Laura Roveda

Clinical lessons from the first applications of BNCT on unresectable liver metastases.

After a long series of studies on the effects of neutron irradiation of 10 B loaded neoplastic cells both in culture and in animal experiments, we started the clinical application of BNCT on humans affected by liver metastases of a radically resected colon adenocarcinoma. The procedure we adopted includes a first surgical phase, with hepatectomy; a radiotherapeutic phase, in which the isolated liver, washed and chilled, is extracorporeally irradiated with thermal neutrons; and then a second surgical phase for the reconnection of the liver to the patient. Until now two patients have been subjected to the BNCT treatment. The first one survived 44 months with a good quality of life, and died because of diffuse recurrences of his intestinal tumour. The second patient had the same early perioperative course, but after 33 days a worsening of a dilatative cardiomyopaty, from which he was suffering, determined a cardiac failure and eventually death. This clinical experience, although limited, has shown that extracorporeal neutron irradiation of the liver is a feasible procedure, able to ensure the complete destruction of liver metastases and a possible long lasting survival. In our patients neutron irradiation caused massive cellular necrosis highly specific to tumour cells, whereas normal cells were mostly spared. Nevertheless, the impact of such a traumatic operation on the patients organism must be taken into account. Finally, we have to be aware that the fight against tumour rarely leads to a complete victory. We now have an innovative weapon which is both powerful and partly unsettled: it must be refined and above all used.

Neutron autoradiography imaging of selective boron uptake in human metastatic tumours

The ability to selectively hit the tumour cells is an essential characteristic of an anti-tumour therapy. In boron neutron capture therapy (BNCT) this characteristic is based on the selective uptake of (10)B in the tumour cells with respect to normal tissues. An important step in the BNCT planning is the measurement of the boron concentration in the tissue samples, both tumour and healthy. When the tumour is spread through the healthy tissue, as in the case of metastases, the knowledge of the different kinds of tissues in the sample being analysed is crucial. If the percentage of tumour and normal tissues cannot be evaluated, the obtained concentration is a mean value depending on the composition of the different samples being measured. In this case an imaging method that could give information both on the morphology and on the spatial distribution of boron concentration in the sample would be a fundamental support. In this paper, the results of the boron uptake analysis in the tumour and in the healthy samples taken from human livers after boron phenylalanine (BPA) infusion are shown; boron imaging was performed using neutron autoradiography.

Protein–Carbohydrate Complex Reveals Circulating Metastatic Cells in a Microfluidic Assay

Advances in carbohydrate sequencing technologies reveal the tremendous complexity of the glycome and the role that glycomics might have to bring insight into the biological functions. Carbohydrate-protein interactions, in particular, are known to be crucial to most mammalian physiological processes as mediators of cell adhesion and metastasis, signal transducers, and organizers of protein interactions. An assay is developed here to mimic the multivalency of biological complexes that selectively and sensitively detect carbohydrate-protein interactions. The binding of β-galactosides and galectin-3--a protein that is correlated to the progress of tumor and metastasis--is examined. The efficiency of the assay is related to the expression of the receptor while anchoring to the interactions strength. Comparative binding experiments reveal molecular binding preferences. This study establishes that the assay is robust to isolate metastatic cells from colon affected patients and paves the way to personalized medicine.

Mass spectrometry-based identification of the tumor antigen UN1 as the transmembrane CD43 sialoglycoprotein

The UN1 monoclonal antibody recognized the UN1 antigen as a heavily sialylated and O-glycosylated protein with the apparent molecular weight of 100–120 kDa; this antigen was peculiarly expressed in fetal tissues and several cancer tissues, including leukemic T cells, breast, and colon carcinomas. However, the lack of primary structure information has limited further investigation on the role of the UN1 antigen in neoplastic transformation. In this study, we have identified the UN1 antigen as CD43, a transmembrane sialoglycoprotein involved in cell adhesion, differentiation, and apoptosis. Indeed, mass spectrometry detected two tryptic peptides of the membrane-purified UN1 antigen that matched the amino acidic sequence of the CD43 intracellular domain. Immunological cross-reactivity, migration pattern in mono- and bi-dimensional electrophoresis, and CD43 gene-dependent expression proved the CD43 identity of the UN1 antigen. Moreover, the monosaccharide GalNAc-O-linked to the CD43 peptide core was identified as an essential component of the UN1 epitope by glycosidase digestion of specific glycan branches. UN1-type CD43 glycoforms were detected in colon, sigmoid colon, and breast carcinomas, whereas undetected in normal tissues from the same patients, confirming the cancer-association of the UN1 epitope. Our results highlight UN1 monoclonal antibody as a suitable tool for cancer immunophenotyping and analysis of CD43 glycosylation in tumorigenesis.

