Rajkumar Venkatramani

NSD3-NUT Fusion Oncoprotein in NUT Midline Carcinoma: Implications for a Novel Oncogenic Mechanism

UNLABELLED NUT midline carcinoma (NMC) is an aggressive subtype of squamous cell carcinoma that typically harbors BRD4/3-NUT fusion oncoproteins that block differentiation and maintain tumor growth. In 20% of cases, NUT is fused to uncharacterized non-BRD gene(s). We established a new patient-derived NMC cell line (1221) and demonstrated that it harbors a novel NSD3-NUT fusion oncogene. We find that NSD3-NUT is both necessary and sufficient for the blockade of differentiation and maintenance of proliferation in NMC cells. NSD3-NUT binds to BRD4, and BRD bromodomain inhibitors induce differentiation and arrest proliferation of 1221 cells. We find further that NSD3 is required for the blockade of differentiation in BRD4-NUT-expressing NMCs. These findings identify NSD3 as a novel critical oncogenic component and potential therapeutic target in NMC. SIGNIFICANCE The existence of a family of fusion oncogenes in squamous cell carcinoma is unprecedented, and should lead to key insights into aberrant differentiation in NMC and possibly other squamous cell carcinomas. The involvement of the NSD3 methyltransferase as a component of the NUT fusion protein oncogenic complex identifies a new potential therapeutic target.

Gorham's disease and diffuse lymphangiomatosis in children and adolescents†

Gorhams disease is a rare disorder of unknown etiology and variable clinical presentation that is characterized by proliferation of thin‐walled vascular channels resulting in destruction and resorption of osseous matrix. The condition is frequently under recognized or misdiagnosed. There is no standard treatment defined for this disease. Here we report on eight children diagnosed with Gorhams disease at our institution over a ten‐year period. Soft tissue lymphangioma was present in seven and six children had splenic involvement. Disease stabilization and improvement was observed on treatment with interferon alpha‐2b and bisphosphonate therapy. Pediatr Blood Cancer 2011;56:667–670.

Screening for cardiac dysfunction in anthracycline-exposed childhood cancer survivors.

Purpose: To examine the utility and reliability of obtaining early echocardiographic measurements of left ventricular (LV) remodeling as well as blood biomarkers of cardiac injury in asymptomatic childhood cancer survivors at risk for LV dysfunction and congestive heart failure due to past exposure to anthracycline chemotherapy. Experimental Design: Using a cross-sectional design, anthracycline-exposed childhood cancer survivors with preserved ejection fraction (EF; ≥50%) were evaluated using early echocardiographic indices and blood biomarkers of LV dysfunction. Survivors treated with ≥300 mg/m2 anthracyclines [high risk (HR): n = 100] were compared with those treated with <300 mg/m2 anthracyclines [low risk (LR): n = 50] and matched healthy controls (HC: n = 50). All echocardiograms were interpreted by an institutional cardiologist and a study cardiologist blinded to risk status. Results: Time from diagnosis was comparable for HR (12.0 years) and LR (13.2 years, P = 0.8) survivors. Echocardiograms: HR had lower LV thickness-dimension ratio (Z-score: HR: −0.62, LR: −0.03, HC: −0.02; P < 0.001), increased LV wall stress (HR: 66.7 g/cm2, LR: 56.6 g/cm2, HC: 54.2 g/cm2; P < 0.01), and higher myocardial performance index (HR: 0.51, LR: 0.46, HC: 0.46; P < 0.01). Interobserver correlation (clinical/blinded reading) for all echocardiographic indices was excellent (range: R = 0.76–0.97, P < 0.001). Blood biomarkers: With the exception of NT-proBNP (r = 0.28, P < 0.01), there was no correlation between blood biomarkers (B-type natriuretic peptide, Troponin-T, ST-2, Galectin-3) and LV dysfunction. Conclusion: Childhood cancer survivors with preserved EF 10+ years from anthracycline exposure had dose-dependent changes in echocardiographic markers of LV dysfunction. Clin Cancer Res; 20(24); 6314–23. ©2014 AACR.

Supratentorial ependymoma in children: To observe or to treat following gross total resection?†

The standard treatment for ependymoma is surgical resection followed by postoperative irradiation to the local site. The role of radiation therapy in completely resected supratentorial ependymoma has been questioned over the past two decades.

Hepatoblastoma in children with Beckwith-Wiedemann syndrome: does it warrant different treatment?

Patients with Beckwith-Wiedemann Syndrome (BWS) are predisposed to developing hepatoblastoma. Clinical data were reviewed in all cases of hepatoblastoma in patients with BWS reported in the literature and from personal cases. Patients were identified by literature review using PubMed and by a search of the authors’ local tumor registries. Fifty-six patients were identified. The median age of presentation with hepatoblastoma was 6 months (range birth-30 mo). Thirteen of 26 patients were born prematurely. Of 31 evaluable patients, 19 exhibited hemihypertrophy. Thirty-two of 33 patients with &agr;-fetoprotein data reported had elevated levels at diagnosis. Overall survival was 75% (27 of 36 patients). Of 25 patients with data who survived, 24 were treated with chemotherapy and surgery (vs. only 2 of 8 who did not survive). All 9 patients with hepatoblastoma detected by routine screening with outcomes reported were surviving at the time of the reports. Overall survival was high in patients with BWS and hepatoblastoma, especially given lower stage at presentation and when treated with surgery and chemotherapy. Future prospective trials should evaluate if BWS is independently associated with outcome and if the outcome is improved by routine screening.

