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Journal of Immunotherapy | 1993

Establishing in vitro cultures of autologous tumor cells for use in active specific immunotherapy.

Robert O. Dillman; Shankar K. Nayak; Linda D. Beutel

Summary For active specific immunotherapy, autologous tumor cells grown in vitro may be a more appropriate source of tumor antigen than allogeneic tumor cell lines, autologous tumor cell suspensions, or purified/synthetic tumor antigen. A major limitation to this approach, however, has been the ability to reliably grow tumor cells from a high percentage of fresh tumor samples. We have harvested fresh tumors and attempted to establish short-term cultures of tumor cells to obtain 108 cells which could subsequently be used in autologous tumor cell vaccine programs. Fresh tumors were mechanically processed to initiate primary cultures in RPMI-1640 containing 1 m Mglutamine, 10 mM N-(2-hydroxyethyl)piperazine-N‘-(2-ethanesulfonic acid), 15% fetal bovine serum, and antibiotics, incubated at 37°C in 5% CO2. We were successful in growing 87 of 142 [61%, (95% confidence limits [55–68%]) of all tumors] including 39 of 58 (67%) melanomas, 10 of 10 (100%) renal cell carcinomas, 14 of 14 (100%) sarcomas, and 23 of 54 (43%) various adenocarcinomas. Success rates were not significantly higher in tumors obtained locally that were processed within 4 h of surgery, 51 of 78 (65%) versus 36 of 64 (56%) of those from farther away with longer delays in processing (p = 0.276). Of the 87 tumor cell lines established, 51 have been expanded for use in autologous tumor cell vaccine programs, and 40 have been used in the treatment of patients. We conclude that autologous tumors can be grown in vitro with sufficient reliability to make an autologous tumor cell line vaccine trial feasible.


Cancer Biotherapy and Radiopharmaceuticals | 2002

Irradiated Cells from Autologous Tumor Cell Lines as Patient-Specific Vaccine Therapy in 125 Patients with Metastatic Cancer: Induction of Delayed-Type Hypersensitivity to Autologous Tumor is Associated with Improved Survival

Robert O. Dillman; Linda D. Beutel; Neil M. Barth; Cristina de Leon; Audrey A. O'Connor; B. S. N. Carol Depriest; Shankar K. Nayak

OBJECTIVE We established short-term cultures of pure tumor cells for use as autologous tumor cell vaccines in an effort to study the effects of patients-specific immunotherapy. PATIENTS AND METHODS Surgically resected fresh tumor was obtained from patients with metastatic cancer. Successful tumor cell lines (5 x 10(7)) were expanded to 10(8) cells, irradiated, and cryopreserved for clinical use. Following a baseline test of delayed-type hypersensitivity (DTH) to an i.d. injection of 10(6) irradiated autologous tumor cells, patients received 3 weekly s.c. injections of 10(7) cells, had a repeat DTH test at week-4, then received monthly vaccinations for 5 months. A positive DTH test was defined as > or = 10 mm induration; survival was determined from the first DTH test. RESULTS Short-term cell lines were successfully established for 299/695 patients (43%). Vaccines were prepared for 231 patients, 142 of whom were treated, and 125 had a baseline DTH test recorded. Median follow up at the time of analysis was greater than 5 years. There was no difference in survival for any of the following: gender, age > 50 years, melanoma histology, anergy to common recall antigens or baseline DTH test result. Only 17 patients had a positive DTH at baseline (14%), but DTH converted from negative to positive in 31/80 (39%) of those who were tested, and in 31/108 (29%) of all patients (intent-to-convert analysis). For the 48 patients who were DTH-positive at entry, or converted to DTH-positive, the median survival was 30.5 months and 5-year survival 41% compared to 11.4 months and 9% 5-year survival for 77 patients whose DTH was never positive (P2 = 0.003). However, survival was even better for patients whose DTH test converted to positive compared to patients who were DTH-positive at baseline (median 37.5 vs 11.9 mos, P2 = 0.066). CONCLUSION This patient-specific, cell culture-derived, autologous tumor cell vaccine induced anti-tumor immune reactivity that was associated with improved survival in patients with advanced cancer.


