TGF-β1 pathway affects the protein expression of many signaling pathways, markers of liver cancer stem cells, cytokeratins, and TERT in liver cancer HepG2 cells

Celastrus orbiculatus extract suppresses gastric cancer stem cells through the TGF-β/Smad signaling pathway

Cancer stem cells (CSCs) are the primary source of tumor recurrence and chemoresistance, which complicates tumor treatment and has a significant impact on poor patient prognosis. Therefore, the discovery of inhibitors that specifically target CSCs is warranted. Previous research has established that the TGF-β/Smad signaling pathway is critical for the maintenance of CSCs phenotype, thus facilitating CSCs transformation. In this regard, Celastrus orbiculatus ethyl acetate extract (COE) was shown to exert anticancer properties; however, its therapeutic impact on gastric cancer stem cells (GCSCs) remains unknown. We here demonstrate that COE displayed a strong inhibitory effect on GCSCs growth and CSCs markers. Moreover, COE was shown to efficiently inhibit the development of tumor spheres and accelerate GCSCs apoptosis. Mechanistically, we established that COE could suppress the stemness phenotype of GCSCs by inhibiting the activity of the TGF-β/Smad signaling pathway. To summarize, our data indicate that COE suppresses the malignant biological phenotype of GCSCs via the TGF-β/Smad signaling pathway. These findings shed new light on the anticancer properties of COE and suggest new strategies for the development of efficient GCSCs therapeutics.

Exploring the dynamic interplay between cancer stem cells and the tumor microenvironment: implications for novel therapeutic strategies

Cancer stem cells (CSCs) have emerged as key contributors to tumor initiation, growth, and metastasis. In addition, CSCs play a significant role in inducing immune evasion, thereby compromising the effectiveness of cancer treatments. The reciprocal communication between CSCs and the tumor microenvironment (TME) is observed, with the TME providing a supportive niche for CSC survival and self-renewal, while CSCs, in turn, influence the polarization and persistence of the TME, promoting an immunosuppressive state. Consequently, these interactions hinder the efficacy of current cancer therapies, necessitating the exploration of novel therapeutic approaches to modulate the TME and target CSCs. In this review, we highlight the intricate strategies employed by CSCs to evade immune surveillance and develop resistance to therapies. Furthermore, we examine the dynamic interplay between CSCs and the TME, shedding light on how this interaction impacts cancer progression. Moreover, we provide an overview of advanced therapeutic strategies that specifically target CSCs and the TME, which hold promise for future clinical and translational studies in cancer treatment.

Cell signaling pathways as molecular targets to eliminate AML stem cells

Acute myeloid leukemia (AML) remains the most lethal of leukemias and a small population of cells called leukemic stem cells (LSCs) has been associated with disease relapses. Some cell signaling pathways play an important role in AML survival, proliferation and self-renewal properties and are abnormally activated or suppressed in LSCs. This includes the NF-κB, Wnt/β-catenin, Hedgehog, Notch, EGFR, JAK/STAT, PI3K/AKT/mTOR, TGF/SMAD and PPAR pathways. This review aimed to discuss these pathways as molecular targets for eliminating AML LSCs. Herein, inhibitors/activators of these pathways were summarized as a potential new anti-AML therapy capable of eliminating LSCs to guide future researches. The clinical use of cell signaling pathways data can be useful to enhance the anti-AML therapy.

Tumor-cell detection, labeling and phenotyping with an electron-doped bifunctional signal-amplifier

