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At least 793 records · Page 44Linked to original sources
PubMed2005

Paclitaxel-based high-dose chemotherapy with autologous stem cell rescue for relapsed germ cell cancer.

We evaluated the antitumor activity of tandem cycles of high-dose chemotherapy with autologous peripheral stem cell transplantation (aPSCT) in relapsed germ cell tumors by using high-dose paclitaxel, carboplatin, etoposide, and ifosfamide. Thirty-three patients were entered, and 31 underwent protocol therapy. Paclitaxel 350 mg/m2 (5 patients) or 425 mg/m2 (26 patients) by 24-hour continuous intravenous infusion was followed by 3 daily doses of carboplatin and either etoposide (cycle 1) or ifosfamide/mesna (cycle 2). The carboplatin dose had a calculated area under the curve of 7 mg-min/mL, and the daily dose of etoposide was 20 mg/kg (cycle 1). Ifosfamide 3 g/m2/d for 3 days (with mesna uroprotection) was substituted for etoposide in cycle 2. Each cycle was supported by granulocyte colony-stimulating factor-mobilized peripheral blood stem cells. Thirty-one patients were evaluable for response, toxicity, and long-term disease control. Two patients did not undergo aPSCT because of rapid disease progression. Nineteen patients received both cycles of aPSCT, 8 progressed after cycle 1, 3 refused the second cycle, and 1 died of fungal infection during cycle 1. Twelve patients remain relapse free at a median of 67 months from the initiation of therapy. Whereas the International Germ Cell Cancer Collaborative Group category at the time of initial diagnosis did not seem to predict outcome, the patient's probability of achieving durable remission was significantly associated with the Beyer prognostic score at the time of protocol entry. Regimens containing the most active agents in relapsed nonseminomatous germ cell tumors, including high-dose paclitaxel, are well tolerated and have promising activity even in patients with poor-risk features who do not achieve durable remissions with standard therapy. The Beyer prognostic system is a valuable predictor for patients undergoing aPSCT.

Adolescent↗
PubMed2000

Panel reactive antibodies in women with ovarian cancer undergoing high-dose chemotherapy with peripheral stem cell rescue: a case control study.

High-dose chemotherapy with stem cell support is associated with a period of profound thrombocytopenia. During periods of thrombocytopenia, alloreactive antibodies can limit the effectiveness of platelet transfusion. In this institution, women undergoing high-dose chemotherapy with stem cell support for treatment of their ovarian cancer seemed to have a high incidence of panel reactive antibodies (PRA). To evaluate this further, a case-control study was performed comparing pretransplant PRA values in 22 consecutive women undergoing high-dose chemotherapy as intensification therapy for their ovarian cancer and a control group of 51 women receiving similar or identical therapy for their breast cancer. Parity was similar in both groups. Nonparametric t-test comparison of the two groups demonstrated a significantly higher PRA value in women with ovarian cancer compared to those with breast cancer (p = 0.032). Platelet transfusions were more common in women with ovarian cancer as compared to those with breast cancer (5.45/pt and 4.79/pt), although this difference did not reach statistical significance. This finding suggests that alloimmunization may be a more frequent problem in patients with ovarian cancer than in women with breast cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Prospective evaluation of bone marrow signal changes on magnetic resonance tomography during high-dose chemotherapy and peripheral blood stem cell transplantation in patients with breast cancer.

RATIONALE AND OBJECTIVES: The authors evaluate bone marrow signal changes on magnetic resonance (MR) imaging during high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). METHODS: Fourteen patients with breast cancer without bone metastases underwent four sagittal MR imaging studies with T1-weighted, T2-weighted turbo spin-echo and inversion recovery sequences with short inversion time (STIR) of the lumbar spine: (1) during initial staging, (2) prior to high-dose chemotherapy after two cycles of induction chemotherapy, (3) early after PBSCT with a leukocyte exceeding 2000/microL, and (4) 6 to 8 weeks after PBSCT. Signal intensity ratios of averaged lumbar bone marrow to nucleus pulposus were measured and homogeneity was evaluated visually using a semiquantitative score. RESULTS: Compared with the initial finding (1): Signal intensity ratios were altered significantly at (2): T1-weighted: -22% +/- 14, P < 0.001; T2-weighted: -11% +/- 11, P < 0.01; STIR: +33% +/- 31, P < 0.01; Signal intensity ratios were altered significantly at (3): T2-weighted: -23% +/- 12, P < 0.001, STIR: -22% +/- 23, P < 0.01; and Signal intensity ratios were altered significantly at (4): only STIR: -16% +/- 19, P < 0.01. Homogeneity scores decreased at (3) for T1-weighted and STIR sequences (-1.6 +/- 0.5 to -2.0 +/- 0.7, P < 0.01 and -1.0 +/- 0.5 to -1.4 +/- 0.5, P < 0.01, respectively) and at (4) for the latter sequence (-1.0 +/- 0.5 versus -1.4 +/- 0.5, P < 0.01). At (4), T1-weighted images were less homogenous than initially in 3 of 14 (21%) patients. CONCLUSIONS: Magnetic resonance imaging demonstrates significant alterations of bone marrow composition during PBSCT but allows differentiation of benign therapy-related changes from those known in metastatic disease after completion of PBSCT.

