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Adjuvant high-dose therapy with peripheral blood stem cell support for patients with high-risk breast cancer.

We report on the efficacy and toxicity of a sequential high-dose therapy with peripheral blood stem cell (PBSC) support in 107 patients with high-risk stage II/III breast cancer. There were 90 patients with more than 9 tumour-positive axillary lymph nodes. An induction therapy of two cycles of ifosfamide (total dose, 7,500 mg/m(2)) and epirubicin (120 mg/m(2)) was given, and PBSC were harvested during granulocyte colony-stimulating factor (G-CSF)-supported leukocyte recovery following the second cycle. The PBSC-supported high-dose chemotherapy consisted of two cycles of ifosfamide (total dose 12,000 mg/m(2)), carboplatin (900 mg/m(2)) and epirubicin (180 mg/m(2)). Patients were autografted with a median number of 4.1 x 10(6) CD34+ cells/kg (range 1.9-26.5 x 10(6)), resulting in haematological reconstitution within approximately 2 weeks following high-dose therapy. The toxicity was moderate in general, and there was no treatment-related toxic death. Twenty-nine patients (27.1% of all patients) relapsed between 3 and 46 months following the last cycle of high-dose therapy (median 15 months). The probability of disease-free and overall survival at 3 years was 56% and 83%, respectively. A multivariate analysis showed that patients with stage II disease had a significantly better probability of disease-free survival (71%) in comparison with patients with stage III disease (30%). The probability of disease-free survival was also significantly better for patients with oestrogen receptor-positive tumours (62%) compared with patients with receptor-negative ones (40%). In conclusion, sequential high-dose chemotherapy with PBSC support can be safely administered to patients with high-risk stage II/III breast cancer. Further intensification of the therapy including the addition of non-cross-resistant drugs or immunological approaches may be envisaged for patients with stage III disease and hormone receptor-negative tumours.

Adult↗

HER2 overexpression as a prognostic factor in metastatic breast cancer patients treated with high-dose chemotherapy and autologous stem cell support.

We retrospectively evaluated the predictive and prognostic role of HER2 expression in 44 metastatic breast cancer (MBC) patients treated with high-dose consolidation chemotherapy (HDCT) and autologous stem cell support after induction chemotherapy (IC) with six courses of epirubicin+paclitaxel (22 patients) or gemcitabine+epirubicin+paclitaxel (22 patients). HER2 expression was evaluated by an immunohistochemical method (Herceptest, Dako). A total of 13 patients (29.5%) showed a HER2 overexpression (score 3+). After IC, nine patients were in complete response (CR), 30 in partial response (PR), and five in stable disease (SD); after HDCT, 20 (45.5%) obtained a CR, and 23 were in PR, for a conversion rate of 48.5%. Conversion rate for HER2-positive patients was 87.5 vs 37% for HER2-negative patients (P=0.018). The median progression-free (PFS) and overall survivals (OS) were 17.6 (95% CI 13.2-22.0) and 44 (95% CI 25.9-62.3) months, respectively. Patients with HER2 overexpression experienced a significantly (P=0.0042) shorter median PFS (15.3 months, 95% CI 11.1-19.5) compared to HER2-negative patients (21.3 months, 95% CI 14.3-28.4). The median OS was 27.6 months (95% CI 4.5-50.7) in HER2-positive patients and 50.3 months (95% CI 38.7-62.0) in HER2-negative patients (P=0.345). These results indicate that HER2 overexpression predicts a worse outcome for patients with MBC treated with HDCT, despite the high CR rate obtained in this subset of patients.

Adult↗

Dosimetry-based therapy in metastatic breast cancer patients using 90Y monoclonal antibody 170H.82 with autologous stem cell support and cyclosporin A.

Radioimmunoconjugates of 170H.82 (m170), a panadenocarcinoma monoclonal antibody, are effective for imaging primary and metastatic breast cancer. To evaluate m170 as a targeting agent for therapy, we developed (111)In- and 90Y-2-iminothiolane-2-[p-(bromoacetamido)benzyl]-1,4,7,10 tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-m170 immunoconjugates with 99% purity by molecular sieving and immunoreactivity comparable to unmodified antibody. (111)In-m170 pharmacokinetic studies were performed prior to each therapy to determine the maximum dose of 90Y-m170 that could be administered without exceeding a limit of 800 rad to the liver, lungs, or kidneys or 250 rad to the whole body or bone marrow for each of three cycles of treatment. Peripheral blood stem cells (PBSCs) were harvested and cyclosporin A (5 mg/kg twice daily) was administered as strategies to ameliorate myelosuppression and prevent the development of HAMA, respectively. An (111)In imaging/pharmacokinetic study was performed, and the 90Y dose was calculated and administered. The liver was the 90Y dose-limiting organ. The mean and range of calculated doses (in rad/mCi) for the five patients evaluated were as follows: whole body, 2.3 (2.1-2.4); liver, 17.8 (12.7-22.2); lung, 6.4 (4.8-7.2); kidney, 6.9 (6.3-11.5); marrow, 3.6 (1.9-4.4); and tumors (n = 25), 71.5 (14.1-141.5). Of the three patients treated, with doses of 37, 54, and 57 mCi of 90Y, one had a partial response, one had measurable tumor reduction but less than a partial response, and one had stable disease for more than 1 month. PBSCs prevented prolonged myelosuppression. The therapeutic responses, coupled with an absence, thus far, of significant adverse sequelae, suggest that this dosimetry-based approach combined with PBSCs may lead to effective therapy when higher 90Y doses are reached.

