Gains and losses of DNA sequences in malignant mesothelioma by comparative genomic hybridization

The molecular basis of malignant mesothelioma is poorly known. We examined genetic changes in 11 mesothelioma specimens by comparative genomic hybridization (CGH). Five DNA specimens originated from uncultured tumor tissues and six from cell lines established from the same patients. Findings from the classical karyotypic characterization of both primary tumors and cell lines have been reported previously. In the CGH analyses the most common genetic alterations in the 11 mesothelioma specimens were losses of chromosomal regions in 1p, 8p, 14q, and 22q and gains of 5p, 6p, 8q, 15q, 17q, and 20. The cell lines had on average a much higher total number of genetic changes than the uncultured tumor specimens. Clonal relationship between the cell lines and the uncultured tissue specimens could not usually be demonstrated even though they originated from the same patient. The observed differences may partly be due to high frequency of chromosomal rearrangements, which CGH cannot detect, partly due to contamination of tumor specimens with normal tissue, and partly due to genetic evolution in tumor cell lines.

Activity of gemcitabine in patients with non-small cell lung cancer: a multicentre, extended phase II study

Gemcitabine is a novel nucleoside analogue with activity in solid tumours. This study assessed the objective response rate to gemcitabine given weekly intravenously at a dose of 1250 mg/m2 for 3 weeks followed by 1 week of rest (one cycle) in chemonaive patients with inoperable non-small cell lung cancer (NSCLC). 161 patients with NSCLC were recruited from 10 sites in nine countries. Most patients had stage IIIb (31.3%) or IV (64.6%) disease, and 93.8% had a performance status of 0 or 1 according to the WHO scale. Of 151 evaluable patients, there were 3 complete responses and 30 partial responses lasting at least 4 weeks for an objective response rate of 21.8% (95% CI 15.5-29.3%). All responses were validated by an extramural Oncology Review Board. The mean duration of response was 8.8 months. The mean survival for all patients (16.1% of patients still alive 26 months after last patient started treatment) was 11.5 months. Improvements were also observed in secondary efficacy parameters such as performance status, weight, analgesic requirement, pain, and other disease-related symptoms including cough, dyspnoea, haemoptysis, anorexia, somnolence and hoarseness. Haematological and non-haematological toxicity was mild given the biological activity of gemcitabine. This study confirms gemcitabine as one of the most active agents in NSCLC with the added benefit of a modest toxicity profile and ease of administration on an out-patient basis. Gemcitabine is a suitable candidate for combination chemotherapy in patients with NSCLC.

Radiosensitivity of mesothelioma cell lines

The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters alpha and beta of the linear quadratic model (LQ-model) and mean inactivation dose (D(MID)) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean alpha value was 0.26 (range 0.48 - 0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The alpha/beta ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h.

Manganese superoxide dismutase in human pleural mesothelioma cell lines

Mesothelioma is a malignant pleural or intraperitoneal tumor attributable to asbestos exposure in more than 80% of the cases. Manganese superoxide dismutase (MnSOD), a mitochondrial superoxide radical scavenging enzyme, is low in most tumors but is known to be induced by asbestos fibers and certain cytokines. Induction of MnSOD may be associated in asbestos-related pulmonary diseases in vivo. We investigated here MnSOD specific activity and MnSOD mRNA level using healthy human lung tissue, SV40-transformed human pleural mesothelial cells (Met5A), and six human malignant mesothelioma cell line cells. Total SOD (CuZnSOD + MnSOD) and MnSOD activities were 20.0 +/- 4.8 U/mg protein and 3.2 +/- 1.2 U/mg protein in healthy human lung tissue, and 25.6 +/- 10.7 U/mg and 3.8 +/- 1.0 U/mg in Met5A cells, respectively. In four mesothelioma cell lines MnSOD activity was significantly elevated, the highest activity (30.1 +/- 8.2 U/mg) was almost 10-fold compared to the activity in Met5A cells. The steady state mRNA level of MnSOD was low in Met5A cells and markedly higher in all mesothelioma cell lines roughly in proportion with enzyme activities. Cytotoxicity experiments, which were conducted in four cell lines, indicated that cells containing high MnSOD mRNA level and activity were resistant to the mitochondrial superoxide-producing agent menadione. In conclusion, our results suggest that human mesothelioma may express high levels of MnSOD, which is associated with high oxidant resistance of these cells.

