Absence of EpCAM in cervical cancer cells is involved in sluginduced epithelial-mesenchymal transition

Lipidomic profiling of triple-negative breast cancer cells reveals distinct metabolic signatures associated with EpCAM expression

Lipid metabolism is essential at all stages of cancer progression, particularly for triple-negative breast cancer (TNBC) the deadliest cancer subtype for women patients. TNBC cells exhibit significant metabolic heterogeneity, which contributes to their aggressive behavior. Epithelial-to-mesenchymal transition (EMT), a key step in metastasis, is associated with distinct lipid profiles, where the epithelial cell adhesion molecule (EpCAM) was found to be decreased along the transition. To understand this link, we employed lipidomic profiling of the TNBC cell line SUM149PT, which exhibits high variability in EpCAM, an epithelial marker. Using EpCAM levels to categorize cells with high and low EpCAM expression using fluorescence-activated cell sorter, we performed targeted mass spectrometry analysis of various lipid classes (glycerophospholipids, glycerolipids, lysophospholipids, and sphingolipids) by a hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS)-based screening method. After correcting for cell size, we identified a unique lipid profile associated with each EpCAM expression level. Notably, cells with higher EpCAM expression displayed lower levels of lysophosphatidylethanolamine (LPE). This finding suggests a potential role for LPE in the regulation of EMT in TNBC.

ZNF281 Facilitates the Invasion of Cervical Cancer Cell Both In Vivo and In Vitro †

Background: Cervical cancer is the fourth most common cancer among women worldwide. The zinc finger transcription factor 281 (ZNF281)/ZBP-99 protein specifically binds to GC-rich DNA sequences and regulates gene expression, and it has been shown to promote tumor progression. In this study, we aim to investigate the function and molecular mechanism of ZNF281 in uterine cervical carcinoma. Methods: We conducted immunohistochemistry and Western blot assays to determine the expression of ZNF281 in eight human cervical cancer tissues. And, xenograft experiments involving the injection of HeLa cells into nude mice was used to determine the function of ZNF281 on proliferation. Transwell assays were used to detect the migration and invasion of HeLa cells after indicated that ZNF281 overexpression. Results: Our results indicated that ZNF281 protein levels were higher in cervical cancer tissues compared to normal cervical tissues. Additionally, ZNF281 was expressed in human cervical carcinoma cell lines, including HeLa, SiHa, C-33 A, CaSki, and HT-3, and is localized in both the cell nucleus and cytoplasm. ZNF281 overexpression did not influence HeLa cell proliferation or tumor size in situ. Moreover, nude mice injected with ZNF281-overexpressing cell lines developed more tumor lesions in the lungs compared to those injected with control cell lines. Conclusions: These findings suggest that ZNF281 is associated with tumor metastasis without affecting cell proliferation, both in vivo and in vitro.

SNAI2 enhances HPV‑negative cervical cancer cell dormancy by modulating u‑PAR expression and the activity of the ERK/p38 signaling pathway in vitro

The prognosis of patients with human papillomavirus (HPV)‑negative cervical cancer is significantly worse than that of patients with HPV‑positive cervical cancer. Understanding the mechanisms of this is crucial for preventing disease evolution. In the present study, the GV367‑snail family transcriptional repressor 2 (SNAI2) lentiviral vector was constructed and transduced into C‑33A cells. Subsequently, the proliferation of tumor cells was detected using the Cell Counting Kit (CCK)‑8 method. Flow cytometry was used to analyze the cell cycle progression of tumor cells. The glucose consumption of tumor cells was detected using an oxidase assay, and the senescence of tumor cells was detected using beta‑galactosidase staining. The gene expression and the activity of p38 and ERK1/2 were detected using reverse transcription‑quantitative PCR and western blotting, respectively. The C‑33A‑SNAI2 cell line was successfully established. Compared with HeLa and C‑33A‑Wild cells, the proliferation and percentage of G0/G1‑phase cells in the C‑33A‑SNAI2 group were decreased, as detected by the CCK‑8 assay (100±0 vs. 239.1±58.3 vs. 39.7±20.1, P<0.01) and flow cytometry (34.0±7.1% vs. 46.2±10.6% vs. 61.3±5.3%, P<0.05). Compared with the HeLa group, the glucose consumption of the C‑33A‑Wild and C‑33A‑SNAI2 groups was significantly decreased (P<0.01). The results of beta‑galactosidase staining showed that the proportion of beta‑galactosidase‑positive cells in the C‑33A‑SNAI2 group was significantly decreased compared with the C‑33A‑Wild group (P<0.01). Upregulation of SNAI2 enhanced the increase in p21 expression, and the decrease in CDK1, urokinase plasminogen activator receptor (u‑PAR) and cyclin D1 expression in C‑33A cells compared with C‑33A‑Wild cells (P<0.05). In addition, the activities of p38, ERK1/2 and the phosphorylated (p)‑ERK1/2/p‑p38 ratio were decreased in the C‑33A‑SNAI2 group compared with the C‑33A‑Wild and HeLa groups (P<0.05). In conclusion, SNAI2 enhanced HPV‑negative cervical cancer C‑33A cell dormancy, which was characterized by G0/G1 arrest, by the downregulation of u‑PAR expression, and a decrease in the activity of the p‑ERK1/2 and p‑p38MAPK signaling pathways in vitro. Cancer recurrence and metastases are responsible for most cancer‑related deaths. Given that SNAI2 is required for enhancing HPV‑negative cervical cancer cell dormancy, regulating this process may promote cervical tumor cells to enter a continuous dormant state, which could be a potential approach for tumor therapy.

