Chronic lymphocytic leukemia

ER Stress and Unfolded Protein Response in Leukemia: Friend, Foe, or Both?

The unfolded protein response (UPR) is an evolutionarily conserved adaptive signaling pathway triggered by a stress of the endoplasmic reticulum (ER) lumen compartment, which is initiated by the accumulation of unfolded proteins. This response, mediated by three sensors-Inositol Requiring Enzyme 1 (IRE1), Activating Transcription Factor 6 (ATF6), and Protein Kinase RNA-Like Endoplasmic Reticulum Kinase (PERK)—allows restoring protein homeostasis and maintaining cell survival. UPR represents a major cytoprotective signaling network for cancer cells, which frequently experience disturbed proteostasis owing to their rapid proliferation in an usually unfavorable microenvironment. Increased basal UPR also participates in the resistance of tumor cells against chemotherapy. UPR activation also occurs during hematopoiesis, and growing evidence supports the critical cytoprotective role played by ER stress in the emergence and proliferation of leukemic cells. In case of severe or prolonged stress, pro-survival UPR may however evolve into a cell death program called terminal UPR. Interestingly, a large number of studies have revealed that the induction of proapoptotic UPR can also strongly contribute to the sensitization of leukemic cells to chemotherapy. Here, we review the current knowledge on the consequences of the deregulation of UPR signaling in leukemias and their implications for the treatment of these diseases.

Delineation of clinical and biological factors associated with cutaneous squamous cell carcinoma among patients with chronic lymphocytic leukemia

BACKGROUND

The incidence of cutaneous squamous cell carcinoma (SCC) in patients with chronic lymphocytic leukemia (CLL) is significantly higher compared with age- and sex-matched controls.

OBJECTIVE

To evaluate the association of factors associated with SCC risk.

METHODS

Clinical CLL and SCC data were obtained from Mayo Clinic CLL Resource and self-reported questionnaires among patients with newly diagnosed CLL. We computed the CLL International Prognostic Index (CLL-IPI) from CLL prognostic factors, and a polygenic risk score from SCC susceptibility variants. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Among 1269 patients with CLL, the median follow-up was 7 years, and SCC subsequently developed in 124 patients. Significant associations with SCC risk were history of skin cancer (HR=4.80; 95% CI: 3.37-6.83), CLL-IPI (HR=1.42; 95% CI: 1.13-1.80), and polygenic risk score (HR=2.58; 95% CI: 1.50-4.43). In a multivariable model, these factors were independent predictors (C statistic = 0.69; 95% CI: 0.62-0.76). T-cell immunosuppressive treatments were also associated with SCC risk (HR=2.29; 95% CI: 1.47-3.55; adjusted for age, sex, and prior SCC).

LIMITATIONS

The sample size decreases when combining all risk factors in a single model.

CONCLUSION

SCC risk includes history of skin cancer, an aggressive disease at time of CLL diagnosis, receiving T-cell immunosuppressive treatments, and high polygenic risk score. Future studies should develop prediction models that include these factors to improved screening guidelines.

Safety and tolerability of conditioning chemotherapy followed by CD19-targeted CAR T cells for relapsed/refractory CLL

BACKGROUND

Subgroups of patients with relapsed or refractory (R/R) chronic lymphocytic leukemia (CLL) exhibit suboptimal outcomes after standard therapies, including oral kinase inhibitors. We and others have previously reported on safety and efficacy of autologous CD19-targeted CAR T-cells for these patients; here we report safety and long-term follow-up of CAR T-cell therapy with or without conditioning chemotherapy for patients with R/R CLL and indolent B-cell non-Hodgkin lymphoma (B-NHL).

METHODS

We conducted a phase 1 clinical trial investigating CD19-targeted CAR T-cells incorporating a CD28 costimulatory domain (19-28z). Seventeen of 20 patients received conditioning chemotherapy prior to CAR T-cell infusion. Five patients with CLL received ibrutinib at the time of autologous T-cell collection and/or CAR T-cell administration.

RESULTS

This analysis included 16 patients with R/R CLL and 4 patients with R/R indolent B-NHL. Cytokine release syndrome (CRS) was observed in all 20 patients but grades 3 and 4 CRS and neurological events were uncommon (10% for each). Ex vivo expansion of T-cells and proportions of CD4+/CD8+ CAR T-cells with CD62L+CD127+ immunophenotype were significantly greater in patients on ibrutinib at leukapheresis. Three of 12 evaluable CLL patients receiving conditioning chemotherapy achieved CR (two had minimal residual disease-negative CR). All patients achieving CR remained progression-free at median follow-up of 53 months.

CONCLUSION

Conditioning chemotherapy and 19-28z CAR T-cells were acceptably tolerated across investigated dose levels in heavily pretreated patients with R/R CLL and indolent B-NHL, and a subgroup of patients achieved durable CR. Ibrutinib therapy may modulate autologous T-cell phenotype.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00466531.

FUNDING

Juno Therapeutics.

Adenovirus Hepatitis: Clinicopathologic Analysis of 12 Consecutive Cases From a Single Institution

Adenoviruses are common pathogens that usually cause self-limited infections. However, in the immunocompromised host they can cause severe infections involving multiple organs including the liver. A search of the pathology database at Stanford University Medical Center (1995 to 2016) identified 12 cases of adenovirus hepatitis including biopsy and autopsy specimens. There were 8 pediatric patients, 7 of which had received orthotropic liver transplants and 1 of which was receiving chemotherapy for lymphoblastic leukemia. There were 4 adult patients, of which 1 was actively receiving chemotherapy for chronic lymphocytic leukemia and 2 had undergone hematopoietic stem cell transplantation for hematologic malignancies. One patient had lymphoplasmacytic lymphoma and had received chemotherapy over a year prior but was not receiving therapy at the time he contracted adenovirus hepatitis. In all cases, histologic sections showed nonzonal coagulative hepatocyte necrosis and characteristic intranuclear inclusions. Hepatocyte necrosis ranged from spotty to massive. The majority of cases (7/12; 58%) had no associated inflammation. If present, inflammation was focal and lymphohistiocytic. In 1 case, findings were focal within the liver, requiring an image-guided biopsy. This patient underwent a simultaneous nontargeted liver biopsy that lacked histologic evidence of adenovirus. Among the pediatric patients, 63% (5/8) died secondary to organ failure, while there was 100% (4/4) mortality in the adult population.

Infections in Hospitalised Patients with Multiple Myeloma: Main Characteristics and Risk Factors

OBJECTIVE

Multiple myeloma is a common haematological malignancy and immune dysfunction is the hallmark of the disease. It leads to an increased infection risk, which is still a major cause of mortality. The infection spectrum and characteristics have evolved with the introduction of novel agents. An understanding of risk factors that increase susceptibility to infections is critical in fighting them. This retrospective investigation aimed to establish the incidence and main characteristics of infections in non-transplanted hospitalised myeloma patients in our department over a 3-year period, as well as factors associated with infections.

MATERIALS AND METHODS

A total of 240 hospitalised patients with multiple myeloma (120 males and 120 females; average age: 69 years, range: 41-89 years) who were diagnosed or treated in our department from January 2008 to December 2010 were included in this study and their data were retrospectively analysed.

RESULTS

Infections were identified in 17.9% of hospitalised patients. The most common pathogen found was Pseudomonas aeruginosa. The frequency of gram-positive and gram-negative pathogens was similar. In 37.2% of cases, the agent was not isolated. The most common sites of infections were the urinary system and the blood (septicemia). The frequency of infection increased with duration of disease and the rate of reinfection was 41.9%. The patients treated with bortezomib had the highest infection occurrence. Fatal outcome occurred in 9.3% of cases.

