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Despite initial dramatic response, epidermal growth factor receptor (EGFR) mutant lung cancer patients always acquire resistance to EGFR-tyrosine kinase inhibitors (TKIs). Gatekeeper T790M mutation in EGFR is the most prevalent genetic alteration underlying acquired resistance to EGFR-TKI, and EGFR mutant lung cancer cells are reported to be addictive to EGFR/Akt signaling even after acquired T790M mutation. Here, we focused on Akt kinase-interacting protein1 (Aki1), a scaffold protein of PI3K (phosphoinositide 3-kinase)/PDK1 (3-phosphoinositide-dependent protein kinase)/Akt that determines receptor signal selectivity for non-mutated EGFR, and assessed its role in EGFR mutant lung cancer with or without gatekeeper T790M mutation. Cell line-based assays showed that Aki1 constitutively associates with mutant EGFR in lung cancer cells with (H1975) or without (PC-9 and HCC827) T790M gatekeeper mutation. Silencing of Aki1 induced apoptosis of EGFR mutant lung cancer cells. Treatment with Aki1 siRNA dramatically inhibited growth of H1975 cells in a xenograft model. Moreover, silencing of Aki1 further potentiated growth inhibitory effect of new generation EGFR-TKIs against H1975 cells in vitro. Aki1 was frequently expressed in tumor cells of EGFR mutant lung cancer patients (53/56 cases), including those with acquired resistance to EGFR-TKI treatment (7/7 cases). Our data suggest that Aki1 may be a critical mediator of survival signaling from mutant EGFR to Akt, and may therefore be an ideal target for EGFR mutant lung cancer patients, especially those with acquired EGFR-TKI resistance due to EGFR T790M gatekeeper mutation. [ABSTRACT FROM AUTHOR]

Preoperative chemotherapy is a promising strategy in patients with early-stage resectable non-small-cell lung cancer (NSCLC); optimal chemotherapy remains unclear. Clinical (c-) stage IB/II NSCLC patients were randomised to receive either two cycles of docetaxel (D)-cisplatin (P) combination chemotherapy (D 60 mg m(-2) and P 80 mg m(-2) on day 1) every 3-4 weeks or three cycles of D monotherapy (70 mg m(-2)) every 3weeks. Thoracotomy was performed 4-5 weeks (DP) or 3-4 weeks (D) after chemotherapy. The primary end point was 1-year disease-free survival (DFS). From October 2002 to November 2003, 80 patients were randomised. Chemotherapy toxicities were mainly haematologic and well tolerated. There were two early postoperative deaths with DP (one intraoperative bleeding and one empyema). Pathologic complete response was observed in two DP patients. Docetaxel-cisplatin was superior to D in terms of response rate (45 vs 15%) and complete resection rate (95 vs 87%). Both DFS and overall survival were better in DP. Disease-free survival at 1, 2 and 4 years were 78, 65 and 57% with DP, and were 62, 44 and 36% with D, respectively. Preoperative DP was associated with encouraging resection rate and DFS data, and phase III trials for c-stage IB/II NSCLC are warranted. [ABSTRACT FROM AUTHOR]

Although widespread metastasis is the major cause of human lung cancer-related deaths, its underlying mechanism remains largely unclear. Our genome-wide comparison of the expression profiles of a highly metastatic lung cancer cell line, NCI-H460-LNM35 (LNM35), and its parental clone, NCI-H460-N15 (N15), resulted in the identification of a cancer metastasis signature composed of 45 genes. Through gene ontology analysis, our study also provided insights into how this 45-gene metastasis signature may contribute to the acquisition of metastatic potential. By applying the signature to datasets of human cancer cases, we could demonstrate significant associations with a subset of cases with poor prognosis not only for the two datasets of cancers of the lung but also for cancers of the breast. Furthermore, we were able to show that enforced expression of the DLX4 homeobox gene, which was identified as a gene with significant downregulation in LNM35 as well as with significant association with favorable prognosis for lung cancer patients, markedly inhibited in vitro motility and invasion as well as in vivo metastasis via both hematogenous and lymphogenous routes. Taken together, these findings indicate that our combined transcriptome analysis is an efficient approach in the search for genes possessing both clinical usefulness in terms of prognostic prediction in human cancer cases and clear functional relevance for studying cancer biology in relation to metastasis.Oncogene (2007) 26, 4600–4608; doi:10.1038/sj.onc.1210242; published online 29 January 2007 [ABSTRACT FROM AUTHOR]