Antineoplastic Agents↗
PubMed2001

Effect of induction chemotherapy and tandem cycles of high-dose chemotherapy on outcomes in autologous stem cell transplant for metastatic breast cancer.

We assessed the effect standard-dose induction chemotherapy and tandem cycles of high-dose chemotherapy (HDC) have on outcomes in metastatic breast cancer. One hundred and one women with metastatic breast cancer were enrolled in two non-randomized phase II studies. The first group of 64 patients (induction group) received four cycles of docetaxel 75 mg/m2 and doxorubicin 50 mg/m2. The next 37 patients did not receive induction (no induction group). Both groups received two (tandem) cycles of HDC. Blood-derived stem cells were collected after the first HDC cycle, processed using CD34+ cell selection and then reinfused after the second HDC cycle. Outcomes were compared between the two groups and also to patients participating in the Philadelphia (inter-group) randomized metastatic breast cancer transplant trial (PBT-01). Intent-to-treat analysis revealed no significant differences in complete response rates (37.5% vs 27%; P = 0.20), overall response (75% vs 71%), median progression free survival (PFS) (11.9 vs 8 months; P = 0.24) and overall survival (OS) (>36 vs 25 months; P = 0.16), in the induction vs no induction groups, respectively. Adjusting for differences in known baseline characteristics, induction group patients were found to have significantly longer PFS (P = 0.002), OS (P = 0.01) and more frequent conversion from a partial to complete response (58% vs < or = 13%, P < or = 0.0002) when compared with PBT-01 patients. Induction chemotherapy administered prior to tandem cycles of HDC does not appear to adversely affect outcomes in metastatic breast cancer patients. Outcomes in our induction group also compare favorably with those observed in PBT-01 and warrant further clinical investigation.

Adult↗
PubMed1984

Use of the human tumor stem cell assay to study chemotherapy sensitivity in cancer of the cervix.

Two questions concerning chemotherapy of cervical cancers are addressed in this study. 1) Can the human tumor stem cell assay identify active chemotherapeutic agents?; and 2) Can the human tumor stem cell assay predict which patient's tumors will demonstrate clinical responsiveness to chemotherapy? Sixty-seven of 76 cervical cancer specimens (88.2%) were grown in the human tumor stem cell assay, resulting in 159 separate drug assays. Based on the known activity of standard chemotherapeutic agents demonstrated in clinical trials, cisplatin, bleomycin, vincristine, and mitomycin C were chosen for testing. In vitro sensitivity patterns, seen at one-tenth of the peak plasma drug concentration, were similar to those seen in historic clinical trials. Retrospective correlations between in vitro drug sensitivity data and patient responses to chemotherapy are available from 13 patients, demonstrating clinically helpful predictive capabilities of the assay. Two conclusions were made: 1) The human tumor stem cell assay can determine single agent activity, which is often dose related; and 2) Useful correlations with clinical responses were observed.

Adenocarcinoma↗
PubMed2004

Stem cells and prenatal origin of breast cancer.

