ABSTRACT
PURPOSE: To determine the maximum tolerated dose (MTD) of carboplatin with autologous hematopoietic stem-cell rescue, in children with poor-prognosis brain tumors. PATIENTS AND METHODS: A previously determined dose of cyclophosphamide with stem-cell rescue was used as a first course. In a second course, carboplatin was given for 3 days with stem-cell rescue to 20 children. The starting dose of carboplatin was 400 mg/m2/day with increments of 75 mg/m2/day in subsequent cohorts. Toxicity and tumor response were recorded. RESULTS: There were two grade IV toxicities at the dose level of 775 mg/m2/day. There were no toxic deaths. Thus, the MTD of carboplatin was 700 mg/m2/day for 3 days. There were six complete responses (33%, 95% confidence interval [CI], 13-59%), two partial responses (11%; 95% CI, 1-35%), four with stable diseases (22%; 95% CI, 6-48%) and six progressed (33%; 95% CI, 13-59%) out of 18 assessable. Seven of the eight responses were in primitive neuroectodermal tumors (PNETs) or Germinomas. One child with a metastatic anaplastic astrocytoma had a CR. The median duration of tumor response was 10 months (range: 1.5-87 months) with two children disease free at 66 and 87 months. Actuarial survival is 21%. Median follow-up of survivors is 35 months (range: 15-87 months). CONCLUSION: The MTD of carboplatin with stem-cell rescue is 700 mg/m2/day for 3 days. Sequential stem-cell supported cyclophosphamide and carboplatin was tolerable in children with brain tumors and produced responses in PNETs and Germinomas.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/therapy , Drug Resistance, Neoplasm , Hematopoietic Stem Cell Transplantation , Neoplasm Recurrence, Local/therapy , Salvage Therapy , Adolescent , Adult , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/therapeutic use , Antineoplastic Agents, Alkylating/administration & dosage , Antineoplastic Agents, Alkylating/therapeutic use , Carboplatin/administration & dosage , Carboplatin/therapeutic use , Child , Child, Preschool , Cyclophosphamide/administration & dosage , Cyclophosphamide/therapeutic use , Dose-Response Relationship, Drug , Female , Humans , MaleABSTRACT
Shwachman-Diamond syndrome (SDS) is a rare genetic disorder characterized by pancreatic insufficiency, short stature, skeletal abnormalities and bone marrow dysfunction. Patients with SDS have varying degrees of marrow aplasia, which can be severe or progress to leukemic transformation. While allogeneic hematopoietic stem cell transplantation (HSCT) can be curative for the hematologic disturbances of SDS, a recent review of the literature reveals few survivors. Poor outcome with HSCT is often related to excessive cardiac and other organ toxicity from transplant preparative therapy. We describe two young children with SDS who developed aplastic anemia and subsequently underwent successful allografting using a non-cardiotoxic conditioning regimen. Case 1 received marrow from an HLA-identical sibling while case 2 received partially matched umbilical cord blood from an unrelated donor. Both patients are presently alive and well with sustained donor engraftment and excellent hematopoietic function at 36 and 22 months post-HSCT.
Subject(s)
Abnormalities, Multiple/therapy , Hematopoietic Stem Cell Transplantation/methods , Bone Marrow Diseases/therapy , Child, Preschool , Exocrine Pancreatic Insufficiency/therapy , Female , Humans , Musculoskeletal Abnormalities/therapy , Syndrome , Transplantation Chimera , Transplantation Conditioning/methods , Transplantation, Homologous/methods , Treatment OutcomeABSTRACT
Previous studies have confirmed that proliferation in glioblastoma cell lines can be blocked by non-isoform specific protein kinase C (PKC) inhibitors, e.g calphostin C, staurosporine. However, the exact mechanism of PKC involvement is poorly understood. The aim of this study was to explore the role of specific PKC isoforms in the aberrant growth of glioblastoma. Identification of the isoform(s) critical for proliferation in glioblastoma would present a better target for the design of chemotherapeutic strategies. To this end, we screened expression on PKC isoforms in four human glioblastoma cell lines both when proliferating and in a quiescent state using western assays. PKC isoforms alpha, beta, betaII and zeta were found to be expressed in all cell lines. PKC epsilon was detected in three out of four cell lines and PKC eta was detected in one out of four cell lines. Quiescence of growth resulted in down-regulation of PKC epsilon. We examined the role of these isoforms by studying the effect of PKC isoform-specific inhibitors bisindolylmaleimide-I and Gö6976 on proliferation in a panel of four human glioblastoma cell lines. Inhibition of PKC alpha and epsilon had no effect on proliferation, suggesting that previous studies targeting PKC alpha may not be of therapeutic benefit. More significantly, it was shown that inhibition of PKC zeta blocked proliferation. This suggests that the inhibition of PKC zeta may be an important chemotherapeutic target for arresting growth in glioblastoma.
Subject(s)
Brain Neoplasms/metabolism , Glioblastoma/metabolism , Protein Kinase C/metabolism , Blotting, Western , Brain Neoplasms/pathology , Cell Division , Down-Regulation , Glioblastoma/pathology , Humans , Karyotyping , Phenotype , Protein Isoforms/antagonists & inhibitors , Protein Isoforms/metabolism , Protein Kinase C/antagonists & inhibitors , Tumor Cells, CulturedABSTRACT
Vasoactive intestinal peptide (VIP) is a neuromodulator and growth regulator in the developing nervous system. We analyzed 10 primitive neuroectodermal tumor (PNET) cell lines, 29 central PNET (cPNET) and 17 tumors of the Ewing's sarcoma/peripheral PNET family (ESFT) using reverse transcriptase-polymerase chain reaction (RT-PCR) and Southern hybridization. Each of the 10 cell lines and 86.2% of cPNET expressed mRNA for VIP receptor 1 (VIPR1) compared to 52.9% of ESFT. VIPR2 was expressed in 75.8% of cPNET, in 28.6% of ESFT and in all 10 cell lines. cPNET demonstrated high-affinity binding of 125I-VIP on quantitative autoradiography and in competitive binding assays. VIP inhibited tumor cell proliferation in a dose-dependent manner in 5 of 7 PNET cell lines. We conclude that VIPR1 and VIPR2 are highly expressed in cPNET and demonstrate that VIP is a growth modulator in these tumors.
Subject(s)
Gene Expression Regulation, Neoplastic/physiology , Growth Substances/genetics , Medulloblastoma/metabolism , Neuroectodermal Tumors, Primitive, Peripheral/metabolism , Receptors, Vasoactive Intestinal Peptide/genetics , Vasoactive Intestinal Peptide/genetics , Autoradiography , Blotting, Southern , Cell Division/physiology , Child , Female , Humans , Male , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, CulturedABSTRACT
We report successful use of bleomycin in a low-grade astrocytoma tumor cyst of the tectal plate. A 6-year-old male underwent subtotal resection of a low-grade astrocytoma of the tectal plate followed by chemotherapy and proton beam radiation at age 2 and a half. Despite resolution of the solid portion of the tumor, serial MRI showed enlargement of a bilobar tumor cyst 3 years after the original diagnosis. The patient developed progressive ataxia, short-term memory loss and dysconjugate gaze. Following stereotactic placement of an Ommaya reservoir into the cyst, Isovue contrast and CT scan were used to confirm the integrity of the cyst. Five consecutive daily doses of 3.0 mg of bleomycin were instilled into the cyst after removal of cyst fluid. The therapy was well tolerated in the outpatient setting, and the clinical findings resolved. Subsequent CT and MRI at 4 months and 2 years after bleomycin confirmed no recurrence of the tumor or cyst.
