Reduction in new metastases in breast cancer with adjuvant clodronate treatment

BACKGROUND

Bisphosphonates are effective against the increased bone resorption caused by certain diseases because they inhibit the activity of osteoclasts. In patients who have breast cancer and metastatic bone disease, the bisphosphonate clodronate (clodronic acid) reduces the frequency of skeletal complications. Experiments in animals and preliminary clinical observations indicate that early clodronate therapy reduces the incidence of new bony metastases in breast cancer. We investigated the effects of clodronate on the incidence and extent of new metastases in patients with breast cancer.

METHODS

Between 1990 and 1995, 302 patients with primary breast cancer and tumor cells in the bone marrow (the presence of which is a risk factor for the development of distant metastases) were randomly assigned to receive clodronate at a dose of 1600 mg per day orally for two years (157 patients) or standard follow-up (145 patients). The median length of observation was 36 months. All patients in both groups received standard surgical treatment and customary hormonal therapy or chemotherapy.

RESULTS

Distant metastases were detected in 21 patients in the clodronate group and in 42 patients in the control group (P<0.001). The incidence of both osseous and visceral metastases was significantly lower in the clodronate group than in the control group (P=0.003 for both osseous and visceral metastases). Six patients in the clodronate group died, as did 22 in the control group (P=0.001). The mean number of bony metastases per patient in the clodronate group was roughly half that in the control group (3.1 vs. 6.3).

CONCLUSIONS

Clodronate can reduce the incidence and number of new bony and visceral metastases in women with breast cancer who are at high risk for distant metastases.

Mutations in CYP24A1 and idiopathic infantile hypercalcemia

BACKGROUND

Vitamin D supplementation for the prevention of rickets is one of the oldest and most effective prophylactic measures in medicine, having virtually eradicated rickets in North America. Given the potentially toxic effects of vitamin D, the recommendations for the optimal dose are still debated, in part owing to the increased incidence of idiopathic infantile hypercalcemia in Britain in the 1950s during a period of high vitamin D supplementation in fortified milk products. We investigated the molecular basis of idiopathic infantile hypercalcemia, which is characterized by severe hypercalcemia, failure to thrive, vomiting, dehydration, and nephrocalcinosis.

METHODS

We used a candidate-gene approach in a cohort of familial cases of typical idiopathic infantile hypercalcemia with suspected autosomal recessive inheritance. Identified mutations in the vitamin D-metabolizing enzyme CYP24A1 were evaluated with the use of a mammalian expression system.

RESULTS

Sequence analysis of CYP24A1, which encodes 25-hydroxyvitamin D 24-hydroxylase, the key enzyme of 1,25-dihydroxyvitamin D(3) degradation, revealed recessive mutations in six affected children. In addition, CYP24A1 mutations were identified in a second cohort of infants in whom severe hypercalcemia had developed after bolus prophylaxis with vitamin D. Functional characterization revealed a complete loss of function in all CYP24A1 mutations.

CONCLUSIONS

The presence of CYP24A1 mutations explains the increased sensitivity to vitamin D in patients with idiopathic infantile hypercalcemia and is a genetic risk factor for the development of symptomatic hypercalcemia that may be triggered by vitamin D prophylaxis in otherwise apparently healthy infants.

Exemestane is superior to megestrol acetate after tamoxifen failure in postmenopausal women with advanced breast cancer: results of a phase III randomized double-blind trial. The Exemestane Study Group

PURPOSE

This phase III, double-blind, randomized, multicenter study evaluated the efficacy, pharmacodynamics, and safety of the oral aromatase inactivator exemestane (EXE) versus megestrol acetate (MA) in postmenopausal women with progressive advanced breast cancer who experienced failure of tamoxifen.

PATIENTS AND METHODS

A total of 769 patients were randomized to EXE 25 mg/d (n = 366) or MA (n = 403) 40 mg four times daily. Tumor response, duration of tumor control, tumor-related signs and symptoms (TRSS), quality of life (QOL), survival, and tolerability were evaluated.

RESULTS

Overall objective response (OR) rates were higher in patients treated with EXE than in those treated with MA (15.0% v 12.4%); a similar trend was noted in patients with visceral metastases (13.5% v 10.5%). Median survival time was significantly longer with EXE (median not reached) than with MA (123.4 weeks; P =.039), as were the median duration of overall success (OR or stable disease > or = 24 weeks; 60.1 v 49.1 weeks; P =.025), time to tumor progression (20.3 v 16.6 weeks; P =.037), and time to treatment failure (16.3 v 15.7 weeks; P =.042). Compared with MA, there were similar or greater improvements in pain, TRSS, and QOL with EXE. Both drugs were well tolerated. Grade 3 or 4 weight changes were more common with MA (17.1% v 7.6%; P =.001).

