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P Soubeyran

Publications and source records attributed to P Soubeyran.

At least 19 recordsLinked to original sources

EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer: 2006 update.

Anaemia is frequently diagnosed in patients with cancer, and may have a detrimental effect on quality of life (QoL). We previously conducted a systematic literature review (1996-2003) to produce evidence-based guidelines on the use of erythropoietic proteins in anaemic patients with cancer.[Bokemeyer C, Aapro MS, Courdi A, et al. EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer. Eur J Cancer 2004;40:2201-2216.] We report here an update to these guidelines, including literature published through to November 2005. The results of this updated systematic literature review have enabled us to refine our guidelines based on the full body of data currently available. Level I evidence exists for a positive impact of erythropoietic proteins on haemoglobin (Hb) levels when administered to patients with chemotherapy-induced anaemia or anaemia of chronic disease, when used to prevent cancer anaemia, and in patients undergoing cancer surgery. The addition of further Level I studies confirms our recommendation that in cancer patients receiving chemotherapy and/or radiotherapy, treatment with erythropoietic proteins should be initiated at a Hb level of 9-11 g/dL based on anaemia-related symptoms rather than a fixed Hb concentration. Early intervention with erythropoietic proteins may be considered in asymptomatic anaemic patients with Hb levels 11.9 g/dL provided that individual factors like intensity and expected duration of chemotherapy are considered. Patients whose Hb level is below 9 g/dL should primarily be evaluated for need of transfusions potentially followed by the application of erythropoietic proteins. We do not recommend the prophylactic use of erythropoietic proteins to prevent anaemia in patients undergoing chemotherapy or radiotherapy who have normal Hb levels at the start of treatment, as the literature has not shown a benefit with this approach. The addition of further supporting studies confirms our recommendation that the target Hb concentration following treatment with erythropoietic proteins should be 12-13 g/dL. Once this level is achieved, maintenance doses should be titrated individually. There is Level I evidence that dosing of erythropoietic proteins less frequently than three times per week is efficacious when used to treat chemotherapy-induced anaemia or prevent cancer anaemia, with studies supporting the use of epoetin alfa and epoetin beta weekly and darbepoetin alfa given every week or every 3 weeks. We do not recommend the use of higher than standard initial doses of erythropoietic proteins with the aim of producing higher haematological responses, due to the limited body of evidence available. There is Level I evidence that, within reasonable limits of body weight, fixed doses of erythropoietic proteins can be used to treat patients with chemotherapy-induced anaemia. This analysis confirms that there are no baseline predictive factors of response to erythropoietic proteins that can be routinely used in clinical practice if functional iron deficiency or vitamin deficiency is ruled out; a low serum erythropoietin (EPO) level (only in haematological malignancies) appears to be the only predictive factor to be verified in Level I studies. Further studies are needed to investigate the value of hepcidin, c-reactive protein, and other measures as predictive factors. In these updated guidelines, we explored a new question of whether oral or intravenous iron supplementation increases the response rate to erythropoietic proteins. We found no evidence of increased response with the addition of oral iron supplementation, but there is Level II evidence of improved response to erythropoietic proteins with the addition of intravenous iron. However, the doses and schedules for intravenous iron supplementation are not yet well defined, and further studies in this area are warranted. The two major goals of erythropoietic protein therapy are prevention or elimination of transfusions and improvement of QoL. The total body of evidence shows that red blood cell (RBC) transfusion requirements are reduced following treatment with erythropoietic proteins. This analysis also confirms that QoL is significantly improved in patients with chemotherapy-induced anaemia and in those with anaemia of chronic disease following erythropoietic protein therapy, with more robust evidence now available that QoL was improved in studies investigating early intervention in cases of chemotherapy- or radiotherapy-induced anaemia. There is only indirect evidence that patients with chemotherapy-induced anaemia or anaemia of chronic disease initially classified as non-responders to standard doses proceed to respond to treatment following a dose increase. None of the studies addressed the question in a prospective, randomised fashion, and so the Taskforce does not recommend dose escalation as a general approach in all patients who are not responding. There is still insufficient data to determine the effect on survival following treatment with erythropoietic proteins in conjunction with chemotherapy or radiotherapy. Our analysis of survival endpoints in studies involving patients receiving radio(chemo)therapy found that most studies were inconclusive, with no clear link between the use of erythropoietic proteins and survival. Likewise, we found no clear link between erythropoietic therapy and other endpoints such as local tumour control, time to progression, and progression-free survival. There is no evidence that pure red cell aplasia occurs in cancer patients following treatment with erythropoietic proteins, and the fear of this condition developing should not lead to erythropoietic proteins being withheld in patients with cancer. There is Level I evidence that the risk of thromboembolic events and hypertension are slightly elevated in patients with chemotherapy-induced anaemia receiving erythropoietic proteins. Additional trials are warranted, especially to define the optimal doses and schedules of intravenous iron supplementation during erythropoietic therapy. While our review did not address cost benefit evaluations in detail, the consensus is that studies taking into account all real determinants of cost and benefit need to be performed prospectively.

