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Retrospective analysis has shown that activating mutations in exons 18-21 of the epidermal growth factor receptor (EGFR) gene are a predictor of response to gefitinib. We conducted a phase II trial to evaluate the efficacy and safety of gefitinib as first-line therapy for advanced non-small cell lung cancer (NSCLC) with EGFR mutations. Patients with stage IIIB or IV chemotherapy-naïve NSCLC with EGFR mutation were treated with 250 mg gefitinib daily. For mutational analysis, DNA was extracted from paraffin-embedded tissues and EGFR mutations were analysed by direct sequence of PCR products. Twenty (24%) of the 82 patients analysed had EGFR mutations (deletions in or near E746-A750, n=16; L858R, n=4). Sixteen patients were enrolled and treated with gefitinib. Twelve patients had objective response and response rate was 75% (95% CI, 48-93%). After a median follow-up of 12.7 months (range, 3.1-16.8 months), 10 patients demonstrated disease progression, with median progression-free survival of 8.9 months (95% CI, 6.7-11.1 months). The median overall survival time has not yet been reached. Most of the toxicities were mild. This study showed that gefitinib is very active and well tolerated as first-line therapy for advanced NSCLC with EGFR mutations. [ABSTRACT FROM AUTHOR]

By presenting immunogenic peptides at the cell surface, major histocompatibility complex (MHC) class II molecules play a key role in the control of adaptive immune responses. Whether expressed constitutively or induced by interferon-?, expression of MHC class II molecules is regulated via coactivator class II transactivator (CIITA); moreover, suppression of their expression is one mechanism by which cancer cells escape host immunity. In this study, we surveyed the relationship between the expression of one MHC class II antigen, HLA-DR, and its coactivators in a group of haematopoietic cell lines, and explored the role of the aberrant DNA methylation in silencing HLA-DR expression. Among 26 cell lines studied, HLA-DR expression was lost from eight T-cell and two myeloid leukaemia cell lines, and this loss was closely associated with suppression of CIITA-PIV expression. Notably, nine of the 10 cell lines that lost CIITA-PIV expression showed methylation of the gene's 5' CpG island. Thus, DNA methylation is believed to inhibit the expression of MHC class II molecules in haematopoietic tumour cells by silencing its coactivator, CIITA-PIV. Furthermore, methylation of CIITA-PIV was detected in seven of 32 primary acute myeloid leukaemia specimens, indicating that epigenetic alteration is not a cell line-specific phenomenon. Collectively, these data suggest that, by suppressing expression of MHC class II molecules, epigenetic inactivation of CIITA provides a survival advantage to a subset of haematopoietic tumours.British Journal of Cancer (2004) 90, 844-852. doi:10.1038/sj.bjc.6601602 www.bjcancer.com [ABSTRACT FROM AUTHOR]

Background: The optimal number of neoadjuvant chemotherapy (NAC) cycles remains to be established for treating oesophageal squamous cell carcinoma (ESCC). We compared two versus three courses of NAC for treating locally advanced ESCC in a multi-institutional, randomised, Phase II trial., Methods: We randomly assigned 180 patients with locally advanced ESCC at 6 institutions to either two (N = 91) or three (N = 89) courses of DCF (docetaxel 70 mg/m 2 , cisplatin 70 mg/m 2 i.v. on day 1, fluorouracil 700 mg/m 2 continuous infusion for 5 days) every 3 weeks, prior to surgery. The primary endpoint was 2-year progression-free survival (PFS) with an intention-to-treat analysis., Results: Patient background parameters were well-balanced. The R0 resection rates were 98.9 and 96.5% in the two- and three-course groups, respectively (P = 0.830). In resected cases, the two- and three-course groups had comparable pN0 rates (P = 0.225) and histological responses (P = 0.898). The 2-year PFS rate was also comparable between the two groups (71.4 vs. 71.1%, P = 0.669). Among subgroups based on baseline characteristics, only patients aged under 65 years old showed a tendency for better survival with the three-course treatment (hazard ratio = 2.612, 95% confidence interval: 1.012-7.517)., Conclusions: Two courses of a DCF regimen showed potential as an optional NAC treatment for locally advanced ESCC., Clinical Trial Registration: University Hospital Medical Information Network Clinical Trials Registry of Japan (identification number UMIN 000015788)., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: Despite the effectiveness of tyrosine kinase inhibitors (TKI), gastrointestinal stromal tumours (GIST) develop after the withdrawal of TKI. Based on previous studies, a subpopulation of drug-tolerant cells called "persister cells" may be responsible for the recurrence and have thus, gained attention as a novel target in cancer therapy., Methods: The metabolic changes were investigated in imatinib-derived persister GIST cells. We investigated the efficacy and the mechanism of GPX4 inhibitor, which is known as a major inducer of "ferroptosis". We also evaluated the effects of RSL3 to the gefitinib-derived persister lung cancer cells., Results: We demonstrated a downregulation of glucose metabolism, subsequent decrease in the glutathione level and sensitivity to glutathione peroxidase 4 (GPX4) inhibitor, RSL3 in persister cells. As the cell death induced by RSL3 was found to be "iron-dependent" and "caspase-independent", loss of GPX4 function could have possibly induced selective persister cell ferroptotic death. In the xenograft model, we confirmed the inhibition of tumour regrowth after discontinuation of imatinib treatment. Moreover, RSL3 prevented the growth of gefitinib-derived persister lung cancer cells., Conclusions: RSL3 combined with TKI may be a promising therapy for both GIST and epidermal growth factor receptor-mutated lung cancer., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: Despite the effectiveness of imatinib mesylate (IM), most gastrointestinal stromal tumours (GISTs) develop IM resistance, mainly due to the additional kinase-domain mutations accompanied by concomitant reactivation of KIT tyrosine kinase. Heat-shock protein 90 (HSP90) is one of the chaperone molecules required for appropriate folding of proteins such as KIT., Methods: We used a novel HSP90 inhibitor, TAS-116, which showed specific binding to HSP90α/β with low toxicity in animal models. The efficacy and mechanism of TAS-116 against IM-resistant GIST were evaluated by using IM-naïve and IM-resistant GIST cell lines. We also evaluated the effects of TAS-116 on the other HSP90 client protein, EGFR, by using lung cell lines., Results: TAS-116 inhibited growth and induced apoptosis in both IM-naïve and IM-resistant GIST cell lines with KIT activation. We found KIT was activated mainly in intracellular compartments, such as trans-Golgi cisternae, and TAS-116 reduced autophosphorylated KIT in the Golgi apparatus. In IM-resistant GISTs in xenograft mouse models, TAS-116 caused tumour growth inhibition. We found that TAS-116 decreased phosphorylated EGFR levels and inhibited the growth of EGFR-mutated lung cancer cell lines., Conclusion: TAS-116 may be a novel promising drug to overcome tyrosine kinase inhibitor-resistance in both GIST and EGFR-mutated lung cancer.