Medical Information

TUMOR MARKERS
Written by Nor ‘Azlah Mohamad Azhar

In simple words, tumor markers are proteins, or glycoproteins that if detected in human body can suggest the presence of tumor. According to Professor Onn Hashim, who has been involved in conducting researches on tumor markers for almost 10 years now, tumor markers are important to detect cancer at an earlier stage. This is because most patients usually presented at the hospital at later stage of their cancer, and at that point the rate is cure is fairly low. Therefore, if we can identify the proteins that are expressed at earlier stage of the cancer, miracles can be done. This is where tumor markers come into play.

Nonetheless, Professor Onn, who is also the author of the book Metabolisme Tubuh Manusia (MTM) reckoned that there are also some limitations to the use of tumor markers. Sometimes, noncancerous conditions can also cause the levels of certain tumor markers to increase. An example is that a protein called Prostate-Specific Antigen (PSA) is elevated not only in the event of prostate cancer, but also in a benign condition known as benign prostatic hyperplasia.  Apart from that, if we compare the tumor size with body mass, where the protein concentration produced by the tumor is low and the blood circulation itself is massive, it would be hard to detect or measure the level of the protein, just like looking for a needle in a haystack.

In addition, not everyone with a particular type of cancer will have a higher level of a tumor marker associated with that cancer. Also, even if an elevated level can suggest the presence of the tumor, this alone is not enough to diagnose cancer. This is where the efficiency of tumor markers is now highly questioned.  That is why, the diagnosis must be considered by looking at the consistent pattern of altered protein expression, instead of measuring the elevated level of an individual protein.

To look at this consistent pattern, proteomics or the study of protein structure, function, and patterns of expression is conducted.  Professor Onn, being a proteomics scientist himself is currently involved in developing potential tumor markers, which can be used to identify cancer in its early stages, and to predict the suitable treatment for it. However, he reckoned that this study is still a preliminary work, and there is a long way to go to make this happen. He has high hopes that someday, something will come up from this investigation, and that it can be applied for the sake of human kind.