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Nai-Kong V Cheung

Publications and source records attributed to Nai-Kong V Cheung.

At least 19 recordsLinked to original sources
PubMed2007

High-dose cyclophosphamide inhibition of humoral immune response to murine monoclonal antibody 3F8 in neuroblastoma patients: broad implications for immunotherapy.

BACKGROUND: The murine monoclonal antibody 3F8 mediates lysis of neuroblastoma (NB) by complement and leukocytes (including neutrophils) but is neutralized if human anti-mouse antibody (HAMA) forms. We assessed the impact on rapid HAMA formation of prior chemotherapy in NB patients. METHODS: For the 153 patients treated with 3F8 after conventional therapy (Group 1), the analysis included time from chemotherapy to the start of 3F8. For the 103 patients treated with 3F8 after myeloablative alkylator-based therapy (MAT) (Group 2), the analysis included both chemotherapy administered before stem-cell collection and time from MAT to the start of 3F8. RESULTS: In Group 1, the incidence of HAMA-positivity was significantly lower if patients received high-dose cyclophosphamide (HD-Cy, > or = 4,000 mg/m2) before 3F8 treatment (P < 0.001). In addition, HAMA-positivity was least likely if 3F8 treatment was initiated <90 days post-HD-Cy (2/76 compared to 3/19 first treated at 90-120 days, and 17/27 first treated at >120 days, P < 0.001). In Group 2 patients who were transplanted with stem cells collected after HD-Cy, HAMA-positivity occurred in 1/60 patients treated <90 days post-MAT versus 13/23 treated >90 days post-MAT (P < 0.001). Among Group 2 patients transplanted with stem cells collected after no prior HD-Cy, the incidence of HAMA-positivity was significantly higher (15/19, P < 0.001), including 5/7 whose 3F8 treatment began <90 days post-MAT. CONCLUSIONS: HD-Cy reliably blocks humoral responses to a murine antibody. This capacity to prevent host rejection of foreign or not fully humanized proteins raises the possibility of a broad role for HD-Cy in immunotherapeutic strategies.

Adolescent↗
PubMed2006

Irinotecan plus temozolomide for relapsed or refractory neuroblastoma.

PURPOSE: To report on an irinotecan and temozolomide regimen for neuroblastoma (NB). Quality of life and minimizing toxicity were major considerations. PATIENTS AND METHODS: The plan stipulated 5-day courses of irinotecan 50 mg/m2 (1-hour infusion) and temozolomide 150 mg/m2 (oral) every 3 to 4 weeks, with a pretreatment platelet count more than 30,000/microL. Granulocyte colony-stimulating factor was used when the absolute neutrophil count was less than 1,000/microL. RESULTS: Forty-nine NB patients received 1 to 15 courses (median, 5). Gastrointestinal and myelosuppressive toxicities were readily managed. Lymphocyte responses to phytohemagglutinin after 2 to 10 courses (median, 3.5) were normal in 10 of 10 patients treated after nonimmunosuppressive therapy, and normalized in five of seven patients first treated less than 2 months after high-dose alkylators. Of 19 patients treated for refractory NB and assessable for response, nine showed evidence of disease regression, including two complete responses and seven objective responses. Of 17 patients treated for progressive disease, three showed evidence of disease regression, including one partial response and two objective responses. Multiple courses entailed no cumulative toxicity and controlled disease for prolonged periods in many patients, including some who were unable to complete prior treatments because of hematologic, infectious, cardiac, or renal problems. CONCLUSION: This regimen has anti-NB activity, spares vital organs, is feasible with poor bone marrow reserve, causes limited immunosuppression, and allows good quality of life.

Adolescent↗
PubMed2006

Ototoxicity from high-dose use of platinum compounds in patients with neuroblastoma.

