The Expression And Significance Of MTOR And 4EBP1 In Laryngeal Squamous Cell Carcinoma

Backgrounds and ObjectiveLaryngeal squamous cell carcinoma (LSCC) is the most common malignant tumor in otolaryngology. It accounts for 5%-8% in all the malignant tumors. Many researchers indicated that the incidence of laryngeal squamous cell carcinoma is increasing according to the influence of life style and environment. So far, the exact pathogenesis is still unknown. And the desease may be caused by multiple factors. With the signal transduction pathway in cancer being studyed in the field of molecular biology, the method of treating cancer has become an emerging field of biological treatment by interventing pathway.Mammalian target of rapamycin (mTOR) is a kind of serine and threonine protein kinase. It belongs to phosphatidylinositol kinase family, which exists widely in a variety of biological cells and plays an important role in the signal transduction Process. It also plays a central role in regulating cell growth, proliferation differentiation and survival. Through interacting with other proteins, it regulates some translation initiation. In addition, mTOR can inhibit a variety of stimulation apoptosis and promote the progression of cell cycle, survival and proliferation. It also participates in angiogenesis and plays a very important role in tumor formation and development, as well as tumor invasion and metastasis.Eukaryotic translation initiation factor 4E binding protein 1 (4EBP1) is the first downstream substrate of mTOR, which is a low molecular weight protein as well as a translation inhibitor. It inhibits the translation initiation through the combination with mRNA cap-binding subunit of elF4E. The signal pathway conduction system of mTOR activated abnormaly is closely associated with the occurrence and development of tumor. Some studies have revealed that mTOR signaling pathway conduction system has become an attractive target for cancer treatment.In this study we collected 77 squamous cell carcinoma tissues and 18 matched adjacent normal tissues from the patients operated in our hospital. mTOR/4EBP1 expression and the relationship with pathology was detected by immunohistochemistry method. As to probe the role of mTOR and 4EBP1 in the occurrence and development of laryngeal squamous cell carcinoma,it may provide a new theoretical basis for treatment.Materials and Methods1. We Collected 77 squamous cell carcinoma tissues as experimental group and 18 matched adjacent normal tissues as comparison group from the patients (2008.8-2009.10) operated in our hospital. All of the patients in the study had not been treated with radiation or chemical therapy before the operation. All the clinical information was complete and the tissues were confirmed by pathological examination.2. The expression of mTOR,4EBP1 in the experimental group and comparison group was measured by immunohistochemistry SP method. The relativity between the groups was analyzed. 3. SPSS 13.0 statistical package was used for data analysis, the data was tested by X2 test and the correlation was analyzed by Spearman rank analysis. (P<0.05) was considered statistically significant.Results1. MTOR protein mainly express in the cytoplasm of squamous cell carcinoma. The positive expression rate was 54.5%(42/77) and positive expression rate was 22.2%(4/18) in adjacent normal tissues. The expression difference between the two groups was statistically significant (P<0.05).2.4EBP1 protein mainly expressed in the cytoplasm and a small quantity expressed in nucleus. In laryngeal squamous cell carcinoma the positive expression rate was 48.1%(37/77) and in adjacent normal tissues the positive expression rate was 11.1%(2/18). The expression difference between the two groups was statistically significant (P<0.05).3.In the experimental group, the positive expression rate of mTOR was 66.7% (36/54) with lymph node metastasis, and 26.1%(6/23) without lymph node metastasis. According to the pathology classification, the positive expression rate was 72.2%(26/36)in the middle, low differentiation group, and 39.0%(16/41)in the high differentiation group. The expression difference between the two groups was statistically significant (P<0.05).4. In the experimental group, the positive expression rate of 4EBP1 was 57.4% (31/54) with lymph node metastasis, and 26.1%(6/23) without lymph node metastasis. According to the pathology classification, the positive expression rate was 63.9%(23/36)in the middle, low differentiation group, and 34.1%(14/41)in the high differentiation group. The expression difference between the two groups was statistically significant (P<0.05). 5. the expression of mTOR and 4EBP1 in laryngeal squamous cell carcinoma was positively correlated (P< 0.05)Conclusion1.The highly expression of mTOR,4EBP1 signal transduction pathway in laryngeal squamous cell carcinoma may suggest that mTOR,4EBP1 play a role in the growth, proliferation and metastasis in laryngeal squamous cell carcinoma.2. The expression of mTOR and 4EBP1 signal transduction pathway in laryngeal squamous cell carcinoma was positively related. It suggest that mTOR and 4EBP1 may cooperate with each other during the occurrence and development process of laryngeal squamous cell carcinoma.