Establishment and characterization of amylase-producing lung adenocarcinoma cell line, IMEC-2.

BACKGROUND: Few studies have successfully established an amylase-producing lung cancer cell line or have examined its cytological, biochemical and biological features. PATIENTS AND METHODS: Cancer cells, isolated from pleural effusion using a gradient method, were cultivated. RESULTS: Amylase production from the newly established cell line was confirmed by positive staining for alpha-amylase and increased amylase levels in the culture supernatant. Electron microscopy revealed zymogen granule-like structures. Sialylation of salivary-type amylase was confirmed directly from the cell line by examining the neuraminidase sensitivity and amylase elution profile under high-performance liquid chromatography. Neither EGFR or KRAS mutation were found. CONCLUSION: This cell line offers a useful tool for analyzing the pathogenesis and pathophysiology of amylase-producing lung cancers. Moreover, it might be useful for probing the metastasis and invasiveness of lung cancer cells and for developing an early diagnostic method based on sialylated salivary-amylase production.

A case of idiopathic pulmonary alveolar proteinosis accompanied by T-cell receptor gene rearrangement in bronchoalveolar lavage fluid cells.

We describe a case of a patient with idiopathic pulmonary alveolar proteinosis (PAP), who had an elevated serum level of antigranulocyte-macrophage colony stimulating factor (anti-GM-CSF) antibody accompanied by T-cell receptor gene rearrangements in BAL fluid cells. Histopathological examination of the lung excluded lymphoma but revealed PAP and silicosis. There was no detectable serum anti-GM-CSF antibody in 50 outpatients with advanced silicosis who did not have PAP, suggesting that anti-GM-CSF antibody is directly linked to PAP but not to silicosis. We speculate that monoclonal expansion of a T-cell population may play a role in the production of anti-GM-CSF antibody and the development of PAP.

Intracellular conversion of irinotecan to its active form, SN-38, by native carboxylesterase in human non-small cell lung cancer.

The anticancer agent irinotecan (CPT-11) is a prodrug converted to its active form, SN-38, by human carboxylesterase (hCE) and the SN-38 is further metabolized to its inactive form, SN-38G. We investigated the expression of hCE in human lung cancer cells as well as the ability of these cells to convert CPT-11 to SN-38 using surgically resected tumor samples and cultured cell lines. SN-38 was 40- to 3,000-fold more toxic to lung cancer cell lines than CPT-11, which acted more time-dependently than SN-38. Although human lung cancer cells expressed hCE in the cytoplasm, hCE expression levels in cancer cells were not correlated with their drug sensitivities. Although intracellular CPT-11 and SN-38 levels continuously increased within 60 min of CPT-11 exposure, SN-38 levels in cells exposed to SN-38 decreased. Cells with the ability to metabolize SN-38 to SN-38G were more resistant to extracellular SN-38 than cells lacking the ability. Of 25 squamous cell carcinomas, 15 were strongly positive for hCE and six were negative. Of 25 adenocarcinomas, four were strongly positive for hCE and 16 were positive, while five were negative. Thus, 70% of non-small cell lung cancers expressed hCE. From these results, we conclude that human lung cancer cells expressed the enzyme which can convert CPT-11 to SN-38 and that intracellular SN-38 converted from CPT-11 may act as a chemotherapeutic agent together with SN-38 absorbed from the outside and augment the dose intensity of SN-38. Therefore, to assess the effects of CPT-11 prior to chemotherapy, it is important to check if lung cancer cells express hCE.

Central bronchopleural fistulas closed by bronchoscopic injection of absolute ethanol.

Five consecutive bronchopleural fistulas (BPFs) were successfully treated by injecting absolute ethanol directly into the submucosal layer of the fistula under flexible bronchoscopic observation. No complications occurred as a result of this treatment. Our nonsurgical treatment may be very useful to reduce the costs of and duration of hospitalization and to improve the patient's quality of life. This is the first report of the bronchoscopic closure of BPFs by injecting absolute ethanol, and we would recommend this treatment as a first-line therapy for patients with a postoperative central BPF with an orifice that is < 3 mm in diameter.