This study aimed to identify predictive factors associated with prognostic benefits of gefitinib. A total of 221 Japanese patients who received gefitinib (250 mg day−1) were examined retrospectively and potential predictive factors analysed. Overall response rate (ORR) was 24.4% and median survival time (MST) was 8.0 months. In a log-rank test, survival was significantly better in females, patients with adenocarcinoma, never-smokers, favourable performance status (PS) and patients with epidermal growth factor receptor (EGFR) mutation. The lower the smoking exposure (Brinkman Index (BI)=cigarettes per day × years smoked), the better the MST (BI 0: 14.5 months, BI <500: 9.5 months, BI 500 to <1000: 6.9 months, BI 1000: 4.0 months). Positive-EGFR mutation status and PS 0–1 were independent predictors of favourable prognosis by multivariate analysis. Prognosis was significantly different according to EGFR mutation status (with the same smoking status), but not according to smoking status (with the same EGFR mutation status). EGFR mutation status is the most important independent predictor of survival benefit with gefitinib treatment. Although differences in prognosis were observed according to relative smoking status and smoking exposure, the results suggested that smoking is not a direct predictor of prognosis, yet is a surrogate marker of EGFR mutation status.British Journal of Cancer (2007) 96, 1191–1196. doi:10.1038/sj.bjc.6603710 www.bjcancer.com Published online 27 March 2007 [ABSTRACT FROM AUTHOR]

Subsets of patients with non-small cell lung cancer respond remarkably well to small molecule tyrosine kinase inhibitors (TKI) specific for epidermal growth factor receptor (EGFR) such as gefitinib or erlotinib. In 2004, it was found that EGFR mutations occurring in the kinase domain are strongly associated with EGFR-TKI sensitivity. However, subsequent studies revealed that this relationship was not perfect and various predictive markers have been reported. These include EGFR gene copy numbers, status of ligands for EGFR, changes in other HER family genes or molecules downstream to EGFR including KRAS or AKT. In this review, we would like to review current knowledge of predictive factors for EGFR-TKI. As all but one phase III trials failed to show a survival advantage of the treatment arm involving EGFR-TKIs, it is necessary to select patients by these biomarkers in future clinical trials. Through these efforts, it would be possible to individualise EGFR-TKI treatment for patients suffering from lung cancer.British Journal of Cancer (2007) 96, 857–863. doi:10.1038/sj.bjc.6603665 www.bjcancer.com Published online 27 February 2007 [ABSTRACT FROM AUTHOR]

Methods. The cases were 102 patients with esophageal cancer, 143 with stomach cancer, 74 with colon cancer, 72 with rectal cancer, 192 with lung cancer, 237 with breast cancer, 56 with prostate cancer, and 108 with malignant lymphoma. Controls consisted of outpatients from two sources: 241 noncancer outpatients who underwent gastroscopy and 399 first-visit outpatients, expected to include about 20% with cancer. Genotyping was conducted by polymerase chain reaction with confronting two-pair primers (PCR-CTPP). Results. The TT genotype with null enzyme activity was found in 19.9% of the 241 noncancer gastroscopy examinees, 16.5% of the 399 first-visit outpatients, 12.7% of the esophageal cancer patients, 16.8% of the stomach cancer patients, 13.5% of the colon cancer patients, 9.7% of the rectal cancer patients, 17.7% of the lung cancer patients, 14.3% of the breast cancer patients, 16.1% of the prostate cancer patients, and 15.7% of the malignant lymphoma patients. The odds ratios (ORs) of the genotypes were not significant for any cancers combined or for any site of cancer, except for lung cancer (OR, 0.66; 95% confidence interval [CI], 0.46–0.96 for CT relative to CC). The OR of current smoking for cancers of the esophagus and lung combined was different between the CC genotype (OR, 2.06; 95% CI, 1.06–3.98) and TT genotype (OR, 5.11; 95% CI, 1.37–19.05), although the difference was not significant. Conclusion. This study suggests that the CC genotype of the NQO1 C609T polymorphism is associated with the risk of lung cancer, and that the TT genotype increases the risk of smoking for cancers of the esophagus and lung. [ABSTRACT FROM AUTHOR]

To investigate risk modification for lung cancer with diet in Japanese, we conducted a hospital-based case-control study and evaluated variation in influence with the histological type. We recruited 367 male and 240 female cases with adenocarcinomas, and 381 male and 57 female cases with squamous cell and small cell carcinomas. Controls comprised 2964 male and 1189 female cancer-free outpatients matched for sex and age with the cases. Odds ratios (ORs) and their 95% confidence intervals (Cls) for lung cancer were calculated with adjustment for potential confounding factors, using an unconditional logistic model. We found decreased ORs for adenocarcinomas in both males (OR = 0.51, 95% Cl 0.31-0.84) and females (OR = 0.48, 95% Cl 0.24-0.94) who consumed cooked/raw fish, but not dried/salted fish at the highest quartile frequency, compared with the lowest. Soybean curd consumption was associated with a decreased OR for female adenocarcinomas. Decreased ORs for squamous cell and small cell carcinomas were observed in males with frequent consumption of raw and green vegetables, fruit and milk, but consumption of carrot, pumpkin, egg and coffee was associated with increased ORs. This study suggests cooked/raw fish consumption lowers the risk of adenocarcinoma of the lung in Japanese. [ABSTRACT FROM AUTHOR]