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Biomedical subjects

Asher Chanan-Khan

Publications and source records attributed to Asher Chanan-Khan.

At least 19 recordsLinked to original sources
PubMed2006

Clinical efficacy of lenalidomide in patients with relapsed or refractory chronic lymphocytic leukemia: results of a phase II study.

PURPOSE: Patients with relapsed or refractory chronic lymphocytic leukemia (CLL) have profound immune defects and limited treatment options. Given the dramatic activity of lenalidomide in other B-cell malignancies and its pleotropic immunomodulatory effects, we conducted a phase II trial of this agent in CLL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell CLL (B-CLL) were eligible if they required treatment as per the National Cancer Institute Working Group 1996 guidelines. Lenalidomide was administered orally at 25 mg on days 1 through 21 of a 28-day cycle. Response was assessed after each cycle. Patients were to continue treatment until disease progression, unacceptable toxicity, or complete remission. Rituximab was added to lenalidomide on disease progression. RESULTS: Forty-five patients were enrolled, with a median age of 64 years. Sixty-four percent of the patients had Rai stage III or IV disease, and 51% were refractory to fludarabine. The overall response rate was 47%, with 9% of the patients attaining a complete remission. Fatigue, thrombocytopenia, and neutropenia were the most common adverse effects noted in 83%, 78%, and 78% of the patients, respectively. CONCLUSION: Lenalidomide is clinically active in patients with relapsed or refractory B-CLL. These findings are encouraging and warrant further investigation of this agent in the treatment of this disorder.

Adult↗
PubMed2006

Regular analgesic use and risk of multiple myeloma.

Analgesic use has been implicated in the chemoprevention of a number of solid tumors, but to date no previous research has focused on the role of analgesics in the etiology of multiple myeloma (MM). We conducted a hospital-based case-control study of 117 patients with primary, incident MM and 483 age and residence matched controls without benign or malignant neoplasms. All participants received medical services at Roswell Park Cancer Institute in Buffalo, NY, and completed a comprehensive epidemiological questionnaire. Participants who reported analgesic use at least once a week for at least 6 months were classified as regular users; individuals who did not use analgesics regularly served as the reference group throughout the analyses. We used unconditional logistic regression analyses to compute crude and adjusted odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Compared to non-users, regular aspirin users were not at reduced risk of MM (adjusted OR=0.99; 95% CI 0.65-1.49), nor were participants with the highest frequency or duration of aspirin use. A significant risk elevation was found for participants who were regular acetaminophen users (adjusted OR=2.95; 95% CI 1.72-5.08). Further, marked increases in risk of MM were noted with both greater frequency (>7 tablets weekly; adjusted OR=4.36; 95% CI 1.70-11.2) and greater duration (>10 years; adjusted OR=3.26; 95% CI 1.52-7.02) of acetaminophen use. We observed no evidence of a chemoprotective effect of aspirin on MM risk, but observed significant risk elevations with various measures of acetaminophen use. Our results warrant further investigation in population-based case-control and cohort studies and should be interpreted with caution in light of the limited sample size and biases inherent in hospital-based studies.

Acetaminophen↗
PubMed2006

The combination of the proteasome inhibitor bortezomib and the bcl-2 antisense molecule oblimersen sensitizes human B-cell lymphomas to cyclophosphamide.

PURPOSE: To determine whether the combination of the proteasome inhibitor bortezomib and the bcl-2 antisense molecule oblimersen can sensitize human lymphoma to cyclophosphamide. EXPERIMENTAL DESIGN: Cytotoxicity assays were conducted to determine if there was any additive or synergistic interaction between the combinations of bortezomib, oblimersen, and cyclophosphamide using a standard trypan blue exclusion assay. Based on these experiments, in vivo experiments in severe combined immunodeficiency beige mice were done using human lymphoma xenografts in which different schedules were explored. Bcl-2 and oblimersen levels were determined in treated tumors, some of which were resected at the end of the in vivo experiment and evaluated pathologically. RESULTS: The results suggest that the combination of bortezomib and oblimersen seem to interact in at least an additive fashion, and that the addition of cyclophosphamide to this drug combination can markedly improve tumor cell kill. In addition, it seems that these drug combinations may be schedule-dependent, with a requirement for oblimersen pretreatment. Animals treated with the triplet drug combination in a schedule-dependent manner experienced pathologic complete regression of disease, which was not observed in other treatment cohorts. The addition of bortezomib also seemed to increase the levels of intracellular oblimersen, which resulted in a marked reduction in Bcl-2. Histologic studies confirmed marked necrosis and caspase-3 activation only in the cohort receiving all three drugs. CONCLUSION: The use of Bcl-2-directed therapy and a proteasome inhibitor sensitizes human lymphoma cells to cytotoxic drugs like cyclophosphamide. This combination may offer new opportunities for integrating novel targeted therapies with conventional chemotherapy.