CONCLUSION

The factors associated with infections in this investigation were female sex, 3B clinical stage of disease, increased serum creatinine and ferritin levels, neutropenia, poor general condition, and presence of catheters. Myeloma patients with one or more of these mentioned risk factors should be monitored with particular care in order to decrease the incidence and severity of infective complications.

mRNA overexpression of kallikrein-related peptidase 14 (KLK14) is an independent predictor of poor overall survival in chronic lymphocytic leukemia patients

BACKGROUND

Tissue kallikrein and kallikrein-related peptidases (KLKs) compose a family of serine endopeptidases with much clinical interest in oncology, as their potential as diagnostic and/or prognostic molecular biomarkers in several human malignancies has already been evidenced. However, none of the members of this family has ever been studied in hematological malignancies. Based on our preliminary results regarding the differential mRNA expression of several KLK genes in peripheral blood mononuclear cells (PBMCs) of patients with chronic lymphocytic leukemia (CLL) compared to healthy blood donors, we decided to study the diagnostic and prognostic potential of KLK14 mRNA expression in CLL.

METHODS

Total RNA was isolated from 69 CLL patients and 31 non-leukemic blood donors. After reverse transcription of poly(A)-RNA, KLK14 mRNA levels were quantified using a sensitive and accurate quantitative real-time PCR (qPCR) methodology.

RESULTS

According to ROC analysis, KLK14 mRNA overexpression successfully discriminated CLL patients from normal population (area under the curve [AUC] 0.89, 95% confidence interval [CI] 0.83-0.95, p<0.001). Moreover, although not clearly related to clinical staging or other prognostic factors including IGHV mutational status and CD38 expression, strong KLK14 mRNA expression was shown to predict reduced overall survival of CLL patients (p=0.026) using Kaplan-Meier survival analysis. The unfavorable prognostic value of KLK14 mRNA overexpression in CLL patients' PBMCs was independent of established prognostic factors of the disease, as shown by multivariate Cox regression analysis (hazard ratio [HR] 14.65, 95% CI 1.81-118.36, p=0.012).

CONCLUSIONS

KLK14 mRNA expression merits further investigation as a potential prognostic biomarker of overall survival of patients with CLL.

Effect of Non-Hodgkin Lymphoma on Survival in Patients With Malignant Fibrous Histiocytoma, Kaposi Sarcoma, and Sebaceous Carcinoma: A SEER Population-Based Study

OBJECTIVE

To quantify the behavior of dermatofibrosarcoma protuberans (DFSP), malignant fibrous histiocytoma (MFH), Kaposi sarcoma (KS), and sebaceous carcinoma (SC) in patients with a history of non-Hodgkin lymphoma (NHL).

PATIENTS AND METHODS

Subjects with a diagnosis of DFSP, MFH, KS, or SC between 1990 and 2006 were identified in the Surveillance, Epidemiology, and End Results Program database. For each skin cancer type, the standardized mortality ratio (SMR) for death due to any cause and death due to skin cancer was estimated.

RESULTS

From 1990 through 2006, 25,357 skin cancers were identified: 4,192 DFSP, 6,412 MFH, 10,543 KS, and 4,222 SC. For patients with a history of non-CLL NHL, SMRs for death due to any cause were 1.45 (95% confidence interval [CI], 1.03-2.04; p = 0.04) for MFH, 2.90 (95% CI, 2.50-3.36; p < 0.001) for KS, and 3.25 (95% CI, 1.84-5.75; p < 0.001) for SC and SMRs for death due to skin cancer were 0.55 (95% CI, 0.23-1.31; p = 0.18) for MFH, 2.93 (95% CI, 2.49-3.43; p < 0.001) for KS, and 4.07 (95% CI, 1.28-12.94; p < 0.001) for SC.

CONCLUSION

Among patients with KS and SC, patients with a history of non-CLL NHL have a greater risk of overall and cause-specific death than expected.

Melanoma in patients with chronic lymphocytic leukemia and non-Hodgkin lymphoma

BACKGROUND

The relationship between melanoma and chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL) has been minimally investigated.

OBJECTIVE

The objective of this study was to examine the incidence of melanoma in patients with a history of CLL or NHL, and their associated mortality.

METHODS

Cohorts of Kaiser Permanente Southern California members with a history of CLL and NHL were identified. Age-adjusted incidence density rates of melanoma among patients with CLL or NHL were compared with rates of melanoma among the general population of Kaiser Permanente Southern California patients. The mortality of patients with melanoma was examined using Cox proportional hazards modeling.

RESULTS

The age-adjusted incidence rate per 100,000 person-years for melanoma among patients with either CLL or NHL was 107 (95% confidence interval 84.4-129.6) versus 25.9 among the general population (95% confidence interval 84.4-129.6, P < .001). Patients with melanoma and a history of CLL or NHL had 2.46 greater odds of death compared with those without CLL or NHL (95% confidence interval 1.77-3.41).

LIMITATIONS

This study was retrospective in nature; the International Classification of Diseases, Ninth Revision codes used may contain diagnostic errors; and only overall survival was used in our analysis.

CONCLUSIONS

Patients with a history of CLL or NHL have a higher incidence of melanoma. Patients with CLL or NHL who are subsequently given the diagnosis of melanoma have a higher mortality than patients with melanoma without a preceding diagnosis of CLL.

The role of telomeres and telomerase in hematologic malignancies and hematopoietic stem cell transplantation

Telomeres are specific nucleoprotein structures at the ends of eukaryotic chromosomes. Telomeres and telomere-associated proteins maintain genome stability by protecting the ends of chromosomes from fusion and degradation. In normal somatic cells, the length of the telomeres gradually becomes shortened with cell division. In tumor cells, the shortening of telomeres length is accelerated under the increased proliferation pressure. However, it will be maintained at an extremely short length as the result of activation of telomerase. Significantly shortened telomeres, activation of telomerase, and altered expression of telomere-associated proteins are common features of various hematologic malignancies and are related with progression or chemotherapy resistance in these diseases. In patients who have received hematopoietic stem cell transplantation (HSCT), the telomere length and the telomerase activity of the engrafted donor cells have a significant influence on HSCT outcomes. Transplantation-related factors should be taken into consideration because of their impacts on telomere homeostasis. As activation of telomerase is widespread in tumor cells, it has been employed as a target point in the treatment of neoplastic hematologic disorders. In this review, the characteristics and roles of telomeres and telomerase both in hematologic malignancies and in HSCT will be summarized. The current status of telomerase-targeted therapies utilized in the treatment of hematologic malignancies will also be reviewed.

Clinical and economic burden of Richter syndrome in inpatient cases of chronic lymphocytic leukemia within the United States, 2001-2010

Richter syndrome (RS) is an aggressive transformation of chronic lymphocytic leukemia (CLL) characterized by poor prognoses. The purpose of this study was to assess clinical and economic characteristics of RS within inpatient hospital settings in the United States from 2001 to 2010. This retrospective cohort study employed data from the Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project. Overall, 46 613 cases of RS were observed across 695 080 inpatient cases of CLL, representing a national bill of $2.74 billion and involving a 9.3% inpatient mortality rate. Multivariate analyses found decreased national inpatient mortality from 2001 to 2010 of - 61.1% (p < 0.001), shorter length of stay of - 15.5% (p < 0.001) and higher charges of +20.9% (p = 0.003). Numerous characteristics were also associated with increased likelihoods of death, lengths of stay and charges. Clinically, the findings allow for an increased understanding of population-based RS case-mixes, outcome prediction and clinical risk assessments. The continued burden of illness of either RS or CLL ultimately remains contingent upon the comparative- and cost-effectiveness of both existing interventions and those in development.

