Deadly KISS: Kisspeptin 10 Interaction with Osteoblasts and Breast Cancer Metastatic Cells

Open Access
Author:
Leahey, Kaitlyn Elizabeth
Area of Honors:
Biochemistry and Molecular Biology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Andrea Marie Mastro, Thesis Supervisor
  • Joseph C. Reese, Honors Advisor
  • Stephen Wade Schaeffer, Honors Advisor
  • Scott Brian Selleck, Faculty Reader
Keywords:
  • breast cancer
  • metastasis
  • osteoblasts
  • KISS1
  • Kisspeptin 10
  • cytokines
Abstract:
Metastasis is a multistep process with significant impact on survival. Current cancer research focuses on blockading metastases with the hope of increasing patient survival and prognosis. This research has spurred an interest in metastasis suppressor genes, such as Kisspeptin (KISS-1). KISS-1 is important in the reproductive axis and many cancer types, but its role in breast cancer is controversial. Because breast cancer frequently metastasizes to the skeleton, it is important to understand the interaction of bone with cancer metastases. This study focuses on the interactions among one of the proteolytic products of the Kiss-1 protein (kisspeptin-10, KP10), its receptor KISS1R (GPR54, AXOR12), murine MC3T3-E1 osteoblasts (bone forming cells), and bone-metastatic breast cancer cells, MDA-MB-231. The aim of this study was to determine if KP10 affected the interaction of osteoblasts and bone-metastatic breast cancer cells. The Mastro laboratory had previously determined that osteoblasts exhibit an inflammatory response when treated with conditioned medium from breast cancer cells. This inflammatory response may contribute to cancer cell proliferation in the bone. This response has not yet been characterized in the presence of KP10. However, previous research suggests that treatment with KP10 reduces the ability of the cancer cells to invade a reconstituted basement membrane (Matrigel) and to migrate in response to osteosarcoma cells. I hypothesized that KP10 would down regulate the inflammatory response of osteoblasts to breast cancer cells. MDA-MB-231 breast cancer cells express KISS1R; therefore, these cells were treated with KP10 (1-500 nM, 4hr), the medium was collected, and the osteoblasts were treated with it. KP10 significantly decreased the inflammatory response of osteoblasts to breast cancer conditioned media indicated by decreased levels of IL-6 as determined by ELISA. In addition, KP10 did not affect the differentiation of osteoblasts over a variety of doses or in presence of breast cancer conditioned media. This research has important implications because it provides insight into how KP10 may be acting on either the breast cancer cells or the bone cells. This project is important because it is focused on a controversial pathway that holds promise for metastatic breast cancer research and ultimately treatment.