A prospective genome-wide study of prostate cancer metastases reveals association of wnt pathway activation and increased cell cycle proliferation with primary resistance to abiraterone acetate-prednisone.

Background: Genomic aberrations have been identified in metastatic castration-resistant prostate cancer (mCRPC), but molecular predictors of resistance to abiraterone acetate/prednisone (AA/P) treatment are not known. Patients and methods: In a prospective clinical trial, mCRPC patients underwent whole-exome sequencing (n = 82) and RNA sequencing (n = 75) of metastatic biopsies before initiating AA/P with the objective of identifying genomic alterations associated with resistance to AA/P. Primary resistance was determined at 12 weeks of treatment using criteria for progression that included serum prostate-specific antigen measurement, bone and computerized tomography imaging and symptom assessments. Acquired resistance was determined using the end point of time to treatment change (TTTC), defined as time from enrollment until change in treatment from progressive disease. Associations of genomic and transcriptomic alterations with primary resistance were determined using logistic regression, Fisher's exact test, single and multivariate analyses. Cox regression models were utilized for determining association of genomic and transcriptomic alterations with TTTC. Results: At 12 weeks, 32 patients in the cohort had progressed (nonresponders). Median study follow-up was 32.1 months by which time 58 patients had switched treatments due to progression. Median TTTC was 10.1 months (interquartile range: 4.4-24.1). Genes in the Wnt/ß-catenin pathway were more frequently mutated and negative regulators of Wnt/ß-catenin signaling were more frequently deleted or displayed reduced mRNA expression in nonresponders. Additionally, mRNA expression of cell cycle regulatory genes was increased in nonresponders. In multivariate models, increased cell cycle proliferation scores (≥ 50) were associated with shorter TTTC (hazard ratio = 2.11, 95% confidence interval: 1.17-3.80; P = 0.01). Conclusions: Wnt/ß-catenin pathway activation and increased cell cycle progression scores can serve as molecular markers for predicting resistance to AA/P therapy.

Treatment of neuroendocrine cancer metastatic to the liver: the role of ablative techniques.

Carcinoid tumors and islet cell neoplasms are neuroendocrine neoplasms with indolent patterns of growth and association with bizarre hormone syndromes. These tumors behave in a relatively protracted and predictable manner, which allows for multiple therapeutic options. Even in the presence of hepatic metastases, the standard of treatment for neuroendocrine malignancy is surgery, either with curative intent or for tumor cytoreduction, i.e., resection of 90% or more of the tumor volume. Image-guided ablation, as either an adjunct to surgery or a primary treatment modality, can be used to treat neuroendocrine cancer metastatic to the liver. Image-guided ablative techniques, including radiofrequency ablation, alcohol injection, and cryoablation, can be used in selected patients to debulk hepatic tumors and improve patient symptoms. Although long-term follow-up data are not available, the surgical literature indicates that significant ablative debulking may improve patient survival. In this review, we discuss metastatic neuroendocrine disease and its treatment options, especially image-guided ablative techniques.

Bioinformatics approaches for cross-species liver cancer analysis based on microarray gene expression profiling.

BACKGROUND: The completion of the sequencing of human, mouse and rat genomes and knowledge of cross-species gene homologies enables studies of differential gene expression in animal models. These types of studies have the potential to greatly enhance our understanding of diseases such as liver cancer in humans. Genes co-expressed across multiple species are most likely to have conserved functions. We have used various bioinformatics approaches to examine microarray expression profiles from liver neoplasms that arise in albumin-SV40 transgenic rats to elucidate genes, chromosome aberrations and pathways that might be associated with human liver cancer. RESULTS: In this study, we first identified 2223 differentially expressed genes by comparing gene expression profiles for two control, two adenoma and two carcinoma samples using an F-test. These genes were subsequently mapped to the rat chromosomes using a novel visualization tool, the Chromosome Plot. Using the same plot, we further mapped the significant genes to orthologous chromosomal locations in human and mouse. Many genes expressed in rat 1q that are amplified in rat liver cancer map to the human chromosomes 10, 11 and 19 and to the mouse chromosomes 7, 17 and 19, which have been implicated in studies of human and mouse liver cancer. Using Comparative Genomics Microarray Analysis (CGMA), we identified regions of potential aberrations in human. Lastly, a pathway analysis was conducted to predict altered human pathways based on statistical analysis and extrapolation from the rat data. All of the identified pathways have been known to be important in the etiology of human liver cancer, including cell cycle control, cell growth and differentiation, apoptosis, transcriptional regulation, and protein metabolism. CONCLUSION: The study demonstrates that the hepatic gene expression profiles from the albumin-SV40 transgenic rat model revealed genes, pathways and chromosome alterations consistent with experimental and clinical research in human liver cancer. The bioinformatics tools presented in this paper are essential for cross species extrapolation and mapping of microarray data, its analysis and interpretation.