Anemia↗

EORTC guidelines for the use of erythropoietic proteins in anaemic patients with cancer.

Anaemia is frequently diagnosed in patients with cancer, yet it is difficult to identify a single cause due to its multifactorial aetiology. We conducted a systematic literature review (1996-2003) to produce evidence-based guidelines on the use of erythropoietic proteins in anaemic patients with cancer (see ). Level I evidence exists for a positive impact of erythropoietic proteins on haemoglobin (Hb) levels when administered to patients with chemotherapy-induced anaemia or anaemia of chronic disease, when used to prevent cancer anaemia, in patients undergoing cancer surgery and following allogeneic bone marrow transplantation. The Hb level at which erythropoietic protein therapy should be initiated is difficult to determine as it varied between studies; a large number of Level I studies in patients with chemotherapy-induced anaemia or anaemia of chronic disease enrolled patients with a Hb concentration </=105 g/L, but none compared the effect of different baseline Hb levels on the response to treatment. Similarly, several studies defined the target Hb concentration as 120-130 g/L following treatment with erythropoietic proteins, but none specifically addressed the correlation between target Hb level and clinical benefit in a randomised fashion. Level I evidence shows that red blood cell (RBC) transfusion requirements are significantly reduced with erythropoietic protein therapy in patients with chemotherapy-induced anaemia or when used to prevent cancer anaemia (approximately 20% reduction compared with controls). We found indirect Level I and III evidence that patients with chemotherapy-induced anaemia or anaemia of chronic disease initially classified as non-responders to standard doses proceed to respond to treatment following a dose increase (absolute increases in response rate ranged from 8% to 18%). However, none of these studies examined the effect on response rates of a longer treatment period at the lower dose, or performed a randomised comparison of a dose increase versus an unchanged dose. There is Level I evidence to show that quality-of-life (QOL) is significantly improved in patients with chemotherapy-induced anaemia and in those with anaemia of chronic disease, particularly in patients achieving a Hb response to erythropoietic protein therapy. There are insufficient data to determine the effect on survival following treatment with erythropoietic proteins in conjunction with chemotherapy or radiotherapy. There is Level I evidence that dosing of erythropoietic proteins less frequently than three times per week (TIW) is efficacious when used to treat chemotherapy-induced anaemia or prevent cancer anaemia. There is Level III evidence that initial doses of erythropoietic proteins considered to be higher than current standard practice produce higher haematological responses in patients with chemotherapy-induced anaemia or anaemia of chronic disease. Level I evidence demonstrates that several baseline patient parameters (e.g., low endogenous erythropoietin [EPO] concentration, age <60 years, Hb concentration >/=90 g/L) impact upon the response to erythropoietic proteins when used to treat chemotherapy-induced anaemia or prevent cancer anaemia. Evidence indicates that endogenous EPO concentration impacts on response in patients with lymphoproliferative malignancies, but is not a valid parameter in patients with solid tumours. There is Level I evidence that fixed doses of erythropoietic proteins can be used at the start of therapy to treat patients with chemotherapy-induced anaemia, but maintenance doses should be titrated individually. There is no evidence that pure red cell aplasia (PRCA) occurs following treatment with erythropoietic proteins in patients with chemotherapy-induced anaemia or when used prophylactically in patients with cancer. There is Level I evidence that the risk of thromboembolic events and hypertension are slightly elevated in patients with chemotherapy-induced anaemia receiving erythropoietic proteins. Level I evidence supports the effectiveness of erythropoietic proteins to prevenroteins to prevent anaemia in non-anaemic cancer patients receiving chemotherapy or radiotherapy or in those undergoing cancer surgery. However, these are non-licensed indications and we do not currently recommend the prophylactic use of erythropoietic proteins to prevent anaemia in patients who have normal Hb values at the start of treatment. Additional trials are warranted, especially on the issues of iron replacement and cost-effectiveness of erythropoietic protein therapy, as well as on tumour response/progression and survival.

Anemia↗

Chemotherapy alone as initial treatment for primary CNS lymphoma in patients older than 60 years: a multicenter phase II study (26952) of the European Organization for Research and Treatment of Cancer Brain Tumor Group.

PURPOSE: To assess the efficacy and toxicity of chemotherapy alone in patients older than 60 years with primary CNS lymphoma. PATIENTS AND METHODS: Fifty patients with a median age of 72 years and a median Karnofsky performance score (KPS) of 50 were eligible for this multicenter phase II study. The protocol consisted of high-dose methotrexate (MTX), lomustine, procarbazine, methylprednisolone, and intrathecal chemotherapy with MTX and cytarabine. The patients received one induction cycle; if objective response was achieved, five additional maintenance cycles were administered every 6 weeks. The median follow-up of patients was 3 years. RESULTS: Twenty four patients (48%) achieved an objective response (compete response [CR], 42%; partial response, 6%), with a median duration of CR of 27 months (range, 3 to 47+ months). Overall median survival time was 14.3 months, and 1-year progression-free survival was 40% (95% confidence interval [CI], 26% to 53%). Myelosuppression was the most frequent side effect, with grade 3 to 4 neutropenia in 19% of patients. One patient died during chemotherapy, as a result of pulmonary embolism. Most patients improved or preserved their cognitive functions (47% and 45% of the patients, respectively) and KPS (36% and 52% of the patients, respectively) until relapse, whereas cognitive and KPS decline attributed to delayed treatment neurotoxicity occurred in 8% and 12% patients, respectively. CONCLUSION: In the elderly, this chemotherapy regimen compares favorably with radiotherapy (RT) alone and reduces considerably the risk of delayed neurotoxicity associated with combined chemoradiotherapy. Chemotherapy alone is an appropriate strategy in older patients to delay or avoid RT.

Age Factors↗

Cbl signaling networks in the regulation of cell function.

Cbl proteins control multiple cellular processes by acting as ubiquitin ligases and multifunctional adaptor molecules. They are involved in the control of cell proliferation, differentiation and cell morphology, as well as in pathologies such as autoimmune diseases, inflammation and cancer. Here we review recent advances in understanding the role of Cbl and the importance of a growing repertoire of Cbl-interacting proteins in the regulation of signaling pathways triggered by growth factors, antigens, cell adhesion, cytokines and hormones. We also address key issues of the nature of proteins that bind Cbl in particular cells, where they are located, and how they are altered or traffic within cells upon stimulation. It is becoming obvious that temporal and spatial changes in Cbl signaling networks are essential for the control of physiological processes in a variety of cells and organs and that their deregulation can result in the development of human diseases.

Animals↗

EORTC Cancer in the Elderly Task Force guidelines for the use of colony-stimulating factors in elderly patients with cancer.

