Fig 2: TAGLN2 expression levels are upregulated in CRC cell lines, but TAGLN2 silencing inhibits the proliferation of SW480 cells. Expression of TAGLN2 in a panel of CRC cell lines and NCM460 cells was detected by (A) western blotting and (B) RT-qPCR. Expression of TAGLN2 in SW480 cells was examined using (C) western blotting and (D) RT-qPCR following transfection with shRNA-TAGLN2. **P<0.01 and ***P<0.001. (E) Cell viability was evaluated using a Cell Counting Kit-8. ***P<0.001 vs. shRNA-NC. (F and G) Cell proliferation was assessed by EdU staining (scale bar, 50 µm). ***P<0.001. TAGLN2, transgelin 2; CRC, colorectal cancer; RT-qPCR, reverse transcription quantitative PCR; sh, short hairpin; NC, negative control; EdU, 5-ethynyl-2′-deoxyuridine.

Fig 3: Treatment with the STAT3 inhibitor HO-3867 reverses the positive effects of TAGLN2 overexpression on colorectal cancer cell proliferation. After TAGLN2 overexpression, mRNA and protein expression levels of TAGLN2 were measured by (A) reverse transcription-quantitative PCR and (B) western blotting, respectively. ***P<0.001. (C) Cell viability was assessed using a Cell Counting Kit-8. (D and E) EdU staining was used to evaluate the cell proliferation ability (scale bar, 50 µm). ***P<0.001 vs. OV-NC. ###P<0.001 vs. OV-TAGLN2. TAGLN2, transgelin 2; OV, overexpressing plasmid; NC, negative control; EdU, 5-ethynyl-2′-deoxyuridine.

Fig 4: Knockdown of TAGLN2 inhibits the migration and invasion of colorectal cancer cells. SW480 cell migration and invasion were respectively measured by (A and B) wound healing and (C and D) Transwell assays (scale bar, 100 µm). (E) Expression of MMP2 and MMP9 was measured by western blotting following TAGLN2 knockdown in SW480 cells. ***P<0.001. TAGLN2, transgelin 2; MMP, matrix metalloproteinase; sh, short hairpin; NC, negative control.

Fig 5: Overexpression of TAGLN2 enhances the expression of STAT3 downstream of ANXA2. (A) ANXA2 was predicted to be associated with STAT3 according to the Search Tool for the Retrieval of Interacting Genes/Proteins database. After overexpressing TAGLN2, the expression of ANXA2 was measured using (B) RT-qPCR and (C) western blotting. After knocking down ANXA2 in TAGLN2-overexpressing cells, the expression of ANXA2 was detected by (D) RT-qPCR and (E) western blotting. (F) Western blotting was used to examine the expression of STAT3 and p-STAT3. ***P<0.001. RT-qPCR, reverse transcription-quantitative PCR; TAGLN2, transgelin 2; ANXA2, annexin 2; STAT3, signal transducer and activator of transcription 3; sh, short hairpin; NC, negative control; OV, overexpressing plasmid; p, phosphorylated.