Cancer cell enumeration and phenotyping can predict the prognosis and the therapy efficacy in patients, yet it remains challenging to detect the rare tumor cells. Herein, we report an octopus-inspired, bifunctional aptamer signal amplifier-based cytosensor (OApt-cytosensor) for sensitive cell analysis. By assembling high-affinity antibodies on an electrode surface, the target cells could be specifically captured and thus been sandwiched by the cell surface marker-specific DNA aptamers. These on-cell aptamers function as electrochemical signal amplifiers by base-selective electronic doping with methylene blue. Such a sandwich configuration enables highly sensitive cell detection down to 10 cells/mL (equal to ~1-2 cells at a sampling volume of 150 μL), even in a large excess of nontarget blood cells. This approach also reveals the cell-surface markers and tracks the cellular epithelial-to-mesenchymal transition induced by signaling regulators. Furthermore, the electron-doped aptamer shows remarkable cell fluorescent labeling that guides the release of the captured cells from electrode surface via electrochemistry. These features make OApt-cytosensor a promising tool in revealing the heterogeneous cancer cells and anticancer drug screening at the single-cell level.

Targeting cancer stem cell pathways for cancer therapy

Since cancer stem cells (CSCs) were first identified in leukemia in 1994, they have been considered promising therapeutic targets for cancer therapy. These cells have self-renewal capacity and differentiation potential and contribute to multiple tumor malignancies, such as recurrence, metastasis, heterogeneity, multidrug resistance, and radiation resistance. The biological activities of CSCs are regulated by several pluripotent transcription factors, such as OCT4, Sox2, Nanog, KLF4, and MYC. In addition, many intracellular signaling pathways, such as Wnt, NF-κB (nuclear factor-κB), Notch, Hedgehog, JAK-STAT (Janus kinase/signal transducers and activators of transcription), PI3K/AKT/mTOR (phosphoinositide 3-kinase/AKT/mammalian target of rapamycin), TGF (transforming growth factor)/SMAD, and PPAR (peroxisome proliferator-activated receptor), as well as extracellular factors, such as vascular niches, hypoxia, tumor-associated macrophages, cancer-associated fibroblasts, cancer-associated mesenchymal stem cells, extracellular matrix, and exosomes, have been shown to be very important regulators of CSCs. Molecules, vaccines, antibodies, and CAR-T (chimeric antigen receptor T cell) cells have been developed to specifically target CSCs, and some of these factors are already undergoing clinical trials. This review summarizes the characterization and identification of CSCs, depicts major factors and pathways that regulate CSC development, and discusses potential targeted therapy for CSCs.

Hypoxia‑inducible factors in hepatocellular carcinoma (Review)

Maintenance of an appropriate oxygen concentration is essential for the function of the liver. However, in many pathological conditions, and particularly in the tumor microenvironment, cells and tissues are frequently in a hypoxic state. In the presence of hypoxia, the cells adapt to the low oxygen levels through the hypoxia-inducible factor (HIF) pathway. Overgrowth of tumor cells restricts the diffusion of oxygen in tumors, leading to insufficient blood supply and the creation of a hypoxic microenvironment, and, as a consequence, activation of the expression of HIFs. HIFs possess a wide range of target genes, which function to control a variety of signaling pathways; thus, HIFs modulate cellular metabolism, immune escape, angiogenesis, metastasis, extracellular matrix remodeling, cancer stem cells and other properties of the tumor. Given their crucial role in the occurrence and development of tumors, HIFs are expected to become new targets of precise treatment of hepatocellular carcinoma.

The miR-590/Acvr2a/Terf1 Axis Regulates Telomere Elongation and Pluripotency of Mouse iPSCs

During reprogramming, telomere re-elongation is important for pluripotency acquisition and ensures the high quality of induced pluripotent stem cells (iPSCs), but the regulatory mechanism remains largely unknown. Our study showed that fully reprogrammed mature iPSCs or mouse embryonic stem cells expressed higher levels of miR-590-3p and miR-590-5p than pre-iPSCs. Ectopic expression of either miR-590-3p or miR-590-5p in pre-iPSCs improved telomere elongation and pluripotency. Activin receptor II A (Acvr2a) is the downstream target and mediates the function of miR-590. Downregulation of Acvr2a promoted telomere elongation and pluripotency. Overexpression of miR-590 or inhibition of ACTIVIN signaling increased telomeric repeat binding factor 1 (Terf1) expression. The p-SMAD2 showed increased binding to the Terf1 promoter in pre-iPSCs compared with mature iPSCs. Downregulation of Terf1 blocked miR-590- or shAcvr2a-mediated promotion of telomere elongation and pluripotency in pre-iPSCs. This study elucidated the role of the miR-590/Acvr2a/Terf1 signaling pathway in modulating telomere elongation and pluripotency in pre-iPSCs.

