Two early markers of cancer diagnosis: CD24, and APC gene polymorphism
Holy grail of cancer detection is a “yes or no” test for subclinical cancer. CD24 molecule level or certain mutations in APC gene can signal early cancer presence or increased risk for many cancers. Leading cancer expert explains:
You mentioned that you work on particular tumor markers that are available or overexpressed on the circulating normal blood cells. Dr. Anton Titov, MD You published several very interesting papers on a CD24 marker and also on the polymorphism of another gene, APC gene. Could you please describe how those markers can help detect early cancer? Polymorphism of the APC gene is very interesting. Dr. Nadir Arber, MD Although we have 3 billion bases in our genome – depends where you are coming from – changing one of them in the gene of APC in position 1307, where there is an exchange of one amino acid, isoleucine, for valine. It can tell us that these participants, these carriers are susceptible to cancer more than the general population. Especially for men, they are susceptible to more than eight cancers, different cancers. And there is an increased cancer mortality rate. Women who are less vulnerable, they are prone to three cancers: colon cancer, breast cancer, and skin cancer. But surprisingly, the overall outcome is better actually – they do better than non-carriers. This is just an example how a simple blood test – a single nuclear polymorphism in our genome – can tell us that this particular person is at a significant increased risk of having cancer. So we published it. And from the daily clinical practice, I know it is working. Because when I tell a patient to do something and to do this routine cancer checkup, I tell them, “you should do it, but it is also based on your genome” – the acceptance rate [for cancer screening] is much higher. CD24 is not a new gene, as you can see, CD24 was gene number 24 that was found. Today we have over 250 CD genes, or something like that. CD24 was one of the few earlier genes, but not many groups are working on CD24. We believe that CD24 is a very important gene. It is very important to play role upstream and it is involved in many pathways, especially in cancer pathways. CD24 is rarely expressed on normal cells. Only on B lymphocytes. CD24 has some importance in the development of the brain, kidneys and some other organs, but when you have the mouse knockout CD24 phenotype, it is normal. But we do see that CD24 is overexpressed on numerous, actually, in all cancers, which tell us that CD24 has some meaning, general importance, it’s a general phenomenon in the development of cancer. This is something that I like, because if you can use CD24 to detect cancer, or to treat cancer, we can have one test, one drug for many cancers. And indeed that we do that in the lab in mice, and now we are switching detection and treatment of cancer in human beings. So it is interesting the APC is not just the polymorphism, that one single nucleotide just could be present in a normal individual but it could indicate the increased risk for eight different cancers, not just for colorectal cancer? – Exactly, exactly! So overall, somebody who carries APC gene polymorphism, it’s between 1.5% to 2% – which is a lot of people – they have 50 to 100% more likelihood or risk to develop cancer than the general population. This is quite significant! This is what I have established, and I think you’re going to come to discuss my unique Integrative Cancer Prevention Centre, which tells these people – at least once a year you have to come to my clinic here in Tel Aviv Medical Center to do this routine screening for different cancers, because you are prone to develop it. Dr. Nadir Arber, MD I’m against ostrich strategy. [in cancer screening] We have to look with open eyes and if we are susceptible to something, to try to detect it early or even better to prevent it. Certainly! Well, that’s the only strategy to go forward, clearly! And CD24 – so normally, if a person does not have any risk of cancer, CD24 will be expressed at the low level, but if cancer risk increases, CD24 will then start to expressed at [higher level] So in other words, the strategy could be to get checked at regular intervals for the CD24 expression on all blood cells? Dr. Anton Titov, MD – Exactly! Once a year! – Once a year! This is the magic number, obviously, there is no literature, but I believe that if you do cancer screening once a year then it’s something that is doable, and it’s like testing your car. You can do it once a year.