No abstract

Trastuzumab has been approved for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric and gastroesophageal junction cancers (GC and GJC) in combination with chemotherapy. The aim of this HER2 early/advanced gastric epidemiology (HER-EAGLE) study was to evaluate the frequency of HER2 over-expression and to evaluate agreement on HER2 status assessment in GC and GJC patients in local laboratories versus a central laboratory in China. Tumor samples from 734 GC or GJC patients who were enrolled at 11 different hospitals in China were examined. HER2 status was assessed by immunohistochemistry (IHC), and followed by dual-color silver-enhanced in Situ hybridization (DSISH) in IHC 2+ cases. Clinicopathologic characteristics were collected from all of the patients. HER2-positive tumors were identified in 12.0% (88/734) of the GC and GJC cases. There were significantly higher rates of HER2 positivity in patients with GJC (GJC: 18.1%, GC: 9.7%, P=0.002), and intestinal-type cancers using the Lauren classification (intestinal: 23.6%, diffuse/mixed: 4.3%, P<0.0001). No significant difference in HER2 positivity was identified between resection and biopsy samples, or between early and advanced disease stages. The agreement between local laboratories and the central laboratory on HER2 status scoring was good (kappa=0.86). The main reason of HER2 status discordance between local and the central laboratories was IHC result mis-interpretation in local laboratories. These results suggest that IHC followed by DSISH testing is an accurate and cost-effective procedure in China.

The variable susceptibility to the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) treatment observed in various types of leukemia cells is related to the difference in the expression levels of death receptors, DR4 and DR5, on the cell surfaces. Quantifying the DR4/DR5 expression status on leukemia cell surfaces is of vital importance to the development of diagnostic tools to guide death receptor-based leukemia treatment. Taking the full advantages of novel nanobiotechnology, we have developed a robust electrochemical cytosensing approach toward ultrasensitive detection of leukemia cells with detection limit as low as ~40 cells and quantitative evaluation of DR4/DR5 expression on leukemia cell surfaces. The optimization of electron transfer and cell capture processes at specifically tailored nanobiointerfaces and the incorporation of multiple functions into rationally designed nanoprobes provide unique opportunities of integrating high specificity and signal amplification on one electrochemical cytosensor. The high sensitivity and selectivity of this electrochemical cytosensing approach also allows us to evaluate the dynamic alteration of DR4/DR5 expression on the surfaces of living cells in response to drug treatments. Using the TRAIL-resistant HL-60 cells and TRAIL-sensitive Jurkat cells as model cells, we have further verified that the TRAIL susceptibility of various types of leukemia cells is directly correlated to the surface expression levels of DR4/DR5. This versatile electrochemical cytosensing platform is believed to be of great clinical value for the early diagnosis of human leukemia and the evaluation of therapeutic effects on leukemia patients after radiation therapy or drug treatment.

The accurately and efficiently targeted delivery of therapeutic/diagnostic agents into tumor areas in a controllable fashion remains a big challenge. Here, a novel cancer targeting magnetic microbubble is elaborately fabricated. First, the γ-Fe 2 O 3 magnetic iron oxide nanoparticles are optimized to chemically conjugate on the surface of polymer microbubbles. Then, arginineglycine-aspartic acid-l-tumor necrosis factor-related apoptosis-inducing ligand (RGD-l-TRAIL), antitumor targeting fusion protein, is precisely conjugated with magnetic nanoparticles of microbubbles to construct RGD molecularly targeted magnetic microbubble, which is defined as RGD-l-TRAIL@MMBs. Such RGD-l-TRAIL@MMBs is endowed with the multigradient cascade targeting ability following by magnetic targeting, RGD, as well as enhanced permeability and retention effect regulated targeting to result in high cancerous tissue targeting efficiency. Due to the highly specific accumulation of RGD-l-TRAIL@MMBs in the tumor, the accurate diagnostic information of tumor can be obtained by dual ultrasound and magnetic resonance imaging. After imaging, the TRAIL molecules as anticancer agent also get right into the cancer cells by nanoparticle-and RGD-mediated endocytosis to effectively induce the tumor cell apoptosis. Therefore, RGD-l-TRAIL conjugated magnetic microbubbles could be developed as a molecularly targeted multimodality imaging delivery system with the addition of chemotherapeutic cargoes to improve cancer diagnosis and therapy.