Two-stage operative cytoreduction and intraperitoneal chemotherapy for diffuse malignant peritoneal mesothelioma: Operative morbidity and mortality in phase I and II trials

AIMS

The standard of care for diffuse malignant peritoneal mesothelioma involves operative cytoreduction and intraperitoneal chemotherapy. Most centers favor aggressive operative cytoreduction, accepting high morbidity and mortality. In our trials, patients underwent less extensive cytoreduction followed by prolonged intraperitoneal chemotherapy. Patients underwent a second cytoreduction with heated intraperitoneal chemotherapy. We hypothesized this would result in lower operative morbidity and mortality with similar survival.

METHODS

Hospital records, discharge summaries, microbiology, radiography, and office records were retrospectively reviewed to supplement a prospective database. 30-day morbidity and mortality were categorized, and classified according to the Clavien methodology.

RESULTS

47 first and 39 second operations were performed with 13% and 26% morbidity, respectively. Mortality was 2%. Infections comprised 59% of the morbidity. Inclusive of both operations, formal peritonectomy was performed in 16% of patients, resection of isolated lesions in less than half, and only 19% had a visceral organs other than the spleen resected. At the completion of the protocol, only 3% of patients had visible intraperitoneal disease. The mean total length of stay for both operations combined was 16 ± 23 days. Overall median survival was 54.9 months, and median survival for the epithelioid subtype was 70.2 months.

CONCLUSIONS

A two-stage cytoreduction with intraperitoneal chemotherapy offers median survival comparable to one-stage protocols, with relatively low morbidity, mortality, visceral resections and length of stay despite two operations. This series supports that our protocol is a feasible and safe approach.

Influence of microscopic malignant peritoneal mesothelioma on posttreatment survival

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Background: Progression of malignant peritoneal mesothelioma to clinically evident disease is poorly understood. Operative cytoreduction and post-operative intraperitoneal chemotherapy, followed by a second operative cytoreduction with heated intraoperative intraperitoneal chemotherapy is protocol at Columbia University. Our ability to assess presence of microscopic disease at a unique second operation provides in vivo insight into disease progression. Methods: Operative, pathology and oncologist records were reviewed for 98 consecutive patients with peritoneal mesothelioma treated between 5/95 and 1/08. Microscopic disease was defined as positive pathology on random biopsies in the absence of gross disease at second operation, and disease-free as absence of gross and microscopic disease. Survival was defined as time from first operation to death or last follow-up. Survival and recurrence were compared using the Kaplan Meier and log-rank methods, and correlations by Fisher's exact method. Results: 98 first and 69 second operations were performed. Patients were 59% male, 88% Caucasian and mean age was 52. At the second operation, 38 had gross disease, 23 were disease-free and 8 had microscopic disease. Median follow-up was 21 months, median overall survival was 48 months, and median survival for the epithelial subtype was 64 months. There was no significant difference in survival between disease- free and microscopic pathologies (log-rank p<0.69). 72% of disease-free (SE 11%) and 80% (SE 18%) of those with microscopic disease were alive at 96 months. 16% of disease-free and 7% of patients with microscopic disease had a recurrence (p<0.4). The time to clinical recurrence for both disease-free and microscopic disease was not significantly different (log-rank p<0.88). Conclusions: Survival and clinical recurrence in those with microscopic disease, none of whom were treated for this entity, were not significantly different from those who were disease-free at the second operation. These in vivo after treatment findings suggest that malignant peritoneal mesothelioma may progress slowly from microscopic to clinical disease and can be closely monitored rather than aggressively treated after initial cytoreduction and intraperitoneal chemotherapy.

No significant financial relationships to disclose.

Use of laser capture microdissection to derive poor prognosis gene expression signatures of epithelial abdominal malignant mesothelioma

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Background: Prior work in abdominal malignant mesothelioma (AMM) has established a poor prognosis profile of biphasic AMM when compared to more favorable prognosis epithelial AMM. It is evident, however, that epithelial AMM shows heterogeneity in biologic behavior and prognosis. Given improvements in therapy and survival in AMM, stratification of patients with epithelial AMM into favorable and poor prognosis subgroups is desirable and gene expression profiles may provide poor prognosis signatures to further guide therapy. Methods: Favorable and poor prognosis subgroups were defined as 1000 days of survival time (based on median survival of 90 patients with AMM at Columbia Presbyterian as of Sept 2007). Fourteen frozen epithelial AMM (7 favorable prognosis, 7 poor prognosis) with high quality RNA were laser capture microdissected using a PALM Zeiss microscope and analyzed using Affymetrix U133 Plus 2 microarrays. Unsupervised hierarchical clustering and supervised subgroup analysis were performed using BRB tools version 3.2. Results: Unsupervised hierarchical clustering revealed 2 main clades that contained 6 of 7 poor prognosis and 6 of 7 favorable prognosis tumors, respectively. Supervised class comparison revealed a 39-gene signature that distinguished the 2 classes (permutation values of p < .001). High expression of Nde1, UHRF1, and EZH2 by qPCR on a set of 32 AMM (using an upper quartile cutoff) was associated with poor survival (Log rank statistic p<.01, p<.003 and p<.03 respectively). Immunohistochemistry performed on tissue microarrays of 122 AMM for p16 loss and increased EZH2, Col3A1 and UHRF1 immunoreactivity was associated with poor survival (Log rank statistic p<.0001, p<.009, p<.0001 and p<.012, respectively). Conclusions: Using a training set of laser captured favorable and poor prognosis epithelial AMM, a 39-gene signature was obtained that is associated with prognosis. Validation of several of the candidate genes by qPCR expression and immunohistochemistry was performed, confirming favorable and poor prognosis strata among the epithelial AMM. Identification of poor prognosis epithelial AMM at the time of initial biopsy/tumor cytoreduction could lead to more aggressive primary therapeutic intervention.

No significant financial relationships to disclose.

