siRNA, shRNA, sgRNA, and plasmid constructs.

Lincode siRNAs targeting Lnc-BM were designed and synthesized (GE Healthcare Dharmacon) (sequences listed in Supplemental Table 3). Lincode nontargeting control siRNAs (D-001320) and ON-TARGETplus SMARTpool siRNA targeting IL6ST (L-005166) and OSMR (L-008050) (GE Healthcare Dharmacon) were used in this study. shRNAs targeting Lnc-BM were designed based on the siRNA sequence and cloned into pLKO.1-puro vector; the 2 shRNAs that produced the best knockdown efficiencies were used in the following functional studies.

CRISPR/Cas9 KO double nickase Lnc-BM plasmids were designed using 4 pairs of sgRNAs (sgRNA sequences listed in Supplemental Table 3) to generate stable knockout cell lines of 231-Br cells (Gene Editing/Cellular Model Core Facility, MD Anderson Cancer Center). Human JAK2 CRISPR/Cas9 KO plasmid (sc-400246) (detailed sgRNA sequences are listed in Supplemental Table 3), JAK2 HDR plasmid (sc-400246-HDR), and control CRISPR/Cas9 plasmid (sc-418922) were obtained from Santa Cruz Biotechnology.

The full-length pDONR223-JAK2 (Addgene 23915) was subcloned into the pBabe-SFB or Myc vector (Invitrogen). Full-length Lnc-BM and mutants were subcloned into pBabe or pCDNA3.1 backbone (Addgene). pLOC-ICAM1, pLOC-MMP9, and pLOC-RFP cDNA clones were obtained from Open Biosystems through the shRNA and ORFeome Core facility (MD Anderson Cancer Center). To generate Lnc-BM shRNA#2-resistant mammalian expression vectors, shRNA#2 targeting sequences CCAAGATTTCATAGCAATA were mutated to CCAAGACTCCGTGGCAATA. The point or domain deletion mutants were generated from the WT sequence using QuikChange Lightning Site-Directed Mutagenesis Kit (Agilent Technologies).