SEMA7A as a biomarker for Diagnosis of Renal Cell Carcinoma
Renal cell carcinoma (RCC) is the most common type of kidney cancer and the deadliest of genitourinary tumours in the Western population. Renal cell cancer starts in the lining of the tubules and counts different histologic subtypes amongst which the clear cell renal carcinoma (ccRCC, most frequent type with almost 80% of cases), papillary renal cell cancer, chromophobe renal cell cancer and other less common types. Most of symptoms associated with RCC (hematuria, pain in the flank, mass in the abdomen with important weight loss and fever…) are not exclusive to RCC and do not occur until advanced stages of the disease. Indeed, RCC develops asymptomatically for a long period of time and is often diagnosed incidentally, usually at metastatic stage with poor prognosis.
Renal cell carcinoma is very resistant to conventional radiation and chemotherapy and poorly sensitive to immunotherapy. Anti-angiogenic molecules such as VEGF, protein tyrosine kinases and mTOR inhibitors have enabled great progress in terms of survival and quality of life, but they show important side effects (i.e. blood pressure and digestive toxicity). Furthermore, patients acquire resistance to these drugs. To be efficiently operable, RCC must be confined to the kidney or sparsely extended to surrounding tissues. This implies early detection of the disease. Currently, diagnosis is restricted to imaging and biopsies techniques. Indeed there is no single biomarker for RCC, especially for early stage RCC.
Thus, the present invention relates to a method for diagnosing RCC in a subject, using SEMA7A as an early biomarker for RCC. SEMA7A levels were significantly reduced in patients one month after nephrectomy, and almost inexistent in healthy donors. More importantly, SEMA7A was detected in all grades IV of RCC at similar levels, suggesting that it could be an early stage biomarker.