In vitro Simulation Study of Individualized Chemotherapy in Lung Cancer

The primary aim of this in vitro simulation study was to evaluate the utility of gene expression profile analysis in predicting the effect of varying drug combinations for the treatment of lung cancer. Using 10 human cancer cell lines, we focused our gene expression analysis on a cohort of candidate sensitivity-prediction factors, previously reported using cDNA filter arrays, with a view to predicting the ability of a set of anti-cancer drugs commonly used to treat lung cancer, namely cisplatin, 5-fluorouracil (5FU), SN38, docetaxel, gemcitabine, and vinorelbine. Altered expression of genes for glutathione-S-transferase-pi, uridine phosphorylase, O-6-methylguanine-DNA methyltransferase, and multidrug resistance 1 was identified in lung cancer cell lines. Drug sensitivity testing, in the form of methylthiotetrazol analysis, was performed using these six anti-cancer drugs against the panel of 10 lung cancer cell lines. We compared the predicted chemosensitivity based on the gene expression pattern of 19 well-known sensitivity-related genes with the cytotoxic activity of each of these anti-cancer drugs. Molecular profiling data predicted resistance to CDDP in LK-2 cells, 5FU in LK-2, PC7, A549, NCI-N231, Lu135 cells, irinitecan in PC9 cells, and VNR in PC7 cells. However, the prediction efficacy (number of predicted inactive drugs by gene expression analysis/number of inactive drugs by methylthiotetrazol assay) was 21.6% (8 of 37). No false-positive findings in relation to sensitivity-related genes were obtained on the basis of this molecular analysis. Thus, prediction of sensitivity to lung cancer by molecular analysis appears possible. With elucidation of additional drug sensitivity factors, selection of appropriate anticancer drugs by gene expression profiling may make it possible to increase the response rate in lung cancer chemotherapy.

Phase I/II study of paclitaxel + carboplatin for refractory or recurrent non-small cell lung cancer

A gene-drug correlation analysis was previously performed in lung cancer cell lines using the NC160 program. On the basis of this work, a phase I/II pilot study of weekly paclitaxel and carboplatin (CBDCA) was subsequently planned for refractory or recurrent non-small cell lung cancer (NSCLC). Safety and antitumor effects were evaluable in all 30 patients registered for this study. Seven patients were stage IIIB and 23 were stage IV. At level 5 (paclitaxel 100 mg/m2 and CBDCA AUCS), toxicities were not dose-limiting factors, but three out of the initial six cases had infusion skips. Our recommended dose was paclitaxel 100 mg/m2 and CBDCA AUC5. The response rate was 50% (9/18)(95% CI: 27-73%) in step 5. The median survival time was 12 months. This combination showed a promising clinical activity with mild toxicity and should be selected for the investigational arm of phase III trials to be compared with either docetaxel or pemetrexed.

Anticancer drug clustering in lung cancer based on gene expression profiles and sensitivity database

background

The effect of current therapies in improving the survival of lung cancer patients remains far from satisfactory. It is consequently desirable to find more appropriate therapeutic opportunities based on informed insights. A molecular pharmacological analysis was undertaken to design an improved chemotherapeutic strategy for advanced lung cancer.

Methods

We related the cytotoxic activity of each of commonly used anti-cancer agents (docetaxel, paclitaxel, gemcitabine, vinorelbine, 5-FU, SN38, cisplatin (CDDP), and carboplatin (CBDCA)) to corresponding expression pattern in each of the cell lines using a modified NCI program.

Results

We performed gene expression analysis in lung cancer cell lines using cDNA filter and high-density oligonucleotide arrays. We also examined the sensitivity of these cell lines to these drugs via MTT assay. To obtain our reproducible gene-drug sensitivity correlation data, we separately analyzed two sets of lung cancer cell lines, namely 10 and 19. In our gene-drug correlation analyses, gemcitabine consistently belonged to an isolated cluster in a reproducible fashion. On the other hand, docetaxel, paclitaxel, 5-FU, SN-38, CBDCA and CDDP were gathered together into one large cluster.

Conclusion

These results suggest that chemotherapy regimens including gemcitabine should be evaluated in second-line chemotherapy in cases where the first-line chemotherapy did not include this drug. Gene expression-drug sensitivity correlations, as provided by the NCI program, may yield improved therapeutic options for treatment of specific tumor types.

Reduction of PTEN protein and loss of epidermal growth factor receptor gene mutation in lung cancer with natural resistance to gefitinib (IRESSA)

Gefitinib (IRESSA), an epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitor, has antitumour activity in the advanced non-small-cell lung cancer (NSCLC) setting. However, in chemotherapy-naïve patients with advanced NSCLC, the addition of gefitinib to standard chemotherapy regimens failed to increase survival. These results suggest the need for improved patient selection and combination rationales for targeted therapies. We have identified subpopulations of an adenocarcinoma cell line that are naturally resistant to gefitinib, and have analysed the cDNA expression profiles, genomic status of EGFR gene and the effect of gefitinib on signalling pathways in these cell lines in order to identify key mechanisms for naturally acquired resistance to gefitinib. Gefitinib-resistant subpopulations demonstrated increased Akt phosphorylation (not inhibited by gefitinib), reduced PTEN protein expression and loss of the EGFR gene mutation when compared with parental cell lines. These differences in Akt and PTEN protein expression were not evident from the cDNA array profiles. These data suggests that (1) the EGFR gene mutation may be possibly lost in some cancer cells with other additional mechanisms for activating Akt, (2) reintroduction of PTEN or pharmacological downregulation of the constitutive PI3K-Akt-pathway activity may be an attractive therapeutic strategy in cancers with gefitinib resistance.

[A case of secondary pulmonary cryptococcosis showing various radiographic changes during its natural course without antifungal treatment]

A 58-year-old man who had been prescribed corticosteroids for rheumatoid arthritis in another hospital was admitted to our hospital for examination of an abnormal chest shadow. We obtained a positive result for cryptococcal antigen in the serum, in a measurement done as a screening test for abnormal chest shadows. We diagnosed secondary pulmonary cryptococcosis through a transbronchial biopsy. He showed various radiographic changes, including multiple nodular shadows, cavities and partial resolution during the natural course without antifungal treatment. This case taught us that secondary pulmonary cryptococcosis causes a more varied range of radiographic changes than its primary form, that measurement of cryptococcal antigen in serum is useful as a screening test of pulmonary cryptococcosis, and that it is important to consider whether a particular patient should be treated or not.

Real-time telediagnosis of radiological images through an asynchronous transfer mode network: the ARTeMeD project

The ARTeMeD project aims to solve problems of interactivity and real-time in teleradiology. It integrates personal multimedia facilities and patient data access in a common platform that allows radiologists to collaborate from remote sites through a suitable communication support. ARTeMeD is based on asynchronous transfer mode (ATM) network technology and an optimized manipulation of medical image material. The ARTeMeD system opens interesting perspectives in the area of collaborative teleradiology.