Tmprss2 maintains epithelial barrier integrity and transepithelial sodium transport

The mouse cortical collecting duct cell line presents a tight epithelium with regulated ion and water transport. The epithelial sodium channel (ENaC) is localized in the apical membrane and constitutes the rate-limiting step for sodium entry, thereby enabling transepithelial transport of sodium ions. The membrane-bound serine protease Tmprss2 is co-expressed with the alpha subunit of ENaC. αENaC gene expression followed the Tmprss2 expression, and the absence of Tmprss2 resulted not only in down-regulation of αENaC gene and protein expression but also in abolished transepithelial sodium transport. In addition, RNA-sequencing analyses unveiled drastic down-regulation of the membrane-bound protease CAP3/St14, the epithelial adhesion molecule EpCAM, and the tight junction proteins claudin-7 and claudin-3 as also confirmed by immunohistochemistry. In summary, our data clearly demonstrate a dual role of Tmprss2 in maintaining not only ENaC-mediated transepithelial but also EpCAM/claudin-7-mediated paracellular barrier; the tight epithelium of the mouse renal mCCD cells becomes leaky. Our working model proposes that Tmprss2 acts via CAP3/St14 on EpCAM/claudin-7 tight junction complexes and through regulating transcription of αENaC on ENaC-mediated sodium transport.

The Immunohistochemical Expression of Epithelial-Mesenchymal Transition Markers in Precancerous Lesions and Cervical Cancer

In the epithelial-mesenchymal transition (EMT) process, cells lose their epithelial phenotype and gain mesenchymal features. This phenomenon was observed in the metastatic phase of neoplastic diseases, e.g., cervical cancer. There are specific markers that are expressed in the EMT. The aim of this study was to determine the localization of and associations between the immunohistochemical (IHC) expression of TWIST, SNAIL, and SLUG proteins in precancerous lesions and cervical cancer. The IHC analysis disclosed higher expressions of EMT markers in precancerous lesions and cervical cancer than in the control group. Moreover, stronger expression of TWIST, SNAIL, and SLUG was observed in cervical intraepithelial neoplasia grade 3 (CIN3) vs. CIN1, CIN3 vs. CIN2, and CIN2 vs. CIN1 cases (p < 0.05). In cervical cancer, IHC reactions demonstrated differences in TWIST, SNAIL, and SLUG expression in grade 1 (G1) vs. grade 2 (G2) (p < 0.0011; p < 0.0017; p < 0.0001, respectively) and in G1 vs. grade 3 (G3) (p < 0.0029; p < 0.0005; p < 0.0001, respectively). The results of our study clearly showed that existing differences in the expression of the tested markers in precancerous vs. cancerous lesions may be utilized in the diagnosis of cervical cancer. Further studies on bigger populations, as well as in comparison with well-known markers, may improve our outcomes.

SNAI2 Attenuated the Stem-like Phenotype by Reducing the Expansion of EPCAMhigh Cells in Cervical Cancer Cells

SNAI2 (Snai2) is a zinc-finger transcriptional repressor that belongs to the Snail family. The accumulated evidence suggests that SNAI2 exhibits biphasic effects on regulating a stem-like phenotype in various types of cells, both normal and malignant. In this study, by exogenously expressing SNAI2 in SiHa cells, SNAI2 exhibited the capacity to inhibit a stem-like phenotype in cervical cancer cells. The SNAI2-overexpressing cells inhibited cell growth, tumorsphere formation, tumor growth, enhanced sensitivity to cisplatin, reduced stem cell-related factors' expression, and lowered tumor initiating frequency. In addition, the EPCAM^high cells sorted from SiHa cells exhibited an enhanced capacity to maintain a stem-like phenotype. Further study demonstrated that the trans-suppression of EPCAM expression by SNAI2 led to blockage of the nuclear translocation of β-catenin, as well as reduction in SOX2 and c-Myc expression in SiHa and HeLa cells, but induction in SNAI2 knockdown cells (CaSki), which would be responsible for the attenuation of the stem-like phenotype in cervical cancer cells mediated by SNAI2. All of these results demonstrated that SNAI2 could attenuate the stem-like phenotype in cervical cancer cells through the EPCAM/β-catenin axis.

