Baek-Yeol Ryoo

Epithelial to mesenchymal transition derived from repeated exposure to gefitinib determines the sensitivity to EGFR inhibitors in A549, a non-small cell lung cancer cell line

Epithelial to mesenchymal transition (EMT) has been reported to be related with reduced sensitivity to EGFR tyrosine kinase (EGFR-TK) inhibitors. We performed this study to investigate whether this phenomenon would play a role in acquired resistance to gefitinib. In this study, we established a gefitinib-resistant subline (A549/GR), which was derived from the parental A549 cell line by chronic, repeated exposure to gefitinib. Compared with the A549 cells, the A549/GR cells were approximately 7.7-fold more resistant to gefitinib and they showed the cross-resistance against other EGFR-TK inhibitors, including CL-387,758, erlotinib and ZD6478. Phenotypic changes such as a spindle-cell shape and increased pseudopodia formation suggesting EMT was present in the A549/GR cells. These changes were accompanied by a decrease of E-cadherin and an increase of vimentin, which is a mesenchymal marker. In addition, the ability of invasion and migration was increased in the A549/GR cells. TGF-beta1 treatment for 72 h also induced EMT in the A549 cells and this transition led to resistance to gefitinib. Conversely, this was reversed through the removal of TGF-beta1. In conclusion, induction of EMT may contribute to the decreased efficacy of therapy in primary and acquired resistance to gefitinib.

Clinical heterogeneity of extranodal NK/T-cell lymphoma, nasal type: a national survey of the Korean Cancer Study Group

BACKGROUND This national survey was undertaken to propose the classification of extranodal natural killer (NK)/T-cell lymphoma (NTCL) subtypes and to clarify a clinical heterogeneity. PATIENTS AND METHODS Two hundred and eighty patients newly diagnosed as NTCL were enrolled from 22 Korean medical centers. Two subsets were compared: one involving the upper aerodigestive tract (UAT) and another involving the non-upper aerodigestive tract (NUAT) region, which comprises the skin, gastrointestinal tract, and liver or soft tissues. Clinical prognostic factors, survival outcomes, and independent predictors for survival were compared between each subset. RESULTS NUAT-NTCL (59 patients) had significantly higher proportions of disseminated disease, aggressive biologic features, and unfavorable host reactions compared with UAT-NTCL (221 patients). NUAT-NTCL had shortened 5-year overall survival (OS) (22% versus 41%, P = 0.001). Ann Arbor staging, the International Prognostic Index, and the NTCL prognostic index failed to predict the OS of NUAT-NTCL, but did predict the OS in UAT-NTCL. Independent predictors for OS by multivariate analyses differed between each subset. In the NUAT subset, extranodal sites and regional nodes predicted the OS, while Ann Arbor staging, age, performance status, and lactate dehydrogenase level predicted the OS in the UAT subset. CONCLUSION NUAT-NTCL may represent a distinctive disease entity in terms of clinical factors, independent predictors, and survival outcomes.

Autologous Hematopoietic Stem Cell Transplantation in Extranodal Natural Killer/T Cell Lymphoma: A Multinational, Multicenter, Matched Controlled Study

Extranodal natural killer (NK)/T cell lymphoma, nasal type, is a recently recognized distinct entity and the most common type of non-B cell extranodal lymphoma in Asia. This retrospective analysis studied the potential survival benefits of hematopoeitic stem cell transplantation (HSCT) compared with a historical control group. A total of 47 patients from 3 previously published series of HSCT were matched according to NK/T cell lymphoma International Prognostic Index (NKIPI) risk groups and disease status at transplantation with 107 patients from a historical control group for analysis. After a median follow-up of 116.5 months, the median survival time was not determined for the HSCT group, but it was 43.5 months for the control group (95% confidence interval [CI] = 6.7 to 80.3 months; P = .127, log-rank test). In patients who were in complete remission (CR) at the time of HSCT or at surveillance after remission, disease-specific survival rates were significantly higher in the HSCT group compared with the control group (disease-specific 5-year survival rate, 87.3% for HSCT vs 67.8% for non-HSCT; P = .027). In contrast, in subgroup analysis on non-CR patients at the time of HSCT or non-HSCT treatment, disease-specific survival rates were not significantly prolonged in the HSCT group compared with the control group (1-year survival rate, 66.7% for HSCT vs 28.6% for non-HSCT; P = .141). The impact of HSCT on the survival of all patients was significantly retained at the multivariate level with a 2.1-fold (95% CI =1.2- to 3.7-fold) reduced risk of death (P = .006). HSCT seems to confer a survival benefit in patients who attained CR on postremission consolidation therapy. These findings suggest that, in particular, patients in CR with high NKIPI risk scores at diagnosis should receive full consideration for HSCT.