BACKGROUND: The young age of neuroblastoma patients makes them especially prone to the ototoxic effects of widely used treatments that feature aggressive use of platinum compounds. We present data defining the extent of the problem in a large series of neuroblastoma patients whose induction included high-dose cisplatin/etoposide (HD-P/E) as used in both the Memorial Sloan-Kettering Cancer Center N7 regimen and the Children's Oncology Group A3973 study. METHODS: N7/A3973 patients were divided into 3 groups: Group 1 had hearing tested after induction, that included 2 cycles of HD-P/E (cumulative cisplatin = 400 mg/m(2)); Group 2 had hearing tested after induction, that included 3 cycles of HD-P/E (cumulative cisplatin = 600 mg/m(2)); and Group 3 had hearing tested following carboplatin-containing myeloablative therapy administered after induction, that included 2 cycles of HD-P/E. Ototoxicity was scored by the Brock method. RESULTS: All 3 groups had similar clinical characteristics, including median age at diagnosis of about 3 years. Little or no hearing loss in the speech range (Grade 0/1) was documented in 21 (32%) of the 65 Group 1 patients, 5 (10%) of the 50 Group 2 patients, and 9 (15.5%) of the 58 Group 3 patients. Severe (Grade 3/4) deficits affected 25% of Group 1, 54% of Group 2, and 50% of Group 3 patients. Patients < 5 years at diagnosis had greater ototoxicity than older patients had, with adolescents/adults being the least affected. Findings were stable in repeated assessments over 2 or more years. CONCLUSIONS: Ototoxicity is a serious and pervasive problem in this patient population. Strategies to ameliorate ototoxicity without compromising on antitumor activity of treatments are urgently needed.

Antineoplastic Agents↗
PubMed2006

Sialyltransferase STX (ST8SiaII): a novel molecular marker of metastatic neuroblastoma.

Polysialic acid (PSA) is highly expressed in many human cancers, including neuroblastoma (NB), and is critical for cellular adhesion, neuronal migration and tumor metastasis. The key enzyme responsible for PSA synthesis is sialyltransferase STX (ST8SiaII). Using quantitative RT-PCR we (i) studied STX expression in 39 NB tumors and 8 cell lines and (ii) examined its potential clinical utility as an early response marker in the bone marrows of the entire cohort of 136 high-risk NB patients treated with an immunotherapy protocol utilizing anti-GD2 antibody 3F8 and GM-CSF. Based on the quantitation of 24 normal marrow and peripheral blood samples, a normalized STX transcript value below the mean + 2SD was defined as negative. Sensitivity of this assay was 1 NB cell in 10(6) normal mononuclear cells. STX expression was high among NB tumors of all stages, as well as NB cell lines of different phenotypes. Evaluation for early (2.5 months from protocol entry) marrow response by univariate Cox model indicated that STX marker status (positive versus negative) was strongly associated with both progression-free and overall survival (p < 0.0005 for both). Similarly, the STX transcript level of posttreatment marrows was also highly prognostic of outcome (PFS, p = 0.001; OS, p < 0.0005). We conclude that STX mRNA has potential clinical utility as a molecular marker of metastatic NB.

Biomarkers, Tumor↗
PubMed2006

FCGR2A polymorphism is correlated with clinical outcome after immunotherapy of neuroblastoma with anti-GD2 antibody and granulocyte macrophage colony-stimulating factor.

PURPOSE: Anti-GD2 murine IgG3 antibody 3F8 kills neuroblastoma cells by antibody-dependent cell-mediated cytotoxicity (ADCC). Granulocyte macrophage colony-stimulating factor (GM-CSF) enhances phagocyte-mediated ADCC. The differential affinity of the human FCGR polymorphic alleles for 3F8 may influence the effectiveness of antibody immunotherapy. PATIENTS AND METHODS: The entire cohort of high risk neuroblastoma patients (N = 136) treated on protocol using 3F8 and GM-CSF were the subjects of this analysis. Tumor response was measured by standard clinical tools plus sensitive molecular monitoring using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Polymorphic alleles of FCGR2A and FCGR3A were determined by PCR plus direct sequencing using genomic DNA samples obtained from marrow or blood of patients. RESULTS: FCGR2A (R/R) genotype correlated with progression-free survival for the entire cohort (P = .049) and for the subset of patients with no history of prior relapse (P = .023). FCGR2A (R/R) also correlated with marrow remission 2.5 months after treatment initiation: by histology (P = .021 and P = .036, for the entire cohort and the subset, respectively) and by qRT-PCR (P = .052 and P = .033, respectively). CONCLUSION: The favorable outcome associated with FCGR2A (R/R) genotype is consistent with the proposed role of FCGR2A and phagocyte-mediated ADCC in 3F8 plus GM-CSF immunotherapy.