Journal of Immunotherapy | 2003

Interferon-gamma or Granulocyte-macrophage Colony-stimulating Factor Administered as Adjuvants With a Vaccine of Irradiated Autologous Tumor Cells From Short-term Cell Line Cultures: A Randomized Phase 2 Trial of the Cancer Biotherapy Research Group

Robert O. Dillman; Wiemann M; Shankar K. Nayak; DeLeon C; Hood K; Carol DePriest

The objective was to study the effects of patient-specific vaccine immunotherapy administered with either interferon-gamma (IFN&ggr;) or granulocyte-macrophage colony stimulating factor (GM-CSF) in patients with metastatic cancer. Short-term cell lines were established from cancer tissue resected from patients with metastatic cancer for use as autologous tumor cell vaccines. Successful cultures were expanded to 1 to 2 × 108 cells, irradiated, and cryopreserved in aliquots of 106 cells for intradermal testing of delayed tumor hypersensitivity and 107 cells for subcutaneous vaccinations. The study design was that of a randomized phase 2 trial. Patients were stratified by tumor type and by whether they had measurable disease at the time vaccination was to commence, and then randomized to receive either 100 MIU IFN&ggr; subcutaneously or 500 &mgr;g GM-CSF subcutaneously at the time of each tumor cell vaccination. Following a baseline test of delayed-type hypersensitivity (DTH) to an intradermal injection of 106 irradiated autologous tumor cells, patients received 3 weekly subcutaneous injections of 107 cells, had a repeat DTH test at week 4, then received monthly vaccinations for 5 months. A positive DTH test was defined as at least 10 mm of induration; survival was determined from the first DTH test. There were 98 patients enrolled with a median follow-up of over 4 years. The most prevalent diagnoses were melanoma (51), renal cell carcinoma (18), and soft-tissue sarcoma (14). There were 49 patients (26 men, 23 women, average age 50.4 years) randomized to IFN&ggr; and 49 (28 men, 21 women, average age 54.1 years) to GM-CSF. The average numbers of vaccine and adjuvant injections were 6.3 and 5.9, respectively. For the patients who received IFN&ggr;, the objective response rate was 0 of 21; for patients who received GM-CSF the response rate was 1 of 26. Only eight patients (four from each arm) had a positive baseline DTH reaction to autologous tumor. The tumor DTH test converted from negative to positive in 13 of 45 of the IFN&ggr; group and 11 of 43 of the GM-CSF group. With 29 patients deceased in the IFN&ggr; arm and 31 in the GM-CSF arm, the 2-year and 5-year survival rates were 45% and 29% for the IFN&ggr; arm and 41% and 23% for the GM-CSF arm (NSD). Both adjuvants were well tolerated and results were similar in both arms of the study. Both adjuvants were associated with a 25% to 30% rate of DTH conversion and a 25% 5-year survival rate. Immune recognition of autologous tumor can be induced with this approach.


Journal of Immunotherapy | 1997

Characterization of Tumor-Infiltrating Lymphocytes Derived from Human Tumors for Use as Adoptive Immunotherapy of Cancer

