Lin-28 homolog B is a protein that in humans is encoded by the LIN28B gene. The protein encoded by this gene belongs to the lin-28 family, which is characterized by the presence of a cold-shock domain and a pair of CCHC zinc finger domains. This gene is highly expressed in testis, fetal liver, placenta, and in primary human tumors and cancer cell lines. It is negatively regulated by microRNAs that target sites in the 3' UTR, and overexpression of this gene in primary tumors is linked to the repression of let-7 family of microRNAs and derepression of let-7 targets, which facilitates cellular transformation.
Background References
1. Qi M et al. Lin28B-high breast cancer cells promote immune suppression in the lung pre-metastatic niche via exosomes and support cancer progression. Nat Commun. 2022 Feb
2. Shu Z et al. The Lin28b/Wnt5a axis drives pancreas cancer through crosstalk between cancer associated fibroblasts and tumor epithelium. Nat Commun. 2023 Oct
Western blot analysis of Lin28B on different lysates with Rabbit anti-Lin28B antibody (HA722688) at 1/1,000 dilution.
Lane 1: HepG2 cell lysate Lane 2: MCF7 cell lysate (negative) Lane 3: JAR cell lysate Lane 4: K-562 cell lysate
Lysates/proteins at 20 µg/Lane.
Predicted band size: 30 kDa Observed band size: 35 kDa
Exposure time: 10 seconds; ECL: K1801;
4-20% SDS-PAGE gel.
Proteins were transferred to a PVDF membrane and blocked with 5% NFDM/TBST for 1 hour at room temperature. The primary antibody (HA722688) at 1/1,000 dilution was used in 5% NFDM/TBST at 4℃ overnight. Goat Anti-Rabbit IgG - HRP Secondary Antibody (HA1001) at 1/50,000 dilution was used for 1 hour at room temperature.
Immunocytochemistry analysis of JAR cells labeling Lin28B with Rabbit anti-Lin28B antibody (HA722688) at 1/100 dilution.
Cells were fixed in 4% paraformaldehyde for 20 minutes at room temperature, permeabilized with 0.1% Triton X-100 in PBS for 5 minutes at room temperature, then blocked with 1% BSA in 10% negative goat serum for 1 hour at room temperature. Cells were then incubated with Rabbit anti-Lin28B antibody (HA722688) at 1/100 dilution in 1% BSA in PBST overnight at 4 ℃. Goat Anti-Rabbit IgG H&L (iFluor™ 488, HA1121) was used as the secondary antibody at 1/1,000 dilution. PBS instead of the primary antibody was used as the secondary antibody only control. Nuclear DNA was labelled in blue with DAPI.
Beta tubulin (M1305-2, red) was stained at 1/100 dilution overnight at +4℃. Goat Anti-Mouse IgG H&L (iFluor™ 594, HA1126) was used as the secondary antibody at 1/1,000 dilution.
Flow cytometric analysis of JAR cells labeling Lin28B.
Cells were fixed and permeabilized. Then stained with the primary antibody (HA722688, 1/1,000) (red) compared with Rabbit IgG Isotype Control (green). After incubation of the primary antibody at +4℃ for an hour, the cells were stained with a iFluor™ 488 conjugate-Goat anti-Rabbit IgG Secondary antibody (HA1121) at 1/1,000 dilution for 30 minutes at +4℃. Unlabelled sample was used as a control (cells without incubation with primary antibody; black).
Lin28B was immunoprecipitated from 0.2 mg JAR cell lysate with HA722688 at 2 µg/10 µl beads. Western blot was performed from the immunoprecipitate using HA722688 at 1/2,000 dilution. Anti-Rabbit IgG for IP, AlpSdAbs® VHH(HRP) (025-100-005) at 1/5,000 dilution was used for 1 hour at room temperature.
Lane 1: JAR cell lysate (input) Lane 2: HA722688 IP in JAR cell lysate Lane 3: Rabbit IgG instead of HA722688 in JAR cell lysate