title: Intratumoral localization and activity of 17β-hydroxysteroid dehydrogenase type 1 in non-small cell lung cancer: a potent prognostic factor.
abstract: BACKGROUND
  Estrogens were recently demonstrated to be synthesized in non-small cell lung carcinomas (NSCLCs) via aromatase activity and aromatase inhibitor (AI) did suppressed estrogen receptor (ER) positive NSCLC growth. However, other enzymes involved in intratumoral production and metabolism of estrogens, i.e. 17β-hydroxysteroid dehydrogenases (i.e. 17βHSD1 and 17βHSD2) and others have not been studied. Therefore, in this study, we examined the clinical/ biological significance of 17β-hydroxysteroid dehydrogenases in NSCLCs.
  
  
  METHODS
  Archival materials obtained from 103 NSCLC patients were immunohistochemically evaluated using anti-17βHSD1 and anti-17βHSD2 antibodies. The findings of immunohistochemistry were then correlated with intratumoral estrone (E1) and estradiol (E2) concentration, clinicopathological factors and overall survival of the patients. We further employed NSCLC cell lines, A549 and LK87 to study the functional significance of 17βHSD1, in vitro.
  
  
  RESULTS
  A higher 17βHSD1 immunoreactivity tended to be positively associated with aromatase (p=0.057) and tumor stage (p=0.055) whereas a higher 17βHSD2 immunoreactivity was positively associated with a squamous cell and adenosquamous cell carcinomas subtypes (p=0.031), tumor stage (p=0.004), T factor of TNM classification (p=0.010), maximum tumor diameter (p=0.002) and tended to be associated with N factor of TMN classification (p=0.065). A higher 17βHSD1 immunoreactivity was also significantly associated with lower intratumoral E1 concentration (p=0.040) and a higher intratumoral E2/E1 concentration ratio (p=0.028). On the other hand a higher 17βHSD2 immunoreactivity was significantly associated with higher intratumoral E1 concentration (p=0.035). Results of multivariate regression analysis demonstrated an increased 17βHSD1 immunoreactivity in tumor cells as an independent negative prognostic factor (HR= 2.83, p=0.007). E1 treatment in 17βHSD1 positive NSCLC cells, A549 and LK87, resulted in E2 production (p<0.0001) and enhanced cell proliferation, which was abrogated effectively by 17βHSD1 siRNA knockdown (p<0.0001). In addition, aromatase inhibitor treatment resulted in 17βHSD1 up regulation in both A549 and LK87 cells.
  
  
  CONCLUSIONS
  Results of our present study suggest that 17βHSD1 may be considered an important prognostic factor in NSCLC patients and targeting 17βHSD1 activity may further improve the clinical response in estrogen responsive NSCLC patients.
authors.affiliation: Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Mohit K
authors.initials: MK
authors.lastname: Verma
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Miki
authors.forename: Keiko
authors.initials: K
authors.lastname: Abe
authors.forename: Takashi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Niikawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Suzuki
authors.forename: Takashi
authors.initials: T
authors.lastname: Kondo
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sasano
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000378:metabolism; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000378:metabolism*; D045744:Cell Line, Tumor; D002853:Chromatography, Liquid; D004958:Estradiol / Q000032:analysis; D004970:Estrone / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D021241:Spectrometry, Mass, Electrospray Ionization; D016896:Treatment Outcome
chemical_list: D004970:Estrone; D004958:Estradiol; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase