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PubMed2006

Generation of a functional mammary gland from a single stem cell.

The existence of mammary stem cells (MaSCs) has been postulated from evidence that the mammary gland can be regenerated by transplantation of epithelial fragments in mice. Interest in MaSCs has been further stimulated by their potential role in breast tumorigenesis. However, the identity and purification of MaSCs has proved elusive owing to the lack of defined markers. We isolated discrete populations of mouse mammary cells on the basis of cell-surface markers and identified a subpopulation (Lin-CD29hiCD24+) that is highly enriched for MaSCs by transplantation. Here we show that a single cell, marked with a LacZ transgene, can reconstitute a complete mammary gland in vivo. The transplanted cell contributed to both the luminal and myoepithelial lineages and generated functional lobuloalveolar units during pregnancy. The self-renewing capacity of these cells was demonstrated by serial transplantation of clonal outgrowths. In support of a potential role for MaSCs in breast cancer, the stem-cell-enriched subpopulation was expanded in premalignant mammary tissue from MMTV-wnt-1 mice and contained a higher number of MaSCs. Our data establish that single cells within the Lin-CD29hiCD24+ population are multipotent and self-renewing, properties that define them as MaSCs.

Animals↗
PubMed2004

Randomized Phase II trial of two high-dose chemotherapy regimens with stem cell transplantation for the treatment of advanced ovarian cancer in first remission or chemosensitive relapse: a Southwest Oncology Group study.

OBJECTIVES: To evaluate response rates, progression-free survival (PFS), overall survival (OS), and toxicity of two high-dose chemotherapy regimens with stem cell rescue used to treat patients with recurrent or persistent stage III/IV ovarian cancer, with the goal of taking one forward into a Phase III comparison with conventional therapy. METHODS: Patients under 65 with clinically or pathologically persistent disease after initial chemotherapy or those relapsing >6 months after a complete remission (CR) were randomized to CMC carboplatin (1500 mg/m(2)), mitoxantrone (75 mg/m(2)), and cyclophosphamide (120 mg/kg)], or CTC: [cisplatin (165 mg/m(2)), thiotepa (600 mg/m(2)), and cyclophosphamide (5625 mg/m(2))] with stem cell rescue. RESULTS: Of 67 randomized, the 32 and 26 eligible in the CMC and CTC arms were matched including age (median 49), maximum tumor diameter, and disease status at transplant. Low-risk disease (maximum diameter disease <or= 0.5 cm and platinum sensitivity) was demonstrated in only approximately one-half of the patients. There were two treatment-related deaths in each arm. The median PFS was 13 and 8 months, respectively, for the CMC and CTC arms. The median OS was 29 and 22 months for the CMC and CTC arms. In a multivariate analysis of PFS, normal CA125 at transplant and CR to primary therapy were significant; for OS, normal CA125 and platinum sensitivity were significant. CONCLUSIONS: The CMC regimen was the superior regimen. However, few patients were long-term progression-free survivors. A clinical CR to primary therapy and a normal CA125, seen in a minority of patients, were requirements for a favorable outcome.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2004

Nonmyeloablative stem cell transplantation: reduced-intensity conditioning for cancer immunotherapy--from bench to patient bedside.

Despite major progress in treating hematologic malignancies and, to a lesser extent, metastatic solid tumors, much work remains ahead. With the anticancer potential of immunotherapy not yet fully exploited, patients with leukemia, malignant lymphoma, and other hematologic malignancies for which high-dose chemoradiotherapy is frequently recommended in conjunction with stem cell transplantation (SCT) can now benefit from the advantages of immunotherapy mediated by cytokines or alloreactive donor lymphocytes, while minimizing procedure-related toxicity and mortality. The feasibility of applying allogeneic cell-mediated immunotherapy in conjunction with allogeneic SCT following reduced-intensity conditioning, with minimal toxicity and no serious transplant-related complications, makes it possible to undertake such procedures on an outpatient basis as well as to offer an option for cure to elderly individuals and patients with less than optimal performance status. Being well tolerated, reduced-intensity transplants also offer a chance for cure to patients with otherwise resistant leukemia and malignant lymphoma who have relapsed after autologous SCT. Thus, the traditional obstacle of very high transplant-related toxicity and mortality due to multiorgan failure from cumulative toxicity of multiple anticancer agents and radiation therapy is overcome. Although immunotherapy mediated by allogeneic lymphocytes can be most effective, the immune potential of donor lymphocytes should be maximized by nonspecific or specific activation in vitro or in vivo, or both, for more effective eradication of resistant tumor cells, including in patients with bulky disease. More important is the challenge to target donor lymphocytes to the tumor and minimize their capacity to induce responses against normal host tissues, which frequently results in severe acute and chronic graft-versus-host disease (GVHD). Alternatively, donor lymphocytes should be eliminated as soon as tumor eradication is completed, or as soon as severe GVHD becomes prohibitive. Based on available experience, clinical application of innovative therapy, especially at the stage of minimal residual disease (MRD), may open new horizons for the treatment of malignancies considered until recently to be incurable. The feasibility of controlling cancer by targeted chemotherapy, best illustrated by the phenomenal activity of imatinib in patients with chronic myelogenous leukemia and, more recently, in gastrointestinal stromal tumors (including in patients fully resistant to all known anticancer agents) suggests that in the future, tumor-specific chemotherapy may represent the ultimate goal for achieving a stage of MRD with minimal multiorgan toxicity. Together, the combination of immunotherapy and targeted chemotherapy may provide the most logical approach for making real progress in controlling resistant hematologic malignancies and metastatic solid tumors.

Animals↗
PubMed2006

Ancestral telomere shortening: a countdown that will increase mean life span?

Like cells, all mammals have a limited life span. Among cells there are a few exceptions (e.g., immortal cells), among mammals not, even if some of them live longer. Many in vitro and in vivo studies support the consensus that telomere length is strongly correlated with life span. At the somatic cellular level, long telomeres have been associated with longer life span. A different situation can be seen in immortal cells, such as cancer, germ and stem cells, where telomeres are maintained by telomerase, a specialized reverse transcriptase that is involved in synthesis of telomeres. Irrespective of telomere length, if telomerase is active, telomeres can be maintained at a sufficient length to ensure cell survival. To the contrary, telomeres shorten progressively with each cell division and when a critical telomere length (Hayflick limit) is reached, the cells undergo senescence and subsequently apoptosis. In mammals, those with the longest telomeres (e.g., mice) have the shortest life span. Furthermore, the shorter the mean telomere length, the longer the mean life span, as observed in humans (10-14 kpb) and bowhead-whales (undetermined telomere length), which have the longest mean life span among mammals. Over the past centuries, human average life span has increased. The hypothesis presented here suggests that this continual increase in the mean life span could be due to a decrease of mean telomere length over the last hundreds years. Actually, the life span is not directly influenced by length of telomeres, but rather by telomere length - dependent gene expression pattern. According to Greider, "rather than average telomere length, it is the shortest telomere length that makes the biggest difference to a cell". In the context of fast-growing global elderly population due to increase in life expectancy, it also seem to be an age related increase in cancer incidence. Nevertheless, extending healthy life span could depend on how good cells achieve, during the prenatal period and few years after birth, the equilibrium between telomere length and telomerase activity, as seen in germ cells. After all, I suggest that decrease in mean telomere length might result in, on the one hand, an increased life span and, on the other, a higher risk of tumorigenesis.

Aged↗
PubMed2000

Structure-expression relationships of the 15-kDa selenoprotein gene. Possible role of the protein in cancer etiology.

Selenium has been implicated in cancer prevention, but the mechanism and possible involvement of selenoproteins in this process are not understood. To elucidate whether the 15-kDa selenoprotein may play a role in cancer etiology, the complete sequence of the human 15-kDa protein gene was determined, and various characteristics associated with expression of the protein were examined in normal and malignant cells and tissues. The 51-kilobase pair gene for the 15-kDa selenoprotein consisted of five exons and four introns and was localized on chromosome 1p31, a genetic locus commonly mutated or deleted in human cancers. Two stem-loop structures resembling selenocysteine insertion sequence elements were identified in the 3'-untranslated region of the gene, and only one of these was functional. Two alleles in the human 15-kDa protein gene were identified that differed by two single nucleotide polymorphic sites that occurred within the selenocysteine insertion sequence-like structures. These 3'-untranslated region polymorphisms resulted in changes in selenocysteine incorporation into protein and responded differently to selenium supplementation. Human and mouse 15-kDa selenoprotein genes manifested the highest level of expression in prostate, liver, kidney, testis, and brain, and the level of the selenoprotein was reduced substantially in a malignant prostate cell line and in hepatocarcinoma. The expression pattern of the 15-kDa protein in normal and malignant tissues, the occurrence of polymorphisms associated with protein expression, the role of selenium in differential regulation of polymorphisms, and the chromosomal location of the gene may be relevant to a role of this protein in cancer.

