Minoru Takada

Phase III Study of Concurrent Versus Sequential Thoracic Radiotherapy in Combination With Cisplatin and Etoposide for Limited-Stage Small-Cell Lung Cancer: Results of the Japan Clinical Oncology Group Study 9104

PURPOSE To evaluate the optimal timing for thoracic radiotherapy (TRT) in limited-stage small-cell lung cancer (LS-SCLC), the Lung Cancer Study Group of the Japan Clinical Oncology Group conducted a phase III study in which patients were randomized to sequential TRT or concurrent TRT. PATIENTS AND METHODS We treated 231 patients with LS-SCLC. TRT consisted of 45 Gy over 3 weeks (1.5 Gy twice daily), and the patients were randomly assigned to receive either sequential or concurrent TRT. All patients received four cycles of cisplatin plus etoposide every 3 weeks (sequential arm) or 4 weeks (concurrent arm). TRT was begun on day 2 of the first cycle of chemotherapy in the concurrent arm and after the fourth cycle in the sequential arm. RESULTS Concurrent radiotherapy yielded better survival than sequential radiotherapy (P =.097 by log-rank test). The median survival time was 19.7 months in the sequential arm versus 27.2 months in the concurrent arm. The 2-, 3-, and 5-year survival rates for patients who received sequential radiotherapy were 35.1%, 20.2%, and 18.3%, respectively, as opposed to 54.4%, 29.8% and 23.7%, respectively, for the patients who received concurrent radiotherapy. Hematologic toxicity was more severe in the concurrent arm. However, severe esophagitis was infrequent in both arms, occurring in 9% of the patients in the concurrent arm and 4% in the sequential arm. CONCLUSION This study strongly suggests that cisplatin plus etoposide and concurrent radiotherapy is more effective for the treatment of LS-SCLC than cisplatin plus etoposide and sequential radiotherapy.

CPT-11: a new derivative of camptothecin for the treatment of refractory or relapsed small-cell lung cancer.

PURPOSE To evaluate the activity of CPT-11, which is a new derivative of camptothecin, against refractory or relapsed small-cell lung cancer (SCLC). PATIENTS AND METHODS Sixteen patients with refractory or relapsed SCLC were entered onto a prospective, non-randomized, single-institution phase II trial. All 16 patients had been pretreated heavily with some form of cisplatin-based combination chemotherapy. Five patients had received previous chemotherapy with cisplatin, vincristine, doxorubicin, and etoposide (CODE) as an induction therapy. Six patients had been treated with concurrent cisplatin and etoposide plus chest x-ray. The median time off chemotherapy was 7.3 months (range, 1.9 to 15.1 months). Patients were treated with a CPT-11 starting dose of 100 mg/m2 body surface given as a 90-minute intravenous (IV) infusion every week with subsequent doses based on toxicity. Fifteen patients were assessable for toxicity, response, and survival. RESULTS Seven patients (47%; 95% confidence limits for an overall response rate, 21.4% to 71.9%) responded to CPT-11 with a median duration of response of 58 days. The major toxicities were myelosuppression (predominantly leukopenia), diarrhea, and pulmonary toxicity. CONCLUSION CPT-11 is an active agent against refractory or relapsed SCLC and deserves to be studied more closely as both a single agent and in combination with other drugs to treat patients with SCLC.

Activation of ERBB2 Signaling Causes Resistance to the EGFR-Directed Therapeutic Antibody Cetuximab

