Differential effect of adjuvant taxane-based and taxane-free chemotherapy regimens on the CK-19 mRNA-positive circulating tumour cells in patients with early breast cancer.

BACKGROUND: To determine the effect of adjuvant taxane-free and taxane-based chemotherapy regimens on the elimination of circulating tumour cells (CTCs) in patients with early breast cancer. METHODS: The presence of CK-19 mRNA-positive CTCs in the peripheral blood was evaluated before and after chemotherapy, using a real-time RT-PCR assay, in a historical comparison of two cohorts of women with stage I-III breast cancer treated with adjuvant taxane-free (N=211; FE(75)C or E(75)C) and taxane-based (N=334; T/E(75)C or T/E(75)) chemotherapy. RESULTS: Taxane-based chemotherapy resulted in a higher incidence of CTCs' elimination than taxane-free regimens since 49.7% (74 of 149) and 33.0% (29 of 88) of patients with detectable CTCs before chemotherapy, respectively, turned negative post-chemotherapy (P=0.015). Patients treated with taxane-free regimens had a significantly lower disease-free survival (DFS) (P=0.035) than patients treated with taxane-based regimens; this difference was observed in patients with but not without detectable CTCs before chemotherapy (P=0.018 and P=0.481, respectively). The incidence of deaths was significantly higher in the taxane-free cohort of patients with but not without detectable CTCs before chemotherapy compared with that of the taxane-based cohort (P=0.002). Multivariate analysis revealed that the chemotherapy regimen was significantly associated with prolonged DFS (HR: 2.00; 95% CI=1.20-3.34). CONCLUSION: Elimination of CK-19 mRNA-positive CTCs during adjuvant chemotherapy seems to be an efficacy indicator of treatment and is associated with a favourable clinical outcome of patients with detectable CTCs before chemotherapy.

Clinical relevance of circulating CK-19mRNA-positive tumour cells before front-line treatment in patients with metastatic breast cancer.

BACKGROUND: To investigate the clinical relevance of CK-19mRNA-positive circulating tumour cells (CTCs) detected before the initiation of front-line treatment in patients with metastatic breast cancer (MBC). METHODS: The presence of CTCs was detected in 298 patients with MBC using a real-time PCR (RT-PCR assay. In 44 patients, the detection of CTCs was evaluated by both the CellSearch and the RT-PCR assay. Interaction with known prognostic factors and association of CTCs with clinical outcome were investigated. RESULTS: There was a strong correlation between the detection of CTCs by both assays. CK-19mRNA-positive CTCs were detected in 201 (67%) patients and their detection was independent of various patients' clinico-pathological characteristics. The median progression-free survival (PFS; 9.2 vs 11.9 months (mo), P=0.003) and the overall survival (OS; 29.7 vs 38.9 mo, P=0.016) were significantly shorter in patients with detectable CK-19mRNA-positive CTCs compared with patients without detectable CTCs. Multivariate analysis demonstrated that oestrogen receptor status, performance status and detection of CTCs were emerged as independent prognostic factors associated with decreased PFS and OS. CONCLUSION: The detection of CK-19mRNA-positive CTCs in patients with MBC before front-line therapy could define a subgroup of patients with dismal clinical outcome.

Trastuzumab decreases the incidence of clinical relapses in patients with early breast cancer presenting chemotherapy-resistant CK-19mRNA-positive circulating tumor cells: results of a randomized phase II study.

BACKGROUND: Since the detection of circulating tumor cells (CTCs) which express HER2 is an adverse prognostic factor in early breast cancer patients, we investigated the effect of trastuzumab on patients' clinical outcome. PATIENTS AND METHODS: Seventy five women with HER2 (-) breast cancer and detectable CK19 mRNA-positive CTCs before and after adjuvant chemotherapy, were randomized to receive either trastuzumab (n=36) or observation (n=39). CK19 mRNA-positive CTCs were detected by RT-PCR and double stained CK(+)/HER2(+) cells by immunofluorescence. The primary endpoint was the 3-year disease-free survival rate. RESULTS: Fifty-one (89%) of the 57 analyzed patients had HER2-expressing CTCs. After trastuzumab administration, 27 of 36 (75%) women became CK19 mRNA-negative compared to seven of 39 (17.9%) in the observation arm (p=0.001). After a median follow up time of 67.2 months, four (11%) and 15 (38%) relapses were observed in the trastuzumab and observation arm, respectively (p=0.008); subgroup analysis indicated that this effect was mainly confined to women with >3 involved axillary lymph nodes (p=0.004). The median DFS was also significantly higher for the trastuzumab-treated patients (p=0.008). CONCLUSION: Administration of trastuzumab can eliminate chemotherapy-resistant CK19 mRNA-positive CTCs, reduce the risk of disease recurrence and prolong the DFS.

