Sex difference in 5-year relative survival following percutaneous coronary intervention

Background

Sex-specific survival following percutaneous coronary intervention (PCI) varies among studies. This might be clarified using relative survival, which adjusts observed survival in relation to that seen in sex- and age-matched general population. We investigated sex-specific relative survival after PCI.

Methods

A total of 48,783 patients were enrolled in the year 2011 Korean nationwide PCI cohort. Primary outcome was all-cause death. Observed and relative survival at 5 years conditional on surviving 0 days, 30 days, 1 year, and 2 years were assessed. Sex-specific differences in cardiovascular risk factors were adjusted via age-group stratified propensity score matching.

Results

In the unadjusted analyses, 15,710 female patients had a higher frequency of cardiovascular risk factors compared with 33,073 male patients. Both observed survival (hazard ratio [HR]=1.28, 95% confidence interval [CI]=1.22–1.34) and relative survival (HR=1.21, 95% CI: 1.16–1.27) were worse in female compared with male (p<0.001, all). In analyses of propensity score-matched 14,454 pairs, female showed a higher observed survival (HR=0.78, 95% CI: 0.74–0.82) but a lower relative survival (HR=1.19, 95% CI: 1.13–1.26) compared with male (p<0.001, all). Neither observed nor relative survival differed between female of age≤50s and age-matched male, but they were lower in female of age≥60s than age-matched male. These findings were consistent in further analyses conditional on surviving 30 days, 1 year, and 2 years.

Conclusions

The 5-year relative survival of female aged≥60 years adjusted by clinical risk factors was lower than that of age-matched male, which mandates the need for the excessive risk reduction in older female undergoing PCI.

Funding Acknowledgement

Type of funding sources: None.

Hyperaemic and non-hyperaemic pressure indices of coronary stenosis severity in patients with chronic kidney disease

Background

Evidence regarding the use of pressure indices for the assessment of coronary stenoses in patients with chronic kidney disease (CKD) is scarce.

Methods

We assessed the relation between eGFR, FFR and resting Pd/Pa in 1147 consecutive patients (1316 vessels) included in the International Collaboration of Comprehensive Physiologic Assessment Study. We also compared FFR and Pd/Pa against a standardized cut-off of coronary flow reserve (CFR<2.0). Finally, we examined the occurrence of vessel-oriented composite outcome (VOCO: cardiac death, vessel-specific revascularization, vessel-specific myocardial infarction) across negative/positive results of both FFR and CFR in patients with and without CKD.

Results

FFR increases as renal function worsens (beta −10.5, 95% CI −20.0 to −11.03, p=0.030), a relation that was not seen with resting Pd/Pa (beta −6.14, 95% CI −19.9 to 6.78, p=0.351). Both indices had similar diagnostic accuracies for the detection of a CFR<2.0 in the presence of CKD (AUC 0.629 for FFR vs 0.663 for resting Pd/Pa, p=0.192). However, CKD patients showed a higher proportion of vessels with negative FFR but low CFR (24.5% vs 13.4%, p=0.015).

CFR decreased linearly with deteriorating eGFR, and this was mainly driven by higher resting coronary flow in CKD patients (p=0.026), while hyperaemic coronary flow remained similar (p=0.403). IMR did not change significantly with eGFR (beta −0.02, 95% −0.09 to 0.05, p=0.557).

The incidence of VOCO was higher in patients with CKD and FFR>0.80 when compared to non-CKD patients and FFR>0.80 (12.7% vs 6.90%, p=0.062). Prognosis was worse for those with CKD, negative FFR and CFR<2.0 (20.59% vs. 8.44% in non-CKD, p=0.038).

Conclusions

The assessment of a given coronary stenosis in patients with CKD with either FFR or resting Pd/Pa is equivalent when compared to underlying coronary flow. In CKD, impaired CFR is caused by a state of increased resting flow. The assessment of CFR on top of standard pressure wire examination significantly improves prognostic stratification in CKD patients.

Funding Acknowledgement

Type of funding sources: None.