Several cancers become resistant to cetuximab by activating a bypass signaling pathway and preventing cetuximab inhibition of ERK1/2-stimulated growth. Combating Resistance to an EGF Receptor Inhibitor Many promising anticancer drugs are effective only for a limited time, because the tumor cells develop resistance. Cetuximab, directed against the epidermal growth factor receptor (EGFR), is no exception, and patients with colorectal, head and neck, or non–small cell lung cancer eventually cease to respond to the drug. Yonesaka and colleagues have determined that cetuximab-resistant cancer cells—both in culture and in patients—can up-regulate signaling through the ERBB2 growth factor receptor in several ways, permanently turning on extracellular signal–regulated kinase 1/2 (ERK1/2)–mediated growth, differentiation, and survival. They further show that interference with the ERBB2 pathway restores the ability of cetuximab to control these cancers, pointing to a promising resistance-fighting approach. The authors generated clones of cetuximab-resistant non–small cell lung and colorectal cancer cell lines by exposing the cells to increasing concentration of the drug. In some of these resistant clones, the ERBB2 receptor oncogene was genetically amplified, resulting in activated ERK1/2 signaling. Down-regulation of ERBB2 with a small interfering RNA or antibody restored sensitivity. Other clones did not have amplified ERBB2 genes but did make excess heregulin, an activating ligand for the ERBB2 receptor. Heregulin depletion or ERBB2 inhibition restored cetuximab sensitivity. After replicating these studies in xenografts in mice, the authors also looked for evidence that these resistance-associated alterations pertain to human tumors. In several groups of patients with colorectal cancer, they saw decreased survival or decreased sensitivity to cetuximab in those who exhibited amplified ERBB2 gene or higher heregulin concentrations. The concordance of their cellular data with patient experience improves confidence that concomitant treatment of certain lung, head and neck, or colorectal cancers with cetuximab and an anti-ERBB2 drug may prevent or delay the development of drug resistance. These studies add to other successes for this approach, which has also been used for analysis of other molecular targeted therapies, including EGFR kinase inhibitors. Cetuximab, an antibody directed against the epidermal growth factor receptor, is an effective clinical therapy for patients with colorectal, head and neck, and non–small cell lung cancer, particularly for those with KRAS and BRAF wild-type cancers. Treatment in all patients is limited eventually by the development of acquired resistance, but little is known about the underlying mechanism. Here, we show that activation of ERBB2 signaling in cell lines, either through ERBB2 amplification or through heregulin up-regulation, leads to persistent extracellular signal–regulated kinase 1/2 signaling and consequently to cetuximab resistance. Inhibition of ERBB2 or disruption of ERBB2/ERBB3 heterodimerization restores cetuximab sensitivity in vitro and in vivo. A subset of colorectal cancer patients who exhibit either de novo or acquired resistance to cetuximab-based therapy has ERBB2 amplification or high levels of circulating heregulin. Collectively, these findings identify two distinct resistance mechanisms, both of which promote aberrant ERBB2 signaling, that mediate cetuximab resistance. Moreover, these results suggest that ERBB2 inhibitors, in combination with cetuximab, represent a rational therapeutic strategy that should be assessed in patients with cetuximab-resistant cancers.

Phase III Study of Docetaxel Compared With Vinorelbine in Elderly Patients With Advanced Non–Small-Cell Lung Cancer: Results of the West Japan Thoracic Oncology Group Trial (WJTOG 9904)

PURPOSE Docetaxel has shown activity in elderly patients with advanced non-small-cell lung cancer (NSCLC). This randomized phase III trial evaluated the efficacy and safety of docetaxel versus vinorelbine (the current standard treatment) in elderly patients. PATIENTS AND METHODS Chemotherapy-naïve patients age 70 years or older with stage IIIB/IV NSCLC and performance status 2 or lower were eligible. Patients randomly received docetaxel 60 mg/m2 (day 1) or vinorelbine 25 mg/m2 (days 1 and 8) every 21 days for four cycles. The primary end point was overall survival. Overall disease-related symptom improvement was assessed using an eight-item questionnaire. RESULTS In total, 182 patients were enrolled. Median age was 76 years (range, 70 years to 86 years). There was no statistical difference in median overall survival with docetaxel versus vinorelbine (14.3 months v 9.9 months; hazard ratio, 0.780; 95% CI, 0.561 to 1.085; P = .138). There was a significant difference in median progression-free survival (5.5 months v 3.1 months; P < .001). Response rates were also significantly improved with docetaxel versus vinorelbine (22.7% v 9.9%; P = .019). The most common grade 3 to 4 toxicities were neutropenia (82.9% for docetaxel; 69.2% for vinorelbine; P = .031) and leukopenia (58.0% for docetaxel; 51.7% for vinorelbine). Other toxicities were mild and generally well tolerated. Docetaxel improved overall disease-related symptoms over vinorelbine (odds ratio, 1.86; 95% CI, 1.09 to 3.20). CONCLUSION Docetaxel improved progression-free survival, response rate, and disease-related symptoms versus vinorelbine. Overall survival was not statistically significantly improved at this time. Docetaxel monotherapy may be considered as an option in the standard treatment of elderly patients with advanced NSCLC.

