View of migrated cells (taken using an iphone camera through a light microscope eye-piece) x10 magnification. The dots are migrated cells









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I'm a molecular pharmacologist, but what on earth does that mean I do at 10am on a Monday?The vast majority of my PhD in Medical Sciences has been spent in a dark room, counting. Counting breast cancer cells that have moved. YES, moved.Let's start at the beginning.I work with breast cancer cells that have been taken from a donor who had breast cancer. Cancer cells can be grown in a laboratory environment if you give them the correct nutrients and keep them at the correct temperature, a cosy 37 degrees, just like in the body. The cells I use were collected back in the 1970s and have been kept growing in the lab ever since.Cancer cells can be grown on a flat surface (or in a solution), in plastic dishes, like this:The cells grow in 'media', a solution that contains all the nutrients they need to grow. The media is usually pink as it contains phenol-red, an indicator that changes colour if the pH of the media changes (pH needs to be around 7.2-7.4 for optimum growing conditions).The cells I use most of the time look like this under a microscope (the dots are individual cells):So, those are the cells.I'm looking at some potential new drugs and I am trying to work out if they might help by blocking the movement of cancer cells.Cancer grows and spreads through the body with catastrophic effects. One way the cells get around the body is by moving. The process of cell movement, and the establishment of cancer at a secondary site in the body is called metastasis.This is a single cell migrating, taken using time lapse photography (this isn't my video) -How do I quantify if these 'new drugs' might stop the movement of the cancer cells?I use something called a, boyden chamber and this is also known as a 'chemotaxis' assay. It allows me to count the number of cells that have moved (or haven't moved) towards a drug. I put the cells in the top well, media (solution that cells grow in) without cells with drug (chemoattractant) in the bottom well and these are separated by a membrane that has small pores, big enough for the cells to get through but small enough so the cells do not just fall through. Like this:The chamber I use has 96 of these individual wells (yep 96!). The picture below shows the view looking in to the top of the chamber. I use 3 wells for each drug treatment.After leaving the cells for 4 hours I take the membrane from the chamber, scrape off the cells from the top and stain the cells that have migrated through to the other side of the membrane.Then, I look at the membrane through a light microscope and count the cells that have migrated. I spend a lot of time staring at something that looks like this -Counting takes time, but eventually I get enough information to tell me which drugs cause migration, and which can prevent it.I am sure you can appreciate, this is all on cells in a dish, and may not represent what happens in the body. A drug that performs well in my experiment have other effects on other cells in the body; it might make other cells die, or not work at all.This is very, very, very early stage research!As part of my PhD, I am also trying to understand how the drugs cause the cells to move which is a whole other ball game.If you are interested in reading more about cell migration, see here -Cell Migration Gateway - http://www.cellmigration.org/science/sci_research.shtml