Gemcitabine and oxaliplatin for metastatic pancreatic adenocarcinoma: a North Central Cancer Treatment Group phase II study.

BACKGROUND: This study was performed to determine the efficacy of gemcitabine and oxaliplatin in patients with advanced or metastatic pancreatic adenocarcinoma (ACA). PATIENTS AND METHODS: Pancreatic ACA patients with previously untreated advanced or metastatic disease were enrolled in a phase II study of gemcitabine and oxaliplatin. Oxaliplatin was given i.v. on day 1 and gemcitabine i.v. on days 1 and 8 of a 3-week cycle. The primary end point of the trial was 6-month survival. Secondary end points included response rate, overall survival, median time to progression and toxicity. RESULTS: A total of 47 patients were enrolled, 46 of whom were evaluable. Of those patients assessed for the primary end point 50% lived for > or =6 months. The median time to progression was 4.53 months. Five confirmed responses were seen with a median duration of response of 2.7 months. Overall, the treatment was well tolerated. However, one patient died as a result of treatment-related hemolytic uremic syndrome. CONCLUSIONS: Gemcitabine and oxaliplatin, at doses of 1000 mg/m(2) and 100 mg/m(2), respectively, showed moderate activity in patients with pancreatic ACA. Based on the results of this study further evaluation of this combination is warranted.

A phase I study of sequential irinotecan and 5-fluorouracil/leucovorin.

BACKGROUND: Irinotecan (CPT-11) and 5-fluorouracil (5-FU)/leucovorin are active agents in colorectal cancer. A sequence-dependent synergism of SN-38 followed by 5-FU/leucovorin in vitro led us to conduct a phase I trial of CPT-11 followed by 5-FU/leucovorin to determine the maximum tolerated dose (MTD) and toxicities of this regimen and to obtain preliminary indications of its activity in patients with advanced solid tumors. PATIENTS AND METHODS: Fifty-six patients were enrolled in sequential cohorts to receive escalating doses of CPT-11 (90 min infusion) on day 1, followed by leucovorin 20 mg/m(2) (intravenous push) and 5-FU (90 min infusion) on days 2-5 of each 21-day cycle. RESULTS: A total of 347 treatment cycles (median 4, range 1-25) were administered. Dose-limiting toxicities were diarrhea, neutropenia and fatigue. Nine patients with colorectal cancer and one with gastric cancer had partial or minor responses. Eight of the 10 had prior chemotherapy. CONCLUSIONS: CPT-11 and 5-FU/leucovorin, as constituents of this novel mechanism-based schedule, have promising activity in patients who have received prior chemotherapy. The recommended phase II/III starting doses are CPT-11 275 mg/m(2) over 90 min on day 1, and 5-FU 400 mg/m(2) plus leucovorin 20 mg/m(2) on days 2-5 every 21 days. This combination can be administered safely to this schedule if there is strict adherence to the 90 min infusion time for both CPT-11 and 5-FU.

Gemcitabine and oxaliplatin for patients with advanced or metastatic pancreatic cancer: a North Central Cancer Treatment Group (NCCTG) phase I study.

BACKGROUND: The study was performed to determine the maximum tolerated dose (MTD) of gemcitabine and oxaliplatin in patients with advanced or metastatic pancreatic adenocarcinoma (ACA). PATIENTS AND METHODS: Pancreatic ACA patients, with previously untreated advanced or metastatic disease, were enrolled in a dose escalation study of gemcitabine and oxaliplatin. Oxaliplatin was given intravenously on day 1 and gemcitabine intravenously on days 1 and 8 of a 3-week cycle. Doses of both drugs were increased with sequential cohorts of patients until dose-limiting toxicity (DLT) was observed. RESULTS: A total of 18 patients were enrolled to three dose levels. DLT of neutropenia and a severe infection was noted at a dose of gemcitabine 1250 mg/m2 and oxaliplatin 130 mg/m2. Hematological toxicity and nausea and vomiting were the most common grade 3/4 toxicities. The MTD, gemcitabine 1000 mg/m2 and oxaliplatin 100 mg/m2, was well tolerated. Three confirmed responses were seen. CONCLUSIONS: The MTD of gemcitabine and oxaliplatin in patients with pancreatic ACA was determined. A phase II study of this combination is ongoing and will be reported separately at a later date.