Aspirin vs. Clopidogrel as a Chronic maintenance monotherapy after PCI in patients with high ischemic risk and high bleeding risk: Subgroup analysis of the HOST-EXAM trial

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

on behalf of the HOST-EXAM investigators

Background

The HOST-EXAM randomized clinical trial recently performed a comparison of clopidogrel monotherapy vs. aspirin monotherapy in patients requiring indefinite antiplatelet monotherapy after percutaneous coronary intervention (PCI). This study randomized 5,438 patients who maintained dual antiplatelet therapy without clinical events for 6–18 months after PCI with drug-eluting stents (DES) to receive a monotherapy agent of clopidogrel 75 mg once daily or aspirin 100 mg once daily for 24 months. During the 24-month follow-up, the primary outcome (a composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and Bleeding Academic Research Consortium (BARC) bleeding type 3 or greater) rate was significantly lower in the clopidogrel group (hazard ratio [HR] 0.73 [95% CI 0.59–0.90]; p = 0.0035). However, it is uncertain whether the beneficial effect of clopidogrel will be consistent in patients with high ischemic risk or those with high bleeding risk.

Methods

This is a post-hoc analysis of the HOST-EXAM trial. A high ischemic risk was defined as those who had at least 1 of the following procedural features: 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation PCI, total stent length >60 mm, or left main PCI. Patients with high bleeding risk were defined according to the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria. The co-primary outcome were thrombotic endpoints (a composite of cardiac death, non-fatal myocardial infarction, ischemic stroke, readmission due to acute coronary syndrome, and definite or probable stent thrombosis) and bleeding endpoints (BARC type ≥2 bleeding events) at 24-month follow-up.

Results

 Among the total population, 22.1% had high ischemic risk and 21.4% had high bleeding risk. Complex PCI was not associated with a higher risk of thrombotic endpoints, nor bleeding endpoints. For patients with a high bleeding risk, these patients had a higher risk of both thrombotic endpoints (HR 1.545, 95% CI 0.141-2.092, p = 0.005) and bleeding endpoints (HR 3.418, 95% CI 2.413-4.840, p < 0.001). The primary results focusing on the interaction between high ischemic risk, high bleeding and the antiplatelet regimen will be presented.

Conclusion

The current post-hoc analysis of the HOST-EXAM trial will evaluate the efficacy of clopidogrel monotherapy vs. aspirin monotherapy during the chronic maintenance period after PCI, in patients with high ischemic risk or those with high bleeding risk.

Bilirubin and Stroke Risk Using a Mendelian Randomization Design

BACKGROUND AND PURPOSE

Circulating bilirubin, a natural antioxidant, is associated with decreased risk of stroke. However, the nature of the relationship between the two remains unknown. We used a Mendelian randomization analysis to assess the causal effect of serum bilirubin on stroke risk in Koreans.

METHODS

The 14 single-nucleotide polymorphisms (SNPs) (<10^-7) including rs6742078 of uridine diphosphoglucuronyl-transferase were selected from genome-wide association study of bilirubin level in the KCPS-II (Korean Cancer Prevention Study-II) Biobank subcohort consisting of 4793 healthy Korean and 806 stroke cases. Weighted genetic risk score was calculated using 14 SNPs selected from the top SNPs.

RESULTS

Both rs6742078 (F statistics=138) and weighted genetic risk score with 14 SNPs (F statistics=187) were strongly associated with bilirubin levels. Simultaneously, serum bilirubin level was associated with decreased risk of stroke in an ordinary least-squares analysis. However, in 2-stage least-squares Mendelian randomization analysis, no causal relationship between serum bilirubin and stroke risk was found.

CONCLUSIONS

There is no evidence that bilirubin level is causally associated with risk of stroke in Koreans. Therefore, bilirubin level is not a risk determinant of stroke.

