Predictive value of TUBB3 and MAPT expression in patients with non-small cell lung cancer receiving chemotherapy with taxanes

DAI Hongyu; LI Suyi; MA Guodong; WAN Mingyue; YU Cunjun; CHEN Wenping

Abstract：Objective To explore the expressions of class Ⅲ β?tubulin ( TUBB3 ) and microtubule associated protein?tau ( MAPT) in tumor tissue of patients with non?small cell lung cancer( NSCLC) , and to evaluate the value of TUBB3 and MAPT in pre?dicting the chemosensitivity of taxanes. Methods The tumor tissue specimens from 55 patients with chemo?naive and unoperable meta?static or recurrent NSCLC were collected. All patients received platinum?taxanes chemotherapy as the first?line therapy. According to the efficacy assessed after two cycles, 55 patients were divided into 3 groups. Patients with complete remission or partial remission were classed as sensitive group, and patients with stable disease were less sensitive group, and patients with progressive disease were resist?ance group. Reverse transcription polymerase chain reaction was used to measure the mRNA levels of TUBB3 and MAPT, and the cor?relation between mRNA expression of TUBB3 and MAPT were analyzed. The immunohistochemistry was used to detect the protein ex?pression levels of TUBB3 and MAPT. Results Expression of TUBB3 and MAPT mRNA in 55 cases of NSCLC tissues were obesrved in varying degrees. TUBB3 and MAPT protein were located in cytoplasm. In sensitive group, less sensitive group and resistance group, the levels of TUBB3 mRNA were 0?12±0?13, 0?17±0?24 and 0?51±0?19 and the levels of MAPT mRNA were 0?09±0?05, 0?14±0?09 and 0?46±0?21, respectively. The positive expression rates of TUBB3 and MAPT were 22?22%(4/18) and 16?67%(3/18) in sensi? <br> tive group, 20?00%(5/20) and 25?00%(4/20) in less sensitive group, and 70?59%(12/17) and 52?94%(9/17) in resistance group. The mRNA levels and positive expression rates of both TUBB3 and MAPT were higher in resistance group versus other two groups(P<0?05). No significant difference were observed on the above indices between sensitive group and less sensitive group(P>0?05). There was a positive correlation between the mRNA expression of TUBB3 and MAPT(r=0?219, P=0?047). Conclusion The expression of TUBB3 and MAPT might predict the chemosensitivity of taxanes in patients with NSCLC. Patients with high expres?sion of TUBB3 and MAPT might show resistance to taxanes. Combined detection of TUBB3 and MAPT might be more valuable in pre?dicting chemosensitivity to taxanes.