Detection of cytokeratin-19 mRNA-positive cells in the peripheral blood and bone marrow of patients with operable breast cancer.

BACKGROUND: To compare detection rates and evaluate the clinical relevance of cytokeratin-19 (CK-19) mRNA-positive cells in the peripheral blood (circulating tumour cells, CTCs) and bone marrow (disseminated tumour cells; DTCs) of patients with early breast cancer. METHODS: Paired samples of peripheral blood and bone marrow were obtained from 165 patients with stage I-II breast cancer before the initiation of adjuvant chemotherapy. In 84 patients, paired blood and bone marrow samples were also available after chemotherapy. The detection of CK-19 mRNA-positive CTCs and DTCs was assessed by real-time PCR. RESULTS: CK-19 mRNA-positive CTCs and DTCs were detected in 55.2 and 57.6% of patients before chemotherapy, respectively. After chemotherapy, CTCs and DTCs were identified in 44 (52.4%) and 43 (51.2%) of the 84 patients, respectively. There was a 93.9% (McNemar; P=0.344) and 72.6% (McNemar; P=0.999) concordance between blood and bone marrow samples before and after chemotherapy, respectively. The detection of CK-19 mRNA-positive CTCs or DTCs before chemotherapy was associated with decreased overall survival (P=0.024 and P=0.015, respectively). In addition, their simultaneous detection was also associated with an increased incidence of disease-related death and decreased overall survival (P=0.016). CONCLUSIONS: The detection of CK-19 mRNA-positive CTCs using reverse transcription-PCR (RT-PCR) both before and after chemotherapy is correlated with the detection of CK-19 mRNA-positive DTCs in patients with early-stage breast cancer. The determination of the CTC status by RT-PCR conveys clinically relevant information that is not inferior to DTC status and, owing to the ease of sampling, warrants further evaluation as a tool for monitoring minimal residual disease.

Clinical relevance of circulating CK-19 mRNA-positive cells detected during the adjuvant tamoxifen treatment in patients with early breast cancer.

BACKGROUND: The purpose of this study was to evaluate the effect of adjuvant treatment with tamoxifen on the CK-19 mRNA+ cells in patients with early-stage breast cancer. PATIENTS AND METHODS: CK-19 mRNA+ cells were prospectively and longitudinally detected using a specific real-time PCR assay for CK-19 mRNA in 119 patients with estrogen and/or progesterone receptor-positive tumors during the period of tamoxifen administration. RESULTS: Twenty-two (18.5%) patients had detectable CK-19 mRNA+ cells after the completion of adjuvant chemotherapy and in 15 (68.2%) of them adjuvant tamoxifen could not eliminate these cells (persistently positive). In 68 (57.1%) patients, no CK-19 mRNA+ cells could be detected throughout the follow-up period (persistently negative). Seven (46.7%) of the 15 persistently positive and six (8.8%) of the 68 persistently negative patients developed disease recurrence (P = 0.00026). Persistency of CK-19 mRNA+ cells was associated with a significantly lower median disease-free interval (P = 0.0001) and overall survival (P = 0.0005). Multivariate analysis revealed that the detection of CK-19 mRNA+ cells during the administration of tamoxifen was associated with an increased risk of relapse [hazard ratio (HR) = 22.318, P = 0.00006] and death (HR = 13.954, P < 0.00001). CONCLUSIONS: The detection of CK-19 mRNA+ cells throughout the period of adjuvant tamoxifen treatment is an independent poor prognostic factor in patients with early breast cancer.

Prognostic value of chemotherapy-resistant CK19mRNA-positive circulating tumor cells in patients with advanced/metastatic non-small cell lung cancer.