STAT1-mediated Bim expression promotes the apoptosis of retinal pericytes under high glucose conditions

Hyperglycemia impacts different vascular cell functions and promotes the development and progression of various vasculopathies including diabetic retinopathy. Although the increased rate of apoptosis in pericytes (PCs) has been linked to increased oxidative stress and activation of protein kinase C-δ (PKC-δ) and SHP-1 (Src homology region 2 domain-containing phosphatase-1) tyrosine phosphatase during diabetes, the detailed mechanisms require further elucidation. Here we show that the rate of apoptosis and expression of proapoptotic protein Bim were increased in the retinal PCs of diabetic Akita/+ mice and mouse retinal PCs cultured under high glucose conditions. Increased Bim expression in retinal PCs under high glucose conditions required the sustained activation of signal transducer and activator of transcription 1 (STAT1) through production of inflammatory cytokines. PCs cultured under high glucose conditions also exhibited increased oxidative stress and diminished migration. Inhibition of oxidative stress, PKC-δ or Rho-associated protein kinase I/II was sufficient to protect PCs against apoptosis under high glucose conditions. Furthermore, PCs deficient in Bim expression were protected from high glucose-mediated increased oxidative stress and apoptosis. However, only inhibition of PKC-δ lowered Bim levels. N-acetylcysteine did not affect STAT1 levels, suggesting that oxidative stress is downstream of Bim. PCs cultured under high glucose conditions disrupted capillary morphogenesis of retinal endothelial cells (ECs) in coculture experiments. In addition, conditioned medium prepared from PCs under high glucose conditions attenuated EC migration. Taken together, our results indicate that Bim has a pivotal role in the dysfunction of retinal PCs under high glucose conditions by increasing oxidative stress and death of PCs.

Lack of association of genetic variations of deoxycytidine kinase with toxicity or survival of non-small cell lung cancer patients treated with gemcitabine plus cisplatin

e13065

Background: To determine whether tagging polymorphisms (tSNPs) of deoxycytidine kinase (DCK) have an effect on toxicity or prognosis in patients with non–small-cell lung cancer (NSCLC) treated with gemcitabine plus cisplatin. Methods: Three tSNPs (−201 C>T, rs2306744; IVS2+9846 G>A, rs12648166; IVS6+1392 T>C, rs4694362) were chosen using two databases, the international HapMap Project and Japanese Single-Nucleotide Polymorphisms. Genotyping was performed using the Genome Lab SNPstream Genotyping System and SNaPShot assay kit. We evaluated the associations of the tSNPs with hematologic toxicity or overall survival of 139 NSCLC patients at stages IIIA/IIIB (59) and IV (80). Results: The median survival time of the patients was 11.9 months. Hematologic toxicity such as neutropenia, thrombocytopenia and anemia were not different by the three tSNPs or haplotypes (CGT, CAT and CAC) of DCK. The genetic variations did not affect on survival of the patients (log-rank P: 0.248 for −201 C>T, 0.571 for IVS2+9846 G>A, 0.686 for IVS6+1392 T>C, 0,556 for CGT, 0.453 for CAT and 0.845 for CAC). In Cox model, these tSNPs and haplotypes did not reveal prognostic relevance (aHR and 95%CI: 0.954 and 0.611 to 1.489 for −201 C>T; 1.193 and 0.719 to 1.979 for IVS2+9846 G>A; 1.072 and 0.674 to 1.706 for IVS6+1392 T>C, 0,668 and 0.205 to 2.175 for CGT, 1.043 and 0.713 to 1.525 for CAT and1.043 and 0.701 to 1.550 for CAC). Conclusions: This is the first study to focus on the association of tSNPs and their haplotypes of DCK with toxicity and survival in NSCLC patients. This suggests that genetic variations of DCK have no effect on the outcomes in the patients treated with gemcitabine-based chemotherapy.

Genome-wide association study of survival in small cell lung cancer patients treated with irinotecan and cisplatin chemotherapy