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miR-590 is critical for telomere elongation and pluripotency of pre-iPSCs

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miR-590 can target Acvr2a to upregulate the expression of Terf1

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miR-590/Acvr2a/Terf1 axis regulates the elongation and pluripotency of pre-iPSCs

TERT expression in gastric carcinogenesis: Correlation with clinical features

AIM

To investigate the expression of telomerase reverse transcriptase (TERT) mRNA in gastric cancer and precancerous lesions, and to analyze the relationship between TERT expression and clinicopathologic features and prognosis in gastric cancer.

METHODS

From September 2011 to October 2016, 102 patients with gastric cancer, 32 patients with precancerous lesions, and 30 patients with chronic non-atrophic gastritis were treated at the First Affiliated Hospital of Jiamus University. The expression of TERT mRNA in tissues was detected by real-time quantitative PCR, and the correlation of expression of TERT with clinicopathologic features and prognosis in gastric cancer was analyzed.

RESULTS

The expression of TERT in gastric cancer and precancerous lesions was significantly higher than that in chronic non-atrophic gastritis (P < 0.05). TERT expression was significantly correlated with the depth of invasion, TNM stage, vascular invasion, and lymph node metastasis (P < 0.05). The overall survival rate of gastric cancer patients with high expression of TERT was significantly lower than that of patients with low expression of TERT (HR = 0.420, 95%CI: 0.264-0.668, P < 0.001). The progression-free survival rate of gastric cancer patients with high expression of TERT was also significantly lower than that of patients with low TERT expression (HR = 0.649, 95%CI: 0.421-0.999, P = 0.049). Cox multivariate survival analysis showed that TERT expression was an independent prognostic factor for overall survival in gastric cancer.

CONCLUSION

TERT is highly expressed in gastric cancer and precancerous lesions, and high expression of TERT is significantly associated with the clinicopathologic features and prognosis of gastric cancer patients.

FAM83D associates with high tumor recurrence after liver transplantation involving expansion of CD44+ carcinoma stem cells

To investigate the potential oncogene promoting recurrence of hepatocellular carcinoma (HCC) following liver transplantation (LT), throughput RNA sequencing was performed in a subgroup of HCC patients. The up-regulated FAM83D in HCC tissues was found and further verified in 150 patients by real-time PCR and immunohistochemistry. FAM83D overexpression significantly correlated with high HCC recurrence rate following LT and poor HCC characteristics such as high AFP, poor differentiation. Of cancer stem cells (CSCs) markers, CD44 expression was effectively suppressed when FAM83D was knocked down by siRNA. Meanwhile, the siRNA transfected cells suppressed formation of sphere and ability of self-renew. In a xenograft tumorigenesis model, FAM83D knockdown apparently inhibited tumor growth and metastasis. Microarray assays revealed that FAM83D promotes CD44 expression via activating the MAPK, TGF-β and Hippo signaling pathways. Furthermore, CD44 knockdown presented reverse effect on above signaling pathways, which suggested that FAM83D was a key activator of loop between CD44 and above signaling pathways. In conclusion, FAM83D promotes HCC recurrence by promoting CD44 expression and CD44⁺ CSCs malignancy. FAM83D provides a novel therapeutic approach against HCC recurrence after LT.

miR‑196a‑5p modulates gastric cancer stem cell characteristics by targeting Smad4