18FDG-PET in the management of malignant peritoneal mesothelioma: A retrospective review of 145 scans in 37 patients

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Background: Malignant peritoneal mesothelioma is a rare tumor best managed by an interdisciplinary approach. The role of 18FDG-PET scans in monitoring patients with peritoneal mesothelioma has not been defined. Methods: Patients with peritoneal mesothelioma treated at Columbia University (October, 1997 - October, 2006) who had a PET scan were reviewed. Data were gathered on modes of therapy, imaging, and clinical outcome. The frequency with which PET scans led to a change in management, defined as scans that led to a biopsy or initiation of chemotherapy, was evaluated. Results: 37 patients, 21 women (57%) and 16 men (43%), were reviewed. The median age was 50 (range 14 - 79) years. All patients underwent surgery, 35 (95%) intraperitoneal chemotherapy, 15 (41%) external beam radiation, and 17 (46%) intravenous chemotherapy. At 43 (range 8.5 - 127) months median follow-up, 27 (73 %) are alive. Among 145 PET scans, 66 (46%) were PET/CT scans, 52 (26%) were PET scans with a CT scan performed within one month, and 27 (19%) were PET scans only. 8 (6%) of PET scans were for initial staging, and 137 (95%) for monitoring. A change in management based on findings in PET imaging occurred in 11 (30%) patients and 14 (10%) scans. Two patients were started on salvage chemotherapy without further evaluation. Two were diagnosed with peritoneal recurrence, 1 with lung metastasis, 1 with lymph node metastasis, 1 with a second malignancy, and 3 with colon polyps. One had a false positive scan, proven by negative surgical biopsy. PET provided early detection of disease progression in 6 (16%) of patients evaluated. One patient (3%) had biopsy proven progressive disease despite no 18FDG uptake on PET scan. Conclusions: 18FDG-PET findings changed management in 30% of patients with peritoneal mesothelioma undergoing multimodality therapy, and provided early detection of recurrence in 16% of patients. Further evaluation of test characteristics and prognostic value of 18FDG-PET in the setting of peritoneal mesothelioma is warranted.

No significant financial relationships to disclose.

Molecular profiling of malignant peritoneal mesothelioma identifies the ubiquitin–proteasome pathway as a therapeutic target in poor prognosis tumors

Malignant mesothelioma is an aggressive neoplastic proliferation derived from cells lining serosal membranes. The biological and clinical characteristics of epithelial type malignant mesothelioma are distinct from those of biphasic and sarcomatous type tumors. The goal of our study was to examine the molecular basis for this distinction. Microarray analysis confirmed that the molecular signatures of epithelial and biphasic histologic subtypes were distinct. Among the differentially expressed functional gene categories was the ubiquitin-proteasome pathway, which was upregulated in biphasic tumors. Cytotoxicity experiments indicated that 211H cells derived from biphasic tumors were synergistically sensitive to sequential combination regimens containing the proteasome inhibitor bortezomib and oxaliplatin. The mechanism of this synergistic response, which was not detected in cells of epithelial tumor origin, was apoptosis. Together, our results identify the ubiquitin-proteasome pathway as a biomarker of poor prognosis biphasic peritoneal mesothelioma tumors and suggest that proteasome inhibitors could increase the effectiveness of cytotoxic chemotherapy in this subset of patients.

Phase II trial of oxaliplatin and gemcitabine in patients with malignant pleural or peritoneal mesothelioma

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Background: A prior phase II trial of oxaliplatin and gemcitabine in malignant pleural mesothelioma reported activity with a 40% partial response rate and stable disease in 24% of 25 previously untreated patients (Schutte W. et al., Clin Lung Cancer 2003;4:294). This trial was designed to further evaluate the efficacy of oxaliplatin and gemcitabine in patients with malignant pleural or peritoneal mesothelioma. Methods: Patients with histologically-confirmed malignant pleural or peritoneal mesothelioma not amenable to curative surgical treatment are eligible for enrollment on this single-institution phase II trial. One prior chemotherapy regimen is allowed, including pemetrexed with a platinum compound or gemcitabine. Presence of at least one radiologically-measurable lesion that has not been previously irradiated is required. Gemcitabine 1000 mg/m2 IV over 90 minutes is administered followed by oxaliplatin 100 mg/m2 IV over 2 hours on day 1 of a 14-day cycle. Treatment is continued for at least 6 cycles unless unacceptable toxicity or disease progression occurs. The primary outcome is to evaluate efficacy as measured by tumor response rate. The sequential two-stage design allows for enrollment of a total of 29 patients if 3 of 18 patients enrolled in the first stage have at least a partial response. Results: Ten eligible patients have been enrolled thus far and 6 are evaluable for response. Sites of disease include pleural (3) and peritoneal (3), and histologic subtypes are epithelioid (5) and sarcomatoid (1). Four patients had received prior chemotherapy. A total of 42 cycles have been given with a median of 8 cycles per patient. There are no partial or complete responses. Four patients have had stable disease for at least 4 months. Two patients with stable disease had received prior pemetrexed/gemcitabine or pemetrexed/cisplatin. Frequently observed toxicities include grade II fatigue, neuropathy and upper gastrointestinal dysmotility. Conclusion: This regimen of gemcitabine and oxaliplatin may provide disease stabilization in a subset of patients with malignant pleural and peritoneal mesothelioma, including those who have received prior chemotherapy. The regimen is well-tolerated. This study remains open to accrual.

No significant financial relationships to disclose.

Peritoneal mesothelioma

Malignant peritoneal mesothelioma is an aggressive neoplasm that rapidly spreads within the confines of the abdominal cavity to involve most accessible peritoneal and omental surfaces. Current treatments are unsatisfactory, and new approaches are needed. We have noted prolonged survival in selected patients after intensive multimodality treatment. Our current experimental regimen includes initial laparotomy with omentectomy, resection of peritoneal implants, and placement of bilateral peritoneal Port-a-Caths (Sims Deltec, Inc., St. Paul, MN); repeated courses of intraperitoneal chemotherapy with doxorubicin, cisplatin, and interferon gamma; second-look laparotomy and intraoperative hyperthermic perfusion with mitomycin and cisplatin; and whole abdominal radiation. Patients with peritoneal mesothelioma who are not candidates for this approach can sometimes be palliated with systemic (intravenous) chemotherapy using doxorubicin or mitomycin, alone or in combination with cisplatin or carboplatin. Newer agents such as gemcitabine and multitargeted antifolate (pemetrexed disodium, LY231514) show promise of greater effectiveness.

