LINC00332 drives colorectal cancer cell migration and paclitaxel resistance

A long non-coding RNA called LINC00332 has emerged as a potential driver of colorectal cancer progression and resistance to the chemotherapy drug paclitaxel, according to a new study published in the journal Cell Division. Researchers from Mashhad University of Medical Sciences in Iran report that when they forced colorectal cancer cells to produce extra LINC00332, the cells activated two key cancer-promoting signaling pathways, underwent molecular changes associated with metastasis, migrated faster across laboratory dishes, and became markedly less responsive to paclitaxel treatment. The same RNA was also elevated in tumor tissue compared with healthy tissue from eighty patients, with the strongest increases seen in early-stage tumors.

Long non-coding RNAs, or lncRNAs, are RNA molecules that are transcribed from the genome but do not code for proteins. They make up a large share of the human transcriptome and regulate gene expression by interacting with DNA, other RNA molecules, and proteins. In cancer, individual lncRNAs can act as oncogenes that fuel tumor growth or as tumor suppressors that restrain it. Because they carry tissue-specific signatures and remain relatively stable in blood and plasma, they have attracted attention as candidates for non-invasive diagnostic markers and therapeutic targets. LINC00332, located on chromosome 13q14.11, had previously been described as a tumor suppressor in gastric cancer, where it inhibited Wnt/β-catenin signaling and reduced epithelial-mesenchymal transition, cell stemness, and cisplatin resistance. No role for the RNA in colorectal cancer had been reported before this study.

The research team, led by Meysam Moghbeli, Negin Taghehchian, Mahsa Palizkaran Yazdi, and Mohammad Reza Abbaszadegan, conducted the first investigation of LINC00332 in colorectal cancer. Patients who had received chemotherapy or radiotherapy before surgery, or whose clinical records were incomplete, were excluded from the study. Gene expression was measured using quantitative real-time PCR, with GAPDH serving as the internal control.

In the cell experiments, the researchers introduced a LINC00332 expression plasmid into HCT116 cells and confirmed a 14.35-fold increase in the RNA’s expression. The overexpression produced significant changes in two signaling networks with central roles in intestinal biology and cancer. In the NOTCH pathway, LINC00332 upregulated MAML1 by 1.84-fold, NOTCH1 by 1.10-fold, and NOTCH2 by 2.16-fold, which was accompanied by increased expression of the NOTCH target genes HEY1 and HEY2, at 1.65-fold and 1.77-fold respectively. In the WNT pathway, the RNA downregulated APC and GSK3β, two components of the destruction complex that normally degrades β-catenin, while raising LEF1, TCF7, LRP6, and β-catenin itself, the last by 3.21-fold. Together, these shifts point to enhanced β-catenin signaling and NOTCH pathway activation in the transfected cells.

The molecular changes extended to genes governing epithelial-mesenchymal transition, or EMT, a process in which epithelial cells lose their adhesive properties and acquire migratory, invasive characteristics. LINC00332 overexpression upregulated Vimentin, CDH2, Snail, ZEB2, and Slug, while downregulating CDH1 and OCLUDIN, markers of the epithelial state. The RNA also increased expression of matrix metalloproteinases, enzymes that degrade the extracellular matrix and support tissue remodeling and invasion: MMP10 rose 2.21-fold, MMP3 rose 2.42-fold, and MMP2 rose 1.23-fold. Consistent with these gene expression changes, a scratch wound-healing assay showed that LINC00332-transfected cells closed the wound significantly faster than non-transfected controls over 48 hours, with the difference reaching a p-value below 0.0001.

Using an MTT assay, the team measured the proliferation of HCT116 cells treated with 0.75 micromolar paclitaxel for 48 hours. Cells overexpressing LINC00332 showed significantly greater survival under paclitaxel treatment than non-transfected cells, again with a p-value below 0.0001. The resistance was associated with a 2.21-fold upregulation of ABCG2, an ATP-binding cassette transporter known to pump chemotherapeutic drugs out of cells.

In the patient cohort, which comprised 38 males and 42 females with a mean age of 57.30 years, quantitative analysis revealed significant upregulation of LINC00332 in tumor tissue compared with adjacent normal margins, with a p-value of 0.042. Overexpression was detected in 32.5 percent of patients and underexpression in 21.2 percent. Notably, the RNA was more highly expressed in early-stage tumors than in advanced ones, with stage I/II tumors showing mean expression of 0.81 compared with 0.06 in stage III/IV tumors. Early-stage tumors located in the transverse and left colon had significantly higher LINC00332 levels than those in the right colon. Tumors with perineural invasion showed significant upregulation compared with those without, at a p-value of 0.02, and lymph node-positive tumors also trended toward higher expression. Female patients and those with lower-grade, less invasive tumors also had higher expression levels.

The authors interpret these findings as evidence that LINC00332 acts as an oncogene in colorectal cancer, promoting EMT, cell migration, and paclitaxel resistance through WNT and NOTCH pathway activation. They propose that the RNA could serve as a diagnostic marker for early-stage disease, given its higher expression in stage I/II tumors, and that targeting it might improve paclitaxel response. However, they emphasize that the study is an early-stage, discovery-phase investigation. All functional experiments were conducted in a single cell line, HCT116, and colorectal cancer is a highly heterogeneous disease, so the results may not generalize to other colorectal cancer cell lines such as SW480, LoVo, or Caco-2. The paclitaxel resistance and migration findings were not tested in animal models, and the authors note that in vivo experiments with a tumor microenvironment, blood vessels, and an immune system would be needed to confirm the effects in a living system.

The study adds to a growing body of work implicating lncRNAs in colorectal cancer progression through WNT and NOTCH signaling. Previous research has identified lncRNAs that suppress these pathways, such as ADAMTS9-AS1, KIAA0125, LINC01550, and LINC00261, as well as others that potentiate them, including H19, SNHG1, and LINC01315. The simultaneous activation of WNT and NOTCH by LINC00332 observed in this study suggests a possible interaction between the two pathways during colorectal cancer progression, an idea the authors say warrants further investigation. For now, the findings position LINC00332 as a candidate biomarker and therapeutic target whose clinical value will depend on validation across diverse colorectal cancer subtypes and, ultimately, clinical trials.

Subject of Research: The role of the long non-coding RNA LINC00332 in colorectal cancer progression, epithelial-mesenchymal transition, and paclitaxel resistance

Article Title: Role of LINC00332 in colorectal cancer progression and paclitaxel resistance

Article References: Moghbeli, M., Taghehchian, N., Palizkaran Yazdi, M., & Abbaszadegan, M. R. (2025). Role of LINC00332 in colorectal cancer progression and paclitaxel resistance. Cell Division, 21(1), Article 3. https://doi.org/10.1186/s13008-025-00176-8

Image Credits: AI Generated

DOI: 10.1186/s13008-025-00176-8

Keywords: LINC00332, colorectal cancer, long non-coding RNA, paclitaxel resistance, WNT signaling, NOTCH signaling, epithelial-mesenchymal transition, HCT116, biomarker, drug resistance, EMT, early-stage diagnosis