Requirement of caspase-3(-like) protease-mediated hydrogen peroxide production for apoptosis induced by various anticancer drugs.

Caspase-3(-like) proteases play important roles in controlling mammalian apoptosis. However, the downstream events from the caspase-3(-like) protease activation to death of cells are still unclear. Previously, we reported that hydrogen peroxide (H2O2) was generated by the activation of caspase-3(-like) proteases in the process of tyrosine kinase inhibitor-induced apoptosis in human small cell lung carcinoma Ms-1 cells. In the present study, we examined whether generation of H2O2 is a critical event for the apoptotic pathway downstream of caspase-3(-like) protease activation by various anticancer drugs. Anticancer drugs such as camptothecin, vinblastine, inostamycin, and adriamycin induced activation of caspase-3(-like) proteases and apoptosis. Generation of H2O2 was commonly detected after treatment with each of the four anticancer drugs, and scavenging of H2O2 caused cells to fail to undergo apoptosis. Moreover, anticancer drug-induced H2O2 production was inhibited not only by an inhibitor of caspase-3(-like) proteases but also by diphenyleneiodonium chloride, an inhibitor of flavonoid-containing enzymes such as NADPH oxidase. However, activation of caspase-3(-like) proteases was not inhibited by diphenyleneiodonium chloride. These findings suggest that activation of caspase-3(-like) proteases by various anticancer drugs causes generation of H2O2 presumably through the activation of NADPH oxidase, thereby inducing apoptosis. Therefore, H2O2 may function as a common mediator for apoptosis induced by various anticancer drugs.

EGFR and erbB2 mutation status in Japanese lung cancer patients

Much evidence has accumulated that the epidermal growth factor receptor (EGFR) and its family members are strongly implicated in the development and progression of lung cancers. Somatic mutations of the EGFR gene were found in about 25–40% of Japanese lung cancer patients. More recently, erbB2 mutations are found in about 4% of European‐derived lung cancer patients. We have investigated EGFR and erbB2 mutation status in 95 surgically treated nonsmall cell lung cancer (NSCLC) cases from Nagoya City University Hospital. Seventy‐five adenocarcinoma cases were included. The presence or absence of EGFR and ernB2 mutations of kinase domains were analyzed by reverse transcription polymerase chain reaction (RT‐PCR) amplifications and direct sequences. We have also investigated erbB2 mutation status in 27 surgically treated NSCLC cases followed by treatment with gefitinib from Kinki‐chuo Chest Medical Center. EGFR mutations (CTG→CGG; L858R) were found from 14 of 95 lung cancer patients. We also detected the deletion 1a‐type mutations from 9 patients and deletion 4‐type mutations from 6 patients in exon 19. In exon 20, 4 mutations including 2 novel mutations were found. Total EGFR mutations were present in 35 patients (36.8%). These mutation statuses were significantly correlated with gender (women 73.3% vs. men 20%, p < 0.0001), smoking status (never smoker 69.4% vs. smoker 16.9%, p < 0.0001), pathologic subtypes (adenocarcinoma 45.1% vs. nonadenocarcinoma 12.5%, p = 0.0089) and differentiation status of the lung cancers (well 51% vs. moderately or poorly 18.4%, p = 0.0021). On the other hand, erbB2 mutation was only found from 1 of 95 patients, at exon 20. This patient was female and a never smoker with adenocarcinoma. This 12 nucleotide insertion mutation (2324–2325 ins ATACGTGATGGC) was located in the exon 20 at kinase domain (775–776 ins YVMA). There was no erbB2 mutation in 27 gefitinib‐treated NSCLC patients. In total, we have found only 1 erbB2 mutation from 122 (0.8%) Japanese NSCLC patients. There was a significantly higher erbB2 positive (2+/3+) ratio in EGFR mutant patients (13/25, 52.0%) compared to EGFR wild‐type patients (10/62, 16.1%; p = 0.0247). The NSCLC specimen with erbB2 mutation showed 1+ immunoreactivity. The EGFR mutation status might correlate with the clinicopathologic features related to good response to gefitinib, such as gender, smoking history and pathologic subtypes of lung cancers. However, erbB2 mutation is rare from Japanese lung cancer and is of limited value for molecular target therapy.