Thirteenth International Congress on Neutron Capture Therapy.

The Thirteenth International Congress on Neutron Capture Therapy (ICNCT) was held in Florence, Italy from November 2–8, 2008. A selection of 98 out of the total of 222 papers, which were presented at this meeting, is reported in this special issue of Applied Radiation and Isotopes. Boron neutron capture therapy (BNCT) is a novel radiotherapeutic modality that based on the nuclear capture reaction that occurs when non-radioactive boron10 is irradiated with neutrons of the appropriate energy to yield high energy alpha particles and recoiling lithium-7 nuclei. Since these particles have pathlengths of approximately one cell diameter, their lethality primarily is limited to boron containing cells. BNCT, therefore, can be regarded as both a biologically and a physically targeted type of radiation therapy. Its success is dependent upon the selective delivery of sufficient amounts of B to cancer cells with only small amounts localized in the surrounding normal tissues. A wide variety of boron delivery agents have been synthesized, but only two of these currently are being used clinically. The first, which has been used in Japan and Europe to treat patients with brain tumors, is sodium borocaptate or BSH, and the second is a dihydroxyboryl derivative of phenylalanine, referred to as boronophenylalanine or BPA. This has been used clinically in Japan, Europe, Argentina and the United States to treat patients with a variety of tumors including gliomas, melanomas and head and neck cancers. Following intravenous administration of either BPA or BSH, the tumor site is irradiated with neutrons, the source of which is a specially adapted nuclear reactor. Up until recently, low-energy thermal neutron beams have been used primarily in Japan. However, they have a limited depth of penetration in tissues, and therefore higher energy, epithermal neutron beams, which have a greater depth of penetration, are now being used in clinical trials. In theory, BNCT is a highly selective type of radiation therapy that can target the tumor without causing excessive radiation damage to normal tissues. However, its effectiveness is dependent upon the selective uptake and relatively homogenous distribution of B within the tumor, and this is still one of the key stumbling blocks that has limited its success. The 13th ICNCT has brought together approximately 280 researchers and clinicians from 24 countries to discuss their latest findings in the diverse scientific fields related to BNCT. The major topics, which were discussed at this meeting included the chemistry and pharmacology of boron delivery agents, medical physics and treatment planning, nuclear reactor and accelerator neutron sources and neutron beam dosimetry, biological and radiobiological studies in cell culture and in animals, boron imaging and quantitation, and most importantly, the progress that

Boron-Loaded Liposomes in the Treatment of Hepatic Metastases: Preliminary Investigation by Autoradiography Analysis

Boronophenylalanine (BPA)-loaded conventional and stabilized liposomes were prepared by the reversed phase evaporation method to treat liver metastases by boron neutron capture therapy. Conventional vesicles were composed of phosphatidylcholine and cholesterol, molar ratio 1:1. To obtain stealth liposomes, GM1 or PEG were included in the lipidic bilayer at a concentration of 6.67 or 5 mol%, respectively. Large unilamellar vesicles were formulated encapsulating BPA in the liposome aqueous compartment as a complex with fructose; BPA free base also was embedded into the lipidic bilayer. In vivo experiments were carried out after intravenous injection of liposome suspensions in BD-IX strain rats in which liver metastases had been induced. Alpha particle spectroscopy associated with histological analysis was performed to visualize boron spatial distribution in liver. Simultaneously, tissue boron concentrations were determined using inductively coupled plasma-mass spectroscopy. Results showed that PEG-modified liposomes accumulated boron in therapeutic concentrations (> 30 micrograms boron/g tissue) in metastatic tissue. The PEG-liposomes could be further explored in enhancing boron delivery to tumor cells.

