ERK1/2 promoted proliferation and inhibited apoptosis of human cervical cancer cells and regulated the expression of c-Fos and c-Jun proteins

A literature review on signaling pathways of cervical cancer cell death-apoptosis induced by Traditional Chinese Medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Cervical cancer (CC) is a potentially lethal disorder that can have serious consequences for a woman's health. Because early symptoms are typically only present in the middle to late stages of the disease, clinical diagnosis and treatment can be challenging. Traditional Chinese medicine (TCM) has been shown to have unique benefits in terms of alleviating cancer clinical symptoms, lowering the risk of recurrence after surgery, and reducing toxic side effects and medication resistance after radiation therapy. It has also been shown to improve the quality of life for patients. Because of its improved anti-tumor effectiveness and biosafety, it could be considered an alternative therapy option. This study examines how TCM causes apoptosis in CC cells via signal transduction, including the active components and medicinal tonics. It also intends to provide a reliable clinical basis and protocol selection for the TCM therapy of CC.

METHODS

The following search terms were employed in PubMed, Web of Science, Embase, CNKI, Wanfang, VIP, SinoMed, and other scientific databases to retrieve pertinent literature on "cervical cancer," "apoptosis," "signaling pathway," "traditional Chinese medicine," "herbal monomers," "herbal components," "herbal extracts," and "herbal formulas."

RESULTS

It has been demonstrated that herbal medicines can induce apoptosis in cells of the cervix, a type of cancer, by influencing the signaling pathways involved.

CONCLUSION

A comprehensive literature search was conducted, and 148 papers from the period between January 2017 and December 2023 were identified as eligible for inclusion. After a meticulous process of screening, elimination and summary, generalization, and analysis, it was found that TCM can regulate multiple intracellular signaling pathways and related molecular targets, such as STAT3, PI3K/AKT, Wnt/β-catenin, MAPK, NF-κB, p53, HIF-1α, Fas/FasL and so forth. This regulatory capacity was observed to induce apoptosis in cervical cancer cells. The study of the mechanism of TCM against cervical cancer and the screening of new drug targets is of great significance for future research in this field. The results of this study will provide ideas and references for the future development of Chinese medicine in the diagnosis and treatment of cervical cancer.

Exploring MiR-484 Regulation by Polyalthia longifolia: A Promising Biomarker and Therapeutic Target in Cervical Cancer through Integrated Bioinformatics and an In Vitro Analysis

BACKGROUND

MiR-484, implicated in various carcinomas, holds promise as a prognostic marker, yet its relevance to cervical cancer (CC) remains unclear. Our prior study demonstrated the Polyalthia longifolia downregulation of miR-484, inhibiting HeLa cells. This study investigates miR-484's potential as a biomarker and therapeutic target in CC through integrated bioinformatics and an in vitro analysis.

METHODS

MiR-484 levels were analyzed across cancers, including CC, from The Cancer Genome Atlas. The limma R package identified differentially expressed genes (DEGs) between high- and low-miR-484 CC cohorts. We assessed biological functions, tumor microenvironment (TME), immunotherapy, stemness, hypoxia, RNA methylation, and chemosensitivity differences. Prognostic genes relevant to miR-484 were identified through Cox regression and Kaplan-Meier analyses, and a prognostic model was captured via multivariate Cox regression. Single-cell RNA sequencing determined cell populations related to prognostic genes. qRT-PCR validated key genes, and the miR-484 effect on CC proliferation was assessed via an MTT assay.

RESULTS

MiR-484 was upregulated in most tumors, including CC, with DEGs enriched in skin development, PI3K signaling, and immune processes. High miR-484 expression correlated with specific immune cell infiltration, hypoxia, and drug sensitivity. Prognostic genes identified were predominantly epidermal and stratified patients with CC into risk groups, with the low-risk group showing enhanced survival and immunotherapeutic responses. qRT-PCR confirmed FGFR3 upregulation in CC cells, and an miR-484 mimic reversed the P. longifolia inhibitory effect on HeLa proliferation.