Chemotherapy for malignant mesothelioma

The treatment of malignant mesothelioma (MM) has been challenging. Many series from larger single institutions comprise small numbers of selected patients. Positive studies tend to be published, whereas publication of negative studies is delayed, appears in obscure journals, or does not occur at all. Because of the pleural distribution of the tumor, reliable determination of response is problematic. Finally, the natural history of MM is generally short, but can be quite variable. Nevertheless, doxorubicin, cisplatin, and ifosfamide and perhaps other agents as well have modest activity. Larger phase II studies are now being done by cooperative groups accruing patients from community hospitals as well as from tertiary care centers. In the Cancer and Leukemia Group B study, the response rate in patients with measurable disease was 24% for cisplatin and either mitomycin C and doxorubicin, the highest response rates reported for a cooperative group study. Survival was slightly better for the doxorubicin combination. Studies of new drugs and biologics as well as of novel methods of drug delivery are underway.

Chemotherapy for advanced sarcoma: therapeutic decisions and modalities

In patients who have advanced soft tissue sarcoma that is no longer localized, systemic chemotherapy is the most reasonable option for treatment. The decision to treat or to use experimental or conventional agents should be based on the clinical assessment of anticipated net benefit in quality of life as well as the remote possibility of complete remission or even cure. Asymptomatic elderly patients with relatively stable disease might best be treated with watchful waiting; whereas younger excellent-performance-status patients should be offered the opportunity of participating in phase II or phase I studies of newer drugs and intensification regimens. Of the currently available single agents, only doxorubicin (or epirubicin) and ifosfamide show response rates greater than 20%; both show a definite dose-response relationship. Dacarbazine shows particular activity in uterine leiomyosarcomas. Combination chemotherapy regimens such as doxorubicin-ifosfamide show a higher response rate, but may be more toxic. New agents are needed. The current progress in our understanding of the molecular biology of sarcomas, and our expanded comprehension of the mechanism of action of cytotoxic drugs and the biology of drug resistance is cause for optimism.

Homogeneously staining region in anthracycline-resistant HL-60/AR cells not associated with MDR1 amplification

Anthracycline-resistant HL-60/AR cells and their drug-sensitive HL-60/S counterparts were characterized by karyotypic analysis and examined for the overexpression of DNA and mRNA sequences coding for P-glycoprotein (Pgp). The HL-60/S cells were karyotypically stable over a 5-year period of study (1986-1991), except for an additional small Giemsa-positive band noted at 7q22 in cultures harvested in 1987, but not in 1986. This change did not affect drug sensitivity. The drug-resistant HL-60/AR cells examined in 1986, 1987, and 1991 demonstrated a very stable karyotype. The most striking feature was a large homogeneously staining region in the long arm of chromosome 7 (7q11.2), and translocation of the remainder of the long arm to another centromere. Other changes in the HL-60/AR cells included inversion in 9q, partial deletion of the short arm of chromosome 10p, addition of material to the p arm of der(16), loss of chromosome 22, and the appearance of a new marker chromosome. Both HL-60/S and the HL-60/AR cells were found not to amplify DNA or mRNA sequences coding for the Pgp. Thus, although the HL-60/AR cells possess the classical multidrug resistance phenotype and demonstrate a homogeneously staining region near the region of the MDR1 gene, their resistance is due to mechanisms other than those coded for by MDR1.

Subcellular distribution of daunorubicin in P-glycoprotein-positive and -negative drug-resistant cell lines using laser-assisted confocal microscopy

Four well defined multidrug-resistant cell lines and their drug-sensitive counterparts were examined for intracellular distribution of daunorubicin (DNR) by laser-assisted confocal fluorescence microscopy: P-glycoprotein-negative HL-60/AR cells, and P-glycoprotein-positive P388/ADR, KBV-1, and MCF-7/ADR cells. Both drug sensitive cell lines (HL-60/S, P388/S, KB3-1, and MCF-7/S) and drug-resistant cell lines (HL-60/AR, P388/ADR, KBV-1, and MCF-7/ADR) exposed to DNR showed a similar rapid distribution of drug from the plasma membrane to the perinuclear region within the first 2 min. From 2-10 min, the drug sensitive HL-60/S, P388/S, and MCF-7/S cells redistributed drug to the nucleus and to the cytoplasm in a diffuse pattern. In contrast, drug-resistant HL-60/AR, P388/ADR, and MCF-7/ADR redistributed DNR from the perinuclear region into vesicles distinct from nuclear structures, thereby assuming a "punctate" pattern. This latter redistribution could be inhibited by glucose deprivation (indicating energy dependence), or by lowering the temperature of the medium below 18 degrees C. The differences in distribution between sensitive and resistant cells did not appear to be a function of intracellular DNR content, nor the result of drug cytotoxicity. Drug-sensitive KB3-1 and -resistant KBV-1 cells did not fully follow this pattern in that they demonstrated an intracellular DNR distribution intermediate between HL-60/S and HL-60/AR cells with both "punctate" and nuclear/cytoplasmic uptake sometimes in the same cell. These data indicate that the intracellular distribution of DNR is an important determinant of drug resistance regardless of the overexpression of P-glycoprotein. The intracellular movement of drug requires the presence of glucose and a temperature above 18 degrees C, implicating energy-dependent processes and vesicle fusion in the distribution process. This intracellular transport of DNR away from the nucleus in multidrug-resistant cells may protect putative cell targets such as DNA against drug toxicity.

