Health practice in long-term survivors of Hodgkin's lymphoma.

PURPOSE: To compare the health practice of Hodgkin's lymphoma (HL) survivors and their siblings, and to assess the impact of socioeconomic status and disease history on health practice of HL survivors. METHODS AND MATERIALS: We conducted a questionnaire study on long-term HL survivors and their siblings on health care utilization, health habits, and screening behavior. RESULTS: A total of 511 HL survivors (response rate of 50%, including survivors lost to contact) and 224 siblings (response rate, 58%) participated. Median time from HL diagnosis was 15 years. Significantly more survivors than siblings had a physical examination in the past year (63% vs. 49%, p = 0.0001). Male survivors were significantly more likely than siblings to perform monthly self-testicular examinations (19% vs. 9%, p = 0.02). Among survivors, higher household income (p = 0.01) independently predicted for having had a physical examination in the past year. Lower educational level (p = 0.0004) and history of relapsed HL (p = 0.03) were independent predictors for smoking, moderate/heavy alcohol use, and/or physical inactivity. CONCLUSIONS: Compared with siblings, long-term HL survivors have a higher level of health care utilization and better screening practice. Survivors from lower socioeconomic background had lower adherence to routine health care and greater report of unhealthy habits. Survivors with history of relapsed HL were also more likely to engage in unhealthy habits.

Improved survival of patients with human papillomavirus-positive head and neck squamous cell carcinoma in a prospective clinical trial.

BACKGROUND: The improved prognosis for patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) relative to HPV-negative HNSCC observed in retrospective analyses remains to be confirmed in a prospective clinical trial. METHODS: We prospectively evaluated the association of tumor HPV status with therapeutic response and survival among 96 patients with stage III or IV HNSCC of the oropharynx or larynx who participated in an Eastern Cooperative Oncology Group (ECOG) phase II trial and who received two cycles of induction chemotherapy with intravenous paclitaxel and carboplatin followed by concomitant weekly intravenous paclitaxel and standard fractionation radiation therapy. The presence or absence of HPV oncogenic types in tumors was determined by multiplex polymerase chain reaction (PCR) and in situ hybridization. Two-year overall and progression-free survival for HPV-positive and HPV-negative patients were estimated by Kaplan-Meier analysis. The relative hazard of mortality and progression for HPV-positive vs HPV-negative patients after adjustment for age, ECOG performance status, stage, and other covariables was estimated by use of a multivariable Cox proportional hazards model. All statistical tests were two-sided. RESULTS: Genomic DNA of oncogenic HPV types 16, 33, or 35 was located within tumor cell nuclei of 40% (95% confidence interval [CI] = 30% to 50%) of patients with HNSCC of the oropharynx or larynx by in situ hybridization and PCR. Compared with patients with HPV-negative tumors, patients with HPV-positive tumors had higher response rates after induction chemotherapy (82% vs 55%, difference = 27%, 95% CI = 9.3% to 44.7%, P = .01) and after chemoradiation treatment (84% vs 57%, difference = 27%, 95% CI = 9.7% to 44.3%, P = .007). After a median follow-up of 39.1 months, patients with HPV-positive tumors had improved overall survival (2-year overall survival = 95% [95% CI = 87% to 100%] vs 62% [95% CI = 49% to 74%], difference = 33%, 95% CI = 18.6% to 47.4%, P = .005, log-rank test) and, after adjustment for age, tumor stage, and ECOG performance status, lower risks of progression (hazard ratio [HR] = 0.27, 95% CI = 0.10 to 0.75), and death from any cause (HR = 0.36, 95% CI = 0.15 to 0.85) than those with HPV-negative tumors. CONCLUSION: For patients with HNSCC of the oropharynx, tumor HPV status is strongly associated with therapeutic response and survival.

Phase II trial of chemoradiation for organ preservation in resectable stage III or IV squamous cell carcinomas of the larynx or oropharynx: results of Eastern Cooperative Oncology Group Study E2399.

