Biomedical subjects

Rafael Fonseca

Publications and source records attributed to Rafael Fonseca.

At least 37 records · Page 2Linked to original sources

PubMed2005

A validated FISH trisomy index demonstrates the hyperdiploid and nonhyperdiploid dichotomy in MGUS.

Two major genetic categories of multiple myeloma (MM) exist. Hyperdiploid MM (48 to 74 chromosomes, median 53 chromosomes) is associated with trisomies especially of chromosomes 3, 7, 9, 11, 15, and 19, whereas the nonhyperdiploid (< 48 chromosomes or more than 74 chromosomes) MM is associated with primary translocations such as t(11;14), t(4;14), and t(14;16). Whether this dichotomy exists in monoclonal gammopathy of undetermined significance (MGUS) is uncertain due to limitations of current methods in the study of ploidy. This is especially true in MGUS where the number of clonal plasma cells is small. In this study, we derived a fluorescent in situ hybridization (FISH)-based trisomy index from pooled cytogenetic data (karyotype analysis) from 2 large cohorts of patients with MM with abnormal karyotype, and then validated it in 2 independent cohorts of patients who had known ploidy status either by karyotyping or DNA content measurement using flow cytometry. Using the criteria of 2 or more trisomies from a 3-chromosome combination, hyperdiploid myeloma can be detected with high specificity. Applying this index on 28 patients with smoldering multiple myeloma (SMM) or MGUS (11 SMM, 17 MGUS) who had normal karyotype, 11 cases of hyperdiploid SMM/MGUS were detected. This percentage (40%) is remarkably similar to the percentage of hyperdiploid MM reported in the literature, suggesting that hyperdiploid MM may originate early during disease evolution.

Cohort Studies↗

PubMed2005

Primary plasma cell leukemia: report of 17 new cases treated with autologous or allogeneic stem-cell transplantation and review of the literature.

Primary plasma cell leukemia (PPCL) is a rare hematologic malignancy characterized by the proliferation of plasma cells in blood, bone marrow, and other organs in the absence of established multiple myeloma. PPCL has a poor prognosis when treated with conventional therapy for multiple myeloma. We describe here 17 new cases of PPCL who underwent stem-cell transplantation (SCT) (2 cases observed by the authors and 15 cases from the International Bone Marrow Transplant Registry [IBMTR]). The first case was diagnosed in a 21-year-old male who presented with leukocytosis and acute renal failure. He was treated with hyper-CVAD, entered complete remission, and then proceeded to high-dose chemotherapy with peripheral stem-cell support. He is currently in complete remission 23 months after initial diagnosis and 19 months after autologous SCT. The second case was observed in a 31-year-old male who presented with leukocytosis and hepatic infiltration with plasma cells. He was treated with VAD chemotherapy and underwent allogeneic bone marrow transplantation from his HLA-identical sister. He remained in complete remission for 3 years and then developed progressive refractory disease, dying 7 years after the initial diagnosis. In addition to these 2 cases, 15 further unpublished cases of PPCL from the IBMTR are reported here (treated between 1993 and 2001, 6 by autologous and 9 by allogeneic transplantation). Finally, the features of PPCL, the outcome, published data of SCT for PPCL, and indications for treatment are discussed.

Adult↗

PubMed2005

Genetics of multiple myeloma.

In recent years, we have seen an explosion in knowledge of the genetics and cytogenetics of the plasma-cell neoplasms. This chapter will deal with these advances and will place them in the integrative context of the pathophysiologic basis of the disease, and will discuss the important clinical implications of these abnormalities. We have learned that myeloma can be classified into increasingly definable subgroups that follow a basic global hierarchical grouping. All gene expression profiling strategies have come to similar conclusions and confirm the subgroups previously identified by karyotype, molecular cytogenetics and other genetic studies. At the top level there are two major pathogenetic pathways for the development of plasma cell tumors: one that is associated with hyperdiploidy and one that is characterized by the presence of chromosome translocations involving the immunoglobulin heavy chain locus (IgH). These translocations are seen in up to 60% of patients, but involve a common recurrent chromosome partner in only 40-50% of patients. Several genetic markers are now shown to be associated with a shortened survival. Of these, the most common ones include abnormalities (deletion and monosomy) of chromosome 13, the global state of hypodiploidy and abnormalities of chromosome 1. Many of the translocations observed in MM are also seen in monoclonal gammopathy of undetermined significance (MGUS), even in individuals without progression to full malignant disease for many years. The identification of critical genetic lesions will pave the way for the development of disease-targeted therapy.