ZAP-70 expression and proliferative activity in chronic lymphocytic leukemia

The expression of 70 kDa protein zeta-associated protein (ZAP-70) in chronic lymphocytic leukemia (CLL) has been used to detect those patients with more aggressive disease. The aim of this study was to determine the proliferative activity of ZAP-70(+) leukemic cells by immunocytochemical methods. The study was undertaken on native blood marrow (BM) and peripheral blood (PB) smears from 65 patients with CLL. ZAP-70 was expressed in leukemic cells of 35 patients (54%). We demonstrated that ZAP-70 immunoreactivity correlated with Rai 0-IV (p = 0.002) and Binet A-C stages (p < 0.001), total tumor mass (TTM score) (p < 0.001), β2-microglobulin (p = 0.006), atypical lymphocytes (p < 0.001) and proliferative activity in bone marrow and peripheral blood (p = 0.014, p = 0.002, respectively) using χ(2) test and Mann-Whitney test. ZAP-70 protein expression is in direct correlation with the poorer prognostic parameters, which additionally confirms the successful method of detection of ZAP-70 expression. Higher Ki-67 expression in BM and PB smears of patients with ZAP-70(+) disease indicates higher proliferating compartments, which may contribute to poorer prognosis.

Melanoma in immunosuppressed patients

The immunogenic characteristics of malignant melanoma are intriguing. To date, multiple studies exist regarding the immunogenicity of melanoma. In this article, we summarize data in the literature on the role of immunosuppression in melanoma and discuss several immunocompromised patient populations in detail. A comprehensive PubMed search was conducted with no date limitation. The following search terms were used: melanoma in combination with immunosuppression, immunocompromised, genetics, antigen processing, UV radiation, organ transplantation, organ transplant recipients, lymphoproliferative disease, lymphoma, CLL, NHL, radiation, and HIV/AIDS. Although no formal criteria were used for inclusion of studies, most pertinent studies on the topic were reviewed, with the exception of smaller case reports and case series. The included studies were generally large (≥ 1000 patients in organ transplant recipient studies; ≥ 500 patients in lymphoma studies), with a focus on institutional experiences, or population-based national or international epidemiologic studies. Melanoma-induced immunosuppression, the role of UV radiation in melanoma development, and the epidemiology, clinical course, and prognosis of melanoma in immunocompromised patients are highlighted. Organ transplant recipients, patients with lymphoproliferative disorders, patients with iatrogenic immunosuppression, and patients with human immunodeficiency virus infection/AIDS are also highlighted. Recommendations are proposed for the care and monitoring of immunosuppressed patients with melanoma. With better understanding of the molecular microenvironment and clinical course of melanoma in immunosuppressed patients, novel therapies could be developed and outcomes potentially affected in these patients.

Serum tumor necrosis factor-α and interleukin-10 levels as markers to predict outcome of patients with chronic lymphocytic leukemia in different risk groups defined by the IGHV mutation status

Tumor necrosis factor (TNF)-α and interleukin (IL)-10 are cytokines involved in the balance between cell-mediated and humoral immunity. We investigated whether serum TNF-α and IL-10 levels have any impact on clinical outcome of patients with chronic lymphocytic leukemia (CLL). TNF-α and IL-10 levels were determined in the serum of 160 CLL patients at the time of diagnosis. The cytokine low-risk group consisted of patients with either TNF-α and IL-10 levels below their medians or those with only one elevated parameter. Both TNF-α and IL-10 levels greater than or equal to their medians defined the cytokine high-risk group. The high-risk patients presented a shorter 3-year treatment-free survival (TFS) than low-risk subjects (15 vs. 69.6 %; p < 0.0001). The high-risk group (p = 0.0002) along with high leukocyte count (p < 0.0001) and unmutated immunoglobulin heavy-chain variable region genes (p < 0.0001) independently predict the risk of progression in patients with Rai stage 0-II. Furthermore, the high-risk group had an independent prognostic impact on shorter TFS both in patients with mutated (24.3 vs. 78.2 %; p < 0.0001) and unmutated (8.2 vs. 49 %; p = 0.004) immunoglobulin heavy-chain variable region genes (IGHV) as compared to the low-risk group. The estimated 5-year overall survival (OS) of high-risk patients was shorter than those in the low-risk group (83.3 vs. 97.1 %; p = 0.003). Multivariate analysis demonstrated the cytokine high-risk group (p = 0.02) followed by Rai stage III-IV (p = 0.048) to be independent factors predicting shorter OS. At diagnosis, TNF-α and IL-10 may predict the outcome of patients with CLL.

Post-transcriptional silencing of Notch2 mRNA in chronic lymphocytic [corrected] leukemic cells of B-CLL patients

Environmental and genomic stresses induce different pathological conditions and one of them is blood cancer. This escalating load of disease with a constant threat to life requires an intensive comprehensive response. For our understanding about the cancer treatment capabilities, novel medicinal platforms should be strived to explore among the existing conventional and molecular approaches that have already been proven to be successful in fighting against genetic diseases. Several DNA therapeutics previously studied are currently in clinical settings. RNA interfering antisense oligonucleotide (AS-ODN) is the most experimentally advanced molecular therapeutic which has the potential to modify the gene activity resulting in the down regulation of particular protein. In this study, we focused on the inhibition of Notch2 function in B-cell chronic lymphocytic leukemia (B-CLL) by AS-ODN (phosphorothioate oligomers) targeted to the initiation codon region of the Notch2 mRNA. We investigated the in vitro ability of four such oligomers to reduce the expression of Notch2 gene in peripheral blood mononuclear cells from B-CLL patients. Our findings implicate that AS-ODNs specifically designed for the region of 314-333 neucleotides (AS1) of Notch2 inhibits its gene expression better than other AS-ODNs designed for other regions and respond in a dose dependent manner. The results of cell proliferation assay for the evaluation of AS1 in gene silencing, infer that the number of cells were reduced to 80% (P < 0.001). Our results implicate that using the AS-ODNs against specific Notch2 nucleotide sequence can be used as future therapeutic agent with the ability of Notch2 down regulation, which is the root problem in the pathogenicity of B-CLL.

Chronic lymphocytic leukemia is associated with decreased survival of patients with malignant melanoma and Merkel cell carcinoma in a SEER population-based study

PURPOSE

To delineate outcomes of malignant melanoma (MM) and Merkel cell carcinoma (MCC) in patients with chronic lymphocytic leukemia (CLL) or non-Hodgkin's lymphoma (NHL).

PATIENTS AND METHODS

We identified patients with MM or MCC reported to the Surveillance, Epidemiology, and End Results program and analyzed the effects of history of CLL/NHL on overall (OS) and cause-specific survival after MM or MCC. Expected survival was derived from patients with MM or MCC without CLL/NHL.

RESULTS

From 1990 to 2006, 212,245 patients with MM and 3,613 patients with MCC were identified, of whom 1,246 with MM and 90 with MCC had a prior diagnosis of CLL/NHL. Patients with MM and a history of CLL/NHL had worse-than-expected OS as measured by standardized mortality ratio (SMR; SMR for CLL, 2.6; 95% CI, 2.3 to 3.0; SMR for NHL, 2.3; 95% CI, 2.1 to 2.6). MM cause-specific survival was worse than expected for patients with a history of CLL (SMR, 2.8; 95% CI, 2.2 to 3.4) or NHL (SMR, 2.1; 95% CI, 1.7 to 2.6). Among patients with MCC, OS was worse than expected for those with a history of CLL (SMR, 3.1; 95% CI, 2.2 to 4.3) or NHL (SMR, 1.9; 95% CI, 1.3 to 2.8). MCC cause-specific survival was worse than expected for patients with a history of CLL (SMR, 3.8; 95% CI, 2.5 to 5.9), but no difference was observed for NHL (SMR, 0.9; 95% CI, 0.4 to 2.1).