Animals↗
PubMed2006

Immunomodulating drugs for chronic lymphocytic leukaemia.

Chronic lymphocytic leukaemia (CLL) is a malignant haematological disorder that remains mostly incurable; more than 95% of patients have disease of B-cell origin. Advances with targeted agents such as monoclonal antibodies, antisense therapy, or both these techniques combined with traditional chemotherapy have improved the frequency of remission. The clinical course of CLL is marked by frequent relapse, and there are limited therapeutic options for patients with relapsed or refractory disease. The morphologically mature CLL clone regulates the microenvironment through modulation of the cytokine milieu that aids its growth and survival, and has a role in immune escape. Targeting of the tumour-cell microenvironment has not been investigated as a treatment option for CLL. Immunomodulating agents are a new class of drugs that change expression of various cytokines and that costimulate immune effector cells.

Aged↗
PubMed2006

Prospective evaluation of low-dose warfarin for prevention of thalidomide associated venous thromboembolism.

Venous thromboemobolism (VTE) is an important complication of thalidomide therapy especially when it is combined with steroids or chemotherapy. Currently there is no consensus on the most appropriate prophylactic approach. We prospectively investigated the use of low-dose warfarin sodium in prevention of thalidomide-associated VTE in patients receiving thalidomide-based combination therapies. Patients with multiple myeloma or chronic lymphocytic leukemia who were treated on thalidomide based-combination therapies were treated on low-dose warfarin (1 or 2 mg) continuously through the duration of their therapy. Among the 68 patients enrolled, four developed an episode of VTE, an overall incidence of 5.9% (odds = 0.063). Median duration of thalidomide therapy was 4 months. Low-does warfarin decreases the incidence of VTE compared to historical control and is an effective mechanism of prevention of VTE in thalidomide-based chemotherapy regimens.

Aged↗
PubMed2006

Supportive care in multiple myeloma.

Significant progress in the treatment of multiple myeloma has resulted in improvement of disease control with a trend toward overall and progression-free survival benefit. With the availability of several new therapeutic agents and combinations, a careful emphasis should be placed in the management of disease- and therapy-associated complications. Aggressive management of these complications can impact patients' quality of life as well as treatment outcome. This review highlights some of the critical supportive care measures integral to the optimal care of patients with multiple myeloma.

Anemia↗
PubMed2005

Results of a phase 1 clinical trial of thalidomide in combination with fludarabine as initial therapy for patients with treatment-requiring chronic lymphocytic leukemia (CLL).

Tumor necrosis factor alpha (TNF-alpha) and vascular endothelial growth factor (VEGF) play an important role in the biology of chronic lymphocytic leukemia (CLL) cells. Thalidomide is a first-generation immuno-modulating agent that down-regulates TNF-alpha and VEGF. We initiated a phase 1/2 clinical trial to determine the safety and efficacy of combining thalidomide with fludarabine in patients with treatment-naïve CLL. Patients received 6 months of continuous daily thalidomide with standard monthly doses of fludarabine. Three dose levels of thalidomide (100, 200, and 300 mg) were studied. Results from the phase 1 part of this study are reported here. Thirteen patients were enrolled in the phase 1 component of the study. Dose-limiting toxicity was not reached. The most common toxicities noted were fatigue, constipation, and peripheral sensory neuropathy. Overall response rate was 100% with 55% of patients achieving complete remissions. At a median follow-up of 15+ months none of the patients have had a relapse and the median time to disease progression has not yet been reached. Responses were noted at all dose levels. Thalidomide given up to 300 mg/day concurrently with fludarabine in patients with previously untreated CLL shows encouraging clinical efficacy and acceptable toxicity. An ongoing phase 2 part of this study will help validate the clinical efficacy of this regimen.

Antineoplastic Agents↗
PubMed2005

Bcl-2 antisense therapy in B-cell malignancies.

Bcl-2 is an apoptosis regulating protein, overexpression of which is associated with chemotherapy resistant disease, aggressive clinical course, and poor survival in patients with B-cell lymphoproliferative disorders. Overexpression of Bcl-2 protein results in an aberrant intrinsic apoptotic pathway that confers a protective effect on malignant cells against a death signal (e.g., chemotherapy or radiotherapy). Downregulation of this oncoprotein, thus, represents a possible new way to target clinically aggressive disease. Preclinical studies have shown that this oncoprotein can be effectively decreased by Bcl-2 antisense in malignant lymphoid cells and can reverse chemotherapy resistance, as well as enhance the anti-apoptotic potential of both chemotherapeutic and biologic agents. Ongoing clinical trials are exploring the role of Bcl-2 downregulation with oblimersen (Bcl-2 antisense) in patients with non-Hodgkin's lymphoma, chronic lymphocytic leukemia and multiple myeloma. Early results from these studies are promising and support the proof of the principle. As these studies are completed and mature data emerges, the role of Bcl-2 antisense therapy in the treatment of B-cell malignancies will become clearer.