CONCLUSION

EXE prolongs survival time, time to tumor progression, and time to treatment failure compared with MA and offers a well-tolerated treatment option for postmenopausal women with progressive advanced breast cancer who experienced failure of tamoxifen.

25-Hydroxyvitamin D-24-hydroxylase (CYP24A1): its important role in the degradation of vitamin D

CYP24A1 is the cytochrome P450 component of the 25-hydroxyvitamin D(3)-24-hydroxylase enzyme that catalyzes the conversion of 25-hydroxyvitamin D(3) (25-OH-D(3)) and 1,25-dihydroxyvitamin D(3) (1,25-(OH)(2)D(3)) into 24-hydroxylated products, which constitute the degradation of the vitamin D molecule. This review focuses on recent data in the CYP24A1 field, including biochemical, physiological and clinical developments. Notable among these are: the first crystal structure for rat CYP24A1; mutagenesis studies which change the regioselectivity of the enzyme; and the finding that natural inactivating mutations of CYP24A1 cause the genetic disease idiopathic infantile hypercalcemia (IIH). The review also discusses the emerging correlation between rising serum phosphate/FGF-23 levels and increased CYP24A1 expression in chronic kidney disease, which in turn underlies accelerated degradation of both serum 25-OH-D(3) and 1,25-(OH)(2)D(3) in this condition. This review concludes by evaluating the potential clinical utility of blocking this enzyme with CYP24A1 inhibitors in various disease states.

Micrometastatic breast cancer cells in bone marrow at primary surgery: prognostic value in comparison with nodal status

BACKGROUND

Approximately 30% of the patients with primary breast cancer who have no axillary lymph node involvement (i.e., lymph node negative) at the time of surgery will relapse within 10 years; 10%-20% of the patients with distant metastases will be lymph node negative at surgery. Axillary lymph node dissection, as a surgical procedure, is associated with frequent complications. A possible alternative to nodal dissection in terms of prognosis may be the immunocytochemical detection of tumor cells in bone marrow.

PURPOSE

In a prospective study, the value of tumor cell detection (TCD) in bone marrow was compared with axillary lymph node dissection in the prognosis of primary breast cancer after surgery.

METHODS

Data from 727 patients with primary, operable breast cancer were included in the analysis. All patients had surgery, including axillary lymph node dissection, from May 1985 through July 1994 at the Women's Hospital of the University of Heidelberg (Federal Republic of Germany). Bone marrow aspiration at two sites on each anterior iliac crest was performed immediately after surgery while the patients were under general anesthesia. Most patients received some type of systemic adjuvant therapy. The monoclonal antibody 2E11, directed against the polymorphic epithelial mucin TAG12, was used to detect tumor cells in bone marrow samples. The association of TCD with recognized prognostic indicators was evaluated by means of chi-squared tests. Survival without the development of distant metastases (i.e., distant disease-free survival) and overall survival were estimated by use of the Kaplan-Meier method; the logrank test was used to compare survival curves. A multivariate Cox regression analysis with stratification according to adjuvant treatment type was used to assess the independent prognostic value of TCD in bone marrow in relation to other variables. Reported P values are two-sided.

RESULTS

Tumor cells were detected in the bone marrow of 203 (55%) of 367 lymph node-positive patients and in 112 (31%) of 360 lymph node-negative patients. TCD was associated with larger tumors (P < .001), lymph node involvement (P = .001), and higher tumor grade (i.e., more undifferentiated) (P = .002). After a median follow-up of 36 months, patients with tumor cells in their bone marrow experienced reduced distant disease-free survival and overall survival (both P values < .001). TCD was an independent prognostic indicator for both distant disease-free survival and overall survival that was superior to axillary lymph node status, tumor stage, and tumor grade. Among patients with tumors less than 2 cm in diameter, TCD was the most powerful predictor of outcome.

CONCLUSIONS AND IMPLICATIONS

TCD in the bone marrow of patients with breast cancer is a valuable prognostic tool associated with negligible morbidity. Prospective randomized studies should be performed to determine whether TCD might replace axillary lymph node dissection in a defined subgroup of patients with small tumors.

Cytochrome P450-mediated metabolism of vitamin D

The vitamin D signal transduction system involves a series of cytochrome P450-containing sterol hydroxylases to generate and degrade the active hormone, 1α,25-dihydroxyvitamin D3, which serves as a ligand for the vitamin D receptor-mediated transcriptional gene expression described in companion articles in this review series. This review updates our current knowledge of the specific anabolic cytochrome P450s involved in 25- and 1α-hydroxylation, as well as the catabolic cytochrome P450 involved in 24- and 23-hydroxylation steps, which are believed to initiate inactivation of the vitamin D molecule. We focus on the biochemical properties of these enzymes; key residues in their active sites derived from crystal structures and mutagenesis studies; the physiological roles of these enzymes as determined by animal knockout studies and human genetic diseases; and the regulation of these different cytochrome P450s by extracellular ions and peptide modulators. We highlight the importance of these cytochrome P450s in the pathogenesis of kidney disease, metabolic bone disease, and hyperproliferative diseases, such as psoriasis and cancer; as well as explore potential future developments in the field.