Patric M. Schiltz; Linda D. Beutel; Shankar K. Nayak; Robert O. Dillman

Summary From 1991 to 1995, we initiated cultures of 94 fresh tumor samples of various histologies in an effort to grow tumor-infiltrating lymphocytes (TIL) using flasks and subsequent expansion in semipermeable bags. The five most prevalent tumor types from which TIL were successfully initiated were melanoma (25 successful initiates in 34 tumor samples, 74% success rate), colorectal cancer (12 of 18, 67%), renal cell carcinoma (9 of 12, 75%), breast (4 of 5, 80%), and sarcoma (5 of 7, 71%). The overall success rate for all tumors was 67 of 94 (71%). There were no instances of contamination from the time of culture initiation through harvesting of the final cell product for clinical use. The mean number of days to reach successful initiation (> 5 X 108 cells) was 35 ± 24 days (mean ± SD). TIL were then expanded from these successful initiates for either a repeated low-dose therapy (TIL reinfusion numbers of 5 X 108–5 X 109) or for a repeated high-dose therapy (> 5 X 109–5 X 1010). The mean number of days to expand a TIL culture from the time of initiation to treatment for a first low-dose TIL was 59 days (range, 27–94 days) compared with 80 days (range, 33–209 days) for high-dose TIL. For patients who received a second or third high-dose TIL treatment, the average number of days needed to expand TIL was 39 days (n = 10) if there was no intervening cryopreservation of TIL, compared with 49 days (n = 10) if the culture had to be reestablished from cryopreserved TIL. For patients who received a second or third low-dose TIL, the mean number of days needed to expand TIL was 23 days (n = 3) if there was no intervening cryopreservation compared with 42 days (n = 17) if cultures had to be reestablished after cryopreservation of TIL. Low-dose TIL displayed predominantly CD4+ phenotype in 76% of 42 cultures, whereas high-dose TIL displayed predominantly CD8+ phenotype in 84% of 44 cultures. Cells bearing the natural killer (NK) phenotype (CD3-, CD56+) and the lymphokine activated killer (LAK) phenotype (CD3+, CD56-) were present in both low- and high-dose TIL cultures, but these phenotypes were never predominant. Cytotoxicity testing consistently demonstrated the persistence of NK and LAK activity in addition to the killing of allogeneic and autologous melanoma tumor targets. This work confirms that TIL cultures from most tumor types can be successfully established and expanded for therapeutic use, and repeated expansion from continuous TIL culture or cryopreserved TIL for repeated treatments is feasible. Such cultures are predominantly T lymphocytes that are phenotypically heterogeneous, and these phenotypes do not remain constant during prolonged time in culture.


Cancer Biotherapy and Radiopharmaceuticals | 2001

Treatment of Kidney Cancer with Autologous Tumor Cell Vaccines of Short-Term Cell Lines Derived from Renal Cell Carcinoma

Robert O. Dillman; Neil M. Barth; Louis A. VanderMolen; David H. Garfield; Cristina de Leon; Audrey A. O'Connor; Khosrow Mahdavi; Shankar K. Nayak

BACKGROUND We established short-term cultures of autologous tumors from patients with renal carcinoma for use as active specific immunotherapy (i.e., autologous vaccine). METHODS Between 9/91 and 9/99 the cell biology laboratory of the Hoag Cancer Center received 69 kidney tumor samples that had been surgically excised, including 43 primary tumors and 26 metastatic lesions. Efforts were made to establish short-term tumor cell cultures to use as autologous tumor cell vaccines. Prior to treatment, patients underwent a baseline skin test for delayed tumor hypersensitivity (DTH) and then received s.c. injections of 10 million irradiated tumor cells that were given with various adjuvants weekly x3 and then monthly x5. RESULTS Cell lines were established for 55/69 patients (80%) including 36/43 (84%) from primary tumors and 19/26 (73%) from distant metastases. Vaccines were prepared for 41 patients; 27 were treated. At the time of this analysis, follow up data was available for 26 patients with a median follow up > 5 years. Treatment was well-tolerated. Of 10 patients who had no evident disease at the time of treatment, nine were alive 1-8 years later; 5/8 had conversion of their DTH test from negative to positive. For 16 patients with measurable metastatic disease at the time of treatment, there were no objective tumor responses; their median survival was 5.0 months. Among these 16 patients, only 1/8 DTH tests converted, but three had a positive baseline DTH test; one was previously treated with interleukin-2 and tumor infiltrating lymphocytes and two others were previously treated with autolymphocyte therapy. CONCLUSIONS Vaccine therapy with short-term cultures of autologous tumor cells is feasible, well-tolerated and associated with conversion of DTH and long-term survival in patients who are free of disease at the time treatment is initiated. However, significant anti-tumor responses were not seen in patients with measurable disease at the time vaccine treatment was initiated.