Hexokinase 2 promoted cell motility and proliferation by activating Akt1/p-Akt1 in human ovarian cancer cells

Background

Recently, increasing evidence has indicated that elevation of Hexokinase 2 (HK2) plays an important role in several cancers on regulating cell motility and growth. However, its role on regulating cell EMT in human ovarian cancer still less to known.

Methods

The transwell and wound-healing assay were used to detect the effective of HK2 on regulating motility of ovarian cancer cells. Real Time PCR and Western Blotting were used to explore the changing of EMT-related proteins in HK2-modified cells. The clonogenic formation, cell growth curves and MTT assays were used to evaluate the effective of HK2 on regulating cell proliferation in HK2-modified cells. The flow cytometry was used to detect the differences in the distribution of cells in the cell cycle between the HK2-modified cells and their control cells. The correlation of HK2 and Akt1/p-Akt1 was explored by using Western Blotting, Akt1 inhibitor (MK2206) and transient transfection of an Akt1 recombinant plasmid. The potential correlation between HK2 and EMT-related proteins in human ovarian cancer tissues and OV (ovarian serous cystadenocarcinoma) was confirmed by using Pearson correlation analysis and TIMER 2.0.

Results

In ovarian cancer cells, overexpressing of HK2 enhanced cell motility by inducing of EMT-related proteins, such as CDH2, fibronectin, MMP9, ZEB1, ZEB2 and vimentin. Moreover, overexpressing of HK2 promoted cell growth by reducing p21 and p27 expression in ovarian cancer cells. Further studies demonstrated that this promotion of cell motility and growth by HK2 was probably a result of it activating of Akt1 (p-Akt1) in ovarian cancer cells. Additionally, the positive correlation between HK2 and p-Akt1, fibronectin, MMP9 expression in human ovarian cancer samples was verified by using Pearson correlation analysis. The positive correlation between HK2 and CDH2, fibronectin, MMP9, ZEB1, ZEB2 and vimentin in OV (ovarian serous cystadenocarcinoma) was confirmed by using TIMER 2.0.

Conclusion

This study demonstrated that HK2 could induce EMT-related proteins and reduce cell cycle inhibitor by activating Akt1 in human ovarian cancer cells, subsequently enhancing cell motility and growth, suggesting that HK2 participate in the malignant process of ovarian cancer by interacting with Akt1.

Hexokinases 2 promoted cell motility and distant metastasis by elevating fibronectin through Akt1/p-Akt1 in cervical cancer cells

Background

Hexokinases 2 (HK2) is a member of the hexokinases, linking with malignant tumor growth and distant metastasis. However, evidence regarding the potential role of HK2 in regulating cell motility and tumor metastasis during the cervical cancer malignant progression remains limited.

Methods

In vitro migration and invasion assay, in vivo metastasis experiments were performed to detect the effective of HK2 on regulating cell motility and tumor metastasis in cervical cancer cells. RNA-Seq was performed to explore the potential molecules that participate in HK2-mediated cell motility and tumor metastasis in cervical cancer cells. The correlation between HK2 and Akt1, p-Akt1, FN1 expression in cervical cancer cells and human squamous cervical carcinoma (SCC) samples was verified in this study.

Results

In this study, cervical cancer cells with exogenous HK2 expression exhibited enhanced cell motility and distant metastasis. Transcriptome sequencing analysis revealed that fibronectin (FN1) was significantly increased in HK2-overexpressing HeLa cells, and the PI3K/Akt signaling pathway was identified by KEGG pathway enrichment analysis. Further studies demonstrated that this promotion of cell motility by HK2 was probably a result of it inducing FN1, MMP2 and MMP9 expression by activating Akt1 in cervical cancer cells. Additionally, HK2 expression was altered with the changing of Akt1/p-Akt1 expression, implying that HK2 expression is also modulated by Akt1/p-Akt1. Moreover, the positive correlation between HK2 and Akt1, p-Akt1, FN1 expression in human squamous cervical carcinoma (SCC) samples was verified by using Pearson correlation analysis.

Conclusions

This study demonstrated that HK2 could activate Akt1 in cervical cancer cells, subsequently enhancing cell motility and tumor metastasis by inducing FN1, MMP2 and MMP9 expression. There likely exists an interactive regulatory mechanism between HK2 and Akt1 during the malignant process of cervical cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02312-0.