CONCLUSION

MiR-484 plays a crucial role in the CC progression and prognosis, suggesting its potential as a biomarker for targeted therapy.

miR-129-5p inhibits anchorage-independent growth through silencing of ACTN1 and the ELK4/c-FOS axis in HPV-transformed keratinocytes

A persistent infection with human papillomavirus (HPV) can induce precancerous lesions of the cervix that may ultimately develop into cancer. Cervical cancer development has been linked to altered microRNA (miRNA) expression, with miRNAs regulating anchorage-independent growth being particularly important for the progression of precancerous lesions to cancer. In this study, we set out to identify and validate targets of miR-129-5p, a previously identified tumor suppressive miRNA involved in anchorage-independent growth and HPV-induced carcinogenesis. We predicted 26 potential miR-129-5p targets using online databases, followed by KEGG pathway enrichment analysis. RT-qPCR and luciferase assays confirmed that 3'UTR regions of six genes (ACTN1, BMPR2, CAMK4, ELK4, EP300, and GNAQ) were targeted by miR-129-5p. Expressions of ACTN1, CAMK4, and ELK4 were inversely correlated to miR-129-5p expression in HPV-transformed keratinocytes, and their silencing reduced anchorage-independent growth. Concordantly, miR-129-5p overexpression decreased protein levels of ACTN1, BMPR2, CAMK4 and ELK4 in anchorage-independent conditions. Additionally, c-FOS, a downstream target of ELK4, was downregulated upon miR-129-5p overexpression, suggesting regulation through the ELK4/c-FOS axis. ACTN1 and ELK4 expression was also upregulated in high-grade precancerous lesions and cervical cancers, supporting their clinical relevance. In conclusion, we identified six targets of miR-129-5p involved in the regulation of anchorage-independent growth, with ACTN1, BMPR2, ELK4, EP300, and GNAQ representing novel targets for miR-129-5p. For both ACTN1 and ELK4 functional and clinical relevance was confirmed, indicating that miR-129-5p-regulated ACTN1 and ELK4 expression contributes to HPV-induced carcinogenesis.

PHF5A facilitates the development and progression of gastric cancer through SKP2-mediated stabilization of FOS

BACKGROUND

Gastric cancer (GC) is the fifth most common cancer and the third most common cause of cancer death worldwide. Plant homeodomain (PHD)-finger domain protein PHF5A has been demonstrated to play a promoting role in a variety of cancers. This study aimed to clarify the role of PHF5A in the progression of GC and its potential mechanism of action.

METHODS

Immunohistochemical staining experiments were performed based on tissues from clinical GC patients to reveal PHF5A expression. A series of functional experiments in vitro and in vivo were used to clarify the role of PHF5A in GC.

RESULTS

Clinically, PHF5A was abundantly expressed in GC and existed clinical value indicating poor prognosis. In addition, GC cells with knockdown of PHF5A expression showed slowed proliferation, enhanced sensitivity to apoptosis and inhibition of migration. Mechanically, knockdown of PHF5A led to decreased protein stability of FOS, which was mediated ubiquitination of E3 ubiquitin ligase S-phase kinase-associated protein 2 (SKP2). Moreover, downregulation of FOS attenuated the promotion of PHF5A overexpression on GC cells. Consistently, Pladienolide B (PHF5A inhibitor) treatment reversed the induction of PHF5A overexpression on the malignant phenotypes and tumor formation of GC cells.

CONCLUSION

Knockdown of PHF5A inhibited the progression of GC through SKP2-mediated ubiquitination of FOS, which may be a promising candidate target with potential therapeutic value.

The FnBPA from methicillin-resistant Staphylococcus aureus promoted development of oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is the most common tumor in the oral cavity. Methicillin-resistant Staphylococcus aureus (MRSA) were highly detected in OSCC patients; however, the interactions and mechanisms between drug-resistant bacteria (MRSA) and OSCC are not clear.