Antineoplastic Agents↗
PubMed2005

Arterial thrombosis in four patients treated with thalidomide.

Thalidomide has been associated with venous thrombotic events, as reported in the post-marketing surveillance reports by Celgene Corporation; as well as case reports in the literature. Seven arterial thrombotic events have been reported in patients receiving thalidomide with 3 cases occurring in patients with other predisposing conditions. We report 4 additional cases of arterial thromboses in 1 lymphoma and 3 myeloma patients treated with thalidomide. The mechanism for these events is unclear; however, it is significant that 2 patients were receiving concomitant anticoagulation with aspirin and warfarin.

Aged↗
PubMed2005

Non-Hodgkin's lymphoma presenting as a breast mass in patients with HIV infection: a report of three cases.

Breast involvement with non-Hodgkin's lymphoma (NHL) is rare. Patients with AIDS have an increased incidence of NHL, often with high-grade histology, extranodal presentation and aggressive clinical course. Lymphoma of the breast in patients with HIV-1 infection has not been reported. We reviewed our tumor registry database of all AIDS-associated NHL and report on the clinical presentation and long-term outcome of 3 patients with AIDS who presented with lymphomatous involvement of the breast.

Adult↗
PubMed2004

Bcl-2 antisense therapy in B-cell malignant proliferative disorders.

Overexpression of Bcl-2 oncogene has been clinically associated with an aggressive clinical course, chemotherapy and radiotherapy resistance, and poor survival in patients with malignant B-cell disorders. Patients with relapsed or refractory chronic lymphocytic leukemia, multiple myeloma, or non-Hodgkin's lymphoma have limited therapeutic options. Preclinical and early clinical data have shown that Bcl-2 oncoprotein can be decreased by Bcl-2 antisense therapy. Also, downregulation of Bcl-2 protein can result in reversal of chemotherapy resistance and improved antitumor activity of biologic agents. Various clinical trials are evaluating the role of targeting Bcl-2 as a mechanism to enhance the antitumor potential of chemotherapy and immunotherapy. Early results from these clinical studies are encouraging and confirm the proof of principle for antisense therapy. As current data mature, these trials will hopefully validate preliminary results and establish Bcl-2 antisense as an important addition to the current armamentarium used in the treatment of patients with B-cell neoplasms.

Biomarkers, Tumor↗
PubMed2004

Long-term survival with allogeneic stem cell transplant and donor lymphocyte infusion following salvage therapy with anti-CD52 monoclonal antibody (Campath) in a patient with alpha/beta hepatosplenic T-cell non-Hodgkin's lymphoma.

Hepatosplenic T-cell non-Hodgkin's lymphoma (HSTCL) is a rare, aggressive form of NHL, with a median survival of approximately 8 months. We were able to successfully induce complete remission in a patient with alpha/beta HSTCL who was refractory to multiple prior chemotherapy regimens, using the humanized anti-CD52 monoclonal antibody alemtuzumab (Campath). Once disease was controlled, the patient was able to undergo allogeneic stem cell transplantation (SCT), which resulted in complete remission. Furthermore, upon relapse, we were able to re-induce complete clinical and molecular remission with donor lymphocyte infusions. At Day 655 (post-SCT), the patient remains in complete remission. These data suggest a potential role for alemtuzumab and allogeneic SCT in the treatment of T-cell NHL.

Adult↗
PubMed2004

Bcl-2 antisense therapy in hematologic malignancies.

PURPOSE OF REVIEW: Overexpression of the Bcl-2 oncoprotein is noted in various malignant disorders. In patients with hematologic malignancies, increased production of the Bcl-2 oncoprotein is associated with chemotherapy resistance, aggressive clinical course, and poor survival. Bcl-2 is an important molecular target. Downregulating Bcl-2 can potentially reverse inherent tumor resistance to, and possibly improve response to therapy. This review focuses on the preclinical data, as well as the current clinical information available on oblimersen, a novel antisense approach targeting Bcl-2 in malignant hematologic disorders. RECENT FINDINGS: Early clinical trials have shown single-agent activity of oblimersen in patients with chronic lymphocytic leukemia and non-Hodgkin lymphoma, and thus, provide proof of principle for antisense therapy. Phase I and phase II studies using oblimersen in combination with conventional chemotherapy have shown encouraging results in patients with non-Hodgkin lymphoma, chronic lymphocytic leukemia, and acute myeloid leukemia. Phase III studies in patients with multiple myeloma and chronic lymphocytic leukemia have completed accrual and results are awaited. SUMMARY: Bcl-2 is a clinically meaningful target in patients with hematologic malignancies. Downregulation of the Bcl-2 oncoprotein can be achieved with oblimersen (antisense molecule specific for Bcl-2). Early clinical results suggest a possible role of this antisense approach in targeting Bcl-2. Ongoing clinical trials will establish the clinical utility of oblimersen in patients with hematologic malignancies.

