutralizing antibody significantly enhanced the viability of HTR-8/SVneo cells(P<0.01).In addition,rhCCL2(100μg/L);enhanced the viability of HTR-8/SVneo cells(P<0.01)in vitro,but this effect was inhibited by treatment with rhIL-24.Conclusions:CCL2 enhances the viability of human trophoblast cell line HTR-8/SVneo cells in vitro by inhibiting the secretion of IL-24,which may be beneficial to blastocyst implantation and placental development.展开更多
基金Supported by Shandong Provincial Natural Science Foundation,China,No.ZR2012HQ039 and No.ZR2014HP065National Natural Science Foundation of China,No.81373172 and No.81402579
文摘AIM: To confirm the anti-invasion and anti-migration effects of down-regulation of Notch1 combined with interleukin(IL)-24 in hepatocellular carcinoma(HCC) cells.METHODS: γ-secretase inhibitors(GSIs) were used to down-regulate Notch1.Hep G2 and SMMC7721 cells were seeded in 96-well plates and treated with GSI-I or/and IL-24 for 48 h.Cell viability was measured by MTT assay.The cellular and nuclear morphology was observed under a fluorescence microscope.To further verify the apoptotic phenotype,cell cultures were also analyzed by flow cytometry with Annexin V-FITC/propidium iodide staining.The expression of Notch1,SNAIL1,SNAIL2,E-cadherin,IL-24,XIAP and VEGF was detected by Western blot.The invasion and migration capacities of HCC cells were detected by wound healing assays.Notch1 and Snail were downregulated by RNA interference,and the target proteins were analyzed by Western blot.To investigate the mechanism of apoptosis,we analyzed Hep G2 cells treated with si Notch1 or si CON plus IL-24 or not for 48h by caspase-3/7 activity luminescent assay.RESULTS: GSI-I at a dose of 2.5 μmol/L for 24 h caused a reduction in cell viability of about 38% in Hep G2 cells.The addition of 50 ng/m L IL-24 in combination with 1 or 2.5 μmol/L GSI-I reduced cell viability of about 30% and 15%,respectively.Treatment with IL-24 alone did not induce any cytotoxic effect.In SMMC7721 cells with the addition of IL-24 to GSI-I(2.5 μmol/L),the reduction of cell viability was only about 25%.Following GSI-I/IL-24 combined treatment for 6 h,the apoptotic rate of Hep G2 cells was 47.2%,while no significant effect was observed in cells treated with the compounds employed separately.Decreased expression of Notch1 and its associated proteins SNAIL1 and SNAIL2 was detected in Hep G2 cells.Increased E-cadherin protein expression was noted in the presence of IL-24 and GSI-I.Furthermore,the increased GSI-I and IL-24 in Hep G2 cell was associated with downregulation of MMP-2,XIAP and VEGF.In the absence of treatment,Hep G2 cells could migrate into the scratched space in 24 h.With IL-24 or GSI-I treatment,the wound was still open after 24 h.And the distance of the wound closure strongly correlated with the concentrations of IL-24 and GSI-I.Treatment of Notch-1 silenced Hep G2 cells with 50 ng/m L IL-24 alone for 48 h induced cytotoxic effects very similar to those observed in non-silenced cells treated with GSI-I/IL-24 combination.Caspase-3/7 activity was increased in the presence of si Notch1 plus IL-24 treatment.CONCLUSION: Down-regulation of Notch1 by GSI-I or si RNA combined with IL-24 can sensitize apoptosis and decrease the invasion and migration capabilities of Hep G2 cells.
文摘AIM:To assess the significance of interleukin(IL)-24 and vascular endothelial growth factor(VEGF)expression in lymph-node-positive rectal cancer. METHODS:Between 1998 and 2005,90 rectal adenocarcinoma patients with lymph node involvement were enrolled.All patients received radical surgery and postoperative pelvic chemoradiotherapy of 50.4-54.0 Gy.Chemotherapy of 5-fluorouracil and leucovorin or levamisole was given intravenously during the first and last week of radiotherapy,and then monthly for about 6 mo.Expression of IL-24 and VEGF was evaluated by immunohistochemical staining of surgical specimens, and their relations with patient characteristics and survival were analyzed.The median follow-up of surviving patients was 73 mo(range:52-122 mo). RESULTS:IL-24 expression was found in 81 out of 90 patients;31 showed weak intensity and 50 showedstrong intensity.VEGF expression was found in 64 out of 90 patients.Negative and weak intensities of IL-24 expression were classified as negative expression for analysis.IL-24 expression was significantly reduced in poorly differentiated tumors in comparison with well or moderately differentiated tumors(P=0.004),N2b to earlier N stages(P=0.016),and stageⅢc to stageⅢ a orⅢb(P=0.028).The number of involved lymph nodes was also significantly reduced in IL-24-positive patients in comparison with IL-24-negative ones. There was no correlation between VEGF expression and patient characteristics.Expression of IL-24 and VEGF was not correlated with survival,but N stage and stages were significantly correlated with survival. CONCLUSION:IL-24 expression was significantly correlated with histological differentiation,and inversely correlated with the degree of lymph node involvement in stageⅢrectal cancer.