7089

Background: The prognosis of patients with extensive-disease small-cell lung cancer (ED-SCLC) remains poor. Despite a high initial response rate to chemotherapy, most patients die from rapid recurrence. We conducted a genome-wide analysis study (GWAS) to examine whether germline genetic variations are prognostic factors in ED-SCLC patients treated with irinotecan and cisplatin (IP) chemotherapy. Methods: We prospectively collected blood samples from 139 patients who participated in two phase II studies of IP chemotherapy as first-line therapy and conducted a GWAS using overall survival (OS) as the endpoint. Germline DNA was genotyped using the Affymetrix 5.0 or 6.0 array sets. Associations between OS and single nucleotide polymorphisms (SNPs) were investigated using multivariate Cox regression analysis. Adjustments for age, performance status (PS) and gender were made. We selected most promising SNPs with p<1×10−6 in the GWAS allelic association analyses. Results: A total of 426,019 SNPs were genotyped and 343,530 SNPs passed quality control (HWE, p<10-7, minor allele frequency>1%). We found 7 SNPs showing a significant association with OS. Patients harboring rs16950650 CT, rs7186128 AG or GG, rs17574269 AG, rs8020368 CC, rs4655567 CC, rs2166219 TT and rs2018683 TT genotypes showed shorter OS compared to patients with control alleles. Hazards ratios of death for each risk variants were 30.2 (95% CI, 8.3-109.0, p=2.1X10-7), 2.5 (95% CI, 1.7-3.5, p=3.8X10-7), 7.6 (95% CI, 3.4-16.6, p=4.5X10-7), 3.4 (95% CI, 2.1-5.5, p=3.5X10-7), 4.9 (95% CI, 2.7-9.0, p=3.1X10-7), 5.8 (95% CI, 2.9-11.7, p=8.4X10-7) and 7.8 (95% CI, 3.4-17.7, p=8.0X10-7), respectively. Among these SNPs, rs4655567, rs8020368, rs2018683 and rs17574269 were significantly associated with a refractory relapse. In multivariate logistic analysis including age, gender and PS, rs8020368 CC genotype showed higher risk of refractory relapse than patients with TT or TC genotype (HR=14.9 [95% CI, 1.9-114.8], p=0.010). Conclusions: This exploratory GWAS identified several candidate SNPs that might predictive for the outcome of patients with ED-SCLC receiving IP chemotherapy.

Abstract 1866: Genome-wide association study for irinotecan-related severe toxicities in patients with advanced non-small cell lung cancer

Purpose: We performed a case-control genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with severe diarrhea and neutropenia in patients treated with irinotecan for advanced non-small cell lung cancer (NSCLC). Patients and Methods: We performed a case-control GWAS using the Affymetrix 5.0 array set in 103 patients enrolled in two phase II studies of with irinotecan and cisplatin. A subsequent replication study was conducted to validate major GWAS findings in an independent series of 146 patients enrolled in another phase II study of irinotecan-based chemotherapy. Cases were defined as patients with grade 3 diarrhea (G3D) or grade 4 neutropenia (G4N) according to the National Cancer institute's Common Terminology Criteria for adverse events v3.0. Results: The GWAS included 11 G3D (control 90) and 24 G4N (control 77). The replication set included 13 G3D (control 133) and 21 G4N (control 125). GWAS identified 49 and 32 SNPs putatively associated with G3D and G4N, respectively. In the replication series, SNPs, rs1517114 (C8orf34), rs1661167 (FLJ41856), and rs2745761 (PLCB1) were confirmed for G3D, and rs11128347 (PDZRN3), rs11979430 and rs7779029 (SEMAC3) were confirmed for G4N. Conclusion: This GWAS screen along with subsequent validation indentified novels SNPs associated with irinotecan-related severe toxicities.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1866. doi:1538-7445.AM2012-1866

Genome-wide association analysis and replication of coronary artery disease in South Korea suggests a causal variant common to diverse populations

BACKGROUND

Recent genome-wide association (GWA) studies have identified and replicated several genetic loci associated with the risk of development of coronary artery disease (CAD) in samples from populations of Caucasian and Asian descent. However, only chromosome 9p21 has been confirmed as a major susceptibility locus conferring risk for development of CAD across multiple ethnic groups. The authors aimed to find evidence of further similarities and differences in genetic risk of CAD between Korean and other populations.

METHODS

The authors performed a GWA study comprising 230 cases and 290 controls from a Korean population typed on 490 032 single nucleotide polymorphisms (SNPs). A total of 3148 SNPs were taken forward for genotyping in a subsequent replication study using an independent sample of 1172 cases and 1087 controls from the same population.