Chromosome Aberrations↗

PubMed2005

Ectopic expression of VAV1 reveals an unexpected role in pancreatic cancer tumorigenesis.

Herein, we show that the hematopoietic-specific GEF VAV1 is ectopically expressed in primary pancreatic adenocarcinomas due to demethylation of the gene promoter. Interestingly, VAV1-positive tumors had a worse survival rate compared to VAV1-negative tumors. Surprisingly, even in the presence of oncogenic KRAS, VAV1 RNAi abrogates neoplastic cellular proliferation in vitro and in vivo, thus identifying Vav1 as a growth-stimulatory protein in this disease. Vav1 acts synergistically with the EGF receptor to stimulate pancreatic tumor cell proliferation. Mechanistically, the effects of Vav1 require its GEF activity and the activation of Rac1, PAK1, and NF-kappaB and involve cyclin D1 upregulation. Thus, the discovery of prooncogenic pathways regulated by Vav1 makes it an attractive target for therapeutic intervention.

Adenocarcinoma↗

PubMed2005

Detection of chromosome 13 deletions by fluorescent in situ hybridization.

Multiple myeloma (MM), like other hematological malignancies, has both normal and clonal neoplastic cells coresiding in the bone marrow. To perform interphase fluorescent in situ hybridization (FISH) analysis accurately, for the detection of clonal chromosome abnormalities, it is crucial to restrict the analysis to the tumoral cells. The correct detection of these abnormalities may have diagnostic, prognostic, and therapeutic implications. Our laboratory has developed a clone-specific cytoplasmic immunoglobulin (cIg) staining method coupled with FISH (cIg-FISH) for the study of plasma cell (PC) neoplasms. An unlimited combination of DNA probes can be used with this technique to examine the genetic changes that frequently occur in patients with these diseases, one of which is abnormalities of chromosome 13. Using the two techniques simultaneously (i.e., cIg-FISH), we have demonstrated that approx 50% of patients with MM have abnormalities of chromosome 13, mostly monosomy, and when present involving the majority of the cells. In this chapter, we present the technical methodology for detecting chromosome abnormalities and how to restrict the analysis to the clonal PCs.

Cell Culture Techniques↗

PubMed2005

Genomics in multiple myeloma: biology and clinical implications.

The advent of new techniques, such as interphase fluorescence in situ hybridization, and, more recently, global array-based gene expression profiling, has accelerated genomic research in myeloma. Distinct biologic subtypes, characterized by unique genetic abnormalities with differing clinical outcomes, have been identified. The identification of these primary genetic defects, and the deregulated oncogenes and pathways in myeloma, has allowed for the development of more targeted therapies. This has led to the discovery of an increased number of active agents in the treatment of myeloma. Genetics also have prognostic importance in myeloma. Recent studies have elucidated a genetic prognostic hierarchy, and have enabled improved definition of the prognostic significance of their interactions. The current challenges are to: improve the dissection of the genetic heterogeneity of the disease; better define progression events; improve the risk stratification of patients; more accurately select patients who will respond well to a particular treatment; and develop more rational combinations of treatment. Genomics will have an important role to play in all of these goals.

Disease Progression↗

PubMed2005

Risk stratification of patients with newly diagnosed multiple myeloma: optimizing treatment based on pretreatment characteristics.

Marked clinical and biologic heterogeneity exists in multiple myeloma (MM). Over the years, many prognostic factors have been identified and several prognostic systems have been proposed. The integration of data from international groups including patients treated with common modalities such as chemotherapy and high-dose therapy culminated in the International Staging System. Recently, genetic information has also been shown to include powerful prognostic factors across different treatment modalities. These advances have facilitated categorization of patients into different risk groups, particularly a subset of patients at high risk with short survival times after current standard therapy. The expanding armamentarium of effective treatments in MM also means that it is now possible to select treatments for patients based on their risk categories. This review will summarize the important prognostic factors identified to date, how they can be used to identify patients at high risk, and their clinical utility in relation to treatment optimization at diagnosis.

