J Pathol Transl Med.  2016 Mar;50(2):122-128. 10.4132/jptm.2015.10.31.

Prognostic Significance of Aquaporin 5 Expression in Non-small Cell Lung Cancer

• Jo YM
• Park TI
• Lee HY
• Jeong JY
• Lee WK

• KMID: 2211379
• DOI: http://doi.org/10.4132/jptm.2015.10.31

Abstract

BACKGROUND
Aquaporins are water channel proteins that play a major role in the movement of water in various human tissues. Recently, it has been found that aquaporins have influence in the carcinogenesis of human malignancies. We analyzed the prognostic impact of aquaporin 5 (AQP5) in non-small lung cancer (NSCLC).
METHODS
Seventy-six cases of NSCLC were studied, including 44 cases of adenocarcinoma (ADC) and 32 cases of squamous cell carcinoma (SQCC). Tissue microarray was constructed and immunohistochemical staining for AQP5 was performed.
RESULTS
AQP5 was positive in 59.2% of the total enrolled NSCLCs (63.7% in ADC and 53.1% in SQCC). The difference in expression of AQP5 according to the histologic grade of the tumor was significant (p<.047), but not in a serial order. When ADC and SQCC were separately evaluated, no significant difference was observed according to the histologic grade of the tumor (p=.076 in ADC and p=.631 in SQCC). No difference was observed between AQP5 expression and other demographic data and tumor characteristics. Disease-free survival (DFS) was higher in AQP5 negative cases than positive cases in ADC (p=.047), but no significance was found in SQCC (p=.068). We were unable to find a significance between AQP5 overexpression and overall survival in either ADC (p=.210) or SQCC (p=.533).
CONCLUSIONS
AQP5 expression is associated with DFS in ADC of the lung and tumor grade of NSCLC. The present study suggests that AQP5 can be a prognostic factor of NSCLC.

Keyword

Aquaporin 5; Carcinoma, non-small cell lung; Adenocarcinoma; Carcinoma, squamous cell

MeSH Terms

Adenocarcinoma
Aquaporin 5*
Aquaporins
Carcinogenesis
Carcinoma, Non-Small-Cell Lung*
Carcinoma, Squamous Cell
Disease-Free Survival
Humans
Lung
Lung Neoplasms
Water
Aquaporin 5
Aquaporins
Water

Figure

• 

  Fig. 1. Immunohistochemical staining with aquaporin 5. (A) No staining (0). (B) Weak, mild staining (1 +). (C) Moderate staining (2 +). (D) Strong staining (3 +).

• 

  Fig. 2. Overall survival (A) and disease-free survival (B) graphs with log-rank test in adenocarcinoma. Aquaporin 5 (AQP5) positive and negative cases are illustrated with bold dotted and solid lines, respectively. A 95% confidence interval (CI) is included in this graph and illustrated with fine dotted and solid lines. KM, Kaplan-Meier; AC, adenocarcinoma.

• 

  Fig. 3. Overall survival (A) and disease-free survival (B) graph with log-rank test in squamous cell carcinoma. Aquaporin 5 (AQP5) positive and negative cases are illustrated with bold dotted and solid lines, respectively. A 95% confidence interval (CI) is included in this graph and illustrated with fine dotted and solid lines. KM, Kaplan-Meier; SQ, squamous cell carcinoma.

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