3' Untranslated Regions↗
PubMed2003

Lymphocyte recovery in advanced ovarian cancer patients after high-dose chemotherapy and peripheral blood stem cell plus growth factor support: clinical implications.

PURPOSE: The purpose of this study was to investigate the clinical role of immunological recovery together with selected biological parameters on long-term survival in a series of ovarian cancer administered high-dose chemotherapy with peripheral blood stem cell and growth factor support. EXPERIMENTAL DESIGN: Thirty-eight patients with stages IIIB-IV epithelial ovarian cancer were studied. Lymphocyte immunophenotyping for the identification of CD3(+), CD4(+), CD8(+), and CD3(-)/CD16(+)CD56(+) natural killer T cells and CD19 B cells was performed. RESULTS: Twenty-three patients (60%) had a CD3(+) cell count <850 cells/ microl. Multivariate logistic regression showed that tumor grading (chi(2) = 6.6, P = 0.010) and type of growth factor (chi(2) = 4.1, P = 0.042) retained an independent role in predicting T-cell recovery above the value of 850 cells/ microl. The 3-year time to progression (TTP) rate was 86% (95% confidence intervals, 70, 102) in cases with high CD3(+) cell count with respect to a 3-year TTP of 23% (95% confidence intervals, 8, 38) in cases with low CD3(+) cell count (P = 0.0026). The absolute number of CD3(+) cells was shown to be inversely associated with risk of progression (chi(2) = 4.8; P = 0.028), as assessed by Cox univariate analysis using CD3(+) cell count as continuous covariate. In multivariate analysis only residual tumor and status of CD3(+) cell counts retained an independent association with shorter TTP. Similar results were obtained for overall survival. CONCLUSIONS: Long-term immune reconstitution and particularly the recovery of adequate counts of CD3(+), CD4(+), and CD8(+) T cells are independent markers of longer TTP and overall survival in ovarian cancer patients receiving high-dose chemotherapy with peripheral blood stem cell and growth factor support.

CD3 Complex↗
PubMed1998

The antiemetic efficacy of granisetron plus dexamethasone, haloperidol and loracepam in breast cancer patients treated with high-dose chemotherapy with peripheral blood stem-cell support.

There has recently been a marked trend to increasing dose intensity in cancer chemotherapy, with or without peripheral blood stem-cell support, which has been associated with a higher frequency of nausea and vomiting. Antiemetic treatment in this setting has not been extensively analysed. From October 1995 to January 1997, prevention of emesis with granisetron 3 mg/12 h i.v., dexamethasone 12 mg/24 h i.v., haloperidol 0.5 mg/12 h p.o., and loracepam I mg/24 h p.o. was instituted in 30 breast cancer patients treated with high-dose chemotherapy (a 4-day intravenous continuous infusion of cyclophosphamide 1500 mg/m2 per day, thio-TEPA 125 mg/m2 per day and carboplatin 200 mg/m2 per day).A total of 30% of the patients (9/30) obtained complete or major protection on the 4 days of chemotherapy treatment (96.7% (29/30) on day 1, 86.7% (26/30) on day 2, 70% (21/30) on day 3, and 50% (15/30) on day 4). On the days following chemotherapy, 46.7% (14/30) presented fewer than two emetic episodes on day 5, 70% (21/30) on day 6, 83.4% (25/30) on day 7 and, 93.3% (28/30) on day 8. This energic antiemetic combination treatment has hardly any effect in the prevention of emesis, providing complete or major protection of 30% for the 4 days of chemotherapy treatment. Further investigation aimed at improving antiemetic treatment results is necessary.

