Infusion Of Tumor Cells Research Articles

Abstract 60: Altering tumor cell metabolism may contribute to the antitumor activity of ethyl pyruvate

Abstract Pyruvate, a key metabolite in cellular energy metabolism, is the end-product of glycolysis and the starting substrate for the TCA cycle which generates NADH and ATP during oxidative phosphorylation. According to the Warburg hypothesis, increased conversion of glucose to lactic acid associated with decreased mitochondrial respiration is a unique feature of tumors. We have previously shown that ethyl pyruvate (EP), the ethyl ester of pyruvate, significantly inhibits the growth of hepatic tumors. The mechanism of this anti-tumor effect is unclear, and here we hypothesized that EP alters tumor cell metabolism. We analyzed the bioenergetic phenotype of tumor cells by measuring cellular respiration and glycolysis rate using a novel real-time assessment of oxidative phosphorylation and glycolysis. METHODS: C57BL/6 mice were injected with 2×105 MC38 colorectal and PANCO2 pancreatic tumor cells via the portal vein. In vitro, 4x104 MC38 and PANCO2 cells/well were seeded into XF24 V7 microplates. Cells were pretreated with/without EP (5-10mM) for 60 minutes before measurement. The XF24 Analyzer (Seahorse Bioscience) was used to measure extracellular flux changes of oxygen consumption rate (OCR, measure of oxidative phosphorylation) and the rate of proton excretion into the media (extracellular acidification rate, ECAR, measure of glycolytic rate). RESULTS: Mice injected with MC38 and PANCO2 cells resulted in the growth of bulky tumors in the liver. EP (80 mg/kg ip) administered 30 minutes prior to infusion of tumor cells and continuing daily for 9 days significantly inhibited tumor growth in a dose-dependent fashion, with 80 mg/kg EP achieving >70% reduction in the number of tumor nodules in comparison to untreated animals. TUNEL staining demonstrated a marked increase in tumor cell apoptosis in EP-treated mice. MC38 and PANCO2 tumor cells had substantially different bioenergetic phenotypes. MC38 cells had lower basal OCR (148 ± 13 vs 434 ± 32 pmoles/min, p< 0.05) and higher basal ECAR than PANCO2 cells (56 ± 6 vs 8 ± 2 mpH/min, respectively, p< 0.05). Use of 2-deoxyglucose (2-DG) to block glycolysis significantly enhanced OCR in PANCO2 from 437 ± 50 to 1486 ± 154 pmoles/min but not in MC38, suggesting that MC38 cells are more dependent on glycolysis. EP enhanced mitochondrial cellular respiration (OCR) in MC38 and decreased basal ECAR significantly without observable changes in PANCO2 cells, suggesting a reversal of the Warburg phenomenon. SUMMARY: Altering tumor cell metabolism by increasing mitochondrial oxidative phosphorylation and decreasing glycolysis may contribute to the antitumor activity of EP. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 60.

Tumor Cell Contamination of Bone Marrow Harvest Products: Clinical Consequences in a Cohort of Advanced-Stage Breast Cancer Patients Undergoing High-Dose Chemotherapy

Patients undergoing high-dose chemotherapy (HDC) with autologous stem cell rescue (ASCR) may have tumor cells inadvertently infused if their stem cell product is tumor contaminated. We used an immunocytochemical (ICC) method to analyze 31 histologically negative bone marrow (BM) specimens taken from women with advanced-stage breast cancer at the time of BM harvest before HDC. All 31 patients were treated on one of three consecutive HDC protocols and received BM or BM and peripheral stem cells (PSC) as ASCR. Six of 26 evaluable patients had ICC-detectable contaminating tumor cells in their BM harvests. These 6 patients had a trend toward decreased overall survival compared with those patients without ICC-detectable tumor cells (17 months median versus 25+ months, p = 0.11, log rank test for those patients achieving complete response, CR, from HDC). The sites of relapse in the ICC-positive and ICC-negative groups were not notably different when analyzed for new sites versus previous sites of disease. Therefore, our retrospective analysis of a small cohort of patients suggests that the infusion of tumor cells in breast cancer patients undergoing HDC may confer a poor prognosis. Relapse patterns however suggest failure both in new sites and in sites of previous disease. Additional studies in expanded patient populations are needed to explore further the role of tumor cell infusion in ASCR and the possible clinical benefits of tumor cell removal procedures.