Aim

The aim of this study was to investigate the promotion of MRSA on the development of OSCC.

Methods

MRSA and MSSA (methicillin-susceptible) strains were employed to investigate the effect on the proliferation of OSCC in vitro and vivo.

Results

All of the MRSA strains significantly increased the proliferation of OSCC cells and MRSA arrested the cell cycles of OSCC cells in the S phase. MRSA activated the expression of TLR-4, NF-κB and c-fos in OSCC cells. MRSA also promoted the development of squamous cell carcinoma in vivo. The virulence factor fnbpA gene was significantly upregulated in all MRSA strains. By neutralizing FnBPA, the promotions of MRSA on OSCC cell proliferation and development of squamous cell carcinoma were significantly decreased. Meanwhile, the activation of c-fos and NF-κB by MRSA was also significantly decreased by FnBPA antibody.

Conclusion

MRSA promoted development of OSCC, and the FnBPA protein was the critical virulence factor. Targeting virulence factors is a new method to block the interaction between a drug-resistant pathogen and development of tumors.

Exploring the mechanism and experimental verification of puerarin in the treatment of endometrial carcinoma based on network pharmacology and bioinformatics analysis

Endometrial carcinoma is one of the two cancers with rising mortality and morbidity in recent years. In the light of many controversies about its treatment, it is urgent to construct a new prognostic model and to find out new therapeutic directions. As a small drug molecule widely used in clinical treatment and experimental research in China, puerarin has recently been proven to have obvious anti-cancer effects in multiple cancer cells. In this study, bioinformatics analysis and experimental validation were used to explore the potential mechanism of puerarin for endometrial carcinoma and construct a prognostic model. A total of 22 drug-related differential genes were found by constructing a database of drug targets and disease genes. The protein–protein interaction network was constructed for GO and KEGG enrichment analysis to initially explore the potential mechanism of its therapeutic effects. To construct the prognostic model, validation was performed by risk regression analysis and LASSO analysis. Finally, two prognostic genes—PIM1 and BIRC5 were determined to establish high and low risk groups. Kaplan–Meier analysis displayed a higher survival rate in the low-risk group than in the high-risk group. ROC curves indicated the stable and good effect in prediction (one-year AUC is 0.626; two-year AUC is 0.620; three-year AUC is 0.623). The interrelationship between immunity and its disease was explored by immune infiltration analysis. Finally, the potential effect of puerarin on endometrial carcinoma cells was further verified by experiments.

Glycosphingolipids are mediators of cancer plasticity through independent signaling pathways

The molecular repertoire promoting cancer cell plasticity is not fully elucidated. Here, we propose that glycosphingolipids (GSLs), specifically the globo and ganglio series, correlate and promote the transition between epithelial and mesenchymal cells. The epithelial character of ovarian cancer remains stable throughout disease progression, and spatial glycosphingolipidomics reveals elevated globosides in the tumor compartment compared with the ganglioside-rich stroma. CRISPR-Cas9 knockin mediated truncation of endogenous E-cadherin induces epithelial-to-mesenchymal transition (EMT) and decreases globosides. The transcriptomics analysis identifies the ganglioside-synthesizing enzyme ST8SIA1 to be consistently elevated in mesenchymal-like samples, predicting poor outcome. Subsequent deletion of ST8SIA1 induces epithelial cell features through mTOR^S2448 phosphorylation, whereas loss of globosides in ΔA4GALT cells, resulting in EMT, is accompanied by increased ERK^Y202/T204 and AKT^S124. The GSL composition dynamics corroborate cancer cell plasticity, and further evidence suggests that mesenchymal cells are maintained through ganglioside-dependent, calcium-mediated mechanisms.