Frequent and histological type-specific inactivation of 14-3-3σ in human lung cancers

One isoform of the 14-3-3 family, 14-3-3σ, plays a crucial role in the G2 checkpoint by sequestering Cdc2-cyclinB1 in the cytoplasm, and the expression of 14-3-3σ is frequently lost in breast cancers. This loss of expression is thought to cause a G2 checkpoint defect, resulting in chromosomal aberrations. Since lung cancers frequently carry numerous chromosomal aberrations, we examined the DNA methylation status and expression level of the 14-3-3σ gene in 37 lung cancer cell lines and 30 primary lung tumor specimens. We found that small cell lung cancer (SCLC) cell lines frequently showed DNA hypermethylation (9 of 13 lines, 69%), and subsequent silencing of the 14-3-3σ gene. Among non-small cell lung cancers (NSCLC), large cell lung cancer cell lines showed frequent hypermethylation and silencing of 14-3-3σ (4 or 7 lines, 57%). In contrast, in other NSCLC cell lines, hypermethylation occurred very rarely (1 of 17 lines, 6%). All eight primary SCLC specimens examined also showed a loss or significant reduction in 14-3-3σ expression in vivo, while a loss or reduction of 14-3-3σ expression was very rare in primary NSCLC specimens (1 of 22 tissues, 5%). This is the first description that indicates lung cancers frequently show significant inactivation of the 14-3-3σ gene mainly due to DNA hypermethylation in SCLC, but rarely in NSCLC, suggesting involvement of the 14-3-3σ gene in lung tumorigenesis in a histological type-specific manner.

Randomized Phase III Trial of Erlotinib Versus Docetaxel As Second- or Third-Line Therapy in Patients With Advanced Non–Small-Cell Lung Cancer: Docetaxel and Erlotinib Lung Cancer Trial (DELTA)

PURPOSE To investigate the efficacy of erlotinib versus docetaxel in previously treated patients with advanced non-small-cell lung cancer (NSCLC) in an epidermal growth factor receptor (EGFR) -unselected patient population. PATIENTS AND METHODS The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), response rate, safety, and analyses on EGFR wild-type tumors. Patients with stage IIIB or IV NSCLC, previous treatment with one or two chemotherapy regimens, evaluable or measurable disease, and performance status of 0 to 2 were eligible. RESULTS From August 2009 to July 2012, 150 and 151 patients were randomly assigned to erlotinib (150 mg daily) and docetaxel (60 mg/m(2) every 3 weeks), respectively. EGFR wild-type NSCLC was present in 109 and 90 patients in the erlotinib and docetaxel groups, respectively. Median PFS for erlotinib versus docetaxel was 2.0 v 3.2 months (hazard ratio [HR], 1.22; 95% CI, 0.97 to 1.55; P = .09), and median OS was 14.8 v 12.2 months (HR, 0.91; 95% CI, 0.68 to 1.22; P = .53), respectively. In a subset analysis of EGFR wild-type tumors, PFS for erlotinib versus docetaxel was 1.3 v 2.9 months (HR, 1.45; 95% CI, 1.09 to 1.94; P = .01), and OS was 9.0 v 10.1 months (HR, 0.98; 95% CI, 0.69 to 1.39; P = .91), respectively. CONCLUSION Erlotinib failed to show an improvement in PFS or OS compared with docetaxel in an EGFR-unselected patient population.

