Expression Of Smac And MDM2and Their Correlation With Helicobacter Pylori L-form Infection In Gastric Carcinoma

Objective: To research the expression and clinical significance of Smac、MDM2in humangastric cancer (GC) tissues;To analysis the correlation with the expression of Smac、MDM2and their mRNA and Helicobacter pylori L（Hp-L）-form infection and mutualrelations among the three.Methods:(1) Use the IHC(Immunohistochemical staining) with Elivision method to detect theexpression of Smac protein and MDM2protein in100cases of gastric cancer tissues(gastric cancer group) and40cases of normal gastric mucosas margin tissues (controlgroup).(2) Use the gram staining method and IHC (Immunohistochemical staining) with Elivisionmethod to detect the infection of Hp-L in100cases of gastric cancer tissues (gastriccancer group) and40cases of normal gastric mucosas margin (control group).(3) Use semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) todetecte the expression of Smac、MDM2mRNA in30cases of fresh gastric cancer tissueand the normal gastric mucosas margin (control group).Results:(1) The results of Smac:1)The result of IHC showed that the expression of Smac protein ingastric cancer group was (31.0%,31/100)lower than that in control group (62.5%,25/40)(P <0.05)，and the expression level was significantly correlated with infiltration depth、lymph node metastasis、degree of differentiation (P <0.05), not related with the ageand sex (P>0.05).2)RT-PCR results showed that the amount of Smac mRNA expressedin the gastric cancer tissues was lower than that expressed in the normal control group(P <0.05); and the expression level was significantly correlated with infiltration depth、lymph node metastasis、degree of differentiation (P <0.05), not related with the sex andage (P>0.05).(2)1)The results of MDM2:1)The result of IHC showed that the expression of MDM2protein in gastric cancer group wa（s71.0%,71/100）,and it higher than that in control group(42.5%,17/40)(P <0.05)，and the expression level was significantly correlated withinfiltration depth、lymph node metastasis、degree of differentiation (P <0.05), but was not related with the age and sex (P>0.05).2)RT-PCR results showed that the amount ofMDM2mRNA expressed in the gastric cancer tissues was significantly higher than thatexpressed in the normal control group (P <0.05) and the expression level was related withinfiltration depth、lymph node metastasis、degree of differentiation (P <0.05), not relatedwith the age and sex(P>0.05).(3)Hp-L test results: the gram stain:100cases of gastric cancer tissues detected Hp-Lpositive rate was79.0%(79/100), Use IHC detected Hp-L positive detection rate was76.0%(76/100), the testing results of the two methods are consistent (P>0.05); So70cases of Hp-L positive in100cases of gastric cancer tissue,(define gram stain L detectionand detected with immunohistochemical staining positive Hp-L was) at the same time, thepositive rate was70.0%.2) control group19cases of gram staining detected Hp-L,positive rate was47.5%(19/40). IHC detection,17cases Hp-L positive detection rate was42.5%(17/40), also has consistency with gram stainings (P>0.05).40cases of controlgroup in the Hp-L checked out in13, detection rate was32.5%(13/40), visible in gastriccancer group and positive rate of Hp-L was obviously higher than that of control group,the difference is statistically significant (P <0.05); After statistics analysis in gastriccancer group Hp-L just associated with the lymph node metastasis of gastric cancer (P <0.05); not related with the the size of the lump in gastric cancer, cancer cell differentiationdegree, infiltration depth and TNM staging, associated with patient’s age and gender is not(P>0.05).(4)In gastric cancer group, The correlation analysis showed that there was negativecorrelation between the protein of Smac and MDM2.(r=-0.429,P<0.05)(5) In gastric carcinoma the Smac protein positive rate was25.00%in the group that Hp-Lform was positive and it was lower than that in the group in which the Hp-L form wasnegative.And the infection of Hp-L form was negatively related with the expression ofSmac protein (r=-0.316,P<0.05).(6) Gastric cancer tissues Hp-L positive group also positive expression of MDM2in59casesof Hp-L negative groups and MDM2expressed in negative cases of18cases. Inspectionby the Spearman rank correlation analysis found that Hp-L infections and the expressionof MDM2was positively correlation (r=0.447, P <0.05).Conclusion:(1) Smac mRNA expression level in Gastric cancer tissues significantly lower than normalgastric tissues, and MDM2mRNA expression level higher than in normal gastric tissues, and both of them not related with gastric cancer cell differentiation degree, infiltrationdepth, and presence of lymph node metastasis, prompt both play an important role in theprocess of gastric carcinoma metastasis;(2) Smac negatively correlated with MDM2, which suggests that they may play an importantrole in the process of tumor cell invasion and metastasis.(3) The high expression of Hp-L in gastric cancer tissues suggested that it may play animportant part in the occerrence and development of gastric cancer.(4) Hp-L form infection was negatively related with the Smac protein expression in thegastric cancer group,and positively related with the MDM2expression,They all involvedin the occurrence, development and metastasis of gastric cancer.