Inherited GSTM1 and NAT2 defects as concurrent risk modifiers in asbestos-related human malignant mesothelioma

Besides asbestos exposure, the factors that determine susceptibility to malignant mesothelioma are unknown. We evaluated the risk of GSTM1 null genotype and slow acetylation-associated NAT2 genotype for malignant mesothelioma in relation to asbestos exposure. Both the GSTM1 null genotype and the NAT2 slow acetylator genotype placed individuals at about 2-fold increased risk of developing malignant mesothelioma [odds ratio (OR) = 1.8, 95% confidence interval (CI) = 1.0-3.5 and OR = 2.1, 95% CI = 1.1-4.1, for the GSTM1 and NAT2 genes, respectively]. When the patients were divided into low/moderate and high exposure groups according to their asbestos exposure histories, the effect of the at-risk genotypes was mostly attributable to the high exposure groups (OR = 2.3, 95% CI = 1.0-5.6 and OR = 3.7, 95% CI = 1.3-10.2, for the GSTM1 and NAT2 genes, respectively). The individuals with combined GSTM1 and NAT2 defects had about a 4-fold risk of developing malignant mesothelioma compared to those with the GSTM1 gene and NAT2 fast acetylator genotype (OR = 3.6; 95% CI = 1.3-9.6). Moreover, the risk among subjects highly exposed to asbestos with the double at-risk genotype was more than 7-fold greater compared to those with the more beneficial genotypes of both GSTM1 and NAT2 genes (OR = 7.4; 95% CI = 1.6-34.0).

Evaluation of the clinical TNM staging system for malignant pleural mesothelioma: an assessment in 88 patients

There is no universally-recognised method for staging malignant mesothelioma, although the use of computed tomograph (CT) scanning has improved the staging of non-invasive disease. The International Union against Cancer has recently proposed using the Tumour Node Metastases (TNM) staging system for mesothelioma, but in clinical practice it is difficult to assess tumour and nodal involvement due to the unique plate-like growth pattern of this tumour. In order to evaluate TNM staging we analysed pre-operative CT scans from 88 patients with histologically-confirmed malignant pleural mesothelioma, all from the same institution. The median age of the patients was 56 years (range 38-79). There were 70 men and 18 women, and 33 had tumours with epithelial histology. The median survival time was 10 months (range 0.2-110), from the date of histological confirmation of mesothelioma. The same radiologist analysed all the CT scans according to the TNM staging system. Actuarial survival curves were constructed by the Kaplan-Meier method. Survival curves for the different TNM categories were compared using the log-rank test. Node evaluation could not be completed in eight cases because the tumour had encompassed the hilum and mediastinum. In multivariate analysis, significant differences in prognosis correlated with the different T categories (P < 0.01), and the different TNM stages (P < 0.05), but not the N categories or the M categories. Larger studies are needed to assess the importance of TNM staging in the selection of treatment and as a prognostic factor for malignant mesothelioma.

Interferon (IFN)-alpha and IFN-gamma in combination with methotrexate: in vitro sensitivity studies in four human mesothelioma cell lines

Mesothelioma is a malignant tumor of the serous surfaces in the thorax and abdomen, which has proved exceptionally resistant to treatment. A recent phase II trial of a high-dose methotrexate regime on 63 Norwegian patients has, however, achieved a response rate of 37%. Some responses have also been achieved using interferon (IFN)-gamma administered intrapleurally or recombinant (r) IFN-alpha administered subcutaneously. Our earlier in vitro sensitivity studies of mesothelioma cell lines showed that IFN augments the response to chemotherapeutic agents in mesothelioma. The aim of this study was to assess the response of four mesothelioma cell lines, derived from diffuse asbestos-related pleural malignant mesothelioma, to methotrexate alone and in combination with recombinant IFN-alpha and IFN-gamma. Anti-proliferative effects were assayed by vital dye exclusion. A combination of IFN-alpha and IFN-gamma consistently augmented the response of the cell lines to methotrexate, by as much as 75% for one cell line, although the response to the individual IFNs was variable. We were also able to compare the effects of natural IFN-beta with those of IFN-alpha and IFN-gamma. The IFN-beta sensitivity profile for each of the four cell lines was similar to that of IFN-alpha. In two cell lines, the combination of IFN-beta and IFN-gamma produced a similar effect to the IFN-alpha and IFN-gamma combination.

Inhaled recombinant interferon gamma in patients with lung cancer: pharmacokinetics and effects on chemiluminescence responses of alveolar macrophages and peripheral blood neutrophils and monocytes

PURPOSE

A Phase I trial was conducted to investigate clinical toxicity, pharmacokinetics, and chemiluminescence (CL) responses of alveolar macrophages (AM) and peripheral blood neutrophils and monocytes after inhalation of recombinant interferon (r IFN)-gamma.

