Meghen B. Browning

Rapamycin enriches for CD4+ CD25+ CD27+ Foxp3+ regulatory T cells in ex vivo-expanded CD25-enriched products from healthy donors and patients with multiple sclerosis

BACKGROUND CD4(+) CD25(bright+) regulatory T cells (Treg) can be expanded to clinical doses using CD3/CD28 Ab-coated beads plus IL-2. However, this method requires high purity of the starting population to prevent overgrowth by non-regulatory T cells. Rapamycin, an agent that inhibits T-cell proliferation but selectively spares Treg, may be a means to expand Treg from less pure CD25-enriched cells. METHODS CD25-enriched cells were prepared by a single-step immunomagnetic-selection using anti-CD25 microbeads. The cells were activated with a single addition of anti-CD3/CD28 beads and expanded in ex vivo 15-5% HS and autologous CD4(+) CD25(-) feeder cells,+/-rapamycin (0.01-20 ng/mL). IL-2 was added on day 3. Cells were rested for 2 days in ex vivo 15-5% HS and tested for phenotype, intracellular Foxp3 protein and suppressor activity. RESULTS In the absence of rapamycin, CD25-enriched fractions expanded >17 000-fold by 21 days. Although suppressor activity was detected to day 14, it declined significantly by 21 days as non-regulatory cells expanded. The addition of rapamycin inhibited expansion of non-regulatory T cells at doses > or =1 ng/mL while increasing suppressor activity and the percentage of CD4(+) CD25(+) CD27(+) Foxp3(+) cells. Rapamycin did not enrich for Foxp3(+) cells in expanded cultures of CD4(+) CD25(-) cells. Treg were also readily expanded in cultures of CD25-enriched cells obtained from patients with multiple sclerosis in the presence of rapamycin. DISCUSSION The addition of 1-20 ng/mL rapamycin to CD25-enriched cultures increased the purity of cells with the phenotype and function of Treg. This approach may alleviate the need for rigorous enrichment of Treg prior to activation and expansion for potential clinical use.

Expanding the phenotype of multifocal lymphangioendotheliomatosis with thrombocytopenia

Multifocal lymphangioendotheliomatosis with thrombocytopenia is characterized by vascular skin and gastrointestinal (GI) tract lesions, thrombocytopenia, and GI bleeding. The first patient had scattered red macules and subcutaneous nodules on the skin with involvement of the lungs, liver, omentum, and right kidney. At 10 months of age he continues to have severe GI bleeding. The second patient had innumerable vascular plaques on the skin plus muscle, bone, lung, liver, and brain involvement. She died from respiratory failure at 8 months of age due to brainstem involvement. Both patients required aggressive management of GI bleeding, but had quite different skin findings and long‐term outcomes. Pediatr Blood Cancer 2009;52:531–534.

Modified Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy for Hepatoblastoma in a Small Infant: How Far Can We Push the Envelope?

: For patients with hepatoblastoma, a timely and complete resection of the tumor is critical to the patients tumor recurrence-free survival. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), a 2-stage hepatectomy procedure, has revolutionized the surgical management of large hepatic tumors with insufficient future liver remnant (FLR) at presentation. Although existing data support the utility of ALPPS in adults with primary and metastatic hepatobiliary malignancy, the literature in children is scarce. To our knowledge, this is the first report showing clinical applicability and safety of the modified ALPPS procedure in a small infant (54 days old) with hepatoblastoma who presented with insufficient FLR. Our report suggests the modified ALPPS could potentially expand the surgical treatment alternative for small infants with large hepatoblastoma.

Chemotherapy in pediatric bone and soft-tissue sarcomas

Bone and soft-tissue sarcomas account for approximately 13% of all cancers in children and adolescents. A multidisciplinary approach involving surgeons, oncologists, radiation oncologists, and pathologists has led to a significant improvement in the overall survival of these patients. Chemotherapy has played a significant role in the treatment and outcomes of these patients. In this special focus section we will discuss the most important lessons learned about the use of chemotherapy for the treatment of these tumors.

Transabdominal Intrapericardial Approach In Liver Transplantation For Unresectable Primary Hepatic Functioning Paraganglioma With Invasion Into Hepatic Veins And Suprahepatic Vena Cava: A Surgical And Anesthesia Management Challenge

Primary hepatic functional paraganglioma is a rare form of extra-adrenal catecholamine-secreting tumor. Definitive treatment of functioning paraganglioma is challenging because of the critical location of the tumor frequently in close proximity to vital structures and risk of excessive catecholamine release during operative manipulation. We report the multidisciplinary management approach for a case of unresectable primary hepatic functional paraganglioma with invasion into the hepatic veins and suprahepatic vena cava. To our knowledge, this is the first report showing that orthotopic liver transplantation is curative for patients with unresectable primary hepatic paraganglioma. For locally advanced unresectable hepatic paraganglioma that involves the intrapericardial vena cava, a meticulous pre- and intraoperative medical management and transabdominal intrapericardial vascular control of the suprahepatic vena cava during orthotopic liver transplantation allows for complete extirpation of the tumor and achieves optimal outcome.

Mosaic pathogenic HRAS variant in a patient with nevus spilus with agminated Spitz nevi and parametrial-uterine rhabdomyosarcoma

DEAR EDITOR, The role of HRAS mutations in the pathogenesis of various human cancers is well established. Recent studies indicate that cutaneous nevi can also harbour HRAS, KRAS and NRAS mutations and this group of RAS-mutation positive birthmarks has been referred to as the mosaic RASopathies. In a subset of cases, these segmental and Blaschkoid nevi may be associated with benign or malignant neoplasms of other organ systems containing the same genetic mutation. There is a growing literature reporting rhabdomyosarcoma in association with mosaic RASopathies. KRAS mutations have been reported in association with phakomatosis pigmentokeratotica and rhabdomyosarcoma in the same patient. Congenital melanocytic nevi (CMN) are known to be caused by NRAS mutations. Rhabdomyosarcoma has also been reported in at least six patients with CMN, although genetic testing of NRAS was not performed in these cases. Somatic mutations and

Patient-reported neuropathic pain in adolescent and young adult cancer patients

Neuropathic pain, a known complication of cancer and its treatments, negatively impacts quality of life. There are limited data using screening tools to aid in the diagnosis of neuropathic pain in cancer patients. Our primary objective was to determine the proportion of adolescent and young adult cancer patients reporting neuropathic pain on a patient‐completed, neuropathic pain screening tool.

En bloc resection of a C-1 lateral mass osteosarcoma: technical note

Osteosarcoma is an aggressive primary bone tumor. It is currently treated with multimodality therapy including en bloc resection, which has been demonstrated to confer a survival benefit over intralesional resection. The authors present the case of an 8-year-old girl with a C-1 lateral mass osteosarcoma, which was treated with a 4-stage en bloc resection and spinal reconstruction. While technically complex, the feasibility of en bloc resection for spinal osteosarcoma should be explored in the pediatric population.