RESULTS

The association previously observed on chromosome 9p21 was independently replicated (p=3.08e-07). Within this region, the same risk haplotype was observed in samples from both Korea and of Western European descent, suggesting that the causal mutation carried on this background occurred on a single ancestral allele. Other than 9p21, the authors were unable to replicate any of the previously reported signals for association with CAD. Furthermore, no evidence of association was found at chromosome 1q41 for risk of myocardial infarction, previously identified as conferring risk in a Japanese population.

CONCLUSION

A common causal variant is likely to be responsible for risk of CAD in Korean and Western European populations at chromosome 9p21.3. Further investigations are required to confirm non-replication of any other cross-race genetic risk factors.

HLA-DPB1 and DPB2 are genetic loci for systemic sclerosis: a genome-wide association study in Koreans with replication in North Americans

OBJECTIVE

To identify systemic sclerosis (SSc) susceptibility loci via a genome-wide association study.

METHODS

A genome-wide association study was performed in 137 patients with SSc and 564 controls from Korea using the Affymetrix Human SNP Array 5.0. After fine-mapping studies, the results were replicated in 1,107 SSc patients and 2,747 controls from a US Caucasian population.

RESULTS

The single-nucleotide polymorphisms (SNPs) (rs3128930, rs7763822, rs7764491, rs3117230, and rs3128965) of HLA-DPB1 and DPB2 on chromosome 6 formed a distinctive peak with log P values for association with SSc susceptibility (P=8.16x10(-13)). Subtyping analysis of HLA-DPB1 showed that DPB1*1301 (P=7.61x10(-8)) and DPB1*0901 (P=2.55x10(-5)) were the subtypes most susceptible to SSc in Korean subjects. In US Caucasians, 2 pairs of SNPs, rs7763822/rs7764491 and rs3117230/rs3128965, showed strong association with SSc patients who had either circulating anti-DNA topoisomerase I (P=7.58x10(-17)/4.84x10(-16)) or anticentromere autoantibodies (P=1.12x10(-3)/3.2x10(-5)), respectively.

CONCLUSION

The results of our genome-wide association study in Korean subjects indicate that the region of HLA-DPB1 and DPB2 contains the loci most susceptible to SSc in a Korean population. The confirmatory studies in US Caucasians indicate that specific SNPs of HLA-DPB1 and/or DPB2 are strongly associated with US Caucasian patients with SSc who are positive for anti-DNA topoisomerase I or anticentromere autoantibodies.

Association of single nucleotide polymorphisms in PIM-1 gene with the risk of Korean lung cancer

PURPOSE

The expression of the PIM-1 gene, which is a proto-oncogene that encodes a serine/threonine kinase, is associated with multiple cellular functions such as proliferation, differentiation, apoptosis and tumorigenesis. In particular, several studies have reported that the PIM-1 gene is associated with the development of lymphoma, leukemia and prostate cancer. Therefore, this study was conducted to evaluate the association between the single nucleotide polymorphisms in the PIM-1 gene and the risk of lung cancer occurrence in the Korean population.

MATERIALS AND METHODS

To evaluate the role of the PIM-1 gene in the development of lung cancer, the genotypes of the PIM-1 gene were determined in 408 lung cancer patients and 410 normal subjects.

RESULTS

We found that the T-C-T-C haplotypes of the PIM-1 gene (-1196 T>C, IVS4 +55 T>C, IVS4 +1416 T>A and +3684 C>A) were associated with an increased risk of lung cancer [adjusted odds ratio (aOR): 3.98; 95% CI: 1.24 approximately 12.75, p-value: 0.020]. In particular, these haplotypes showed an increased risk of lung cancer in males (aOR: 5.67; 95% CI: 1.32~24.30, p-value: 0.019) and smokers (aOR: 7.82; 95% CI: 1.75 approximately 34.98, p-value: 0.007).

CONCLUSIONS

The present results suggest that the T-C-T-C haplotype of the PIM-1 gene could influence the risk of developing smoking-related lung cancer in the Korean population. Additional functional studies with an larger sample sized analysis are warranted to reconfirm our findings.