METHODS AND MATERIALS

Eight patients with lung cancer inhaled r IFN-gamma as single doses of 0.1, 0.2, 0.6, 1.8, or 5.4 mg. Bronchoalveolar lavage was performed three times, 21 h before as well as 3 and 27 h after inhalation.

RESULTS

Interferon-gamma was detectable in bronchoalveolar lavage fluid (BALF) samples taken 3 h after inhalation in doses of > or = 0.6 mg. Before inhalation, AM in four out of seven patients studied showed vigorous lucigenin-enhanced CL responses to N-formyl-methionyl-leucyl-phenylalanine and opsonized zymosan particles. Furthermore, the responses were markedly increased 3 h after inhalation. In three out of seven patients, AM in the pretreatment BALF samples showed low or no CL responses, and the responses did not increase after inhalation of IFN-gamma, suggesting that the patients were anergic. Postinhalation CL responses did not correlate with the dose of IFN-gamma inhaled. Circulating IFN-gamma was detected in one patient receiving the highest dose. No changes referable to IFN-gamma inhalation were found in the CL responses of blood neutrophils and monocytes. During the 24 h follow-up, two patients developed transient fever-reactions.

CONCLUSIONS

The findings suggest that inhalation may provide a way to increase alveolar concentrations of IFN-gamma and to augment respiratory burst capacity of AM without any major side effects. This approach may have clinical implications for the treatment of tumors and infections of the respiratory tract.

Absence of trisomy 7 in nonneoplastic human ascitic and pleural fluid cells. An interphase cytogenetic study

Trisomy 7 is a frequent aneuploid change in lymphomas, adenocarcinomas, and malignant mesenchymal and neurogenic tumors. Moreover, it has been observed in cultured and uncultured non-neoplastic cells from brain, kidney, liver, lung, and atherosclerotic plaques, among other tissues, opening debate on the role of this change in normal and neoplastic tissue. We used nonradioactive in situ hybridization (ISH) with a biotinylated chromosome 7-specific alpha-satellite DNA probe to seek an extra copy of chromosome 7 in ascitic and pleural fluid interphase cells from 26 donors. The donors comprised 24 patients with nonmalignant clinical history, one patient with non-Hodgkin's malignant lymphoma (positive control), and one patient with chronic myeloid leukemia (CML, negative control). The highest frequency of fluid cells with three hybridization signals in patients without neoplasia was 0.5%, in contrast to the frequency of 40.5% noted in the fluid cells of the patient with non-Hodgkin's malignant lymphoma. The results demonstrate that the frequency of trisomic cells in pleural as well as in ascitic fluid is very low, making possible use of the cells in ascitic or pleural fluids in identification of malignancy.

Subcutaneously administered recombinant interferon-gamma in humans: pharmacokinetics and effects on chemiluminescence responses of alveolar macrophages, blood neutrophils, and monocytes

A Phase I trial was conducted to investigate the clinical toxicity, pharmacokinetics, and chemiluminescence (CL) responses of alveolar macrophages (AMs), peripheral blood neutrophils, and monocytes after subcutaneous injection of recombinant interferon-gamma (rIFN-gamma). Six patients with lung cancer received rIFN-gamma subcutaneously as single doses of 0.2, 0.6, and 1.8 mg. Bronchoalveolar lavage was performed three times: 21 h before as well as 6-7 and 27 h after injection. Serum samples were taken five times during the 27-h follow-up. IFN concentrations were measured from alveolar epithelial lining fluid (ELF) and serum by using an antiviral bioassay. IFN-gamma was not detectable in ELF after subcutaneous injection. AMs did not effect an increase in CL responses to N-formyl-methionyl-leucyl-phenylalanine or to phosphate-buffered saline. Circulating IFN-gamma was detectable at 3-12 h after an injection of 1.8 mg of rIFN-gamma, the highest dose given. CL responses of peripheral blood monocytes increased in all patients after injection, whereas the responses of neutrophils were less clear-cut. All patients developed systemic side effects such as transient fever, nausea, headaches, and flu-like symptoms. The findings suggest that rIFN-gamma passes poorly from the blood to the pulmonary alveoli. On the basis of this and our previous findings of increased CL responses in AMs and measurable IFN concentrations in ELF after inhalation of rIFN-gamma, we recommend inhalation rather than the parenteral route of IFN-gamma for the treatment of respiratory diseases.

