Lack of correlation between P-glycoprotein and chemotherapy resistance in nasal NK/T-cell lymphomas

Gwi Eon Kim, Woo Ick Yang, Sang Wook Lee, Sun Young Rha, Hyun Cheol Chung, Joo Hang Kim, Jae Ho Cho, Chang Ok Suh, Nae Choon Yoo, Jae Kyung Roh, Jee Sook Hahn

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


Thirty patients with nasal natural killer (NK)/T-cell lymphoma, who underwent systemic chemotherapy with or without involved-field radiotherapy between 1993 and 1998, were retrospectively reviewed to determine the clinical significance of P-glycoprotein inummohistochemically identified in tumor specimens. Eighty percent of previously untreated patients expressed P-glycoprotein. According to P-glycoprotein immunoreactivity, all patients with nasal NK/T-cell lymphoma were divided into 2 groups; (a) P-glycoprotein-negative group (N = 6) and (b) P-glycoprotein-positive group (N = 24). There was no significant difference in clinical profiles between both groups. Regardless of the P-glycoprotein expressions, Epstein-Barr virus genomes were almost identically detected in patients of the 2 groups. Contrary to our expectations, however, P-glycoprotein expressions were not found to be a strong predictor of chemotherapy resistance. Although 2 (33%) of 6 P-glycoprotein-negative patients and 10 (42%) of the 24 P-glycoprotein-positive patients showed a favorable response to systemic chemotherapy, 4 (67%) of 6 P-glycoprotein-negative patients did not achieve complete response (CR) to chemotherapy, which led to an early death, whereas 4 (17%) of the 24 P-glycoprotein-positive patients achieved CR to chemotherapy despite positive P-glycoprotein immunoreactivity. Overall, there were no significant differences in either CR rate or the response rate of patients in the two groups. Overall 5-year actuarial survival and disease-free survival for all patients were 44% and 47%, respectively, but no differences in survival rates were observed between 2 groups. (5-year actuarial survival rate: 33% for the P-glycoprotein-negative, 50% for the P-glycoprotein-positive) (P = 0.7093, log-rank). On univariate and multivariate analyses, P-glycoprotein expressions by immunohistochemical study were not found to be an important prognostic factor. Given these observations, we conclude that the molecular mechanisms of resistance to chemotherapy in nasal NK/T-cell lymphoma patients are not entirely dependent on P-glycoprotein, and that other complex mechanisms of drug action and resistance may be likely to be involved.

Original languageEnglish
Pages (from-to)1857-1864
Number of pages8
JournalLeukemia and Lymphoma
Issue number9
Publication statusPublished - 2004 Sept

All Science Journal Classification (ASJC) codes

  • Hematology
  • Oncology
  • Cancer Research


Dive into the research topics of 'Lack of correlation between P-glycoprotein and chemotherapy resistance in nasal NK/T-cell lymphomas'. Together they form a unique fingerprint.

Cite this