Retina Protein Could Improve Renal Cancer Diagnosis


Kidneys perform some essential tasks for our wellbeing, filtering toxins and waste products from the blood.  They also remove acid that is produced by the cells of your body and maintain a healthy balance of water, salts, and minerals (such as sodium, calcium, phosphorus, and potassium).  Any disruption to their natural process can have negative consequences on our whole system, including nerves, muscles, and other tissues.

With kidney cancer, the initial stages generally lack specific symptoms, and the disease is often discovered in its later metastatic stages when it becomes untreatable.  The American Cancer Society estimates that patients with stage 1 renal cell carcinoma have about 81% survival rate compared to only 8% for advanced cases.


Now, researchers from Sechenov First Moscow State Medical University alongside German colleagues have proposed a quicker, far more sensitive and pain-free method for diagnosing kidney cancer.  The technique is based on measuring the immune response to arrestin-1, a retina protein that is synthesized in the cancerous cells of kidneys.

Cancer is a malignancy defined by abnormal cell division, development, or protein synthesis.  Under normal conditions, arrestin-1 is synthesized in eye retina only and its presence in another body organs may cause an intensive autoimmune response.  While arrestin-1 has already been found in other forms of cancer, like melanoma, the idea of using it as a diagnostic marker or measuring the intensity of the response to the protein have not been considered as viable screening methods.

To confirm their theory, the team dyed tissue sections, carried out blood tests, and ran DNA sequencing on samples.  Antibodies to arrestin-1 were discovered in the blood serum of 75% of patients; the protein itself was found in 90% of benign tumors and in over 50% of cancerous ones.  Increased levels of arrestin-1 were also noted in cases of metastases, especially in the brain.

The discovery of arrestin-1 synthesis in cases of kidney cancer suggests the possibility of developing anti-cancer vaccines on its basis in the near future”, explained Andrey Zamyatnin, co-author and head of the Institute of Molecular Medicine.

The diagnostic procedure would entail a simple blood test for the presence of antibodies to arrestin-1 instead of a biopsy, which is often more painful and complicated.  Because of its high sensitivity to benign growths, this approach would allow detection for the early stages when there are higher chances for recovery.