Increasing age is not, in itself, a contraindication to cancer chemotherapy. Myelosuppression, however, a common adverse consequence of the administration of many standard-dose chemotherapy regimens to both young and elderly patients with cancer, increases with age. The risk of development of febrile neutropenia may contribute to a reluctance to administer chemotherapy in the elderly patient population. We conducted a detailed literature search (1992-2002) to derive evidence-based conclusions on the value of prophylactic colony-stimulating factor (CSF) administration in elderly patients receiving chemotherapy. Sufficient evidence allows us to affirm that prophylactic granulocyte colony-stimulating factor (G-CSF) reduces the incidence of chemotherapy-induced neutropenia, febrile neutropenia and infections in elderly patients receiving myelotoxic chemotherapy for non-Hodgkin's lymphoma (NHL), small-cell lung cancer (SCLC) or urothelial tumours. Lack of available trial data does not allow similar conclusions to be drawn for other cancers studied, but it is likely that similar benefits would accrue from the use of prophylactic G-CSF. There is insufficient evidence to extend this recommendation to include the use of granulocyte-macrophage colony-stimulating factor (GM-CSF). There are insufficient data available to allow the evaluation of the impact of prophylactic CSF on the incidence of toxic deaths in elderly patients with cancer and this is a crucial question for geriatric oncology practice. There is no evidence in elderly patients that the delivery of standard-dose chemotherapy on schedule improves efficacy measures. The data show that febrile neutropenic events are more likely to occur during the first and second cycles of chemotherapy, thus prophylactic measures should be considered early in the course of treatment. Furthermore, since systematic dose reduction can impact on outcome, primary prophylactic use of G-CSF for all elderly patients receiving curative myelotoxic chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) or CHOP-like) is indicated and we suggest a risk-adapted strategy with primary prophylactic G-CSF administration in high-risk patients. Dose intensification, through dose interval reduction, facilitated by prophylactic G-CSF, improved survival in elderly patients with some specific diseases. There is a need for further well-designed studies to identify the elderly patients who will benefit most from prophylactic G-CSF. To achieve this, we strongly urge the design of and participation in further trials.

Aged↗

Homeobox gene Cdx1 regulates Ras, Rho and PI3 kinase pathways leading to transformation and tumorigenesis of intestinal epithelial cells.

The Cdx1 homeobox gene encodes for an intestine-specific transcription factor involved in the control of proliferation and differentiation of epithelial cells. Although it has been indicated that Cdx1 may act as a proto-oncogene in cultured fibroblasts, its direct role in the regulation of intestinal tumorigenesis has not been demonstrated. Here we show that expression of Cdx1 in an intestinal epithelial cell line (IEC-6) induces anchorage-independent growth in soft agar and promotes the formation of adenocarcinoma in vivo. The phenotype of Cdx1-induced tumors was exacerbated when IEC-6/Cdx1 cells were injected together with matrigel containing mitogens and extracellular matrix components. These changes were correlated with an increase in the GTP-bound form of Ras, modulation of Cdc42 and Rho-A activities, and accumulation of phosphatidyl inositol 3 (PI3) kinase products. Moreover, combined inhibition of Ras/Rho and PI3 kinase signaling by synthethic inhibitors blocked colony formation of IEC-6/Cdx1 cells in soft agar. Taken together, these results demonstrate a direct involvement of Cdx1, and its collaboration with Ras, Rho and PI3 kinase pathways, in transformation and tumorigenesis of intestinal epithelial cells.

Animals↗

Rituximab (anti-CD20 monoclonal antibody) as single first-line therapy for patients with follicular lymphoma with a low tumor burden: clinical and molecular evaluation.

The clinical activity of rituximab, a chimeric monoclonal antibody which binds to the CD20 antigen, was evaluated as a single first-line therapy for patients with follicular non-Hodgkin lymphoma (NHL). Fifty patients with follicular CD20(+) NHL and a low tumor burden were analyzed for clinical and molecular responses. They received 4 weekly infusions of rituximab at a dose of 375 mg/m(2). The response rate a month after treatment (day 50) was 36 of 49 (73%), with 10 patients in complete remission, 3 patients in complete remission/unconfirmed, and 23 patients in partial remission. Ten patients had stable disease, and the disease progressed in 3 patients. One of 13 (8%) patients in complete remission, 9 of 23 (39%) patients in partial remission, and 5 of 10 (50%) patients with stable disease exhibited disease progression during the first year. Within the study population, 32 patients were initially informative for polymerase chain reaction (PCR) data on bcl-2-J(H) rearrangement. On day 50, 17 of 30 patients (57%) were negative for bcl-2-J(H) rearrangement in peripheral blood, and 9 of 29 (31%) were negative in bone marrow; a significant association was observed between molecular and clinical responses (P <.0001). At month 12, 16 of 26 patients (62%) were PCR negative in peripheral blood. These results indicate that early molecular responses can be sustained for up to 12 months and that this response is highly correlated with progression-free survival. Rituximab has a high clinical activity and a low toxicity and induces a high complete molecular response rate in patients with follicular lymphoma and a low tumor burden.

