Increased expression of bcl-2 in drug-resistant squamous-cell lung carcinomas

The aim of this investigation was to prove whether or not an association exists between Bcl-2 expression and in vitro resistance to doxorubicin in biopsies of 85 human squamous cell lung carcinomas. Additionally, the relationship of Bcl-2 expression with resistance related proteins (P-glycoprotein, glutathione S-transferase-pi, catalase) was analyzed. Of the 85 carcinomas, 17 (20%) revealed Bcl-2 expression by immunohistochemistry. Seventeen of the tumors were classified as sensitive and 68 as resistant by an in vitro predictive test. All 17 Bcl-2-positive carcinomas were resistant to doxorubicin (p=0.018; chi(2)-test). A correlation was found between expression of Bcl-2 and expression of the resistance-related proteins P-glycoprotein and glutathione S-transferase-pi. The median survival time for patients with Bcl-2-negative carcinomas was two years and for Bcl-2-positive tumors over six years (log-rank test; p=0.08). Multivariate analysis (Cox regression model) revealed a borderline significant influence of Bcl-2 (p=0.07), whereas all other clinical factors (age, stage, metastasis) were of no significant influence on survival.

Up-regulation of heat shock protein 70 in adenocarcinomas of the lung in smokers

Tumour samples of smokers (n = 32) and non-smokers (n = 21) with previously untreated adenocarcinomas of the lung were analysed, immunohistochemically, for expression of the heat shock protein 70 (hsp70). A correlation between smoking habits and expression of hsp70 was found. Of the tumours from the 21 non-smokers 12 (57%) and of the 32 smokers 24 tumours (75%) showed high hsp70 expression. The expression of hsp70 depended on the number of cigarettes smoked daily. Of the patients who smoked more than 20 cigarettes, 16 out of 18 had tumours with a high hsp70 expression (89%; p = 0.028).

Expression of resistance-related proteins in nephroblastoma after chemotherapy

Tumor tissues of untreated and cytostatic-agent-treated patients with nephroblastomas were investigated for expression of resistance-related proteins (P-glycoprotein, glutathione S-transferase-pi, glutathione peroxidase and topoisomerase II) to ascertain whether resistance proteins are changed after treatment. Tumor tissue was analyzed by means of mRNA. Twenty-three children were treated with actinomycin D and vincristine for 4 to 8 weeks. Eight children received no preoperative chemotherapy. In untreated patients, no expression of P-glycoprotein was seen, whereas, in the patients who were treated with actinomycin D and vincristine, 12 out of 23 tumors showed increased P-glycoprotein expression (> mean value). Although we found no difference between treated and untreated tumors for glutathione S-transferase-pi, we found significant differences in the expression of glutathione peroxidase. In the 8 untreated patients, 7 tumors showed low glutathione peroxidase (< mean value) and one high (> mean value) glutathione-peroxidase-mRNA content. With treatment, 11 tumors expressed low levels and 12 tumors high levels of mRNA. A significant positive correlation between P-glycoprotein and glutathione peroxidase was found. In addition, of the 8 untreated patients, 2 had low topoisomerase-II expression, and 6 high expression. With treatment, the expression was reduced in 18 tumors, and only 5 tumors had high levels of this protein. These results were confirmed by PCR and immunohistochemistry.

Effects of single doses of irradiation on the expression of resistance-related proteins in murine NIH 3T3 and human lung carcinoma cells

In this report the effects of single doses of ionizing radiation on the mRNA expression of several proteins involved in multiple drug resistance were analyzed. Murine NIH 3T3 cells treated with single doses of 5, 10 and 20 Gy during the time interval from 1.5 to 72 h after irradiation were compared with their corresponding controls at the same points of time. The glutathione S-transferase-pi (GST pi) level was elevated in cells treated with 10 or 20 Gy from 24 to 72 h after irradiation compared with the control. Topoisomerase II alpha and thymidylate synthase were decreased in irradiated cells 24-72 h after exposure. These down-regulations were associated with cellular proliferation, determined by mRNA expression of the proliferation marker histone 3. Irradiated cells exhibited no alteration in the P-glycoprotein or glutathione peroxidase mRNA content. The finding that GST pi mRNA was overexpressed after irradiation was validated by investigations on a human lung carcinoma cell line (LXF 289) on the mRNA and protein level. Thus, our results indicate that irradiation alters the expression of proteins involved in multidrug resistance and may, therefore, play a role in clinical drug response.