Pharmacokinetics and toxicity of inhaled human natural interferon-beta in patients with lung cancer

Eight patients with a thoracic malignancy inhaled single doses of 3-100 x 10(6) IU of human natural interferon (IFN)-beta via a dosimeter-equipped jet nebulizer. After inhalation IFN-beta was not detectable in any of the serum samples as measured using an antiviral bioassay. Except for a slight body temperature rise and an 18% decrease in peak expiratory flow rate observed in 1 patient the patients did not experience any major side effects. Inhaled natural IFN-beta in this study was tolerated better than inhaled IFN-alpha or IFN-gamma in our previous studies. IFN-beta might thus be a promising local treatment for pulmonary diseases. Further work is needed to investigate the concentrations of biologically active IFN in alveolar epithelial lining fluid after inhalation and the therapeutic effect of inhaled IFN-beta.

Immunological evidence for co-expression of cluster-5 and cluster-5A small cell lung cancer antigen on a single molecule

We have investigated immunologically the molecular association of the cell-surface sialoglycoprotein antigens cluster-5 (CL-5) and cluster-5A (CL-5A), known to be co-expressed in human small-cell lung cancer (SCLC). CL-5 antigen is exclusively defined by IgM antibodies as represented by MAb LAM8, whereas CL-5A antigen is exclusively defined by IgG antibodies as represented by MAbs SWA20 and SEN31. Because of the unavailability of purified antigens, the question of the molecular relationship between these antigens was addressed by immunological studies. We generated an anti-anti-idiotypic MAb of the IgG isotype using a CL-5-antigen-mimicking anti-idiotype defined by rat MAb Ly8-229 as an immunogen to circumvent the avidity problems observed with the IgM MAb LAM8 in binding-competition experiments. In addition, we developed a heterologous double antibody sandwich assay able to identify circulating CL-5/5A antigens in pre-treatment sera of patients with SCLC. The results of both types of immunological studies demonstrated the expression of CL-5 and CL-5A antigens on a single molecule, both in cellular assays and in assays detecting antigens shed into the serum of patients with SCLC.

Interferon-alpha and interferon-gamma combined with chemotherapy: in vitro sensitivity studies in non-small cell lung cancer cell lines

Non-small cell lung cancers (NSCLC) are often resistant to chemotherapy. Cisplatin has shown the most activity against all the histological subtypes and is now used in most combined treatment programmes. Interferon (IFN)-alpha has been shown to potentiate cisplatin and other drugs experimentally and in clinical trials involving NSCLC. We are looking at the responses of different NSCLC cell lines to cisplatin (P), etoposide (VP-16) and IFN [recombinant human IFN-alpha 2c (IFN-alpha) and IFN-gamma 1b (IFN-gamma)], individually and in combination. We then compare the results with those from a clinical trial of etoposide and cisplatin with interferon in advanced NSCLC. We report here the results from the first of our cell lines, established from a large cell anaplastic carcinoma. We have confirmed earlier findings that NSCLC cell lines are not sensitive to either IFN-alpha or IFN-gamma alone. However a combination of IFN-alpha and IFN-gamma does reduce cell proliferation in our cell lines. This IFN combination potentiates the response of the cells to etoposide far more than to cisplatin. There is a trend towards greater activity when a combination of cisplatin and etoposide is used, compared with the activity of either drug alone. This effect is further increased by the interferon combination.

Bronchoalveolar lavage fluid findings following radiotherapy for non-small cell lung cancer

PURPOSE

To evaluate the diagnostic potential of bronchoalveolar lavage fluid analysis in radiation-induced lung injury.

METHODS AND MATERIALS

Thirty patients with inoperable non-small cell lung cancer received either high-dose hyperfractionated radiotherapy or radiotherapy and interferon, a potential radiosensitizer, or radiotherapy and N-acetylcysteine, a potential radioprotector. Bronchoalveolar lavages were performed before and immediately after radiotherapy, and thereafter 6-8 weeks and 3 months after radiotherapy. Total and differential cell counts were measured from the bronchoalveolar lavage fluid samples. Urea measured in serum and in bronchoalveolar lavage fluid was used to calculate epithelial lining fluid. The concentrations of protein and phosphatidylcholine, the major surfactant phospholipid, in epithelial lining fluid were measured. The extent of radiation-induced lung injury was assessed from computed tomographies performed before radiotherapy, and 6-8 weeks and 3 months after radiotherapy.

RESULTS

More patients in the interferon-arm developed radiation pneumonitis than did patients in the other groups, but no significant differences in alveolar fluid indices were noted between the groups. When all the patients were studied together, radiation was shown to have induced a significant relative increase of lymphocytes in bronchoalveolar lavage fluid 6-8 weeks and 3 months after the end of radiotherapy. The concentration of phosphatidylcholine in epithelial lining fluid decreased significantly 6-8 weeks and 3 months after treatment. The increase in protein concentration in epithelial lining fluid reached a statistically significant level 6-8 weeks after radiotherapy.