CONCLUSION

Patients with CLL before diagnosis of MM or MCC have significantly worse OS and MM or MCC cause-specific survival than those without a history of CLL/NHL.

Telomere length and telomerase levels delineate subgroups of B-cell chronic lymphocytic leukemia with different biological characteristics and clinical outcomes

BACKGROUND

B-cell chronic lymphocytic leukemia is a clinically heterogeneous disease; some patients rapidly progress and die within a few years of diagnosis, whereas others have a long life expectancy with minimal or no treatment. Telomere length and telomerase levels have been proposed as prognostic factors; however, very few cases have been characterized for both parameters and no study has analyzed the prognostic value of the telomere/telomerase profile.

DESIGN AND METHODS

One hundred and seventy-three cases of chronic lymphocytic leukemia were characterized for telomere lengths and telomerase levels by real-time polymerase chain reaction. Data were correlated with established prognostic markers, IGVH mutational status and chromosomal aberrations, and clinical outcome.

RESULTS

Telomere lengths were inversely correlated with telomerase levels (r(s) = -0.213; P = 0.012), and most of the cases of chronic lymphocytic leukemia with high levels (above median) of telomerase had short (below median) telomeres (P = 0.0001). Telomerase levels were higher and telomeres were shorter in unmutated IGVH cases than in mutated IGVH ones (P<0.0001). Chronic lymphocytic leukemias with 11q, 17p deletion or 12 trisomy had significantly higher levels of telomerase and shorter telomeres than those with no chromosomal aberration or the sole 13q deletion (P < 0.001). Telomere length/telomerase level profiles identified subgroups of patients with different clinical outcomes (P < 0.0001), even within the subsets of chronic lymphocytic leukemia defined by IGVH mutational status or chromosomal aberrations. Short telomere/high telomerase profile was independently associated with more rapid disease progression.

CONCLUSIONS

Comprehensive analyses of telomeres, telomerase, chromosomal aberrations, and IGVH mutational status delineate groups of chronic lymphocytic leukemias with distinct biological characteristics and clinical outcomes. The telomere/telomerase profile may be particularly useful in refining the prognosis of chronic lymphocytic leukemia patients with mutated IGVH and no high-risk chromosomal aberrations.

Alterations in TP53, cyclin D2, c-Myc, p21WAF1/CIP1 and p27KIP1 expression associated with progression in B-CLL

B-cell chronic lymphocytic leukaemia (B-CLL) originates from B lymphocytes that may differ in the activation level, maturation state or cellular subgroups in peripheral blood. Tumour progression in CLL B cells seems to result in gradual accumulation of the clone of resting B lymphocytes in the early phases (G0/G1) of the cell cycle. The G1 phase is impaired in B-CLL. We investigated the gene expression of five key cell cycle regulators: TP 53, c-Myc, cyclin D2, p21WAF1/CIP1 and p27KIP1, which primarily regulate the G1 phase of the cell cycle, or S-phase entry and ultimately control the proliferation and cell growth as well as their role in B-CLL progression. The study was conducted in peripheral blood CLL lymphocytes of 40 previously untreated patients. Statistical analysis of correlations of TP53, cyclin D2, c-Myc, p21WAF1/CIP1 and p27KIP1 expressions in B-CLL patients with different Rai stages demonstrated that the progression of disease was accompanied by increases in p53, cyclin D2 and c-Myc mRNA expression. The expression of p27KIP1 was nearly statistically significant whereas that of p21 WAF1/CIP1 showed no such correlation. Moreover, high expression levels of TP53 and c-Myc genes were found to be closely associated with more aggressive forms of the disease requiring earlier therapy.

Increased metastasis of malignant fibrous histiocytoma in patients with chronic lymphocytic leukemia and non-hodgkin lymphoma

OBJECTIVE

To further understand the characteristics and behavior of malignant fibrous histiocytoma (MFH) in the clinical setting of chronic lymphocytic leukemia (CLL) or non-Hodgkin lymphoma (NHL).

PATIENTS AND METHODS

The patient database of MHF diagnosed at our institution from January 1, 1976, to December 31, 2008, was reviewed. For each MFH case with prior NHL or CLL, 3 matched controls from the same cohort without prior CLL or NHL were randomly selected. A retrospective chart review collected patient data, including sex; age; pathologic confirmation of MFH; tumor grade, size, and location; time since MFH diagnosis; history of chemotherapy or irradiation; treatment of MFH; recurrence; metastasis; and death. The Kaplan-Meier method was used to estimate overall survival, survival free of recurrence, and survival free of metastasis. Cox proportional hazards models were fit to evaluate associations between case status and outcomes.

RESULTS

Fifteen MFH cases with prior NHL or CLL were identified. Cases had frequent bone (n=7 [47%]) and cutaneous (n=5 [33%]) involvement. Five cases (33%) had previous irradiation, 6 (40%) had metastases, and 4 (27%) had recurrence. Overall survival and survival free of recurrence were not significantly different between the cases and controls (5-year overall survival, 49.9% and 58.7%; 12-month survival free of recurrence, 79.4% and 90.3%). However, cases were significantly more likely than controls to have metastasis (hazard ratio, 3.79; 95% confidence interval, 1.22-11.79; P=.02). In addition, survival free of metastasis at 12 months was 65.2% and 90.7%, respectively.

CONCLUSION

In the presence of CLL or NHL, MFH seems to behave more aggressively, suggested by the increased likelihood of metastases compared with controls without prior CLL or NHL. However, overall survival does not appear to be worse in cases of MFH and CLL or NHL than in MFH alone.

Telomeres and prognosis in patients with chronic lymphocytic leukaemia

In the present study, telomere length, telomerase activity, the mutation load of immunoglobulin variable heavy chain (IGHV) genes, and established prognostic factors were investigated in 78 patients with chronic lymphocytic leukaemia (CLL) to determine the impact of telomere biology on the pathogenesis of CLL. Telomere length was measured by an automated multi-colour flow-FISH, and an age-independent delta telomere length (ΔTL) was calculated. CLL with unmutated IGHV genes was associated with shorter telomeres (p = 0.002). Furthermore, we observed a linear correlation between the frequency of IGHV gene mutations and elongation of telomeres (r = 0.509, p < 0.001). With respect to prognosis, a threshold ΔTL of -4.2 kb was the best predictor for progression-free and overall survival. ΔTL was not significantly altered over time or with therapy. The correlation between the mutational load in IGHV genes and the ΔTL in CLL might reflect the initial telomere length of the putative cell of origin (pre- versus post-germinal center B cells). In conclusion, the ΔTL is a reliable prognostic marker for patients with CLL. Short telomeres and high telomerase activity as occurs in some patients with CLL with a worse prognosis might be an ideal target for treatment with telomerase inhibitors.

