Effective gene therapy of biliary tract cancers by a conditionally replicative adenovirus expressing uracil phosphoribosyltransferase: significance of timing of 5-fluorouracil administration

In order to enhance the efficacy of conditionally replicating adenoviruses (CRAd) in the treatment of cancers of the biliary tract, we studied the efficacy in vitro and in vivo of AxE1CAUP, a CRAd vector that carries a gene for uracil phosphoribosyltransferase (UPRT), which converts 5-fluorouracil (5-FU) directly to 5-fluorouridine monophosphate and greatly enhances the cytotoxicity of 5-FU. AxE1CAUP replicated and induced an increased UPRT expression in biliary cancer cells more efficiently than AxCAUP, a nonreplicative adenovirus carrying the UPRT gene. Whereas AxCAUP and AxE1AdB, a CRAd without the UPRT gene, modestly increased the sensitivity of BC cells to 5-FU, AxE1CAUP markedly increased the sensitivity, especially when the timing of 5-FU administration was appropriately chosen. AxE1CAUP replicated much less efficiently in normal WI-38 fibroblasts without any change in the sensitivity to 5-FU. In nude mice with s.c. biliary cancer xenografts, i.t. AxE1CAUP/5-FU therapy inhibited tumor growth significantly more strongly than AxCAUP/5-FU or AxE1AdB/5-FU therapy. Furthermore, in mice with peritoneally disseminated biliary cancer, i.p. AxE1CAUP efficiently proliferated in the tumors, decreased the tumor burden, and prolonged the survival of the mice when 5-FU was started 10 or 15 days after the vector inoculation, whereas earlier initiation of 5-FU resulted in early eradication of the vector and no survival benefit. The present study shows that the CRAd expressing UPRT was a more potent sensitizer of biliary cancer to 5-FU, than was a nonreplicative UPRT-encoding vector or a CRAd without UPRT gene, even at a lower dose of the vector, and that timing of 5-FU administration was a key factor to maximize the efficacy. This gene therapy with appropriately timed administration of 5-FU should be useful in overcoming the resistance of biliary cancers to 5-FU.     

High-level coexpression of JAG1 and NOTCH1 is observed in human breast cancer and is associated with poor overall survival

Aberrant activation of Notch receptors has been shown to cause mammary tumors in mice. We therefore used in situ hybridization to analyze expression of Notch ligands and receptors in human breast cancer. High levels of JAG1 and NOTCH1 were noted in a subset of tumors with poor prognosis pathologic features (P < 0.05). We therefore used tissue microarrays to analyze the expression of these genes in a collection of breast cancers from patients representing a wide spectrum of clinical stages, and from whom associated follow-up survival data was available (n = 184). Patients with tumors expressing high levels of JAG1 or NOTCH1 had a significantly poorer overall survival compared with patients expressing low levels of these genes [5-year survival rate of 42% versus 65% and median survival of 50 versus 83 months, respectively, for JAG1(Hi vs. Lo) (P = 0.01); 49% versus 64% and 53 versus 91 months, respectively, for NOTCH1(Hi vs. Lo) (P = 0.02)]. Moreover, a synergistic effect of high-level JAG1 and high-level NOTCH1 coexpression on overall survival was observed (5-year survival rate of 32% and median survival of 40 months; P = 0.003). These data (a) identify novel prognostic markers for breast cancer, (b) suggest a mechanism whereby Notch is activated in aggressive breast tumors, and (c) may identify a signaling pathway activated in poor prognosis breast cancer which can be therapeutically targeted.     