Resumption of imatinib to control metastatic or unresectable gastrointestinal stromal tumours after failure of imatinib and sunitinib (RIGHT): a randomised, placebo-controlled, phase 3 trial

BACKGROUND Few treatment options remain for patients with metastatic or unresectable gastrointestinal stromal tumours (GIST) after objective progression on approved tyrosine-kinase inhibitors. We aimed to assess efficacy of imatinib rechallenge in these patients. METHODS In our prospective, randomised, double-blind trial, we enrolled adults (≥18 years) who had previously benefited from first-line imatinib (initial response or stable disease for ≥6 months) but whose metastatic or unresectable GIST had progressed on at least imatinib and sunitinib. We randomly allocated participants in a 1:1 ratio, with a centralised computer-generated allocation procedure (random permuted blocks of two, four, and six) and stratified by previous treatment and Eastern Cooperative Oncology Group performance status, to receive best supportive care with imatinib 400 mg per day or matched placebo. Crossover to open-label imatinib was allowed after investigator-adjudicated disease progression. The primary endpoint was progression-free survival (PFS), as determined by a masked external radiological review. All analyses were done for all patients who received at least one dose of study drug. FINDINGS Between July 20, 2010, and Jan 17, 2013, we randomly allocated 41 patients to the imatinib group and 40 patients to the placebo group. After a median follow-up of 5·2 months (IQR 3·4-9·4), median PFS was 1·8 months (95% CI 1·7-3·6) with imatinib compared with 0·9 months (0·9-1·7) with placebo (hazard ratio for progression or death 0·46, 95% CI 0·27-0·78; p=0·005). 37 (93%) patients in the placebo group crossed over to open-label imatinib after progression. The most common grade 3 or worse adverse events were anaemia (12 [29%] of 41 patients in the imatinib group vs three [8%] of 40 in the placebo group), fatigue (four [10%] vs none), and hyperbilirubinaemia (three [7%] vs one [3%]). INTERPRETATION In patients with GIST that is refractory to treatment with all standard tyrosine-kinase inhibitors, the disease continues to harbour many clones that are sensitive to kinase inhibitors. Continued kinase suppression might slow, although not halt, disease progression.

Phase I study of proteasome inhibitor bortezomib plus CHOP in patients with advanced, aggressive T-cell or NK/T-cell lymphoma

The aim of the study was to determine the maximum tolerated dose (MTD) and safety of the combination of bortezomib and cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) as first-line therapy in advanced, aggressive T-cell lymphoma. Patients received increasing doses of bortezomib on days 1 and 8 (weekly schedule, 1.0, 1.3, and 1.6 mg/m(2)/dose) in addition to 750 mg/m(2) cyclophosphamide, 50 mg/m(2) doxorubicin, 1.4 mg/m(2) vincristine on day 1 and 100 mg/day prednisolone on days 1 to 5, every 3 weeks. Six cycles of therapy administered every 21 days were planned. Thirteen patients, who had stage III/IV chemonaive aggressive T-cell lymphoma, received a total of 55 cycles of treatment. One patient experienced hematologic dose-limiting toxicity (grade 4 neutropenia associated with febrile episode) at the 1.0 mg/m(2)/dose of bortezomib. There was no dose-limiting non-hematologic toxicity. The MTD was not reached at 1.6 mg/m(2) dose level of bortezomib. The overall complete remission rate in all patients was 61.5% (95% confidence interval = 31.6-86.1). Bortezomib can be safely combined with CHOP chemotherapy and constitutes an active regimen in advanced-stage, aggressive T-cell lymphoma patients. The recommended dose for subsequent phase II studies of bortezomib plus CHOP is 1.6 mg/m(2)/dose of bortezomib on days 1 and 8 every 3 weeks as first-line treatment.