Up-regulation of resistance-related proteins in human lung tumors with poor vascularization

Microvessel density was investigated by immunostaining endothelial cells for factor VIII antigen in 84 non-small cell lung carcinomas and compared with the expression of several resistance-related proteins. Glutathione S-transferase-pi, thymidylate synthase, metallothionein and, with limitations, P-glycoprotein were overexpressed in tumors with poor vascularization.

Heat shock (hsp70) and resistance proteins in non-small cell lung carcinomas

The aim of the study was to prove whether or not an association exists between the heat shock protein 70 (hsp70) and drug resistance. Tumor samples of 90 patients with previously untreated non-small lung carcinomas were investigated immunohistochemically for expression of resistance related proteins. Additionally, resistance to doxorubicin was determined using a short term test. No association between resistance related proteins. Additionally, resistance to doxorubicin was determined using a short term test. No association between resistance to doxorubicin and hsp70 was found. Of 63 resistant tumors, 33 showed low and 30 high hsp70 expression. Of the 26 sensitive tumors, 11 had low and 16 had high hsp70 expression. No relationship could be found between P-glycoprotein which is related to multidrug resistance and hsp70 expression or between hsp70 expression and expression of topoisomerase II, thymidylate synthase and metallothionein. On the other hand, a trend was noted for tumors with high glutathione S-transferase-pi expression to show high hsp70 expression. In addition, there was a significant relationship between hsp70 and catalase positivity. These data indicate that heat shock and stress promote intracellular oxidative damage and catalase is necessary for protection.

Predictive value of statin, a G0-associated cell cycle protein, in childhood acute lymphoblastic leukemia

Blast cells of 71 children with newly diagnosed acute lymphoblastic leukemia (ALL) were examined with a novel monoclonal antibody (MAb), S-44, immunoreactive to statin, a nuclear protein specifically expressed in non-proliferating cells. The statin labeling index (LI) varied greatly from case to case and ranged from 0.3% to 86%, with a mean value of 10%. The degree of statin LI correlated inversely with the expression of Ki-67. When patients were subdivided according to whether the statin LI was higher or lower than the mean value, patients with higher statin LI did not respond to chemotherapy and survived for a shorter period of time. Our results suggest that labeling of statin with the S-44 MAb is a useful prognostic marker of the cytotoxic effects of anti-cancer drugs in patients with ALL.

p53 protein detected by two different antibodies: relationship to proliferation and prognosis in acute lymphoblastic leukemia

The expression of p53 protein was examined in a series of 69 children with acute lymphoblastic leukemia with two different monoclonal antibodies (Mab 1801 and 240). p53 expression was detected with at least one antibody in 49 cases (71%), whereas only 19 cases (27%) were positive with both antibodies. Variability in the immunostaining could be observed depending on the antibody used. Mab 240 gave the highest rate of positive staining (58%), followed by 1801 with 39%. Positive staining with 1801 was significantly associated with decreased proliferation of tumor cells as measured by Ki-67 labelling, indicating that possibly the wild-type p53 protein is preferably stained with this antibody. However, neither of the two antibodies has prognostic value or is correlated with histopathological parameters.

Prognostic-significance of proliferating cell nuclear antigen (pcna) in adenocarcinoma of the lung

The aim of the study was to investigate the prognostic value of the proliferating cell nuclear antigen (PCNA) expression in non-small cell lung carcinomas (NSCLC). Two hundred and sixteen patients with previously untreated NSCLC entered into this investigation. For assessment of PCNA expression the streptavidin-biotinylated peroxidase complex method was performed using imnuunohistochemistry and Mab PC10. The tumors were scored for the percentage of PCNA-positive cells (low proliferative activity less than or equal to 25%; high proliferative activity >25%). Univariate analyses of all patients showed a trend that those with high proliferating tumors had shorter survival times than those with lower proliferating tumors. Similar results were obtained when the analysis was restricted to squamous cell carcinomas. Patients with adenocarcinomas and with high proliferating tumors had significantly shorter survival times than those with low proliferating tumors (p=0.028). No correlation was found between extent of tumors or metastasis and expression of PCNA. The multivariate analysis including age, sex, extent of tumors and metastasis as well as PCNA revealed a highly significant influence of extent of tumors (p=0.007) and metastasis (p=0.003) whereas all other factors including PCNA were of no significant influence.