Limited sampling models for CPT-11, SN-38, and SN-38 glucuronide.

PURPOSE: We developed limited sampling models (LSMs) for predicting the area under the curve (AUC) of irinotecan (CPT-11) and its metabolites SN-38 and SN-38 glucuronide (SN-38G). PATIENTS AND METHODS: Regression models were developed based on data from a phase I clinical trial involving 34 patients with advanced solid tumor malignancies who received CPT-11 as a 90-min infusion on an every 3-week dosing schedule. Multiple stepwise regression procedures were supplemented by all possible subsets regression analysis. Alternative clinically based and empirically derived LSMs were determined via model validation assessment including bootstrap simulation testing. RESULTS: The best LSMs for CPT-11 AUC included concentrations recorded at the end of infusion and 4 h later with an option to include a blood draw at 7.5 h from infusion start. For SN-38 and SN-38G AUC, optimal LSMs included the additional metabolite concentration at 48 h after infusion. The LSMs were able to predict most patient AUC values to within 10% of the true value. CONCLUSION: CPT-11 AUC can be modeled with acceptable accuracy using only two or three plasma concentration time-points. A variety of LSM alternatives provided comparable accuracy in predicting AUC. Given the wide variety of LSM alternatives, clinical considerations and patient burden become more important performance parameters than statistical considerations for the choice of time-points in constructing LSMs.

Immunohistochemical localization and semi-quantitation of hepatic tamoxifen-DNA adducts in rats exposed orally to tamoxifen.

Administration of tamoxifen (TAM) has been shown to induce hepatocellular carcinogenesis and TAM-DNA adduct formation in rat liver. Here we present TAM-DNA adduct localization and semi-quantitation in hepatic tissue of rats by immunohistochemical staining followed by image analysis. We have also used a quantitative immunoassay to provide a validation for the immunohistochemical values. Rats were fed diets containing 0, 5, 50, 150 or 500 p.p.m. TAM for 45 weeks. Serial sections of paraffin-embedded liver were stained for TAM-DNA adducts using a polyclonal TAM-DNA antiserum. Subsequently, visualization of TAM-DNA adducts was performed by peroxidase-conjugated secondary antibody-mediated signal amplification using biotinyl tyramide followed by streptavidin-alkaline phosphatase and fast red. Semi-quantitation of nuclear color intensity was achieved with an Automated Cellular Imaging System (ACIS), with a detection limit of 1 TAM-DNA adduct per 10(7) nt for these experiments. In parenchymal cells of liver sections from TAM-exposed animals a dose-dependent increase in nuclear staining was observed by ACIS and the TAM-DNA adduct levels determined by ACIS were validated in liver DNA by quantitative chemiluminescence immunoassay (CIA). Comparison of semi-quantitative values determined by ACIS with quantitative values determined by CIA showed a strong correlation (r = 0.924) between the two methods. At 45 weeks of TAM exposure the liver cytoplasm contained placental glutathione S-transferase (GST-p)-positive foci, as indicated by new fuchsin staining. Staining of serial sections revealed a relative lack of TAM-DNA adducts within these enzyme-altered foci. In addition, some GST-p foci contained islands of cells that did not stain for GST-p but were positive for TAM-DNA adduct formation. This study validates the use of ACIS for TAM-DNA adduct formation and demonstrates that steady-state TAM-DNA adduct levels observed in livers of rats chronically fed TAM for several months increase in relation to dose. In addition, unlike the normal surrounding liver, preneoplastic GST-p-positive foci have virtually no TAM-DNA adducts.

Phase I trial of gemcitabine and CPT-11 given weekly for four weeks every six weeks.

