Methods for diagnosing and treating metastatic cancer

#Generally, the present invention is directed to cancer diagnosis and treatment. More specifically, the present invention is directed to methods for diagnosing and treating metastatic cancer in a subject.

#Metastatic dissemination is the primary cause of cancer related deaths (Mehlen and Puisieux, Nat Rev Cancer 6:449-458, 2006). While surgical resection of primary tumors in concert with systemic chemotherapy has provided success in the treatment of localized cancers, metastatic disease has proven remarkably resistant to even modern targeted therapies, rendering these cancers incurable. Indeed, to mitigate the risk of future metastasis, many patients are subjected to highly morbid treatment regimens that negatively impact quality of life (Lauer et al., Expert Opin Drug Discov 10:81-90, 2015). Ostensibly, therapies that specifically target the rate limiting steps of metastatic dissemination of tumor cells could significantly improve cancer treatment by removing the threat of systemic disease and decrease our dependency on systemic therapies with their detrimental side-effects (Steeg, Nat Rev Cancer 16:201-218, 2016; Li and Kang, Pharmacol Ther 161:79-96, 2016; Zijlstra et al., Cancer Cell 13:221-234, 2008; Mehlen and Puisieux, Nat Rev Cancer 6:449-458, 2006).

#The process of metastasis is dependent on a tumour cell's ability to intravasate into the blood stream, disseminate to a distant site, evade immune detection, survive, proliferate and subsequently colonize a new microenvironment (Valastyan and Weinberg, Cell 147:275-292, 2011). Previously, it has been shown that intravasation rates are highly dependent on in vivo tumor cell motility and that when motility is inhibited using a migration-blocking antibody that targets tetraspanin CD151, both cancer cell intravasation and distant metastasis is blocked (Zijlstra et al., Cancer Cell 13:221-234, 2008; Palmer et al., Cancer Res 74:173-187, 2014). Given that the genes and signaling networks that drive in vivo motility and intravasation are different from those required for efficient primary tumor formation, identifying and interfering with these genes might prevent intravasation and metastasis. Furthermore, an improved test to detect early metastatic disease could provide a window of therapeutic opportunity prior to the full manifestation of metastasis and potentially improve overall survival for those living with advanced cancer.

#These and other features, aspects and advantages of the present invention will become better understood with regard to the following description and accompanying drawings wherein:

#FIG. 1. is a graphical representation showing that genes identified in the screen are required for productive cancer cell invasion in vivo. a) Metastatic colonies produced by HEp3 cells transduced by scramble shRNA or shRNAs targeting Kif3b, SRPK1 or Nr2f1. Insets show representative cell tracks within the metastatic colonies. b) Left panel shows invasive fronts of primary tumors produced by HEp3 cells transduced by scramble shRNA or shRNAs targeting Kif3b, SRPK1 or Nr2f1. Insets show representative cell tracks at the invasive fronts. Right panel shows invasive cells from red dashed squares in the left panel. Color-coded arrows point to cell protrusions formed by the individual, correspondingly color coded labeled cells (c1-c3). c) Individual cell tracks velocities for control and mutant cell lines from (a). d) Individual cell tracks displacement rate (productivity) for control and mutant cell lines from (a). e) Individual cell tracks velocity for control and mutant cell lines from (b). d) Individual cell track displacement rate for control and mutant cell lines from (b). g) Number of invasive cells per field that migrated out of the primary tumors for cell lines from (b). h) Number of cell protrusion per cell for control and mutant cell lines from (b).

#FIG. 2. is a graphical representation showing that targeting the screen identified genes blocks spontaneous cancer cell metastasis in vivo. a) Stereo-fluorescent images of the nude mice lungs that were subcutaneously injected with control (scramble) shRNA transduced HEp3 cells or HEp3 cells stably expressing shRNAs targeting Kif3b, SRPK1 and Nr2f1; b) Precise quantification of HEp3 cancer cells metastasized to lung as determined by human a/u q-PCR. Data is expressed as relative metastatic burden in percentage, and as total number of cancer cells detected (colored numbers) when estimated using a standard curve; c) Primary tumor weight of control and knockdown cell lines induced tumors used in the experiment.

#The following description is of one particular embodiment by way of example only and without limitation to the combination necessary for carrying the invention into effect.

#According to an embodiment, there is provided a method for preventing metastasis in a subject having cancer. The method involves modulating the gene expression of at least one of kinesin-like protein 3b (Kif3b), serine/threonine-protein kinase 1 (SRPK1), transmembrane protein 229b (TMEM229b), chromosome 14 open reading frame 142 (C14orf142), nuclear receptor subfamily 2, group F, member 1 (Nr2f1), miRNA 130b, miRNA 374b or miRNA 122 in the cancerous tumor. In some embodiments, the method involves reducing, preventing or “silencing” expression of at least one of Kif3b, ACTB, SRPK1, TMEM229b, C14orf142, KB-1460A1.5, ACTC1, Nr2f1, KIAA0922, KDELR3, APBA2, miRNA 130b, and miRNA 374b 122 in the cancerous tumor. In other embodiments, the method involves increasing expression of miRNA 122 in the cancerous tumor.

#Using the method described herein, the expression of Kif3b, ACTB, SRPK1, TMEM229b, C14orf142, KB-1460A1.5, ACTC1, Nr2f1, KIAA0922, KDELR3, APBA2, miRNA 130b, miRNA 374b, or miRNA 122 was found to be associated with cancer motility and modulating the expression of these genes prevented the cancer from spreading from a focal lesion.