Corema album Leaves Mediate DNA Damage in Triple-Negative Breast Cancer Cells

Corema (C.) album is a shrub endemic to the Atlantic coast and has been described as yielding beneficial effects for human health. Nevertheless, studies concerning the bioactivity of C. album leaves are scarce. This study aims at investigating the anticancer potential and mode of action, of an hydroethanolic extract of C. album leaves (ECAL) on triple-negative breast cancer. This is a poor survival breast cancer subtype, owing to its high risk of distant reappearance, metastasis rates and the probability of relapse. The ECAL ability to prevent tumor progression through (i) the inhibition of cell proliferation (cell viability); (ii) the induction of apoptosis (morphological changes, TUNEL assay, caspase-3 cleaved) and (iii) the induction of DNA damage (PARP1 and γH2AX) with (iv) the involvement of NF-κB and of ERK1/2 pathways (AlphaScreen assay) was evaluated. ECAL activated the apoptotic pathway (through caspase-3) along with the inhibition of ERK and NF-κB pathways causing DNA damage and cell death. The large polyphenolic content of ECAL was presumed to be accountable for these effects. The extract of C. album leaves can target multiple pathways and, thus, can block more than one possible means of disease progression, evidencing the anticancer therapeutic potential from a plant source.

Selenite induced breast cancer MCF7 cells apoptosis through endoplasmic reticulum stress and oxidative stress pathway

Selenium is an essential trace element for human, and has anti-tumor effects. In this study, we investigated the anti-tumor activity of sodium selenite (Na₂SeO₃) and explored its possible mechanisms involved in a breast cancer cell line. We found that Na₂SeO₃ could inhibit the cell viability of MCF7 cells, yet with minimal damage to human umbilical vein endothelial cells (HUVECs). The results of Hoechst staining and Western Blot showed that Na₂SeO₃ induced apoptosis of MCF7 cells. Na₂SeO₃ activated endoplasmic reticulum stress (ERS), as evidenced by the up-regulation of ERS-related proteins, including ATF6, p-eIF2α, ATF4, and CHOP, and the down-regulation of PERK. ATF6, p-eIF2α and apoptosis were decreased by pre-treatment with an ERS inhibitor (4-PBA). Na₂SeO₃ activated oxidative stress (OS) through increasing ROS generation and decreasing mitochondrial membrane potential (MMP) which induced apoptosis. Pre-treatment with an antioxidant (NAC) attenuated Na₂SeO₃-induced OS and cell apoptosis. Furthermore, ERS and OS had mutual effects. Pre-treatment with 4-PBA could act against the up-regulation of ROS and the down-regulation of MMP. Pre-treatment with NAC attenuated the expression of ATF6. At the same time, we found that treatment with Na₂SeO₃ promoted the phosphorylation of p38 and JNK, while inhibiting the phosphorylation of ERK. However, the up-regulation was inhibited after pre-treatment of NAC, and pre-treatment with 4-PBA inhibited the increase only of p38. Based on these results, our study provides a mechanistic understanding of how Na₂SeO₃ has antitumor effects against MCF7 cells through the OS and ERS pathway. OS and ERS interact with each other, and p38 is regulated by them.

Tissue-specific Physical and Biological Microenvironments Modulate the Behavior of Cervical Squamous Cell Carcinoma

The mechanisms controlling the aggressiveness and survival of cervical SCC cells remain unclear. We investigated how the physical and biological microenvironments regulate the growth, apoptosis and invasiveness of cervical cancer cells. Dynamic flow and air exposure were evaluated as physical microenvironmental factors, and stromal fibroblasts were evaluated as a biological microenvironmental factor. To investigate any regulatory effects of these microenvironmental factors, we established a new culture model which concurrently replicates fluid streaming, air exposure and cancer-stromal interactions. Three cervical cancer cell lines were cultured with or without NIH 3T3 fibroblasts. Air exposure was realized using a double-dish culture system. Dynamic flow was created using a rotary shaker. Dynamic flow and air exposure promoted the proliferative activity and decreased the apoptosis of cervical cancer cells. Fibroblasts regulated the invasive ability, growth and apoptosis of cervical cancer cells. Extracellular signal-regulated kinase and p38 signaling were regulated either synergistically or independently by dynamic flow, air exposure and cellular interactions, depending on the cervical cancer cell type. This study demonstrates that the physical and biological microenvironments interact to regulate the aggressiveness and survival of cervical cancer cells. Our simple culture system is a promising model for developing further treatment strategies for various types of cancer.

