LINC01296/miR-26a/GALNT3 axis contributes to colorectal cancer progression by regulating O-glycosylated MUC1 via PI3K/AKT pathway

A total of 36 previously diagnostic CRC patients who received surgical operation at the First Affiliated Hospital of Dalian Medical University were included. CRC patients accepted informed consent, which was approved by the Ethics Committee of the First Affiliated Hospital of Dalian Medical University (YJ-KY-FB-2016-16). In accordance with the International Union against Cancer (UICC), the samples were identified CRC tissues and nontumor tissues, and further identified different stages (stageI, II, III and IV) based on the histopathological evaluation. The samples were maintained in liquid nitrogen.

The human CRC cell lines SW620, SW480, HCT-8, 5-FU-resistant HCT-8 cells (HCT-8/5-FU) and LoVo were obtained from KeygenBiotech Co. Ltd. (Nanjing, China), which was recently authenticated as truly CRC cell lines. SW620 and SW480 were cultured in Leibovitz’s L-15 (Gibco, Grand Island, NY) medium contained 10% in activated fetal bovine serum (Gibco, Grand Island, NY). 5-FU was added to LoVo cell culture in stepwise increasing concentrations for over 6 months, namely LoVo/5-FU. HCT-8/5-FU and LoVo/5-FU were maintained in RPMI1640 supplementd with 114.7 μM and 107.0 μM 5-FU, respectively. CRC cells were incubated at 37 °C containing 5%CO₂. All cells lines were routinely tested for mycoplasma, which were shown to be negative.

Total RNA was extracted by RNeasy Mini Kit (Qiagen, Valencia, CA), and cDNA was then synthesized by QuantiTect Reverse Transcription Kit (Qiagen, Valencia, CA). The qRT-PCR was performed under an ABI Prism7500 fast real-time PCR system with mixing a QuantiTect SYBR Green PCR Kit (Qiagen, Valencia, CA). Relative RNA expression was calculated by ΔΔCt method with normalization to U6. The primers for GALNT3 are F: 5’-AAAGCGTTGGTCAGCCTCTATGTC-3′ and R: 5’-TGGATGTTGTGCCGAATTTCA-3′, and the primers for GAPDH were F: 5’-CTCCTCCACCTTTGACGCTG-3′ and R: 5’-TCCTCTTGTGCTCTTGCTGG-3′.

Cell protein was collected by RIPA lysis buffer (KeyGEN, Nanjing, China) containing 1 nM PMSF (Biotool, Houston, TX, USA). 20 μg protein per well was electrophorsed in 10% SDS-PAGE gels and then transferred to polyvinylidene difluoride membranes (Millipore, Bedford, MA, USA), and incubated with different primary antibodies, including GALNT3 (16716–1-AP, Proteintech, China), caspase3 (ab13847, Abcam, the UK), cleaved caspase3 (ab13585, Abcam, the UK), PARP (ab74290, Abcam, the UK), cleaved PARP (ab4830, Abcam, the UK), MUC1 (ab15481, Abcam, the UK), PI3K-p110α (21890–1-AP, Proteintech, China), p-AKT 308 (AP3743a, Abgent, China), p-AKT 473 (AP3434a, Abgent, China), AKT (ab8805, Abcam, the UK), NF-κB (AP50006, Abgent, China) and GAPDH (AP7873a, Abgent, China), at 4 °C overnight. The membrane was treated with anti-rabbit IgG at 37 °C for 2 h. All bands were detected by an ECL Western blot kit (Thermo Fisher Scientific, USA) and analyzed by Lab Works (TM ver4.6, UVP, Bio Imaging Systems, NY, USA). GAPDH was used as control.

PCR production of GALNT3 ampliation was cloned into pmirGLO vector (Promega). MiR-26a mimic, inhibitor and miR-NC were synthesized by GenePharma Co.Ltd. (Suzhou, China). Linc01296 pcDNA3.1 vector (linc01296), LV-NC, LV-linc01296, silinc01296, shlinc01296, siSCR and shSCR were obtained from GenePharma Co.Ltd. (Suzhou, China). The transfection assay was conducted with Lipofectamine 3000 (Invitrogen, Carlsbad, CA, USA). The transfected efficiency was measured by qRT-PCR.