Genotypes and haplotypes of beta2-adrenergic receptor and parameters of the metabolic syndrome in Korean adolescents

We investigated the association between single nucleotide polymorphisms (SNPs) and haplotype of the beta(2)-adrenergic receptor (ADRB2) gene and parameters of the metabolic syndrome in Korean adolescents. Body mass index, waist circumference, blood pressure, fasting glucose, triglycerides and high-density lipoprotein (HDL) cholesterol, free fatty acid and insulin, and homeostasis model assessment (HOMA) score were measured in 134 volunteer adolescents (69 male and 65 female). All subjects were genotyped for 5 SNPs: A-->G rs1042713 (Arg16Gly), C-->G rs1042714 (Gln27Glu), G-->A rs1042717 (Leu84Leu), C-->A rs1042718 (Arg175Arg), and G-->C rs1042719 (Gly351Gly). After adjustment for age and sex, we found that the rs1042717 SNP was associated with higher body weight, fasting insulin, and HOMA score. The rs1042714 SNP was associated with higher body fat, waist circumference, and free fatty acids; and the rs1042719 SNP was associated with higher diastolic blood pressure. The C-A-A-C haplotype at SNPs rs1042714, rs1042717, rs1042718, and rs1042719 was associated with higher body weight, fasting insulin, and HOMA score; the G-G-C-G was associated with higher body fat and waist circumference; the C-G-C-G was associated with lower HDL cholesterol; and the C-G-C-C was associated with lower body weight, lower waist circumference, and higher HDL cholesterol. In conclusion, these findings suggest that the genotypes and haplotypes of ADRB2 may influence parameters of the metabolic syndrome in Korean adolescents.

Putative association of the single nucleotide polymorphisms in RASSF1A promoter with Korean lung cancer

SUMMARY

The RASSF1 gene, a putative tumor suppressor gene located on human chromosome 3p21, has attracted a great deal of attention because of frequent allelic loss and gene silencing via promoter hypermethylation in a variety of human malignancies. To evaluate the role of RASSF1A gene in lung cancer risk, genotypes of the RASSF1A promoter region (-710 C>T and -392T>C) were determined in 410 lung cancer patients and 410 normal subjects. Furthermore, to examine potential effects of the common haplotypes (C-C, T-T and C-T haplotypes) on RASSF1A transcription, luciferase reporter assays were performed in H2009 and H358 non-small cell lung cancer (NSCLC) cell lines. We found that ht2 C-T haplotype was associated with susceptibility to the risk of lung cancer in dominant (odds ratio (OR): 0.69; 95% CI: 0.46-0.99) model. In particular, we found that C-T haplotype showed a decreased risk of lung cancer in males (codominant OR: 0.59; 95% CI: 0.38-0.93 and dominant OR: 0.58; 95% CI: 0.35-0.96) and in smokers (codominant OR: 0.58; 95% CI: 0.36-0.93 and dominant OR: 0.56; 95% CI: 0.33-0.96). Interestingly, C-T haplotype induced transcriptional activity by 50-60% compared with other haplotypes in NSCLC cell lines. These results suggest that RASSF1A promoter polymorphisms affect RASSF1A expression, further contributing to the genetic susceptibility to lung cancer.

Influence of the organic anion-transporting polypeptide 1B1 (OATP1B1) polymorphisms on irinotecan-pharmacokinetics and clinical outcome of patients with advanced non-small cell lung cancer

To investigate whether the OATP1B1 polymorphisms affect irinotecan-pharmacokinetics and subsequent toxicity and tumor response of patients with advanced NSCLC. A total of 81 Korean NSCLC patients enrolled in a phase II study of irinotecan and cisplatin chemotherapy were genotyped for OATP1B1 -11187G>A, 388A>G and 521T>C variants. The 521TC or CC and -11187AA genotypes were associated with higher AUC(SN-38) (p=0.016 and 0.030, respectively). When haplotypes were assigned, patients with *15 haplotype showed significantly higher AUC(SN-38) than *1a or *1b haplotypes (p=0.006). Grade 4 neutropenia was associated with the 521TC or CC genotypes, whereas, grade 3 diarrhea was associated with 388GG genotype (p=0.046). Of the 81 patients enrolled, 77 were assessable for response and 36 (47%) patients achieved partial responses (PR). However, no statistical significance was observed between genotype and response. These findings suggest that OATP1B1 variants are involved in SN-38 disposition and highly predictive for severe toxicity of NSCLC patients treated with irinotecan-based chemotherapy.

