Significance of E-cadherin and Vimentin as epithelial-mesenchymal transition markers in colorectal carcinoma prognosis

Association between the expression of epithelial-mesenchymal transition (EMT)-related markers and oncologic outcomes of colorectal cancer

BACKGROUND

Epithelial-mesenchymal transition (EMT) is a key step in the development of colorectal cancer (CRC) that confers metastatic capabilities to cancer cells. The present study aimed to assess the immunohistochemical (IHC) expression and impact of EMT markers, including E-cadherin, Vimentin, β-catenin, and SMAD4, on the oncologic outcomes of CRC.

METHODS

This was a retrospective review of 118 CRC patients. Tissue slides were retrieved from the slide archive and five tissue microarray construction blocks were constructed. IHC for E-cadherin, Vimentin, β-catenin, and SMAD4 was done. The main outcome was the association between abnormal marker expression and overall survival (OS), and disease-free survival (DFS).

RESULTS

Adenocarcinomas accounted for 71.2% of tumors, whereas 25.4% and 3.4% were mucinous and signet ring cell carcinomas. The rates of lymphovascular invasion and perineural invasion were 72.9% and 20.3%, respectively. There was a positive, significant correlation, and association between the four markers. Abnormal expression of E-cadherin was associated with significantly lower OS (p < 0.0001) and similar DFS (p = 0.06). Abnormal Vimentin expression was associated with a significantly higher rate of distant metastasis (p = 0.005) and significantly lower OS and DFS (p < 0.0001). Abnormal expression of β-catenin was associated with significantly lower OS (p < 0.0001) and similar DFS (p = 0.15). Abnormal expression of SMAD4 was associated with significantly lower OS and DFS (p < 0.0001). Abnormal expression of all four markers was associated with a higher disease recurrence, lower OS, and lower DFS.

CONCLUSION

Abnormal expression of each marker was associated with lower OS, whereas abnormal expression of Vimentin and SMAD4 only was associated with lower DFS.

Neurokinin B Administration Induces Dose Dependent Proliferation of Seminal Vesicles in Adult Rats

BACKGROUND

Neurokinin B; an endogenous decapeptide, mediates its reproductive physiological actions through gonadotropin releasing hormone. Despite the potential role of Neurokinin B on seminal vesicles, its effects on seminal vesicles in adult male mammals remain elusive. We aimed to investigate the potentials of variable doses of Neurokinin B, its agonist and antagonist on histomorphology and expression of NK3R on seminal vesicles, and secretory activity of seminal vesicles in adult male rats.

METHODS

Adult male Sprague Dawley rats (n=10 in each group) were administered intraperitoneally with Neurokinin B in three variable doses: 1 μg, 1 ηg and 10 ρg while, Senktide (Neurokinin B agonist) and SB222200 (Neurokinin B antagonist) in 1 μg doses consecutively for 12 days. After 12 days of peptide treatment, half of the animals (n=05) in each group were sacrificed while remaining half (n=05) were kept for another 12 days without any treatment to investigate treatment reversal. Seminal vesicles were dissected and excised tissue was processed for light microscopy, immunohistochemistry and estimation of seminal fructose levels.

RESULTS

Treatment with Neurokinin B and Senktide significantly increased while SB222200 slightly decrease the seminal vesicles weight, epithelial height and seminal fructose levels as compared to control. Light microscopy revealed increased epithelial height and epithelial folding as compared to control in all Neurokinin B and Senktide treated groups while decreased in SB222200. Effects of various doses of Neurokinin B, Senktide and SB222200 on seminal vesicles weight, epithelial height, seminal fructose levels and histomorphology were reversed when rats were maintained without treatments. Immuno-expression of Neurokinin B shows no change in treatment and reversal groups.

CONCLUSION

Continuous administration of Neurokinin B and Senktide effect positively while SB222200 have detrimental effects on cellular morphology, epithelial height and seminal fructose levels in seminal vesicles. Effects of peptide treatments depicted a reversal towards control group when rats were kept without any treatment.

Effect of silkworm pupae (Bombyx mori) protein on colon cancer in nude mice: inhibition of tumor growth, oxidative stress and inflammatory response

Silkworm pupa (bombyx mori) protein (SPP) is a potential therapeutic bioactive substance that has anti-tumor activity against breast, liver, and gastric cancers. The aim of this study was to investigate the antitumor effect of SPP on colon cancer nude mice. Using a subcutaneous tumor formation method, we validated the therapeutic effect of SPP on colon cancer nude mice in vivo. Results showed that SPP was cytotoxic to tumor cells. SPP could protect the liver of the nude mice by lowering hepatic oxidative stress and regulating serum inflammation levels by decreasing TNF-α and IL-2 levels while in-creasing INF-γ levels. In addition, diminished Ki-67 protein, enhanced cleaved caspase-3 protein, di-minished Vimentin, enhanced E-cadherin. These findings suggested that SPP's antitumor activity may be achieved by reducing inflammation, inhibiting tumor proliferation and metastasis, and inducing apoptosis in cancer cells. In the future, SPP could be used as an anticancer drug, potentially providing a new source of drugs for the treatment of colon cancer.