Adult↗

The MicroRNA pathway plays a regulatory role in stem cell division.

One of the key characteristics of stem cells is their capacity for self-renewal for long periods of time. In this respect, stem cells are similar to cancer cells, which also have the ability to escape cell cycle stop signals. Therefore, a critical question in stem cell and cancer biology is how cell division is regulated in these cell types. In this review, we summarize recent progress and describe future challenges to understanding the role the microRNA pathway plays in regulating mechanisms controlling stem cell division.

Animals↗

High dose chemotherapy and peripheral blood stem cell transplantation for high risk primary breast cancer: a single center experience in Thailand.

Twenty patients with high risk primary breast cancer underwent a high dose chemotherapy program at Ramathibodi Hospital, Bangkok. Eligible patients included 21 women who had a histological diagnosis of breast cancer with more than 10 axillary lymph nodes involved. The patients first underwent modified radical mastectomy, followed by conventional doxorubicin containing adjuvant chemotherapy, before entering the treatment program. Peripheral blood stem cells were mobilized with cyclophosphamide and G-CSF and were harvested by leukapheresis. High dose chemotherapy consisted of cyclophosphamide 5,625 mg/m2, cisplatinum 165 mg/m2 and carmustine (BCNU) 600 mg/m2 were subsequently given, followed by infusion of the harvested peripheral blood stem cells. The median duration of cytopenia after transplantation was 8 days (range 7-12). The median expense for the transplantation, in addition to the cost of mastectomy and conventional chemotherapy, was 224,396 Baht (approximately US $5,350). Three out of the first four patients developed interstitial pneumonitis within three months after transplantation. There was one fatal case which was the only regimen related mortality. BCNU was then reduced to 450 mg/m2 and lung complications were markedly reduced afterwards. The median follow up time was 37 months with a median disease free survival of 38 months and overall survival of four years at 84%.

Adult↗

Demonstration of the stem cell nature of clonogenic tumor cells from lung cancer patients.

The tumor cell colony-forming efficiency in soft agarose was evaluated in 190 specimens obtained from patients with either small cell carcinoma of the lung (SCCL) or adenocarcinoma of the lung (ACL). Tumor cell colony formation was observed in 45 out of 53 (84%) specimens containing cytopathologically identifiable SCCL tumor cells obtained from a variety of metastatic sites. Tumor cell colony formation was also observed in 6 out of 10 specimens containing ACL tumor cells. The colony-forming efficiency for these lung cancer specimens ranged from 0.003 to 0.72% per nucleated cell plated and from 0.05 to 1.5% per tumor cell plated. There were no differences in plating efficiency for SCCL and ACL. The tumor cell origin of the cells in the agarose colonies was confirmed by cytologic examination, flow cytometric DNA content analysis, and electron microscopy examination. The 'stem cell' nature was demonstrated by the ability of colonies to form typical SCCL or ACL tumors when inoculated into athymic nude mice. In addition, continuous tumor cell lines were established from several specimens forming tumors in nude mice. These data confirm the tumor cell origin and 'stem cell' nature of lung cancer cell colonies growing in soft agarose. Whether the low colony-forming efficiency represents a property inherent in the tumor cells, or a defect in the culture system, remains to be determined.

Adenocarcinoma↗

Identification of differentiating neural progenitor cell markers using shotgun isobaric tagging mass spectrometry.

The use of neural precursor cells (NPCs) represents a promising repair strategy for many neurological disorders. This requires an understanding of the molecular events and biological features that regulate the self-renewal of NPCs and their differentiation into neurons, astrocytes, and oligodendendrocytes. In this study, we have characterized the proteomic changes that occur upon differentiation of these cells using the novel iTRAQ labeling chemistry for quantitative mass spectrometry. In total, 55 distinct proteins underwent expression changes during NPC differentiation. This included 14 proteins that were identified by our previous two-dimensional difference gel electrophoresis (2D-DIGE) analysis of differentiating mouse neurospheres. The importance of the iTRAQ approach was demonstrated by the identification of additional proteins that were not resolved by the 2D-DIGE technology. The proteins identified by the iTRAQ approach included growth factors, signaling molecules, proliferating cell-specific proteins, heat shock proteins, and other proteins involved in the regulation of metabolism and the transcriptional and translational machinery. Further characterization of the identified proteins should provide greater insight into the mechanisms involved in regulation of neurogenesis in the adult central nervous system and potentially that of other proliferating cell types, including peripheral stem cells or cancer cells.