Adult↗
PubMed1999

Pulmonary infiltrates after cytokine therapy for stem cell transplantation. Massive deposition of eosinophil major basic protein detected by immunohistochemistry.

Interleukin-2 (IL-2), a product of activated T-cells, is now being used in a number of protocols for cancer immunotherapy. In one stem cell transplantation protocol for breast cancer, IL-2 is used together with interferon-gamma (IFN-gamma) and cyclosporine to stimulate a graft-versus-tumor response and improve the likelihood of a prolonged remission. We present the case of a patient who developed peripheral eosinophilia, perihilar infiltrates, and hypoxemia after autologous stem cell transplantation and the use of recombinant IL-2 and IFN-gamma. Histologic analysis of transbronchial lung biopsies demonstrated a few eosinophils within the bronchial submucosa. Immunostaining using antibodies directed against eosinophil major basic protein (MBP), however, revealed massive extracellular deposition of this toxic granule protein throughout the lung parenchyma. IL-2 therapy is well known to induce a peripheral eosinophilia and to be associated with the capillary leak syndrome characterized by weight gain, edema, and oliguria. The findings noted in this case report suggest that the eosinophil activation that accompanies immunologic therapy with IL-2 can result in direct toxicity to the lung and a localized vascular leak syndrome. This syndrome should be considered in the differential diagnosis of pulmonary infiltrates that occur acutely after bone marrow transplantation with cytokine augmentation.

Blood Proteins↗
PubMed2004

A novel tumor cell line cloned from mutated human embryonic bone marrow mesenchymal stem cells.

A novel tumor cell line, denominated F6, was established from mutated human embryonic bone marrow mesenchymal stem cells (MSCs) which were induced by the GM-CSF and IL-4 in vitro. The characteristics of the F6 cell line, such as surface antigens, cell cycle, growth curve, gene expression, morphology, cytogenetics and tumor model were analyzed. The F6 cells were round and grew suspended in a plastic dish. The cell line has a strong self-renewal capability, was positive for CD13, CD29, CD44, but negative for CD1alpha, CD3, CD10, CD14, CD23, CD33, CD34, CD38, CD41, CD45, CD54 and HLA-DR. The surface antigens were lower than those of human embryonic MSCs. The karyotype of F6 cells was abnormal. The cell cycle included: G0/G1 phase, 52.24%; G2/M phase, 8.00%; S phase, 41.76%. After the cells had been passaged serially for more than 17 months (62 passages), their characteristics were still retained. The F6 cells resulted in tumors in SCID nude mice in vivo (8/8) and caused metastasis (3/8). The pathologic examination revealed that the tumor cells extensively invaded surrounding normal tissues such as dermis, muscular tissue, nerve tissue, adipose tissue and lymphoid tissue. F6 cell line, tumor tissues derived from F6 cells and the MSCs expressed different levels of the nucleostemin gene. These findings suggested that F6 may be a novel tumor cell line. It may provide evidence for the theory that cancer originates from stem cells, and may be useful for the investigation on safety of human MSCs in the clinical application.

Animals↗
PubMed1999

Evidence for ovarian granulosa stem cells: telomerase activity and localization of the telomerase ribonucleic acid component in bovine ovarian follicles.

We have previously postulated that granulosa cells of developing follicles arise from a population of stem cells. Stem cells and cancer cells can divide indefinitely partly because they express telomerase. Telomerase is a ribonucleoprotein enzyme that repairs the ends of telomeres that otherwise shorten progressively upon each successive cell division. In this study we carried out cell cycle analyses and examined telomerase expression to examine our hypothesis. Preantral (60-100 microm) and small (1 mm) follicles, as well as granulosa cells from medium-sized (3 mm) and large (6-8 mm) follicles, were isolated. Cell cycle analyses and expression of Ki-67, a cell cycle-related protein, were undertaken on follicles of each size (n = 3) by flow cytometry; 12% to 16% of granulosa cells in all follicles were in the S phase, and less than 2% were in the G(2)/M phase. Telomerase activity (n = 3) was highest in the small preantral follicles, declining at the 1-mm stage and even further at the 3-mm stage. In situ hybridization histochemistry was carried out on bovine ovaries, and telomerase RNA was detected in the granulosa cells of growing follicles but not primordial follicles. Two major patterns of staining were observed in the membrana granulosa of antral follicles: staining in the middle and antral layers, and staining in the middle and basal layers. No staining was detected in oocytes. Our results strongly support our hypothesis that granulosa cells arise from a population of stem cells.