The hypothesis that in utero exposure to pregnancy hormones, notably estrogens, is related to the occurrence of breast cancer in the offspring has been examined in a number of epidemiological and experimental studies. Many studies have provided direct or indirect evidence that supports the hypothesis of an intrauterine component in the origin of breast cancer. Human studies to examine the underlying biological mechanisms, however, have been limited. We review the likely role of stem cells in hormone-mediated carcinogenic process, particularly as intermediate steps between in utero exposure to hormones and breast cancer. We summarize also studies related to the assumptions of the hypothesis concerning in utero exposure. We propose the use of stem cell potential as a measurable variable of the 'fertile soil', a term that has been used to characterize the consequences of fetal exposure to intrauterine environment. We conclude by outlining a feasible population-based study that measures stem cell potential to explore mechanisms mediating the relation between in utero exposure to pregnancy hormones and breast cancer risk in the offspring.

Breast Neoplasms↗
PubMed1999

[Two-step ultra high-dose chemotherapy with peripheral blood stem cell autotransplantation for refractory testicular cancer: a case report].

A 35-year-old male had advanced nonseminomatous germ cell tumor (stage IIIC, embryonal cell carcinoma) which proved refractory to conventional PVB combined chemotherapy. He was then treated with an ultra high-dose chemotherapy consisting of carboplatin (1.5 g/m2) and etoposide (1.3 g/m2), followed by the transplantation of peripheral blood stem cells (PBSCT) with a total of 1.9 x 10(5)/kg granulocyte colony-forming cells (CFU-GM). Because he developed lung metastasis, escalated doses of carboplatin (2.0 g/m2), and etoposide (1.8 g/m2) combined with cyclophosphamide (7.0 g/m2) were given with peripheral blood stem cell transplant of 3.2 x 10(5)/kg CFU-GM. He has remained free of any recurrence without maintenance therapy.

Adult↗
PubMed1983

Breast cancer as analyzed by the human tumor stem cell assay.

Patients with primary and recurrent carcinomas of the breast were studied by the human tumor stem cell assay to determine if (1) colonies would form from breast cancer specimens, (2) growth in the culture would equate with aggressiveness of disease, (3) the assay would yield specific information on drug responsiveness, and (4) the assay would yield nonspecific information on drug responsiveness. Colony counts ranged from 0 to 363. There was no significant difference in median colony counts by pathologic stage of disease or site. Among stage IV patients presenting for treatment with primary disease, those with colony counts greater than 10 had a mortality rate of 4.7/1000 person-days; there were no deaths among those with colony counts less than or equal to 10 (P = 0.042). Stage IV patients presenting with recurrent disease showed no association between colony counts and survival (P = 0.53). No significant relationship between colony counts and disease-free intervals was observed among stages I, II, and III patients (P = 0.10). Drug sensitivity in vitro was found in 14% of the cultures with colony counts greater than or equal to 30. The only complete clinical responses in stage IV patients occurred in two patients with 0 colony counts. These data demonstrate that colonies grow from breast cancer specimens, that colony formation in vitro may be related to aggressiveness of growth in vivo in patients presenting with stage IV disease, that drug sensitivity is demonstrated in few cultures, and that patients with metastatic disease who have complete response to systemic therapy may be identified by lack of growth in the culture.

Antineoplastic Agents↗
PubMed1996

Autocrine growth of small cell lung cancer mediated by coexpression of c-kit and stem cell factor.

At least 70% of small cell lung cancer (SCLC) tumors and tumor-derived cell lines coexpress the genes for stem cell factor (SCF) and its receptor, the c-kit proto-oncogene. To assess the impact of coexpression of the growth factor and receptor on SCLC growth, the NCI-H146 SCLC cell line, which expresses only SCF, was transfected with a c-kit expression vector. Kit protein immunoprecipitated from the transfected cells had a constitutive level of tyrosine phosphorylation, and these cells grew more vigorously in serum-free medium compared to control-transfected cells. This growth advantage could be blocked by the addition of the tyrosine kinase inhibitor herbimycin A. Growth of the c-kit-transfected cells could be further enhanced by the addition of bombesin or insulin-like growth factor-1, suggesting that the SCF/c-kit autocrine loop could function cooperatively with other SCLC autocrine loops. To further investigate the importance of this autocrine loop, a cell line that naturally coexpresses SCF and c-kit was transfected with a kinase-defective c-kit gene. Cells transfected with the defective gene showed a marked decrease in their ability to grow under growth factor-free conditions compared to cells transfected with the empty expression vector. Taken together, these studies demonstrate that the coexpression of the stem cell factor and c-kit genes is a major contributor to the growth factor independence of SCLC.