PURPOSE: Taxane-based concurrent chemoradiotherapy (CCR) for head and neck cancers has proven to have a favorable toxicity profile compared with cisplatin and radiation. This phase II multi-institutional trial evaluates taxane-based induction chemotherapy followed by CCR for organ preservation in resectable stage III/IVA and IVB larynx and oropharynx (OP) cancer patients. PATIENTS AND METHODS: Eligibility required resectable stage T2N+, or T3-T4N0-3M0 biopsy-proven squamous carcinoma, age at least 18 years, PS 0 to 2, good organ function, and no prior chemotherapy or radiation. Treatment was induction paclitaxel 175 mg/m(2) and carboplatin area under the concentration-time curve (AUC) 6 for two cycles every 21 days followed by concurrent paclitaxel 30 mg/m(2) every 7 days with 70 Gy if no evidence of tumor progression. Weekly erythropoietin alpha 40 kU was used for suboptimal hemoglobin (< 14 gm/dL men, < 13 gm/dL women). The primary end point was organ preservation (freedom from primary site salvage surgery or primary tumor recurrence). RESULTS: One hundred five of 111 patients (36 larynx, 69 OP) were eligible. Median follow-up was 36.7 months. Ninety-four percent received full-dose radiotherapy and 91% received at least five cycles of concurrent paclitaxel. No patient progressed while receiving chemotherapy. Organ preservation was 81% at 2 years after completion of therapy (larynx 74%, OP 84%). Thirteen patients required primary-site salvage surgery (seven larynx, six OP), and six of these have progressed and died (three larynx, three OP). Thirteen patients developed distant metastases (seven larynx, six OP; P = .02) and 10 of 36 larynx and 11 of 69 OP patients have died as a result of their disease. Two-year survival is 76% (63% larynx v 83% OP). CONCLUSION: A high organ preservation rate was obtained with this regimen for OP but not for larynx patients. Toxicity was low, and induction chemotherapy did not preclude delivery of concurrent chemoradiotherapy.

Randomized phase II trial of paclitaxel plus carboplatin or gemcitabine plus cisplatin in Eastern Cooperative Oncology Group performance status 2 non-small-cell lung cancer patients: ECOG 1599.

PURPOSE: Appropriate therapy for Eastern Cooperative Oncology Group (ECOG) performance status (PS) -2 patients with advanced non-small-cell lung cancer (NSCLC) remains challenging. PS-2 patients on ECOG 1594 had a median survival (MS) of only 4.1 months and 1-year overall survival (OS) of 19%. Three percent had grade 5 toxicity. PATIENTS AND METHODS: ECOG 1599, the first PS 2-specific, US cooperative group trial for treatment-naïve advanced NSCLC, randomly assigned patients to dose-attenuated carboplatin/paclitaxel (the least toxic regimen in ECOG 1594) or gemcitabine/cisplatin (which yielded an MS of 7.9 months in PS-2 patients). Patients received either carboplatin (area under the concentration-time curve, 6) and paclitaxel 200 mg/m2 every 3 weeks (CbP) or gemcitabine 1 g/m2 days 1 and 8 and cisplatin 60 mg/m2 day 1 every 3 weeks (CG). RESULTS: One hundred three patients were enrolled; 100 proved eligible. Median age was 66 years; 46% had at least 5% weight loss; 88% had stage IV or recurrent disease. Median number of cycles administered was three per arm. CbP featured more grade 3 neutropathy (10% v 0%) and more grade > or = 3 neutropenia (59% v 33%), whereas CG yielded more grade 3 thrombocytopenia (33% v 14%), more grade 3 fatigue (22% v 14%), and more grade > or = 1 creatinine elevations (43% v 6%). One grade 5 toxicity, confined to the CbP arm, occurred. Response rate, time to progression, MS, and 1-year OS rates for CG and CbP, were 23%, 4.8 months, 6.9 months, and 25%, and 14%, 4.2 months, 6.2 months, and 19%, respectively. CONCLUSION: Platinum-based combination chemotherapy for PS-2 patients with NSCLC is feasible with acceptable toxicity, but survival in these patients remains inferior to that of PS-0 to -1 patients.

Immunohistochemical analysis of C/EBPalpha in non-small cell lung cancer reveals frequent down-regulation in stage II and IIIA tumors: a correlative study of E3590.