CONCLUSION

Analysis of bronchoalveolar lavage fluid predicts the degree of radiation pneumonitis; however, radiology remains to be "the gold standard."

Adjuvant chemotherapy after radical surgery for non-small-cell lung cancer: a randomized study

PURPOSE

The aims of this study were to assess the effect of adjuvant chemotherapy on overall survival, disease-free survival, and relapse pattern, as well as its toxicity in patients who underwent radical surgery for non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

One hundred ten patients with T1-3N0 (World Health Organization [WHO] 1981) NSCLC underwent radical surgery during the period of 1982 through 1987. After surgery, the patients were randomized to receive adjuvant chemotherapy (n = 54) (cyclophosphamide 400 mg/m2, doxorubicin 40 mg/m2, and cisplatin 40 mg/m2 [CAP] for six cycles) or no active treatment (n = 56).

RESULTS

After 10 years from the start of the study, 61% of patients were alive in the chemotherapy group and 48% were alive in the control group (P = .050). Seventeen patients (31%) in the CAP group and 27 patients (48%) in the control group had a recurrence during the follow-up period (P = .01). The 5-year survival rate was 67% in the chemotherapy group and was 56% in the control group (P = .050). The patients in the chemotherapy group who completed the planned treatment had a slightly better 5-year survival than those whose chemotherapy was discontinued (72.5% v 50.3%; P = .15). Chemotherapy-related gastrointestinal toxicity grade 3 to 4 (WHO) occurred in 63% and was the main reason why patients refused further planned therapy.

CONCLUSION

Our results suggest that patients with NSCLC at pathologic stage I who have undergone radical surgery benefit from adjuvant chemotherapy.

Interferon-alpha and -gamma in combination with chemotherapeutic drugs: in vitro sensitivity studies in four human mesothelioma cell lines

Mesothelioma is a tumor of the serous surfaces in the thorax and abdomen. This tumor has proved to be exceptionally resistant to treatment, although a variety of multi-modality therapies have been tried. We have used four human mesothelioma cell lines, originating from diffuse asbestos-related malignant (pleural) mesothelioma, to assess in vitro sensitivity to five chemotherapeutic drugs, to recombinant human interferon (IFN)-alpha and -gamma and to combined immuno-chemotherapy. The cytotoxic effects were assayed by vital dye exclusion. The drugs tested were etoposide, cisplatin, mitoxantrone, 4-epirubicin and vindesine. The combinations tested were etoposide+cisplatin, and etoposide+cisplatin+mitoxantrone. All the drugs and combinations were also tested with recombinant human (rHu) IFN-alpha 2C (rHuIFN-alpha), rHuIFN-gamma, and rHuIFN-alpha+rHuIFN-gamma. The cell lines were most sensitive to mitoxantrone, 4-epirubicin and vindesine (TC50 < or = 0.001 micrograms/ml), and least sensitive to etoposide and cisplatin (TC50 > or = 0.1 micrograms/ml) used singly. There was no improvement in sensitivity when the drugs were combined. To further investigate the lack of response to cisplatin treatment, we examined the binding of cisplatin to the mesothelioma cell DNA. The tumor cell DNA bound markedly less cisplatin than human fetal fibroblast DNA. Three cell lines were tested with rHuIFN-alpha and rHuIFN-gamma on their own or rHuIFN-alpha+rHuIFN-gamma. They were consistently sensitive to rHuIFN-alpha, but the sensitivity to rHuIFN-gamma varied with the cell lines. Finally, we tested two cell lines with the drugs singly and in combination, together with 0.01 micrograms/ml each of rHuIFN-alpha and rHuIFN-gamma.(ABSTRACT TRUNCATED AT 250 WORDS)

N-acetylcysteine in combination with radiotherapy in the treatment of non-small cell lung cancer: a feasibility study

N-Acetylcysteine (NAC) is a free radical scavenger and could therefore act as a radioprotector. To test the feasibility of administering NAC in combination with radiotherapy, we studied 10 patients with inoperable non-small cell lung cancer who were receiving hyperfractionated radiotherapy (RT) of 1.25 Gy B.I.D. (6-h interval) up to a total dose of 60 Gy/48 fractions/32 days. They were given NAC concomitantly with RT: 100 mg/kg i.v. 30 min before the first RT session followed by 30 mg/kg as an i.v. infusion over 7 h; and 600 mg inhaled 30 min before and after each RT session. The patients were assessed by serial CT scans and lung function studies during a 1-year follow-up period. The treatment regime was feasible, but expensive in time and resources. Normal tissue reactions and tumour responses were similar to those in a control group.