Bombesin↗
PubMed2001

Nonmyeloablative stem cell transplantation for the treatment of cancer and life-threatening nonmalignant disorders: past accomplishments and future goals.

Allogeneic bone marrow transplantation (BMT) or blood stem cell transplantation represents an important therapeutic tool for the treatment of otherwise incurable malignant and nonmalignant diseases. Until recently. autologous and allogeneic BMT or mobilized blood stem cell transplantation was used primarily to replace a malignant, genetically abnormal, or deficient immunohematopoietic compartment, and therefore highly toxic myeloablative regimens were considered mandatory for eradication of all undesirable host-derived hematopoietic elements. Our preclinical and ongoing clinical studies have indicated that more effective eradication of host immunohematopoietic system cells could be achieved by adoptive allogeneic cell therapy with donor lymphocyte infusion following BMT. Thus eradication of blood cancer cells, especially in patients with chronic myelogenous leukemia and less frequently in patients with other hematologic malignancies, can frequently be achieved despite complete resistance of such tumor cells to the maximum tolerated doses of chemoradiotherapy. Our cumulative experience suggests that graft vs leukemia (GVL) effects might be a useful tool for eradication of otherwise resistant tumor cells of host origin. Based on the cumulative clinical experience and experimental data in animal models of human diseases, it appears that induction of host vs graft tolerance as the first step may allow durable engraftment of immunocompetent donor lymphocytes, which may be used for induction of effective biologic warfare against host-type immunohematopoietic cells that need to be replaced, whether they are malignant, genetically abnormal, or self-reactive. Based on this rationale, we speculate that the therapeutic benefit of BMT may be increased by using safer conditioning as part of the transplantation procedure, with the goal of inducing host vs graft tolerance to enable subsequent induction of GVL, possibly graft vs tumor, or even graft vs autoimmunity effects, rather than attempting to eliminate host cells with hazardous myeloablative chemoradiotherapy. Our hypothesis suggests that effective BMT procedures might be accomplished without lethal conditioning of the host, using new, well-tolerated nonmyeloablative regimens, possibly minimizing immediate and late side effects related to myeloablative procedures. Recent clinical data suggest that effective BMT procedures may be accomplished with nonmyeloablative stem cell transplantation (NST) regimens, with no major toxicity. Thus new NST approaches may make BMT procedures safer for a spectrum of clinical indications in children and elderly individuals without lower or upper age limits, while minimizing procedure-related toxicity and mortality. Our cumulative data suggest that high-dose chemotherapy and radiation therapy may be successively replaced by more effective alloreactive donor lymphocytes, thus setting the stage for innovative therapeutic procedures with safer and more effective treatment of patients requiring BMT.

Animals↗
PubMed2002

Non-myeloablative stem cell transplantation for the treatment of cancer and life-threatening non-malignant disorders; past accomplishments and future goals.

Allogeneic bone marrow or blood stem cell transplantation (BMT) represents an important therapeutic tool for treatment of otherwise incurable malignant and non-malignant diseases. Until recently, autologous and allogeneic bone marrow or mobilized blood stem cells transplantation were used primarily to replace malignant, genetically abnormal or deficient immunohematopoietic compartment and therefore, highly toxic myeloablative regimen were considered mandatory for more effective eradication of all undesirable host-derived hematopoietic elements. Our preclinical and ongoing clinical studies indicated that much more effective eradication of host immunohematopoietic system cells could be achieved by adoptive allogeneic cell therapy with donor lymphocyte infusion following BMT. Thus, eradication of blood cancer cells, especially in patients with CML and less frequently in patients with other hematologic malignancies, could be frequently accomplished despite complete resistance of such tumor cells to maximally tolerated doses of chemoradiotherapy. Our cumulative experience suggested that graft versus leukemia (GVL) effects might be a useful tool for eradication of otherwise resistant tumor cells of host origin. Based on the cumulative clinical experience and experimental data in animal models of human diseases it appears that induction of host versus graft tolerance as step one, may allow durable engraftment of donor immunocompetent lymphocytes, which may be used for induction of effective biologic warfare against host-type immunohematopoietic cells that need to be replaced, malignant, genetically abnormal or self-reactive alike. Based on the aforementioned rationale, we speculated that the therapeutic benefit of BMT may be improved by using a safer conditioning as part of the transplant procedure, with the goal in mind to induce host versus graft tolerance to enable subsequent induction of GVL, possibly graft versus tumor or even graft versus autoimmunity effects, rather than attempt to eliminate host cells with hazardous myeloablative chemoradiotherapy. The latter hypothesis suggested that effective BMT procedure may be accomplished without lethal conditioning of the host, using new well tolerated non-myeloablative regimen, thus possibly minimizing immediate and late side effects related to myeloablative procedures considered until recently mandatory for conditioning of BMT recipients. Recent clinical data that will be presented suggests that effective BMT procedures may be accomplished with well-tolerated non-myeloablative stem cell transplantation (NST) regimen, with no major toxicity. Thus, new NST approaches may offer the feasibility of safer BMT procedure for a large spectrum of clinical indications in children and elderly individuals without lower or upper age limit, while minimizing procedure-related toxicity and mortality. Taken together, our cumulative data suggest that high dose chemotherapy and radiation therapy may be successively replaced by a more effective biologic tool, alloreactive donor lymphocytes, thus setting the stage for innovative therapeutic procedures for safer and more effective treatment of patients in need of BMT.

