Preliminary Study on ß3-Adrenoreceptor as Predictor Marker of Relapse in Ewing Sarcoma Patients.

Ewing sarcoma (EWS) is a paediatric aggressive malignant tumour of bones and soft tissues. Multidisciplinary chemotherapies, surgical resection, and radiation represent the only strategies counteracting the disease, however spreading and relapse of disease still remain a clinical issue. Circulating tumour cells (CTCs) are an important feature of EWS but the prognostic significance has not been, yet, clarified. CTCs have been found both in patients with localized disease and in those who recur or metastasize. The identification of markers that can detect recurrences and metastasis remains an important challenge for research. Unfortunately, even most of patients with localized cancer relapsed and the reason has not yet been fully understood. In this clinical study on EWS patients, we evaluated the expression of CD99 antigen and beta-3 adrenergic receptor (ß3-AR) on CTCs and bioptic derived cells by flow cytometry. The preliminary data revealed a higher ß3-AR expression on cells derived from metastatic or relapsed patients, suggesting a role for the ß3-AR as a possible predictive maker of disease recurrence in both patients with metastatic and localized disease.

Anti-miR21 oligonucleotide enhances chemosensitivity of T98G cell line to doxorubicin by inducing apoptosis.

Various signal transduction pathways seem to be involved in chemoresistance mechanism of glioblastomas (GBMs). miR-21 is an important oncogenic miRNA which modulates drug resistance of tumor cells. We analyzed the expression of 5 miRNAs, previously found to be dysregulated in high grade gliomas, in 9 pediatric (pGBM) and in 5 adult (aGBM) GBMs. miR-21 was over-expressed, with a significant difference between pGBMs and aGBMs represented by a 4 times lower degree of expression in the pediatric compared to the adult series (p = 0.001). Doxorubicin (Dox) seems to be an effective anti-glioma agent with high antitumor activity also against glioblastoma stem cells. We therefore evaluated the chemosensitivity to Dox in 3 GBM cell lines (A172, U87MG and T98G). Dox had a cytotoxic effect after 48 h of treatment in A172 and U87MG, while T98G cells were resistant. TUNEL assay verified that Dox induced apoptosis in A172 and U87MG but not in T98G. miR-21 showed a low basal expression in treated cells and was over-expressed in untreated cells. To validate the possible association of miR-21 with drug resistance of T98G cells, we transfected anti-miR-21 inhibitor into the cells. The expression level of miR-21 was significantly lower in T98G transfected cells (than in the parental control cells). Transfected cells showed a high apoptotic rate compared to control after Dox treatment by TUNEL assay, suggesting that combined Dox and miR-21 inhibitor therapy can sensitize GBM resistant cells to anthracyclines by enhancing apoptosis.

Delivery of doxorubicin across the blood-brain barrier by ondansetron pretreatment: a study in vitro and in vivo.

Doxorubicin (Dox) has got a limited efficacy in the treatment of central nervous system tumors because of its poor penetration through blood-brain barrier mediated by MDR efflux transporters. We investigated the possibility that ondansetron (Ond) enhances Dox cytotoxicity in cell lines interfering with P-glycoprotein and increases Dox concentration in rat brain tissues. The MDR phenotype was studied using human hepatocellular carcinoma cell line PLC/PRF/5 (P5 and P1(0.5) clones), two subclones of NIH 3T3 cells (PSI-2 and PN1A) and two glioblastoma cell lines (A172, U87MG). Rats were pretreated with Ond before injection of Dox. Quantitative analysis of Dox was performed by mass spectrometry. Our in vitro experiments demonstrated that Ond at 10 µg/ml is not toxic to all cell lines. However, Ond reverses the MDR phenotype in P1(0.5) and PN1A cell lines. In addition, we showed that pretreatment with Ond increases Dox concentration in rat brain tissues, without increasing acute heart and renal toxicity.

Genome-wide copy number analysis in pediatric glioblastoma multiforme.