PURPOSE: We sought to determine the association of C/EBPalpha expression status with clinical, pathologic and molecular characteristics, as well as outcomes, in non-small-cell lung cancer (NSCLC). This is the first comprehensive study of this transcription factor in patients with NSCLC. PATIENTS AND METHODS: Our cohort originated from ECOG 3590 (randomized trial of postoperative adjuvant therapy with thoracic radiation or cisplatin and etoposide plus thoracic radiation in patients with completely resected stages II and IIIA NSCLC; and its laboratory correlate, ECOG 4592). One hundred and sixty four tumor samples contained sufficient material for immunohistochemical (IHC) analysis. C/EBPalpha tumor staining was compared to that of basal bronchial cells (3+). 0 or 1+ (weak) suggested lack of, while 2 or 3+ (strong) suggested C/EBPalpha expression. RESULTS: Ninety tumors (55%) had 0 or 1+ C/EBPalpha staining, and the remaining 74 (45%) 2 or 3+. Patients with squamous cell carcinomas had a higher percentage of weak C/EBPalpha IHC staining compared to other histologies (p=0.048) and there was a trend for loss of C/EBPalpha in poorly differentiated compared to well differentiated tumors (p=0.07). There was no association between C/EBPalpha IHC and mutations in p53 or K-ras. The median disease-free survival for patients with weak and strong C/EBPalpha IHC expression was 29.6 and 30.6 months, respectively (p=0.94). The median overall survival between the weak and strong groups was 43.5 and 38.5 months, respectively (p=0.83). CONCLUSIONS: Loss of expression of C/EBPalpha is seen in over half of stage II and IIIA NSCLC, specifically in squamous cell carcinomas and poorly differentiated tumors. Since down-regulation of C/EBPalpha is a common event in NSCLC, further elucidation of the involvement of C/EBPalpha in the pathogenesis and progression of lung cancer may identify novel therapeutic targets.

Differential epitope mapping of antibodies to PDC-E2 in patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation and primary biliary cirrhosis.

A unique characteristic of the autoimmune liver disease primary biliary cirrhosis (PBC) is the presence of high-titer and extremely specific autoantibodies to the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Autoantibodies to PDC-E2 antigen have only been detected in patients with disease or in those who subsequently develop PBC. One exception has been a subgroup of patients with multiple myeloma (MM) who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and received donor lymphocyte infusions (DLIs) after transplantation. These patients developed high-titer antibodies to a variety of myeloma-associated antigens, including PDC-E2, coincident with rejection of myeloma cells in vivo. To examine the specificity of autoantibodies to PDC in these patients, we screened sera from patients with MM, chronic leukemias, monoclonal gammopathy of unknown significance (MGUS), PBC, and healthy donors. Three of 11 patients with MM (27%) and 2 of 6 patients with chronic leukemias (33%) developed anti-PDC-E2 antibodies in association with DLI response; 2 of 12 (17%) patients in the MGUS pretreatment control population also had detectable anti-PDC responses. Interestingly, the epitope specificity of these PDC-E2 autoantibodies was distinctive, suggesting that the mechanisms leading to loss of tolerance in the transplantation patients are distinct from PBC.

Long-term outcome and mortality trends in early-stage, Grade 1-2 follicular lymphoma treated with radiation therapy.

PURPOSE: To analyze long-term outcomes and causes of death in patients receiving radiation therapy (RT) for localized, low-grade follicular lymphoma. METHODS AND MATERIALS: Between 1972 and 2000, 106 patients with Stage I-II, Grade 1-2 follicular lymphoma received RT alone or radiation and chemotherapy (RT/CT). Seventy-four percent had Stage I, and 26% had Stage II disease. Seventy-six percent received RT alone, and 24% received combined RT/CT. Second malignancy rates were compared with an age- and sex-matched population. RESULTS: Median follow-up was 12 years. Median survival time was 19 years. The 5-, 10-, and 15-year overall survival (OS) rates were 93%, 75%, and 62%, respectively. Age > or = 60 was the only significant adverse prognostic factor with respect to OS. There were 35 deaths, 20 of which were attributable to lymphoma. Freedom from treatment failure (FFTF) rates at 5, 10, and 15 years were 72%, 46%, and 39%, respectively. Forty-seven patients (48%) relapsed. Tumor size > 3 cm was the only significant adverse factor for FFTF. Observed incidence of second malignancy did not significantly exceed expected incidence. CONCLUSIONS: Although patients with early-stage, low-grade follicular lymphoma have long median survival, the leading cause of death remains lymphoma. However, patients receiving RT do not have significantly elevated cumulative incidence of second malignancy.

Ocular toxicity during adjuvant chemoendocrine therapy for early breast cancer: results from International Breast Cancer Study Group trials.