CD44 variant exon epitopes in primary breast cancer and length of survival

CD44 designates a group of closely related cell-surface proteins generated by alternative splicing. We have previously shown that splice variants carrying sequences encoded by exon v6 are preferentially expressed in metastatic animal cancer cell lines and that they confer metastatic behaviour on non-metastatic animal tumour cell lines. In this study we set out to assess the expression of CD44 epitopes specific for variant exon sequences in human breast cancer and their potential for determining prognosis. We used affinity-purified polyclonal sera and four monoclonal antibodies raised against the human homologues of CD44 variant exon sequences to investigate the presence of CD44 on 100 primary invasive breast tumours, 12 local recurrences, 18 lymph node metastases, and normal tissue controls. Whereas normal mammary ductal epithelial cells and cells derived from hyperplastic lesions do not express CD44 variant exons, expression of v3, v5, and v6 epitopes was found in most tumour samples. The DIII (exon v6) epitope was present in 84% of the primary tumours and in 100% of axillary lymph node metastases and local recurrences. The presence of these CD44 epitopes is correlated with poor overall survival. 15 patients with exon-v6-negative tumours had good survival compared with 76 patients with exon-v6-positive tumours (p = 0.005; log rank test). Multivariate analysis showed that the CD44 epitope encoded by exon v6 was a good marker for prognosis independent of progesterone receptor, lymph node status, tumour size, and grade.

Widespread intraspecies cross-contamination of human tumor cell lines arising at source

We present a panoptic survey of cell line cross-contamination (CLCC) among original stocks of human cell lines, investigated using molecular genetic methods. The survey comprised 252 consecutive human cell lines, almost exclusively tumor-derived, submitted by their originators to the DSMZ and 5 additional cell repositories (CRs), using a combination of DNA profiling (4-locus minisatellite and multilocus microsatellite probes) and molecular cytogenetics, exploiting an interactive database (http://www.dsmz.de/). Widespread high levels of cross-contaminants (CCs) were uncovered, affecting 45 cell lines (18%) supplied by 27 of 93 originators (29%). Unlike previous reports, most CCs (42/45) occurred intraspecies, a discrepancy attributable to improved detection of the more insidious intraspecies CCs afforded by molecular methods. The most prolific CCs were classic tumor cell lines, the numbers of CCs they caused being as follows: HeLa (n = 11), T-24 (n = 4), SK-HEP-1 (n = 4), U-937 (n = 4) and HT-29 (n = 3). All 5 supposed instances of spontaneous immortalization of normal cells were spurious, due to CLCC, including ECV304, the most cited human endothelial cell line. Although high, our figure for CCs at the source sets a lower limit only as (i) many older tumor cell lines were unavailable for comparison and (ii) circulating cell lines are often obtained indirectly, rather than via originators or CRs. The misidentified cell lines reported here have already been unwittingly used in several hundreds of potentially misleading reports, including use as inappropriate tumor models and subclones masquerading as independent replicates. We believe these findings indicate a grave and chronic problem demanding radical measures, to include extra controls over cell line authentication, provenance and availability.

Goserelin versus cyclophosphamide, methotrexate, and fluorouracil as adjuvant therapy in premenopausal patients with node-positive breast cancer: The Zoladex Early Breast Cancer Research Association Study

PURPOSE

Current adjuvant therapies have improved survival for premenopausal patients with breast cancer but may have short-term toxic effects and long-term effects associated with premature menopause.

PATIENTS AND METHODS

The Zoladex Early Breast Cancer Research Association study assessed the efficacy and tolerability of goserelin (3.6 mg every 28 days for 2 years; n = 817) versus cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy (six 28-day cycles; n = 823) for adjuvant treatment in premenopausal patients with node-positive breast cancer.

RESULTS

Analysis was performed when 684 events had been achieved, and the median follow-up was 6 years. A significant interaction between treatment and estrogen receptor (ER) status was found (P =.0016). In ER-positive patients (approximately 74%), goserelin was equivalent to CMF for disease-free survival (DFS) (hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.84 to 1.20). In ER-negative patients, goserelin was inferior to CMF for DFS (HR, 1.76; 95% CI, 1.27 to 2.44). Amenorrhea occurred in more than 95% of goserelin patients by 6 months versus 58.6% of CMF patients. Menses returned in most goserelin patients after therapy stopped, whereas amenorrhea was generally permanent in CMF patients (22.6% v 76.9% amenorrheic at 3 years). Chemotherapy-related side effects such as nausea/vomiting, alopecia, and infection were higher with CMF than with goserelin during CMF treatment. Side effects related to estrogen suppression were initially higher with goserelin, but when goserelin treatment stopped, reduced to a level below that observed in the CMF group.

