Significant relationship between the LAT1 expression pattern and chemoresistance in ovarian clear cell carcinoma

Virchows Arch. 2019 Jun;474(6):701-710. doi: 10.1007/s00428-019-02520-0. Epub 2019 Jan 13.

Abstract

L-type amino acid transporter 1 (LAT1) is a Na+-independent neutral amino acid transporter that plays a key role in cancer cell growth and survival. To determine the significance of LAT1 in prognosis and resistance to chemotherapy in ovarian carcinoma, we investigated the LAT1 expression in 245 ovarian carcinoma patients by immunohistochemistry using tissue microarray. High expression of LAT1 was detected in 85 (34.7%) patients. The ratio of high expression of LAT1 was significantly high in clear cell carcinoma and low in serous carcinoma compared to other histological types (P < 0.0001). High expression of LAT1 in ovarian carcinoma was associated with poorer prognosis as per log-rank test (P = 0.008). Cox's univariate and multivariate analysis revealed that high expression of LAT1 is an independent marker indicating poor prognosis (hazard ratio = 2.810, P < 0.0001) as well as the FIGO stage III/IV (vs. I/II) and suboptimal surgery. High LAT1 expression was also found to be associated with resistance to chemotherapy (P = 0.016) notably in clear cell carcinoma. In conclusion, we demonstrate that LAT1 is not only associated with poor prognosis of ovarian carcinoma, but also associated with chemoresistance in ovarian carcinoma.

Keywords: Chemotherapy; Immunohistochemistry; LAT1; Ovarian cancer; Transporter.

MeSH terms

  • Adenocarcinoma, Clear Cell / metabolism
  • Adenocarcinoma, Clear Cell / pathology*
  • Adult
  • Aged
  • Biomarkers, Tumor / metabolism*
  • Carcinoma, Squamous Cell / metabolism
  • Carcinoma, Squamous Cell / pathology*
  • Drug Resistance, Neoplasm / physiology
  • Female
  • Humans
  • Immunohistochemistry / methods
  • Large Neutral Amino Acid-Transporter 1 / metabolism*
  • Middle Aged
  • Neoplasm Staging / methods
  • Ovarian Neoplasms / diagnosis
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology*
  • Prognosis

Substances

  • Biomarkers, Tumor
  • Large Neutral Amino Acid-Transporter 1