BACKGROUND: Others have reported ocular toxicity after adjuvant chemoendocrine therapy, but this study looked at ocular toxicity in similarly treated patients from large randomized clinical trials. METHODS: Information was retrieved on incidence and timing of ocular toxicity from the International Breast Cancer Study Group (IBCSG) database of 4948 eligible patients randomized to receive tamoxifen or toremifene alone or in combination with chemotherapy (either concurrently or sequentially). Case reports of patients with ocular toxicity were evaluated to determine whether ocular toxicity occurred during chemotherapy and/or hormonal therapy. Additional information was obtained from participating institutions for patients in whom ocular toxicity occurred after chemotherapy but during administration of tamoxifen or toremifene. RESULTS: Ocular toxicity was reported in 538 of 4948 (10.9%) patients during adjuvant treatment, mainly during chemotherapy. Forty-five of 4948 (0.9%) patients had ocular toxicity during hormone therapy alone, but only 30 (0.6%) patients had ocular toxicity reported either without receiving any chemotherapy or beyond 3 months after completing chemotherapy and, thus, possibly related to tamoxifen or toremifene. In 3 cases, retinal alterations, without typical aspects of tamoxifen toxicity, were reported; 4 patients had cataract (2 bilateral), 12 impaired visual acuity, 10 ocular irritation, 1 optical neuritis, and the rest had other symptoms. CONCLUSION: Ocular toxicity during adjuvant therapy is a common side effect mainly represented by irritative symptoms due to chemotherapy. By contrast, ocular toxicity during hormonal therapy is rare and does not appear to justify a regular program of ocular examination. However, patients should be informed of this rare side effect so that they may seek prompt ophthalmic evaluation for ocular complaints.

A phase II trial of carboplatin and gemcitabine with exisulind (IND #65,056) in patients with advanced non-small cell lung cancer: an Eastern Cooperative Oncology Group study (E1501).

BACKGROUND: Carboplatin and gemcitabine are one standard regimen for patients with advanced non-small cell lung cancer (NSCLC). The oral proapoptotic agent exisulind is a cyclic guanosine monophosphate phosphodiesterase that increases apoptosis in vitro. We performed a phase II trial of carboplatin and gemcitabine with exisulind in patients with advanced NSCLC. METHODS: Gemcitabine (1000 mg/m days 1 and 8) and carboplatin (AUC = 5 day 1) were administered every 21 days, with exisulind orally at 250 mg orally twice daily continuously, starting day 1. The primary objective was to evaluate the 18-month survival. Secondary objectives included response rate, progression-free survival, and toxicities. Eligibility included stage IIIB (pleural effusion) or stage IV NSCLC, no previous chemotherapy, and an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-1. RESULTS: Of 57 eligible patients treated, 34 patients were male and 23 female, 42 had stage IV, six stage IIIB, and nine had recurrent disease. The median age was 63 years (range, 37-83). Twenty-six patients had an ECOG PS of 0 and 31 had a PS of 1. The majority of grade 3-4 toxicities were hematologic. Grade 3-4 nonhematologic toxicity seen in >5% of patients included nausea/vomiting in 16% and fatigue in 23% of patients. The overall response rate was 19.3%. Median progression-free survival was 4.7 months. Median overall survival was 9.0 months. Eighteen-month overall survival was 30%. CONCLUSION: The chemotherapy combination of gemcitabine and carboplatin with the oral proapoptotic agent exisulind is generally well tolerated with principally hematologic toxicity. The statistical endpoint of 17 patients alive at 18 months was met, but given ongoing developments in advanced NSCLC, ECOG will not be pursuing additional trials of exisulind in NSCLC.

Relation between chemotherapy dose, oestrogen receptor expression, and body-mass index.

Clinicians often reduce chemotherapy doses when treating obese patients because of concerns about overdosing. We assessed dose-response according to body-mass index (BMI) and oestrogen receptor (ER) expression of the primary tumour in premenopausal patients with node-positive breast cancer treated with classical CMF (cyclophosphamide, methotrexate, and 5-fluorouracil). Obese patients were significantly more likely to receive a lower chemotherapy dose (<85% of expected dose) for the first course than were those with normal or intermediate BMI (39%vs 16%, p<0.0001). For obese patients and for the total population, reducing the dose of chemotherapy was associated with a significantly worse outcome for the ER-negative cohort (total population hazards ratio 85%vs <85% 0.68 [95% CI 0.54-0.86] for disease free survival; 0.72 [0.56-0.94] for overall survival) but not for the ER-positive cohort (1.16 [0.97-1.40] for disease-free survival; 1.16 [0.94-1.44] for overall survival) [interaction p values=0.0001 for disease-free survival and 0.0019 for overall survival]. Our findings suggest that for women with ER-absent or ER-low tumours, reduction in chemotherapy dose should be avoided.