The inhibition of GHR enhanced cytotoxic effects of etoposide on neuroblastoma

Etoposide, a DNA damage-inducing agent, is widely used to treat neuroblastoma. Etoposide binds to and inhibits topoisomerase II, thereby inducing the DNA damage response. However, the underlying mechanism of etoposide resistance in neuroblastoma remains unclear. The results of the present study revealed that etoposide upregulated growth hormone receptor (GHR) expression levels in etoposide-resistant neuroblastoma cells, suggesting that GHR upregulation may be involved in the underlying mechanism of etoposide resistance. Thus, the combined effect of GHR knockdown and etoposide treatment on cell viability, apoptosis and migration in vitro, as well as tumor growth in mouse xenograft models in vivo, was subsequently analyzed. The results of cell viability and colony formation assays demonstrated that GHR knockdown enhanced the inhibitory effects of etoposide on cell viability and sensitized cells to etoposide. The enhanced cell viability was discovered to be, at least in part, due to the increase in etoposide-induced apoptosis following GHR knockdown. Moreover, the knockdown of GHR enhanced the inhibitory effect of etoposide on cell migration. Mouse xenograft studies confirmed the effects of GHR silencing in etoposide-resistant neuroblastoma progression in vivo. Furthermore, the effects of GHR knockdown in etoposide resistance were hypothesized to occur via the inactivation of the MEK/ERK signaling pathway. In conclusion, the results of the present study provided novel insight into the underlying mechanism of etoposide resistance and a potential target for the treatment of etoposide-resistant neuroblastoma.

Knockdown of RNF6 inhibits HeLa cervical cancer cell growth via suppression of MAPK/ERK signaling

Ring finger protein 6 (RNF6) is implicated in various human malignancies, but its function in cervical cancer (CC) is incompletely understood. Here, we explored the biological significance of RNF6 in HeLa CC cells and the underlying regulatory mechanisms. The expression of RNF6 was observed to be high in both primary tissues and CC cells. RNF6 promoted HeLa CC cell growth. Knockdown of RNF6 in CC cells resulted in suppression of proliferation and promotion of apoptosis. Moreover, elevation of RNF6 had an adverse effect on the prognosis of CC. Subsequent analyses showed that these effects may be mediated via activation of ERK signaling. These findings provide evidence that the knockdown of RNF6 suppresses the MAPK/ERK pathway to regulate the growth of CC cells, which suggests that RNF6 may have potential as a target for diagnosis and treatment for CC.

A Comprehensive Understanding of the Anticancer Mechanisms of FDY2004 Against Cervical Cancer Based on Network Pharmacology

Herbal drugs are continuously being developed and used as effective therapeutics for various cancers, such as cervical cancer (CC); however, their mechanisms of action at a systemic level have not been explored fully. To study such mechanisms, we conducted a network pharmacological investigation of the anti-CC mechanisms of FDY2004, an herbal drug consisting of Moutan Radicis Cortex, Persicae Semen , and Rhei Radix et Rhizoma. We found that FDY2004 inhibited the viability of human CC cells. By performing pharmacokinetic evaluation and network analysis of the phytochemical components of FDY2004, we identified 29 bioactive components and their 116 CC-associated pharmacological targets. Gene ontology enrichment analysis showed that the modulation of cellular functions, such as apoptosis, growth, proliferation, and survival, might be mediated through the FDY2004 targets. The therapeutic targets were also key components of CC-associated oncogenic and tumor-suppressive pathways, including PI3K-Akt, human papillomavirus infection, IL-17, MAPK, TNF, focal adhesion, and viral carcinogenesis pathways. In conclusion, our data present a comprehensive insight for the mechanisms of the anti-CC properties of FDY2004.