Cross-Sectional Study of Imatinib Plasma Trough Levels in Patients With Advanced Gastrointestinal Stromal Tumors: Impact of Gastrointestinal Resection on Exposure to Imatinib

PURPOSE Imatinib plasma trough levels (C(min)) have been reported to correlate with treatment outcomes in patients with gastrointestinal stromal tumors (GISTs). We therefore have evaluated the correlation between imatinib C(min) and the clinical characteristics of patients with GIST. PATIENTS AND METHODS Steady-state imatinib C(min) in 107 patients with GIST who were taking imatinib 300 to 800 mg/d was measured. RESULTS In patients treated with imatinib 400 (n = 92), 300 (n = 7), 600 (n = 2), or 800 (n = 11) mg/d, imatinib C(min) was 1,305 +/- 633 ng/mL, 1,452 +/- 830 ng/mL, 1,698 +/- 725 ng/mL, and 3,330 +/- 1,592 ng/mL, respectively. Of the 92 patients treated with 400 mg/d imatinib, 59 patients (63%) were men; the median age was 55 years (range, 28 to 76 years), and the median duration of imatinib use before sampling was 8.8 months (range, 0.5 to 67.6 months). The mean inter- and intrapatient variability rates were 44.7% and 26.5%, respectively. In univariate analyses, high C(min) was correlated with advanced age (P = .02), low creatinine clearance (P = .001), low hemoglobin (P = .03), and low albumin (P < .001) concentrations. Imatinib C(min) was also significantly lower in patients with (n = 18; 942 +/- 330 ng/mL) than without (n = 74; 1,393 +/- 659 ng/mL) major (ie, total or subtotal) gastrectomy (P = .002). In multivariate analysis, albumin (P = .001) concentrations, creatinine clearance (P = .002), and major gastrectomy (P = .003) were significantly correlated with C(min). CONCLUSION In patients with GIST, imatinib C(min) at steady state was significantly associated with albumin concentration, creatinine clearance, and previous major gastrectomy. Although its clinical impact is unclear at present time, monitoring of imatinib C(min) might be particularly important for optimal treatment with imatinib in patients who have undergone major gastrectomy.

p53 Enhances Gefitinib-Induced Growth Inhibition and Apoptosis by Regulation of Fas in Non–Small Cell Lung Cancer

Treatment with gefitinib, a specific inhibitor of epidermal growth factor receptor tyrosine kinase (EGFR-TK), has resulted in dramatic responses in some patients with non-small cell lung cancer (NSCLC). Most patients who respond to gefitinib have EGFR-TK mutations; however, >10% of patients with EGFR-TK mutations do not respond. Similarly, some patients without EGFR-TK mutations respond to this drug, suggesting that other factors determine sensitivity to gefitinib. Aberrations of the tumor suppressor gene p53 are frequently associated with drug resistance. In this study, we investigated the role of p53 in growth-inhibitory and apoptotic effects of gefitinib in the human NSCLC cell lines NCI-H1299 and A549, which have no EGFR-TK mutations. NCI-H1299 cells, which had a p53-null genotype, were more resistant to gefitinib compared with A549 cells, which were wild-type p53 (IC(50), 40 micromol/L in NCI-H1299 and 5 micromol/L in A549). Treatment of A549 with gefitinib resulted in the translocation of p53 from cytosol to nucleus and the up-regulation of Fas, which was localized to the plasma membrane. In the stable H1299 cell line with tetracycline-inducible p53 expression, induced p53 enhanced growth inhibition and apoptosis by gefitinib through the up-regulation of Fas and restoration of caspase activation. A caspase inhibitor, Z-VAD-fmk, reduced these effects. Conversely, inhibition of p53 using antisense oligonucleotide in A549 caused a significant decrease in apoptosis by gefitinib and down-regulation of Fas under the same conditions. In conclusion, p53 may play a role in determining gefitinib sensitivity by regulating Fas expression in NSCLC.

Sorafenib Alone versus Sorafenib Combined with Transarterial Chemoembolization for Advanced-Stage Hepatocellular Carcinoma: Results of Propensity Score Analyses