A hybrid approach to assess the structural impact of long noncoding RNA mutations uncovers key NEAT1 interactions in colorectal cancer

Long noncoding RNAs (lncRNAs) are emerging players in cancer and they entail potential as prognostic biomarkers or therapeutic targets. Earlier studies have identified somatic mutations in lncRNAs that are associated with tumor relapse after therapy, but the underlying mechanisms behind these associations remain unknown. Given the relevance of secondary structure for the function of some lncRNAs, some of these mutations may have a functional impact through structural disturbance. Here, we examined the potential structural and functional impact of a novel A > G point mutation in NEAT1 that has been recurrently observed in tumors of colorectal cancer patients experiencing relapse after treatment. Here, we used the nextPARS structural probing approach to provide first empirical evidence that this mutation alters NEAT1 structure. We further evaluated the potential effects of this structural alteration using computational tools and found that this mutation likely alters the binding propensities of several NEAT1-interacting miRNAs. Differential expression analysis on these miRNA networks shows upregulation of Vimentin, consistent with previous findings. We propose a hybrid pipeline that can be used to explore the potential functional effects of lncRNA somatic mutations.

Mechanism of Extracellular Vesicle Secretion Associated with TGF-β-Dependent Inflammatory Response in the Tumor Microenvironment

Extracellular vesicles (EVs) serve as central mediators in communication between tumor and non-tumor cells. These interactions are largely dependent on the function of the endothelial barrier and the set of receptors present on its surface, as endothelial cells (ECs) are a plenteous source of EVs. The molecular basis for EV secretion and action in the tumor microenvironment (TME) has not been fully elucidated to date. Emerging evidence suggests a prominent role of inflammatory pathways in promoting tumor progression and metastasis. Although transforming growth factor β (TGF-β) is a cytokine with strong immunomodulatory and protective activity in benign and early-stage cancer cells, it plays a pro-tumorigenic role in advanced cancer cells, which is known as the "TGF-β paradox". Thus, the aim of this review is to describe the correlation between EV release, TGF-β-dependent inflammation, and dysregulation of downstream TGF-β signaling in the context of cancer development.

Hepcidin Upregulation in Colorectal Cancer Associates with Accumulation of Regulatory Macrophages and Epithelial-Mesenchymal Transition and Correlates with Progression of the Disease

Advanced, metastatic colorectal cancer (CRC) is associated with high rate of mortality because of its poor responsiveness to chemotherapy/immunotherapy. Recent studies have shown that hepcidin, a peptide hormone produced mainly by hepatocytes, is expressed by and enhances the growth of tumor cells. We here assessed whether hepcidin expression helps identify subsets of CRC with advanced and aggressive course. By integrating results of in vitro/ex vivo studies with data of bioinformatics databases, we initially showed that hepcidin RNA and protein expression was more pronounced in tissue samples taken from the tumor area, as compared to the macroscopically unaffected, adjacent, colonic mucosa of CRC patients. The induction of hepcidin in the colonic epithelial cell line HCEC-1ct by interleukin (IL)-6, IL-21 and IL-23 occurred via a Stat3-dependent mechanism and, in primary CRC cells, hepcidin co-localized with active Stat3. In CRC tissue, hepcidin content correlated mainly with macrophage accumulation and IL-10 and CD206 expression, two markers of regulatory macrophages. Consistently, both IL-10 and CD206 were up-regulated by hepcidin in blood mononuclear cells. The highest levels of hepcidin were found in metastatic CRC and survival analysis showed that high expression of hepcidin associated with poor prognosis. Moreover, hepcidin expression correlated with markers of epithelial-to-mesenchymal transition and the silencing of hepcidin in CRC cells reduced epithelial-to-mesenchymal transition markers. These findings indicate that hepcidin is markedly induced in the advanced stages of CRC and suggest that it could serve as a prognostic biomarker in CRC.

