Evaluation of glutathione metabolic genes on outcomes in advanced non-small cell lung cancer patients after initial treatment with platinum-based chemotherapy: an NCCTG-97-24-51 based study.
BACKGROUND
We evaluated the role of glutathione-related genotypes on overall survival, time to progression, adverse events, and quality of life (QOL) in stage IIIB/IV non-small cell lung cancer patients who were stable or responding from initial treatment with platinum-based chemotherapy and subsequently randomized to receive daily oral carboxyaminoimidazole or a placebo.


METHODS
Of the 186 total patients, 113 had initial treatment with platinum therapy and DNA samples of whom 46 also had QOL data. These samples were analyzed using six polymorphic DNA markers that encode five important enzymes in the glutathione metabolic pathway. Patient QOL was assessed using the Functional Assessment of Cancer Therapy-Lung and the UNISCALE QOL questionnaires. A clinically significant decline in QOL was defined as a 10% decrease from baseline to week-8. Multivariate analyses were used to evaluate the association of the genotypes on the four endpoints.


RESULTS
Patients carrying a GCLC 77 genotype had a worse overall survival (hazard ratio (HR) = 1.5, p = 0.05). Patients carrying the GPX1-CC genotype had a clinically significant decline in the UNISCALE (odds ratio (OR): 7.5; p = 0.04), total Functional Assessment of Cancer Therapy-Lung score (OR: 11.0; p = 0.04), physical (OR: 7.1; p = 0.03), functional (OR: 5.2; p = 0.04), and emotional well-being constructs (OR: 23.8; p = 0.01).


CONCLUSIONS
Genotypes of glutathione-related enzymes, especially GCLC, may be used as host factors in predicting patients' survival after platinum-based chemotherapy. GPX1 may be an inherited factor in predicting patients' QOL. Further investigation to define and measure the effects of these genes in chemotherapeutic regimens, drug toxicities, disease progression, and QOL are critical.
College of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA. yang.ping@mayo.edu
Ping
P
Yang
Sumithra J
SJ
Mandrekar
Shauna H
SH
Hillman
Katie L
KL
Allen Ziegler
Zhifu
Z
Sun
Jason A
JA
Wampfler
Julie M
JM
Cunningham
Jeff A
JA
Sloan
Alex A
AA
Adjei
Edith
E
Perez
James R
JR
Jett
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D016190:Carboplatin / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics / Q000401:mortality / Q000523:psychology; D002945:Cisplatin / Q000627:therapeutic use*; D005260:Female; D005838:Genotype; D005978:Glutathione / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000235:genetics; D051549:Glutathione S-Transferase pi / Q000235:genetics; D005982:Glutathione Transferase / Q000235:genetics; D006801:Humans; D016015:Logistic Models; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000401:mortality / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D016896:Treatment Outcome; D000094765:Glutathione Peroxidase GPX1
D000970:Antineoplastic Agents; D016190:Carboplatin; D005979:Glutathione Peroxidase; C413545:glutathione S-transferase T1; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; D005978:Glutathione; D002945:Cisplatin; D000094765:Glutathione Peroxidase GPX1; C000722067:GPX1 protein, human