Bindra Lab Development of novel pediatric brain tumor radiosensitizers.

Pediatric brain tumors are devastating cancers and often are very aggressive, despite surgical resection, high-dose radiotherapy and chemotherapy. Shown here (photo 1) is a 12-month old female with an atypical teratoid/rhabdoid tumor (ATRT) who we treated recently at Yale, shortly before she succumbed to her disease. They often recur at the original site of disease, suggesting a need for better local control. Our laboratory is screening for novel radiosensitizers that target the INI1 mutation in ATRT cells.

example of segmentation isocyte Development of novel tools for cell-based screening. 

Cell-based screens are powerful because a “wider net” can be casted; i.e., an entire pathway can be interrogated in a single drug or siRNA screen. In addition, the identified drug hits have already passed a major hurdle which typically limits drug development: drug solubility and ability to penetrate cell membranes.  This is because these are almost always pre-requisites for appearing as a hit in a phenotype-based cellular screen, since they drugs typically are added directly to the cell culture medium.

3D foci Mechanisms of DNA damage response pathway competition. A single DSB, if left unrepaired, is lethal in cells. Thus, complex systems have evolved to rapidly detect and repair these lesions. HR and NHEJ represent the two major DSB repair pathways in mammalian cells. While homologous recombination (HR) utilizes homologous DNA sequences as a template for repair, non-homologous end joining (NHEJ) processes and re-ligates the exposed DNA termini of DSBs.
 CPT Photo 488=pRPA,555=RPA2_CPT_img2_MIP High-throughput, high-content screening for novel DNA repair inhibitors. Our laboratory recently developed high-throughput, high-content platforms to study the assembly of DNA repair proteins at IR-induced DSBs in cancer cells. We have optimized this system specifically to detect multiple key DSB repair proteins, including DNA-PK and BRCA1, which can serve as proxies for NHEJ and HR repair activity, respectively (example in Photo collection 1).
Development of targeted glioblastoma radiosensitizers. We have acquired isogenic cell lines and gene targeting tools from Horizon Discovery, Ltd, which will allow us to screen for GBM radiosensitizers which specifically target key mutations, such as IDH1 and PTEN. This project will begin in the summer of 2014.
Affymetix HTA microarray of RNA samples extracted from paraffin-embedded tissue Gene expression profiling as a means to assess radiation response patterns. We are attempting to determine whether there specific gene expression patterns that predict the response to radiation therapy, for diseases where local control issues persist. We have developed in-house protocols to perform microarray studies on RNA extracted from small amounts of formalin-fixed, paraffin-embedded (FFPE) tissues.
Novel methods to radiosensitize K-ras mutant lung cancer cells. Many patients with non-small cell lung cancer (NSCLC) present with locally advanced disease, which often is treated with radiotherapy plus radiosensitizing chemotherapy. Despite aggressive treatment, rates of local failure are high and overall survival rates are low. The successful use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) for tumors with activating mutations in this gene have heralded a new era of targeted NSCLC therapies.
3-color-labeling Synthetic lethal screening for novel inhibitors of pediatric rhabdomyosarcoma. Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue cancer, affecting children of all ages. Each year, approximately 300 new cases of pediatric RMS are reported in the United States (U.S.). In these children, tumors often grow and spread quickly, necessitating intensive therapy. One sub-type of RMS, known as alveolar RMS (ARMS), is particularly aggressive and difficult to treat. Children with ARMS tumors often have metastatic disease at diagnosis (Photo 1) and even after rigorous therapeutic regimens, approximately 50% of ARMS patients will suffer from recurrent disease.