基金supported by the National Natural Science Foundational of China(Key Program),No.U24A20692(to CJZ)the National Natural Science Foundational of China,Nos.82101414(to MLJ),82371355(to CJZ)+4 种基金the National Natural Science Foundational of China for Excellent Young Scholars,No.82022019(to CJZ)Sichuan Special Fund for Distinguished Young Scholars,No.24NSFJQ0052(to CJZ)The Innovation and Entrepreneurial Team of Sichuan Tianfu Emei Program,No.CZ2024018(to CJZ)Funding for Distinguished Young Scholars of Sichuan Provincial People’s Hospital,No.30420230005(to CJZ)Funding for Distinguished Young Scholars of University of Electronic Science and Technology of China,No.A1098531023601381(to CJZ)。
文摘The interleukin-17 family is the key group of cytokines and displays a broad spectrum of biological functions,including regulating the inflammatory cascade in various autoimmune and inflammatory diseases,such as multiple sclerosis,neuromyelitis optica spectrum disorder,myasthenia gravis,Guillain–Barre syndrome,acute disseminated encephalomyelitis,diabetes,inflammatory skin diseases,joint inflammation,and cancer.Although the function of the interleukin-17 family has attracted increasing research attention over many years,the expression,function,and regulation mechanisms of different interleukin-17 members are complicated and still only partially understood.Currently,the interleukin-17A pathway is considered a critical therapeutic target for numerous immune and chronic inflammatory diseases,with several monoclonal antibodies against interleukin-17A having been successfully used in clinical practice.Whether other interleukin-17 members have the potential to be targeted in other diseases is still debated.This review first summarizes the recent advancements in understanding the physicochemical properties,physiological functions,cellular origins,and downstream signaling pathways of different members and corresponding receptors of the interleukin-17 family.Subsequently,the function of interleukin-17 in various immune diseases is discussed,and the important role of interleukin-17 in the pathological process of immune diseases is demonstrated from multiple perspectives.Then,the current status of targeted interleukin-17 therapy is summarized,and the effectiveness and safety of targeted interleukin-17 therapy are analyzed.Finally,the clinical application prospects of targeting the interleukin-17 pathway are discussed.
基金National Natural Science Foundation of China,No.82003223and China Postdoctoral Science Foundation,No.2020M671398.
文摘BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors of the digestive system worldwide,the prognosis of patients with advanced GC remains poor.AIM To evaluate the combined expression characteristics of cancer stem cell markers CD24 and CD133 in GC pathological tissues,and to explore their association with patients’clinicopathological parameters and postoperative survival outcomes.METHODS A total of 304 GC patients who underwent surgical treatment in our hospital from January 2018 to January 2020 were retrospectively included.Immunohistochemistry was used to detect the protein expression of CD24 and CD133 in tumor tissues,adjacent tissues,and normal gastric mucosa tissues.Based on staining intensity and the proportion of positive cells,expression levels were classified into low and high expression,while clinicopathological parameters were recorded.χ2 test was used to evaluate the correlation between expression and categorical variables,Spearman rank correlation analysis was performed to assess the correlation between the expression intensities of the two markers,and multivariate regression models were applied to identify independent risk factors influencing co-expression.Kaplan-Meier survival curves and Log-rank test were used to compare survival differences among groups with different expression patterns.RESULTS Among the 304 patients,155 cases(50.99%)were CD24 positive,including 91 low-expression and 64 highexpression;133 cases(43.75%)were CD133 positive,including 81 low-expression and 52 high-expression.There were 74 cases(24.34%)with double positivity and 81 cases(26.64%)with double negativity.Compared with tumor tissues,the positive rates of CD24 and CD133 in normal gastric tissues and adjacent tissues were significantly lower(P<0.05).Univariate analysis showed that co-expression of CD24 and CD133 in GC tissues was significantly correlated with tumor size,Lauren classification,T stage,N stage,and vascular invasion(P<0.05),but not with patient age,gender,tumor site,World Health Organization histological classification,or M stage(P>0.05).Further multivariate regression analysis suggested that tumor size,T stage,N stage,and vascular invasion were independent risk factors promoting CD24 and CD133 double positivity.Spearman rank correlation analysis indicated a moderate positive correlation between their expression intensities(r=0.420,P<0.001).During follow-up,29 of 304 patients were lost(loss rate 9.54%);146 deaths occurred.According to expression combination,there were 89 cases of CD24 single positivity(39 deaths),68 cases of CD133 single positivity(31 deaths),81 cases of double negativity(25 deaths),and 66 cases of double positivity(51 deaths).Log-rank test showed significant differences in overall survival among the four groups(χ2=20.89,P<0.001),with CD24+/CD133+group showing the worst prognosis.CONCLUSION CD24 and CD133 exhibit high positive detection rates in GC tissues,and their co-positivity is closely associated with tumor stage progression and significantly indicates unfavorable survival outcomes.The co-expression of CD24/CD133 may reflect higher aggressiveness and metastatic potential of GC,serving as a potential prognostic marker and a direction for targeted therapeutic strategies.However,as this is a single-center retrospective study with limitations such as patient loss to follow-up and sample size,further prospective,multicenter,and mechanistic studies are required to validate its clinical applicability and biological role.