Development of a Method to Use Boron Neutron Capture Therapy for Diffused Tumours of Liver (Taormina Project)

The research informing this paper is based on the idea to treat, by BNCT, the human liver metastases by neutron irradiation of the organ outside the patient. The program, originally proposed by groups of surgeons and physicists, is supported by I.N.F.N. since 1988*.

Folic Acid Functionalized Surface Highlights 5‐Methylcytosine‐Genomic Content within Circulating Tumor Cells

Although the detection of methylated cell free DNA represents one of the most promising approaches for relapse risk assessment in cancer patients, the low concentration of cell-free circulating DNA constitutes the biggest obstacle in the development of DNA methylation-based biomarkers from blood. This paper describes a method for the measurement of genomic methylation content directly on circulating tumor cells (CTC), which could be used to deceive the aforementioned problem. Since CTC are disease related blood-based biomarkers, they result essential to monitor tumors stadiation, therapy, and early relapsing lesions. Within surfaces bio-functionalization and cells isolation procedure standardization, the presented approach reveals a singular ability to detect high 5-methylcytosine CTC-subset content in the whole CTC compound, by choosing folic acid (FA) as transducer molecule. Sensitivity and specificity, calculated for FA functionalized surface (FA-surface), result respectively on about 83% and 60%. FA-surface, allowing the detection and characterization of early metastatic dissemination, provides a unique advance in the comprehension of tumors progression and dissemination confirming the presence of CTC and its association with high risk of relapse. This functionalized surface identifying and quantifying high 5-methylcytosine CTC-subset content into the patients blood lead significant progress in cancer risk assessment, also providing a novel therapeutic strategy.

Intra-operative PAIR of hepatic echinococcal cyst after cholecystectomy with laparoscopic approach

To the editor: Open surgery has been the only therapeutic option for hepatic echinococcal cyst until medical treatment, imaging-guided percutaneous procedures [such as puncture, aspiration, injection and reaspiration (PAIR)] and laparoscopic surgery became available (1, 2). We describe what, to the best of our knowledge, is the first case of PAIR performed with a laparoscopic approach. A 51-year-old Caucasian male, who had successfully undergone PAIR for an active echinococcal cyst in the VII liver segment in 1987, presented with pain in the upper abdomen. A yearly ultrasonography (US) and serological follow-up until 1998 had showed no sign of reactivation of the cyst, but the patient interrupted follow-up until the present episode in 2002. Leucocytosis with eosinophilia, elevation of transaminases, g-glutamil transferase and alkaline phosphatase were present; serology for Echinococcus granulosus was positive. Abdominal US and computed tomography showed hepatosteatosis, cholelithiasis and an echinococcal cyst (70 50 mm) with some round daughter cysts (20 mm) in the VII–VIII segments close to the right hepatic vein and the inferior vena cava (Fig. 1); intraand extrahepatic biliary system were not dilated. A laparoscopic approach was planned to perform cholecystectomy and simultaneously treat the parasitic cyst with a fine needle aspiration and alcohol injection. After cholecystectomy, the cyst was evaluated with an intra-operative surgical probe (Fig. 2). A 20-gauge needle was inserted in the abdomen through the right IX intercostal space on the anterior axillary line. The needle was directed toward the liver surface and into the cyst under combined laparoscopic–ultrasonographic guidance (Figs 3 and 4). All the daughter cysts were aspirated (with a total amount about 25 ml of clear fluid aspirated, no bilirubin detected) and ethanol was injected (in a measure of one-third of aspirated amount), and then reaspirated after 10 min according to our standard protocol for percutaneous PAIR, with the needle being held in place for the entire

Radioimmunoassisted surgery for lung metastases from colorectal cancer: Results and perspectives

The high incidence of resectable lung metastases from colorectal cancer and the very poor prognosis of untreated patients (less than 24-month survival) has promoted the surgical approach to treatment. Since the main aims of this kind of surgery are the complete resection of the tumor, the preservation of tumor-free parenchyma, and a minimal surgical trauma, innovative surgical techniques have been developed. We report on our experience in the radioimmunoassisted pulmonary metastasectomy by the use of a hand-held gamma-detecting probe (GDP) and describe the application of the intraoperative radioimmunolocalization of tumor to video-assisted minimally invasive surgery.