Antibodies, Monoclonal↗
PubMed2006

Liver involvement in neuroblastoma: the Memorial Sloan-Kettering Experience supports treatment reduction in young patients.

BACKGROUND: We reviewed clinical and biologic findings in a series of infants with neuroblastoma (NB) in liver. The aim was to gain insights into improving therapy. PATIENTS AND METHODS: Among 19 newly or recently diagnosed infants with NB in liver, 1987-2002, those with stage 4 involving bone received chemotherapy, while those without bone or extensive bone marrow (BM) involvement were observed or received limited treatment if NB caused life-threatening symptoms. We assessed results in the context of NB treatment risk stratification, which is based on age, stage, and selected biologic features (MYCN, ploidy, histology). RESULTS: Six of eight infants with bone involvement became long-term event-free survivors including 1/2 with MYCN amplification and four who received only 4-6 cycles of chemotherapy; at the end of treatment, four infants had abnormalities in liver +/- the primary site, but these resolved. All 11 infants without bone lesions became long-term survivors with either no cytotoxic therapy or only one cycle of chemotherapy (+/- radiotherapy to liver), including four who had stage 4 and one stage 4S patient who still had NB in BM at age 15 months. CONCLUSIONS: Treatment reduction should be considered for subsets of infants with non-MYCN-amplified widespread NB: stage 4 without bone or extensive BM involvement may not require cytotoxic therapy, stage 4S with symptomatic hepatomegaly may not require multiple cycles of chemotherapy, and classic stage 4 may do well with limited chemotherapy. Persistent liver abnormalities post-treatment may not require continued therapy to achieve a radiologic complete remission.

Bone Marrow Neoplasms↗
PubMed2005

Complement-mediated mechanisms in anti-GD2 monoclonal antibody therapy of murine metastatic cancer.

The role of complement in antibody therapy of cancer is in general poorly understood. We used the EL4 syngeneic mouse model of metastatic lymphoma to investigate the role of complement in immunotherapy directed against GD2, a target of clinical relevance. IgG2a and IgM anti-GD2 therapy protected EL4-challenged mice from metastases and prolonged survival. Expression of CD59, an inhibitor of direct complement-mediated cytotoxicity (CMC), effectively protected EL4 cells from CMC in vitro but did not affect the outcome of monoclonal antibody therapy. Protection by IgG therapy was also unaffected in mice deficient in C3 or complement receptor 3 (CR3) but was almost completely abrogated in FcgammaR I/III-deficient mice. These data indicate a crucial role for antibody-dependent cell-mediated cytoxicity (ADCC). However, at lower doses of IgG, therapeutic effect was partially abrogated in C3-deficient mice, indicating complement-mediated enhancement of ADCC at limiting IgG concentration. In contrast to IgG, the therapeutic effect of IgM was completely abrogated in C3-deficient mice. High level expression of CD59 on EL4 did not influence IgM therapy, suggesting IgM functions by complement-dependent cell-mediated cytotoxicity (CDCC), a mechanism thought to be inactive against tumor cells. Thus, IgG and IgM can operate via different primary mechanisms of action, and CDCC and complement-dependent enhancement of ADCC mechanisms are operative in vivo. The effects of complement can be supplemental to other antibody-mediated mechanisms and likely have increased significance at limiting antibody concentration or low antigen density.

Animals↗
PubMed2005

EMP3, a myelin-related gene located in the critical 19q13.3 region, is epigenetically silenced and exhibits features of a candidate tumor suppressor in glioma and neuroblastoma.