BACKGROUND: Our previous studies have shown that the in vitro cytotoxicity of gemcitabine and SN-38, the active metabolite of irinotecan (CPT-11), is synergistic in human tumor cell lines. PATIENTS AND METHODS: Twenty-four patients with solid tumors, refractory to standard chemotherapy or for whom no effective therapy existed (age range 31-74; 7 female, 17 male; ECOG PS 0 = 12, 1 = 11, 2 = 1), received gemcitabine and CPT-11 weekly for four weeks out of every six weeks. Fifty courses of treatment (median 2, range 1-8) were given through five dose levels of gemcitabine/CPT-11 (600/75, 800/75, 800/100, 1000/100, 1000/125 mg/m2). RESULTS: Grade 3 and 4 neutropenia occurred in eight and two patients, respectively. Grade 3 and 4 thrombocytopenia occurred in one and three patients, respectively. Hematologic toxicity resulted in > or = 2 missed doses of treatment in two out of six patients and was therefore dose limiting at gemcitabine 1000 mg/m2 and CPT-11 125 mg/m2. Grade 3 and 4 diarrhea occurred in two and one patients, respectively. Other moderate non-hematologic toxicities included alopecia, anorexia, fatigue, nausea, vomiting, and weight loss. CONCLUSIONS: The maximum tolerated dose for this study recommended for phase II testing is gemcitabine 1000 mg/m2 and CPT-11 100 mg/m2. A partial response was seen in transitional cell carcinoma.

Phase I study of the matrix metalloproteinase inhibitor, BAY 12-9566.

BACKGROUND: Matrix metalloproteinases (MMPs) are involved in tumor invasion and metastasis and have been implicated in breast, ovarian, colorectal, and lung cancer growth. We undertook a phase I study of BAY 12-9566, an inhibitor of MMP-2, MMP-9, and MMP-3, in patients with solid tumors to determine its safety, pharmacokinetics, and effects on potential surrogate markers of biologic activity. PATIENTS AND METHODS: BAY 12-9566 was orally administered daily at four dose levels; 400 mg daily, 400 mg b.i.d., 400 mg t.i.d., and 800 mg b.i.d. Drug disposition was determined on days 1 and 29 with weekly trough levels measured during the first four weeks. Plasma vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and urinary pyridinoline and deoxypyridinoline crosslinks were determined at baseline, once weekly for four weeks, and then every four weeks. RESULTS: Thirteen patients were entered on trial. BAY 12-9566 was well tolerated, with only one grade 3 headache, one grade 3 anemia, one grade 3 thrombocytopenia, and no musculoskeletal effects. The median treatment duration was 57 days (range 7-560). Mean trough levels of BAY 12-9566 on day 28 ranged from 80.5 to 108.6 mg/l. Plasma trough levels were 1500-42,000-fold above the Ki's for MMP-2, MMP-3, and MMP-9 at the 800 mg p.o. b.i.d. dose level. There was no significant change in VEGF, bFGF, pyridinoline, and deoxypyridinoline crosslinks with BAY 12-9566 administration. CONCLUSIONS: The recommended dose for further testing is 800 mg p.o. b.i.d.

A Phase II study of high-dose paclitaxel in patients with advanced neuroendocrine tumors.

BACKGROUND: New agents with antitumor activity in patients with neuroendocrine tumors are sorely needed. A Phase II study of high-dose paclitaxel in patients with metastatic carcinoid and islet cell tumors was performed at the Mayo Clinic. Granulocyte-colony-stimulating factor (GCSF) also was administered to ameliorate neutropenia. METHODS: Twenty-four patients (14 with carcinoid tumors, 9 with islet cell tumors, and 1 with an anaplastic tumor) were enrolled on this Phase II study of paclitaxel given as a 24-hour continuous infusion at a dose of 250 mg/m(2) every 3 weeks plus GCSF at a dose of 5 microg/kg/day subcutaneously, beginning 24 hours after the completion of the paclitaxel dose and continuing until the absolute neutrophil count was > 10,000/microL. RESULTS: All 24 patients were evaluable for analysis. The overall response rate was 8% (95% confidence interval [95% CI], 0-0.11). At last follow-up all patients except 1 had developed disease progression, with an estimated median time to disease progression of 3.2 months (95% CI, 1.6-6.0 months). The estimated median survival was 1.5 years (95% CI, 1.0-1.8 years). Hematologic toxicity was significant with 12 of 24 patients developing Grade 4 (according to the National Cancer Institute Common Toxicity Criteria scale) neutropenia; however, there were no septic deaths reported. There were 17 episodes of Grade 4 neutropenia in these 12 patients and the duration of these events ranged from 2-5 days. More common nonhematologic toxicities included arthralgia (21 patients), anorexia (15 patients), nausea (15 patients), diarrhea (12 patients), and allergic reactions (2 patients). CONCLUSIONS: Given the lack of antitumor activity of paclitaxel and the significant hematologic toxicity observed despite the use of GCSF support in the current study cohort of patients with neuroendocrine tumors, further studies of this combination in this particular patient population are not recommended.