Knockdown of eIF3a attenuated cell growth in K1 human thyroid cancer cells

BACKGROUND

In ribosome establishment and the initiation of translation, eukaryotic translation initiation factor (eIF) 3a is a pivotal functional subunit of the eIF3 complex. In various cancer types, abnormal eIF3a expression plays an important role in tumorigenesis.

OBJECTIVE

We aimed to explore the role of eIF3a in human thyroid cancer (TC).

MATERIAL AND METHODS

The expression of eIF3a was determined in TC tissues by qRT-PCR and immunohistochemistry (IHC) assay, respectively. In addition, the expression of eIF3a in K1 and BCPAP cells were detected by qRT-PCR. Cell proliferation, cell cycle, and cell apoptosis were assessed after eIF3a knockdown in K1 in cell line.

RESULTS

The expression of eIF3a mRNA was high in TC tissues and cancer cell lines. Moreover, eIF3a expression in TC tissues indicated that high eIF3a level was associated with tumor grade. In addition, eIF3a knockdown resulted in a significantly decrease in cell proliferation and increased the apoptosis of K1 cells. Cell cycle was arrested in both the S and G2/M phase. The levels of phosphorylated ERK1/2 and surviving were decreased after eIF3a knockdown.

CONCLUSION

Our study suggested that eIF3a contributed to TC cell proliferation. It may be a promising target for gene therapy in human thyroid cancer.

Gammacoronavirus Avian Infectious Bronchitis Virus and Alphacoronavirus Porcine Epidemic Diarrhea Virus Exploit a Cell-Survival Strategy via Upregulation of cFOS to Promote Viral Replication

Coronaviruses have evolved a variety of strategies to optimize cellular microenvironment for efficient replication. In this study, we report the induction of AP-1 transcription factors by coronavirus infection based on genome-wide analyses of differentially expressed genes in cells infected with avian coronavirus infectious bronchitis virus (IBV). Most members of the AP-1 transcription factors were subsequently found to be upregulated during the course of IBV and porcine epidemic diarrhea virus (PEDV) infection of cultured cells as well as in IBV-infected chicken embryos. Further characterization of the induction kinetics and functional roles of cFOS in IBV replication demonstrated that upregulation of cFOS at early to intermediate phases of IBV replication cycles suppresses IBV-induced apoptosis and promotes viral replication. Blockage of nuclear translocation of cFOS by peptide inhibitor NLSP suppressed IBV replication and apoptosis, ruling out the involvement of the cytoplasmic functions of cFOS in the replication of IBV. Furthermore, knockdown of ERK1/2 and inhibition of JNK and p38 kinase activities reduced cFOS upregulation and IBV replication. This study reveals an important function of cFOS in the regulation of coronavirus-induced apoptosis, facilitating viral replication.IMPORTANCE The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by a newly emerged zoonotic coronavirus (SARS-CoV-2), highlights the importance of coronaviruses as human and animal pathogens and our knowledge gaps in understanding the cellular mechanisms, especially mechanisms shared among human and animal coronaviruses, exploited by coronaviruses for optimal replication and enhanced pathogenicity. This study reveals that upregulation of cFOS, along with other AP-1 transcription factors, as a cell-survival strategy is such a mechanism utilized by coronaviruses during their replication cycles. Through induction and regulation of apoptosis of the infected cells at early to intermediate phases of the replication cycles, subtle but appreciable differences in coronavirus replication efficiency were observed when the expression levels of cFOS were manipulated in the infected cells. As the AP-1 transcription factors are multi-functional, further studies of their regulatory roles in proinflammatory responses may provide new insights into the pathogenesis and virus-host interactions during coronavirus infection.