A pmirGLO Dual-Luciferase miRNA Target Expression Vector was purchased from GenePharma Co.Ltd. (Suzhou, China). Firefly luciferase functioned as primary reporter to regulate mRNA expression, and renilla luciferase was used as a normalized control. Co-transfection was conducted and the dual luciferase reporter assay system (Promega) was utilized. The mean luciferase intensity was normalized to renilla luciferase. Data were shown as the mean value ± SD and each experiment was performed thrice.

Cell proliferation assay was conducted by using cell counting kit-8 (CCK-8; Dojindo, Japan). Cells (1 × 10³ per well) were plated into 96-well plate with the corresponding medium. 11 μL CCK8 were added for 4 h. The spectrometric absorbance was measured by microplate reader (Model 680; Bio-199 Rad, Hercules, CA, USA) at 490 nm.

The chemoresistance to 5-FU was detected by CCK-8. Different concentration of 5-FU was added into 96-well plate. The absorbance was then measured to evaluate the chemoresistance to 5-FU. Each experiment was performed thrice.

Single-cell suspension was obtained and then seeded in 6-well plate (1 × 10³ per well). The medium was changed every 4 days. Twenty-one days later, the foci were formed obviously. The colonies were fixed by 4% paraformaldehyde for 20 min, and then stained with 0.2% crystal violet. The colonies were photographed and counted.

Cells were cultured in Boyden chambers containing a transwell membrane filter (Corning, New York, USA), and in serum-free medium overnight. Gelatin and matrigel were used to coat the filter, and 5 × 10⁴ cells were suspended on top. On the other side, L-15 with 10%FBS was put in the lower part of the chamber. The upper side cells were removed by a cotton swab. The invading cells were counted to estimate the invasive capacity.

CRC cells were incubated with different concentration of 5-FU for 48 h. 2 × 10³ cells were collected and resuspended in 100 μL binding buffer. Annexin V and propidium iodide (BD, Franklin Lakes, NJ, USA) were used to stain for 10 min avoiding light and 400 μL binding buffer was added into the cell suspension. The apoptotic cells were detected by FACS Calibur (Becton-Dickinson, CA, USA).

Cells with corresponding treatment were collected (5 × 10⁵). After incubation with 5%BSA, the cells were incubated with FITC-VVA (Vector Laboratories Inc., Burlingame, CA, USA) for 60 min. The FITC fluorescence intensity was detected by FACS Calibur.

CRC cells were fixed with 4% paraformaldehyde for 20 min and treated with 0.2% Triton X-100 for 3 min. After incubation with 5% BSA, the primary antibody was added overnight at 4 °C, and the secondary antibody was treated. The cells were stained by 4, 6-diamino-2-phenylindole (DAPI, Sigma-Aldrich, St Louis, MO, USA) for nuclear staining. The pictures were obtained with fluorescence microscope (OLYPAS).

Human CRC samples and xenograft tumors were performed on paraffin-embedded sections. The slides were treated with drying, deparaffining and rehydrating. The slides were immersed with 3% hydrogen peroxide and labeled with antibodies overnight. The slides were stained with the secondary streptavidin-horseradish peroxidase-conjugated antibody (Santa Cruz Biotech, Santa Cruz, CA). The slides were then counterstained with hematoxylin for 30s and cover slipped.

TUNEL assay was carried out to measure the fragmented DNA of apoptotic cells. Apoptotic cells were fixed by 4% formaldehyde for 25 min, and permeabilized by 0.2% TritonX-100 for 5 min. Then the cells were equilibrated with 100 μL Equilibration buffer for 10 min. Cells were labeled with 50 μL TdT reaction mix at 37 °C. SSC buffer was used to stop the reaction. The images were pictured by fluorescence microscopy.

JC-1 (5, 5, 6, 6-tetrachloro-1, 1, 3, 3-tetraethylbenzimidazolylcarbocyanineiodide, KeyGen, China) was used to measure the variation of mitochondrial membrane potential. The cells were stained with 5 μM JC-1 for 30 min at 37 °C and pictured with the fluorescence microscopy.

The Magna RIPTM RNA Binding Protein Immunoprecipitation Kit (Millipore, USA) was used to conduct RNA immunoprecipitation (RIP) assay. The endogenous miR-26a which combined with linc01296 was pulled down. The cell lysis were incubated in RIP immunoprecipitation buffer containing magnetic bead conjugated with human anti-Ago2 antibody (Millipore). The protein was digested by proteinase K to obtain the immunoprecipitated RNA. The qRT-PCR assay was conducted to detect the purified RNA concentration.

