Objective To explore the effect and significance of the TGF-β1 signaling system in laryngeal squamous cell carcinoma(LSCC). Methods The immunohistochemical method was used to detect expression of TGF-β1, TβRII, and Smad4 in 44 cases of LSCC and 10 cases of normal laryngeal mucosa. Correlation between the results and LSCC progress and metastasis was analyzed. Results The expression rate of TGF-β1 in the LSCC group was 68.2%, which was significantly different from the normal laryngeal mucosa group(30.0%, P<0.05), and the expression of TGF-β1 was associated with clinical stages and lymph node metastasis(P<0.05). The positive expression rate of TβRII and Smad-4 was 40.9%, 34.1% in the LSCC group and 80.0%, 80.0% in the normal laryngeal mucosa group(P<0.05). There was a negative correlation between TβRII and clinical stages (P<0.05), but no correlation between TβRII and lymph node metastasis（P>0.05）. There was a negative correlation between Smad4 and the clinical index(P<0.05), including pathological differentiation, clinical stage and lymph node metastasis. Conclusion There is a significant correlation between the abnormal TGFβ1/Smad4 signaling system and LSCC progress. Low expression of Smad4 may accelerate lymph node metastasis of LSCC.