Association of p53 expression with proliferative activity and poor-prognosis in patients with squamous-cell lung carcinomas

Tumor tissue of 65 patients with squamous cell lung carcinoma was analyzed for p53 expression using immunohistochemistry (DO-1) and for proliferative activity using flow cytometry. Of the 65 cases, 17 cases (26%) showed positive staining for p53, whereas 48 cases (74%) showed no expression. The median survival time for patients with p53-negative tumors was 100 weeks and for patients with p53-positive tumors 30 weeks (rank-sum test, p=0.03; log-rank test, p=0.14). The median survival time for patients with high proliferative activity (proportion of SG(2)M-phase cells >22%) was one year and for patients with low proliferative activity (proportion of SG(2)M-phase cells less than or equal to 22%) over 6 years (rank-sum test, p=0.04; log-rank test, p=0.01). There exists a trend that p53-positive squamous cell lung carcinoma had a higher proportion of SG(2)M-phase cells than p53-negative tumors. Multivariate analysis found independent prognostic significance for proliferative activity and stage but not for p53.

Modulation of doxorubicin-toxicity by tamoxifen in multidrug-resistant tumor cells in vitro and in vivo

Modulation of the resistance of tumors offers new strategies to improve the therapeutical treatment of cancer. In this report, the anti-oestrogen tamoxifen was investigated in multidrug-resistant tumor cells in vitro and in vivo. The doxorubicin-resistance of L 1210/DOX-tumor cells, which express the multidrug-resistance phenotype, could be completely circumvented by addition of 1 microgram/ml tamoxifen. In contrast, no increased effect could be observed in the parental L 1210 tumor cells or in cytosine arabinoside-resistant L 1210 cells not expressing the multidrug-resistance phenotype. Thus, the enhancing effect of tamoxifen was restricted only to the multidrug-resistant L 1210/DOX tumor cells. Similar to the in vitro experiments, a significant reduction in the growth in solid tumors of mice by the combined treatment of doxorubicin and tamoxifen was again observed only in the multidrug-resistant L 1210/DOX tumors.

Analysis of c-fos, c-jun, c-erbB1, c-erbB2 and c-myc in primary lung carcinomas and their lymph node metastases

The purpose of this study was to identify possible alterations in proto-oncogenes (c-fos, c-jun, c-erbB1, c-erbB2 and c-myc) at the protein level in primary lung carcinomas and simultaneous metastatic lymph nodes of 21 patients. The analysis showed that proteins of c-jun and c-myc were expressed in a significantly higher frequency in metastases than in primary lung tumors. Gross differences were not found between primary tumors and metastatic tumors with regard to the expression of c-erbB1, c-erbB2 and c-fos. The finding of cases with a higher expression of c-jun and c-myc in lymph nodes suggests that metastatic capability may be higher in certain cell populations.

Cytotoxic T lymphocytes with a grafted recognition specificity for ERBB2-expressing tumor cells

Experimental approaches which exploit the targeted cytolytic activity of lymphocytes are being developed for cancer therapy. We generated cytotoxic T lymphocytes (CTLs) with specificity for ERBB2 receptor-expressing tumor cells. A binding function was conferred directly on the zeta chain of the T-cell receptor (TCR) complex to circumvent major histocompatibility complex-restricted antigen recognition through the alpha and beta chains of the TCR. A chimeric gene was constructed which encoded a single-chain Fv antibody (scFv, consisting of the joined heavy- and light-chain variable domains of a monoclonal antibody against the extracellular domain of the ERBB2 receptor), a hinge region as a spacer, and the zeta chain of the TCR. This gene was introduced into CTLs by retroviral gene transfer. The signaling potential of the scFv/hinge/zeta receptors was demonstrated by secretion of interferon gamma upon coincubation with ERBB2-expressing cells. Target cells expressing the ERBB2 gene were lysed in vitro with high specificity by the scFv/hinge/zeta-expressing T cells. The growth of ERBB2-transformed cells in athymic nude mice was retarded by adoptively transferred scFv/hinge/zeta-expressing CTLs. Transduced CTLs labeled with a fluorescent dye were specifically detected in tumor sections. Our results suggest that tumor cell lysis by CTLs grafted in vitro with a major histocompatibility complex-independent recognition could become a gene-therapy approach to cancer treatment.

