Abstract:

Objective

To clarify the correlation between the m RNA level of 1B(KIF1B),one member of the kinesin family,and clinicopathologic factors in breast cancer,and to evaluate its clinical value in predicting the prognosis of breast cancer patients.

Methods

Real-time reverse transcription-polymerase chain reaction (RT-PCR)was used to detect the mRNA expression level of KIF1B in primary invasive ductal carcinoma in 180 cases.Receiver Operating Characteristic(ROC)curve was used to identify the cut-off value of KIF1B mRNA level to group the patients.Chi-square test was used to compare the differences between/among groups.Survival analysis was carried out according to Kaplan-Meier analysis.Log-rank test was used to compare the differences of survival between groups.Multivariate Cox proportional hazards regression model was used to evaluate KIF1B mRNA level for predicting the prognosis of breast cancer patients.

Results

No significant differences in KIF1B m RNA levels were found between/among groups with different clinicopathologic status.Five-year disease-free survival and metastasis-free survival of patients with low KIF1B were significantly lower than those with high KIF1B(χ²=4.714,P=0.030;χ²=4.393,P=0.036),while three-year disease-free survival and metastasis-free survival between these two groups were not found significantly different.The KIF1B status,clinical stage,histological grade,PR status were independent prognostic factors of breast cancer by analysis of Multivariate Cox proportional hazards regression model.Patients with low KIF1B had higher risk of distant metastasis than patients with high KIF1B(hazard ratio=3.53,95%CI=1.54-8.08,P=0.003).

Conclusion

The under-expressed KIF1B mRNA is correlated with poor prognosis in breast cancer patients,and is an independent molecular marker for predicting prognosis of breast cancer patients.

Key words: Breast neoplasmas, KIF1B, Quantitative RT-PCR