Animals↗
PubMed2004

Effect of plasma exchange on plasma ADAMTS13 metalloprotease activity, inhibitor level, and clinical outcome in patients with idiopathic and nonidiopathic thrombotic thrombocytopenic purpura.

Therapeutic plasma exchange is an effective empiric treatment for thrombotic thrombocytopenic purpura (TTP), but how therapy affects the level of a disintegrin and metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13) or inhibitor has not been reported in many patients. We prospectively analyzed ADAMTS13 activity and inhibitor levels in 37 adults with TTP. ADAMTS13 level at presentation was lower than 5% in 16 of 20 patients with idiopathic TTP and in none of 17 patients with TTP associated with hematopoietic stem cell transplantation, cancer, drugs, or pregnancy (P <.00001). Seven of the 16 patients with ADAMTS13 activity lower than 5% ( approximately 44%) had inhibitors. For 8 patients followed serially with ADAMTS13 activity lower than 5% but no inhibitor at presentation, plasma exchange led to complete clinical remission and a rise in ADAMTS13 level. In contrast, 4 patients with low ADAMTS13 activity but high-titer inhibitor (> 5 units/mL) had neither a rise in ADAMTS13 activity nor a reduction in the inhibitor titer: 3 had recurrent disease and 1 died. Among 17 patients with AD-AMTS13 activity at presentation higher than 25%, 10 died. Mortality rate for idiopathic TTP was 15%, whereas mortality for nonidiopathic TTP was 59% (P <.02). We conclude that assays of ADAMTS13 activity and inhibitors in addition to the clinical categories (idiopathic TTP and nonidiopathic TTP) are predictive of outcome and may be useful to tailor patient treatment.

ADAM Proteins↗
PubMed2001

Use of capecitabine as first-line therapy in patients with metastatic breast cancer relapsing after high-dose chemotherapy and autologous stem cell support.

High-dose chemotherapy with autologous stem cell support (HDC-ASCS) can produce high complete remission rates in patients with metastatic breast cancer (MBC). However, the majority of those so treated will relapse within 3 years. The ability of such patients to tolerate further myelosuppressive chemotherapy may be limited and the best therapy is undefined. In this retrospective study we assessed the role of capecitabine as initial therapy after relapse. Ten patients (median age = 47 years; oestrogen receptor-positive, n = 4; visceral disease, n = 6; prior anthracycline, n = 8, prior taxanes, n = 10), whose disease progressed at a median of 246 days (range 69-480) after HDC-ASCS and who were treated with capecitabine (2500 mg/m2 per day for 2 weeks of a 3-week cycle) as initial therapy for relapse, were assessed retrospectively for response and toxicity. They received a median of eight cycles (range 4-24) of capecitabine. The toxicities encountered while receiving capecitabine were: hand-foot syndrome (grade 1, n = 3; grade 2, n = 4; grade 3, n = 1); diarrhoea (grade 1, n = 1; grade 2, n = 3); nausea (n = 2) and fatigue (n = 5). Haematological toxicity was seen in only one patient. No patient required hospitalization for toxicity. Three achieved a complete remission, four a partial remission and three disease stabilization. After a median follow-up of 183 days from commencing capecitabine (range 97-540), all patients were alive and five were in remission. Five progressed after remissions that lasted between 63 and 252 days. Oral capecitabine is an active and well-tolerated agent when used alone as first-line therapy in patients who have relapsed after HDC-ASCS for MBC.

Adult↗
PubMed2003

Predicting outcome based on Swenerton score in patients with metastatic breast cancer undergoing high-dose chemotherapy and autologous hematopoietic stem cell transplantation: implications for patient selection.

