Altered expression of miR-21 and PTEN in human laryngeal and hypopharyngeal squamous cell carcinomas.
OBJECTIVE
The purpose of this study was to examine the expression of mir-21 and phosphatase and tensin homologue (PTEN) in laryngeal squamous cell carcinomas (LSCCs) and hypopharyngeal squamous cell carcinomas (HSCCs), and assess correlations between the two as well as with clinical characteristics of patients.


METHODS
The expression of mir-21 in tumor and adjacent non-tumor tissues was investigated by real-time RT-PCR. Immunohistochemistry (IHC) was carried out to analyze PTEN protein levels.


RESULTS
Mir-21 was up-regulated in LSCCs and HSCCs compared to adjacent non-tumor tissues (P < 0.05), and the up-regulated expression of mir-21 was associated with clinical stage (P = 0.001), T classification (P = 0.007), pathologic differentiation (P = 0.025), and lymph node positivity (P = 0.002). In contrast, PTEN IHC staining was notably weaker in tumor tissues than in matched non-tumor tissues (P < 0.05), and the down-regulated expression of PTEN was correlated with tumor staging (P = 0.025), the extent of tumor (P = 0.017), and lymph node positivity (P = 0.040). Furthermore, the level of mir-21 was reversely correlated with PTEN expression (P = 0.006).


CONCLUSIONS
mir-21 and PTEN might play important roles in the progression of LSCC and HSCC, the two fcators demonstrating a negative correlation.
Department of Otolaryngology, Qilu Hospital, Shandong University, Jinan, China.
Jun
J
Liu
Da-Peng
DP
Lei
Tong
T
Jin
Xue-Ning
XN
Zhao
Guojun
G
Li
Xin-Liang
XL
Pan
D014408:Biomarkers, Tumor / Q000032:analysis; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D007822:Laryngeal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D051059:PTEN Phosphohydrolase / Q000378:metabolism*
D014408:Biomarkers, Tumor; C524940:MIRN21 microRNA, human; D035683:MicroRNAs; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human