The presence of common genomic deletions in the 19q13 chromosomal region in neuroblastomas and gliomas strongly suggests the presence of a putative tumor suppressor gene for these neoplasms in this region that, despite much effort, has not yet been identified. In an attempt to address this issue, we compared the expression profile of 89 neuroblastoma tumors with that of benign ganglioneuromas by microarray analysis. Probe sets (637 of 62,839) were significantly down-regulated in neuroblastoma tumors, including, most importantly, a gene located at 19q13.3: the epithelial membrane protein 3 (EMP3), a myelin-related gene involved in cell proliferation and cell-cell interactions. We found that EMP3 undergoes hypermethylation-mediated transcriptional silencing in neuroblastoma and glioma cancer cell lines, whereas the use of the demethylating agent 5-aza-2-deoxycytidine restores EMP3 gene expression. Furthermore, the reintroduction of EMP3 into neuroblastoma cell lines displaying methylation-dependent silencing of EMP3 induces tumor suppressor-like features, such as reduced colony formation density and tumor growth in nude mouse xenograft models. Screening a large collection of human primary neuroblastomas (n = 116) and gliomas (n = 41), we observed that EMP3 CpG island hypermethylation was present in 24% and 39% of these tumor types, respectively. Furthermore, the detection of EMP3 hypermethylation in neuroblastoma could be clinically relevant because it was associated with poor survival after the first 2 years of onset of the disease (Kaplan-Meier; P = 0.03) and death of disease (Kendall tau, P = 0.03; r = 0.19). Thus, EMP3 is a good candidate for being the long-sought tumor suppressor gene located at 19q13 in gliomas and neuroblastomas.

Animals↗
PubMed2005

Five-day courses of irinotecan as palliative therapy for patients with neuroblastoma.

BACKGROUND: The authors describe a large experience using short courses of irinotecan for palliative therapy in patients with neuroblastoma (NB). Quality of life was a major issue in choosing this regimen for patients whose disease was resistant to standard anti-NB therapies. METHODS: A retrospective review was conducted of all patients who were followed by the Department of Pediatrics at Memorial Sloan-Kettering Cancer Center and treated for resistant NB with irinotecan at 50 mg/m2 per day for 5 days as a 1-hour intravenous infusion. Treatment was outpatient, and there was a minimum 2-week rest period between courses. Granulocyte colony-stimulating factor was used to keep the absolute neutrophil count >500-1000/mL. RESULTS: Forty-four patients had been treated aggressively and/or extensively before they received one or more five-day courses of irinotecan. Emetogenic, diarrheal, and myelosuppressive effects were readily managed. Hospitalizations were limited to three patients with bacteremia. Twenty-three patients had a change in therapy, although they did not have progressive disease (PD) after receiving 1 (n=10), 2 (n=3), 3 (n=1), 4 (n=6), 7 (n=1 patient), 22 (n=1 patient), or 24 (n=1) courses. The most common reasons for changing treatment were to intensify retrieval therapy or to pursue immunotherapy. Of those 23 patients, 15 patients had stable disease, 7 were not evaluable for response because of concurrent radiotherapy, and 1 patient had a major response. Twenty-one patients had PD after 1 (n=3, 2 (n=9), 4 (n=2), 5 (n=1), 6 (n=3), 7 (n=1), 9 (n=1), and 11 (n=1) courses. CONCLUSIONS: In heavily treated patients, the regimen studied was well tolerated, allowed patients to continue most normal life activities, and produced anti-NB effects. Its modest toxicity supported use with other antitumor agents.

Adolescent↗
PubMed2005

Long-term complications in survivors of advanced stage neuroblastoma.

BACKGROUND: Few studies have assessed late effects in neuroblastoma (NB) survivors, particularly those with advanced stage disease. METHODS: Retrospective analysis of a cohort of advanced stage NB survivors followed in a late effect clinic at a single institution. Screening tests to detect late effects were tailored depending on the individual's treatment exposures. RESULTS: The study included 63 survivors (31 males). The median age at diagnosis was 3.0 years. The median follow-up from diagnosis was 7.06 years. All patients had surgery and received chemotherapy, 89% received radiation therapy (RT), 62% immunotherapy, and 56% autologous stem cell transplant. Late complications were detected in 95% of survivors and included: hearing loss (62%), primary hypothyroidism (24%), ovarian failure (41% of females), musculoskeletal (19%), and pulmonary (19%) abnormalities. The majority of complications were moderate, with only 4% being life-threatening. Survivors who received cisplatin were at greater risk to develop hearing loss compared to those not so treated (OR 9.74; 95% CI: 0.9-101.6). A total dose of cyclophosphamide greater than 7.4 g was associated with ovarian failure (P = 0.02). CONCLUSIONS: Late complications occur frequently in survivors of advanced stage NB. The majority of these problems are of mild-moderate severity. Long-term follow-up (LFTU) and screening of this population is essential.