Humans↗

PubMed2005

Combination therapy with thalidomide and dexamethasone in patients with newly diagnosed multiple myeloma not undergoing upfront autologous stem cell transplantation: a phase II trial.

BACKGROUND AND OBJECTIVES: Thalidomide plus dexamethasone (Thal/Dex) has emerged as an effective alternative to vincristine, doxorubicin and dexamethasone as a pre-transplant induction therapy for newly diagnosed multiple myeloma. However, many patients treated initially with Thal/Dex do not proceed to autologous stem cell transplantation (ASCT) and the time to progression and other outcome measures with Thal/Dex as primary therapy for multiple myeloma are not known. We present the first data on the outcome of patients with newly diagnosed multiple myeloma treated with Thal/Dex who did not undergo upfront ASCT. DESIGN AND METHODS: We identified 21 patients with newly diagnosed multiple myeloma treated with Thal/Dex on a phase II clinical trial who did not undergo ASCT due to age, comorbidity or the patient's refusal. Patients received thalidomide at a dose of 200 mg/day orally and dexamethasone 40 mg daily on days 1-4, 9-12, 17-20 (odd months) and days 1-4 (even months). Cycles were repeated every 28 days. RESULTS: The median age was 66 years (range 36-78). The median duration of follow-up was 21 months (range 1-52). One (5%) patient achieved a complete response, and 9 (43%) had a partial response, so the overall response rate was 48%. Of the remaining patients, 7 (33.3%) had stable disease, one patient did not respond, and three died while on therapy prior to response assessment. The median overall survival and time to progression were 21 months and 18 months, respectively. INTERPRETATION AND CONCLUSIONS: The median time to disease progression in patients with multiple myeloma who receive initial therapy with Thal/Dex and who do not undergo ASCT is 18 months.

Adult↗

PubMed2004

Initial immunoglobulin M 'flare' after rituximab therapy in patients diagnosed with Waldenstrom macroglobulinemia: an Eastern Cooperative Oncology Group Study.

BACKGROUND: The goal of the current study was to characterize the initial upsurge in immunoglobulin M (IgM) levels after treatment with rituximab in patients with Waldenstrom macroglobulinemia (WM). METHODS: As part of a Phase II Eastern Cooperative Oncology Group study, 72 patients were treated with rituximab (375 mg/m(2) weekly for 4 weeks) between April 2000 and January 2002. IgM levels in these patients were measured at five separate time points so that any temporal changes that occurred could be characterized. RESULTS: Of the 54 patients for whom the relevant IgM measurements were available, 29 (54%) experienced an increase in IgM levels between baseline and the first scheduled postbaseline time point. At 2 months, 13 of 22 evaluable patients (59%) continued to have elevated IgM levels, and at 4 months, elevated IgM levels persisted in 4 of 15 evaluable patients (27%). Overall, a nonlinear trend characterized by an initial increase in IgM levels followed by a decrease in these levels was observed (P < 0.0001). CONCLUSIONS: Treating physicians should be aware that an IgM 'flare' may occur in up to 54% of patients treated with rituximab; however, most of these patients experience a decrease in IgM levels within 4 months after the initiation of therapy. Therefore, patients should not be discouraged from continuing to receive this potentially effective therapeutic agent, as responses to rituximab may develop slowly. Longer follow-up will reveal whether patients who experience an upsurge in IgM levels have poorer overall survival or shorter times to progression compared with patients who do not experience this IgM flare. Factors predicting an initial increase in IgM levels could not be identified.

Adult↗

PubMed2004

Functional gene expression analysis of clonal plasma cells identifies a unique molecular profile for light chain amyloidosis.

