8q24.21 is a highly amplified region in cancer and associated with many epithelial cancer such as bladder, breast, colorectal and prostate cancer. The proto-oncogene c-myc is located in this region and surrounded by many lncRNAs genes such as PCAT family, CCAT family, PRNCR1. In this study, we used CRISPR-Cas9 constructs to knock out PCAT1, PRNCR1, CASC8, CASC11 and also the sequences between PCAT1-CASC11 and CASC8-CASC11in the prostate cancer cell PC3. The transfected cells with CRISPR-Cas9 targeting CASC11 gene had less proliferation ability comparing with the transfected cells with CRISPR-Cas9 targeting PCAT1, PRNCR1 or CASC8. The role of CASC11 in cancer progression and development is obscure. In our study, The CASC11 Knockout efficiency was 90% compare to the control cell. Furthermore, the study showed the importance of CASC11 in cell proliferation by significantly decreasing in the forming colonies and the growth rate comparing to the control. Also, MMP2, MMP3 and MMP9 expression levels were detected in the transfected cell by using real time PCR and the result revealed the crucial role for CASC11 in metastasis and migration. The slug and vimentin expression levels were reduced in the transfected and the double transfected clones which indicate the possible role of CASC11 in epithelial mesenchymal transition and cell motility. Taken together, our study revealed that the lncRNA CASC11 plays important roles in prostate cancer progression and metastasis by promoting the cell proliferation and migration.