Detection of resistance proteins in matched primary lung tumors and lymph node metastases

The expression of several resistance markers (P-glycoprotein, glutathione S-transferase-pi, thymidylate synthase, dihydrofolate reductase) was analyzed in matched primary tumors and lymph node metastases from 21 patients with lung cancer using immunohistochemistry. The analysis showed that expression of these resistance proteins is generally congruent in primary lung cancer and simultaneously resected lymph node metastases. This suggests that in general the resistance of a primary tumor predicts for the resistance of the metastases and vice versa.

Cephalic-phase insulin in obese and normal-weight men: relation to postprandial insulin

Cephalic-phase insulin release (CPIR) and its relation to postprandial insulin release were examined in 18 normal-weight and 15 obese men. When the insulin data were expressed as absolute differences from baseline values, obese subjects exhibited significantly greater CPIR than normal-weight subjects (normals, 8.7 +/- 2.1 microU/mL/10 min; obese, 13.4 +/- 4.3 microU/mL/10 min; P < .01). Obese subjects were then separated into groups depending on their fasting insulin levels. This showed that only those subjects with elevated fasting insulin levels exhibited greater CPIR than normal subjects, and suggested that previous reports of exaggerated CPIR in the obese are merely a reflection of a basal hypersecretion of insulin. However, when insulin values were expressed as percentages of baseline, no significant differences between normal-weight and obese subjects were found, although a trend toward an attenuated response was observed in the obese group as a whole (normals, 81.6 +/- 19.1 microU/mL/10 min; obese, 51.3 +/- 16.1 microU/mL/10 min). A significant correlation between cephalic-phase and postprandial insulin release was found in normal-weight subjects (r = .62, P < .05), but not in obese subjects (r = .02, P < .9).

Correlation between successful heterotransplantation of lung tumors in nude mice, poor prognosis of patients and expression of Fos, Jun, ErbB1, and Ras

In order to examine whether the expression of the oncoproteins might be important for the malignancy of tumors, the relationship between the take rate of 88 human squamous cell lung carcinomas in nude mice and the expression of protooncogene products was analyzed. The expression of c-fos, c-jun, c-ras, c-erbB1, c-neu and c-myc at the protein level was investigated by immunohistochemistry. Tumor take was assumed if within three months growing nodules were detected and confirmed histologically. The take rate of squamous cell lung carcinomas in nude mice was 49%. Sixty-eight percent of the tumors were positive for Fos, 40% for Jun, 67% for Ras, 77% for ErbB1, 35% for Neu and 39% for Myc. Tumors with an (over)expression of the proteins encoded by the oncogenes c-fos, c-jun, c-erbB1 and c-ras had a significantly higher take rate in nude mice than tumors without an (over)expression of the oncogene products. In contrast, the expression of the c-neu and the c-myc genes at the protein level had no influence on the take rate of the tumors in nude mice. Interestingly, only patients with tumors with an (over)expression of the proteins encoded by the oncogenes c-fos, c-jun, c-erbB1 and c-ras had significantly shorter survival times than patients whose tumors did not show an (over) expression of the oncogene products. These results demonstrate that the aggressiveness of the tumors visible in the higher take rate of the tumors in nude mice and in the shorter survival times of patients can be detected by measurement of the expression of c-fos, c-jun, c-erbB1 and c-ras at the protein level.