Membrane glycoprotein changes associated with anthracycline resistance in HL-60 cells

The glycoproteins on the surface of HL-60/S wild-type, drug-sensitive human leukemia cells and HL-60/AR anthracycline-resistant cells which do not overexpress the P-glycoprotein, were characterized by labeling with [35S]-methionine, NaB[3H4], phosphorus 32, or sodium iodide I 125. HL-60/S and HL-60/AR cell lysates and membrane fractions tagged with [35S]-methionine or phosphorus 32 showed no significant differences in their protein patterns as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by autoradiography. HL-60/S cells labeled with NaB[3H4] yielded glycoproteins that were smeared predominantly in the molecular-weight range of 210,000 and 160,000 Da, with pI values ranging between pH 4 and pH 4.4. In contrast, NaB[3H4]-labeled HL-60/AR cells showed 7-8 discrete glycoproteins within a molecular-weight range of 170,000 and 140,000 Da, with pI values also ranging between pH 4 and pH 4.4. In addition, [3H]-glucosamine incorporation into HL-60/S and HL-60/AR cells revealed that the latter showed lower uptake of [3H]-glucosamine than did the former. Following treatment with tunicamycin, [3H]-glucosamine uptake in HL-60/S cells decreased, whereas that in HL-60/AR cells remained unchanged. Surface-membrane radioiodination of HL-60/S and HL-60/AR cells showed two distinct protein electrophoretic patterns, with differences being observed in both the high-(220-95 kDa) and low-molecular-weight ranges (21 kDa). Flow cytometric analysis of HL-60/S and HL-60/AR cells using myeloid and lymphoid antigen-specific antibodies demonstrated no antigenic differences between HL-60/S and HL-60/AR cells. HL-60/S cells incubated in the presence of tunicamycin, an inhibitor of N-linked glycosylation, or the protein kinase C agonist phorbol 12-myristate 13-acetate (PMA) developed a glycoprotein pattern similar to that observed in HL-60/AR cells. In addition, tunicamycin treatment of HL-60/S cells decreased daunorubicin (DNR) retention and altered its intracellular distribution as compared with that in HL-60/AR cells. These data indicate that HL-60/AR cells do not possess either de novo or amplified high-molecular-weight surface-membrane proteins; instead, existing proteins are hypoglycosylated. These results also show that HL-60/AR cells exhibit the multidrug-resistant phenotype in association with altered membrane glycoproteins of both high (220-95 kDa) and low molecular weight (21 kDa), but without overexpression of the P-glycoprotein. Furthermore, in HL-60/S cells, the multidrug-resistant phenotype is partially inducible by inhibition of N-linked glycosylation of cell-surface proteins.

Human leukemic myeloblasts and myeloblastoid cells contain the enzyme cytidine 5'-monophosphate-N-acetylneuraminic acid:Gal beta 1-3GalNAc alpha (2-3)-sialyltransferase

We have examined the role of CMP-NeuAc:Gal beta 1-3GalNAc-R alpha(2-3)-sialyltransferase in fresh leukemia cells and leukemia-derived cell lines. Enzyme activity in normal granulocytes using Gal beta 1-3GalNAc alpha-o-nitrophenyl as substrate was 1.5 +/- 0.7 nmol/mg/h whereas activity in morphologically mature granulocytes from 6 patients with chronic myelogenous leukemia (CML) was 4.2 +/- 1.6 nmol/mg/h (P less than 0.05). Myeloblasts from 5 patients with CML in blast crisis showed enzyme activity levels of 6.5 +/- 2.5 nmol/mg/h. From 2 patients with CML, both blasts and granulocytes were obtained, with higher enzyme activity in the patients' blasts (7.1 nmol/mg/h) than in their granulocytes (4.9 nmol/mg/h) in both cases, suggesting that the increase in enzyme activity is related to the differentiation or proliferation status of the CML cells. However, similarly high enzyme levels were also seen in myeloblasts from acute myeloblastic leukemia patients (5.6 +/- 1.4 nmol/mg/h) and in some acute myeloblastic leukemia-derived cell lines (KG1a and HL60), suggesting that increased levels of this enzyme are not directly correlated with the presence of the Ph1 chromosome. This alpha(2-3)-sialyltransferase activity can also be detected in normal peripheral blood lymphocytes and exhibits increased activity in chronic lymphocytic leukemia cells and acute lymphoblastic leukemia. These data suggest that the level of enzyme activity may vary with growth rate and maturation status in myeloid and lymphoid hemopoietic cells. Finally, we have identified a glycoprotein in acute myeloblastic leukemia cells that serves as a substrate for the alpha(2-3)-sialyltransferase. The desialylated form of the glycoprotein was resialylated in vitro by the purified placental form of this alpha(2-3)-sialyltransferase and exhibits a molecular weight of about 150,000.

Architectural organization in the interphase nucleus of the protozoan Trypanosoma brucei: location of telomeres and mini-chromosomes

We studied the spatial organization of chromatin in the interphase G1, S and G2 nucleus of the protozoan Trypanosoma brucei, applying in situ hybridization with conventional fluorescence and confocal scanning optical microscopy. The majority of the trypanosome telomere GGGTTA repeats from different chromosomes were found clustered together, either extending in a network through the nuclear interior or localized at the nuclear periphery. The population of one hundred mini-chromosomes was often asymmetrically located: either clustered in a narrow band in close association with the nuclear envelope or distributed into several clusters that segregated into roughly one half of the nucleus. The nuclear organization may undergo modifications during the cell cycle and development. We conclude that non-random spatial positioning of DNA exists in the nucleus of this protozoan. Finding a high level of structural organization in the interphase nucleus of T.brucei is an important first step towards understanding chromosome structure and functioning and its role in the control of gene expression.

Intracellular distribution and pharmacokinetics of daunorubicin in anthracycline-sensitive and -resistant HL-60 cells

Anthracycline-sensitive (HL-60) and -resistant (HL-60/AR) cells, which do not overexpress the P-glycoprotein, each transport and distribute daunorubicin (DNR) into distinct intracellular locations, as visualized by digitized video fluorescence microscopy. At pH 7.4, the fluorescence of DNR in HL-60 cells appears distributed diffusely in both the nucleus and cytoplasm. In contrast, HL-60/AR cells show much less fluorescence in the nucleus and cytoplasm; most of the fluorescence localizes first to the Golgi apparatus and is then gradually shifted to the lysosomes and/or mitochondria. In pharmacokinetic studies, HL-60/AR cells exposed to different extracellular concentrations of [14C]DNR consistently accumulated less radioactive drug than the parent HL-60 cells. Incubation of HL-60/AR cells with sodium azide and deoxyglucose blocked the efflux of [14C]DNR and also prevented the shift of DNR fluorescence from the Golgi apparatus to the lysosomes/mitochondria. The efflux and the intracellular shift of DNR could also be inhibited by lowering the temperature to 18 degrees C, which stops endosomal membrane fusion. When DNR was allowed to accumulate in HL-60 or HL-60/AR cells at pH 5 there was an increase in the proportion of drug fluorescence in the membranes of both HL-60 and HL-60/AR cells; a decrease in the amount of drug retained by HL-60, but not by HL-60/AR cells; and a decrease in the cytostatic effects of DNR on both HL-60 and HL-60/AR cells. These data suggest that DNR resistance is associated with a failure of DNR to pass through membranes and to bind to cytoplasmic and nuclear structures. Instead, most of the drug is taken up by the Golgi apparatus from which it is then shifted to the lysosomes or to mitochondria, or out of the cell.