Adolescent↗
PubMed2005

Prognostic value of MYCN and ID2 overexpression in neuroblastoma.

BACKGROUND: The molecular mechanisms driven by overexpression of the MYCN gene in neuroblastoma are not well known. Whether MYCN overexpression in the absence of genomic amplification, or ID2 overexpression has prognostic value remains controversial. PROCEDURE: Ninety-nine neuroblastic tumors from Memorial Sloan-Kettering Cancer Center and 12 neuroblastoma cell lines were analyzed by Affymetrix U95v2 Microarray System. The expression levels of the genes MYCN and ID2 were determined by RT-PCR and immunohistochemistry and the clinical value of the overexpression of both genes was determined. RESULTS: MYCN genomic amplification with overexpression was prognostic for survival (P = 0.0005). Stage 4 patients with MYCN amplification but without overexpression, had no increased likelihood of death, whereas cases with MYCN overexpression but no genomic amplification showed a low survival (P = 0.0096). ID2 did not correlate with MYCN expression (R = -0.23 for tumors and -0.27 for cell lines) or with survival (P = 0.8746). CONCLUSIONS: MYCN amplification was not related to clinical outcome in the absence of overexpression in neuroblastoma tumors. ID2 expression appears to be independent of MYCN expression and lacks prognostic value.

Biomarkers, Tumor↗
PubMed2005

Rituximab therapy of lymphoma is enhanced by orally administered (1-->3),(1-->4)-D-beta-glucan.

By activating complement, antitumor monoclonal antibodies coat tumor cells with iC3b. beta-glucans, naturally occurring glucose polymers, bind to the lectin domain of the leukocyte receptor CR3, prime it for binding to iC3b, and trigger cytotoxicity of iC3b-coated tumor cells. We studied the combination of the complement-activating antibody rituximab with barley-derived (1-->3),(1-->4)-beta-D-glucan (BG) against CD-20 positive lymphoma xenografts in SCID mice. Growth of established subcutaneous non-Hodgkin's lymphoma (NHL) (Daudi and EBV-derived B-NHL) or Hodgkin's disease (Hs445 and RPMI6666) was significantly suppressed in mice treated with a combination of intravenous rituximab and oral BG, when compared to mice treated with rituximab or BG alone. Survival of mice with disseminated lymphoma was significantly increased in the combination group as compared to other treatment groups. No clinical toxicity was observed. The therapeutic efficacy and lack of toxicity of this combination supports further investigation into its clinical utility.

Administration, Oral↗
PubMed2005

Radioimmunotargeting of human rhabdomyosarcoma using monoclonal antibody 8H9.

Although metastatic rhabdomyosarcoma (RMS) is chemotherapy and radiotherapy responsive, few patients are cured. 8H9, a murine IgG(1) monoclonal antibody, recognizes a unique cell surface tumor antigen broadly distributed on neuroectodermal, epithelial, and mesenchymal tumors, including RMS. We now report on the in vitro characterization of radiolabeled 8H9 and its in vivo immunotargeting potential in mice with subcutaneous human RMS. Saturation-binding studies carried out to determine (125)I-8H9 affinity to the RMS cell line HTB82 demonstrated that (125)I-8H9 had a K(d) of 10.3nM with an estimated 115,000 binding sites on every HTB82 cell. (125)I-8H9 was retained on the cell surface without significant internalization. Biodistribution of (125)I-8H9 was studied in athymic mice bearing HTB82 xenografts. Following intravenous injection of 4.44MBq of (125)I-8H9, selective tumor uptake was evident 4 to 172 hours after injection. Average tumor uptake was 7.0 +/- 1.8, 11.5 +/- 3.9, 15.1 +/- 3.7, and 5.4 +/- 1.2% injected dose per gram at 4, 24, 48, and 172 hours, respectively. Mean tumor: tissue ratios were maximal at 172 hours (for lung, 4, kidney, 6, liver, 7, spleen, 11, femur, 14, muscle, 18, and brain, 48). Established RMS xenografts treated with a single injection of 18.5 MBq (131)I-8H9 were significantly suppressed compared to controls. Radiolabeled 8H9 effectively targeted RMS xenografts and may have a potential clinical role in radioimmunotherapy.