Immunoglobulin light chain amyloidosis (AL) is characterized by a clonal expansion of plasma cells within the bone marrow. Gene expression analysis was used to identify a unique molecular profile for AL using enriched plasma cells (CD138+) from the bone marrow of 24 patients with AL and 28 patients with multiple myeloma (MM) and 6 healthy controls. Class prediction analysis (PAM) revealed a subset of 12 genes, which included TNFRSF7 (CD27), SDF-1, and PSMA2, that distinguished between these 2 groups with an estimated and observed accuracy of classification of 92%. This model was validated with an independent dataset of 11 patients with AL and 12 patients with MM with 87% accuracy. Differential expression for the most discriminant genes in the 12-gene subset was validated using quantitative real-time polymerase chain reaction and protein expression analysis, which upheld the observations from the micro-array expression data. Functional analyses using a novel network mapping software revealed a number of potentially significant pathways that were dysregulated in patients with AL, with those regulating proliferation, apoptosis, cell signaling, chemotaxis, and migration being substantially represented. This study provides new insight into the molecular profile of clonal plasma cells and its functional relevance in the pathogenesis of light chain amyloidosis.

Aged↗

PubMed2004

Serum cardiac troponins and N-terminal pro-brain natriuretic peptide: a staging system for primary systemic amyloidosis.

PURPOSE: Primary systemic amyloidosis (AL) is a multisystemic disorder resulting from an underlying plasma cell dyscrasia. There is no formal staging system for AL, making comparisons between studies and treatment centers difficult. Our group previously identified elevated serum cardiac troponin T (cTnT) as the most powerful predictor of overall survival. Others have reported that N-terminal pro-brain natriuretic peptide (NT-proBNP) is a valuable prognostic marker. We sought to develop a staging system for patients with AL. PATIENTS AND METHODS: Two hundred forty-two patients with newly diagnosed AL who were seen at the Mayo Clinic between April 1979 and November 2000, and who had echocardiograms and stored serum samples at presentation were eligible for this retrospective review. NT-proBNP measurements were performed on 242 patients in whom cTnT and cardiac troponin I (cTnI) had been previously run. Two prognostic models were designed using threshold values of NT-proBNP and either cTnT or cTnI (NT-proBNP < 332 ng/L, cTnT < 0.035 microg/L, and cTnI < 0.1 microg/L). Depending on whether NT-proBNP and troponin levels were both low, were high for only one level, or were both high, patients were classified as stage I, II, or III, respectively. RESULTS: Using the cTnT+NT-proBNP model 33%, 30%, and 37% of patients were stages I, II, and III, respectively, with median survivals of 26.4, 10.5, and 3.5 months, respectively. The alternate cTnI+NT-proBNP model predicted median survivals of 27.2, 11.1, and 4.1 months, respectively. CONCLUSION: Stratification of AL patients into three stages is possible with two readily available and reproducible tests setting the stage for more consistent and reliable cross comparisons of therapeutic outcomes.

Adult↗

PubMed2004

Prognostication of survival using cardiac troponins and N-terminal pro-brain natriuretic peptide in patients with primary systemic amyloidosis undergoing peripheral blood stem cell transplantation.

Primary systemic amyloidosis (AL) is a fatal plasma cell disorder. Pilot data suggest survival is better in patients undergoing peripheral blood stem cell transplantation (PBSCT), but the selection process makes the apparent benefit suspect. We have reported that circulating cardiac biomarkers are the best predictors of survival outside of the transplantation setting. We now test whether cardiac troponins (cTnT and cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are prognostic in transplant recipients. In 98 patients with AL undergoing PBSCT, serum cardiac biomarkers were measured (cTnT, 98 patients; cTnI, 65 patients; and NT-proBNP, 63 patients). Elevated levels of cTnT, cTnI, and NT-proBNP were present in 14%, 43%, and 48% of patients, respectively. At 20 months median follow-up, median survival has not been reached for patients with values below the thresholds; in patients with values above the thresholds, median survival is 26.1 months, 66.1 months, and 66.1 months, respectively. Our previously reported risk systems incorporating these markers were also prognostic, notably the cTnT/NT-proBNP staging. Using this system, 49%, 38%, and 13% of patients were in stage I, stage II, and stage III, respectively. Determining levels of circulating biomarkers may be the most powerful tool for staging patients with AL undergoing PBSCT.