Future directions in adjuvant therapy for stage III colon carcinoma.

The current recommendation for adjuvant chemotherapy for patients with newly diagnosed stage III colon cancer involves 6 months of fluorouracil (5-FU) plus low- or high-dose leucovorin. In clinical trials performed throughout the world, several drugs have demonstrated either improved toxicity profiles or antitumor activity for patients with advanced colorectal carcinoma. Uracil and tegafur (UFT) and capecitabine (Xeloda) are two examples of new oral chemotherapy compounds with acceptable side-effect profiles in early adjuvant or advanced disease trials. Irinotecan (CPT-11, Camptosar) and oxaliplatin, when administered intravenously in combination with a 5-FU regimen, have both demonstrated significant antitumor effects for patients with advanced-stage disease. Other immunotherapies, including monoclonal antibodies and cancer vaccines, are being evaluated to help stimulate immune responses in patients with resected colon cancer. These agents are just a few examples of the new compounds being tested in the next generation of clinical trials for resected stage III colon cancer. Future and ongoing investigations will look to integrate these new therapies as we attempt to move beyond the era of 5-FU and leucovorin.

A clonal growth model: time-course simulations of liver foci growth following penta- or hexachlorobenzene treatment in a medium-term bioassay.

A combination of experimental and simulation approaches were used to analyze the clonal growth of preneoplastic, enzyme-altered foci during liver carcinogenesis in an initiation-promotion regimen. Male Fisher 344 rats, 8 weeks of age, were initiated with a single dose (200 mg/kg, i.p.) of diethylnitrosamine (DEN). Beginning 2 weeks later, animals were exposed to daily gavage consisting of 0.1 mmol/kg pentachlorobenzene (PECB) or hexachlorobenzene (HCB) in corn oil vehicle for 6 weeks. Partial hepatectomy was performed 3 weeks after initiation. Experimental data including liver weight, hepatocyte density (number of hepatocytes/unit volume), 5-bromo-2'-deoxyuridine-labeling index for analysis of cell division rate, and number and volume of glutathione-S-transferase pi-positive foci were collected 23, 26, 28, 47, or 56 days after initiation. Model parameters describing liver growth were obtained directly from the experimental data. The probability of mutation/division of normal cells and the growth rate of initiated cells were inferred by a comparison of model outcomes with the observed time courses of foci development. To describe the time-dependent increases in foci volume and the concomitant reduction of foci number observed in all treatment groups, the calibrated model for the DEN controls incorporated the hypothesis of two initiated cell populations (referred to as A and B cells) within the framework of the two-stage model. The B cells are initiated cells that have a selective growth advantage under conditions that inhibit the growth of A cells and normal hepatocytes. The parameter values defined in the DEN controls were used to evaluate experiments involving the administration of PECB or HCB. Both PECB and HCB caused a significant increase in foci volume compared with the DEN controls. HCB treatments resulted in increased proliferation of normal hepatocytes, which was not observed for PECB under the same treatment regimen. The best description of the data resulted from the model incorporating the hypothesis that PECB and HCB promoted the growth of foci via increased net growth rates of B cells. We present here a biologically based clonal growth simulation platform to describe the growth of preneoplastic foci under experimental manipulations of initiation-promotion studies. This simulation work is an example of quantitative approaches that could be useful for the analysis of other initiation-promotion studies.

Animal models of neoplastic development.

The basic animal model for neoplastic development used by regulatory agencies is the two-year chronic bioassay developed more than 30 years ago and based on the presumed mechanism of action of a few potential chemical carcinogens. Since that time, a variety of other model carcinogenic systems have been developed, usually involving shorter duration, single organ endpoints, multistage models, and those in genetically-engineered mice. The chronic bioassay is still the "gold standard" of regulatory agencies despite a number of deficiencies, while in this country the use of shorter term assays based on single organ endpoints has not been popular. The multistage model of carcinogenesis in mouse epidermis actually preceded the development of the chronic two-year bioassay, but it was not until multistage models in other organ systems were developed that the usefulness of such systems became apparent. Recently, several genetically-engineered mouse lines involving mutations in proto-oncogenes and tumour suppressor genes have been proposed as additional model systems for use in regulatory decisions. It is likely that a combination of several of these model systems may be most useful in both practical and basic applications of cancer prevention and therapy.