BACKGROUND: The detection of circulating tumor cells (CTCs) is of prognostic significance in several tumor types. The present study evaluated the detection and the clinical relevance of CK19mRNA(+) CTCs in patients with advanced/metastatic non-small cell lung cancer before and after front-line chemotherapy. PATIENTS AND METHODS: Peripheral blood was obtained from 642 patients with treatment-naïve unresectable stage IIIB and IV non-small cell lung cancer and from 455 patients after the completion of 1st line chemotherapy. RNA was extracted from peripheral blood mononuclear cells and the detection of CK19mRNA-positive cells was performed using a quantitative PCR assay. RESULTS: Based on the detection limit of the assay, 167 (26.0%) patients had detectable CK19mRNA(+) CTCs at baseline. The detection of CK19mRNA(+) CTCs before treatment was not associated with the clinical outcome, but their detection at the end of chemotherapy was associated with significantly decreased PFS and OS [PFS: 2.6 vs 3.8 months (p = 0.008); OS: 5.7 vs 10.0 months (p = 0.006) for CK19mRNA(+) vs CK19mRNA(-) patients, respectively]. Multivariate analysis revealed that the detection of CK19mRNA(+) CTCs both before and after chemotherapy emerged as an independent factor associated with reduced PFS (HR: 1.778; p < 0.001) and OS (HR: 1.608; p = 0.001). CONCLUSION: The detection of peripheral blood CK19mRNA(+) CTCs before and after the completion of front-line chemotherapy is an adverse prognostic factor associated with poor clinical outcome in patients with stage IIIB/IV non-small cell lung cancer.

Molecular detection of cytokeratin-19-positive cells in the peripheral blood of patients with operable breast cancer: evaluation of their prognostic significance.

PURPOSE: To evaluate the prognostic significance of molecular detection of cytokeratin 19 (CK-19) mRNA-positive cells by nested reverse transcriptase polymerase chain reaction (RT-PCR) in the peripheral blood of women with stages I and II breast cancer before adjuvant chemotherapy. PATIENTS AND METHODS: The sensitivity and specificity of CK-19 mRNA detection by nested RT-PCR were investigated using MCF-7 and ARH-77 cells and blood from healthy women and patients with hematologic malignancies, metastatic colorectal cancer, and early and metastatic breast cancer. Peripheral blood from 148 patients with operable breast cancer, obtained before initiation of any adjuvant therapy, was tested for the presence of CK-19 mRNA-positive cells. RESULTS: The nested RT-PCR assay for CK-19 mRNA detected one MCF-7 tumor cell in 10(6) normal peripheral blood mononuclear cells in four of five experiments; no signal was detected with the CK-19-negative ARH-77 cells. CK-19 mRNA was detected in the peripheral blood of 3.7% of healthy blood donors, 14.3% of patients with hematologic malignancies, and 3.2% of patients with metastatic colorectal cancer. Detection rates for CK-19 mRNA-positive cells in the bone marrow/blood of patients with early or metastatic breast cancer were 63%/30% and 74%/52%, respectively. For stages I and II breast cancer, detection of CK-19-positive cells in the peripheral blood before adjuvant therapy was associated with reduced disease-free interval (P =.0007) and overall survival (P =.01). In multivariate analysis, detection of peripheral-blood CK-19-positive cells was an independent prognostic factor for disease relapse and death. CONCLUSION: Molecular detection of CK-19 mRNA-positive cells by RT-PCR in the peripheral blood of patients with stages I and II breast cancer before initiation of adjuvant therapy has independent prognostic value as a marker of poor clinical outcome.

Characterization of interleukin 2 receptors on B-cell chronic lymphocytic leukemia cells.

The expression and function of IL-2R chains expressed on B-cell chronic lymphocytic leukemia (B-CLL) cells were analyzed. IL-2R alpha was expressed in 31 out of 34 studied cases; in 17 cases more than 50% of the cells were positive whereas in three cases the proportion of IL-2R alpha+ cells was less than 10%. In two patients, 6 and 13% of the cells were IL-2R beta+, in six other cases only 2-3% of the B-CLL cells could be stained with the TU-27 moAb whereas in all other cases no positive cells could be detected. Equilibrium binding experiments using 125I-rIL2 revealed high (seven out of 15 studied cases), intermediate (four out of 15 cases) and low (five out of 15 cases) affinity IL-2R. The number of high and intermediate affinity IL-2R was low (range: 145-800 and 40-2800 binding sites/cells, respectively). In all cases investigated, both IL-2R alpha and IL-2R beta chain mRNA could be detected, although their quantity was variable from patient to patient. Exogenous recombinant IL-2 induced, in a dose-response manner, cell proliferation in ten out of 23 cases and this effect was independent of the expression of IL-2R alpha; however, only cells expressing high affinity IL-2R could respond to exogenous rIL-2. Moreover, anti-IL-2R alpha moAb could inhibit both spontaneous (in three out of five cases) and IL-2-induced (in five out of five cases) B-CLL cell proliferation. These findings demonstrate that in a subgroup of B-CLL, leukemic cells are dependent on the IL-2/IL-2R system whereas in another group, although cells expressed functional IL-2 binding sites, they could not respond to the mitogenic signal of IL-2.