Role of glutathione and dependent enzymes in anthracycline-resistant HL60/AR cells

We studied the cellular enzymatic defenses against anthracycline-induced free radical damage in the HL60 human myelogenous leukemia cell line and in its anthracycline-resistant subline, HL60/AR. Intracellular glutathione (GSH) levels and gamma-glutamyl transpeptidase activity were lower in HL60/AR than in HL60 cells. Glutathione-S-transferase (GST) and glutathione peroxidase activities were similar in both cell lines. The intracellular distribution of GSH/GST was visualized by digitized video fluorescence microscopy, utilizing the fluorescent probe monochlorobimane fluorescence microscopy, utilizing the fluorescent probe monochlorobimane (MBCl), which is specifically conjugated to GSH by GST. In HL60 cells stained with the MBCl probe, a bright diffuse cytoplasmic and nuclear fluorescence pattern was observed, whereas in HL60/AR cells, the fluorescence was mostly localized to the Golgi apparatus with a lesser component of diffuse cytoplasmic and nuclear fluorescence. Pretreatment of HL60/AR cells with buthionine sulfoximine (BSO) partially reversed resistance to daunorubicin. This effect of BSO on resistance was associated not only with the abolition of localized MBCl fluorescence to the Golgi apparatus but also with increased intracellular accumulation and retention of daunorubicin. The results of our studies demonstrate that inhibition of GSH synthesis in HL60/AR cells results in significant sensitization to daunorubicin and suggest that changes in the intracellular distribution of GSH/GST and/or increased drug retention may be involved in mediating this effect.

Presence of cytidine 5'-monophospho-N-acetylneuraminic acid:Gal beta 1-3GalNAc-R alpha(2-3)-sialyltransferase in normal human leukocytes and increased activity of this enzyme in granulocytes from chronic myelogenous leukemia patients

We have examined granulocytes from patients with chronic myelogenous leukemia (CML) and from normal subjects to determine whether activity of a specific sialyltransferase might account for the aberrant sialylation of O-linked membrane oligosaccharides in CML cells. Total membrane preparations of morphologically mature CML and normal granulocytes were tested for sialyltransferase activity using the substrates galactosyl-beta 1-3-N-acetyl-D-galactosamine-alpha-O-nitrophenyl and N-acetyl-D-galactosamine-alpha-phenyl. N-Acetyl-D-galactosamine-alpha-phenyl was not an acceptor with either CML or normal cells. With galactosyl-beta 1-3-N-acetyl-D-galactosamine-alpha-O-nitrophenyl, sialyltransferase activity was 2.8 times higher in CML cells compared to normal cells. Product identification by high performance liquid chromatography showed that enzyme from both normal and CML granulocytes linked sialic acid to galactosyl-beta 1-3-N-acetyl-D-galactosamine-R by the alpha(2-3) and not the alpha(2-6) linkage. The enzyme CMP-N-acetylneuraminic acid: galactosyl-beta 1-3-N-acetyl-D-galactosamine-R alpha(2-3)-sialyltransferase has not previously been described in human granulocytes. The marked increase in activity of this enzyme in CML and the resulting increase in sialylation may contribute to the pathophysiological behavior of CML granulocytes.

Effect of verapamil and other agents on the distribution of anthracyclines and on reversal of drug resistance

We studied the intracellular distribution of drugs within anthracycline-sensitive and -resistant cells by computer-assisted digitized video fluorescence microscopy. We found that the antitumor antibiotic, daunorubicin, distributes differently in anthracycline-sensitive and -resistant human leukemia cells (HL-60). Verapamil and other agents known to circumvent resistance in pleiotropic drug-resistant cell lines were able to change the pattern of distribution of daunorubicin in the anthracycline-resistant HL-60 cells back to the distribution found in anthracycline-sensitive HL-60 cells. To investigate the biochemical basis for this effect, we studied the distribution of daunorubicin and doxorubicin in a hydrophobic/hydrophilic (membrane/cytoplasmic) environment using the two-compartment cell-free system of Folch. Our results demonstrate that various unrelated drugs known to overcome resistance will also change the distribution of the anthracyclines in the hydrophobic/hydrophilic compartments. Our data allow the hypothesis that various unrelated agents known to circumvent resistance may act by altering the hydrophobic/hydrophilic solubility of anthracyclines in the resistant cell.

Changes in the granulocyte membrane following chemotherapy for chronic myelogenous leukaemia

Granulocytes from patients with chronic myelogenous leukaemia (CML) have been previously shown to have aberrant sialylation of membrane glycoproteins. We have examined the granulocytes from CML patients receiving intermittent chemotherapy to determine the relationship of the oligosaccharide changes to treatment. Compared to cells from non-leukaemic patients, granulocytes from untreated CML patients showed less adherence to nylon wool, decreased reactivity with peanut lectin, and decreased binding of the synthetic chemotactic peptide formyl-methionine-leucine-phenylalanine (FMLP). Granulocytes from CML patients treated with chemotherapy showed nylon wool adherence, peanut lectin reactivity and FMLP binding comparable to non-leukaemic cells. Chemotherapeutic agents may interfere with oligosaccharide synthesis with a resulting change in the composition of cell surface glycoconjugates.