Autoimmune Diseases↗
PubMed2000

Importance of radiation therapy for breast cancer patients treated with high-dose chemotherapy and stem cell transplant.

PURPOSE: To determine local-regional failure rates in breast cancer patients treated with surgery and high-dose chemotherapy with stem cell transplant and to relate local-regional failure to the use and timing of radiation treatment. METHODS AND MATERIALS: We retrospectively reviewed the records of 165 breast cancer patients treated on institutional protocols with surgery and high-dose chemotherapy with stem cell transplant. All patients had either Stage III disease, 10 or more positive axillary lymph nodes, or 4 or more positive axillary lymph nodes following neoadjuvant chemotherapy. Twelve patients had inflammatory breast cancer. Thirteen patients treated with breast preservation and 5 patients who died from toxicity within 30 days of transplant were excluded from the analyses of local-regional recurrences. In the remaining 147 patients, 108 were treated with adjuvant radiation and 39 were not. The disease stage distribution for these two groups was comparable. The median follow-up for surviving patients was 35 months. RESULTS: The 3- and 5-year actuarial disease-free survival (DFS) for the entire group was 60% and 51%, respectively. The 5-year rates of freedom from isolated local-regional recurrence were 95% in the patients treated with adjuvant radiation and 86% in the patients who did not receive radiation (p = 0.014, log rank comparison). The 5-year rates of any local-regional recurrence as a first event (isolated recurrences plus those with simultaneous local-regional and distant recurrences) were 92% versus 82%, respectively for patients whose treatment did and did not include radiation (p = 0.038). We could not demonstrate a correlation of the timing of radiation with the risk of local-regional recurrence. CONCLUSIONS: These data indicate that high-dose chemotherapy does not negate the importance of radiation in optimizing local-regional control in patients with high-risk breast cancer. Given the results of recent randomized trials studying postmastectomy radiation, which show that improving local-regional control improves overall survival (OS), we believe that all breast cancer patients with high-risk primary breast cancer who are treated with high-dose chemotherapy with stem cell transplant should receive radiation as a component of their treatment.

Adult↗
PubMedDate not supplied

The use of bone marrow and peripheral blood stem cell transplantation in the treatment of cancer.

Since its first successful application 25 years ago, the clinical use of bone marrow and peripheral blood stem cell transplantation has increased dramatically. Transplantation allows for the administration of high doses of systematic chemotherapy and radiotherapy and confers an antitumor effect separate from the effects of chemotherapy. However,complications including toxicity of treatment, graft failure, and graft-versus-host disease exist. This article reviews the history and current use of bone marrow and peripheral blood stem cell transplantation and outlines new approaches for clinical application.

Bone Marrow Transplantation↗
PubMed1995

Very high-dose chemotherapy with autologous peripheral stem cell support in advanced ovarian cancer.