The aim of this study was to study the effectiveness of the Swenerton score in assessing extent of disease as an independent prognostic and predictive factor in patients with metastatic breast cancer (MBC) who receive high-dose chemotherapy (HDCT) with autologous hematopoietic stem cell transplant (AHSCT). Two-hundred thirty-two patients with MBC underwent HDCT. Extent of disease was assessed quantitatively using the Swenerton score. A retrospective analysis was performed using Cox proportional hazards regression and logistic regression models. One hundred three (44%) patients had a complete response (CR) after HDCT. Bone marrow as source of hematopoietic stem cells, hormone-receptor-negative status, and visceral involvement correlated with both worse overall survival (OS) and progression-free survival (PFS). Short disease-free interval, multiple sites of metastatic disease, and less than 50% reduction in the Swenerton Score during induction chemotherapy correlated with worse OS. Patients in CR at the time of HDCT had better PFS than patients in partial response, stable disease, or progressive disease. Fifty-six patients who underwent conversion to CR after HDCT had a similar median OS (not reached v 74 months; P =.51) and PFS duration (22 v 44 months; P =.15) as patients who received HDCT after a CR to standard-dose chemotherapy (SDCT). Conversion to CR was predicted by a >/=50% reduction in the Swenerton score during SDCT (odds ratio [OR] 3.32, P <.01) and soft-tissue disease (OR 4.08, P <.01). The presence of multiple metastatic sites predicted decreased probability of conversion to CR (OR 0.34, P <.01). The Swenerton score provides a thorough estimate of disease extent, and reduction of Swenerton score by SDCT is potentially useful for selecting the optimal candidates for HDCT trials who may achieve long-term disease control.

Adult↗
PubMed2005

Breast cancer resistance protein-mediated efflux of androgen in putative benign and malignant prostate stem cells.

Malignantly transformed stem cells represent a potential common nidus for the primary cancer and the recurrent cancer that arises after treatment failure. Putative prostate stem cells and prostate tumor stem cells in benign and malignant human prostate tissue, in primary human prostate xenografts, and in the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse model of prostate cancer, are defined by expression of breast cancer resistance protein (BCRP), a marker of pluripotent hematopoietic, muscle, and neural stem cells, and by an absence of androgen receptor (AR) protein. Inhibition of BCRP-mediated efflux of dihydrotestosterone by novobiocin or fumitremorgin C in a rat prostate progenitor cell line that expresses BCRP and AR mRNAs, but minimal AR protein, results in stabilization and nuclear translocation of AR protein, providing a mechanism for lack of AR protein in BCRP-expressing stem cells. In both benign and malignant human prostate tissue, the rare epithelial cells that express BCRP and lack AR protein are localized in the basal cell compartment, survive androgen deprivation, and maintain proliferative potential in the hypoxic, androgen-deprived prostate. Putative prostate tumor stem cells that express BCRP but not AR protein in TRAMP are the source of a BCRP-negative and AR-negative, Foxa2- and SV40Tag-expressing, transit amplifying compartment that progresses to the poorly differentiated carcinomas that arise rapidly after castration. Therefore, BCRP expression isolates prostate stem/tumor stem cells from the prostate tissue microenvironment through constitutive efflux of androgen, protecting the putative tumor stem cells from androgen deprivation, hypoxia, or adjuvant chemotherapy, and providing the nidus for recurrent prostate cancer.

ATP Binding Cassette Transporter, Subfamily G, Mem↗
PubMed2005

The role of human adult stem cells and cell-cell communication in cancer chemoprevention and chemotherapy strategies.

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 underlying mechanism(s) of each phase, In principle, prevention of each of these phases could reduce the risk to cancer. However, because reducing the mutagenic/initiation phase to a zero level is impossible, the most efficacious intervention would be at the promotion phase that requires a sustained exposure to promoting conditions/agents. In addition, 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 kinds of agents. A hypothesis will be proposed that involves adult stem cells, which express Oct-4 gene and lack gap junctional intercellular communication (GJIC-) or the early progenitor 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. Consequently, anti-tumor promoting chemopreventing agents to each of these two types of initiated cells must have different mechanisms of action and work on different target cells. Assuming stem cells are target cells for carcinogenesis, an alternative method of chemoprevention would be to reduce the stem cell pool. Many classes of anti-tumor promoter chemopreventive agents, such as green tea components, resveratrol, caffeic acid phenethylene ester, either up-regulate GJIC in stem cells or prevent the down regulation of GJIC by tumor promoters in early progenitor cells.