CPT-11 in combination with cisplatin for advanced non-small-cell lung cancer.

PURPOSE The purpose of this study was to determine the maximum-tolerated dose and the dose-limiting toxicities of CPT-11, a new derivative of camptothecin, in combination with a fixed dose of cisplatin in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Twenty-seven previously untreated patients with stage IIIB or IV NSCLC were assessable for toxicity, and 26 were assessable for response. The initial dose of CPT-11 was 30 mg/m2 given as a 90-minute intravenous (IV) infusion on days 1, 8, and 15 in combination with cisplatin (80 mg/m2 IV on day 1) given every 4 weeks. The dose of CPT-11 was escalated in increments of 10 mg/m2 until severe or life-threatening toxic effects were observed. RESULTS Significant toxicity was infrequent up to 60 mg/m2 of CPT-11. The maximum-tolerated toxicity was reached at a dose of 70 mg/m2. Three of six patients either had leukocyte count nadirs of less than 2,000/microL or experienced grade 4 diarrhea during the first cycle of therapy at 70 mg/m2. The major toxic effects were leukopenia and diarrhea. There were 14 partial responses (54%) among the 26 patients. CONCLUSIONS A combination of CPT-11 and cisplatin seems to be effective against NSCLC with acceptable toxicities. The recommended dose for phase II studies is 60 mg/m2 of CPT-11 on days 1, 8, and 15, and 80 mg/m2 of cisplatin on day 1 every 4 weeks.

Performance Status and Smoking Status Are Independent Favorable Prognostic Factors for Survival in Non-small Cell Lung Cancer: A Comprehensive Analysis of 26,957 Patients with NSCLC

Background: Performance status (PS) is an important factor in determining survival outcome in non-small cell lung cancer (NSCLC) but is generally confounded by stage, age, gender, and smoking status. We investigated the prognostic significance of PS taking into account these important factors. Methods: Retrospective analysis of registry database of the National Hospital Study Group for Lung Cancer (NHSGLC) between1990 and 2005. Univariate analysis was performed using Kaplan-Meier method. Multivariate analysis was performed using Cox proportional hazards model to identify independent prognostic factors. Results: A total of 26,957 patients with NSCLC were analyzed of which 12,613 patients (46.8%) had World Health Organization (WHO) PS = 0, 8,137 patients were never smokers (30.2%), and most of them were females (72.7%). The majority of PS = 0 patients presented with stage I disease (56.9%). Patients with PS = 0 constituted the group with the highest proportion of never smokers (36.7%). There was a significant difference in the median overall survival (OS) between patients with PS = 0 and PS = 1 (51.5 months versus 15.4 months, respectively; p < 0.0001) and among patients with various PS within individual American Joint Committee on Cancer stage (all p values <0.0001). Never smokers had significantly improved median OS than ever smokers (30.0 months versus 19.0 months, respectively; p < 0.0001). Multivariate analysis demonstrated good PS, never smoker (versus ever smoker; hazard ratio = 0.935, 95% confidence interval: 0.884–0.990; p = 0.0205), early stage, female gender, squamous cell carcinoma histology, and treatment were all as independent favorable prognostic factors. Conclusions: PS and smoking status are independent prognostic factors for OS in NSCLC.