Breast Cancer Research and Treatment | 1996

High-dose chemotherapy with autologous stem cell rescue in breast cancer

Robert O. Dillman; Neil M. Barth; Shankar K. Nayak; Cristina DeLeon; Audrey A. O'Connor; Laura Morrelli

SummaryBackgroundBecause metastatic breast cancer is a lethal disease despite some responsiveness to systemic chemotherapy, high-dose chemotherapy with autologous stem cell rescue is being utilized with increasing frequency. This analysis was undertaken to determine the outcome for such patients treated with intensive chemotherapy between 1989–1994, at the Hoag Cancer Center in Newport Beach, CA.MethodsDuring 1989, only patients with metastatic disease who had failed more than two standard breast cancer chemotherapy regimens were considered eligible for such treatment. They received high-dose BCNU/ cyclophosphamide/cisplatinum chemotherapy with autologous bone marrow rescue. After January 1990, patients with metastatic disease were eligible only if they had received limited prior chemotherapy and demonstrated responsiveness to induction chemotherapy. Beginning June 1990, patients with metastatic disease were to receive mitoxantrone and thiotepa (MiTepa) followed by peripheral blood stem cell rescue, then ifosfamide, carboplatin and etoposide (ICE) chemotherapy followed by peripheral blood stem cell rescue. High-risk adjuvant patients were to receive one course of ICE followed by rescue.ResultsBetween 1/89–12/94, 48 breast cancer patients underwent 65 intensive chemotherapy treatments followed by autologous stem cell rescue. During 1989, three of the eight patients with metastatic disease died within 60 days because of therapy-related complications. The longest failure-free survival (FFS) of these eight was 12.2 months, and the longest overall survival (OS) 20.5 months. Since 1/90, one physician has treated 24 patients with metastatic breast cancer, 17 of whom actually underwent two successive transplants with MiTepa/ICE. For the latter group, median FFS is 23.2 months; median OS is 39.7 months. There were no acute deaths, but two patients died > 60 days after initial transplant from therapy-related complications, venoocclusive disease (5.2 months) and myelodysplastic syndrome (30.5 months), while five died of progressive disease at 22.5, 32.8, 39.4, 46.3, and 51.3 months. For the 24 metastatic patients treated 1990–1994, 1-, 2-, and 3-year FFS rates are 86%, 40%, and 17%, respectively, while OS rates are 91%, 80%, and 65%. Of 11 patients treated in the adjuvant setting, only one has relapsed (9.8 months) with follow-up from 3–61 months.ConclusionsModifications made in the program, including selection of patients responsive to induction chemotherapy, transfusion of peripheral blood stem cells, implementation of hematopoietic colony stimulating factors, and use of tandem intensive treatments has been associated with a low rate of acute morbidity and encouraging survival rates.


Journal of Interferon and Cytokine Research | 1999

Modulation of Renal Carcinoma Cells In Vitro: Comparison After Transduction with Retroviral Vector Containing a Human IFN-gamma Gene Versus Incubation with Soluble IFN-gamma