Intracytoplasmic detection of the Tac (p55) chain of interleukin-2 receptor in pre-B leukemic cells associated with a constitutive expression of Tac mRNA.

The pre-B Reh-6 leukemic cells do not express membrane interleukin-2 (IL-2)-R alpha (Tac or p55) chain; however, their incubation with PMA induces the expression of both high and low affinity IL-2-R. Northern analysis of nonstimulated Reh-6 as well as leukemic cells from patients with acute B cell precursor lymphoblastic leukemia displayed a constitutive expression of p55 mRNA transcripts, which could be enhanced by PMA. Both actinomycin-D and cycloheximide could abrogate PMA-induced p55 membrane expression, suggesting the need for de novo mRNA and protein synthesis. The increased PMA-induced p55 mRNA accumulation was an early event (4 hr) and could be enhanced, specifically, by rIL-2 because anti-Tac moAb inhibited this rIL-2-mediated effect. Immunofluorescence and cross-linking studies using 125I-rIL-2 failed to reveal membrane-associated p55 protein on both Reh-6 and patients' leukemic cells. Conversely, immunogold staining and electron microscopy studies, revealed p55 immunoreactive molecules in the cytoplasm but not in the nucleus of all Reh-6 cells. Using a sensitive EIA, p55 molecules could be detected in cell lysates but not the culture supernatants of Reh-6 cells, suggesting that p55 was not released into the culture medium. These results indicate that constitutively expressed p55 mRNA on pre-B leukemic cells is translated into a relative immunoreactive protein that cannot be expressed on cell surface for unknown, yet, reasons.

Autocrine IL-2-dependent growth of a newly established CD3+, CD16-, CD56+, CD57+, J(H)-, TCRbeta-, TCRgamma- leukemia cell line (NOI-90).

Leukemic cells from a 45-year-old male patient with a CD3+, CD56+, CD57+, CD7+ acute lymphoblastic leukemia were cultured in vitro in the absence of any added growth factor for up to 6 years and a continuous lymphoblastoid cell line (NOI-90) was established. NOI-90 cells have the same phenotype and karyotype as initial leukemic cells. Southern blot of DNA from NOI-90 cells showed that TCRbeta, TCRgamma, and J(H) were in germ line. Two and 25% of NOI-90 cells were positive when stained with the IOT14 and 7G7/B6 moAbs, which recognize the CD25 molecule (IL-2R alpha chain); moreover, 4% and 13% of the cells were positive when stained with the TU-27 and mik beta3 moAbs which recognize the CD122 molecule (IL-2Rbeta chain). Equilibrium binding experiments with radiolabelled IL-2 revealed the presence of a small number of high affinity IL-2R on both fresh and continuously growing cells. Media conditioned by NOI-90 cells could induce proliferation of an IL-2-dependent cell line and this IL-2 activity could be detected by a sensitive immunoenzymatic assay using antibodies recognizing distinct epitopes of IL-2. Moreover, IL-2 activity could be adsorbed by immunoaffinity on anti-IL-2 polyclonal purified IgG and the retained molecule displayed a m.w. of 14.5 kDa in SDS-PAGE. In addition, IL-2 immunoreactive molecules could be revealed in the cytoplasm of the cells. Finally, IL-2 fixed on the cell membrane could be detected by indirect immunofluorescence. Although added IL-2 could not induce cell proliferation, monoclonal antibodies against CD25, CD122 and IL-2 could specifically inhibit spontaneous cell proliferation in a dose-dependent manner. NOI-90 cells failed to demonstrate any cytotoxic activity against the K-562, Raji or Daudi cells. These findings indicate that NOI-90 cells are of non-T, non-B, origin lacking NK activity but proliferate under an autocrine pathway which involves, at least partly, the IL-2/IL-2R system.

Interleukin 2 production and interleukin 2 receptor expression by human immature leukemic T cells.