Animals↗
PubMed2005

Antibody-based targeted radiation to pediatric tumors.

Radioimmunotherapy (RIT) for pediatric tumors remains in its infancy despite its potential as an attractive therapeutic modality. Most childhood tumors are radiation sensitive, but the side effects of external beam radiation are well recognized. Despite achieving complete remissions with sophisticated combination therapies, treatment failure primarily results from the inability to eradicate minimal residual disease, which is typically distant and occult. RIT can conceivably target such disease and improve cancer treatment. Because intensive chemotherapy regimens used in most childhood cancers are highly immunosuppressive, repeated administration of radiolabeled monoclonal antibodies is possible without the immediate induction of human antimouse or human antichimeric antibody responses. Despite the differences in biology between childhood and adult hematologic malignancies, they share several tumor antigens for which RIT agents are now available. However, safety and efficacy profiles in children remain to be defined. On the other hand, the antigen repertoire of pediatric solid tumors differs substantially from that in adults, partly because of differing lineages: pediatric solid tumors are typically of embryonal origin, whereas adult tumors are usually carcinomas of epithelial origin. Hence, RIT agents licensed for adult tumors are generally not applicable to pediatric solid tumors. Tumor-selective radioimmunoconjugates specific for embryonal tumors of childhood are currently being actively investigated. Without substantial policy changes in drug development for orphan indications, however, these agents are not likely to be widely available in the near future.

Adolescent↗
PubMed2004

Reduction from seven to five cycles of intensive induction chemotherapy in children with high-risk neuroblastoma.

PURPOSE: We previously reported a high response rate with a dose-intensive chemotherapy regimen in 24 children with high-risk neuroblastoma (NB). We now describe similar results with changes that reduce toxicity (fewer cycles, less vincristine, use of granulocyte colony-stimulating factor). PATIENTS AND METHODS: Eighty-seven consecutive newly diagnosed children with high-risk NB underwent induction that initially had seven cycles (57 patients) but was later limited to five (30 patients). Cycles 1, 2, 4, and 6 used cyclophosphamide (140 mg/kg)/doxorubicin (75 mg/m(2))/vincristine (0.15 mg/kg in the first 27 patients, 0.067 mg/kg subsequently). Cycles 3, 5, and 7 used cisplatin (200 mg/m(2))/etoposide (600 mg/m(2)). Tumor resection followed a minimum of three cycles. The induction was eventually modified to include anti-G(D2) immunotherapy after each of the last three cycles (38 patients). RESULTS: Bone marrow disease resolved in 70 (91%) of 77 patients and was not detected pre- and postinduction in 10 patients. After cycle 3 or 4, 86% of primary tumors were more than 50% smaller. Postinduction metaiodobenzylguanidine scans showed normal radiotracer distribution in metastatic sites in 74 (87%) of 85 patients. Overall results were: 68 (79%) complete/very good partial responses (CR/VGPR); 14 (16%) partial responses (PR); three (3%) less than PR; one (1%) death from infection; and one patient not assessable for response. Five cycles yielded a CR/VGPR rate of 83%, compared with a 77% rate from seven cycles. Side effects were myelosuppression, mucositis, and hearing deficits; neurotoxicity was insignificant with the lower vincristine dosage. Four patients (each received seven cycles) developed myelodysplasia/leukemia. CONCLUSION: Five cycles of this induction regimen, plus surgery, suffice to achieve CR/VGPR in approximately 80% of children with high-risk NB.

Antibodies↗