Predictors of locoregional recurrence in patients with locally advanced breast cancer treated with neoadjuvant chemotherapy, mastectomy, and radiotherapy

PURPOSE: To identify the clinical and pathologic factors predictive of locoregional recurrence (LRR) after neoadjuvant chemotherapy, mastectomy, and radiotherapy. METHODS AND MATERIALS: We retrospectively reviewed the hospital records of 542 patients treated on six consecutive institutional prospective trials using neoadjuvant chemotherapy and postmastectomy radiotherapy. The clinical stage (American Joint Committee on Cancer, 1988) was Stage II in 17%, Stage IIIA in 30%, Stage IIIB in 43%, and Stage IV (ipsilateral supraclavicular disease) in 10%. All LRRs were considered events, irrespective of the timing to distant metastases. RESULTS: The median follow-up was 70 months. The 5-year and 10-year actuarial LRR rate was 9% and 11%, respectively. The clinical factors associated with LRR included combined clinical stage, clinical T stage, ipsilateral supraclavicular nodal disease, chemotherapy response, physical examination size after chemotherapy, and no tamoxifen use (p < or = 0.04 for all factors). The pathologic predictors of LRR included the number of positive nodes, dissection of <10 nodes, multifocal/multicentric disease, lymphovascular space invasion, extracapsular extension, skin/nipple involvement, and estrogen receptor-negative disease (p 相似文献   

EUS-guided photodynamic therapy of the pancreas: a pilot study

BACKGROUND: Photodynamic therapy of pancreatic cancer by using percutaneously placed light catheters has been reported. The feasibility and safety of EUS-guided photodynamic therapy of the pancreas was studied in a porcine model. METHODS: After injection of porfimer sodium, a 19-gauge needle was inserted into the pancreas, the liver, the spleen, and the kidney under EUS guidance. A small diameter quartz optical fiber was passed through the EUS needle and used to illuminate the tissue with laser light. The tissue response to photodynamic therapy was examined. RESULTS: Localized tissue necrosis was achieved in all organs, without significant complication. There was no significant difference in inflammation induced by photodynamic therapy within the various organs. CONCLUSIONS: EUS-guided photodynamic therapy is a safe and simple technique that can induce small areas of focal tissue ablation within the liver, the pancreas, the kidney, and the spleen, and potentially could be used to treat a variety of benign and malignant conditions.     

The economic implications of three biochemical screening algorithms for pheochromocytoma

Pheochromocytoma is a rare, life-threatening condition. Using a modeling technique, we studied the economic implications of detection strategies for pheochromocytoma (third-party payer perspective). The diagnostic efficacy of biochemical tests was based on Mayo Clinic Rochester data. In all hypothetical algorithms, positive biochemical tests were followed by abdominal computerized tomography and, if negative, metaiodobenzylguanidine scintigraphy. In each hypothetical algorithm, imaging would be indicated after positive biochemical testing as follows: algorithm A, fractionated plasma metanephrine measurements above the laboratory reference range; or algorithm B, abnormal measurements of 24-h urinary total metanephrines or catecholamines. In algorithm C, subjects with fractions of plasma metanephrine at or above 0.5 nmol/liter or normetanephrine at or above 1.80 nmol/liter would undergo imaging, whereas those with values between the reference range and these cutoffs would undergo 24-h urinary measurements (total metanephrines and fractionated catecholamines) and be imaged if positive. We determined that, if 100,000 hypertensive patients (including 500 patients with pheochromocytoma) were tested, algorithm A (measurement of fractionated plasma metanephrines alone) would detect 489 pheochromocytoma patients at a cost of 56.6 million dollars, whereas B (24-h urinary measurements) would detect 457 pheochromocytoma patients for 39.5 million dollars, and C (combination of measurements of fractionated plasma metanephrines and urines) would detect 478 patients for 28.6 million dollars. None of the screening strategies for pheochromocytoma described are affordable if implemented on a routine basis in extremely low-risk patients. However, algorithm C may be the least costly, and at a reasonable level of sensitivity, for subjects in whom the suspicion of disease is moderate.     

Transfusion medicine problems and solutions for the pediatric hematologist/oncologist

Blood component transfusion is an integral part of the care of children with oncologic and hematologic conditions. The complexity of transfusion medicine may however lead to challenges for pediatric hematologists/oncologists. In this review, three commonly encountered areas of transfusion medicine are explored. The approach to the investigation and management of suspected platelet refractoriness is reviewed. The unique transfusion related challenges encountered by children undergoing stem cell transplantation are also discussed. Finally, issues arising out of the care of children with hemoglobinopathies are explored, with an emphasis on the incidence of allo- and autoimmunization.