University of Vermont

College of Medicine

Department of Pathology and Laboratory Medicine

shukla_lab

Shukla Lab Research

Mission statement

Research: To unravel the molecular basis of asbestos-induced diseases including mesothelioma and lung cancer and develop therapeutic strategies. My work emphasizes on studying signaling pathways involved in causing these diseases.

Education: To create an excellent research environment and mentoring to all laboratory members as well as to students who want to gain research experience. Our mission is to prepare our students to achieve their goals and become successful in the field of biomedical sciences.

Overview of current areas of research and approaches

Signaling pathways in mesothelioma: The main goal of my lab is to identify signaling pathways involved in malignant mesothelioma (MM) tumorigenesis and drug resistance and then target them in combination with chemotherapeutic drugs. Recently we have shown that cyclic AMP response element binding protein (CREB) is constitutively activated in MM cells and tissues and its inhibition results in increased Doxorubicin-induced apoptosis. We have related this phenomenon to several CREB-regulated tumorigenic genes. In vivo experiments using SCID mice and genetically modified human MM cells also confirmed that CREB inhibition in combination with chemotherapeutic drug plays a significant reduction in tumor volume. Presently we are in the process of understanding these mechanisms in detail. In addition to CREB our lab has long been interested in extracellular signal regulated kinase1, 2 and 5 (ERK1/2 and ERK5) as ERK is the most prominent MAPK to be activated by asbestos in lung epithelial and mesothelial cells. Using various in vitro and in vivo approaches we have shown that ERK2 is indispensable for epitheliod MM growth whereas for fibrosarcomatoid MM both ERK1 and 2 are required. In addition inhibition of both ERK1 and ERK2 sensitizes MM cells to Doxorubicin by altering various prosurvival, drug metabolizing and transporter genes.

Inflammation and mesothelioma:  Asbestos is known to cause inflammation, however, the role of inflammation in development of MM is not well studied. We have developed a mouse model to show that inflammation precedes MM development. Presently we are involved in understanding the role(s) of inflammasomes in MM tumor development using various in vitro and in vivo approaches.

Acid Prepared Mesoporous Spheres (APMS) to target MM tumors: In a collaborative project with Prof Landry (Chemistry department, UVM), we are using decorated (antibody against mesothelin, MB) APMS-TEG particles to load with chemotherapeutic drug or small interfering RNA (siRNA) for treatment of MM.

Tools and Technologies of the laboratory: We have established in vitro and in vivo models to study MM tumorigenesis. We also employ various cell and molecular biological approaches. Our lab is enriched with several well characterized MM tumor lines obtained from patients. We also have human MM tumor tissue arrays along with normal tissues. In addition we also have few primary isolates of human mesothelial cells to validate our findings obtained from immortalized human mesothelial cells. All human cell lines (Primary or tumor) are provided by our clinician collaborator, Thoracic Surgeon in NYU. We have established two SCID mouse in vivo models, subcutaneous (SC) and intraperitoneal (IP). Both models are established using two different human MM lines (epithelioid and fibrosarcomatoid). In an ip model we have shown that inflammation precedes MM development. Furthermore, many relevant genetically modified (stably inhibited or overexpressing) human MM lines have been created and frozen for present and future use. Microarray data on these lines (14) serve as rich source of information in the lab.

We are exploring asbestos-induced signaling mechanisms in human mesothelial cells as well as in different mesothelioma cell lines to be targeted by APMS beads loaded with different anti-cancer drugs. Our focus is on CREB, ERK1/2 and ERK5 and their downstream signaling proteins, as these proteins are critical targets of asbestos induced carcinogenesis.

Manuscripts:

  1. Shukla A, MacPherson MB, Hillegass JM, Ramos-Nino ME, Alexeeva V, Vacek PM, Bond JP, Pass HI, Steele C and Mossman BT: Alterations in gene expression in human mesothelial cells correlate with mineral pathogenecity. Am J Respir Cell Mol Biol 41:114-123, 2009 PMCID: PMC2701958
  2. Buder-Hoffmann SA, Shukla A, Barrett TF, MacPherson MB, Lounsbury KM, and Mossman BT: A PKC delta-dependent PKD pathway modulates ERK1/2 and JNK1/2 phosphorylation and Bim-associated apoptosis by asbestos. Am J Pathol 174:449-459, 2009 PMCID: PMC2630554
  3. Shukla A, Bosenberg MW, MacPherson MB, Butnor KJ, Heintz NH, Pass HI, Carbone M, Testa JR and Mossman BT: Activated CREB is overexpressed in human mesotheliomas and inhibits apoptosis. Am J Pathol 175:2197-2206, 2009 PMCID: PMC2774081
  4. Hillegass JM, Shukla A, Lathrop SA, MacPherson MB, Beuschel SL, Butnor KJ, Testa JR, Pass HI, Carbone M, Steele C and Mossman BT: Inflammation precedes the development of human malignant mesotheliomas in a SCID mouse xenograft model. Ann NY Acad Sci 1203:7-14, 2010 PMCID: PMC2936775
  5. Hillegass JM, Shukla A, MacPherson MB, Lathrop SA, Alexeeva V, Perkins TN, van der Vliet A, Gunter ME, and Mossman BT: Mechanisms of oxidative stress and alterations in gene expression by Libby six-mix in human mesothelial cells. http://www.particleandfibretoxicology.com/content/7/1/26 (on-line journal) Part Fibre Toxicol 7:26, 2010 PMCID: PMC2945990

Last modified June 11 2012 12:18 PM