Expression of resistance factors (P-glycoprotein, glutathione S-transferase-pi, and topoisomerase II) and their interrelationship to proto-oncogene products in renal cell carcinomas

BACKGROUND

This study investigates whether or not an interrelationship exists between the expression of resistance-related proteins (P-glycoprotein, glutathione S-transferase, topoisomerase II) and proto-oncogene products (c-fos, c-myc, c-K-ras, epidermal growth factor receptor [EGF-R], and c-neu proteins.)

METHODS

Thirty-eight human renal cell carcinomas of previously untreated patients were analyzed for expression of P-glycoprotein (P-170), glutathione S-transferase-pi (GST-pi), topoisomerase II (Topo II) and proto-oncogene proteins by means of immunohistochemistry. Because of significant heterogeneity in most tumor biopsies, all analyses were done on tumor-derived primary cell culture lines on the third or fourth passage.

RESULTS

An interrelationship between increased expression of P-170 and GST-pi and down-regulation of Topo II was found. Expression of the c-fos protein was seen in 66% of the tumors; expression of the c-myc protein, in 50%; of the c-K-ras protein, in 16%; of the EGF-R protein, in 61%; and of the c-neu protein, in 54% of the tumors. A significant correlation between the resistance factors and the c-fos, EGF-R, and c neu-proteins was observed (GST/c-fos, P = 0.012; Topo II/c-fos, P = 0.024; P-170/EGF-R, P < 0.001; GST/EGF-R, P = 0.018; Topo II/EGF-R, P = 0.027; P-170/c-neu, P = 0.005; GST/c-neu, P = 0.018; Topo II/EGF-R, P = 0.027; P-170/c-neu, P = 0.005; GST/c-neu, P = 0.008; Topo II/c-neu, P = 0.05). In contrast, interrelationships between resistance proteins and c-myc and c-K-ras proteins were not found. A significant interrelationship between the investigated resistance-related proteins or proto-oncogene proteins and the stage or grading of the tumors was not observed.

CONCLUSIONS

The results demonstrate that in renal cell carcinomas a significant relationship exists between resistance-related proteins, such as P-170, GST-pi, or Topo II, and proto-oncogenes, such as c-fos, c-erbB1, and c-neu.

Expression of resistance factors (P-glycoprotein, glutathione S-transferase-pi, and topoisomerase II) and their interrelationship to proto-oncogene products in renal cell carcinomas

BACKGROUND

This study investigates whether or not an interrelationship exists between the expression of resistance-related proteins (P-glycoprotein, glutathione S-transferase, topoisomerase II) and proto-oncogene products (c-fos, c-myc, c-K-ras, epidermal growth factor receptor [EGF-R], and c-neu proteins.)

METHODS

Thirty-eight human renal cell carcinomas of previously untreated patients were analyzed for expression of P-glycoprotein (P-170), glutathione S-transferase-pi (GST-pi), topoisomerase II (Topo II) and proto-oncogene proteins by means of immunohistochemistry. Because of significant heterogeneity in most tumor biopsies, all analyses were done on tumor-derived primary cell culture lines on the third or fourth passage.

RESULTS

An interrelationship between increased expression of P-170 and GST-pi and down-regulation of Topo II was found. Expression of the c-fos protein was seen in 66% of the tumors; expression of the c-myc protein, in 50%; of the c-K-ras protein, in 16%; of the EGF-R protein, in 61%; and of the c-neu protein, in 54% of the tumors. A significant correlation between the resistance factors and the c-fos, EGF-R, and c neu-proteins was observed (GST/c-fos, P = 0.012; Topo II/c-fos, P = 0.024; P-170/EGF-R, P < 0.001; GST/EGF-R, P = 0.018; Topo II/EGF-R, P = 0.027; P-170/c-neu, P = 0.005; GST/c-neu, P = 0.018; Topo II/EGF-R, P = 0.027; P-170/c-neu, P = 0.005; GST/c-neu, P = 0.008; Topo II/c-neu, P = 0.05). In contrast, interrelationships between resistance proteins and c-myc and c-K-ras proteins were not found. A significant interrelationship between the investigated resistance-related proteins or proto-oncogene proteins and the stage or grading of the tumors was not observed.

