Recently, micronucleus assay is expected to be one of the radiosensitivity tests. The usefulness of micronucleus assay was compared with MTT assay and clonogenic assay using 5 human derived urological cancer cell lines, NBT-2, T24, PC3, OS-RC-2, and RERF-LC-AI in vitro. The correlation between the results in vitro assay and the radiation effects of nude mouse in vivo was investigated.

High-dose chemotherapy with hematopoietic support has been expected to improve the survival of advanced ovarian cancer patients in recent years. An essential component of such treatment has been the ability to collect and reinfuse a large number of peripheral blood stem cells (PBSCs) following high dose therapy. This study was designed to determine which clinical and hematological factors would be better indicators to collect the proper volume of PBSCs. Thirteen patients received a total of 24 courses of induction chemotherapy and 69 of apheresis. We usually mobilized stem cells using CEP chemotherapy (cisplatin 50-70 mg/m2, epirubicin 50 mg/m2 and cyclophosphamide 1.5 g/m2) with G-CSF and CEE regimen (cyclophosphamide 2.0 g/m2, epirubicin 50 mg/m2, and etoposide 50 mg/m2) as a salvage for mobilization. We obtained an average 5 x 10(6)/kg of CD34+ cells for 3 days as one course. The number of CD34+ cells collected significantly depended on the platelets and reticulocytes on the first day of apheresis, but not a nadir of WBCs. It is concluded that apheresis should be started on recovery of WBCs to 5,000-10,000/microliters, of immature granulocytes to > or = 10% and of reticulocytes to > or = 20%. This study confirmed the feasibility of collecting enough PBSCs to use standard chemotherapy of ovarian cancer patients.

The collection of peripheral blood stem cells (PBSC) is a crucial step for successful PBSC transplantation. Routine hematological parameters utilized for predicting the optimal timing of collection include white blood cell (WBC) counts, high fluorescence ratio (HFR) of reticulocytes, and platelet counts. We compared these parameters with the CD34-positive rates in the peripheral blood. In regimen with high-dose chemotherapy where the WBC count at nadir was lower than 1,000/microliter, we found that the maximum mobilization of PBSC was observed on the day when the WBC count reached 10,000/microliter. This coincidence was within about one day (mean 0.44, standard deviation 0.53). However, the reliability of the WBC count as a marker of PBSC mobilization varied among different harvest regimens. In the regimen with regular-dose chemotherapy where the WBC count at nadir was above 1,000/microliter, we could not find such a tight coincidence between the WBC count and PBSC mobilization. These results suggested that, in some situations, the measurement of the CD34-positive rate is mandatory for an efficient PBSC collection. We also found that the number of CD34-positive cells in the peripheral blood correlated (x) well to the amount of the CD34-positive cells actually harvested (y) (y = 0.524x + 0.249, r = 0.787). Thus, rapid fluorescence activated cell sorter (FACS) analysis of peripheral CD34-positive rates seemed to be extremely useful to predict the yield of PBSC collection.

Harvest of peripheral blood stem cells (PBSC) was performed 57 times in 17 lung cancer patients after standard-dose chemotherapy (cisplatin, etoposide) supplemented with granulocyte-colony stimulating factor (G-CSF). In every case, more than 1.5 x 10(6)/kg CD 34+ cells were collected by 2-5 apheresis. Statistical significance was noted between peripheral leukocyte counts (WBC) and collected CD 34+ cell counts (p = 0.0298), between peripheral platelet counts and collected CD 34+ cell counts (p = 0.0009), and between the peripheral immature granulocyte ratio and collected CD 34+ cell counts (p < 0.0001). Because of the remarkable relationship between collected CD 34+ cell counts and peripheral WBC counts, peripheral platelet counts and the peripheral immature granulocyte ratio, these parameters were useful for determining the correct timing of PBSC harvest.