Phase II study of paclitaxel and cisplatin for advanced urothelial cancer.

PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer.

A North Central Cancer Treatment Group Phase II trial of 9-aminocamptothecin in previously untreated patients with measurable metastatic colorectal carcinoma.

BACKGROUND: Topoisomerase I inhibitors have demonstrated clinical activity in patients with metastatic colorectal carcinoma. The authors performed a Phase II study to evaluate the objective tumor response rate of 2 different doses and schedules of 9-aminocamptothecin (9-AC) in previously untreated patients with measurable recurrent metastatic colorectal carcinoma. METHODS: Fifty-one patients were registered. One schedule evaluated 9-AC given at 1100 microgram/m(2)/24 hours by continuous infusion for 72 hours along with granulocyte-colony stimulating factor at 5 microgram/kg/day on Days 5 through 12. Another schedule involved 9-AC at 480 microgram/m(2)/24 hours by continuous infusion for 120 hours on Days 1, 8, and 15 given every 4 weeks. RESULTS: Forty-eight of 51 patients (94%) were evaluable (28 patients who received 72-hour infusion and 20 patients who received 120-hour infusion) for response and toxicity. Significant hematologic toxicities were encountered, especially with the 72-hour infusion schedule, in which 43% (12 of 28) and 28% (8 of 28) experienced Grade 4 (National Cancer Institute Common Toxicity Criteria) leukopenia and thrombocytopenia, respectively. Grade 4 neutropenia was encountered in 61% (17 of 28) and 11% (2 of 19) of patients on the 72-hour and 120-hour infusion schedules, respectively. Diarrhea, nausea, vomiting, and hepatotoxicity were troublesome nonhematologic toxicities. Seventy-nine percent (11 of 14) and 57% (4 of 7) of the patients experiencing Grade 3 or 4 nonhematologic toxicity were on the 72-hour infusion schedule. Three patients died of chemotherapy-related toxicity. One response was observed in 48 evaluable patients (2%). CONCLUSIONS: 9-AC did not demonstrate sufficient antitumor activity and had unacceptable toxicity in previously untreated patients with metastatic colorectal carcinoma.

Nuclear-labeling index analysis (NLIA), a software package used to perform accurate automation of cell nuclear-labeling index analysis on immunohistochemically stained rat liver samples.

The nuclear labeling index (labeled nuclei/100 nuclei) and the apoptotic index (apoptotic cells/100 cells) are important parameters of cell growth and death. Automatic counting of labeled nuclei is desirable since manual counting is tedious, time-consuming, and with a greater potential for inaccuracies. A nuclear-labeling index analysis (NLIA) software package was developed in this laboratory to perform the counting process automatically and accurately. This software package consists of an application program NLIA and a set of macros for obtaining nuclear data that is used in Scion Image. It is designed to work cooperatively with Scion Image, Adobe Photoshop, and Microsoft Office. NLIA has two basic functions: building nuclear data files and analyzing nuclear data. A color image captured from an immunohistochemically stained or autoradiographic sample is loaded into NLIA. Nuclear data can be entered into the program manually, automatically, or in combination. In the manual data entering mode, NLIA acts as an object-counting tool, while in the automatic mode it acts as a data picker: picking up the data generated by Scion Image into memory. A method to enter nuclear data (both labeled nuclei and unlabeled nuclei) in the automatic mode is described. The color image is processed in Adobe Photoshop, where the interested color ranges are selected and separated. These are then analyzed in Scion Image with the help of the macros for obtaining nuclear data. Since the advanced particle analysis function is used, the counting process is automatic and rapid. Data from thousands of nuclei can be obtained within seconds. To ensure the accuracy of the analysis, a nuclear data checking and edit feature is employed in NLIA: results of computer-generated counting can be compared with the original color image by overlaying the plot of counting results onto the original color image. In this way any computer counting mistakes can be easily discovered and corrected by the operator. Corrected nuclear data (including nuclear size, location, shape) are then stored in data files. These data files can be used in NLIA to obtain cell density and nuclear labeling indices. Because criteria for obtaining nuclear data (truncation diameter, shape factor) can be set by the operator in NLIA, nuclear size distribution and shape variation can be analyzed. This method provides a fast and accurate way to determine cell nuclear-labeling indices. Currently, Scion Image is a freeware on the internet, and NLIA software package is available from our lab home page. Methods presented here expand the Scion Image ability to analyze color images by using color separation techniques in a commercial graphic application. The instrumentation required can be relatively inexpensive, and the methods described may be useful in studies of cell kinetics, lesion growth, and tumor therapy.