CONCLUSIONS

The results demonstrate that in renal cell carcinomas a significant relationship exists between resistance-related proteins, such as P-170, GST-pi, or Topo II, and proto-oncogenes, such as c-fos, c-erbB1, and c-neu.

High rate of expression of multidrug resistance-associated P-glycoprotein in human endometrial carcinoma and normal endometrial tissue

The overexpression of P-glycoprotein was studied in 10 normal endometrial controls (five from the proliferative and five from the secretory phase of the menstrual cycle) and in 23 endometrial carcinomas of different histological varieties, using the C219 and JSB-1 monoclonal antibodies. Three of the tumours had been previously treated with combination chemotherapy containing doxorubicin. All endometrial carcinomas, whether treated or untreated, as well as the normal endometrial controls from both the proliferative and the secretory phase of the menstrual cycle, overexpressed P-glycoprotein. This puts endometrial carcinoma into the same category as other tumours arising in organs which normally overexpress P-glycoprotein, all of which tend to be intrinsically resistant to chemotherapy.

Elevated expression of thymidylate synthase in doxorubicin resistant human non small cell lung carcinomas

Human non-small cell lung carcinomas of previously untreated patients were analyzed for expression of thymidylate synthase (TS) using immunohistochemistry. Of the 94 tumors, 67 were positive for TS and 27 negative. A significant correlation between the expression of TS and the resistance to doxorubicin was found (p < 0.0001). Eighty-four percent of the TS-positive tumors were resistant to doxorubicin, whereas of the 27 TS-negative tumors only 44 percent were resistant. A group of patients (n = 13) were treated with combination chemotherapy including 5-fluorouracil, doxorubicin and cisplatinum. Seven of the 8 tumors which were TS-positive were clinically progressive, whereas 4 of 5 tumors which were TS-negative showed clinical remission after chemotherapy (p < 0.05; Fisher exact test). The patients whose tumors were TS negative lived significantly longer than those with TS-positive tumors. The median survival times were 185 weeks for patients with TS-negative and 41 weeks for patients with TS-positive tumors (p < 0.05; log-rank-test). Thus the expression of TS is a strong prognostic factor for resistance of tumors, clinical course and survival of patients with non-small cell lung carcinomas.

Expression of topoisomerase II, catalase, metallothionein and thymidylate-synthase in human squamous cell lung carcinomas and their correlation with doxorubicin resistance and with patients' smoking habits

Forty-eight human squamous cell lung carcinomas of previously untreated patients were analyzed for resistance to doxorubicin and for the presence of topoisomerase II (Topo II), metallothionein (MT), thymidylate synthase (TS) and catalase (Cat). Significant correlations exist between resistance to doxorubicin measured by the in vitro short-term test and overexpression of MT and TS measured by immunohistochemistry. No significant correlation was found between resistance and expression of Topo II or Cat. No significant interrelationship between smoking habits of patients and expression of Topo II, MT, TS or Cat was found.

Relationship of inherent resistance to doxorubicin, proliferative activity and expression of P-glycoprotein 170, and glutathione S-transferase-pi in human lung tumors

BACKGROUND

This study analyzed whether proliferative activity and expression of P-glycoprotein 170 (P-170) or glutathione S-transferase-pi (GST-pi) in human non-small cell lung carcinomas (NSCLC) represent independent factors in resistance to doxorubicin or whether an association exists between these factors.

METHODS

Thirty-six patients with previously untreated NSCLC participated in the study. The thymidine labelling index (TLI) was measured for detection of proliferative activity, and immunohistochemistry was used for detection of P-170 and GST-pi. The resistance of tumors was determined in vitro by the nucleotide incorporation assay.

RESULTS

Negative correlations between TLI and P-170 (P = 0.0009) or GST-pi (P = 0.007) were found. Positive correlations existed between resistance to doxorubicin in vitro and P-170 (P = 0.005) or GST-pi (P less than 0.0001). Expression of P-170 and GST-pi showed highly significant (P less than 0.0001) positive correlation.

CONCLUSIONS

The results demonstrate that a significant positive relationship between P-170 and GST-pi in NSCLC exists and that the expression is increased in resistant tumors and in tumors with a low proliferative activity.