CONCLUSION

Goserelin offers an effective, well-tolerated alternative to CMF in premenopausal patients with ER-positive and node-positive early breast cancer.

Use of luteinising-hormone-releasing hormone agonists as adjuvant treatment in premenopausal patients with hormone-receptor-positive breast cancer: a meta-analysis of individual patient data from randomised adjuvant trials

BACKGROUND

Several trials have been done to assess treatment of premenopausal breast cancer with luteinising-hormone-releasing hormone (LHRH) agonists, but results have been inconclusive, especially for patients with hormone-receptor-positive cancer.

METHODS

We collected individual patients' data from published trials and did analyses focused on women with tumours positive for oestrogen receptor, progesterone receptor, or both. The main endpoints were recurrence and death after recurrence.

FINDINGS

We obtained data for 11 906 premenopausal women with early breast cancer randomised in 16 trials. When used as the only systemic adjuvant treatment, LHRH agonists did not significantly reduce recurrence (28.4% relative reduction, 95% CI consistent with 50.5% reduction to 3.5% increase, p=0.08) or death after recurrence (17.8%, 52.8% reduction to 42.9% increase, p=0.49) in hormone-receptor-positive cancers. Addition of LHRH agonists to tamoxifen, chemotherapy, or both reduced recurrence by 12.7% (2.4-21.9, p=0.02); and death after recurrence by 15.1% (1.8-26.7, p=0.03). LHRH agonists showed similar efficacy to chemotherapy (recurrence 3.9% increase, 7.7% reduction to 17.0% increase; death after recurrence 6.7% reduction, 20.7% reduction to 9.6% increase; both not significant). No trials had assessed an LHRH agonist versus chemotherapy with tamoxifen in both arms. LHRH agonists were ineffective in hormone-receptor-negative tumours.

INTERPRETATION

LHRH agonists provide an additional class of agents for treatment of premenopausal women with hormone-receptor-positive breast cancer. Optimum duration of use is unknown.

Alternating versus concurrent schedules of imatinib and chemotherapy as front-line therapy for Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL)

The best strategy for incorporating imatinib in front-line treatment of Ph+ acute lymphoblastic leukemia (ALL) has not been established. We enrolled 92 patients with newly diagnosed Ph+ ALL in a prospective, multicenter study to investigate sequentially 2 treatment schedules with imatinib administered concurrent to or alternating with a uniform induction and consolidation regimen. Coadministration of imatinib and induction cycle 2 (INDII) resulted in a complete remission (CR) rate of 95% and polymerase chain reaction (PCR) negativity for BCR-ABL in 52% of patients, compared with 19% in patients in the alternating treatment cohort (P = .01). Remarkably, patients with and without a CR after induction cycle 1 (INDI) had similar hematologic and molecular responses after concurrent imatinib and INDII. In the concurrent cohort, grades III and IV cytopenias and transient hepatotoxicity necessitated interruption of induction in 87% and 53% of patients, respectively; however, duration of induction was not prolonged when compared with patients receiving chemotherapy alone. No imatinib-related severe hematologic or nonhematologic toxicities were noted with the alternating schedule. In each cohort, 77% of patients underwent allogeneic stem cell transplantation (SCT) in first CR (CR1). Both schedules of imatinib have acceptable toxicity and facilitate SCT in CR1 in the majority of patients, but concurrent administration of imatinib and chemotherapy has greater antileukemic efficacy.

Therapeutic platelet transfusion versus routine prophylactic transfusion in patients with haematological malignancies: an open-label, multicentre, randomised study

BACKGROUND

Routine prophylactic platelet transfusion is the standard of care for patients with severe thrombocytopenia. We assessed the effect of a new strategy of therapeutic platelet transfusion on the number of transfusions and safety in patients with hypoproliferative thrombocytopenia.

METHODS

We did a multicentre, open-label, randomised parallel-group trial at eight haematology centres in Germany. Patients aged 16-80 years, who were undergoing intensive chemotherapy for acute myeloid leukaemia or autologous haemopoietic stem-cell transplantation for haematological cancers, were randomly assigned via a computer-generated randomisation sequence to receive either platelet transfusion when bleeding occurred (therapeutic strategy) or when morning platelet counts were 10×10(9) per L or lower (prophylactic strategy). Investigators undertaking interventions were not masked to group assignment. The primary endpoint was the number of platelet transfusions. Analysis was by intention to treat. This trial is registered, NCT00521664.

