Focal lesions following intracerebral gene therapy for mucopolysaccharidosis IIIA.

OBJECTIVE: Mucopolysaccharidosis type IIIA (MPSIIIA) caused by recessive SGSH variants results in sulfamidase deficiency, leading to neurocognitive decline and death. No disease-modifying therapy is available. The AAVance gene therapy trial investigates AAVrh.10 overexpressing human sulfamidase (LYS-SAF302) delivered by intracerebral injection in children with MPSIIIA. Post-treatment MRI monitoring revealed lesions around injection sites. Investigations were initiated in one patient to determine the cause. METHODS: Clinical and MRI details were reviewed. Stereotactic needle biopsies of a lesion were performed; blood and CSF were sampled. All samples were used for viral studies. Immunohistochemistry, electron microscopy, and transcriptome analysis were performed on brain tissue of the patient and various controls. RESULTS: MRI revealed focal lesions around injection sites with onset from 3 months after therapy, progression until 7 months post therapy with subsequent stabilization and some regression. The patient had transient slight neurological signs and is following near-normal development. No evidence of viral or immunological/inflammatory cause was found. Immunohistochemistry showed immature oligodendrocytes and astrocytes, oligodendrocyte apoptosis, strong intracellular and extracellular sulfamidase expression and hardly detectable intracellular or extracellular heparan sulfate. No activation of the unfolded protein response was found. INTERPRETATION: Results suggest that intracerebral gene therapy with local sulfamidase overexpression leads to dysfunction of transduced cells close to injection sites, with extracellular spilling of lysosomal enzymes. This alters extracellular matrix composition, depletes heparan sulfate, impairs astrocyte and oligodendrocyte function, and causes cystic white matter degeneration at the site of highest gene expression. The AAVance trial results will reveal the potential benefit-risk ratio of this therapy.

Phase III study of doxorubicin/cyclophosphamide with concomitant versus sequential docetaxel as adjuvant treatment in patients with human epidermal growth factor receptor 2-normal, node-positive breast cancer: BCIRG-005 trial.

PURPOSE: Anthracyclines, taxanes, and alkylating agents are among the most active agents in treatment of adjuvant breast cancer (BC), but the optimal schedule for their administration is unknown. We performed an adjuvant trial to compare the sequential regimen of doxorubicin with cyclophosphamide (AC) followed by docetaxel (ie, AC>T) with the combination regimen of TAC. PATIENTS AND METHODS: Women with node-positive, human epidermal growth factor receptor 2-nonamplified, operable BC were stratified by number of axillary nodes and hormone receptor status and were randomly assigned to adjuvant chemotherapy with six cycles of TAC (75/50/500 mg/m² every 3 weeks) or four cycles of AC (60/600 mg/m² every 3 weeks) followed by four doses of docetaxel at 100 mg/m² every 3 weeks (AC>T). After completion of chemotherapy, radiation therapy was given as indicated, and patients with hormone receptor (HR) -positive disease received adjuvant hormonal therapy with tamoxifen and/or aromatase inhibitors. RESULTS: In 30 months, 3,298 patients were enrolled (n = 1,649 in each arm). The major baseline characteristics were well balanced between the groups. At a median follow-up of 65 months, estimated 5-year disease-free survival rates were 79% in both groups (log-rank P = .98; hazard ratio [HR], 1.0; 95%CI, 0.86 to 1.16), and 5-year overall survival rates for both arms were 88% and 89%, respectively (log-rank P = .37; HR, 0.91; 95% CI, 0.75 to 1.11). TAC was associated with more febrile neutropenia and thrombocytopenia, and AC>T was associated with more sensory neuropathy, nail changes, and myalgia. The incidence of neutropenic infection was similar in both groups. CONCLUSION: The sequential and combination regimens incorporating three drugs were equally effective but differed in toxicity profile.

TCR signal initiation machinery is pre-assembled and activated in a subset of membrane rafts.

Recent studies suggest that rafts are involved in numerous cell functions, including membrane traffic and signaling. Here we demonstrate, using a polyoxyethylene ether Brij 98, that detergent-insoluble microdomains possessing the expected biochemical characteristics of rafts are present in the cell membrane at 37 degrees C. After extraction, these microdomains are visualized as membrane vesicles with a mean diameter of approximately 70 nm. These findings provide further evidence for the existence of rafts under physiological conditions and are the basis of a new isolation method allowing more accurate analyses of raft structure. We found that main components of T cell receptor (TCR) signal initiation machinery, i.e. TCR-CD3 complex, Lck and ZAP-70 kinases, and CD4 co-receptor are constitutively partitioned into a subset of rafts. Functional studies in both intact cells and isolated rafts showed that upon ligation, TCR initiates the signaling in this specialized raft subset. Our data thus strongly indicate an important role of rafts in organizing TCR early signaling pathways within small membrane microdomains, both prior to and following receptor engagement, for efficient TCR signal initiation upon stimulation.