Immunohistochemical detection of ZAP70 in chronic lymphocytic leukemia predicts immunoglobulin heavy chain gene mutation status and time to progression

Zeta-associated protein-70 (ZAP70) expression measured by flow cytometry has been proposed as a surrogate marker of the somatic mutation status of the immunoglobulin heavy chain variable region (IGHV) genes in chronic lymphocytic leukemia. However, attempts to implement this approach in clinical flow cytometry laboratories have been problematic; many commercially available antibodies give unreliable results. Assessment of ZAP70 protein expression by immunohistochemistry in chronic lymphocytic leukemia tissue sections is an easy, alternative approach, although lack of quantitation and subjective interpretation of results are potential pitfalls. In this study, we correlated ZAP70 protein expression, assessed by immunohistochemistry, with ZAP70 messenger RNA (mRNA) transcript expression, assessed by semi-quantitative real-time reverse transcriptase-polymerase chain reaction assay, with the somatic mutation status of the IGHV genes in previously untreated patients with chronic lymphocytic leukemia. Expression of ZAP70 protein and mRNA transcripts correlated strongly (P=8.238 × 10(-12)). Expression of ZAP70 protein and mRNA transcripts also correlated strongly with the somatic mutation status of the IGHV genes (P=0.000071 and P=0.00076, respectively). Further, ZAP70 positivity by immunohistochemistry was associated with an increased risk of progression to therapy requirement (3-year risk 83% vs 31% for ZAP70 negative by immunohistochemistry, P=0.03). These results show that ZAP70 expression assessed by immunohistochemistry is a reliable surrogate marker of the somatic mutation status of the IGHV genes, and predicts time to progression.

The role of chemokines in B cell chronic lymphocytic leukaemia: pathophysiological aspects and clinical impact

Chemokines are centrally involved in leukocyte migration, homing and haematopoiesis. Besides these physiological aspects, their role in pathological processes especially with respect to solid tumour and haematological neoplasias is well established. In this context, the focus was set here on disclosing their contribution in B cell chronic lymphocytic leukaemia (B-CLL), which is regarded as the most characteristic low-grade lymphoma. Up to now, it has been demonstrated that several chemokines are involved in migration of B-CLL cells to lymph nodes, secondary lymphoid organs and bone marrow. Moreover, some chemokines are known to have an anti-apoptotic effect and thus contribute to the survival of B-CLL cells. By interfering with both of these aspects, new therapeutic targets for this yet incurable disease may be developed. Furthermore, a correlation can be drawn between the concentration of some chemokines in patients' serum, the expression of their respective receptors on B-CLL cells and well-established predictive clinical parameters. Consequently, further systematic investigation of the chemokine network may lead to the identification of new diagnostic and prognostic markers. This review focuses on the impact of chemokines and their receptors on B-CLL pathophysiology and points out potential implications for both treatment and diagnosis.

NOTCH2 links protein kinase C delta to the expression of CD23 in chronic lymphocytic leukaemia (CLL) cells

One characteristic of chronic lymphocytic leukaemia (CLL) lymphocytes is high expression of CD23, which has previously been identified as a downstream target for NOTCH2 signalling. The mechanisms regulating NOTCH2-dependent CD23 expression, however, are largely unknown. This study showed that peripheral CLL cells overexpressed transcriptionally active NOTCH2 (N2(IC)), irrespective of their prognostic marker profile. When placed in culture, NOTCH2 activity was spontaneously decreased in 25 out of 31 CLL cases (81%) within 24 h. DNA-bound N2(IC) complexes could be maintained by the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) or by gamma-interferon (IFN-gamma), two CLL characteristic inducers of CD23 expression. Inhibition of PKC-delta by RNA interference or by rottlerin antagonised PMA-induced NOTCH2 activation and also suppressed NOTCH2 activity in CLL cases with constitutively activated NOTCH2 signalling. In 23 out of 29 CLL cases tested (79%), DNA-bound N2(IC) complexes were found to be resistant to the gamma-secretase inhibitor (GSI) DAPT, suggesting that GSIs will be only effective in a subset of CLL cases. These data suggest that deregulation of NOTCH2 signalling is critically involved in maintaining the malignant phenotype of CLL lymphocytes and point to a link between PKC-delta and NOTCH2 signalling in the leukemic cells.

Effects of Preactivated Autologous T Lymphocytes on CD80, CD86 and CD95 Expression by Chronic Lymphocytic Leukemia B Cells

Profound immune dysfunction is a constant feature in B-cell chronic lymphocytic leukemia (B-CLL) patients. Immunological abnormalities include hypogammaglobulinemia, impaired immunoglobulin class switching and diminished germinal center formation. This state of immune suppression renders B-CLL patients highly susceptible to infections, which contribute greatly to morbidity and mortality in this disease. Impaired T cell function in B-CLL is well-documented and has been suggested to result from inhibitory effects exerted by malignant B lymphocytes. Because the presence of leukemic cells may represent a major obstacle to efficient T cell activation, T lymphocytes were separated from CLL B cells, stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin for 4h, and then cocultured with autologous leukemic B cells both at a 1:1 ratio or at the same ratio as in vivo for 24-40 h. CLL B cell expression of CD86 and CD95 was markedly upregulated using this approach, whereas CD80 expression was augmented only in a minority of patients; these effects were partially preserved even when preactivated T cells were rechallenged with CLL B cells at the same low T/B cell ratio as that observed in vivo. Finally, CD80 upregulation on CLL B cells appeared to be mainly dependent on CD40L-mediated stimulation, whereas CD86 and CD95 expression was efficiently augmented by soluble factors released by preactivated T lymphocytes. In conclusion, efficient activation of T lymphocytes in B-CLL may be achieved which, in turn, may result in enhanced antigen-presenting capacity and susceptibility to apoptosis of leukemic cells via CD86 and CD95 upregulation, respectively.

Gene expression signature of chronic lymphocytic leukaemia with Trisomy 12

BACKGROUND

The prognosis of chronic lymphocytic leukaemia (CLL) patients is largely determined by the karyotype of the malignant clone. We have investigated the gene expression profile associated with trisomy 12 (+12).

DESIGN

Initially, unselected peripheral blood mononuclear cells of four patients with +12 were compared with 16 CLL controls using microarray analysis.

RESULTS

were validated by quantitative real-time PCR with RNA from 61 patients (29 with +12, 32 CLL controls). Results Seven genes showing the strongest correlation with +12 in microarray analysis were selected for real-time PCR: HIP1R, MYF6, SLC2A6, CD9 (overexpressed); CD200, P2RY14, RASGRP3 (underexpressed). Four genes were significantly associated with +12: HIP1R (P<0.0001), MYF6 (P=0.007), P2RY14 (P=0.014), CD200 (P=0.028). Receiver Operating Characteristic curve analysis revealed that HIP1R expression was a highly sensitive and specific marker for +12 in CLL patients. MYF6 was exclusively expressed in normal or malignant B cells in peripheral blood but was poorly predictive for +12. As expected, a number of overexpressed genes are located on chromosome 12 (HIP1R, MYF6). Interestingly, both significantly underexpressed genes (P2RY14, CD200) reside on the long arm of chromosome 3 pointing to trans-repression in this region.

CONCLUSIONS

Analysis of the molecular signature of trisomy 12 in CLL resulted in: (i) identification of a surrogate marker for PCR (HIP1R); (ii) observation of a gene dosage effect; and (iii) detection of specific underexpression of genes located on chromosome 3. These results should help to improve diagnosis and treatment decisions for patients with CLL and trisomy 12.

Combinations of ZAP-70, CD38 and IGHV mutational status as predictors of time to first treatment in CLL

ZAP-70, CD38 and IGHV mutations have all been reported to have prognostic impact in chronic lymphocytic leukemia (CLL), both individually and in paired combinations. We aimed to determine whether the combination of all three factors provided more refined prognostic information concerning the treatment-free interval (TFI) from diagnosis. ZAP-70, CD38 and IGHV mutations were evaluated in 142 patients. Combining all three factors, the ZAP-70-/CD38-/Mutated group showed the longest median TFI (62 months, n = 37), ZAP-70+/CD38+/Unmutated cases the shortest (11 months, n = 37) and cases discordant for > or = 1 factor, an intermediate TFI (27 months, n = 68) (p = 0.006). Analysis of discordant cases revealed values that were otherwise masked when measuring single prognostic factors. The presence or absence of cytogenetic abnormalities did not explain the variability among discordant cases. Simultaneous analysis of ZAP-70, CD38 and IGHV mutations in CLL provides more discriminatory prediction of TFI than any factor alone.