Associations of ABCB1, ABCC2, and ABCG2 polymorphisms with irinotecan-pharmacokinetics and clinical outcome in patients with advanced non-small cell lung cancer

BACKGROUND

The authors investigated whether ABCB1, ABCC2, and ABCG2 genetic polymorphisms affect pharmacokinetics (PK) of irinotecan and treatment outcome of patients with advanced nonsmall cell lung cancer (NSCLC).

METHODS

Blood samples from 107 NSCLC patients treated with irinotecan and cisplatin chemotherapy were used for genotyping ABCB1 (1236C > T, 2677G > T/A, 3435C > T), ABCC2 (-24C > T, 1249G > A, 3972C > T), and ABCG2 (34G > A, 421C > A) polymorphisms. Genotypes were correlated with irinotecan-PK, toxicity, tumor response, and survival.

RESULTS

Among 8 polymorphisms, 3435TT and 2677TT were associated with AUC(SN-38G) and CL(SN-38G). When haplotypes are assigned, 2677TT/3435TT carriers showed significantly lower AUC(SN-38G) (P = .006), whereas 2677GG/3435CC carriers showed significantly higher AUC(SN-38) (P = .039). These findings suggest that 2677TT and 3435TT variants are associated with higher efflux activity. In toxicity, the 2677G/T or A was associated with grade 4 neutropenia. The 2677GG carriers showed significantly lower absolute neutrophil count during the 1(st) cycle (P = .012) as well as entire course of chemotherapy (P = .042). The 3435TT was associated with higher frequency of grade 3 diarrhea (P = .047). In tumor response, ABCC2 -24TT and 3972TT genotypes were associated with higher response rates (P = .031 and P = .048, [corrected] respectively) and longer progression-free survival (P = .010 and P = .019, [corrected] respectively), which was sustained in haplotype analysis.

CONCLUSIONS

Specific polymorphisms of ABCB1 and ABCC2 can influence disposition and tumor response to irinotecan by regulating transporter activity. These findings may help to individualize irinotecan-based chemotherapy in patients with advanced NSCLC.

Comprehensive analysis of UGT1A polymorphisms predictive for pharmacokinetics and treatment outcome in patients with non-small-cell lung cancer treated with irinotecan and cisplatin

PURPOSE

To determine whether uridine diphosphate-glucuronosyltransferase 1A1, UGT1A7, and UGT1A9 polymorphisms affect the pharmacokinetics (PK) of irinotecan and treatment outcome of Korean patients with advanced non-small-cell lung cancer (NSCLC).

METHODS

Eighty-one patients with advanced NSCLC were treated with irinotecan (80 mg/m2) on day 1 and 8 and cisplatin (60 mg/m2) on day 1 intravenously of each 3-week cycle. Genomic DNA was extracted from peripheral blood and genotyped using direct sequencing. We analyzed the association of UGT1A genotypes with irinotecan PK and clinical outcomes. All statistical tests were two-sided.

RESULTS

In genotype-PK association analysis, UGT1A1*6/*6 (n = 6), UGT1A7*3/*3 (n = 6), and UGT1A9-118(dT)9/9 (n = 11) were associated with significantly lower area under the time-concentration curve (AUC) SN-38G to SN-38 (AUC(SN-38G)/AUC(SN-38)) ratio (P = .002, P = .009, and P = .001, respectively). In linkage disequilibrium analysis, the UGT1A7 variants were highly linked with the UGT1A1*6 (D' = 0.85, r2 = 0.63) and UGT1A9*22 (D' = 0.95, r2 = 0.88), which was substantiated in haplotype analysis. Patients with UGT1A1*6/*6 had lower tumor response and higher incidence of severe neutropenia. UGT1A9-118(dT)9/9 also showed a trend for high incidence of severe diarrhea, but not tumor response. In survival analysis, patients with UGT1A1*6/*6 had significantly shorter progression-free survival (P = .001) and overall survival (P = .017).