FINDINGS

197 patients were assigned the prophylactic strategy and 199 the therapeutic strategy. Of 391 patients analysed, the therapeutic strategy reduced the mean number of platelet transfusions by 33·5% (95% CI 22·2-43·1; p<0·0001) in all patients (2·44 [2·22-2·67] in prophylactic group vs 1·63 [1·42-1·83] in therapeutic group), 31·6% (18·6-42·6; p<0·0001) in those with acute myeloid leukaemia (2·68 [2·35-3·01] vs 1·83 [1·58-2·10]), and 34·2% (6·6-53·7; p=0·0193) in those who had had autologous transplantation (1·80 [1·45-2·15] vs 1·18 [0·82-1·55]. We noted no increased risk of major haemorrhage in patients who had undergone autologous transplantation. In those with acute myeloid leukaemia, risk of non-fatal grade 4 (mostly CNS) bleeding was increased. We recorded 15 cases of non-fatal haemorrhage: four retinal in each transfusion group, and one vaginal and six cerebral in the therapeutic group. 12 patients died in the study: two from fatal cerebral haemorrhages in the therapeutic group, and ten (five in each treatment group) unrelated to major bleeding.

INTERPRETATION

The therapeutic strategy could become a new standard of care after autologous stem-cell transplantation; however, prophylactic platelet transfusion should remain the standard for patients with acute myeloid leukaemia. The new strategy should be used by some haematology centres only if the staff are well educated and experienced in the new approach and can react in a timely way to first signs of CNS bleeding.

FUNDING

Deutsche Krebshilfe eV (German Cancer Aid).

Characterization of breast carcinomas by two monoclonal antibodies distinguishing myoepithelial from luminal epithelial cells

Two monoclonal antibodies, KA 1 and KA 4, raised against human epidermis, were biochemically and immunologically characterized and were shown to react with specific cytokeratin polypeptides. On frozen sections of human mammary gland, these antibodies distinguish between myoepithelial and luminal epithelial cells. We present evidence that in these cells KA 1 antibody recognized cytokeratin 5 and KA 4 antibody cytokeratin 19. In normal mammary tissue, KA 4 antibody invariably reacted with the epithelial cells lining the lumina of acini, ductules, ducts, and sinus. In contrast, KA 1 antibody decorated only the myoepithelial and basal epithelial cells of acini, ducts, and sinus. In ductules, however, KA 1 also stained the luminal cells. All 73 invasive lobular and ductal carcinomas studied reacted with KA 4 antibody; five of these were also positive, apparently in the same tumor cells, with KA 1. The tumor cells of in situ carcinomas were also stained in a homogeneous pattern with KA 4 antibody; KA 1 antibody reacted only with the surrounding myoepithelium. In epithelial hyperplasias, the proliferating cells were decorated by KA 1 and KA 4 antibodies in a heterogeneous pattern. Other antibodies were used for comparison. The results are discussed with respect to epithelial differentiation and pathogenesis and to the application of such antibodies for immunohistodiagnosis of mammary lesions.

Detection of tumor cells in bone marrow of patients with primary breast cancer: a prognostic factor for distant metastasis

PURPOSE

At the time of primary surgery, approximately 90% of all patients with breast cancer are free of metastases, but in the next 5 years almost 50% of them will relapse. We evaluated the significance of the presence of tumor cells in bone marrow of patients with primary breast cancer to investigate their predictive value for relapse.

PATIENTS AND METHODS

Two hundred sixty patients with primary breast cancer were examined for tumor cells in bone marrow aspirates taken from six sites of the skeleton. After density centrifugation, cells in interphase were smeared and stained. For the immunocytologic reaction, we used a new monoclonal antibody (2E11) that was reactive with the core protein of the tumor-associated glycoprotein TAG12. TAG12 is secreted by nearly all human breast carcinomas.

RESULTS

A significant correlation was found between tumor-cell detection and tumor stage (P < .0001), nodal status (P < .0001), and tumor grading (P = .002). A good relation to progesterone receptor (PR; P = .008) was found, but there was no correlation to estrogen receptor (ER) and menopausal status. Follow-up examinations showed distant metastases in 26 of 211 patients (15%). Twenty-two relapses occurred among the 81 patients with 2E11-positive cells in bone marrow, but only four occurred among the 130 patients without tumor-cell detection.

CONCLUSIONS

This study suggests that tumor-cell detection in bone marrow of patients with primary breast carcinoma is a good predictor for all distant relapses (P < .0005, Cox multiple regression analysis) and provides additional information in regard to other prognostic factors. The highest predicting value for distant metastasis results from the combination of nodal status, negative PR, and tumor-cell presence in bone marrow.

Multicenter phase II study of oral capecitabine (Xeloda(")) in patients with metastatic breast cancer relapsing after treatment with a taxane-containing therapy

BACKGROUND

Capecitabine is a rationally designed oral, tumor-activated fluoropyrimidine carbamate with high activity in metastatic breast cancer. This multicenter phase II study was designed to evaluate further the efficacy and safety of capecitabine in patients with metastatic breast cancer previously treated with a taxane-containing regimen.

