| ObjectiveGastric Cancer(GC)is the most common malignant tumor of the digestive tract.At present,few molecular markers are found for early diagnosis,targeted therapy and prognosis predicting.Seeking for new clinical relevant molecular markers becomes the hotspot of GC research.The previous work of our laboratory on the gene expression profiling of GC tissue revealed that gene Cysteine-rich 61(Cyr61/CCN1)was remarkably over expressed in tumor tissue,pericancerous normal appearing tissue and normal gastric mucosa,which may play an important role in GC.In order to prove the results from the gene profiling data,we analyzed the transcription level of Cyr61 in gastric cancer cell lines,fresh tissue and the protein level of Cyr61 in 306 paraffin-embedded samples of GC(128 cases from the young age group;191 cases from the oesophagogastric junction adenocarcinoma,AEG).In recent years,though the morbility and mortality are decreasing,the incidence of GC at the young age and AEG are increasing.Little is known about these two special types of GC.Therefore,we detected the expression of Cyr61 and a panel of other markers which may relate to Cyr61 in these two special types of GC,expecting to verify the significance of Cyr61 in the prognosis of GC.Besides,the expression of microRNA(has-miR-142-Sp)which may regulate Cyr61 was detected in 4 gastric cancer cell lines.Materials and Methods306 cases of GC were collected and reviewed from the archives of the department of pathology in PLA General Hospital during the time period from 1996 to 2005.Tissue array were made.Cases with follow-up information were evaluated to identify valuable prognostic factors.Envision procedure of immunohistochemistry was applied to detect the expression of Cyr61,CD44,CDX2,β-catenin,PTEN,MMP9,HER1,and HER2 on the paraffin-embedded tissue array sections.The expression of Cyr61 at the mRNA level in GC cell lines and fresh tissue samples was detected by using the methods of RT-PCR and Real time PCR.The location of Cyr61 protein was confirmed by immunofluorescence.Fluorescence in situ hybridization(FISH)was used to detect the amplification of HER2 in GC.The transcription level of microRNA in GC cell lines was detected by Real-Time PCR.The results were analyzed statistically with Kaplan-Meier plots and COX proportional hazard model by applying SPSS 13.0 software.The statistical significance level was set at P＜0.05.ResultsThe mean age of GC of the young was 35.6 years with the range from 19 to 40 years.The male to female ratio was 1.91:1.The mean age of the AEG was 59.7 years with the range from 28 to 83 years.The male to female ratio was 8.1:1.121 cases of the young and 54 cases of AEG were followed-up.The longest survival time of the young patient who died of the tumor was 127.2 months,the shortest was 3.4 months.The longest survival time of the AEG patient who died of the tumor was 86 months,the shortest was 3 months.Statistic analysis showed that in the young GC patients,vascular tumor emboli,female,eosinophile infiltration,depth of tumor invasion,large tumor diameter,lymph node metastases,distant metastasis,and late clinical stage were indicators of worse prognosis.In AEG,the depth of tumor invasion,lymph node metastasis,and late clinical stage correlated with poor outcome.The COX analysis revealed that depth of tumor invasion(P=0.0076),lymph node metastasis(P=0.0368),and distant metastasis(P=0.0156)were significantly correlated to the prognosis of GC of the young;depth of tumor invasion (P=0.0458),and lymph node metastasis(P=0.0389)significantly correlated to the prognosis of the AEG.The highest expression of Cyr61 at the mRNA level in 6 GC cell lines was in BGC823,and the lowest was in AGS.The expression level of Cyr61 in GC tissue was much higher than it in the normal tissue.Cyr61 protein was located in cytoplasm,and its expression in the young GC patients was correlated to the WHO classification,Lauren classification,clinical stage,depth of tumor invasion, lymph node metastases,and distant metastases.The expression of Cyr61 in the AEG patients was correlated to the depth of tumor invasion,clinical stage,and shorter survival time(P=0.0001).The expression of Cyr61 was correlated toβ-catenin,MMP9,and HER2 in young GC patients(P value=0.0009,0.0000 and 0.0000,respectively).The high expression ofβ-catenin(P=0.0314),MMP9(P=0.0112),and the loss of PTEN expression(P=0.0216)were associated with lower survival rate of young GC patients.The expression of Cyr61 was correlated to MMP9 in AEG patients (P=0.0368).The expression of MMP9(P=0.0451)was associated with lower survival rate in AEG patients.The COX analysis revealed that the high expression of MMP9 and CD44 in young GC patients and the high expression of MMP9 and Cyr61 in AEG patients were associated with lower survival rate.There was a negative correlation between the expression of hsa-miR-142-5p and Cyr61(P=0.0007).Conclusions1.Cyr61 is highly expressed in GC cell lines BGC823,MGC303,and SGC7901, lowly expressed in AGS.Cyr61 mRNA expressed in GC tissue and pericancerous normal appearing tissue at a high level,which was consistent with the results of gene expression profiling.Cyr61 protein was located at the cytoplasm of GC tumor cell and was highly expressed both in young GC patients and AEG patients.2.The expression of Cyr61 protein was more common in the intestinal type than in the diffuse type of young GC patients,and the expression had positive correlation with clinical stage,β-catenin,MMP9,and HER2.The expression ofβ-catenin,MMP9,and loss of PTEN was correlated to the low survival rate in young GC patient.The high expression of MMP9 and CD44 in young GC patients was associated with lower survival rate.3.The expression of Cyr61 protein in AEG patients showed positive correlation to the clinical stage,and was associated with lower survival rate.MMP9 had low survival rate.The COX analysis revealed that the high expression of MMP9 and Cyr61 in AEG patients was associated with lower survival rate.4.The main histological type of GC in young patients is diffuse type,with female predominance and worse prognosis.Vescular tumor emboli,female, eosinophile infiltration,deep tumor invasion,large tumor diameter,lymph node metastases,distant metastasis,and late clinical stage were indicators of worse prognosis.5.The characteristics of AEG were male predominance,and with the main histological type of tubular adenocarcinoma.Deep tumor invasion,lymph node metastasis,and late clinical stage were bad indicators for prognosis.
|
PDF Full Text Request