Amino Acid Sequence↗

The role of sialomucin CD164 (MGC-24v or endolyn) in prostate cancer metastasis.

BACKGROUND: The chemokine stromal derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 have been demonstrated to be crucial for the homing of stem cells and prostate cancers to the marrow. While screening prostate cancers for CXCL12-responsive adhesion molecules, we identified CD164 (MGC-24) as a potential regulator of homing. CD164 is known to function as a receptor that regulates stem cell localization to the bone marrow. RESULTS: Using prostate cancer cell lines, it was demonstrated that CXCL12 induced both the expression of CD164 mRNA and protein. Functional studies demonstrated that blocking CD164 on prostate cancer cell lines reduced the ability of these cells to adhere to human bone marrow endothelial cells, and invade into extracellular matrices. Human tissue microarrays stained for CD164 demonstrated a positive correlation with prostate-specific antigen levels, while its expression was negatively correlated with the expression of androgen receptor. CONCLUSION: Our findings suggest that CD164 may participate in the localization of prostate cancer cells to the marrow and is further evidence that tumor metastasis and hematopoietic stem cell trafficking may involve similar processes.

Bone Marrow Neoplasms↗

Stem cell transplantation: past, present and future.

The early attempts at human allogeneic marrow transplants in the 1950's and 1960's were largely unsuccessful. The probability of success has improved steadily in the past two decades. Cure rates now range from 90% for non-malignant diseases transplanted early to 15% for patients with advanced leukemia. Most marrow transplants have involved an HLA matched sibling donor but, more recently, a matched unrelated volunteer marrow donor can be found for many patients without a family donor. Current research is focused on new preparative regimens for elimination of malignant cells, better prevention of graft-versus-host disease, and the use of hematopoietic growth factors and cytokines. Autologous transplants, which use the patient's own marrow, are increasing, particularly for breast cancer. The hematopoietic stem cells are responsible for marrow regeneration after a transplant. Sufficient numbers of stem cells for transplantation can now be obtained from the peripheral blood after mobilization of these cells by chemotherapy or hematopoietic growth factors. Transplants can also be achieved using stem cells obtained from cord blood at the time of delivery, tissue typed, and cryopreserved for later use. A variety of technological advances has reduced the hospitalization time for transplant patients with a corresponding saving in cost.

Bone Marrow Transplantation↗

The role of stem cells and gap junctions as targets for cancer chemoprevention and chemotherapy.

Since carcinogenesis is a multi-stage, multi-mechanism process, involving mutagenic, cell death and epigenetic mechanisms, during the "initiation/promotion/and progression" phases, chemoprevention must be based on understanding the mechanism(s) of each phase. Prevention of each phase could reduce the risk to cancer. Because reducing the initiation phase to a zero level is impossible, the most effective intervention would be at the promotion phase. Assuming the "target" cells for carcinogenesis are the pluri-potent stem cells and their early progenitor or transit cells, chemoprevention strategies for inhibiting the promotion of these two types of pre-malignant "initiated" cells will require different agents. A hypothesis will be proposed that involves stem cells, which lack gap junctional intercellular communication (GJIC-) or their early progenitor daughter cells, which express GJIC+ and are partially-differentiated, if initiated, will be promoted by agents that either inhibit secreted negative growth regulators or by inhibitors of GJIC. Chemopreventing agents to each of these two types of initiated cells must have different mechanisms of action. Assuming stem cells are target cells for carcinogenesis, an alternative method of chemoprevention would be to reduce the stem cell pool. Anti-tumor promoter chemopreventive agents, such as green tea components, resveratrol, caffeic acid phenethylene ester, that either up-regulate GJIC in stem cells or prevent the down regulation of GJIC by tumor promoters in early progenitor cells, will be provided. Human pluri-potent stem cell systems, that can be induced to form 3-dimensional "organoid" structures, will be discussed as a more realistic model system to screen for relevant chemopreventive agents.

Animals↗

Patients with malignant lymphomas experience a higher rate of documented infections than patients with breast cancer after high-dose chemotherapy with autologous peripheral stem cell transplantation.

