Objective methods for diagnosing a predisposition to developing cancer, for example, bladder cancer, breast cancer, cholangiocellular carcinoma, CML, esophageal cancer, HCC, NSCLC, SCLC, osteosarcoma, pancreatic cancer, prostate cancer, renal cell carcinoma, soft tissue tumor and lymphoma, are described herein. In one embodiment, the diagnostic method involves determining an expression level of a WHSC1 or WHSC1L1 gene. The present invention further provides methods of screening for therapeutic agents useful in the treatment of WHSC1 or WHSC1L1 associated disease, such as a cancer, e.g., bladder cancer, breast cancer, cholangiocellular carcinoma, CML, esophageal cancer, HCC, NSCLC, SCLC, osteosarcoma, pancreatic cancer, prostate cancer, renal cell carcinoma, soft tissue tumor and lymphoma. The present invention further provides methods of inhibiting the cell growth and treating or alleviating symptoms of WHSC1 or WHSC1L1 associated diseases. The present invention also features products, including double-stranded molecules and vectors encoding thereof as well as to compositions including them. Also, disclosed are methods of identifying substances for treating or/and preventing lung cancer, using as an index their effect on expression of a WHSC1 or WHSC1L1 gene, or a biological activity of a WHSC1 or WHSC1L1 polypeptide.La présente invention concerne des méthodes objectives de diagnostic dune prédisposition à lapparition dun cancer, par exemple un cancer de la vessie, un cancer du sein, un carcinome cholangiocellulaire, une leucémie myéloïde chronique, un cancer de lœsophage, un carcinome hépatocellulaire, un cancer pulmonaire non à petites cellules, un cancer pulmonaire à petites cellules, un ostéosarcome, un cancer du pancréas, un cancer de la prostate, un carcinome à cellules rénales, une tumeur des tissus mous et un lymphome. Dans un mode de réalisation, la méthode de diagnostic implique une étape consistant à déterminer le niveau dexpression dun gène WHSC1 ou WHSC
