SURF/SURG-Department of Biological Sciences - Carnegie Mellon University

Summer Undergraduate Research Fellowship (SURF) and Small Undergraduate Research Grants (SURG)

Sponsored by the Undergraduate Research Office (URO)

2011 SURF Recipients Participating in SURP

Areej Ali

Areej Ali, Carnegie Mellon University

David Huang

David Huang, Carnegie Mellon University

Analysis of SNF5 Function in Candida albicans

Dylan Mori

Dylan Mori, Carnegie Mellon University

Kathryn Supko

Kathryn Supko, Carnegie Mellon University

Contributions of Hormonal and Epidermal Growth Factor Receptor Pathways to Lung Cancer and Melanoma

Numerous studies have linked steroid hormones to lung cancer and melanoma. Epidermal growth factor receptor (EGFR) tyrosine kinases are often overexpressed in many carcinomas. In many cancers, cross-talk occurs between hormonal signaling pathways and the EGFR pathway. We hypothesized that hormonal and EGFR pathways together contribute to lung cancer and melanoma tumorigenesis. Our aims are: 1) to determine if there is a relationship between EGFR family members and hormonal signaling pathways and 2) to identify mutations in the ERBB4 gene in a panel of lung cancer and melanoma cell lines. We evaluated the expression of members of these pathways through Western analysis. EGFR family members were expressed in all lung cancer cell lines, with the lowest expression in 91T cells. Lung cancer cell lines expressed ERβ and PR-B, but not ERα. Melanoma cell lines had no detectable ERα or PR and expressed highly variable levels of ERβ and EGFR family members. Immunohistochemistry confirmed expression results of these receptors in patient tumor samples. We next determined the level of EGFR family ligands by ELISA. We observed that amphiregulin, but not transforming growth factor alpha or heparin-binding EGF-like growth factor, levels corresponded with EGFR expression levels. The level of neuregulin-3 was consistent with the expression of HER4. Through our screening of the ERBB4 gene by PCR and sequencing, we did not identify any of the known mutations in the cell lines we examined. The long-term goal of this research is to aid in the development of new targeted treatments for these cancers. Our results suggest hormonal signaling pathways may be a novel treatment target for both lung cancer and melanoma patients, either alone or in combination with therapy targeting the EGFR pathway. This work could also aid in the identification of novel biomarkers for lung cancer and melanoma.

Nicolas Zuniga-Penaranda

Nicolas Zuniga-Penaranda, Carnegie Mellon University

Auditory-Motor Priming

Sounds help people understand their world: for example, the sounds of footsteps followed by a knock on a door can mean to us that uncle Ron walked down the hall and wants to talk. Although the sounds of actions are nothing more than complex waveforms, we somehow draw from them a wealth of information about the world and events within it. Converging evidence from neuro-imaging research indicates strong connections between sensory and motor systems. However, behavioral auditory research in the area remains comparatively limited. For example, studies have shown that viewing the video of a finger movement facilitates congruent motions, and inhibits incongruent motions in subjects. The goal of the current project is to discover whether hearing sounds of human actions can also cause this pattern of facilitation and inhibition that we call auditory-motor priming (i.e. participants responded faster than normal when the sound they hear matches the gesture they make, and vice-versa). Our specific aim was to develop an experimental methodology allowing us to study the aforementioned hypothesis. Because the method for such a study did not previously exist, the project has consisted of iteratively piloting and refining an initial paradigm, to remove all possible confounded variables. Participants used an interface consisting of a flat surface and two handles. On each trial, they were presented with a series of two stimuli: a prime (recorded tap or scrape sound) that they were told they could ignore, and the target “right” or “left”. They were instructed to respond to “left” by tapping the left handle, to “right” by scraping the right handle. Reaction times were recorded. We found that tapping sounds caused the aforementioned priming effect. However, the scrape sound did not produce this effect. Why only some sounds produce priming is perhaps a question worthy of future research.