The cells were lysed and the extracts were treated with 50 μl VVA-agarose at 4 °C with gentle rotation for 16 h. Then the samples were washed by the eluting solution and further suffered the western blot analysis.

The experiments were approved by the Committee on the Ethics of Animal Experiments of the Dalian Medical University, China. No blinding of experiment groups was conducted. The 4-week-old male nude mice were obtained from the the Model Animal Research Institute of Nanjing University.

Liver metastasis model was built as follows. Four-week-old male nude mice were randomly used to build the liver metastasis model under anesthetizing (n = 6 animals per group). For randomization, the nude mice was then numbered, which further chosen for each group. The endpoints of in vivo metastasis experiments were based on the presence of clinical signs of liver metastasis, weight loss, the appearance of ascites and energielos with reduced action. Animals were culled with the above signs or 28 days after surgery based on specific experimental designs. The spleen was exposed and injected with 5 × 10⁶ CRC cell, and this procession sustained at least 5 min. The wound was sutured carefully. The nude mice were sacrificed 28 days later, and the liver and the spleen were collected and photographed.

Xenografts model was established as follows. 1 × 10⁷ GFP labelled CRC cells were injected subcutaneously into the right flank of each nude mouse, respectively. The mouse were randomly divided into control and treatment groups (n = 6 animals per group) when the mice bearing palpable tumors. The groups received DMSO, 5-FU or LY294002, respectively. The endpoints of in vivo xenografts experiments were based on the presence of weight loss, tumor volume higher than 4cm³ and energielos with reduced action. Animals are humanely culled with the above signs or 21 days after surgery based on specific experimental designs. Twenty-one days later, the X-Ray photo and fluorescent photo were captured to reveal the tumor volume in vivo. The photos were taken by in-vivo Imaging System of Dalian Medical University. Then the mice were humanely killed and the tumors were isolated, measured and photographed. The tumor weight and volume was recorded, and under two-tailed Student’s t test statistical analysis. The experiments were approved by the Committee on the Ethics of Animal Experiments of the Dalian Medical University, China.

According to our previous microarray analysis based on SW620 and SW480 cell lines [24], linc01296 showed an increasing tendency in SW620 cells with high metastasis potential. To validate this conclusion, we examined linc01296 expression between 36 pairs of CRC tissues and the corresponding adjacent tissues. In accordance with the microarray results, linc01296 showed a higher level in tumor tissues. Further investigation was shown in Fig. 1b, overexpression of linc01296 was confirmed in SW620 and 5-FU resistant CRC cells (HCT-8/5-FU cells and LoVo/5-FU cells). Linc01296 level was closely correlated with advanced CRC stages, and CRC patients on stage III and IV exhibited a higher linc01296 level (Fig. 1c). Moreover, linc01296 was also identified to connect with metastasis of CRC patients, including node metastasis, liver metastasis and other distant metastasis (Fig. 1d). Kaplan-Meier analysis was used to analyze the correlation between linc01296 expression and the overall survival rate. As shown in Fig. 1e, CRC patients with high linc01296 level lived with a poor prognosis than those with lower level. To better understand the role of linc01296 in CRC progression, we manipulated the expression of linc01296 by transfecting linc01296 or silinc01296 in CRC cell lines. The transfected efficiency was measured (Fig. 1f, g). These data indicated that high linc01296 level might correlate with the CRC progression and associate with the poor clinical prognosis.

To evaluate the possible role of linc01296 involved in proliferation, CCK8 assays were used to identify the growth rate of CRC cells. As shown in Fig. 2a, inhibition of linc01296 attenuated CRC cell viability. The colony formation assay also proved a decreased tendency in the cells transfected with silinc01296 (Fig. 2b). 5-Ethynyl-2′-deoxyuridine (Edu) showed a remarkable function in evaluating cell proliferation, which usually participated in DNA synthesis. The merged images were presented, and indicated that knockdown of linc01296 reduced CRC cells proliferation (Fig. 2c). Moreover, as a key indicator of cell proliferation, Ki67 was also measured by immunofluorescence staining. In accordance with Edu staining, Ki67 expressed a weaken fluorescence intensity in CRC cells transfected with silinc01296 (Fig. 2d). As shown in Fig. 2e, depletion of linc01296 decreased the migratory and invasive capability of SW620 cell compared to the cell transfected with siSCR. SW480, HCT-8 and LoVo cells were suffered with vector and linc01296, which were further underwent CCK8 assays. Cells transfected with linc01296 showed higher growth rate than the cells transfected with vector (Fig. 2f). Overexpressed linc01296 in CRC cells promoted the colony formation (Fig. 2g) and DNA synthesis (Fig. 2h). Upregulation of linc01296 promoted Ki67 concentration of transfected CRC cells (Fig. 2i). On the contrary, overexpressed linc01296 led to the enhanced aggressiveness (Fig. 2j). Thus, linc01296 level significantly affected proliferation and aggressiveness of CRC cell lines.