The influence of underlying disease on documented infections has rarely been addressed in patients treated with high-dose chemotherapy (HDCT) and subsequent autologous peripheral blood stem cell transplantation (PBSCT). Because autografting has been used most frequently for malignant lymphomas and breast cancer, we analyzed in a retrospective study the data of 100 consecutive adult patients with either malignant lymphomas (group A, n = 50) or breast cancer (group B, n = 50) treated with HDCT at a single institution. The number of autografted CD34+ cells was not statistically different in either group. In this paper, we show for the first time that there is a significant difference in clinically or microbiologically documented infections in these groups of patients: documented infections occurred in 30% of malignant lymphoma patients but only in 4% of breast cancer patients (P=0.001). Of all isolated microorganisms, 78% were gram-positive. Because most of the documented infections were due to staphylococci, further studies should prospectively evaluate preventive measures to reduce the high incidence of these infections. This is especially important for lymphoma patients, who can be regarded as a high-risk group concerning gram-positive bacteremia.

Adult↗

Wnt control of stem cells and differentiation in the intestinal epithelium.

The intestinal epithelium represents a very attractive experimental model for the study of integrated key cellular processes such as proliferation and differentiation. The tissue is subjected to a rapid and perpetual self-renewal along the crypt-villus axis. Renewal requires division of multipotent stem cells, still to be morphologically identified and isolated, followed by transit amplification, and differentiation of daughter cells into specialized absorptive and secretory cells. Our understanding of the crucial role played by the Wnt/beta-catenin signaling pathway in controlling the fine balance between cell proliferation and differentiation in the gut has been significantly enhanced in recent years. Mutations in some of its components irreversibly lead to carcinogenesis in humans and in mice. Here, we discuss recent advances related to the Wnt/beta-catenin signaling pathway in regulating intestinal stem cells, homeostasis, and cancer. We emphasize how Wnt signaling is able to maintain a stem cell/progenitor phenotype in normal intestinal crypts, and to impose a very similar phenotype onto colorectal adenomas.

Animals↗

High-dose chemotherapy with hematopoietic stem cell support in patients with advanced epithelial ovarian cancer: analysis of 67 patients treated in a single institution.

BACKGROUND: Advanced ovarian carcinoma is a chemosensitive tumor, but its prognosis is poor with 20 to 30% 5-year survival using conventional therapy. Increasing doses of chemotherapy might improve the prognosis because of the dose-effect. MATERIALS AND METHODS: Between 1980 and 1994 at Institut Paoli-Calmettes, 67 patients with advanced ovarian cancer were treated with different alkylating agents-based regimens of high dose chemotherapy (HDC) and hematopoietic stem cell support (HSCS). The population was divided in 2 groups: a salvage group (n = 30) including initial conventional chemotherapy-refractory patients, and a consolidation group (n = 37) including patients whose disease was sensitive to classical first-line chemotherapy after debulking surgery. RESULTS: Toxicity was essentially hematological (severe aplasia) and digestive (mucositis). Four toxic deaths occurred related to infection during immunosuppression. In the salvage group, 9 out of 22 evaluable patients responded (41%), but the duration of responses was short (median range of 6 months) and the 2-year overall survival rate was 13%. In the consolidation group, 17 patients are still alive, 12 with progression with a median follow-up of 63 months. The 5-year disease-free survival rate was 32% while the 5-year overall survival rate was 46%. CONCLUSIONS: Toxicity of HDC with HSCS is acceptable for poor-prognosis patients. In the long term, this therapy is not beneficial for chemotherapy refractory patients, despite objective response rates better than the conventional treatment, confirming the dose-effect for alkylating agents in ovarian cancer. On the other hand, the results seem better than classical therapy in case of chemosensitive disease and should be confirmed prospectively in a larger cohort of patients.

Antineoplastic Agents, Alkylating↗

Endocrine treatment for breast cancers: biological rationale and current progress.

Endocrine therapy is a major treatment modality for the systemic management of breast cancer. In comparison with alternatives such as chemotherapy, hormone manipulations have the advantage of lower toxicity but suffer from the disadvantages of producing responses in only 30-40% of patients with metastatic disease and seldom being curative. Nevertheless in recent years there have been significant advances in the endocrine treatment of breast cancer which have stemmed from a better understanding of the sources from which breast tumours may be supplied with hormones, the mechanism by which hormones regulate tumour proliferation and the more accurate identification of hormone sensitive tumours. As a result agents such as antioestrogens, aromatase inhibitors. LHRH agonists have largely superseded surgical and radiological ablation of endocrine organs. The major reduction in morbidity associated with these medical regimes means that they are much more acceptable to patients and may be used as adjuvants to local treatment of the breast in patients with "earlier" stages of the disease. At the same time patients can now be offered rational treatment selected on the basis of tumour biology rather than on more empirical criteria. The aims of this review are to provide details of the research which has led to this progress in endocrine treatment of breast cancer and to put into perspective the prospects for further advances.

Aromatase Inhibitors↗