20 patients with stage III-IV ovarian cancer were submitted to induction chemotherapy (ICT) (40 mg/m2 cisplatin, days 1-4; 1.5 g/m2 cyclophosphamide, day 4; every 4 weeks for 2 cycles) followed by intensified CT (100 mg/m2 cisplatin, day 1; 650 mg/m2 etoposide, day 2; 1.8 g/m2 carboplatin by 24 h infusion, day 3). Haematological support consisted of autologous peripheral stem cells (APSC) and bone marrow (ABM) transplant (T) in 16 and 4 patients, respectively. All patients were evaluable for toxicity and 19 for pathological response (PR), one patient dying of systemic mycosis after ABMT. Severe (grade 3-4) non-haematological toxic effects were gastrointestinal (100%), neurological (10%) and hepatic (10%). PR was observed in 84% of patients (complete response 37%, partial response with microscopic residual disease 26%, partial response with macroscopic residual disease 21%). Five year overall survival was 60% and progression-free survival was 51% with 9 patients still disease-free (DFS). APSCT significantly reduced the duration of aplasia compared with ABMT, and toxicity was acceptable in those patients undergoing APSCT. The prolonged DFS in patients showing PCR suggests that this new approach may have a therapeutic impact.

Adenocarcinoma↗
PubMed1995

High-dose chemotherapy with autologous peripheral stem cell support in advanced ovarian cancer.

Twenty patients with advanced (stage III-IV), previously untreated ovarian carcinoma were treated by: (a) induction chemotherapy (40 mg/m2 cisplatin, days 1-4; 1.5 g/m2 cyclophosphamide, day 4; every 4 weeks for two cycles) followed by (b) intensification chemotherapy (100 mg/m2 cisplatin, day 1; 650 mg/m2 etoposide, day 2; 1.8 g/m2 carboplatin, day 3). Eligibility criteria further included: age less than 55 years, moderately good to poor tumour grade, macroscopic (> 0.5 cm) residual tumour. Autologous peripheral stem cells were recruited after the induction cycles and, to ensure haematological support, autologous bone marrow harvesting was routinely performed in the first 14 cases. Haematological support consisted of autologous peripheral stem cells and autologous bone marrow transplant in 16 and four patients, respectively. All patients are evaluable for toxicity and 19 for pathological response, one being dead of systemic mycosis 35 days after the autologous bone marrow transplant. Severe extra-haematological toxicities were the following: gastrointestinal (100%), neurological (10%), hepatic (10%). Pathological response was detected in 84% of cases (CR 37%, microscopic PR 26%, macroscopic PR 21%). Median follow-up times of 48 and 41 months have been reached respectively from enrolment and second-look. Four-year 62% overall and 57% progression-free survivals have been reached. Ten patients are still alive with NED (six of seven with CR, three of five with microscopic PR, and one of four with macroscopic PR). Autologous peripheral stem cell transplant significantly reduced the duration of aplasia compared with autologous bone marrow transplant, and toxicity was proved to be manageable in those patients undergoing autologous peripheral stem cell transplant. The prolonged disease-free survival in patients showing CR and microscopic PR suggests that further investigation on this new approach is worthwhile.

Adult↗
PubMed2005

Association of fetal hormone levels with stem cell potential: evidence for early life roots of human cancer.

Intrauterine and perinatal factors have been linked to risk of childhood leukemia, testicular cancer, and breast cancer in the offspring. The pool of stem cells in target tissue has been suggested as a critical factor linking early life exposures to cancer. We examined the relation between intrauterine hormone levels and measurements of stem cell potential in umbilical cord blood. Cord blood donors were 40 women, ages >/=18 years, who delivered, from August 2002 to June 2003, a singleton birth after a gestation of at least 37 weeks. We assayed plasma concentrations of estradiol, unconjugated estriol, testosterone, progesterone, prolactin, sex hormone binding globulin, insulin-like growth factor-I (IGF-I), and IGF binding protein-3. For stem cell potential, we measured concentrations of CD34(+) and CD34(+)CD38(-) cells and granulocyte-macrophage colony-forming unit (CFU-GM). We applied linear regression analysis and controlled for maternal and neonatal characteristics. We found strong positive associations between IGF-I and stem cell measures, 1 SD increase in IGF-I being associated with a 41% increase in CD34(+) (P = 0.008), a 109% increase in CD34(+)CD38(-) (P = 0.005), and a 94% increase in CFU-GM (P = 0.01). Similar associations were observed for IGF binding protein-3. Among steroid hormones, estriol and testosterone were significantly positively associated with CD34(+) and CFU-GM. These findings indicate that levels of growth factors and hormones are strongly associated with stem cell potential in human umbilical cord blood and point to a potential mechanism that may mediate the relationship between in utero exposure to hormones and cancer risk in the offspring.

Antigens, CD↗