Increased activity of a specific sialyltransferase in chronic myelogenous leukemia

Granulocytes from patients with chronic myelogenous leukemia (CML) are morphologically identical to their normal counterparts but show marked differences in circulation patterns and in some membrane properties. We have previously shown that there is abnormal lectin binding to CML granulocytes, and aberrant sialylation of membrane glycoproteins. To examine the changes in sialylation of CML granulocytes further, we have studied membrane preparations from CML and normal granulocytes for specific sialyltransferase activity. Because sialyltransferase enzymes are specific for the configuration of the acceptor group, enzyme activity was assayed by measuring transfer of sialic acid from CMP-14C-sialic acid to substrates of defined structure. As compared with those of normal counterparts, CML extracts catalyzed a 50% higher overall rate of sialylation of asialofetuin, a substrate possessing both N- and O-linked acceptors. Studies of enzyme specificity utilizing porcine and ovine submaxillary mucins, antifreeze glycoprotein and alpha-1 acid glycoprotein as acceptors showed that the increased sialylation by CML extracts was due primarily to substrates with the O-linked Gal beta 1----3GaINAc acceptor group. These data suggest that sialyltransferase activity is increased in CML granulocytes compared to normal granulocytes and that the increased enzyme activity is specific for O-linked Gal beta 1----3GaINAc. This enzyme activity may be directly responsible for the abnormal membrane sialylation and pathophysiological behavior of these cells.

Isolation and characterization of an anthracycline-resistant human leukemic cell line

An anthracycline-resistant subline of HL-60 promyelocytic leukemia cells (HL-60/AR) has been isolated in vitro by subculturing in progressively higher concentrations of Adriamycin. The resistant cells are capable of sustaining continuous growth in 10(-6) M Adriamycin which is more than 50 times the 50% inhibitory dose for the parent line. HL-60/AR expressed variable degrees of cross-resistance to daunorubicin, dihydroxyanthracenedione, vincristine, vinblastine, and actinomycin D, but it remained sensitive to methotrexate and 1-beta-D-arabinofuranosylcytosine. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of glycoproteins of HL-60/AR revealed two prominent glycoproteins with molecular weights of 160,000 +/- 10,000 and 110,000 +/- 10,000 which were not detected in the sensitive cells. Cellular uptake and retention of daunorubicin was studied in the resistant and sensitive cells utilizing digitized video fluorescence microscopy. The sensitive cells accumulated more drug and showed at least 2-fold greater levels of brightness than the resistant cells. Studies of total intracellular accumulation, utilizing 10(-6) M [14C]-daunorubicin as a marker, showed a 1-h accumulation of 98 +/- 20 pmol/10(6) cells in HL-60/AR versus 255 +/- 25 pmol/10(6) cells in HL-60. Exposure to nontoxic concentrations of the calcium channel blocker Verapamil (10(-5) M) led to enhanced accumulation (175 +/- 8 pmol/10(6) cells) and retention of the drug in HL-60/AR, resulting in increased cytotoxicity in HL-60/AR. These anthracycline-resistant leukemic cells may serve as a valuable experimental model in studying the phenomenon of multiple drug resistance as well as strategies to circumvent it in human myeloid leukemia.

Effects of pyrimidine antagonists on sialic acid regeneration in HL-60 cells

Because alterations in cell membrane sialoglycoconjugates can affect the behavior of neoplastic cells, we investigated the effects of in vitro treatment with antimetabolites used in cancer therapy on the expression of membrane sialic acid in cultured HL-60 leukemic cells. In these studies, cells were incubated with Vibrio cholerae neuraminidase to remove surface sialic acid. Reappearance of membrane sialic acid during drug treatment was followed (a) by measuring changes in radioactive surface labeling of viable cells with sodium metaperiodate-sodium[3H]-borohydride, (b) by measuring the decline in accessible surface galactosyl receptor sites which occurred coincident with membrane sialic acid replacement, and (c) by measuring the incorporation of [3H]glucosamine into membrane-associated neuraminidase-labile sialic acid. We were especially interested in learning whether drugs that affect intracellular pools of cytidine triphosphate (CTP), an important nucleotide intermediate in sialylation reactions, could inhibit regeneration of membrane sialic acid. 3-Deazauridine, a competitive inhibitor of CTP synthetase, depleted CTP pools and curtailed surface membrane resialylation with little or no effect on synthesis of de novo sialic acid from precursor sugars. The addition of cytidine restored CTP pools and sialic acid regeneration. Acivicin, a glutamine antagonist, also depleted CTP pools and curtailed surface membrane resialylation. In addition, it retarded de novo synthesis of sialic acid. The addition of cytidine restored intracellular CTP pools and sialic acid regeneration. However, both cytidine and guanosine were required to restore sialic acid synthesis from precursor sugars. 1-beta-D-Arabinofuranosylcytosine, a competitive inhibitor of sialic acid synthetase and of sialyltransferase, inhibited both de novo sialic acid synthesis and membrane resialylation. Only the latter effect was reversed by the addition of exogenous cytidine. Hydroxyurea, an agent shown previously to inhibit glycoconjugate production in hamster fibroblasts, curtailed membrane resialylation and de novo synthesis of sialic acid without depleting CTP pools. Doxorubicin, at levels that caused marked arrest of cell proliferation, had no effect on sialic acid synthesis or expression on the membrane surface. These data suggest that antimetabolites, apart from their cytotoxic effects or effects on cellular growth, may directly inhibit the expression of membrane sialic acid.(ABSTRACT TRUNCATED AT 400 WORDS)

Regeneration of membrane sialic acid after neuraminidase treatment of leukemic granulocytes

Granulocytes from patients with chronic myelogenous leukemia (CML) were studied for their ability to regenerate surface sialic acid following treatment with Vibrio cholera neuraminidase (VCN) in vitro. Immediately after neuraminidase treatment, CML and normal granulocytes showed similar incorporation of radioactivity after surface labelling with sodium periodate/potassium-H3-borohydride (PI/BH3(4)). CML granulocytes treated with neuraminidase then incubated for 18 h in nutrient medium showed strikingly increased PI/BH3(4) labelling, usually greater than initial pretreatment values, consistent with a rapid reappearance of sialic acid in the cell membrane. This pattern was not seen in normal granulocytes. The aberrant regeneration of sialic acid in CML granulocytes in vitro could be inhibited by addition of 3 X 10(-6) M retinoic acid, suggesting either a direct effect on membrane glycoconjugate synthesis or an association with granulocyte differentiation.

