Teachable moment in classrooms:

  1. cellular basis of life chapter – location of transmembrane proteins
  2. cellular basis of life chapter – endocytosis moves large number of molecules into the cell
  3. urinary system chapter – structures of the male urethra
  4. male reproductive system chapter – structure and function of the prostate
  5. lymphatic and immune system chapter – anatomy of lymphatic vessels

The news item:  Recently this report appeared online:

A new approach to prostate cancer offers patients more time and energy

John Grim fought prostate cancer for six years. He did radiation. He did hormone therapy. He did chemotherapy. It felt like a losing battle. The West York man lost 50 pounds. He felt weak and exhausted. The cancer spread to his bones, causing a tumor in his spine.

The article states that a prostate cancer patient was given 6 months to live because his cancer metastasized to his bones. Pluvicto treatment extended his life expectancy, allowed him to continue to work, lowered his PSA levels to 22 from 491 and restored his body weight. The article also states that the medication is radioactive, and it seeks out and kills the prostate cancer cells.

So, Why Do I Care??  In the US alone prostate cancer develops in more than 300000 people each year, and, according to the National Cancer Institute, it causes over 35000 deaths. So, developing new approaches to kill prostate cancer cells are always welcome. This is especially the case when it comes to prostate cancer cells that spread over the body.

Plain English, Please!!!  First, let’s talk about what the prostate is. The prostate gland (or prostate) is a cherry sized gland wrapped round the male urethra. The prostate functions as a gland producing a secretion that will be incorporated into the semen. The gland itself is mostly epithelial tissue, and is a site of frequent cancer formation. Both the normal and the cancerous cells of the prostate have in their cell membranes transmembrane proteins; these proteins sticks out of the cell just like the fuzz sticks out from a tennis ball. However, the prostate cancer cells have unique transmembrane protein called the Prostate Specific Membrane Antigen, or PSMA.

Second, let’s talk about what metastasis is. Some cancer cells lose their connection to the mass of growing cancer cells, and those detached cells enter the lymphatic capillaries, and travel throughout the body. They can grow into new cancers inside lymph nodes, or enter the bloodstream to start new cancer clumps. Metastasized cancers are impossible to eradicate by surgery, and chemotherapy is poorly effective in killing them.

Third, let’s talk about how Pluvicto acts. It makes intuitive sense to take advantage of PSMA on the cancer cells to target the metastasized cells for destruction. Pluvicto is a complex molecule that is made up of several functional parts. To picture the functional parts, imagine the letter D where the vertical straight line works as a sticky area that binds to the PSMA. The round part of D is a chelator that traps metals, and that function allows the D, Pluvicto, to be filled with a radioactive metal called lutetium.  When Pluvicto is infused into the bloodstream, it sticks to the PSMA on the prostate cancer cells, even on the metastasized cells. Then the cancer cells endocytose the Pluvicto and the radioactive lutetium, and the radiation damages the DNA in the nucleus, and, eventually, kills the cells.