Constitutively activated Notch signaling is involved in survival and apoptosis resistance of B-CLL cells

Notch signaling is involved in tumorigenesis, but its role in B-chronic lymphocytic leukemia (B-CLL) pathogenesis is not completely defined. This study examined the expression and activation of Notch receptors in B-CLL cells and the role of Notch signaling in sustaining the survival of these cells. Our results show that B-CLL cells but not normal B cells constitutively express Notch1 and Notch2 proteins as well as their ligands Jagged1 and Jagged2. Notch signaling is constitutively activated in B-CLL cells, and its activation is further increased in B-CLL cells, which resist spontaneous apoptosis after 24-hour ex vivo culture. Notch stimulation by a soluble Jagged1 ligand increases B-CLL cell survival and is accompanied by increased nuclear factor-kappa B (NF-kappaB) activity and cellular inhibitor of apoptosis protein 2 (c-IAP2) and X-linked inhibitor of apoptosis protein (XIAP) expression. In contrast, Notch-signaling inhibition by the gamma-secretase inhibitor I (GSI; z-Leu-Leu-Nle-CHO) and the specific Notch2 down-regulation by small-interfering RNA accelerate spontaneous B-CLL cell apoptosis. Apoptotic activity of GSI is accompanied by reduction of NF-kappaB activity and c-IAP2 and XIAP expression. Overall, our findings show that Notch signaling plays a critical role in B-CLL cell survival and apoptosis resistance and suggest that it could be a novel potential therapeutic target.

Progressive trichodysplasia spinulosa in a patient with chronic lymphocytic leukaemia in remission

A 70-year old Caucasian man with chronic lymphocytic leukaemia developed trichodysplasia spinulosa 2 months after ceasing chemotherapy. Histological features characteristic to this condition include dilated and enlarged hair follicles, hyperplastic hair bulbs, hyperplasia of inner root sheath cells with numerous large, eosinophilic, trichohyaline granules, and hypercornification. Although he was in remission for chronic lymphocytic leukaemia, lesions were slowly progressive 15 months after cessation of chemotherapy. We also describe a painless pull-test where spicules can be easily plucked and assessed microscopically for inner root sheath keratinization, or observed with surface microscopy in a clinic setting.

Short telomeres are associated with genetic complexity, high-risk genomic aberrations, and short survival in chronic lymphocytic leukemia

Telomere length is associated with mutation status of the immunoglobulin heavy chain variable (IGHV) gene and clinical course in B-cell chronic lymphocytic leukemia (B-CLL). In a B-CLL cohort of 152 patients, we analyzed telomere length, genomic aberrations, IGHV mutation status, CD38 and ZAP-70 expression to study the prognostic impact and associations among these factors. An inverse correlation existed between telomere length and IGHV homology (P < .001), CD38 (P < .001), and ZAP-70 expression (P = .01). Patients with telomere lengths below median (ie, “short telomeres”) and above median (ie, “long telomeres”) had similar incidences of genomic aberrations (74% vs 68%), 13q− (57% vs 49%), and +12q (5% vs 12%). In contrast, 13q− as a single aberration was more frequent in patients with long telomeres (51% vs 21%; P = .006), whereas 11q− (27% vs 9%; P = .014), 17p− (17% vs 0%; P < .001), and 2 or more genomic aberrations (39% vs 8%; P < .001) were more frequent in patients with short telomeres. Compared with patients with long telomeres, treatment-free survival (TFS) and overall survival (OS) was significantly shorter (P < .001 and P = .015, respectively) in the group with short telomeres, and telomere length was an independent prognostic indicator for TFS. These observations have biological and prognostic implications in B-CLL.

Telomerase expression in B-cell chronic lymphocytic leukemia predicts survival and delineates subgroups of patients with the same igVH mutation status and different outcome

Activation of telomerase reverse transcriptase (hTERT) is essential for unlimited cell growth and plays a critical role in tumorigenesis. We investigated hTERT gene expression in 134 B-cell chronic lymphocytic leukemia (B-CLL) cases and evaluated its prognostic value with other prognostic markers (IgVH mutation status, CD38 and ZAP-70 expression). Real-time PCR assays to quantify either all hTERT transcripts (AT) or only the full length (FL) transcript encoding the functional protein were developed. hTERT-AT levels strongly correlated with hTERT-FT levels (r=0.743, P<0.0001); both inversely correlated with the percentage of IgVH mutation (P<0.005) and were significantly higher in unmutated than in mutated cases (P=0.004 and P=0.001, respectively). The hTERT values which best discriminated between the unmutated and mutated IgVH cases were 150 and 40 copies for hTERT-AT and hTERT-FL, respectively. Using these cut-off values, there was a significant difference in the survival of patients with high or low hTERT levels (P<0.0001). Unmutated cases with low hTERT levels had an overall survival close to mutated cases with high hTERT levels. Thus, this work identifies hTERT-RNA level as a new prognostic marker in B-CLL, and may be used to identify previously unrecognized patient groups with the same IgVH mutation status and different disease outcomes.

Flow cytometric detection of ZAP-70 in chronic lymphocytic leukemia: correlation with immunocytochemistry and Western blot analysis

CONTEXT

Expression of ZAP-70 in chronic lymphocytic leukemia (CLL) predicts worse clinical outcome in patients with early-stage disease. It has become important to include ZAP-70 in the immunophenotyping panel used to diagnose CLL, commonly performed by flow cytometry (FC). Nevertheless, the methodology used to detect ZAP-70 by FC has not been extensively evaluated.

OBJECTIVE

To describe our FC method for detecting ZAP-70 in CLL and assess whether this assay is useful in estimating the ZAP-70 protein level in CLL cells.

DESIGN

ZAP-70 expression was assessed by FC in 45 consecutive newly diagnosed CLL patients, and the results were correlated with those of immunocytochemistry and Western blot analysis.

RESULTS

With >25% ZAP-70-positive B cells as the cutoff, the FC results had a perfect concordance with those of immunocytochemistry (39/39, 100%) and Western blot analysis (7/7, 100%). The use of autofluorescence controls was found to be superior to other alternatives. Overall, 19 (42%) of 45 cases were ZAP-70 positive in our series. Since only 7 cases (16%) had >20% to 30% ZAP-70-positive B cells, the cutoff of >25% readily separated CLL into positive and negative groups in most cases. ZAP-70 positivity was significantly associated with atypical morphology but not other laboratory parameters evaluated.

CONCLUSIONS

With proper specimen processing and the use of directly fluorescence-conjugated anti-ZAP-70 antibody, one can readily incorporate ZAP-70 into the routine FC study panel for CLL. Our data suggest that FC is a rapid and useful method to estimate the ZAP-70 protein expression level in CLL.

Bone biopsy derived marrow stromal elements rescue chronic lymphocytic leukemia B-cells from spontaneous and drug induced cell death and facilitates an "angiogenic switch"

A novel bone biopsy technique was used to generate a robust stromal cell system to study how stroma modulates CLL B-cell apoptosis and how the leukemic cell-stromal interaction influences secretion of vascular factors. Marrow stromal elements (MSE) rescued CLL B-cells from both spontaneous and drug induced apoptosis, partly due to soluble factors. When CLL B-cells were added to the MSE cultures, a dramatic increase in the secretion of basic fibroblast growth factor and decrease in the secretion of thrombospondin was observed. These results indicate the interaction between CLL B-cells and marrow stromal elements regulates angiogenic switching and may be linked to disease progression.