Priming tissue-specific cellular immunity in a phase I trial of autologous dendritic cells for prostate cancer.

We attempted to induce therapeutic immunity against prostate-derived tissues in patients suffering from progressive hormone-refractory metastatic prostate carcinoma. Thirteen patients were treated with two infusions, 1 month apart, of autologous dendritic cells (APC8015) preexposed ex vivo to PA2024, a fusion protein consisting of human granulocyte/macrophage-colony stimulating factor (GM-CSF) and human prostatic acid phosphatase (PAP). The infusions were followed by three s.c. monthly doses of PA2024 without cells. Three groups of patients each received PA2024 at 0.3, 0.6, or 1.0 mg/injection. All Ps were two-sided. Treatment was well tolerated. After infusions of APC8015, patients experienced only mild (grade 1-2) short-lived fever and/or chills, myalgia, pain, and fatigue. One patient developed grade 3 fatigue. Four patients developed mild local reactions to s.c. PA2024. Twelve patients were evaluable for response to treatment. Circulating prostate-specific antigen levels dropped in three patients. T cells, drawn from patients after infusions of APC8015, but not before, could be stimulated in vitro by GM-CSF (P = 0.0004) and PAP (P = 0.0001), demonstrating broken immune tolerance against these two normal proteins. Injections of PA2024 did not influence the reactivity of T cells against PAP and GM-CSF. However, antibodies to GM-CSF and, to a much lesser extent, to PAP reached maximum titers only after two or even three injections of PA2024, showing that directly injected PA2024 was involved in stimulation of humoral immunity. Dendritic cells exposed to antigen ex vivo can induce antigen-specific cellular immunity in prostate cancer patients, warranting further studies of this mode of immunotherapy.

Phase I dose-finding and pharmacokinetic trial of irinotecan hydrochloride (CPT-11) using a once-every-three-week dosing schedule for patients with advanced solid tumor malignancy.

A Phase I study was performed to determine the maximum tolerated dose (MTD), toxicities, and pharmacokinetic profile of irinotecan (CPT-11) and its active metabolites when given on a once-every-3-week schedule. Thirty-four patients with advanced refractory solid malignancies were treated with CPT-11 (240-340 mg/m2) administered as a 90-min i.v. infusion every 3 weeks. Patients were divided into two groups: those with and those without prior abdominal/pelvic (AP) radiotherapy. Gastrointestinal toxicity (nausea, vomiting, and diarrhea) and hematological toxicity (leukopenia and neutropenia) were dose-limiting side effects. Other common toxicities included anorexia, asthenia, and acute cholinergic symptoms (abdominal cramps, diaphoresis, and lacrimation). For patients with no prior AP radiation therapy, the MTD was determined to be 320 mg/m2, whereas those with prior AP radiation therapy had a MTD of 290 mg/m2. Dose-proportional increases in the mean area under the concentration-time curves for CPT-11, SN-38, and SN-38G were not observed over the narrow dose range studied. Mean values of terminal phase half-life, clearance, terminal phase volume of distribution, and steady-state volume of distribution for CPT-11 were 12.4 +/- 1.8 h, 13.0 +/- 3.8 liters/h/m2, 234 +/- 83 liters/m2, and 123 +/- 38 liters/m2, respectively. The pharmacodynamic analyses indicated the strongest correlation to be between SN-38 area under the concentration-time curves and neutropenia (p = 0.60; P = 0.001). A total of five responses (one complete response and four partial responses) were observed in the cohort of 32 patients with previously treated metastatic colorectal carcinoma. In conclusion, gastrointestinal toxicity and hematological toxicity were the dose-limiting toxicities of CPT-11 when administered as a 90-min infusion every 3 weeks. In this trial, the recommended Phase II starting dose for patients with no prior AP radiation therapy was found to be 320 mg/m2; for patients with prior AP radiation, the recommended Phase II starting dose was 290 mg/m2. This once-every-3-week schedule has been incorporated into a Phase I trial of CPT-11 combined with 5-fluorouracil and leucovorin.