Shankar K. Nayak; Patric M. Schiltz; Robert O. Dillman

Transduction of renal cell carcinoma (RCC) cells in vitro with a gene for human interferon-gamma (IFN-gamma) results in enhanced expression of key molecules needed for immune recognition. In this study, we investigated the ability of soluble IFN-gamma protein to enhance expression of these key molecules. RCC cells were incubated with and without IFN-gamma, then analyzed by flow cytometry for the percent positive and mean intensity fluorescence (MIF), a measurement of mean antigen density, of HLA-I, HLA-II, ICAM-1, and tumor antigens (URO-2, URO-3, and URO-4). Results were compared to those seen for RCC cells transduced by IFN-gamma. The ability of cytotoxic T lymphocytes (CTL) to lyse RCC targets was measured using a standard [51Cr]lytic assay. Control cells were 99% (MIF 751) and 98% (MIF 315) positive for HLA-I and ICAM-1, respectively, with 2% (MIF 8) positive for HLA-II. Incubation with IFN-gamma protein resulted in 98% positive HLA-I (MIF 2288), 98% positive ICAM-1 (MIF 1132), and 95% positive HLA-II (MIF 287). The results for the cells incubated with IFN-gamma protein were similar to those for the transduced line. Importantly, the enhanced expression was maintained for several days after irradiation and cryopreservation. Expression of the URO tumor markers was not affected. Protein-treated RCC targets showed superior CTL lysis compared with untreated cells. Our results show that IFN-gamma protein incubation in vitro enhances expression of important immune recognition molecules to levels expressed by transduced cells. Increased expression may enhance tumor recognition by the hosts immune system, as in the case of tumor cell vaccines. There may be no advantage to IFN-gamma transduction over in vitro incubation with IFN-gamma protein.


In Vitro Cellular & Developmental Biology – Animal | 2000

Characterization of cancer cell lines established from two human metastatic breast cancers

Shankar K. Nayak; Surabhi Kakati; Shashi R. Harvey; Colin C. Malone; Andrew N. Cornforth; Robert O. Dillman

SummaryCell lines are valuable resources for the study of the malignancy and potential therapy of human breast cancer. A major problem with adapting fresh breast tumor specimens to grow in vitro is contamination by fibroblasts. Previously, we have reported a technique to overcome this problem (Nayak, S. K; Dillman, R. O. Clin. Biotechnol. 3:237–242; 1991). We have recently established two new breast cancer cell lines, HH315 and HH375, that were derived from abdominal and supraclavicular lymph node metastases from two patients. They were characterized by (1) growth kinetics; (2) staining with monoclonal antibodies (MoAbs) to cytokeratin-19, epithelial membrane antigen (EMA), anticarcinoembryonic antigen (CEA), breast cancer antigen 1 (BRST-1), breast cancer antigen 2 (BRST-2), Her2/neu, and p53; (3) expression of domains of urinary plasminogen activator (uPA), neural cell adhesion molecule (NCAM), and haptoglobin (Hp) (Harvey et al., 1997); and (4) karyotypic analysis. Growth kinetic studies showed that doubling times for both lines ranged from 48 to 96 h. These two cell lines were found to have characteristics of the metastatic breast cancer cells. Both lines stained positive with MoAbs to cytokeratin-19 and EMA, thus confirming their epithelial origin. They also strongly reacted with the pan-breast carcinoma MoAbs BRST-1 and BRST-2, and carcinoembryonic CEA MoAb. Both cell lines overexpressed the oncogene proteins Her2/neu and p53. The tumor cells were negative for estrogen and progesterone receptors. HH315 cells were poorly differentiated, whereas the HH375 cells exhibited adenocarcinoma morphology. Both cell lines showed intense cell surface and some cytoplasmic staining for uPA, NCAM, and Hp domains, which is a characteristic of malignant neoplasms (Harvey et al., 1997). The HH375 cell line showed two cell types, of which 60% were hyperdiploids with 60–70 chromosomes and 5–10 marker chromosomes. The remaining cells were polyploid with more than 200 chromosomes. Cell line HH315 consisted of only a polyploid population. These cell lines may be useful in breast cancer research.