PATIENTS AND METHODS

All patients had to have documented progression after paclitaxel- or docetaxel-containing chemotherapy. Treatment comprised 3-week cycles of oral capecitabine 1250 mg/m(2) twice-daily for 14 days followed by a 7-day rest period.

RESULTS

One hundred and thirty-six patients were enrolled. Disease stabilization occurred in 63 patients (46%) and the overall response rate was 15% (95% confidence interval 10% to 23%), providing an overall tumor control rate of 62%. Median time to progression was 3.5 months, median duration of response was 7.5 months and median overall survival was 10.1 months. Capecitabine was generally well-tolerated: most treatment-related adverse events were grade 1/2 in intensity; grade 3/4 treatment-related adverse events were hand-foot syndrome (13%), diarrhea (8%), vomiting (4%) and nausea (3%). There were no treatment-related deaths.

CONCLUSIONS

This study confirms that capecitabine achieves a high tumor control rate in heavily pretreated patients with metastatic breast cancer. Due to its favorable safety profile and convenient oral administration, capecitabine can be given as an outpatient therapy. Capecitabine should be considered the reference treatment in this setting based on consistently high efficacy and good tolerability.

Augmentation of mechanical properties in osteoporotic vertebral bones--a biomechanical investigation of vertebroplasty efficacy with different bone cements

Recent clinical trials have reported favorable early results for transpedicular vertebral cement reinforcement of osteoporotic vertebral insufficiencies. There is, however, a lack of basic data on the application, safety and biomechanical efficacy of materials such as polymethyl-methacrylate (PMMA) and calciumphospate (CaP) cements. The present study analyzed 33 vertebral pairs from five human cadaver spines. Thirty-nine vertebrae were osteoporotic (bone mineral density < 0.75 g/cm2), 27 showed nearly normal values. The cranial vertebra of each pair was augmented with either PMMA (Palacos E-Flow) or experimental brushite cement (EBC), with the caudal vertebra as a control. PMMA and EBC were easy to inject, and vertebral fillings of 20-50% were achieved. The maximal possible filling was inversely correlated to the bone mineral density (BMD) values. Cement extrusion into the spinal canal was observed in 12% of cases. All specimens were subjected to axial compression tests in a displacement-controlled mode. From load-displacement curves, the stiffness, S, and the maximal force before failure, Fmax, were determined. Compared with the native control vertebrae, a statistically significant increase in vertebral stiffness and Fmax was observed by the augmentation. With PMMA the stiffness increased by 174% (P = 0.018) and Fmax by 195% (P = 0.001); the corresponding augmentation with EBC was 120% (P = 0.03) and 113% (P = 0.002). The lower the initial BMD, the more pronounced was the augmentation effect. Both PMMA and EBC augmentation reliably and significantly raised the stiffness and maximal tolerable force until failure in osteoporotic vertebral bodies. In non-porotic specimens, no significant increase was achieved.

Beta-galactoside-binding protein secreted by activated T cells inhibits antigen-induced proliferation of T cells

We have used mRNA differential display PCR to search for genes induced in activated T cells and have found the LGALS1 (lectin, galactoside-binding, soluble) gene to be strongly up-regulated in effector T cells. The protein coded by the LGALS1 gene is a beta-galactoside-binding protein (betaGBP), which is released by cells as a monomeric negative growth factor but which can also associate into homodimers (galectin-1) with lectin properties. Northern blot analysis revealed that ex vivo isolated CD8+ effector T cells induced by a viral infection expressed high amounts of LGALS1 mRNA, whereas LGALS1 expression was almost absent in resting CD8+ T cells. LGALS1 expression could be induced in CD4+ and CD8+ T cells upon activation with the cognate peptide antigen and high levels of LGALS1 expression were found in concanavalin A-activated T cells but not in lipopolysaccharide-activated B cells. Gel filtration and Western blot analysis revealed that only monomeric betaGBP was released by activated CD8+ T cells and in vitro experiments further showed that recombinant betaGBP was able to inhibit antigen-induced proliferation of naive and antigen-experienced CD8+ T cells. Thus, these data indicate a role of betaGBP as an autocrine negative growth factor for CD8+ T cells.

Autosomal-Recessive Mutations in SLC34A1 Encoding Sodium-Phosphate Cotransporter 2A Cause Idiopathic Infantile Hypercalcemia