CCK8 assays were performed to confirm the reversal chemoresistance caused by silinc01296 (Fig. 3a), the OD values were significantly decreased in CRC cells transfected silinc01296. The IC₅₀ values were then calculated to intuitively measure the differential chemoresistance between silinc01296 and siSCR transfected CRC cells (Fig. 3b). The control cells and 5-FU resistant CRC cells transfected with siSCR showed no variation in IC₅₀ values. However, decreased linc01296 level significantly attenuated the IC₅₀ values. In response to 5-FU treatment, siLinc01296–5-FU reisitant cells showed a reductive colony formation numbers (Fig. 3c). As depicted in Fig. 3d, depletion of linc01296 drastically enhanced apoptotic cell rates, indicating the potential role of silinc01296 in inducing CRC cell apoptosis. Mitochondrial membrane potential damage was a key event during the occurrence of apoptosis, which was caused by the activation of caspases, then the cytochrome c release into cytosol. In this study, JC-1 content was detected by immunofluorescence staining. The results showed that downregulated linc01296 resulted in the lower potential, indicating the apoptosis caused by downregulated linc01296 (Fig. 3e). High fluorescence intensity was captured during the apoptosis occurred after knocking down linc01296 by fluorescence microscope (Fig. 3f). As a key modulator of apoptosis, caspase3 plays an important role in 5-FU induced CRC cells apoptosis. With 5-FU treatment, cells transfected with silinc01296 expressed low caspase3 and PARP levels, and increased levels of cleaved caspase3 and cleaved PARP by western blot (Fig. 3g). In the transfected HCT-8 and LoVo cells, the resistance to 5-FU was assessed by CCK8 (Fig. 3h) and IC₅₀ values (Fig. 3i), indicated that linc01296 strengthened the resistance to 5-FU treatment. Enhanced linc01296 promoted colony formation numbers of transfected CRC cells (Fig. 3j). HCT-8 and LoVo cells transfected with linc01296 performed more resistant to 5-FU treatment, showing decreased apoptosis rate (Fig. 3k). JC-1 staining also showed an increased J-aggregates in CRC cells transfected with linc01296 (Fig. 3l). Moreover, TUNEL assay showed less occurrence of apoptosis after transfecting linc01296 (Fig. 3m). Altered level of caspase3, cleaved caspase3, PARP and cleaved PARP were also detected by western blot, suggesting that apoptosis indeed occurred (Fig. 3n). Thus, alteration of linc01296 in CRC cells exhibited changeable proliferation, migration and chemoresistance to 5-FU.