Five patients with metastatic testicular cancer of advanced extent according to the Indiana University criteria were enrolled into this study. All tumors were non-pretreated non-seminomas. Initially all patients were treated with standard dose etoposide, ifosfamide and cisplatin (VIP) regimen. The response of two cycles of VIP was evaluated by tumor markers and diagnostic imagings. Two of the five patients showed a good response to VIP and subsequently achieved a pathological complete response (pCR) following surgical resection of residual masses after 3 or 5 courses of VIP. However, they suffered from severe myelosuppression and underwent peripheral blood stem cell transplantation (PBSCT) following the final course of VIP. The remaining three patients unlikely to be cured by VIP underwent chemotherapy consisting of high dose ICE:ifosfamide (6-10 g/m2 over 4days) carboplatin (1,500 mg/m2 over 4 days), etoposide (1,600-2,400 mg/m2 over 4 days) combined with PBSCT. This regimen resulted in one partial response (PR) with marker-negative and two PR with marker-positive. Residual masses were removed in all three patients and viable tumor cells were found in two. Of the five patients enrolled, four patients (80%) remain disease-free with minimal follow-up of 20 months, and the remaining one died of cancer 10 months after PBSCT. No serious side effects or complications were encountered. This study shows that standard dose induction therapy of VIP followed by early salvage chemotherapy of high dose ICE with PBSCT is well tolerated and effective in the treatment of advanced poor-risk testicular cancer.

Bone resorption is a unique process which requires function of highly specialized cells, i.e., osteoclasts, Osteoclasts are terminally differentiated multinuclear cells that originate from multipotent hematopoietic stem cells and are closely related to the monocyte/macrophage lineage. Recent advances in molecular biological techniques and development of useful experimental systems both in vitro and in vivo have made it possible to identify several factors essential to osteoclast differentiation or function under physiological and/or pathological conditions. Such factors include transcription factors such as c-Fos and PU.1, cytokines such as IL-6 and TNF-alpha, and other various molecules such as tyrosine kinases and adhesion molecules. This review will focus on recent progress in our understanding of osteoclast biology.

Of 36 patients with malignant tumors who had been subjected to peripheral blood stem cell harvests (PBSCHs), 22 had undergone peripheral blood stem cell transplants (PBSCTs) since 1993. Flow cytometry recorded higher CD34+ cell yields in the PBSCHs of those patients with high white blood cell (WBC) counts as well as those who had been under intensive chemotherapy. Also, higher CD34+ cell yields were recorded in patients whose peripheral blood WBCs recovered more rapidly from their nadir state. WBC counts recovered rapidly in patients who received transfusions of at least 2.0 x 10(6) CD34+ cells/kg. However, patients with acute non-lymphocytic leukemia (ANLL) demonstrated a delayed recovery in their platelet counts following PBSCT. The mean disease-free survival rate and mean disease-free period were 60% and 12.8 months for the 5 patients with ANLL; and 100% and 11.3 months for the 4 patients with acute lymphocytic leukemia. These findings suggest PBSCT is a safe and effective treatment for patients with malignant tumors following high-dose chemotherapy, and can be performed in a private general hospital.

Acute myelocytic leukemia is characterized as a malignant disease with excessive accumulation of leukemic cells and deterioration of hematopoiesis. We studied the mechanism by which leukemic cells proliferated in patients. The indefinite growth of leukemic cells is supported by leukemic blast progenitors with a self-renewal capacity. Hematopoietic growth factors, such as granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3) or stem cell factor (SCF), have been revealed to stimulate the growth of leukemic blast progenitors. Furthermore, leukemic cells themselves produce and secrete hematopoietic factors that stimulate leukemic blast progenitors. The so-called autocrine growth mechanism has been postulated to play an important role in the pathophysiology of acute myelocytic leukemia. Leukemic cells show terminal differentiation under certain circumstances. For example, leukemic cells differentiate to neutrophils or macrophages in suspension culture. Leukemic cells of erythroleukemia (FAB M6) differentiate to granulocytic and erythrocytic lineages. The mechanisms involved in the proliferation and differentiation of leukemic cells in acute myelocytic leukemia are discussed in the article.

Telomerase activity was detected in germ cells, stem cells and cancer cells. In tumors of the ovary, an organ that contains germ cells, the authors examined availability to detect telomerase activity. Telomerase activity of malignant tumors was extremely high compared with that of normal ovaries and benign tumors. Strength and frequency of telomerase activity in malignant tumors was significant different from that in benign tumors. Telomere length tended to be smaller for malignant tumors of advanced stage, but no significant relationship between telomere length and telomerase activity and tumor stage could be recognized. Telomerase activity may be a useful marker for the diagnosis of ovarian tumors.

We described the localization of human telomerase RNA (hTR) expression in human gastric precancerous and cancerous lesions by using in situ mRNA hybridization. Diffusely high hTR expression was found in all carcinoma and adenoma tissues. Partially high hTR expression was seen in 75% hyperplastic polyps, 47% complete-type intestinal metaplasia and 21% incomplete-type intestinal metaplasia. All chronic gastritis without intestinal metaplasia possessed normal levels of hTR expression. The expression of hTR was heterogeneous and infiltrating lymphoid cells also expressed high levels of hTR expression. Taken together, overexpression of hTR due to stem cell hyperplasia is an early event of carcinogenesis of the stomach.

