β-tubulinⅢ Expression In Relation To Tumor Response Of Gastric Cancer Patients Treated With Taxane-based Chemotherapy

Objective:Gastric cancer remained one of the most common diseases that threaten human health, in all malignant tumors, the incidence rate ranked fourth, the mortality rate ranked second. In China, due to the low rate of early diagnosis,60%to70%patients missed the opportunity of redical cure at the time of diagnosis. Furthermore, about50%to70%patients occured relapse and metastasis after operation. For these patients, chemotherapy was the main method general accepted in the world. It coulded relieve clinical symptoms and prolonged survival, thus played the role of palliative treatment. However, the overall efficacy of the chemotherapy for advanced gastric cancer was still not satisfactory. Taxanes, including paclitaxel and docetaxel, were active antitumor agent for gastric cancer. But we found that patients with gastric cancer showed great individual difference in the treatment of taxane. A number of studies had shown that the expression of β-tubulinⅢ was related to taxane chemotherapy sensitivity. The purpose of this study was to learn the beta-tubulinⅢ expression in gastric cancer tissues, investigate the relationship between β-tubulinⅢ expression and taxane chemosensitivity, and investigate if β-tubulin III was a predictor of taxane chemosensitivity in patients with gastric cancer, in order to achieve individualized treatment.Methods:This study was a prospective study.Patients diagnosed with advanced gastric cancer in May2010to November2011in Tianjin Medical University Cancer Hospital digestive oncology department. The detection of β-tubulinⅢ was done if patients agreed. Fluorescence quantitative RT-PCR was used to detect B-tubulinⅢ mRNA. Patients who detected β-tubulinIII entered into the trial group, while who didn’t detect β-tubulinⅢ entered into the control group. Trial group in accordance with the expression of β-tubulinⅢ was divided into the low expression group and the high expression group. The low expression group and the control group used taxane-based chemotherapy, while the high expression group used taxane-free chemotherapy.Results:The trial group included40cases,31cases with low beta-tubulinⅢ expression, the low expression rate was77.5%, nine cases with high beta-tubulinⅢexpression, the high expression rate was22.5%. There was no correlation between beta-tubulinⅢ expression and clinical characteristics, such as age, gender, primary tumor location, pathological type. The low β-tubulinⅢ expression group used taxane-based chemotherapy, chemotherapy cycles ranged from2to8, with a median of5cycles, RR45.2%, DCR77.4%, median PFS7.3months and1year progression-free survival20%, median survival11.6months and1year survival rate47%. The control group included31cases, also treated with taxane-based chemotherapy, chemotherapy cycles ranged from2to8, with a median of4cycles, RR22.6%, DCR67.7%, median PFS5.7months and1year progression-free survival17%, median survival11.2months and1year survival rate24%. RR, DCR, PFS, OS of the two group did not reach statistical difference, P=0.106,0.570,0.305,0.402, respectively. The total of patients treated with taxane-based chemotherapy was62cases. Multivariate analysis found that age, sex, tumor location, pathological type and the expression of beta-tubulinⅢ were not independent prognostic factors (P=0.483,0.805,0.232,0.737,0.756, respectively).Conclusion:There was no correlation between beta-tubulinⅢ expression and clinical characteristics,such as age, gender, primary tumor location, pathological type. The β the-tubulinⅢ expression level in gastric cancer tissue may be a good predictor of taxane sensitivity.