基金This work was supported by a grant from the Science Foundation of the Ministry of Health of China (No. WKJ2004-2-011).
文摘Background Pancreatic cancer is a highly malignant tumor affecting an ever increasing number of patients with a mean 5-year survival rate below 4%. Therefore, gene therapy for cancer has become a potential novel therapeutic modality. In this study we sought to determine the inhibitory effects of adenovirus-mediated human interleukin-24 (AdhIL-24) on pancreatic cancer.Methods Human interleukin-24 gene was cloned into replication-defective adenovirus specific for patu8988 tumor cells by virus recombination technology. Reverse transcription-polymerase chain reaction and Western blotting analysis were used to determine the expression of human interleukin-24 mRNA in patu8988 cells in vitro. Induction of apoptosis by overexpression of human interleukin-24 in patu8988 cells was determined by flow cytometry. In vivo efficacy of adenoviral delivery of human interleukin-24 was assessed in nude mice (n=10 for each group) bearing patu8988 pancreatic cancer cell lines by determining inhibition of tumor growth, endothelial growth factor and CD34 expression, and intratumoral microvessel density (MVD).Results The recombinant adenovirus vector AdVGFP/IL-24 was constructed with a packaged recombinant retrovirus titer of 1.0×10^10 pfu/ml and successfully expressed of both mRNA and protein in patu8988 cells. The AdVGFP/IL-24 induced apoptosis of patu8988 tumor cells in vitro and significantly inhibited tumor growth in vivo (P 〈0.05). The intratumoral MVD decreased significantly in the treated tumors (P 〈0.05).Conclusion The recombinant adenovirus AdGFP/IL-24 can effectively express biologically active human interleukin-24, which results in inhibition of pancreatic cancer growth.
基金This study was supported by the National Natural Science Foundation of China(NSFC)(81571509,31671200)the Program for Zhuoxue of Fudan University.
文摘Background:To investigate the regulatory effect of interleukin-24(IL-24)on cell viability of human chorionic trophoblast cell line(HTR-8/SVneo cells).Methods:Immunohistochemical staining was used to detect the expression of IL-24 and its receptors IL-20R1,IL-20R2,and IL-22R1 in villus tissue at early normal pregnancy.The effect of thymic stromal lymphopoietin(TSLP)and chemokine CCL2 on the expression of IL-24 in human chorionic trophoblast cell line HTR-8/SVneo cells was analyzed by In-cell Western.In addition,the effect of recombinant human IL-24(rhIL-24)and CCL2 on the viability of HTR-8/SVneo cells was analyzed by MTT assay.Results:IL-24 and its receptors showed a strong positive staining in trophoblasts at early normal pregnancy.Compared with control group,expression of IL-24 in HTR-8/SVneo cells was significantly inhibited after in vitro stimulation of recombinant human CCL2 protein(rhCCL2)(P<0.001).The viability of HTR-8/SVneo cells was significantly decreased after treatment with rhIL-24(P<0.001).In contrast,anti-IL-24 neutralizing antibody significantly enhanced the viability of HTR-8/SVneo cells(P<0.01).In addition,rhCCL2(100μg/L);enhanced the viability of HTR-8/SVneo cells(P<0.01)in vitro,but this effect was inhibited by treatment with rhIL-24.Conclusions:CCL2 enhances the viability of human trophoblast cell line HTR-8/SVneo cells in vitro by inhibiting the secretion of IL-24,which may be beneficial to blastocyst implantation and placental development.