In order to determine the role of interleukin 2 (IL2) on the proliferation of leukemic cells from patients with T-cell acute lymphoblastic leukemia (T-ALL) we studied the production of IL2, the function of IL2 receptors (IL2R) expressed on T-ALL cells and their IL-2-dependent in vitro proliferation. Leukemic cells from six out of 17 T-ALL/T-cell non-Hodgkin's lymphoma patients with a prothymocyte (stage I) or a mature thymocyte (stage III), but not with a common thymocyte (stage II) phenotype, could proliferate, in a dose-dependent manner, in response to recombinant IL2 (rIL2) and anti-Tac and TU27 moAbs as well as polyclonal anti-IL2 purified immunoglobulin G could inhibit this IL2-induced cell proliferation. Both crude or/and Amicon-concentrated media conditioned by T-ALL cells from 10 out of 13 tested patients contained IL2 activity as assessed by colorimetric biological and immunoenzymatic assays; this biologic activity was due to a 14.5 kDa molecule adsorbed by anti-IL2 antibodies in an immunoaffinity assay. Although less than 10% of fresh leukemic cells expressed IL2R alpha (Tac) chain, a 24 h cell incubation in the absence of any mitogenic stimulation induced IL2R alpha chain expression in five out of 13 patients (11-83% Tac+ cells). Morever, Tac mRNA transcripts could be detected in fresh cells from all 10 patients tested. Staining of fresh leukemic cells with an IL-2R beta-chain-specific monoclonal antibody and flow cytometry analysis revealed that 4-13% of leukemic cells were positive. Binding experiments with 125I-rIL2 showed a small number of high affinity IL2R on fresh cells from three T-ALL patients (114-200 sites/cell, dissociation constant = 101-181 pm). Finally, antibodies against IL2R alpha, IL2R beta and IL2 could inhibit both IL2 driven and spontaneous cell proliferation of most patients' T-ALL cells, although in some cases an heterogenous pattern of inhibition was observed. Taken together, these findings strongly suggest that an IL2/IL2R-dependent mechanism could be involved in the proliferation of some T-ALL cells.

Production of a tac inhibitory activity by adherent cells of HIV-infected subjects at different clinical stages.

Studying the mechanisms of the impaired T-cell colony growth from HIV-infected subjects, we have demonstrated that depletion of adherent cells from some patients' peripheral blood mononuclear cells enhanced the plating efficiency of T colony-forming cells. We report here that media conditioned by patients' cells but not normal adherent cells could inhibit the expression of the interleukin-2 receptor alpha (IL-2R alpha) chain but not the IL-2R beta chain in a dose-dependent manner. This inhibitory activity was produced by macrophage-monocyte cells since they displayed the My9+ My7+ OKM1+ phenotype and since adherent cell depletion by complement-mediated cytotoxicity with the My9 monoclonal antibody completely abrogated production of the inhibitory activity. A similar inhibitory activity, which could not be recognized by anti-p24 or anti-gp 120 monoclonal antibody or purified human anti-HIV immun]gobulin G in Western blot assays, could also be detected in culture supernatants of in vitro HIV-infected normal adherent and U937 leukemic cells. Production of IL-2R alpha chain inhibitory activity was associated with a decreased mitogen-induced expression of IL-2R alpha chain on patients' PBMC in 8 of 10 studied cases. Its production could be detected in 82, 58, and 91% of media conditioned by adherent cells from stage II, III, and IV patients, respectively. The amount of IL-2R alpha chain inhibitor released by patients' adherent cells increased during the deterioration of the patients' clinical status, and zidovudine treatment completely abrogated its production in all patients. These findings strongly suggest that production of IL-2R alpha chain inhibitory activity is involved in the pathophysiology of the impaired T-cell responses during HIV infection and could be of clinical relevance during the patients' follow-up.

Phorbol myristate acetate induces both high affinity and low affinity interleukin 2-receptors on a pre-B leukemic cell line.