Adult↗

PubMed2004

Acquired Fanconi syndrome is an indolent disorder in the absence of overt multiple myeloma.

Adult-acquired Fanconi syndrome (FS) is a rare complication of monoclonal gammopathy. We retrospectively reviewed 32 patients diagnosed with adult-acquired FS between April 1968 and June 2002 at Mayo Clinic (Rochester, MN). At diagnosis, most patients had monoclonal gammopathy of undetermined significance (MGUS) or smoldering multiple myeloma (SMM), with a median creatinine level of 176.8 microM (2.0 mg/dL; range, 79.56-327.08 microM [0.9-3.7 mg/dL]) and evidence of osteomalacia. During the average 65 months (range, 2-238 months) of follow-up, 5 patients developed end-stage renal disease (ESRD) and only 1 of 14 patients with MGUS transformed to multiple myeloma (MM). Also, 14 deaths occurred, with only 1 from ESRD but 4 from alkylator-related leukemia or myelodysplastic syndrome. Chemotherapy offered little benefit on renal functions of MGUS or SMM patients. In conclusion, FS associated with monoclonal gammopathy does not appear to confer an additional risk of subsequent evolution to MM. ESRD occurs late in the disease process.

Adult↗

PubMed2004

Genetics and cytogenetics of multiple myeloma: a workshop report.

Much has been learned regarding the biology and clinical implications of genetic abnormalities in multiple myeloma. Because of recent advances in the field, an International Workshop was held in Paris in february of 2003. This summary describes the consensus recommendations arising from that meeting with special emphasis on novel genetic observations. For instance, it is increasingly clear that translocations involving the immunoglobin heavy-chain locus are important for the pathogenesis of one-half of patients. As a corollary, it also clear that the remaining patients, lacking IgH translocations, have hyperdiploidy as the hallmark of their disease. Several important genetic markers are associated with a shortened survival such as chromosome 13 monosomy, hypodiploidy, and others. The events leading the transformation of the monoclonal gammopathy of undetermined significance (MGUS) to myeloma are still unclear. One of the few differential genetic lesions between myeloma and MGUS is the presence of ras mutations in the latter. Gene expression platforms are capable of detecting many of the genetic aberrations found in the clonal cells of myeloma. Areas in need of further study were identified. The study of the genetic aberrations will likely form the platform for targeted therapy for the disease.

Aneuploidy↗

PubMed2004

Superior survival in primary systemic amyloidosis patients undergoing peripheral blood stem cell transplantation: a case-control study.

Primary systemic amyloidosis (AL) is a plasma cell dyscrasia resulting in multisystem failure and death. High-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) has been associated with higher response rates and seemingly higher overall survival than standard chemotherapy. Selection bias, however, confounds interpretation of these results. We performed a case-match-control study comparing overall survival of 63 AL patients undergoing transplantation with 63 patients not undergoing transplantation. Matching criteria included age, sex, time to presentation, left ventricular ejection fraction, serum creatinine, septal thickness, nerve involvement, 24-hour urine protein, and serum alkaline phosphatase. According to design, there was no difference between the groups with respect to sex (57% males), age (median, 53 years), left ventricular ejection fraction (65%), number of patients with peripheral nerve involvement (17%), cardiac interventricular septal wall thickness (12 mm), serum creatinine (1.1 mg/dL [97.24 micromol/L]), and bone marrow plasmacytosis (8%). Sixty-six patients have died (16 cases and 50 controls). For PBSCT and control groups, respectively, the 1-, 2-, and 4-year overall survival rates are 89% and 71%; 81% and 55%; and 71% and 41%. Outside a randomized clinical trial, these results present the strongest data supporting the role of PBSCT in selected patients with AL.

Adult↗

PubMed2004

Farnesyltransferase inhibitor tipifarnib is well tolerated, induces stabilization of disease, and inhibits farnesylation and oncogenic/tumor survival pathways in patients with advanced multiple myeloma.