Bioinformatic analysis predicts that miR-26a is closely associated with linc01296. Interestingly, miR-26a showed certain difference between CRC tissues and the adjacent tissues (Fig. 4a). Furthermore, SW620 and 5-FU resistant CRC cells revealed decreased miR-26a level (Fig. 4b). The negative correlation was found between linc01296 and miR-26a expression (Fig. 4c). According to the bioinformatic analysis, we determined the predicted binding sites. Dual-luciferase reporter gene assay confirmed that miR-26a was a direct target of linc01296 (Fig. 4d). According to our previous results, GALNT3 functioned as a downstream of linc01296. GALNT3 expression of CRC tissues was analyzed by qRT-PCR (Fig. 4e) and measured by IHC staining. Higher GALNT3 mRNA level was determined in CRC tumor tissues than the adjacent nontumor tissues. GALNT3 expression of CRC cell lines was also determined by qRT-PCR and western blot. As shown in Fig. 4f, SW620 and 5-FU resistant CRC cells showed high GALNT3 level. Moreover, immunofluorescence staining also confirmed high GALNT3 expression in SW620, HCT-5-FU and LoVo/5-FU cells (Fig. 4g). The negative association of miR-26a and GALNT3 was calculated (Fig. 4h). Dual-luciferasereporter gene assay convinced miR-26a directly target GALNT3 (Fig. 4i). Argonaute 2 (Ago2) protein could bind miRNAs and lncRNAs. As shown in Fig. 4j, linc01296 and miR-26a enriched in Ago2 pellet compared to the IgG immunoprecipitates. RIP assay illustrated that linc01296 and miR-26a existed in CRC cell lines, which corroborated the correlation between linc01296 and miR-26a. As shown in Fig. 4k, upregulation of linc01296 promoted GALNT3 expression determined by qRT-PCR. Western blot also revealed a higher GALNT3 level in CRC cells transfected with linc01296 compared to the control. Downregulation of linc01296 presented opposite tendency by qRT-PCR (Fig. 4k) and western blot (Fig. 4l). Co-transfection of miR-26a and linc01296 was conducted to further measure the altered GALNT3. Cells transfected with miR-26a mimics showed decreased GALNT3 level by qRT-PCR (Fig. 4m), on the contrary, high linc01296 level enhanced GALNT3 expression. Interestingly, co-transfected linc01296 and miR-26a mimic into CRC cells revealed an attenuation of GALNT3 level, indicated the reversal effect of miR-26a on the upregulated GALNT3 caused by linc01296. Similar results were also detected by western blot in CRC cell lines. Increased GALNT3 was detected in the cells transfected with miR-26a inhibitor, and knockdown of linc01296 decreased GALNT3 expression in CRC cell lines (Fig. 4n). Moreover, co-transfection of miR-26a inhibitor and silinc01296 regained high GALNT3 level compared to the group transfected silinc01296 only, demonstrated the miR-26a inhibitor reversal effect of silin01296. These results demonstrated that miR-26a functioned as a target of linc01296, and targeted GALNT3 in CRC progression.

To identify the molecular mechanism of CRC progression, linc01296 and miR-26a expression were modulated in CRC cell lines. Vicia villosa agglutinin (VVA) recognized Tn antigen (GalNAc-O-Ser/Thr) generated by GalNAc transferase, and detected by flow cytometry. A significant difference in O-glycosylation in CRC cell lines was estimated by fluorescence intensity of VVA (Fig. 5a). High expression of GALNT3 was corresponding with high fluorescence intensity of VVA lectin in CRC cell lines. The growth rate was lower in the cells transfected with silinc01296, and much higher in the cells transfected with miR-26a inhibitor than the control groups (Fig. 5b). Colony formation assay also depicted higher numbers than the control group, and the colony formation ability was regained with transfected miR-26a inhibitor (Fig. 5c). As shown in Fig. 5d, lower aggressiveness was shown in SW620 cells transfected with silinc01296, which was enhanced in group with miR-26a inhibitor. However, co-transfected silinc01296 and inmiR-26a depicted a revised migration and invasion than the cell only transfected with silinc01296, suggesting that miR-26a might reverse the migratory ability of SW620. CCK8 assay showed that miR-26 inhibitor promoted chemoresistance to 5-FU, and silinc01296 facilitated the cells sensitive again (Fig. 5e). The IC₅₀ values showed similar tendency (Fig. 5f). Colony formation assay further proved 5-FU-resistant cell lines had a variable degree in response to 5-FU treatment (Fig. 5g). The apoptotic rate of silinc01296 cells exhibited less survival, and knockdown of miR-26a exhibited more survival. Moreover, the apoptotic cells were decreased when the cells treated with silinc01296 and miR-26a together relative to cells treated with silinc01296 (Fig. 5h). In brief, miR-26a reversed the anti-tumor effect of silinc01296 by regulating GALNT3 expression in CRC progression.