Glioblastoma (GBM) is a very aggressive and lethal brain tumor with poor prognosis. Despite new treatment strategies, patients' median survival is still less than 1 year in most cases. Few studies have focused exclusively on this disease in children and most of our understanding of the disease process and its clinical outcome has come from studies on malignant gliomas in childhood, combining children with the diagnosis of GBM with other pediatric patients harboring high grade malignant tumors other than GBM. In this study we investigated, using array-CGH platforms, children (median age of 9 years) affected by GBM (WHO-grade IV). We identified recurrent Copy Number Alterations demonstrating that different chromosome regions are involved, in various combinations. These observations suggest a condition of strong genomic instability. Since cancer is an acquired disease and inherited factors play a significant role, we compared for the first time the constitutional Copy Number Variations with the Copy Number Alterations found in tumor biopsy. We speculate that genes included in the recurrent 9p21.3 and 16p13.3 deletions and 1q32.1-q44 duplication play a crucial role for tumorigenesis and/or progression. In particular we suggest that the A2BP1 gene (16p13.3) is one possible culprit of the disease. Given the rarity of the disease, the poor quality and quantity of bioptic material and the scarcity of data in the literature, our findings may better elucidate the genomic background of these tumors. The recognition of candidate genes underlying this disease could then improve treatment strategies for this devastating tumor.

Successful treatment of metastatic ßHCG-secreting germ cell tumor occurring 3 years after total resection of a pineal mature teratoma.

UNLABELLED: Patients diagnosed with intracranial teratoma are at risk for developing a recurrent malignant germ cell tumor. We describe a 14-year-old boy initially diagnosed with a mature teratoma in the pineal region that recurred as a metastatic beta-human chorionic gonadotropin (ßHCG)-secreting germ cell tumor 3 years after gross total resection. A surveillance brain MRI scan during follow-up demonstrated multiple lesions within the ventricular and subependymal area infiltrating the brain parenchyma along with concomitant elevated levels of ßHCG in both the serum and cerebrospinal fluid. The patient underwent chemotherapy with PEI (cis-platinum, etoposide, ifosfamide) followed by radiation therapy according to the SIOP CNS GCT protocol. The patient is currently alive without evidence of disease 35 months after starting therapy. CONCLUSIONS: A careful and long-term follow-up including scheduled tumor markers as well as surveillance MRI scans is required for patients with intracranial teratoma in an effort to detect and diagnose recurrent malignant disease, especially since multimodal therapy provides the potential for long-term cure.

Low-dose cisplatin-etoposide regimen for patients with optic pathway glioma: a report of four cases and literature review.

Optic pathway gliomas (OPGs) account for 5% of all childhood brain tumors. For years it has been discussed which was the best method of examining tumor progression when the magnetic resonance imaging (MRI) scan does not change. The role of chemotherapy in their treatment still remains controversial. We treated four consecutive patients affected by progressive OPG with lower cumulative doses of cisplatin/etoposide. The extension of disease was assessed by brain MRI scan. A complete ophthalmologic examination was performed. Ototoxicity was monitored. Our OPG patients had reduced visual acuity (VA) and/or visual field (VF) regardless of the MRI evaluation. All patients showed rapid visual recovery with improvement both in VA and in VF. At the time of writing, after a median follow-up of 34 months, all patients were alive and free from disease progression. Our results confirm the effectiveness and the low-toxicity profile of the cisplatin/etoposide regimen for treatment of children affected by OPG. We suggest that VA and VF can be considered as the most accurate parameters for defining the start of chemotherapy and tumor response.

Pharmacological modulation of blood-brain barrier increases permeability of doxorubicin into the rat brain.

