B7 homologue 3 as a prognostic biomarker and potential therapeutic target in gastrointestinal tumors.

The most common digestive system (DS) cancers, including tumors of the gastrointestinal tract (GIT) such as colorectal cancer (CRC), gastric cancer (GC) and esophageal cancer (EC) as well as tumors of DS accessory organs such as pancreatic and liver cancer, are responsible for more than one-third of all cancer-related deaths worldwide, despite the progress that has been achieved in anticancer therapy. Due to these limitations in treatment strategies, oncological research has taken outstanding steps towards a better understanding of cancer cell biological complexity and heterogeneity. These studies led to new molecular target-driven therapeutic approaches. Different in vivo and in vitro studies have revealed significant expression of B7 homologue 3 (B7-H3) among the most common cancers of the GIT, including CRC, GC, and EC, whereas B7-H3 expression in normal healthy tissue of these organs was shown to be absent or minimal. This molecule is able to influence the biological behavior of GIT tumors through the various immunological and nonimmunological molecular mechanisms, and some of them are shown to be the result of B7-H3-related induction of signal transduction pathways, such as Janus kinase 2/signal transducer and activator of transcription 3, phosphatidylinositol 3-kinase/protein kinase B, extracellular signal-regulated kinase, and nuclear factor-κB. B7-H3 exerts an important role in progression, metastasis and resistance to anticancer therapy in these tumors. In addition, the results of many studies suggest that B7-H3 stimulates immune evasion in GIT tumors by suppressing antitumor immune response. Accordingly, it was observed that experimental depletion or inhibition of B7-H3 in gastrointestinal cancers improved antitumor immune response, impaired tumor progression, invasion, angiogenesis, and metastasis and decreased resistance to anticancer therapy. Finally, the high expression of B7-H3 in most common cancers of the GIT was shown to be associated with poor prognosis. In this review, we summarize the established data from different GIT cancer-related studies and suggest that the B7-H3 molecule could be a promising prognostic biomarker and therapeutic target for anticancer immunotherapy in these tumors.

Abiotrophia defectiva liver abscess in a teenage boy after a supposedly mild blunt abdominal trauma: a case report.

BACKGROUND: A pyogenic liver abscess (PLA) represents a pus-filled cavity within the liver parenchyma caused by the invasion and multiplication of bacteria. The most common offender isolated from the PLA in children is Staphylococcus aureus. Abiotrophia defectiva is a Gram-positive pleomorphic bacterium, commonly found in the oral cavity, intestinal, and genitourinary mucosa as part of the normal microbiota. It has been proven to be an etiological factor in various infections, but rarely in cases of PLA. The case presented here is, to the best of our knowledge, the first pediatric case of PLA caused by A. defectiva. CASE PRESENTATION: A 13-year-old Caucasian boy presented with a two-day history of abdominal pain, fever up to 40 °C, and polyuria. Contrast-enhanced computed tomography (CT) scan revealed a single, multiloculated liver lesion, suggestive of a liver abscess. The boy had sustained a bicycle handlebar injury to his upper abdomen 3 weeks before the symptoms appeared and had been completely asymptomatic until 2 days before admission. He was successfully treated with antibiotic therapy and open surgical drainage. A. defectiva was isolated from the abscess material. Histopathology report described the lesion as a chronic PLA. CONCLUSIONS: A. defectiva is a highly uncommon cause of liver abscess in children. In such cases, various predisposing factors should be considered, including antecedent blunt abdominal trauma.

Chronic necrotizing pulmonary aspergillosis in an immunocompetent, obese 10-year-old boy.

Chronic necrotizing pulmonary aspergillosis is a rare form of pulmonary aspergillosis. It is usually seen in middle-aged or elderly patients with underlying chronic lung disease or mild immunodeficiency, and has been only rarely encountered in children. Clinical presentation is variable and usually involves constitutional symptoms of several months' duration as well as respiratory symptoms. We present a previously well, immunocompetent, obese 10-year-old boy with cough and mild hemoptysis lasting for a couple of days and a round pulmonary infiltrate on chest radiograph. Further diagnostic investigations revealed the histopathological features of chronic necrotizing pulmonary aspergillosis in excised lung tissue, and Aspergillus fumigatus was isolated in lung tissue culture. This is one of the youngest described patients with this semi-invasive form of aspergillosis.

Cystic echinococcosis in children - the seventeen-year experience of two large medical centers in Serbia.

Cystic echinococcosis (CE) is a public health problem in countries having such endemic areas. Epidemiological studies of CE, especially pediatric, are rare. The aim of this study was to evaluate epidemiological and clinical characteristics of CE in children in Serbia. Data were obtained retrospectively from the case records of patients under the age of 18 years admitted for surgical treatment of CE at two large pediatric medical institutions in the period 1990-2006. Patients' age, number of cysts and their anatomic location were evaluated in relation to differences by patients' gender and socio-geographic status (urban or rural origin). The study included 149 children with 272 hydatid cysts. The mean age of patients was 10.1+/-3.8 years. There were no significant differences in the number of patients in relation to gender and urban:rural origin. There were no significant differences in patients' age at the time of surgery or the number of cysts per patient when patients' gender or socio-geographic status was evaluated. The anatomic location of cysts was as follows: liver (N=165; 60.7%), lungs (N=82; 30.1%), and other locations (N=25; 9.2%). Multiple cysts, and combined liver/lung involvement were identified in 34.2% (N=51), and 6.0% (N=9) of patients, respectively. Hepatic cysts were significantly more common in girls than in boys. There were no significant differences in anatomic location of cysts between socio-geographic groups. The large number of infected children during a long period of investigation indicates an active transmission of disease and a lack of program for control and prevention of CE in Serbia.