Telomerase, a ribonucleoprotein that maintains the ends of linear eukaryotic chromosomes, is expressed in the majority of malignant cells, while most normal somatic cells have no telomerase activity except germline and stem cells. Therefore, telomerase activity is considered one of important characteristics of tumors. In reviewing the possibility that conventional anticancer agents can partly perform their functions through modulation of telomerase. Several data including ours suggest that the down-modulation of telomerase activity along with inhibition by agents is the secondary event associated with cell death. Moreover, cells growth arrested at specific phase of cell cycle by agents still show the high level of telomerase activity. Since telomerase activity well correlates to the cell viability of treated cells, to study telomerase provides us a new implement to examine the sensitivity of cancer cells to agents.

We investigated on the rapid and easy method for the determination of peripheral blood stem cell (PBSC) using the immature information channel (IMI) of the automated hematology analyzer (SE-9000). The IMI channel provides information regarding immature leukocytes, including blast cells and immature granulocytes. CD34 positive cells, which are detected as the CD34 antigen on hematopoietic stem cells, were purified from the fractionated peripheral blood stem cell harvesting samples using Isolex. These purified CD34 positive cells accumulated in the gate corresponding to low Recurrent Frequency values which was presented on IMI channel analysis. Thus, the software for the IMI channel analysis to detect only the cells accumulated in this gate was developed (HPC program). The peripheral blood samples were collected from the subjects (22 cases) before and after chemotherapy. Using HPC program, the regression coefficient value between the ratio of IMI positive cells and CD34 positive cells in the peripheral blood samples was 0.81 (n = 122). As SE-9000 enables to determine the number of PBSC easily and rapidly, the measurement of IMI positive cells is clinically useful for the monitoring of the rise in PBSC after chemotherapy for mobilization.

Acute myelogenous leukemia (M2) with translocation of 8;21. Was diagnosed in 61-year-old man. He was successfully treated and obtained complete remission. After consolidation therapy, myeloid suppression and maturation arrest at the myelocyte level were recognized. Following intensive chemotherapy, he received rhG-CSF-mobilized peripheral blood stem cell transplantation (PBSCT) from an identical twin because he had life threatening infectious events and protracted myelosuppression. Transplantation of 2.5 x 10(6)/kg CD34+ cells resulted in a rapid normal tri-lineage hematologic reconstitution. Syngeneic PBSCT appears to be a substitute for syngeneic bone marrow transplantation in certain situations.

There is accumulating evidence that some substances which are originally transmitters affect neuronal development. Though noradrenaline (NA) containing neurons in the brain-stem innervate motoneurons as well as interneurons in the spinal cord, little is known about whether or not NA may play roles other than neurotransmission during development. Therefore, we have examined the effects of NA on developing neurons in the spinal cords of chick embryos. The dissociated cells were incubated with chemicals and the number of surviving cells was counted 2 days later. It was found that NA induced cell death in a dose dependent manner (EC50, 13 microM). Phentolamine, an alpha-adrenoceptor antagonist, prevented the cell death induced by NA (KD, 1.5 nM), whereas, alprenolol, a beta-adrenoceptor antagonist, did not. Furthermore, prazosin, an alpha 1-adrenoceptor antagonist, prevented the NA-induced cell death, but yohimbine, an alpha 2-adrenoceptor antagonist, did not. Dithiothreitol, an antioxidant, did not prevent NA-induced cell death. These results indicate that NA induces cell death in the developing neurons in the chick spinal cord through alpha 1-adrenoceptors.

Human cord blood provides a rich source of hematopoietic stem cells. On the basis of the finding, umbilical cord blood has been postulated to be an alternative and efficacious source of hematopoietic stem cells for allogeneic reconstitution. Early results of cord blood stem cell transplantation (CBSCT) show that the incidence and severity of graft versus host disease has been low in HLA mismatched transplants. Cord blood banking has several advantages such as lack of donor risk, indefinite storage, speed of donor search, viral safety. More than four hundred cases of unrelated CBSCT have been performed in the world. Kanagawa cord blood bank has been established on 1995 and other some private cord blood banks have been established in Japan. Eleven cases of unrelated CBSCT have been reported in Japan. Large scaled public cord blood bank should be established in near future.