Radiation therapy for orbital lymphoma.

PURPOSE: To describe radiation techniques and evaluate outcomes for orbital lymphoma. METHODS AND MATERIALS: Forty-six patients (and 62 eyes) with orbital lymphoma treated with radiotherapy between 1987 and 2003 were included. The majority had mucosa-associated lymphoid tissue (48%) or follicular (30%) lymphoma. Seventeen patients had prior lymphoma at other sites, and 29 had primary orbital lymphoma. Median follow-up was 46 months. RESULTS: The median dose was 30.6 Gy; one-third received <30 Gy. Electrons were used in 9 eyes with disease confined to the conjunctiva or eyelid, and photons in 53 eyes with involvement of intraorbital tissues to cover entire orbit. Local control rate was 98% for all patients and 100% for those with indolent lymphoma. Three of the 26 patients with localized primary lymphoma failed distantly, resulting in a 5-year freedom-from-distant-relapse rate of 89%. The 5-year disease-specific and overall survival rates were 95% and 88%, respectively. Late toxicity was mainly cataract formation in patients who received radiation without lens block. CONCLUSIONS: A dose of 30 Gy is sufficient for indolent orbital lymphoma. Distant relapse rate in patients with localized orbital lymphoma was lower than that reported for low-grade lymphoma presenting in other sites. Orbital radiotherapy can be used for salvage of recurrent indolent lymphoma.

Oral fludarabine has significant activity in patients with previously untreated chronic lymphocytic leukemia, and leads to increased STAT1 levels in vivo.

Fifteen patients with previously untreated chronic lymphocytic leukemia (CLL) were treated with oral fludarabine. Toxicities were mainly hematologic, and the response rate was 80%. To assess the effect of fludarabine on the transcription factor STAT1, blood samples obtained on study entry were treated in vitro with fludarabine for 24 h, and the majority of samples displayed an expected decrease in STAT1. To determine whether similar changes occurred in vivo, we developed a flow cytometric assay to quantitate STAT1 levels. On completion of fludarabine cycle 1, CLL cells showed increased STAT1 in the majority of patients, in contrast to the in vitro findings. This may reflect a survival advantage for cells that express high levels of STAT1. In conclusion, oral fludarabine is highly active and merits further investigation in previously untreated patients with CLL. Larger studies are indicated to determine optimal timing of STAT1 assessment, and if changes in STAT1 represent an in vivo indicator of response to purine analog therapy.

A randomized phase II trial of amifostine for head and neck irradiation in lymphoma.

Acute and long-term oral complications occur in patients receiving mantle radiation therapy or irradiation to the head and neck region for Hodgkin's disease or non-Hodgkin's lymphoma. While considerable data are available on the effect of radiation therapy on the oral function and quality of life of patients with squamous cell carcinoma of the head and neck, such information is lacking for similarly irradiated lymphoma patients. In this article we discuss the rationale and study design of an ongoing, randomized phase II study evaluating the role of amifostine (Ethyol; Medimmune Inc, Gaithersburg, MD) as a radiation protectant in patients receiving head and neck irradiation for lymphoma. Further investigation in this lymphoma population is needed to improve our understanding of the extent of the problem and its impact on patients' daily living and functioning. Importantly, fine-tuning the treatment and management approaches to minimize morbidity while maximizing the survival and quality of life of patients are crucial next steps.

The molecular signature of mediastinal large B-cell lymphoma differs from that of other diffuse large B-cell lymphomas and shares features with classical Hodgkin lymphoma.

Mediastinal large B-cell lymphoma (MLBCL) is a recently identified subtype of diffuse large B-cell lymphoma (DLBCL) that characteristically presents as localized tumors in young female patients. Although MLBCL has distinctive pathologic features, it clinically resembles the nodular sclerosis subtype of classical Hodgkin lymphoma (cHL). To elucidate the molecular features of MLBCL, we compared the gene expression profiles of newly diagnosed MLBCL and DLBCL and developed a classifier of these diseases. MLBCLs had low levels of expression of multiple components of the B-cell receptor signaling cascade, a profile resembling that of Reed-Sternberg cells of cHL. Like cHLs, MLBCLs also had high levels of expression of the interleukin-13 (IL-13) receptor and downstream effectors of IL-13 signaling (Janus kinase-2 [JAK2] and signal transducer and activator of transcription-1 [STAT1]), tumor necrosis factor (TNF) family members, and TNF receptor-associated factor-1 (TRAF1). Increased expression of STAT1 and TRAF1 in MLBCL was confirmed by immunohistochemistry. Given the TRAF1 expression and known link to nuclear factor-kappa B (NF- kappa B), MLBCLs were also evaluated for nuclear translocation of c-REL protein. In almost all cases, c-REL was localized to the nucleus, consistent with activation of the NF-kappa B pathway. These studies identify a molecular link between MLBCL and cHL and a shared survival pathway.