Transplantation of CD34+ Peripheral Blood Progenitor Cells After High-Dose Chemotherapy for Patients With Advanced Multiple Myeloma

A major potential problem of autologous transplantation in the treatment of advanced malignancy is the infusion of tumor cells. A multi-institutional study of purified CD34-selected peripheral blood progenitor cell (PBPC) transplantation was conducted in 37 patients with advanced multiple myeloma receiving myeloablative chemotherapy. Fourteen days after intermediate-dose cyclophosphamide, prednisone, and granulocyte colony-stimulating factor (G-CSF), a median of 3 (range, 2 to 5) 10-L leukaphereses yielded 9.8 x 10(8)/kg (range, 3.7 to 28.3) mononuclear cells. The adsorbed (column-bound) fraction contained 5.9 x 10(6) cells/kg (range, 1.6 to 25.5) with 4.65 x 10(6) CD34 cells/kg (range, 1.2 to 23.3). Using Poisson distribution analysis of positive polymerase chain reactions with patient-specific complementarity-determining region 1 (CDR1) and CDR3 Ig-gene primers, tumor was detected in leukapheresis products from 8 to 14 unselected patients and ranged from 1.13 x 10(4) to 2.14 x 10(6) malignant cells/kg. After CD34 selection, residual tumor was detected in only three patients' products. Overall, a greater than 2.7- to 4.5-log reduction in contaminating multiple myeloma cells was achieved. CD34 PBPCs were infused 1 day after busulfan (14 mg/kg) and cyclophosphamide (120 mg/kg), and granulocyte-macrophage colony-stimulating factor was used until hematologic recovery. The median time to both neutrophil and platelet recovery was 12 days (range, 11 to 16 days and 9 to 52 days, respectively). The median number of erythrocyte and platelet transfusions was 7 (range, 2 to 37) and 3 (range, 0 to 85), respectively. Patients receiving fewer than 2 x 10(6) CD34 cells/kg had significantly prolonged neutropenia, thrombocytopenia, and an increased red blood cell and platelet transfusion requirement. Thus, CD34 selection of PBPCs markedly reduces tumor contamination in multiple myeloma and provides effective hematopoietic support for patients receiving myeloablative therapy.

Human Hematopoietic Stem Cells: Potential Use as Tumor-Free Autografts After High-Dose Myeloablative Cancer Therapy

Human hematopoietic stem cells are rare cells residing within the marrow and peripheral blood of humans. These cells are capable of producing each of the myeloid and lymphoid cell types and have the ability to produce additional stem cells. The infusion of stem cells in a graft is responsible for hematopoietic reconstitution after the delivery of lethal irradiation and/or high dose chemotherapy. Stem cells have been extensively characterized, and their phenotype has been defined. Technologies have now been developed that permit the isolation of sufficient numbers of stem cells for their use as grafts during hematopoietic cell transplantation. Mobilized peripheral blood grafts obtained from patients with cancer are frequently contaminated with tumor cells. The isolation of stem cells from mobilized peripheral blood permits the creation of a potentially free tumor-free graft. Such tumor free autografts might prevent the infusion of tumor cells receiving curative myeloablative therapies and thereby improve the efficacy of autotransplantation strategies for patients with selected cancers.

Growth Enhancement of Established Tumors by Allogeneic Blood Transfusion in Experimental Animals and Its Amelioration by Leukodepletion: The Importance of the Timing of the Leukodepletion

We had reported previously (Blood 81:1880, 1993) that allogeneic blood transfusions (ABT) administered before the infusion of tumor cells in both inbred and outbred experimental animals promote tumor growth and that this effect can be ameliorated by leukodepletion. To better reproduce the human situation, we evaluated, in this present study, the effect of ABT in animals with established tumors using enumeration of pulmonary metastatic nodules as the end point. The role of allogeneic blood component transfusions in promoting tumor growth and the relative efficacy of prestorage versus poststorage leukodepletion of the ABT in preventing tumor growth enhancement were also evaluated. In an inbred murine animal model, C57Bl/6J mice were administered nonleukodepleted allogeneic (ABT), leukodepleted allogeneic (LD-ABT), or syngeneic (SBT) blood transfusions after the intravenous infusion of syngeneic methylcholanthrene-induced fibrosarcoma cells using two different protocols. A significant increase in the number of pulmonary nodules was observed in those mice that received ABT, in both protocols, compared to animals transfused with SBT or LD-ABT. Significantly higher numbers of pulmonary nodules were also seen in mice transfused with allogeneic buffy-coat leukocytes compared with mice that received either nonleukodepleted allogeneic plasma or LD-ABT. In an outbred animal (rabbit) model, recipient rabbits were administered either nonleukodepleted ABT, prestorage LD-ABT, poststorage LD-ABT, or SBT on days +4 and +9 after the infusion of syngeneic epithelial tumor cells. A significant increase in the number of pulmonary nodules was seen in rabbits that received nonleukodepleted ABT compared to animals transfused with SBT. Significantly lower numbers of pulmonary nodules were observed in rabbits that received prestorage LD-ABT compared to animals transfused with poststorage LD-ABT, but no significant difference was seen in rabbits that received poststorage LD-ABT compared with animals transfused with nonleukodepleted ABT. These studies show that ABT promote tumor growth of established animal tumors, that the ABT-induced tumor growth effect is related to the presence of donor allogeneic leukocytes, and that this effect can be ameliorated by prestorage leukodepletion. The present results also provide evidence for the lack of efficacy of poststorage leukodepletion in preventing ABT tumor growth promotion.(ABSTRACT TRUNCATED AT 400 WORDS)