Signaling molecules and cytokine production in T cells of patients with B-cell chronic lymphocytic leukemia: long-term effects of fludarabine and alemtuzumab treatment

Fludarabine and alemtuzumab are routinely used for treatment of B-cell chronic lymphocytic leukemia (B-CLL). The present study aimed to compare the expression of signaling molecules and cytokine production by T cells of B-CLL patients in long-term unmaintained remission/plateau phase following fludarabine or alemtuzumab treatment with that of indolent/untreated B-CLL patients and healthy donors. The frequency and intensity of TCR-CD3zeta chain, p56lck, p59fyn, ZAP-70, PI3-kinase and interferon (IFN)-gamma/interleukin (IL)-4 production in CD4 and CD8 T cells was examined by flow cytometry. T-cell function was assessed by stimulation with purified protein derivative (PPD) and phytohemagglutinin (PHA). Despite a reduction in number, the expression of IFN-gamma/IL-4 in T-cells in patients was significantly higher than in healthy donors. The intensity of most signaling molecules in treated patients was relatively unaffected vs. healthy donors but lower than untreated-indolent patients. However, the total number of T cells which expressed each of the signaling molecules was decreased in patients, with no difference between fludarabine- and alemtuzumab-treated patients. The T-cell response to PHA but not PPD was reduced in treated patients. The results suggest that, despite some alterations in signaling molecules and a reduction in T-cell number, overall T-cell functions may be relatively well preserved long-term after treatment with fludarabine and alemtuzumab.

Non-Hodgkin lymphoma and skin cancer: A dangerous combination

There is a significant association between non-Hodgkin lymphoma, including chronic lymphocytic leukaemia, and both melanoma and non-melanoma skin cancer. This review highlights the existing data on the phenomenon of accelerated skin cancer in patients with non-Hodgkin lymphoma and specifically chronic lymphocytic leukaemia. The outcomes of patients with non-Hodgkin lymphoma (including chronic lymphocytic leukaemia) and non-melanoma skin cancer are worse than in patients without concomitant lymphoreticular malignancy, as shown by increased rates of local recurrence, regional metastasis and death. Pathogenic factors may be common between non-Hodgkin lymphoma and chronic lymphocytic leukaemia and skin cancer. The treatment of skin cancer in patients with non-Hodgkin lymphoma must factor in the worse prognosis and adapt standard therapeutic approaches to minimize the risk of metastasis and death. Preventive strategies and early detection are paramount in this high-risk population.

B cell chronic lymphocytic leukaemia/small lymphocytic lymphoma: role of ZAP70 determination on bone marrow biopsy specimens

BACKGROUND

The course of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) partly depends on the mutational status of the variable region of immunoglobulin heavy chain genes (IgV(H)), which defines two subgroups of tumours: mutated and unmutated. The expression of zeta-associated protein 70 (ZAP70) is significantly associated with the more aggressive unmutated forms.

AIMS

To assess the feasibility of the ZAP70 immunohistochemical test on bone-marrow biopsy (BMB) specimens and to compare the results with those of western blotting (WB) and IgV(H) mutational status assessed on neoplastic cells from peripheral blood.

METHODS

26 patients with CLL/SLL detected on BMB and with known IgV(H) mutational status were selected. ZAP70 was determined by immunohistochemistry (IHC) comparing three antibodies from different sources (Upstate, Cell Signaling, Santa Cruz, California, USA) and two different methods (APAAP and EnVision(+)). In 23 cases, ZAP70 WB results were also available.

RESULTS

ZAP70 determination on BMB specimens turned out to be easily feasible with routine procedures with reagents from Upstate and Cell Signaling. The results were concordant with those obtained with WB and mutational status analysis in >80% of the cases with both reagents. Three of four discordant cases were mutated/ZAP70 positive, with two staining weakly for ZAP70 on both WB and IHC.

CONCLUSIONS

The study confirms the role of ZAP70 as a possible surrogate of mutational status and emphasises its application in routine diagnostics; it discloses a small subset of discordant cases (mutated/ZAP70 weakly positive) that clinically cluster with the more favourable forms.

Increased metastasis and mortality from cutaneous squamous cell carcinoma in patients with chronic lymphocytic leukemia

In patients with chronic lymphocytic leukemia, squamous cell carcinoma behaves aggressively. Our purpose was to compare squamous cell carcinoma metastasis and mortality between patients with chronic lymphocytic leukemia and control subjects. Medical records were assessed retrospectively for 28 patients with chronic lymphocytic leukemia who underwent surgical excision of cutaneous squamous cell carcinoma and for 56 matched control subjects. The rate of metastasis and mortality from cutaneous squamous cell carcinoma were determined on a per-patient basis. Three of 28 patients with chronic lymphocytic leukemia had metastasis and died of metastatic disease. No metastases or deaths occurred among the 56 control subjects. Compared with control subjects, chronic lymphocytic leukemia patients with cutaneous squamous cell carcinoma were more likely to have metastasis (P = .0031) and die of metastasis (P = .0033). No significant association was detected between metastasis and history of chemotherapy administration for chronic lymphocytic leukemia. Among patients with chronic lymphocytic leukemia, surveillance for skin cancer and a decreased threshold for biopsy of suspect lesions are warranted.

The clinical significance of ZAP-70 and CD38 expression in B-cell chronic lymphocytic leukaemia

BACKGROUND

B-cell chronic lymphocytic leukaemia (B-CLL) is a disease with a highly variable clinical course; some patients never need treatment, while others require intensive treatment early after diagnosis. Recently, some new prognostic factors, such as IgVH mutational status, ZAP-70 and the expression of CD38 in leukaemic cells were introduced to identify attenuated versus progressive types of CLL bearing the potential to facilitate risk-adapted treatment strategies.

PATIENTS AND METHODS

To evaluate the clinical value of ZAP-70 and CD38 as predictors of disease progression we assessed the expression of these markers by the flow cytometry method in 156 B-CLL patients.

RESULTS AND CONCLUSIONS

Both ZAP-70 and CD38 expression were shown to predict the clinical course of the disease, while ZAP-70 expression appeared to be more predictive than CD38 expression and more relevant in defining the cases of B-CLL responsive or refractory to first line chemotherapy. A simultaneous evaluation of ZAP-70 and CD38 expression allowed distinguishing the patients groups with the most favourable prognosis as well as those with the worst. Taken together we recommend assessing both ZAP-70 and CD38 protein expression for the definition of prognostic subgroups in patients with B-CLL.

Risk of bacteraemia and mortality in patients with haematological malignancies

This study examined the association between type of haematological malignancy, risk of bacteraemia and risk of mortality, with emphasis on the impact of bacteraemia type on mortality. A population-based cohort design was used, and all patients aged > or = 15 years with an incident haematological malignancy who were living in North Jutland County, Denmark, during 1992-2002 were included in the study. Among 1666 patients with an incident haematological malignancy, 358 (21%) suffered an episode of bacteraemia during a median follow-up period of 1.1 years (quartile 0.2-3.4) from the date of cancer diagnosis (overall incidence rate of 96/1000 person-years). In comparison to Hodgkin's disease, adjusted incidence rate ratios (IRRs) were 23.3 (95% CI, 10.0-54.5) for acute myeloid leukaemia, 3.8 (95% CI, 1.5-9.3) for multiple myeloma, and 2.2 (95% CI, 0.9-5.1) for non-Hodgkin's lymphoma or chronic lymphatic leukaemia. Overall cumulative 30-day mortality was 32% (95% CI, 27-37), and 90-day mortality was 50% (95% CI, 44-55). In comparison with acute myeloid leukaemia, adjusted mortality rate ratios (MRRs) were close to 1.0 for other haematological malignancies. In comparison to bacteraemia caused by Gram-positive bacteria, adjusted MRRs were 1.0 (95% CI, 0.6-1.5) for Gram-negative bacteraemia, and 1.9 (95% CI, 1.1-3.3) for polymicrobial bacteraemia or fungaemia. Thus, the risk of bacteraemia varied greatly according to the type of malignancy, while mortality rates were similar for these diseases, although dependent on the type of bacteraemia. Polymicrobial bacteraemia or fungaemia was associated with higher mortality.

