Presentation description

Metastatic breast cancer has proven to be an extremely problematic cancer diagnosis in the US. Cancer metastasis is when cancer spreads to other parts of the body. Metastatic breast cancer, which is the cause of 90% of all breast cancer related deaths, is incurable as opposed to early-stage primary breast cancer. Neutrophils, a type of immune cell, play a role in breast metastasis by aiding tumor cells through promoting the formation of new blood vessels that feed tumors with oxygen and nutrients, as well as through immunosuppression. The Welm lab studies the role of short form Ron (sfRon) tyrosine kinase receptor in breast cancer metastasis. Previous work in the Welm lab showed that mice without the sfRon gene have significantly less cancer metastasis when injected with tumor cells compared to wildtype (WT) mice. Why these sfRon knockout mice are protected from cancer metastasis is unknown. We are investigating whether sfRon knockout and WT mice have differences in neutrophils around the tumors. Previous work showed that sfRon knockout mice have fewer neutrophils in the lungs. We are testing if the neutrophils are near or in the tumors. To determine this, both types of mice were injected with breast cancer cells to allow the cancer to metastasize to the lungs. The mice were harvested 0, 7, 14, 21, and 28 days later. After harvest, the lung samples were placed on slides, and stained with hematoxylin and eosin to analyze the amount of tumor metastasis. Additionally, slides were stained for Ly6G, a marker of neutrophils, by immunohistochemistry to quantify neutrophils around those tumors. We find that there are more tumors and more neutrophils around the tumors in the WT mice. We hypothesize that sfRon kinase causes neutrophils to surround the tumors, which cause more immunosuppression and faster tumor growth.