PURPOSE To compare the time to progression (TTP) and overall survival (OS) in patients with advanced-stage hepatocellular carcinoma (HCC) who are undergoing sorafenib treatment combined with transarterial chemoembolization (TACE) versus sorafenib monotherapy. MATERIALS AND METHODS The retrospective analysis of the data was approved by the institutional review board, and the requirement to obtain informed consent was waived. Of 355 patients with advanced-stage HCC (Barcelona Clinic Liver Cancer stage C) who were undergoing sorafenib therapy for at least 5 weeks between April 2007 and July 2011, 164 (46.2%) underwent repeat TACE (or chemolipiodolization if indicated) along with sorafenib therapy (combined group); the remaining 191 patients (53.8%) received sorafenib alone (monotherapy group). The median patient age was 53 years (range, 22-84 years). The median age was 53 years (range, 26-84 years) for men and 56 years (range, 22-75 years) for women. Propensity score-based methods were used to minimize bias when evaluating TTP on the basis of modified Response Evaluation Criteria in Solid Tumors and OS. Statistical analysis was performed with the Kaplan-Meier method by using the log-rank test and Cox regression models. RESULTS In the combined and monotherapy groups, respectively, 64.6% and 49.2% of patients had vascular invasion, 87.8% and 91.1% had extrahepatic metastasis, and 54.3% and 47.1% had both. During follow-up (median duration, 5.5 months), the median TTP and OS in the combined group were longer than those in the monotherapy group (TTP: 2.5 months vs 2.1 months, respectively, P = .008; OS: 8.9 months vs 5.9 months, P = .009). At univariate and subsequent multivariate analyses, additional TACE was an independent predictor of favorable TTP and OS (adjusted hazard ratio: 0.74 and 0.57, respectively; P < .05 for both), consistent with the outcomes of inverse probability of treatment weighting. In the propensity score-matched cohort (96 pairs), the median TTP in the combined group was significantly longer than that in the monotherapy group (2.7 months vs 2.1 months, respectively; P = .011), but median OS was not (9.1 months vs 6.7 months, P = .21). CONCLUSION In this retrospective study, TACE plus sorafenib was superior to sorafenib alone with respect to TTP in patients with advanced-stage HCC, although it may or may not improve OS. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13130150/-/DC1.

Sorafenib for Recurrent Hepatocellular Carcinoma After Liver Transplantation

OBJECTIVE Sorafenib is the only drug that has shown a survival benefit in patients with hepatocellular carcinoma in randomized Phase 3 trials. The efficacy and safety of sorafenib in the treatment of recurrent hepatocellular carcinoma after liver transplantation, however, has not been determined. METHODS We retrospectively analyzed 13 patients who were treated with sorafenib for recurrent hepatocellular carcinoma after liver transplantation. RESULTS The median time to recurrence from liver transplantation was 12.3 months (95% confidence interval: 8.5-16.1 months). Six of 10 evaluable patients showed stable disease, which was the best response and the median duration of stabilization was 3.9 months (95% confidence interval: 1.6-6.2 months). At a median follow-up duration of 3.7 months (range: 0.3-10.9 months) in surviving patients, the median time to progression and the median overall survival from commencement of sorafenib were 2.9 months (95% confidence interval: 0.0-6.8 months) and 5.4 months (95% confidence interval: 3.7-7.0 months), respectively. Grade 3 neutropenia was observed in one patient, which was the only high-grade hematologic toxicity observed. Grade 3 hand-foot skin reactions were observed in three patients. Adverse events could be managed with dose adjustment. CONCLUSIONS These findings suggest that sorafenib may be a feasible treatment option regarding its efficacy and safety for recurrent hepatocellular carcinoma after liver transplantation.

A phase II study of capecitabine plus 3-weekly oxaliplatin as first-line therapy for patients with advanced gastric cancer

Capecitabine plus oxaliplatin every 3 weeks (XELOX regimen) has proven efficacy in patients with colorectal carcinoma. We investigated this combination in patients with previously untreated advanced gastric carcinoma. The study population comprised patients with histologically confirmed nonresectable advanced gastric adenocarcinoma. Patients received intravenous oxaliplatin 130 mg m−2 over 2 h on day 1 plus oral capecitabine 1000 mg m−2 twice daily on days 1–14, every 3 weeks. Patients received a maximum of eight cycles. Twenty evaluable patients (17 men, 3 women) with a median age of 64 years (range 38–75) were enrolled. The overall response rate was 65% (95% confidence interval (CI), 44–86%), with complete responses in two patients and partial responses in 11 patients. Median progression-free survival was 7.5 months (95% CI, 3.2–11.7 months); median overall survival was not reached during the study period. There was no grade 4 and little grade 3 toxicity. The most common haematological adverse event was anaemia (65% of patients) and the most common nonhaematological toxicities were vomiting (65%), neuropathy (60%), diarrhoea (30%), and hand–foot syndrome (20%). In conclusion, XELOX is apparently as effective as triplet combinations and is well tolerated as first-line therapy for advanced gastric carcinoma. We are starting a large multi-institutional phase II study of XELOX in this setting.