Idiopathic infantile hypercalcemia (IIH) is characterized by severe hypercalcemia with failure to thrive, vomiting, dehydration, and nephrocalcinosis. Recently, mutations in the vitamin D catabolizing enzyme 25-hydroxyvitamin D3-24-hydroxylase (CYP24A1) were described that lead to increased sensitivity to vitamin D due to accumulation of the active metabolite 1,25-(OH)2D3. In a subgroup of patients who presented in early infancy with renal phosphate wasting and symptomatic hypercalcemia, mutations in CYP24A1 were excluded. Four patients from families with parental consanguinity were subjected to homozygosity mapping that identified a second IIH gene locus on chromosome 5q35 with a maximum logarithm of odds (LOD) score of 6.79. The sequence analysis of the most promising candidate gene, SLC34A1 encoding renal sodium-phosphate cotransporter 2A (NaPi-IIa), revealed autosomal-recessive mutations in the four index cases and in 12 patients with sporadic IIH. Functional studies of mutant NaPi-IIa in Xenopus oocytes and opossum kidney (OK) cells demonstrated disturbed trafficking to the plasma membrane and loss of phosphate transport activity. Analysis of calcium and phosphate metabolism in Slc34a1-knockout mice highlighted the effect of phosphate depletion and fibroblast growth factor-23 suppression on the development of the IIH phenotype. The human and mice data together demonstrate that primary renal phosphate wasting caused by defective NaPi-IIa function induces inappropriate production of 1,25-(OH)2D3 with subsequent symptomatic hypercalcemia. Clinical and laboratory findings persist despite cessation of vitamin D prophylaxis but rapidly respond to phosphate supplementation. Therefore, early differentiation between SLC34A1 (NaPi-IIa) and CYP24A1 (24-hydroxylase) defects appears critical for targeted therapy in patients with IIH.

In vivo chemosensitivity-adapted preoperative chemotherapy in patients with early-stage breast cancer: the GEPARTRIO pilot study

BACKGROUND

Response to the first two cycles of preoperative chemotherapy might differentiate subgroups of breast cancer patients with high or minimal chances for a pathologic complete response (pCR) and may be used as an in vivo chemosensitivity test.

METHODS

Breast cancer patients were treated with two cycles of TAC (docetaxel 75 mg/m(2), doxorubicin 50 mg/m(2), cyclophosphamide 500 mg/m(2) every 21 days). Patients whose tumors showed a response received four more cycles. Patients whose tumors did not respond were randomized to four additional cycles TAC or NX (vinorelbine 25 mg/m(2) days 1 and 8, capecitabine 2000 mg/m(2) days 1-14, every 21 days). The primary end point was pCR at surgery.

RESULTS

Two hundred and eighty-five patients showed a clinical response, in 73.0% after two cycles, in 88.4% at surgery, and a pCR was seen in 17.9%. Breast conservation was possible in 72.2%. Responding patients obtained a pCR in 22.6% whereas non-responding patients reached a pCR in 7.3% and 3.1% with TAC or NX, respectively. Grade III/IV neutropenia and febrile neutropenia were observed during TAC in 70.2% and 13.5%, respectively. Significantly less toxicity were observed with NX.

CONCLUSION

Early response to TAC can reliably identify patients with a high chance of achieving a pCR. New effective treatments need to be explored for patients without an early response.

Clinical utility of simultaneous quantitation of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D by LC-MS/MS involving derivatization with DMEQ-TAD

CONTEXT

The discovery of hypercalcemic diseases due to loss-of-function mutations in 25-hydroxyvitamin D-24-hydroxylase has placed a new demand for sensitive and precise assays for 24,25-dihydroxyvitamin D [24,25-(OH)2D].

OBJECTIVE

We describe a novel liquid chromatography and tandem mass spectrometry-based method involving derivatization with DMEQ-TAD {4-[2-(6,7-dimethoxy-4-methyl-3,4-dihydroquinoxalinyl)ethyl]-1,2,4-triazoline-3,5-dione} to simultaneously assay multiple vitamin D metabolites including 25-hydroxyvitamin D (25-OH-D) and 24,25-(OH)2D using 100 μL of serum with a 5-minute run time.

DESIGN

The assay uses a newly synthesized internal standard d6-24,25-(OH)2D3 enabling the quantitation of 24,25-(OH)2D3 as well as the determination of the ratio of 25-OH-D3 to 24,25-(OH)2D3, a physiologically useful parameter.

SETTING

We report data on more than 1000 normal and disease samples involving vitamin D deficiency or hypercalcemia in addition to studies involving knockout mouse models.

RESULTS

The assay showed good correlation with samples from quality assurance schemes for 25-OH-D (25-OH-D2 and 25-OH-D3) determination (-2% to -5% bias) and exhibited low inter- and intraassay coefficients of variation (4%-7%) and lower limits of quantitation of 0.25-0.45 nmol/L. In clinical studies, we found a strong correlation between serum levels of 25-OH-D3 and 24,25-(OH)2D3 (r(2) = 0.80) in subjects over a broad range of 25-OH-D3 values and a marked lack of production of 24,25-(OH)2D3 below 25 nmol/L of 25-OH-D. The ratio of 25-OH-D3 to 24,25-(OH)2D3, which remained less than 25 in vitamin D-sufficient subjects (serum 25-OH-D < 50 nmol/L) but was greatly elevated (80-100) in patients with idiopathic infantile hypercalcemia.