Is targeted chemotherapy an alternative to immunotherapy in chronic lymphocytic leukemia?

Although molecular remission is now detected, it is still unknown whether we have the tools to cure B cell chronic lymphocytic leukemia (referred to as CLL). Nonetheless, several new therapeutic approaches have been introduced in cancer therapy during the last decade, including antiangiogenic therapy, apoptosis-inducing treatment and inhibition of heat shock proteins, farnesyl transferase, tyrosine kinases and proteasomes. These modalities may also be considered in CLL, but additional experimental characterization is required. Further characterization and development of CLL animal models should be a part of this preclinical work (especially xenografting in NOD/SCID animals, but also murine leukemia) to allow a more extensive evaluation prior to clinical trials. Animal models are particularly important for preclinical comparison of pharmacological effects between different disease compartments and for in vivo evaluation of antileukemic immune reactivity. However, T cell targeting therapy seems to have several advantages in comparison to other approaches: (1) based on the current clinical experience one would expect low toxicity for several of these strategies, especially vaccine treatment; (2) several studies have demonstrated that autologous T cells can recognize CLL cells; (3) experimental and clinical evidence suggests that immunotherapy can be combined with chemotherapy. Thus, T cell therapy has a relatively strong scientific basis that justifies further clinical studies of immunotherapy in CLL. Although several of the new pharmacological agents seem to have immunosuppressive effects, at least some of them (e.g. heat shock protein 90 inhibitors, proteasome inhibitors, inhibition of angiogenesis) appear to affect T cells only at relatively high concentrations and may thus be used in combination with immunotherapy.

Induction of CD95 upregulation does not render chronic lymphocytic leukemia B-cells susceptible to CD95-mediated apoptosis

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by a progressive accumulation of long-lived and well-differentiated clonal B-lymphocytes in peripheral blood, lymphoid tissue and bone marrow. Although B-CLL pathogenesis is not entirely understood, the progressive increase in lymphocyte counts coupled with the very low proportion of proliferating cells suggests that B-CLL may be primarily determined by defective apoptosis. Consistently, freshly analyzed CLL B-cells express very low levels of membrane CD95, one of the best-known receptors involved in triggering apoptosis. In this study, CD95 upregulation on CLL B-cells was induced by culturing clonal B-cells in the presence of supernatants from preactivated autologous T-lymphocytes. Intracellular cytokine staining of preactivated autologous T-lymphocytes using monoclonal antibodies (moAbs) specific for Th1 or Th2 cytokines, namely interleukin (IL)-2, IL-4, IL-5, IL-10 and interferon (IFN)-gamma, showed these cells to be positive for IL-2 and IFN-gamma. Blocking experiments using moAbs specific for IL-2 and/or IFN-gamma revealed that CD95 upregulation on CLL B-cells was mainly driven by IFN-gamma. However, CD95-expressing CLL B-cells were demonstrated to be resistant to CD95-mediated apoptosis, thus arguing against strategies aimed at exploiting CD95-mediated apoptosis for immunotherapy of B-CLL.

Autocrine VEGF mediates the antiapoptotic effect of CD154 on CLL cells

CD154 is an important regulator of chronic lymphocytic leukaemia (CLL)-cell survival. In CLL, high serum levels of VEGF are a feature of advanced disease, and we and others have previously shown that CLL cells produce and secrete this growth factor. Since CD154 stimulates VEGF production in other cell types, and VEGF is known to promote cell survival, we examined whether the cytoprotection of CLL cells by CD154 involves VEGF. We report for the first time that treatment of CLL cells with CD154 results in increased VEGF production and demonstrate involvement of NF-kappaB in this process. Moreover, we show that CD154-induced CLL-cell survival is reduced by anti-VEGF-neutralising antibody and by inhibiting VEGF receptor (VEGFR) signalling with SU5416. However, addition of exogenous VEGF alone or blocking secreted autocrine VEGF had little or no effect on CLL-cell survival. We therefore conclude that CLL-cell cytoprotection in the presence of CD154 requires combined signalling by both CD40 and VEGFR. This combined signalling and resulting cytoprotection were shown to involve NF-kappaB activation and increased survivin production. In conclusion, our findings identify autocrine VEGF as an important mediator of the antiapoptotic effect of CD40 ligation, and thus provide new insights into CLL-cell rescue by CD154 in lymphoreticular tissues.

High expression of lipoprotein lipase in poor risk B-cell chronic lymphocytic leukemia

We investigated the pattern of lipoprotein lipase (LPL) expression in B-cell chronic lymphocytic leukemia (B-CLL) and assessed its prognostic relevance. Expression of LPL mRNA as well as protein was highly restricted to leukemic B cells. The intensity of intracellular immunoreactivity of LPL was higher in samples of patients with unmutated immunoglobulin heavy-chain variable region genes (IGV(H)) compared to those with mutated IGV(H) genes. LPL mRNA levels in peripheral blood mononuclear cells (PBMNC) from 104 CLL patients differed by 1.5 orders of magnitude between cases with mutated (N=51) or unmutated (N=53) IGV(H) (median: 1.33 vs 45.22 compared to normal PBMNC). LPL expression correlated strongly with IGV(H) mutational status (R=0.614; P<0.0001). High LPL expression predicted unmutated IGV(H) status with an odds ratio of 25.90 (P<0.0001) and discriminated between mutated and unmutated cases in 87 of 104 patients (84%). LPL expression was higher in patients with poor risk cytogenetics. High LPL expression was associated with a shorter treatment-free survival (median 40 vs 96 months, P=0.001) and a trend for a shorter median overall survival (105 months vs not reached). Our data establish LPL as a prognostic marker and suggest functional consequences of LPL overexpression in patients with B-CLL.

Fludarabine-induced apoptosis in CD19+/CD5+B-CLL cells is a direct and nurse-like-cell independent effect

B-cell chronic lymphocytic leukemia (B-CLL) is a hematological malignancy characterized by the accumulation of mature CD5+ B lymphocytes with a defective apoptosis. A subset of blood monocyte-derived adherent cells generated in vitro protects B-CLL cells from apoptosis playing a role as nurse-like cells (NLCs). Fludarabine (9-beta-D-arabinofuranosyl-2-fluoroadenine; F-ara-A) is an adenine nucleoside analog used to treat B-CLL. To gain insight into the mechanisms implicated in the antitumoral effect of fludarabine in B-CLL cells, we performed cross-cultures with B-CLL cells and NLCs treated and untreated with fludarabine. Our results showed that fludarabine blocked the development of NLCs and induced apoptosis in these cells when they were present in culture. Moreover, CD19+/CD5+B-CLL cells treated with fludarabine underwent apoptosis and this event was not related with the presence of NLCs whether treated or not with fludarabine. In conclusion, apoptosis induced by fludarabine in CD19+/CD5+B-CLL cells was due to a direct effect on these cells and not due to its effect in the NLCs.