The human pre-B leukemic cell line Reh6 does not constitutively express the Tac molecule (p55), which is one of the two polypeptide chains of the interleukin 2-receptor (IL2-R). Cell incubation with Phorbol Myristate Acetate (PMA) induces expression of the Tac molecule in a dose and time-dependent manner. Binding experiments with radiolabelled recombinant IL2 (rIL2) revealed both high and low affinity IL2-R (225 +/- 105 sites/cell with a Kd of 130 +/- 51 pM and 24060 sites/cell with a Kd of 17.3 nM respectively), whereas unstimulated Reh6 cells only expressed intermediate affinity Reh6 cells revealed the presence of two polypeptide chains of mol. wts 55,000 (Tac molecule) and 70,000, as in normal activated T cells, while the 70,000 mol. wt chain alone was observed in unstimulated Reh6 cells. IL2-R-bearing Reh6 cells could absorb rIL2 in a dose-dependent manner and this absorption was inhibited by a monoclonal antibody against the Tac molecule (anti-Tac). Moreover, partial internalization of IL2 bound under high affinity conditions occurred at 37 degrees C. IL2-R expressed on PMA-induced cells were functional since rIL2 specifically enhanced the proliferation in vitro of PMA-treated cells in semi-solid but not liquid cultures. These findings thus demonstrate an IL2-dependent mechanism of proliferation in vitro of pre-B leukemic cells induced by PMA, which can express high affinity, functional IL2-R.

Quantitative RT-PCR luminometric hybridization assay with an RNA internal standard for cytokeratin-19 mRNA in peripheral blood of patients with breast cancer.

OBJECTIVES: To develop a highly sensitive quantitative RT-PCR hybridization assay for the determination of CK-19 mRNA in peripheral blood of patients with breast cancer. PATIENTS AND METHODS: Quantification of CK-19 mRNA was based on the coamplification of CK-19 mRNA with a recombinant CK-19 RNA internal standard (CK-19 RNA-IS) through RT-PCR. The biotinylated amplification products were immobilized on steptavidin coated wells, hybridized with digoxigenin labeled probes and determined through an antidigoxigenin antibody conjugated to alkaline phosphatase by luminometric detection. The developed luminometric hybridization assay was validated with samples containing total RNA of known amounts from CK-19 expressing cells (MCF-7) in the presence of 1 microg total RNA isolated from peripheral blood mononuclear cells (PBMC) of healthy controls and a constant amount of CK-19 RNA-IS. The method was applied for the quantitative determination of CK-19 mRNA in the peripheral blood of 26 healthy volunteers, 14 patients with stage IV breast cancer and 37 patients with stage I/II breast cancer before chemotherapy. RESULTS: Luminescence ratios for CK-19 mRNA and CK-19 RNA-IS were linearly related to the number of MCF-7 cells within the range of 1 to 2000 cells. The overall reproducibility of the assay (between-run) varied between 8.9% and 13.4%. The method can clearly detect CK-19 mRNA from 1 MCF-7 cell in the presence of 10(6) normal PBMC and is highly specific as none of the 26 healthy controls tested had detectable CK-19 mRNA levels, while 10 out of 14 (71.4%) and 9 out of 37 (24.3%) patients with stage IV and stage I/II breast cancer, respectively, were tested positive. CONCLUSION: The developed quantitative RT-PCR hybridization assay for CK-19 is reproducible, highly sensitive and specific, and can be used for a large-scale prospective evaluation of clinical samples.

Molecular detection of cancer cells in the peripheral blood of patients with breast cancer: comparison of CK-19, CEA and maspin as detection markers.

PURPOSE: To investigate and compare the diagnostic value of the detection of cytokeratin 19 (CK-19), carcinoembryonic antigen (CEA) and maspin mRNA by nested RT-PCR in the peripheral blood of women with breast cancer. MATERIALS AND METHODS: The tumor cell lines MCF-7 and LOVO were used in an experimental tumor cell dilution model to determine the sensitivity of the nested RT-PCR for the 3 detection markers. RT-PCR analysis was performed in the peripheral blood of 54 healthy female blood donors, 28 patients with hematological malignancies, 31 with metastatic colorectal cancer, 75 with operable and 50 with metastatic breast cancer before receiving any cytotoxic chemotherapy, as well as in the bone marrow aspirates of 61 breast cancer patients. RESULTS: Nested RT-PCR for CK-19 mRNA presented the highest sensitivity by detecting 1 tumor cell amongst 10(6) PBMC in 4 out of 5 experiments. CK-19 mRNA was detected in the peripheral blood of 3.7% of female blood donors, 14.3% of hematological malignancies, 32% of operable and 42% of metastatic breast cancer patients. CEA mRNA was undetectable in the blood of female blood donors but was detected in blood samples of 3.5% of hematological malignancies, 19.3% of colorectal cancer and 10% of breast cancer patients. Maspin mRNA was undetectable in the blood of female blood donors, patients with hematological malignancies and colorectal cancer but was detected in 9.3% of operable and 14% of metastatic breast cancer patients. Maspin mRNA positivity correlated with tumor size in patients with early stage breast cancer (p = 0.057). The detection rates of CK-19 and maspin mRNA in bone marrow aspirates were 33% and 11% for operable and 62% and 9% for metastatic breast cancer, respectively. During follow-up, 27.4% of blood samples were positive for CK-19 mRNA versus 10.7% for maspin mRNA in patients with operable breast cancer with a concordance rate of only 12.7% for positives and 86% for negatives. CONCLUSION: RT-PCR positivity for CK-19 mRNA is the most sensitive detection marker for occult tumor cells in operable and metastatic breast cancer, although nested RT-PCR for maspin mRNA appears to be more specific.