Hodgkin's disease in elderly patients (> or =60): clinical outcome and treatment strategies.

PURPOSE: Older age is an adverse prognostic factor for survival for patients with Hodgkin's disease. This study assessed the outcome of elderly patients (>or=60 years) with Hodgkin's disease treated with curative intent in an attempt to identify the optimal treatment strategies for this group of patients. METHODS AND MATERIALS: Eighty-six patients, 60-93 years old at the time of diagnosis, were treated for Hodgkin's disease with radical intent between 1969 and 1995. All patients underwent radiographic staging of the chest, abdomen, and pelvis, and 17 patients underwent staging laparotomy. Fifty-two patients had early-stage disease (Stage IA-IIA) and 34 had Stage IIB-IV Hodgkin's disease. The median follow-up time was 75 months (range 24-267) for surviving patients. RESULTS: The 10-year actuarial freedom from treatment failure (FFTF) rate for all patients was 62%. The 10-year FFTF rate for patients with Stage IA-IIA and Stage IIB-IV disease was 71% and 49%, respectively (p = 0.03). Patients with early-stage disease treated with chemoradiotherapy had a lower crude rate of treatment failure (20%) than patients treated with either chemotherapy alone (33%) or radiotherapy alone (46%). However, no statistically significant difference was found between the treatment groups in terms of actuarial FFTF or overall survival. The 5- and 10-year overall survival rate (all causes) for all patients was 48% and 30%, respectively. The 10-year survival rate for patients with Stage IA-IIA and Stage IIB-IV disease was 31% and 26%, respectively (p = 0.07). On multiple regression analysis, including age, treatment, and stage in the Cox regression model with respect to overall survival, age was a marginally significant factor (p = 0.08). For FFTF, age was not a significant factor in the model (p = 0.11). We analyzed the subsequent outcome of patients who developed a first recurrence after initial treatment; the 5-year survival rate was only 20% after recurrence of Hodgkin's disease. Initial treatment was reasonably well tolerated. CONCLUSION: Although more patients died of other causes than Hodgkin's disease, the recurrence of Hodgkin's disease had a significant impact on survival. Thus, we favor the use of chemoradiotherapy in early-stage patients >60 years to minimize the risk of relapse.

The vascular endothelial growth factor receptor tyrosine kinase inhibitor PTK787/ZK222584 inhibits growth and migration of multiple myeloma cells in the bone marrow microenvironment.

Our prior studies show that multiple myeloma (MM) cell lines and patient cells express high-affinity vascular endothelial growth factor (VEGF) receptor (VEGFR) Flt-1 but not Flk-1/KDR. Moreover, these studies have shown that VEGF induces proliferation and migration of MM cells, and we have begun to delineate the signaling cascades mediating those sequelae. In this study, we examined the activity of PTK787/ZK 222584 (PTK787), a molecule designed to bind specifically to the tyrosine kinase domain of VEGFR and inhibit angiogenesis. We show that PTK787 acts both directly on MM cells and in the bone marrow microenvironment. Specifically, PTK787 (1-5 micro M) inhibits proliferation of MM cells by 50%, as assayed by [(3)H]thymidine uptake. This effect of PTK787 is dose dependent in both MM cell lines and patient cells that are both sensitive and resistant to conventional therapy. PTK787 enhances the inhibitory effect of dexamethasone on growth of MM cells and can overcome the protective effect of interleukin 6 (IL-6) against dexamethasone-induced apoptosis. PTK787 (1 micro M) also blocks VEGF-induced migration of MM cells across an extracellular matrix. Importantly, PTK787 also inhibits the increased MM cell proliferation and increased IL-6 and VEGF secretion in cultures of MM cells adherent to bone marrow stem cells. These findings therefore demonstrate that PTK787 both acts directly on MM cells and inhibits paracrine IL-6-mediated MM cell growth in the bone marrow milieu. The demonstrated anti-MM activity of PTK787, coupled with its antiangiogenic effects, provides the framework for clinical trials of this agent to overcome drug resistance and improve outcome in MM.