Inhibition of α(1,6)fucosyltransferase: Effects on Cell Proliferation, Migration, and Adhesion in an SW480/SW620 Syngeneic Colorectal Cancer Model

The present study explored the impact of inhibiting α(1,6)fucosylation (core fucosylation) on the functional phenotype of a cellular model of colorectal cancer (CRC) malignization formed by the syngeneic SW480 and SW620 CRC lines. Expression of the FUT8 gene encoding α(1,6)fucosyltransferase was inhibited in tumor line SW480 by a combination of shRNA-based antisense knockdown and Lens culinaris agglutinin (LCA) selection. LCA-resistant clones were subsequently assayed in vitro for proliferation, migration, and adhesion. The α(1,6)FT-inhibited SW480 cells showed enhanced proliferation in adherent conditions, unlike their α(1,6)FT-depleted SW620 counterparts, which displayed reduced proliferation. Under non-adherent conditions, α(1,6)FT-inhibited SW480 cells also showed greater growth capacity than their respective non-targeted control (NTC) cells. However, cell migration decreased in SW480 after FUT8 knockdown, while adhesion to EA.hy926 cells was significantly enhanced. The reported results indicate that the FUT8 knockdown strategy with subsequent selection for LCA-resistant clones was effective in greatly reducing α(1,6)FT expression in SW480 and SW620 CRC lines. In addition, α(1,6)FT impairment affected the proliferation, migration, and adhesion of α(1,6)FT-deficient clones SW480 and SW620 in a tumor stage-dependent manner, suggesting that core fucosylation has a dynamic role in the evolution of CRC.

MicroRNA-1298-5p inhibits the tumorigenesis of breast cancer by targeting E2F1

Studies performed in the last two decades have identified microRNA (miR)-1298-5p to display tumor-suppressive functions in several types of malignancy. In addition, the regulatory role of E2F transcription factor 1 (E2F1) has been reported in multiple types of cancer, including breast cancer (BC). However, whether miR-1298-5p participates in BC progression and whether a regulatory association exists between miR-1298-5p and E2F1 remains to be explored. The present study aimed to determine the role of miR-1298-5p and its interaction with E2F1 in BC. The expression of miR-1298-5p and E2F1 was examined by reverse transcription-quantitative PCR and western blot assays. The viability and proliferative capacity of BC cells were evaluated by Cell Counting Kit-8 and 5-bromo-2′-deoxyuridine assays, respectively. The apoptotic rate was assessed by the caspase-3 activity assay and flow cytometry; the protein expression levels of vimentin and E-cadherin were evaluated by western blotting. In addition, the adhesive and migratory abilities of BC cells were determined by conducting cell adhesion and wound healing assay, respectively. The target relationship between miR-1298-5p and E2F1 was validated by the luciferase reporter assay. The results of the present study revealed that the levels of miR-1298-5p were downregulated in BC tissues and cells compared with those in normal breast tissues and cells, respectively. In addition, miR-1298-5p was demonstrated to inhibit the proliferation, adhesion and migration of BC cells and to promote BC cell apoptosis. E2F1 was verified as a target gene of miR-1298-5p using the luciferase reporter assay. Additionally, E2F1 exhibited an opposite expression pattern compared with that of miR-1298-5p in BC tissues. Furthermore, the downregulation of miR-1298-5p in BC cells was reversed by silencing E2F1. Overall, the results of the present study suggested that miR-1298-5p repressed BC cell proliferation, adhesion and migration, and enhanced BC cell apoptosis by downregulating E2F1.

MicroRNA-325-3p contributes to colorectal carcinoma by targeting cytokeratin 18

Colorectal carcinoma (CRC) is one of the most common malignant tumors. The present study aimed to investigate a non-invasive molecular marker that can evaluate the diagnosis and potential molecular mechanism of CRC. Microarray assays and reverse transcription-quantitative PCR analysis demonstrated that microRNA (miR)-325-3p expression was significantly increased in both tissues and serum samples of patients with CRC. In addition, miR-325-3p expression in the tissues and serum was significantly associated with differentiation, TNM stage and lymph node metastasis. The results of the dual-luciferase reporter assay and western blot analysis revealed that cytokeratin 18 (CK18) is a target gene of miR-325-3p. Furthermore, treatment with transforming growth factor (TGF)-β increased miR-325-3p expression in a time-dependent manner. Conversely, TGF-β decreased CK18 expression at 48 and 72 h. Western blot analysis demonstrated that TGF-β1 significantly decreased the expression of the epithelial marker, CK18, and increased the expression of the mesenchymal markers, α-SMA and vimentin. Notably, these effects were reversed following inhibition of miR-325-3p expression. Taken together, the results of the present study suggest that miR-325-3p is a key regulator of TGF-β-induced CK18 downregulation. Thus, elevated levels of miR-325-3p is an important factor affecting epithelial-to-mesenchymal transition, and is likely to be a molecular marker in the progression of CRC and act as a potential therapeutic target.