Effect of front-line chemotherapy on circulating CK-19 mRNA-positive cells in patients with metastatic breast cancer.

PURPOSE: To evaluate the effect of front-line chemotherapy on CK-19mRNA+ circulating tumor cells (CTCs) and their relevance in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: The presence of CK-19mRNA+ CTCs was assessed using a real-time RT-PCR assay in 298 previously untreated patients with MBC before and after the administration of front-line chemotherapy. RESULTS: CK-19mRNA+ CTCs were detected in the blood of 199 (66.8 %) and 148 (49.7 %) patients before and after chemotherapy, respectively. There was no correlation between the detection of CK-19mRNA+ CTCs after chemotherapy and the various known clinicopathologic parameters except with HER2 status. The incidence of detection of CK-19mRNA+ CTCs was significantly decreased after the administration of 3 (47.8 %; p < 0.001) or 6 (44.3 %; p = 0.001) chemotherapy cycles. The persistent detection of >2.25 CK-19mRNA+ CTCs both before and after chemotherapy (persistently high group) was associated with a significantly (p = 0.003) decreased overall survival. In addition, chemotherapy-induced decrease of CK-19mRNA+ CTCs (≤2.25 CTCs) was associated with a better survival (47 vs 34 months; p < 0.001). Failure of chemotherapy to decrease the CK-19mRNA+ CTCs ≤2.25 was associated with decreased overall survival (HR 1.405, 95 % CI 1.044-1.891; p = 0.025) whereas in multivariate analysis the persistence of >2.25 CTCs both before and after chemotherapy was emerged as an independent prognostic factor (HR 1.661, 95 % CI 1.070-2.579; p = 0.024). CONCLUSION: Detection of CK-19mRNA+ CTCs after the completion of front-line chemotherapy in patients with MBC is associated with poor survival and may be a useful tool for the evaluation of front-line chemotherapy.

Synthesis of TiO2 nano-powders prepared from purified sulphate leach liquor of red mud.

The research work presented in this paper is focused on the development of a purification process of red mud sulphate leach liquor for the recovery of titanium oxide (TiO(2)) nano-powders in the form of anatase. Initially, titanium was extracted over iron and aluminium from the leach liquor by solvent extraction using Cyanex 272 in toluene, at pH: 0.3 and T: 25°C, with 40% extractant concentration. Stripping of the loaded, with titanium, organic phase was carried out by diluted HCl (3 mol/L) at ambient temperature. Finally, the recovery of titanium nano-powder, in the form of anatase, was performed by chemical precipitation at pH: 6 and T: 95°C, using 10 wt% MgO pulp as neutralizing agent. The produced precipitates were characterized by X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric/differential thermal analysis (TGA/DTA). Their morphological characteristics and microstructure were studied by scanning electron microscopy (SEM). High grade titanium white precipitate, in the form of anatase, was obtained. Iron concentration in the precipitate did not exceed 0.3%, whereas no aluminium was detected.

Circulating HER2 mRNA-positive cells in the peripheral blood of patients with stage I and II breast cancer after the administration of adjuvant chemotherapy: evaluation of their clinical relevance.