Antineoplastic Agents↗
PubMed2004

Pro-apoptotic therapy with the oligonucleotide Genasense (oblimersen sodium) targeting Bcl-2 protein expression enhances the biological anti-tumour activity of rituximab.

New strategies have evolved in the treatment of patients with non-Hodgkin's lymphoma (NHL). Anti-sense oligonucleotides (ASO) and monoclonal antibody (mAb) therapy, though proven to be safe and effective, have not demonstrated to be curative when used as single agents. We tested an innovative combination strategy involving various mAbs and ASO against Bcl-2 (G3139) in aggressive preclinical models. G3139, under optimal transfection conditions, decreased the proliferation rate of lymphoma cells by 60-75% when compared with controls. In addition, apoptosis was demonstrated in Raji (25%) and DHL-4 cells (30%) treated with Genasense following downregulation of Bcl-2 protein. Downregulation of Bcl-2 by G3139 was associated with a higher degree of rituximab-associated, complement-mediated cytotoxicity and antibody dependent cellular cytotoxicity when compared with rituximab alone-treated controls. In vivo studies in severe combined immunodeficiency (SCID) mice clearly demonstrated synergistic activity between G3139 and rituximab. Treatment of lymphoma-bearing SCID mice with G3139 for two consecutive days prior to each rituximab dose resulted in better disease control and survival than treatment with either agent alone or controls. Our findings suggest that Bcl-2 downregulation by G3139, followed by the administration of rituximab is an efficient anti-tumour strategy associated with improved survival in lymphoma-bearing SCID mice.

Animals↗
PubMed2003

T-cell clonality and myelodysplasia without chromosomal fragility in a patient with features of Seckel syndrome.

Seckel syndrome is a rare autosomal recessive disorder with characteristic craniofacial dysmorphism, skeletal defects, mental and prenatal growth retardation. About 50 cases have been reported in the literature. Hematologic abnormalities with associated chromosomal fragility have been noted in about 15% of the reported cases. We report a patient with Seckel syndrome with myelodysplastic features and clonal T-cells in the bone marrow but no evidence of chromosomal fragility. After 5 years of follow-up, this patient remains asymptomatic without any treatment and with stable peripheral blood counts.

Abnormalities, Multiple↗
PubMed2002

A multicenter phase II study of the intravenous administration of liposomal tretinoin in patients with acquired immunodeficiency syndrome-associated Kaposi's sarcoma.

BACKGROUND: A multicenter trial was conducted to determine the efficacy and toxicity of escalating dosages of liposomal tretinoin (all-trans-retinoic acid) administered once or three times weekly in patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma. METHODS: Seventy-six patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma were randomized to receive the study drug either once (n = 30) or 3 times weekly (n = 46). The starting dosage was 60 mg/m(2), which was escalated to 90 mg/m(2) and then 120 mg/m(2) if the drug was well tolerated (<or= Grade 2 toxicities [according to the Southwest Oncology Group toxicity scale]). Four weeks of therapy constituted 1 cycle; patients could receive up to 8 cycles and those who completed 8 cycles were given the option of receiving extended therapy. Clinical response was defined as complete response (CR), partial response (PR), or stable disease (SD). RESULTS: Efficacy was assessed after the completion of 3 treatment cycles; 28.9% of patients (22 of 76 patients) responded (no CRs, 1 PR, and 21 SDs). Among the patients receiving treatment 3 times weekly, 16 of 49 patients (32.7%) achieved a clinical response at the end of the third treatment cycle (no CRs, 1 PR, and 15 SDs). Concomitant or prior use of protease inhibitors did not appear to affect the patient's response to treatment (P = 0.183). CONCLUSIONS: Liposomal tretinoin is a new therapeutic agent that has been reported to have some clinical activity in patients with AIDS-associated Kaposi sarcoma. A three-times-per-week dosing schedule was noted to be more effective compared with a once-a-week schedule without any significant difference in toxicity reported.

Acquired Immunodeficiency Syndrome↗