Adult↗
PubMedDate not supplied

The psychosocial experience of women treated for breast cancer by high-dose chemotherapy supported by autologous stem cell transplant: a qualitative analysis of support groups.

Autologous bone marrow transplantation (AuBMT) is probably among the most aggressive of physical treatments endured by cancer patients. High-risk breast cancer patients who choose this therapy face prolonged, agonizing and life-threatening interventions that are no less arduous than confronting the malignant disease itself. The study, which aimed to broadening our understanding of the psychosocial impact and the implications of AuBMT, presents a protocol analysis of group support intervention in 45 recipients (eight to ten women in five groups). The sessions were held at the Transplant Department at the Chaim Sheba Medical Center. The contribution of group support to the healing process was examined. The findings show that recovery was affected by a wide range of psychosocial factors, specifically highlighting the impact of transplantation and survival on five domains, viz. physical, psychological/emotional, vocational, social and family/spousal intimacy. Illness and treatment management is also discussed. The support generated by the group, both individually and collectively, was found to contribute significantly to the spectrum of resources available to the participants.

Adaptation, Psychological↗
PubMed2003

Interleukin-6 -174G-->C polymorphism is associated with improved outcome in high-risk breast cancer.

Axillary lymph node involvement in breast cancer is a marker of recurrence risk. Despite aggressive adjuvant therapy, recurrence in patients with four or more involved lymph nodes approaches 50% at 5 years from diagnosis. Markers that can distinguish those likely to relapse from those likely to be cured are needed to tailor therapy and provide accurate prognostic information to patients. Although most work in this area has focused on tumor characteristics, we hypothesized that the host environment might also play a role in determining risk of relapse. We hypothesized that host inflammatory response, mediated in part by production of interleukin-6 (IL-6), might play a role in the elimination of microscopic residual tumor. Polymorphisms in the IL-6 promoter region appear to modulate serum levels of the cytokine via regulation of gene transcription. A single nucleotide polymorphism involving substitution of cytosine for guanine at position -174 has been associated with reduced transcription and improved outcome in a variety of nonmalignant diseases, including coronary artery disease and several autoimmune conditions. Tumor necrosis factor (TNF) alpha is a proinflammatory cytokine that also plays a role in regulating IL-6 transcription. We hypothesized that polymorphisms in IL-6 (-174 G>C) or TNF-alpha (G-238 or G-308) might be associated with prognosis in a subset of patients with high-risk breast cancer. Genotyping was performed on DNA from stored stem cells in 80 breast cancer patients diagnosed with at least four positive axillary lymph nodes at diagnosis who underwent anthracycline-based adjuvant chemotherapy followed by high-dose multiagent chemotherapy with stem cell rescue. Cox proportional hazards models were used to estimate the effect of genotype and other known prognostic factors on disease-free and overall survival (DFS and OS, respectively). The presence of at least one C allele in the IL-6 promoter at position -174 was significantly associated with both DFS and OS compared with G/G homozygotes. After adjustment for estrogen receptor (ER) status, number of involved lymph nodes, and tumor size, those patients carrying the G/G genotype had a 2.1-fold increase in the rate of failure and a 2.6-fold increase in the rate of death compared with carriers of any C allele at a mean follow-up of 55 months. ER status modulated the effect of IL-6 polymorphism: both DFS and OS were most favorable in patients who were carriers of any C-allele (G/C or C/C) and had ER-positive tumors. The presence of either G/G genotype or an ER-negative tumor increased the hazard of failure [hazard ratio (HR), 2.6 and 3.2, respectively] and death (HR, 2.0 and 2.2, respectively). The combination of both G/G genotype and ER-negative tumor resulted in an additional increase in the hazard of failure (HR, 5.4; four-group comparison, P = 0.003) and death (HR, 6.2; four-group comparison, P = 0.001). TNF-alpha -308 and -238 polymorphisms were not associated with variation in DFS or OS in this cohort. The IL-6-174 promoter polymorphism is associated with clinical outcome in this cohort of node-positive breast cancer patients who received high-dose adjuvant therapy. IL-6 genotype modulated the effect of ER status on outcome. These results support the hypothesis that IL-6 may play an important role in the control of micrometastatic disease in breast cancer. Additional studies are needed to confirm these results and elucidate the mechanisms responsible for these differences.

Adult↗