Growth enhancement of established tumors by allogeneic blood transfusion in experimental animals and its amelioration by leukodepletion: the importance of the timing of the leukodepletion

We had reported previously (Blood 81:1880, 1993) that allogeneic blood transfusions (ABT) administered before the infusion of tumor cells in both inbred and outbred experimental animals promote tumor growth and that this effect can be ameliorated by leukodepletion. To better reproduce the human situation, we evaluated, in this present study, the effect of ABT in animals with established tumors using enumeration of pulmonary metastatic nodules as the end point. The role of allogeneic blood component transfusions in promoting tumor growth and the relative efficacy of prestorage versus poststorage leukodepletion of the ABT in preventing tumor growth enhancement were also evaluated. In an inbred murine animal model, C57Bl/6J mice were administered nonleukodepleted allogeneic (ABT), leukodepleted allogeneic (LD-ABT), or syngeneic (SBT) blood transfusions after the intravenous infusion of syngeneic methylcholanthrene-induced fibrosarcoma cells using two different protocols. A significant increase in the number of pulmonary nodules was observed in those mice that received ABT, in both protocols, compared to animals transfused with SBT or LD-ABT. Significantly higher numbers of pulmonary nodules were also seen in mice transfused with allogeneic buffy-coat leukocytes compared with mice that received either nonleukodepleted allogeneic plasma or LD-ABT. In an outbred animal (rabbit) model, recipient rabbits were administered either nonleukodepleted ABT, prestorage LD-ABT, poststorage LD-ABT, or SBT on days +4 and +9 after the infusion of syngeneic epithelial tumor cells. A significant increase in the number of pulmonary nodules was seen in rabbits that received nonleukodepleted ABT compared to animals transfused with SBT. Significantly lower numbers of pulmonary nodules were observed in rabbits that received prestorage LD-ABT compared to animals transfused with poststorage LD-ABT, but no significant difference was seen in rabbits that received poststorage LD-ABT compared with animals transfused with nonleukodepleted ABT. These studies show that ABT promote tumor growth of established animal tumors, that the ABT-induced tumor growth effect is related to the presence of donor allogeneic leukocytes, and that this effect can be ameliorated by prestorage leukodepletion. The present results also provide evidence for the lack of efficacy of poststorage leukodepletion in preventing ABT tumor growth promotion.(ABSTRACT TRUNCATED AT 400 WORDS).

Ocular and cerebral metastases in the VX2 rabbit tumor model: contrast-enhanced MR imaging.

Ocular and cerebral metastases developed after the inoculation of a VX2 tumor cell suspension into the internal carotid artery of 15 rabbits. The hematogenous spread of tumor cells resulted in ocular metastases in 13 of 15 animals (86.7%) and cerebral system metastases in 14 of 15 animals (93%). Magnetic resonance (MR) imaging with Gd-DTPA demonstrated early disruption of the blood-ocular barrier and blood-brain barrier 5-7 days after infusion of tumor cells. Quantitative assessment of contrast enhancement revealed a mean increase in signal intensity of 145% +/- 51% in the anterior chambers, 102% +/- 70% for choroidal metastases, and 51% +/- 29% for central nervous system (CNS) metastases. These results indicate that contrast-enhanced MR imaging can be used to demonstrate a loss of blood-ocular barrier integrity that is similar to the breakdown of the blood-brain barrier associated with metastatic tumors to the CNS and eye.