CONCLUSIONS

The new method showed good utility in clinical settings involving vitamin D deficiency; supplementation with vitamin D and idiopathic infantile hypercalcemia, as well as in animal models with ablation of selected cytochrome P450-containing enzymes involved in vitamin D metabolism.

Monoclonal immunoglobulin A antibody directed against serotype-specific epitope of Shigella flexneri lipopolysaccharide protects against murine experimental shigellosis

To determine the role of humoral mucosal immune response in protection against shigellosis, we have obtained a monoclonal dimeric immunoglobulin A (IgA) antibody specific for Shigella flexneri serotype 5a lipopolysaccharide (mIgA) and used a murine pulmonary infection model that mimics the lesions occurring in natural intestinal infection. Adult BALB/c mice challenged with 10(7) S. flexneri organisms developed a rapid inflammatory response characterized by polymorphonuclear cell infiltration around and within the bronchi and strong systemic interleukin 6 response. Implantation of hybridoma cells in the back of mice, resulting in the development of a myeloma tumor producing mIgA in the serum and subsequently secretory mIgA in local secretions, or direct intranasal administration of these antibodies, protected the animals against subsequent intranasal challenge with S. flexneri serotype 5a. Absence of histopathological lesion and significant decrease in bacterial load of the lungs and of systemic interleukin 6 response were the three major criteria of protection. This protection was shown to be serotype-specific and dependent on local concentration of mIgA. These data demonstrate that mucosal antibodies directed against a single polysaccharidic surface epitope of Shigella can protect against the disease.

Dose-dense doxorubicin, docetaxel, and granulocyte colony-stimulating factor support with or without tamoxifen as preoperative therapy in patients with operable carcinoma of the breast: a randomized, controlled, open phase IIb study

PURPOSE

To investigate the effect of adding tamoxifen to a preoperative dose-dense doxorubicin and docetaxel regimen on the pathologic response of primary operable breast cancer.

PATIENTS AND METHODS

Patients (tumor size > or = 3 cm, N0 to 2, M0) were prospectively randomized to receive every 14 days a total of four cycles of doxorubicin 50 mg/m2 and docetaxel 75 mg/m(2), either with (ADocT) or without (ADoc) simultaneous tamoxifen. Granulocyte colony-stimulating factor (G-CSF) was routinely given on days 5 to 10. Surgery followed 8 to 10 weeks after the start of treatment.

RESULTS

Within 14 months, 250 patients were included in the study at 56 centers. Of 992 planned cycles, 97.9% were administered. Pathologically complete remission (pCR) with no detectable viable tumor cells was achieved in 9.7%. There was a nonsignificant difference of -1.2% in favor of ADoc, with a 95% confidence interval of -8.6% to 6.2%. A further 2.4% had only noninvasive tumor residues, and 13.8% had focal invasive residues. Complete and partial responses detected by palpation were observed in 28.9% and 52.4%, respectively. The response rates (complete and partial) by best appropriate imaging methods were 77.5% and 67.5% for ADocT and ADoc, respectively. Breast conservation was possible in 68.8% of the patients. A tendency toward more frequent toxic events was observed with ADocT treatment. Significant predictors of pCR to chemotherapy were negative lymph node and negative estrogen receptor status.

CONCLUSION

A dose-dense regimen of ADoc with G-CSF offers high compliance, moderate toxicity, and rapid efficacy as a form of preoperative chemotherapy in operable breast cancer. Concurrent treatment with tamoxifen for 8 weeks could not improve the pathologic response rate.

Comparison of immunohistochemistry and RT-PCR for detection of CD44v-expression, a new prognostic factor in human breast cancer

In different human tumors, splice variants of the surface glycoprotein CD44 (CD44v) are correlated with advanced stages of tumor growth and metastatic potential. In breast cancer and colon cancer, expression of epitopes encoded by exon v6 on primary tumors is an independent prognostic factor for poor patient survival. Two different screening methods for the detection of CD44 variants in tumors have been applied: immunohistochemistry (IHC) and semi-quantitative reverse transcription PCR (RT-PCR). In this study, we have compared the predictive capacity and the applicability of both approaches, using 31 human breast-tissue specimens (normal and neoplastic). IHC reveals lack of expression of CD44v on normal ductal epithelial cells but strong expression on myoepithelial cells. The majority of tumors express CD44 epitopes encoded by several variant exons. RT-PCR detects splice variants in normal epithelium, probably derived from RNA expressed in the myoepithelium. In tumors, RT-PCR reveals expression of a wide range of splice variants, including new ones that are not detected in normal breast tissue, e.g. ones that contain all variant exons. The conclusion of this comparison is that IHC is the better method for breast-tumor sample screening but that the increased sensitivity of RT-PCR can help to distinguish CD44v-positive from CD44v-negative tumors in cases where only a few tumor cells express variants or where epitopes are masked.