Assessment of potential exposure to antineoplastic agents in the health care setting

In response to reports of measurable air levels of antineoplastic agents in hospitals and preliminary evidence of exposure to personnel handling these agents, a survey was designed and conducted to document the current handling practices of injectable antineoplastic drugs by hospital and health care workers at two major teaching hospitals and three affiliated community hospitals. The survey included assessment of drug preparation, administration, and disposal. A sample of nurses, pharmacists, physicians, and other staff who routinely come in contact with these drugs was interviewed for validation of the observed results. Typical working conditions encountered and the potential numbers of people at risk and their job titles are presented here. Drug preparation facilities and methods were not uniform even within a single institution, including local preparation in the pharmacy under controlled or uncontrolled conditions, as well as individual drug preparation and administration on the hospital floors. Handling practices for drug preparation were not consistent from practitioner to practitioner. In some cases, where laboratory coats and disposable gloves were provided, it was not a routine practice to wear them. Based on such analysis of risk factors, recommendations for improved practices are given.

Aberrant sialylation of granulocyte membranes in chronic myelogenous leukemia

Peripheral blood granulocytes from patients with chronic myelogenous leukemia (CML) were studied for accessibility of membrane sialic acid and galactose residues to sodium borohydride-3H radiolabeling after oxidation with sodium metaperiodate (PI/B3H4) or with galactose oxidase (GO/B3H4). Granulocytes from untreated patients with chronic myelogenous leukemia showed increased radiolabeling with PI/B3H4, and decreased labeling with GO/B3H4 when compared to normal granulocytes. Granulocytes from leukemic patients receiving chemotherapy showed normal labeling patterns. Gel electrophoresis of membrane extracts showed that the changes in PI/B3H4 and GO/B3H4 reactivity of CML cells were distributed over all membrane protein bands. Our data suggest that CML granulocyte membrane proteins are aberrantly sialylated, with decreased accessibility of galactose residues, and that these changes may be reversed by clinical drug treatment.

Immunotherapy for chronic myelogenous leukemia: survival not affected by treatment in the stable phase

Thirty-one consecutive patients with chronic myelogenous leukemia were treated in the chronic phase with immunotherapy in addition to chemotherapy. Immunotherapy consisted of Bacillus Calmette-Guérin and allogeneic myeloblasts given by vaccination, and chemotherapy comprised busulfan p.o. in most patients. No randomly allocated control group was designated, but patient characteristics appear to be typical of those of other published groups. Twenty-eight of 31 patients were followed from diagnosis to death, and the three remaining patients were followed for over 5 years. The median survival of the patients in our group was 37 months. There was a constant rate of decline in survival with time, with a mean annual death rate of 30% per year. Twenty-five of the 31 patients terminated in blast crisis. One of 21 patients achieved complete remission in blast crisis of myeloid or indeterminate type, and three of four patients achieved complete remission for blast crisis of lymphoid type. The median survival, the rate of decline in survival, and the remission rate in blast crisis do not appear to differ from those of comparable groups of patients treated with chemotherapy alone.

Differences in daunomycin retention in sensitive and resistant P388 leukemic cells as determined by digitized video fluorescence microscopy

Cellular uptake and binding of daunomycin were studied using the digitized video fluorescence microscopy technique, in a sensitive and a resistant subline of P388 leukemic ascites tumor cells. When a 60-min time course of uptake was monitored, the sensitive cells had a 4-fold greater uptake than did the resistant cells. When the cells were perfused with drug-free medium, identical exchangeable levels of the drug were lost from both sublines. The difference in drug uptake could be accounted for entirely on the basis of differences in a slowly exchanging drug fraction which probably represents bound intracellular drug. In glucose-free medium, uptake of daunomycin was accelerated by metabolic inhibition to a greater extent in resistant than in sensitive cells. Furthermore, there was minimal decrease in the fluorescence when both sublines were perfused with drug-free medium. The addition of glucose to this medium induced a significant decrease in fluorescence in resistant but not in sensitive cells. These data raise the possibility that decreased drug uptake in resistant cells associated with decreased slowly exchanging drug fraction may be associated with an inherent defect in drug binding which is reversed by inhibition of energy metabolism. Parallel in vitro and in vivo studies revealed the presence of uptake heterogeneity; both sensitive and resistant cells contained subpopulations (20 to 30%) that have less or more fluorescence than the predominant pattern. This observation demonstrates the possible use of the digitized video fluorescence microscopy for recognizing subsets of cells with different drug susceptibility and to monitor the emergence of anthracycline-resistant cell populations.

Phase II trial of the dopaminergic inhibitor pimozide in previously treated melanoma patients

Pimozide, a potent neuroleptic which inhibits the release of pituitary releasing factors and is an effective dopamine antagonist, was administered to 30 patients with previously treated metastatic melanoma. Six patients were inevaluable because of poor drug tolerance (two), disease progression within 1 week and death within 2 weeks (three), and death from other causes (one). Among the 24 evaluable patients, two had complete response, two had partial response, and two had disease stabilization. Responses were observed in soft tissue, lymph nodes, liver, and lung. Toxic effects consisted of extrapyramidal manifestations in nine patients and malaise in seven. Pimozide has activity in patients with previously treated metastatic melanoma (17% response rate in evaluable patients) and merits consideration of further study in combination regimens.

Digitized video fluorescence microscopy studies of adriamycin interaction with single P388 leukemic cells

We have evaluated a new fluorescent method, the digitized video fluorescence microscopy technique, for the analysis of Adriamycin drug levels in single-cell suspension. This method uses a Leitz microscope equipped with an HBO 50 watt mercury source; the vertical body of the microscope is attached to an intensified silicone intensifier video camera with its output coupled to a video cassette recorder and to an Apple II microcomputer equipped with a video image digitizer. Using this technique, we were able to corroborate previous findings of decreased uptake and increased efflux in resistant as compared to sensitive P388 leukemic cells. This instrument may have wide applications in the study of anthracycline cell interaction or of any other drug with fluorescent properties.

Characterization of compounds shed from the surface of human leukemic myeloblasts in vitro

Human leukemic myeloblasts shed glycoproteins from the cell surface during short-term in vitro culture. Shed surface glycoproteins yield a characteristic profile when studied by gel chromatography, isoelectric focusing, immune precipitation, and polyacrylamide gel electrophoresis. Isolation of immunologically active material yields a compound to approximately 75,000--80,000 daltons, with an isoelectric point of 7.6 to 7.9. Various morphological subtypes of acute myelogenous leukemia shed these compounds, but they are most easily obtained from the more differentiated M2 and M4 types as compared to the undifferentiated M1 type. The shed compounds appear to be quantitatively and qualitatively different from compounds shed by other leukemic cells or nonleukemic cells.