CONCLUSION

These findings suggest that UGT1A1*6 and UGT1A9*22 genotypes may be important for SN-38 glucuronidation and associate with irinotecan-related severe toxicity. Specifically, UGT1A1*6 might be useful for predicting tumor response and survival outcome of Korean patients with NSCLC treated with irinotecan-based chemotherapy.

Positive regulation of hepatic carnitine palmitoyl transferase 1A (CPT1A) activities by soy isoflavones and L-carnitine

BACKGROUND

Genistein increases CPT1A, a rate-limiting enzyme in the beta-oxidation pathway, enzyme activity by increasing CPT1A transcription in HepG2 cells and, consequently, suppresses high fat induced obesity in C57BL/6J mice. Genistein and daidzein are the most abundant isoflavones in soy.

AIM OF STUDY

To investigate the effect of co-treatment of genistein and L-carnitine on CPT1A enzyme activity and to determine whether daidzein also increases CPT1A activity and to establish a cell line that can be used to screen chemicals to regulate CPT1A transcription.

METHODS

The enzyme activities of CPT1A were determined after HepG2 cells were incubated with 10 microM genistein or 10 microM daidzein or 1 mM L-carnitine or in combination with 10 microM genistein and 1 mM L-carnitine or in combination with 10 microM daidzein and 1 mM L-carnitine. The mRNA expression levels of CPT1A were determined by real time PCR method after HepG2 cells were incubated with 10 microM genistein or 10 microM daidzein. A suggested CPT1A promoter region was cloned from human genomic DNA and the CPT1A promoter-luciferase reporter gene construct was made, and the promoter-reporter gene construct was transfected into human hepatoma cell line Huh7.

RESULTS

The enzyme activity of CPT1A was at least 2.3- fold higher in L-carnitine and genistein co-treated HepG2 cells than either single-agent treated cells. Daidzein also significantly increased the mRNA expression of CPT1A as well as the enzyme activity of CPT1A. A stable Huh7 cell line, which was selected after Huh7 cells were transfected with CPT1A promoter luciferase reporter gene construct, was characterized by confirming that luciferase activity of the cell line can be regulated by genistein and daidzein as well as clofibrate, a well-known CPT1A mRNA up-regulating drug.

CONCLUSIONS

Genistein and daidzein can up-regulate CPT1A enzyme activity through up-regulation of CPT1A transcription. Co-treatment of L-carnitine and genistein additively increases CPT1A enzyme activity in HepG2 cells. A stable Huh7 cell line transfected with the CPT1A promoter luciferase reporter gene was established and characterized.

Transjugular intrahepatic portosystemic shunt placement in the setting of polycystic liver disease: questioning the contraindication

Although polycystic liver disease has long been listed as a contraindication to transjugular intrahepatic portosystemic shunt (TIPS) creation, two cases of TIPS placement in that particular clinical setting have been reported. Another case is reported in this article and the clinical course over 21 months of follow-up is examined. The discussion reviews the mechanics of TIPS creation in a polycystic liver and the vague premise of the polycystic liver as a contraindication to TIPS.

Effect of weight control on hepatic abnormalities in obese patients with fatty liver

This study was aimed at finding out whether weight reduction alone can improve liver function in obese patients with fatty liver. We did a longitudinal, clinical intervention study on weight reduction by behavior modification, diet and exercise. The study subjects were 25 patients referred to an obesity clinic in whom obesity is the sole factor causing abnormal liver function and fatty liver. Patients were weighed about one year later. We compared the degree of improvement in hepatic function between Group I that showed weight reduction and Group II that showed no-weight reduction. Group I (13) showed dramatic improvement in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, nearly all down to within normal levels. AST showed statistically significant improvement from 74 +/- 36 IU/l to 25 +/- 7 IU/l. ALT also showed statistically significant improvement from 109 +/- 67 IU/l to 30 +/- 14 IU/l. Group II (12) showed higher AST and ALT levels on follow-up visit than initial visit. AST showed statistically significant elevation from 43 +/- 11 IU/l to 59 +/- 23 IU/l. ALT also showed statistically significant elevation from 64 +/- 21 IU/l to 97 +/- 33 IU/l. If we can rule the other causes of hepatic abnormalities in obese patients with fatty liver, we suggest these patients would benefit by weight reduction.