Adolescent↗

Cdx1 promotes cellular growth of epithelial intestinal cells through induction of the secretory protein PAP I.

Expression of the Cdx1 homeobox gene in epithelial intestinal cells promotes cellular growth and differentiation. Cdx1and the Pancreatitis Associated Protein I (PAP I) are concomitantly expressed in the epithelial cells of the lower part of the intestinal crypts. Because Cdx1 is a transcription factor and PAP I, in other tissues, is a proliferative factor, we looked for a relationship between these two proteins in the intestinal-derived IEC-6 cells. After stable transfection with a Cdx1 expression vector, they produce high levels of the PAP I transcript and protein indicating a functional link between the two genes. Demonstration of Cdx1 binding to the PAP I promoter region and suppression of PAP I induction after deletion of the corresponding sequence indicated that Cdx1 is a transcription factor controlling PAP I gene expression in intestinal cells. By infecting IEC-6 cells with adenoviruses expressing PAP I, we demonstrated that PAP I induces mitosis in these cells. On the other hand, inhibition of the PAP I expression in the IEC-6 Cdxl-expressing cells using an antisense strategy confirmed the requirement of this protein for the effect of Cdx1 on cell growth. Finally, addition of the immunopurified PAP I to the culture medium promotes cell growth of the IEC-6 cells in a dose-dependent manner. Maximal effect was obtained at 1 ng/ml. Taken together these results demonstrate that PAP I is a target of the Cdx1 homeobox gene in intestinal cells which participates in the regulation of intestinal cell growth via an autocrine and/or paracrine mechanism.

Acute-Phase Proteins↗

Expression of the stress-induced p8 mRNA is transiently activated after culture medium change.

We report here that the mere fact of changing culture medium for fresh medium induced in several cell lines the expression of stress-activated genes including protein kinases p38, JNK and ERK1/2 and the transcription factor C/EBPbeta. As a consequence, p8, a gene induced by stress in several tissues, was strongly up-regulated. Induction did not occur after change for cell-conditioned medium. Induction was however transient, with a peak at 60 min for p38, at 15-30 min for JNK and at 15 min for ERK1/2, at 2-3 hours for C/EBPbeta and at 4-6 hours for p8. Repression of the induction was due to the secretion of thermolabile molecule(s) that progressively conditioned the medium. As low as 25% of conditioned medium added to fresh culture medium was sufficient to abolish the stress response. Taken together, our data indicate that the renewal of culture medium induces a transient cellular stress that may be a source of artifacts in experiments performed shortly after a change of culture medium.

3T3 Cells↗

A 1-kb Bcl-2-PCR fragment detection in a patient with follicular lymphoma and development of a new diagnostic PCR method.

The t(14;18) translocation is a useful marker to characterize follicular lymphoma and to monitor residual disease. The polymerase chain reaction (PCR) is a powerful technique to detect this translocation. Located on chromosome 18, within the Bcl-2 gene, breakpoints occur mainly in the 3; untranslated region, in the third exon of Bcl-2 (MBR region). In this study, the authors amplified MBR breakpoints by PCR and found an unexpectedly large fragment of 1 Kb that corresponds to a recently described new breakpoint in the Bcl-2 gene. With a new primer set, a further previously considered t(14;18)-unrelated tumor was in fact positive for this new breakpoint.

Base Sequence↗

Overexpression of Cdx1 and Cdx2 homeogenes enhances expression of the HLA-I in HT-29 cells.