Effects of dopamine agonists and antagonists on murine melanoma: correlation with dopamine binding activity

The biosynthetic pathway melanin is present in many melanomas. Previous investigations have suggested that pharmacologic levels of intermediates in this pathway (L-dopa, dopamine, and their analogues) may inhibit macromolecular synthesis in some tissue culture melanoma cell lines and prolong survival in tumor-bearing mice. Recently, a potent antidopamine drug (pimozide) has been developed. This study was designed to investigate the effects of these drugs on murine melanomas and to correlate effects on macromolecular synthesis with competitive dopamine binding activity (receptors) and melanin synthesis. Three murine melanomas (F1, F10, B16) were studied. The amelanotic B16 cell line showed no inhibition by dopa, dopamine, or pimozide when assayed for 14C-leu or 3H-TdR incorporation. Using a competitive binding assay, only low levels of dopamine binding were present. The very melanotic F1 cell line showed no inhibition by dopa or dopamine, but pimozide inhibited 14C-leu and 3H-TdR incorporation in a dose-response fashion; 50% inhibition was noted at 10(-9) M concentration with no loss in cell viability as tested by trypan blue exclusion or cell counting. Competitive dopamine binding was present (19 pmoles per g of wet tissue) with a Kd of 0.2 nM, figures approximating those seen in normal dog caudate nucleus controls. The F10 line, with melanin production between the B16 and F1, was intermediate in terms of inhibition of 14C-leu and 3H-TdR incorporation and dopamine binding. Purified melanin did not bind and, thus, does not appear to explain these binding results. These data suggest that pimozide, a drug which is a potent dopamine antagonist, may inhibit 14C-leu and 3H-TdR incorporation in murine melanoma cells and that competitive dopamine binding (receptor) appears to correlate with this inhibition. This drug and the dopamine binding assay may be useful in the study of human melanoma.

Immunotherapy for remission maintenance in acute myeloblastic leukemia

Forty-eight patients with acute myeloblastic leukemia in remission were treated with immunotherapy in addition to remission-maintenance chemotherapy. The first 16 patients were treated with weekly BCG and a leukemia cell vaccine (group 1). The next 32 patients were randomly allocated to receive BCG and a leukemia cell vaccine given once monthly (group 2) or BCG given monthly with no leukemia cell vaccine (group 3). There was no significant difference in remission duration or survival between the randomly allocated groups (2 and 3). Comparisons with group 1 are limited by the non-random allocation to this group, but selection bias was unlikely and clinical features were similar in the three patient groups. No significant difference in remission duration or survival was seen amongst the three groups studied. There was no advantage in the addition of leukemia cell vaccine (groups 1 and 2) to BCG alone (group 3) and no advantage to weekly (group 1) versus monthly immunotherapy (groups 2 and 3). Only 7 of the 48 patients achieved a second remission, and 4 of these were short-term partial remissions.

Acute myeloblastic leukemia-associated antigens: detection and clinical importance

Antigenic compounds from the surface of leukemic myeloblasts are shed in vitro on short-term culture. Blast cells radiolabeled by lactoperoxidase iodination release soluble compounds that react immunologically with alloantisera to leukemia-associated antigens. Partially characterized soluble antigens were used to raise heteroantisera in monkeys that are selectively reactive with leukemic myeloblasts and unreactive with nonleukemic cells. Monkey heteroantisera were used to further characterize soluble leukemia antigens. Sera from patients with acute myeloblastic leukemia inhibit the reactivity of the heteroantisera, suggesting that soluble leukemic antigen is released in vivo as well.

Myeloblastic and lymphoblastic markers in acute undifferentiated leukemia and chronic myelogenous leukemia in blast crisis

Blast cells were obtained from 17 patients with acute undifferentiated leukemia and 13 patients with chronic myelogenous leukemia in blast crisis. The blasts were tested with anti-i serum in cytotoxicity tests and with antisera to myeloblastic leukemia-associated antigens in immunofluorescence tests. The terminal deoxynucleotidyl transferase (TDT) content of the blasts was also measured. Lymphoblasts react strongly with anti-i, do not react with anti-myeloblast serum, and have high levels of TDT; myeloblasts react weakly with anti-i, do not react with anti-myeloblast serum, and have very low levels of TDT. Of the 17 patients with acute undifferentiated leukemia, there were six with blasts which reacted like lymphoblasts, six with blasts which reacted like myeloblasts, and five with blasts bearing different combinations of these lymphoblastic and myeloblastic markers. Eight of the 11 patients with lymphoblastic or mixed lymphoblastic-myeloblastic markers, but only one of the six with myeloblastic markers, achieved complete or partial remission in response to therapy. Thus, in acute undifferentiated leukemia, classification of blasts with these markers may be of prognostic value. Of the 13 patients with chronic myelogenous leukemia in blast crises, the markers were concordant (for myeloblasts) in only two cases. Three of the 13 patients had TDT-positive blasts, but the reactions of these cells with anti-i and with anti-myeloblast serum differed from those seen with lymphoblasts from patients with acute lymphoblastic leukemia. Although the cell involved in "lymphoid" blast crisis of chronic myelogenous leukemia is similar in many respects to that involved in acute lymphoblastic leukemia, these cells are not identical.

Serologic characterization of a monkey antiserum to human leukemic myeloblasts

We have raised a monkey antiserum that is selectively reactive with human leukemic myeloblasts by immunization with a glycoprotein antigen (AMLSGA) released from myeloblasts in short-term culture. Antimyeloblast activity can be demonstrated using complement-dependent cytotoxicity or indirect immunofluorescence. Selective antimyeloblast activity is retained following absorption with leukemic lymphoblasts or lymphocytes, nonleukemic lymphocytes, neutrophils, or mononuclear cells from nonleukemic bone marrow. Anti-AMLSGA antisera are not reactive with B-cell-enriched cell populations, and antaimyeloblast activity is not reduced by absorption with Ia-positive cells. Anti-AMLSGA is a useful reagent for identification of human leukemic myeloblasts.