Cancer stem cells (CSCs) are undifferentiated cancer cells with a high tumorigenic activity, the ability to undergo self-renewal, and a multilineage differentiation potential. Clinical evidence suggests that CSCs in a tumor mass are the cellular determinants to promote cancer invasion and metastasis. MicroRNAs (miRNAs) have emerged as important modulators of cancer stem cell characteristics. Unveiling the candidate miRNAs that regulate CSCs may provide novel therapeutic targets against cancer. We analyzed the miRNA expression profiles regulating the cancer stem-like cell characteristics in gastric cancer. Gastric cancer stem cells (GCSCs) were sorted using the stem cell marker CD44 by fluorescence-activated cell sorting. Functional studies revealed that CD44(+) cells formed more sphere colonies and showed higher invasiveness than CD44(−) cells. miRNA microarray analysis revealed that miR-196a-5p was significantly upregulated in CD44(+) cells than CD44(−) cells. Suppression of miR-196a-5p led to decreased colony formation and invasion of GCSCs. miR-196a-5p decreased the expression of Smad4 by targeting 3′-UTR of the mRNA. The expression of Smad4 in gastric cancer tissues was correlated with differentiation state of tumors, TNM stage and depth of invasion. The stimulation of epithelial-mesenchymal transition (EMT) by miR-196a-5p in cancer stem-like cells was abolished by overexpression of Smad4. Collectively, these data demonstrate that miR-196a-5p has a key role in EMT and invasion by targeting Smad4 in GCSCs. miR-196a-5p may serve as a potential target for gastric cancer therapy.

CD109 Mediates Cell Survival in Hepatocellular Carcinoma Cells

BACKGROUND

Hepatocellular carcinoma (HCC) accounts for 75-80 % of primary liver cancer, and usually arises after years of liver disease. Thus it is important to understand the molecular mechanisms which drive or mediate the development of HCC.

AIM

In this work, we examined whether CD109 was associated with a poor prognosis in HCC and explored possible underlying mechanisms.

METHODS

We examined the CD109 and Ki67 expression levels in 97 patients with HCC using immunohistochemistry. CD109 levels in HCC cells were down-regulated by shRNA transfection. The cycle progression and cell proliferation status of HCC cells were evaluated by flow cytometry and CCK-8 assay. The effect of CD109 on proliferation and apoptosis was investigated by western blot and TUNEL activity assays.

RESULTS

The CD109 protein was up-regulated in HCC tissue compared with adjacent noncancerous tissue. CD109 expression levels in the 97 patients with HCC were positively correlated with histological grade. Univariate and multivariate survival analysis revealed that CD109 was a significant predictor of overall survival among HCC patients. CD109 shRNA knockdown delayed the G1-S phase transition, abrogated cell proliferation, and increased cell apoptosis. Furthermore, CD109 impaired TGF-β/Smad signaling through control of p-smad2.

CONCLUSIONS

CD109 promoted HCC proliferation and predicted poor prognosis. In addition, CD109 expression was associated with anti-apoptosis in HCC cells.

Expression Profile and Function Analysis of LncRNAs during Priming Phase of Rat Liver Regeneration

Emerging evidences have revealed that long non-coding RNAs (lncRNAs) functioned in a wide range of physiological and pathophysiological processes including rat liver regeneration, and could regulate gene expression in the transcriptional and post-transcriptional levels. However, the underlying mechanism for lncRNAs participation in liver regeneration is largely unknown. To define the mechanisms how the lncRNAs regulate LR, we performed bio-chip technology, high-throughput sequencing and RT-PCR to detect the expression of lncRNAs at 0, 2 and 6 h during LR after 2/3 hepatectomy (PH). The results indicated that 28 lncRNAs were involved in LR. Bioinformatics analysis predicated 465 co-expression target genes including 10 regulatory genes were related to these 28 lncRNAs. Ingenuity Pathway Analysis (IPA) was employed to analyze the signaling pathways and physiological activities that regulated by these genes, and the results suggested that these genes were potentially related to ILK, SAPK/JNK and ERK/MAPK signaling pathways, and possibly regulate many important physiological activities in LR in terms of cell proliferation, cell differentiation, cell survival, apoptosis and necrosis.