As shown in Fig. 5i, altered terminal O-glycosylation in CRC cell lines was revealed by fluorescence intensity on VVA. Cell viability was significantly increased in CRC cells transfected with linc01296 (Fig. 5j). Similarly, the viability was reversed with co-transfection with miR-26a. In brief, miR-26a rapidly reversed the cell growth rate by enhancing linc01296. Colony formation assay also depicted similar tendency (Fig. 5k). As shown in Fig. 5l, the migratory and invasive abilities were reconsolidated by transfection with miR-26a mimic. As shown in Fig. 5m, cells with high linc01296 level were more resistant to 5-FU, while co-transfected linc01296 and miR-26a resumed 5-FU sensitivity. We further detected the IC₅₀ values (Fig. 5n). With 5-FU treatment, the colony formation number was counted (Fig. 5o). Acquired chemosensitivity was also confirmed by flow cytometry analysis. As shown in Fig. 5p, HCT-8 transfected with linc01296 was less sensitive to 5-FU treatment, and HCT-8 cells transfected with miR-26a showed more sensitive to 5-FU than the control groups. MiR-26a performed a reversal ability to make CRC cells more sensitive to 5-FU. Thus, miR-26a indeed affected the malignancy by regulating linc01296, and further affect the CRC progression via regulating GALNT3.

As a key enzyme of O-glycosylation, GALNT3 performed significant alteration during CRC progression. To further clarify the internal mechanism, O-glycosylated glycan-binding lectin VVA agarose pull-down was performed and analyzed for western blot (Fig. 6a). The VVA-precipitated MUC1 was upregulated in the cells transfected with GALNT3 (SW480 and HCT-8) compared to the control. In contrast, SW620 and HCT-8/5-FU cells transfected with shGALNT3 revealed decreased VVA-binding MUC1 level. However, the total extracted proteins of CRC cell lines showed no changes, illustrating the altered O-glycosylation of CRC cells. As shown in Fig. 6b, the PI3K/AKT signaling was inactivated by MUC1-blocking with the specific antibody in HCT-8 and HCT-8/5-FU cells. In combination with VVA, the signaling cascade was further suppressed. Moreover, upregulation of GALNT3, contributed to the enriched O-glycosylation, further activated PI3K/AKT cascade (Fig. 6c). Knockdown GALNT3 inhibited the activation of PI3K/AKT pathway. Manipulation of linc01296 and miR-26a could affect expression of the main molecules of PI3K/AKT pathway. Simultaneously, as an effective inhibitor of PI3K/AKT pathway, LY294002 further confined the signaling cascade in HCT-8/5-FU cells (Fig. 6d). As shown in Fig. 6e, upregulation of miR-26a inhibited PI3K/AKT signaling activity in HCT-8 cells. Overexpressed linc01296 triggered the activation of the pathway. However, co-transfection of miR-26a and linc01296 in HCT-8 cells significantly reversed the activity of the pathway in relation to the cells transfected with miR-26a or linc01296. Similarly, co-transfection of inmiR-26a and silinc01296 in HCT-8/5-FU cells revealed a reversal effect on the phosphorylated status in the cells transfected inmiR-26a or silinc01296 only. Moreover, regulation of miR-26a and linc01296 affected GALNT3 level, which in consequence modified the O-glycosylation on MUC1. These results provided the novel notion that linc01296 and miR-26a exhibited regulatory role in O-glycosylation of MUC1 via PI3K/AKT signaling cascade.

To further confirm whether linc01296 involved in CRC liver metastasis and chemoresistance, the nude mice model was built. The liver metastasis of CRC model was conducted to clarify the effect of linc01296. Shlinc01296 decreased the tumor volume of liver metastasis (Fig. 7a up panel), and overexression of linc01296 facilitated the liver metastasis of CRC (Fig. 7a down panel). As shown in Fig. 7b, GALNT3 expressed at a lower level in the model built by shlinc01296 transfected SW620 cells, and Ki67 also showed a lower level than the control group. Upregulation of linc01296 promoted the liver metastasis degree, in the meantime, overexpression of GALNT3 and Ki67 were also determined by IHC staining. To further confirm the CRC cell tumorigenesis, and the effect of concomitant application of shlinc01296, 5-FU or LY294002 in HCT-8/5-FU cells, green fluorescent protein applied for tumor-bearing nude mouse in vivo. Twenty-one days later, shlinc01296 sensitized 5-FU-resistant CRC cells compared to the control group. Moreover, inhibition of PI3K/AKT pathway decreased the tumor volume (Fig. 7c). IHC staining was used to identify the involvement of GALNT3 in CRC progression (Fig. 7d). Ki67 staining confirmed the lower proliferation in the mediation of shlinc01296 and LY294002. Tumor weight and volume were also recorded (Fig. 7e, f). Thus, the procession of liver metastasis and chemoresistance to 5-FU could efficiently reverse by shlinc01296 or combination with 5-FU and LY294002, which offered promising therapeutic targets.