A Phase I Study of Vincristine, Irinotecan, Temozolomide and Bevacizumab (Vitb) in Pediatric Patients with Relapsed Solid Tumors

Background To determine the maximum tolerated dose (MTD) and dose limiting toxicity (DLT) of irinotecan administered in combination with vincristine, temozolomide and bevacizumab in children with refractory solid tumors. Methods The study design included two dose levels (DL) of irinotecan given intravenously once daily for 5 consecutive days (DL1: 30 mg/m2, and DL2: 50 mg/m2), combined with vincristine 1.5 mg/m2 on days 1 and 8, temozolomide 100 mg/m2 on days 1-5, and bevacizumab 15mg/kg on day 1, administered every 21 days for a maximum of 12 cycles. Results Thirteen patients were enrolled and 12 were evaluable for toxicity Dose limiting toxicity observed included grade 3 hyperbilirubinemia in 1 of 6 patients on DL1, and grade 3 colitis in 1 of 6 patients on DL2. DL 2 was the determined MTD. A total of 87 cycles were administered. Myelosuppression was mild. Grade 1-2 diarrhea occurred in the majority of cycles with grade 3 diarrhea occurring in only one cycle. Grade 2 hypertension developed in two patients. Severe hemorrhage, intestinal perforation, posterior leukoencephalopathy or growth plate abnormalities were not observed. Objective responses were noted in three Wilms tumor patients and one each of medulloblastoma and hepatocellular carcinoma. Five patients completed all 12 cycles of protocol therapy. Conclusions Irinotecan 50 mg/m2/day for 5 days was the MTD when combined with vincristine, temozolomide and bevacizumab administered on a 21 day schedule. Encouraging anti-tumor activity was noted. Trial Registration ClinicalTrials.gov; NCT00993044; http://clinicaltrials.gov/show/NCT00993044

Clinical outcomes of radiation therapy in the management of Langerhans cell histiocytosis.

Objectives:Langerhans cell histiocytosis (LCH) is a rare disease with variable clinical presentation. In the present study, we report on the effectiveness and clinical complications of radiation therapy in children with LCH. Materials and Methods:We retrospectively reviewed all patients with LCH treated with radiation therapy over a 6-decade period at a single institution. Radiotherapy data, clinical features, radiographic data, and vital status were analyzed. Results:The mean age at diagnosis for 69 patients was 5.3 years (3 mo to 37 y) and the median duration of follow-up was 6 years (7 d to 32 y). Radiation therapy was performed for 169 sites, primarily bone lesions. The median radiotherapy dose was 10 Gy (2.5 to 45 Gy). Radiographic follow-up data were available for 139 of the sites treated and clinical follow-up was available for 156 of sites treated. The radiographic local control was 91.4%, and 13% of lesions showed complete sclerosis or reconstitution of bone. A total of 90.4% of patients reported stabilization or improvement in lesion-related symptoms, most often pain. Twelve patients had diabetes insipidus at diagnosis or during follow-up. Eight of these patients received radiation treatment to the pituitary and none experienced a reduction in desmopressin dosage posttreatment. Radiation complications were few, including femoral neck fracture in 1 patient and facial asymmetry in 3 patients. No secondary malignancies were observed. Conclusions:Radiotherapy for LCH has high rates of local control and symptomatic improvement. Importantly, however, there is evidence of short-term and long-term morbidity when children are treated with low-dose irradiation.

Tumor necrosis predicts survival following neo-adjuvant chemotherapy for hepatoblastoma†‡

Tumor response to chemotherapy has been shown to predict outcome in children with acute lymphoblastic leukemia, osteosarcoma, and Ewing Sarcoma. We evaluated whether tumor necrosis following neo‐adjuvant chemotherapy is prognostic for survival in hepatoblastoma (HB).

Radiological features of Gorham’s disease

AIM To describe the key findings on plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI) of Gorhams disease. MATERIALS AND METHODS Eight children diagnosed with Gorhams disease between 1999 and 2009 were included. All imaging studies performed on each patient were reviewed with special attention to the extent of bone, soft tissue, and visceral involvement. RESULTS All patients had bone lesions at diagnosis, most commonly in the vertebrae. CT showed generalized osteopenia, multiple lytic lesions, and heterogeneous bone density. MRI demonstrated altered signal intensity in bone marrow that was hyperintense on T1 imaging. Seven patients had soft-tissue lymphangiomatous lesions adjacent to identified osseous lesions. Four patients had chylous pleural effusions: three with bilateral and one with unilateral involvement. The spleen was involved in six patients. CONCLUSION Splenic lesions and soft-tissue involvement are common in patients with Gorhams disease. The presence of extra-osseous lesions along with characteristic bone lesions on plain radiography may be pathognomonic of Gorhams disease.

Pulmonary function abnormalities in childhood cancer survivors treated with bleomycin.

Bleomycin is associated with pulmonary toxic side effects including pneumonitis and pulmonary fibrosis. We evaluated the prevalence of long‐term pulmonary function abnormalities in children receiving bleomycin therapy in the context of current chemotherapeutic regimens.