We have previously reported that down-regulation of Cdx1 and Cdx2 mRNA expression is associated with colon carcinogenesis, and that coordinated reexpression of these genes in the HT29 colon cancer-derived cell line leads to a reduced malignant phenotype. Here we show that restoring Cdx1 and Cdx2 expression in HT29 cells enhanced the antigen presentation system, as reflected by a strong induction of the concentration of HLA-I molecules at the cell surface, resulting from increased expression of the HLA-I mRNA. Expression of the LMP2 proteasomal protein was also strongly induced by Cdx1 and Cdx2 at the transcriptional level, whereas TAP1 expression which is under the control of the same bidirectional promoter as LMP2 remained unchanged. Furthermore, expression of the adhesion molecule ICAM-1, which works in concert with HLA-I, and of the cell death promoter Fas was also increased upon Cdx1 and Cdx2 expression. Taken together, these results suggest that loss of Cdx1 and Cdx2 expression during colorectal carcinogenesis could favor the escape of tumor cells from the immune system. In conclusion, restoration of Cdx1 and Cdx2 expression should be considered in immunotherapeutic strategies for colorectal cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Follicular lymphomas--a review of treatment modalities.

Follicular lymphoma is the most common low-grade non Hodgkin's lymphoma and represent an homogeneous entity as defined by pathological, molecular and clinical data. This indolent disease is characterised by a slow growth pattern with possible spontaneous regression, is often disseminated but remains incurable with available treatments when disseminated. For localised stages, involved field radiotherapy remains the standard choice but other approaches remain to be investigated. In advanced disease, chemotherapy has been demonstrated to produce high response rates but recent trials with new treatment strategies including interferon and monoclonal antibodies may improve the current situation. In this article, we will review treatment of follicular lymphomas, specially emphasising published phase III trials.

Humans↗

Current treatment of Hodgkin's disease.

In spite of the fact that Hodgkin's disease (HD) remains still an enigma its management and treatment yield a cure rate of about 80% of all patients. However, this management has two limits: on one side favourable cases which should not be overtreated because of unacceptable side-effects, and on the other side very unfavourable cases which should be treated differently because of a very high rate of failure and/or relapse. Then it becomes necessary to precise as thoroughly as possible these two limits in order to choose the adequate treatment for the patient. Prognostic factors based on patient and disease characteristics allow a relatively exact classification of favourable and unfavourable cases. This distinction in two prognostic groups has therapeutic implications in terms of chemotherapy (regimen, duration) and radiotherapy (extension, doses). Other specific situations have to be considered, e.g. pediatric cases, pregnancy, old age and HIV-infected patients who need an adapted management according to very different situations.

Antineoplastic Combined Chemotherapy Protocols↗

Semen analysis and cryoconservation before treatment in Hodgkin's disease.

BACKGROUND: The prophylaxis of the late effects of chemotherapy and radiotherapy has become one of the major concerns in the management of Hodgkin's disease (HD). Unlike other complications, male sterility could be managed by prior semen preservation (SP). PATIENTS AND METHODS: To evaluate the semen quality of patients with HD and the outcome of insemination, we reviewed spermograms of patients who underwent SP before any treatment. The following criteria were necessary: 1) age > 16 and < 50; 2) HD of any stage; 3) informed about male sterility after HD treatment; 4) fully consenting. RESULTS: Such a proposal was made to 316 men, and 94 fulfilled the criteria. All patients underwent an initial chemotherapy. Mean age of the cohort was 27.5 years (range 16-48 years). Pretherapeutic staging of HD revealed 38 stage I (40%), 38 II (38%), 14 III (15%) and 4 IV (4%). Semen analysis before cryoconservation showed an overall 53% of normal or subnormal cases (50 cases). The analysis of semen quality and spermatozoid amount according to various parameters failed to find a correlation with stage, B symptoms, age, or biologic data (LDH, WBC, platelets, ESR). The use of cryopreserved semen was requested by 13 patients; 88 inseminations were performed leading to 9 pregnancies and 2 births. CONCLUSIONS: The low rate of success with cryopreserved semen in these cases suggests the need for a more careful design of non-toxic chemotherapy regimens in combined modality treatment.

Adolescent↗

Competitive polymerase chain reaction to quantify tumor cells in peripheral blood of patients with T(14;18)-bearing follicular non-Hodgkin's lymphoma: an exploratory study in 8 patients.