Patients with multiple myeloma (MM) with mutated RAS are less likely to respond to chemotherapy and have a shortened survival. Therefore, targeting RAS farnesylation may be a novel approach to treatment of MM. We evaluated the activity and tolerability of the farnesyltransferase (FTase) inhibitor tipifarnib (Zarnestra) in a phase 2 trial as well as its ability to inhibit protein farnesylation and oncogenic pathways in patients with relapsed MM. Forty-three patients (median age, 62 years [range, 33-82 years]) with a median of 4 (range, 1-6) chemotherapy regimens entered the study. Tipifarnib, 300 mg orally twice daily, was administered for 3 weeks every 4 weeks. The most common toxicity was fatigue occurring in 66% of patients. Other toxicities included diarrhea, nausea, neuropathy, anemia, and thrombocytopenia. Sixty-four percent of the patients had disease stabilization. Treatment with tipifarnib suppressed FTase (but not geranylgeranyltransferase I) in bone marrow and peripheral blood mononuclear cells and also inhibited the farnesylation of HDJ-2 in unfractionated mononuclear cells and purified myeloma cells. Inhibition of farnesylation did not correlate with disease stabilization. Finally, tipifarnib decreased the levels of phosphorylated Akt and STAT3 (signal transducer and activator of transcription 3) but not Erk1/2 (extracellular signal regulated kinase 1 and 2) in bone marrow cells. We conclude that tipifarnib is tolerable, can induce disease stabilization, and can inhibit farnesylation and oncogenic/tumor survival pathways.

Adult↗

PubMed2004

Analysis of somatic hypermutation and antigenic selection in the clonal B cell in immunoglobulin light chain amyloidosis (AL).

Light chain amyloidosis (AL) is a protein folding disorder with an underlying B cell neoplasia where the monoclonal immunoglobulin light chains (LCs) produced from insoluble amyloid fibrils. The deposition of these fibrillar aggregates in vital organs causes severe organ dysfunction over time and is associated with high mortality. We have identified the postgerminal center status of the B cell clone by evaluating the presence of somatic hypermutation in the variable region of the LC gene in 27 (13 of the lambda and 14 of the kappa subtype) AL patients. Seven of the 27 clones showed statistically significant evidence of antigenic selection, using a multinomial algorithm. The framework region mutations were selected for conservation of protein structure in 13 of the 27 patients. Additionally, mutational clusterspots were identified at specific positions in the nucleotide and deduced protein sequence that could potentially contribute to destabilizing interactions resulting in a propensity to form amyloid.

Algorithms↗

PubMed2004

Therapeutic options in patients with lymphoma and severe liver dysfunction.

OBJECTIVES: To determine the long-term outcome of patients presenting with synchronous lymphoma and severe liver dysfunction and to describe the outcome of patients treated with initial mechlorethamine-based therapy used as a bridge to more conventional chemotherapy. PATIENTS AND METHODS: We reviewed the clinical course of all patients diagnosed as having lymphoma who presented with severe liver dysfunction and received intravenous mechlorethamine between September 1988 and February 2003 at the Mayo Clinic in Rochester, Minn. RESULTS: Forty-one patients were identified, 33 (80%) of whom had newly diagnosed, previously untreated lymphoma. Thirty-seven (90%) had non-Hodgkin lymphoma, and 4 (10%) had Hodgkin disease. Thirty-four patients (83%) had stage IV disease, and 31 (84%) of 37 had an intermediate-high International Prognostic Index. The median total bilirubin level before therapy was 10.7 mg/dL (range, 2.5-30.2 mg/dL), and the median alkaline phosphatase level was 982 U/L (range, 233-3415 U/L). In addition to mechlorethamine, 34 patients (83%) received concomitant corticosteroids, and 12 (29%) received concomitant rituximab. Twenty-two patients (54%) had sufficient improvement in liver function to receive subsequent standard chemotherapy. Nine patients (22%) are alive and disease-free at a median of 31 months (range, 4 to > or = 87 months) after mechlorethamine treatment. Factors associated with improved overall survival included improvement in bilirubin levels (P < .001) and receiving subsequent standard chemotherapy (P = .001). CONCLUSION: Mechlorethamine, high-dose corticosteroids, and rituximab are useful therapeutic interventions for this unique group of patients with lymphoma and severe liver dysfunction. Substantial clinical improvement and long-term survival are possible.

Adrenal Cortex Hormones↗