Our group recently demonstrated in a rat model that pretreatment with morphine facilitates doxorubicin delivery to the brain in the absence of signs of increased acute systemic toxicity. Morphine and other drugs such as dexamethasone or ondansetron seem to inhibit MDR proteins localized on blood-brain barrier, neurons and glial cells increasing the access of doxorubicin to the brain by efflux transporters competition. We explored the feasibility of active modification of the blood-brain barrier protection, by using morphine dexamethasone or ondansetron pretreatment, to allow doxorubicin accumulation into the brain in a rodent model. Rats were pretreated with morphine (10 mg/kg, i.p.), dexamethasone (2 mg/kg, i.p.) or ondansetron (2 mg/kg, i.p.) before injection of doxorubicin (12 mg/kg, i.p.). Quantitative analysis of doxorubicin was performed by mass spectrometry. Acute hearth and kidney damage was analyzed by measuring doxorubicin accumulation, LDH activity and malondialdehyde plasma levels. The concentration of doxorubicin was significantly higher in all brain areas of rats pretreated with morphine (P < 0.001) or ondansetron (P < 0.05) than in control tissues. The concentration of doxorubicin was significantly higher in cerebral hemispheres and brainstem (P < 0.05) but not in cerebellum of rats pretreated with dexamethasone than in control tissues. Pretreatment with any of these drugs did not increase LDH activity or lipid peroxidation compared to controls. Our data suggest that morphine, dexamethasone or ondansetron pretreatment is able to allow doxorubicin penetration inside the brain by modulating the BBB. This effect is not associated with acute cardiac or renal toxicity. This finding might provide the rationale for clinical applications in the treatment of refractory brain tumors and pave the way to novel applications of active but currently inapplicable chemotherapeutic drugs.

Expression of ß-adrenergic receptors in pediatric malignant brain tumors.

ß-adrenergic receptors (ß-ARs) are G protein-coupled receptors that activate signal transduction pathways involved in angiogenesis, resulting in enhanced tumor vascularization and more aggressive growth. In this study, we evaluated the expression of ß-ARs in a population of 12 children affected by malignant primary brain tumors. We found a significant expression of ß1- and ß2-ARs in all 12 samples as well as the 3 cell lines tested (U87MG, T98G and DAOY). The mean absolute ß1-AR mRNA level standardized to GAPDH was 5.81 (range, -7.91 to 11.29) for brain tumors and 8.59 (range, 6.046 to 12.59) for cell lines (U87MG, DAOY and T98G), respectively. The mean absolute ß2-AR mRNA level was 4.74 (range, -9.30 to 8.45) for tumor specimens and 7.64 (range, 5.85 to 8.88) for cell lines. These real-time quantitative (qRT)-PCR expression data were confirmed by immunohistochemical analysis. Our study evaluated the presence of ß1- and ß2-ARs in malignant pediatric brain tumors and brain tumor cell lines.

Successful treatment with a low-dose cisplatin--etoposide regimen for patients with diencephalic syndrome.

Diencephalic syndrome (DS) is a rare but rapidly fatal condition, usually occurring during the first year of life, as a result of a hypothalamic/chiasmatic tumor. The purpose of this study was to induce an objective tumor response and to achieve rapid weight recovery by using ten three-day courses of reduced-dose cisplatin-etoposide. Between 2004 and 2009, eight pediatric patients with DS as a result of an hypothalamic tumor and with a median age at diagnosis of 6.5 months (range 4-60 months) received 10 monthly courses of cisplatin (25 mg/m(2)/day on days 1-3) and etoposide (100 mg/m(2)/day on days 1-3). Under chemotherapy, rapid weight recovery was observed for all patients; tumor response was observed for six (75 %; partial response in four and minimum response in two). The other two had stable disease at completion of treatment. Mean time to weight recovery was 6 months (range 5-7 months) for pilomyxoid astrocytoma patients, and 3.3 months (range 3-4 months) for those with pilocytic astrocytoma. For DS patients who received nutritional support (enteral or parenteral nutrition) the mean time for weight recovery was 5 months (range 3-7 months) whereas children who were able to orally ingest a high-energy diet had a mean time for weight recovery of 8.66 months (range 3-19 months). After follow-up ranging from 22 to 89 months (median 38 months) all patients are alive. A low-dose cisplatin-etoposide regimen is highly effective regarding tumor response and treatment of DS symptoms/cachexia without causing significant side-effects.