Detection of residual disease in follicular lymphoma is hampered by the observation of t(14;18)-bearing cells in the blood of healthy adult humans. To overcome this problem, we decided to validate a quantification method of t(14;18)-bearing cells and test it in t(14;18)-bearing follicular lymphomas (FL). We designed a competitive PCR method to quantify t(14;18)-bearing cells in peripheral blood. First, we controlled overall reliability (specificity, sensitivity, reproducibility, precision and accuracy); then we used our method to study 16 peripheral blood samples collected in 8 patients with t(14;18)-bearing FL. There were considerable variations in the number of circulating tumor cell (CTC) in FL patients, ranging from zero to 17,813 cells/ml. In 2 patients who were sampled before and after treatment and who attained complete remission (CR), a significant decrease in the number of CTC was observed. In 3 patients with detectable CTC during CR, relapse occurred 4 to 11 months later. Of 3 patients with no detectable CTC, 2 remain in CR 35 and 95 months later, but one relapsed 11 months after sample collection. These preliminary results suggest that quantification of CTC may be worthwhile in follicular lymphoma. It may improve our ability to predict relapse occurrence, but also may help in understanding this peculiar disease. Int. J. Cancer (Pred. Oncol.) 84:558-561, 1999.

Chromosomes, Human, Pair 14↗

pap, reg Ialpha and reg Ibeta mRNAs are concomitantly up-regulated during human colorectal carcinogenesis.

We have established the phenotype of a colorectal tumor by partial sequencing of 2166 transcripts that were eventually arrayed on high-density filters. These filters were used for differential screening with mRNAs of colorectal cancer and normal adjacent mucosa to characterize genes whose expression is altered in colorectal carcinoma. Three genes encoding related proteins, PAP, reg Ialpha and reg Ibeta, were over-expressed in cancer. Northern-blot analysis confirmed that their expression was very low in normal colonic epithelial cells, but elevated in 75% of tumors. Western blotting with specific antibodies to pap and reg Ialpha revealed in tumors a single band of the expected size ( 15-16 kDa), demonstrating synthesis of the proteins. Pap was localized by immunohistochemistry to the cytoplasm of epithelial cells. In cancerous tissue, many cells showed a strong staining signal, but the proportion of stained cells was variable among patients. In normal mucosa, staining was light and restricted to a few cells scattered in the epithelium. Similar results were obtained with antibodies against reg Ialpha. No significant relationship was found between concentrations of pap, reg Ialpha or reg Ibeta and clinical outcome. We looked at potential effectors of pap/reg gene over-expression by testing, in 2 adenocarcinoma cell lines, the efficacy of the pap promoter at driving a reporter gene; strong induction was observed upon exposure to IFNgamma and IL-6. By analogy with observations in hepatocellular carcinoma, our results suggest that prevention of PAP/reg expression in normal colon cells by silencing their gene promoters is relieved during colon carcinogenesis, allowing their up-regulation by mediators such as cytokines.

Biomarkers, Tumor↗

Cdx1 promotes differentiation in a rat intestinal epithelial cell line.

BACKGROUND & AIMS: Homeobox genes are involved in establishing and maintaining differentiated patterns in adult tissues. Cdx1 might carry out that function in the intestinal epithelium because its expression is specific to that tissue and increases during development. METHODS: Cdx1 expression was induced in IEC-6 intestinal epithelial cells by stable transfection, and subsequent changes in cell growth, resistance to apoptosis, migration, and differentiation were monitored. RESULTS: Compared with control, IEC-6/Cdx1 cells proliferated more rapidly, were more resistant to apoptosis, and migrated 3-4 times faster, as shown by an in vitro wound assay. IEC-6/Cdx1 cells in culture formed multilayers. Morphology of the top layer was similar to that of columnar epithelium, with cells showing typical features of differentiated enterocytes, including complex junctions and well-developed microvilli with glycocalix. Expression of 2 markers of enterocyte differentiation, aminopeptidase N and villin, was induced in IEC-6/Cdx1 cells. Aminopeptidase N was targeted to the basolateral membrane, and villin was localized to the cytoplasm. Actin filaments, which were mostly present in transcytoplasmic stress fibers in control cells, were redistributed to the cortex in Cdx1-transfected cells. CONCLUSIONS: Cdx1 expression in IEC-6 cells induces phenotypic changes characteristic of differentiating enterocytes, suggesting an important role for Cdx1 in the transition from stem cells to proliferating/transit cells.

Actins↗