Cancer Biotherapy and Radiopharmaceuticals | 2003

Treatment of Human Solid Malignancies with Autologous Activated Lymphocytes and Cimetidine: A Phase II Trial of the Cancer Biotherapy Research Group

Robert O. Dillman; Gamini Soori; Carol DePriest; Shankar K. Nayak; Linda D. Beutel; Patric M. Schiltz; Cristina de Leon; Audrey A. O'Connor

OBJECTIVE The Cancer Biotherapy Research Group conducted a clinical trial to verify encouraging reports of antitumor activity of autolymphocyte therapy. PATIENTS AND METHODS Patients with a variety of advanced solid malignancies underwent an initial leukapheresis procedure to collect about 5 x 10(9) autologous lymphocytes that were stimulated in vitro for 3 days with anti-CD3 monoclonal antibody in the presence of indomethicin and cis-retinoic acid to obtain media that was frozen in aliquots. This media contained significant amounts of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon-gamma, and IL6, but no IL-2. Subsequently patients underwent up to 6 monthly leukaphereses to collect 2-5 x 10(9) autologous lymphocytes that were incubated in vitro for 6 days in the cryopreserved media containing autologous lymphokines, resulting in a cell population enriched for noncytotoxic T-helper lymphocytes. These were administered intravenously monthly for up to 6 months with daily oral cimetidine at a dose of 600 mg po qid, which was given throughout the treatment period. Tumor response was assessed every 2 months. RESULTS There were 47 patients (25 women and 22 men) with a median age of 55 years (range 31-79). One hundred seventy four treatments were delivered and were well tolerated. A mean of 2.05 +/- 1.46 (range 0.82-12.8 x 10(9)) cells were infused. Eighty-five percent received two or more doses; 19% received six doses. Objective tumor responses were observed in 1/15 renal cell, 1/13 colorectal, 0/6 breast, 0/5 lung, 0/2 gastric, 0/2 sarcoma, 0/1 pancreas, 0/1 prostate, 0/1 melanoma, and 0/1 eccrine. Forty-three patients have died. Median survival was 8.8 months, 1-year survival 35%, and 2-year survival 15%. CONCLUSION This complex treatment program was feasible. Infusion of these cells was well tolerated. Some antitumor activity was seen in patients with renal cell cancer and colorectal cancer.


Cancer Biotherapy and Radiopharmaceuticals | 2001

Short-Term Tumor Cell Lines from Breast Cancer for Use as Autologous Tumor Cell Vaccines in the Treatment of Breast Cancer

Robert O. Dillman; Linda D. Beutel; Cristina de Leon; Shankar K. Nayak

OBJECTIVE We tried to establish short-term cultures of autologous tumors from patients with breast carcinoma for potential use as active specific immunotherapy (i.e., autologous vaccine) after resection of primary breast cancer, and/or for the treatment of metastases. METHODS Between 10/90 and 12/99 the cell biology laboratory of the Hoag Cancer Center attempted to establish short-term tumor cell lines from 115 breast cancer specimens from 56 primary breast lesions, 17 axillary nodes, 14 other lymph node/soft tissue sites, 10 chest wall recurrences, and 6 thoracentesis of malignant pleural effusions. Success was defined by growth of 5 x 10(7) viable cells whose malignant nature and breast cancer origin was confirmed by histology of the submitted tissue, cell morphology and antigenic phenotyping. Variables associated with successful growth of short-term cell lines were examined. RESULTS Expansion to 5 x 10(7) cells was achieved for only 8/115 samples [7%] including two from chest wall recurrences, and one each from a supraclavicular node, an umbilical node, liver, omentum, and pleural fluid. Two of the successful cell lines were established from tissue that originally had been cryopreserved; the others were initiated from fresh tumor. The success rate was better from regional/distant metastases 7/55 (13%) compared to primary tumors 1/56 (1.8%) (p = 0.063). The success rate for tumors harvested at Hoag Hospital was 4/97 (4%) compared to 4/14 from (31%) distant sites, but all but one of the tumors from a distant geographic site was a metastatic lesion. Tumor cell lines were successfully established from metastatic lesions ranging in size from < 1.0 g to 19 g. Four patients were treated with their autologous vaccine in the setting of chemotherapy-refractory metastatic disease without any significant toxicity. CONCLUSIONS We were unable to establish short-term cell lines for most patients with primary or metastatic breast cancer using this methodology. However, two long-term cell lines have been established and characterized. Treatment with the autologous irradiated cell product was not associated with acute toxicity.

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