BACKGROUND: The purpose of this study was to evaluate the prognostic value of circulating tumor cells (CTCs) expressing HER2 messenger RNA (mRNA) after the administration of adjuvant chemotherapy in women with operable breast cancer. PATIENTS AND METHODS: HER2 mRNA-positive CTCs were detected by nested RT-PCR in the peripheral blood of 214 patients with stage I and II breast cancer after the completion of adjuvant chemotherapy. RESULTS: HER2 mRNA-positive CTCs were detected in 45 (21%) patients. Adjuvant chemotherapy could eliminate HER2 mRNA-positive CTCs in 16 (30.2%) prechemotherapy-positive patients. Moreover, HER2 mRNA-positive CTCs were detected in eight (5%) of 161 prechemotherapy-negative patients. The detection of HER2 mRNA-positive CTCs after chemotherapy was associated with reduced disease-free interval (DFI) (P = 0.006) but not with overall survival (P = 0.2); this effect was mainly observed in node-negative patients (P = 0.04) and to a lesser extent in node-positive (P = 0.06). Multivariate analysis revealed that the detection of HER2 mRNA-positive CTCs was an independent predictive factor for DFI (hazard ratio 3.238, P < 0.0005). CONCLUSIONS: The detection of HER2 mRNA-positive CTCs after the completion of adjuvant chemotherapy may provide clinically useful information concerning the efficacy of treatment and the prognosis of patients with operable breast cancer.

Detection of CK-19 mRNA-positive cells in the peripheral blood of breast cancer patients with histologically and immunohistochemically negative axillary lymph nodes.

BACKGROUND: To investigate the incidence of direct hematogenous spread of cancer cells in patients with early-stage breast cancer by studying the presence of occult tumor cytokeratin-19 (CK-19) mRNA(+) cells in the peripheral blood in relation to the status of sentinel (SLNs) and (ALNs) axillary lymph nodes. PATIENTS AND METHODS: SLNs and ALNs from 111 patients with operable stage I-II breast adenocarcinoma were evaluated for the presence of tumor cells by hematoxylin-eosin (H&E) staining and, if negative, by immunohistochemistry (IHC) using an anti-CK-19 antibody. Peripheral blood was also analyzed for the presence of CK-19 mRNA(+) cells by nested RT-PCR, before the initiation of adjuvant treatment and in CK-19 mRNA(+) patients following the completion of adjuvant chemotherapy and hormonal treatment. RESULTS: After both H&E staining and IHC analysis, 29 (26%) patients were ALN negative (N0). In 78 (70%) patients H&E staining and in four (3.6%) IHC analysis revealed tumors cells, and these patients were considered as ALN positive (N+). Peripheral blood CK-19 mRNA(+) cells were detected in nine (31%) out of 29 N0 and in 31 (38%) out of 82 N + patients (P=0.5) before any adjuvant treatment. Adjuvant chemotherapy and hormone treatment resulted in the disappearance of the CK-19 mRNA(+) cells in all N0 patients and in 15 out of 31 N + patients. After a median follow-up of 40 months, all the N0 CK-19 mRNA(+) patients were relapse-free whereas four (13%) N + CK-19 mRNA(+) patients had relapsed. CONCLUSIONS: Direct hematogenous dissemination of occult tumor cells may occur in a substantial proportion of patients with early-stage breast cancer. The prognostic implication of the detection of these cells requires long follow-up periods and further studies.

Triethyllead-induced inhibition of proliferation of normal human lymphocytes through decreased expression of the Tac chain of interleukin 2 receptor.

Triethyllead (Et3Pb+) in concentrations 10(-5) to 10(-6) M has been shown to inhibit several key cellular molecular systems. In order to evaluate the effect of Et3Pb+ on the human immune system, the mitogen-induced cell proliferation of peripheral blood mononuclear cells was studied in the presence of Et3Pb+. Preincubation of normal T-lymphocytes with 10(-6) M Et3Pb+ for 1-4 h, which has been shown to be non-cytotoxic, was sufficient to inhibit subsequent mitogenic-induced cell growth. The Et3Pb(+)-induced impairement of the in vitro proliferation of mitogen-activated normal T-cells was due to a dose-dependent decreased expression of the p55 polypeptide chain (Tac molecule) of the interleukin-2 receptor (IL-2-R), which could not be enhanced by exogeneously added recombinant interleukin 2 (rIL-2). Conversely, the same concentrations of Et3Pb+ could not inhibit the mitogen-induced expression of MHC class II molecules and the transferin receptor on activated T-cells. The impaired membrane expression of p55 on T-cells induced by Et3Pb+ was due to a decrease of Tac mRNA transcripts as showed by Northern blot analysis. This effect seems to be specific since in parallel experiments Et3Pb+ could not inhibit both the accumulation of actin mRNA and the production of IL-2 by Et3Pb(+)-treated mitogen-activated cells. The effect of this organolead compound was also associated with a dose-dependent decrease of the Na(+)-K(+)-ATPase activity of normal lymphocytes. These results indicate that Et3Pb+ could affect specifically T-cell proliferative responses through an imbalance of the IL-2/IL-2-R system.