G protein-coupled receptor kinase 2 modifies the cellular reaction to cisplatin through interactions with NADPH oxidase 4

G protein-coupled receptor kinases (GRKs), in addition to their role in modulating signal transduction mechanisms associated with activated G protein-coupled receptors (GPCRs), can also interact with many non-GPCR proteins to mediate cellular responses to chemotherapeutics. The rationale for this study is based on the presumption that GRK2 modulates the responses of cancer cells to the chemotherapeutic cisplatin. In this report, we show that GRK2 modulates the responses of cancer cells to cisplatin. Cervical cancer HeLa cells stably transfected with GRK2 shRNA, to decrease GRK2 protein expression, show increased sensitivity to cisplatin. Of interest, these cells also show increased accumulation of NADPH, associating with decreased NADP buildup, at low concentrations of cisplatin tested. These changes in NADPH and NADP levels are also observed in the breast cancer MDA MB 231 cells, which has lower endogenous GRK2 protein expression levels, but not BT549, a breast cancer cell line with higher GRK2 protein expression. This effect of NADPH accumulation may be associated with a decrease in NADPH oxidase 4 (NOX4) protein expression, which is found to correlate with GRK2 protein expression in cancer cells-a relationship which mimics that observed in cardiomyocytes. Furthermore, like in cardiomyocytes, GRK2 and NOX4 interact to form complexes in cancer cells. Collectively, these results suggest that GRK2 interacts with NOX4 to modify cisplatin sensitivity in cancer cells and may also factor into the success of cisplatin-based regimens.

Systems Pharmacology Study of the Anticervical Cancer Mechanisms of FDY003

Increasing data support that herbal medicines are beneficial in the treatment of cervical cancer; however, their mechanisms of action remain to be elucidated. In the current study, we used a systems pharmacology approach to explore the pharmacological mechanisms of FDY003, an anticancer herbal formula comprising Lonicera japonica Thunberg, Artemisia capillaris Thunberg, and Cordyceps militaris (Linn.) Link, in the treatment of cervical cancer. Through the pharmacokinetic assessment of absorption-distribution-metabolism-excretion characteristics, we found 18 active compounds that might interact with 106 cervical cancer-related targets responsible for the pharmacological effects. FDY003 targets were significantly associated with gene ontology terms related to the regulation of cellular behaviors, including cell proliferation, cell cycle processes, cell migration, cell apoptosis, cell death, and angiogenesis. The therapeutic targets of the herbal drug were further enriched in various oncogenic pathways that are implicated in the tumorigenesis and progression of cervical cancer, including the phosphatidylinositol 3-kinase, mitogen-activated protein kinase, focal adhesion, human papillomavirus infection, and tumor necrosis factor signaling pathways. Our study provides a systematic approach to explore the anticancer properties of herbal medicines against cervical cancer.

Guanine nucleotide-binding protein subunit beta-4 promotes gastric cancer progression via activating Erk1/2

Gastric cancer (GC) is one of the most common and lethal malignancies worldwide, and its poor prognosis is mainly due to the rapid tumor progression including tumor invasion, distant metastasis, etc. Understanding the molecular mechanisms regulating GC progression lays the basis for the development of targeted therapeutic agents. Increasing evidence suggests that guanine nucleotide-binding protein subunit beta-4 (GNB4), a key subunit of heterotrimeric G protein, plays a crucial role in the initiation and progression of multiple malignancies. However, whether and how GNB4 promotes GC progression are still unknown. In this study, we found that GNB4 was highly expressed in GC tissues compared to that in non-tumor tissues and was significantly associated with tumor invasion depth, pathological stage and poor survival rate of GC patients. Both gain-of-function and loss-of-function studies revealed that GNB4 significantly enhanced GC cell growth and motility both in vitro and in vivo. Further studies revealed that GNB4 overexpression induced G1-S transition and promoted the process of epithelial-mesenchymal transformation. These tumor promoting effects were mediated by GNB4 which activates the Erk1/2 pathway through upregulating Erk1/2 phosphorylation, as U0126, an Erk1/2 phosphorylation inhibitor, could significantly inhibit GNB4-mediated cell proliferation, migration and invasion. In summary, GNB4 contributes to the proliferation and metastasis of GC cells by activating the Erk1/2 signaling pathway, and it may serve as a potential therapeutic target of GC.

Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis

Background

Cervical cancer (CC) is one of the most common female malignancies over the world. Microtubule-associated protein 7 (MAP7) belongs to the family of microtubule-associated proteins (MAPs) which involve in microtubule dynamics and are critical in several important cellular and intracellular activities. This study aimed to investigate the expression and potential role of MAP7 in CC.

Methods

The expression level of MAP7 in CC tissues and normal tissues were analyzed using the data obtained from The cancer genomes atlas (TCGA) and genotype-tissue expression (GTEx) databases. The prognostic value of MAP7 in patients with CC was analyzed by Kaplan–Meier analysis, Univariate and Multivariate analyses. Moreover, the influences of MAP7 expression alteration on the viability and motility of Caski, HeLa and C-33A cells was measured by CCK8 assay, colony formation assay, scratch assay, and transwell migration and invasion assays. Flow cytometry was conducted to determine cell apoptosis. Western blot was performed to evaluate the impact of MAP7 on the expression of apoptotic-related proteins as well as mitogen-activated protein kinase (MAPK) signaling pathway-related proteins. In vivo tumorigenicity assay was performed to explore the influence of MAP7 on tumor growth.

Results

Up-regulation of MAP7 was observed in CC tissues and high MAP7 expression was positively correlated with worse prognosis. Multivariate analyses suggested that MAP7 expression can be served as an independent predictor for overall survival of patients with CC. Knockdown of MAP7 markedly suppressed Caski and HeLa cell viability, migration and invasion while notably induced cell apoptosis. Furthermore, depletion of MAP7 in Caski and HeLa cells elevated the expression levels of Active-caspase 3 and Bax, but declined the level of Bcl-2. Whilst, overexpression of MAP7 in C-33A cells presented the opposite outcomes. Additionally, knockdown of MAP7 significantly decreased the phosphorylation of mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) in Caski and HeLa cells, and overexpression of MAP7 increased their phosphorylation in C-33A cells, indicating that MAP7 may regulate the MAPK signaling pathway in CC cells. In vivo assays revealed that knockdown of MAP7 remarkably repressed the growth of CC tumors.

Conclusion

The results of the present study suggest that MAP7 functions as a promoter during the occurrence and progression of CC, and that MAP7 may serve as a promising therapeutic target in CC.

The effect of MEK1/2 inhibitors on cisplatin-induced acute kidney injury (AKI) and cancer growth in mice

In a clinically-relevant model of 4 week, low-dose cisplatin-induced AKI, mice were injected subcutaneously with non small cell lung cancer (NSCLC) cells that harbor an activating Kirsten rat sarcoma viral oncogene homolog (KRAS)^G12V mutation. Phospho extracellular signal-regulated kinase1/2 (pERK1/2) expression in kidney and tumors was decreased by the MEK1/2 inhibitors, U0126 and trametinib, that potently inhibit pERK1/2. U0126 resulted in a significant improvement in kidney function, acute tubular necrosis (ATN) and tubular cell apoptosis in mice with AKI. Genes that were significantly decreased by U0126 were heat shock protein 1, cyclin-dependent kinase 4 (CDK4) and stratifin (14-3-3σ). U0126 resulted in a significant decrease in tumor weight and volume and significantly increased the chemotherapeutic effect of cisplatin. Trametinib, a MEK1/2 inhibitor that is FDA-approved for the treatment of cancer, did not result in functional protection against AKI or worse AKI, but dramatically decreased tumor growth more than cisplatin. Smaller tumors in cisplatin or MEK1/2 inhibitor-treated mice were not related to changes in microtubule-associated proteins 1A/1B light chain 3B (LC3-II), p62, cleaved caspase-3, granzyme B, or programmed death-ligand 1 (PD-L1). In summary, despite ERK inhibition by both U0126 and trametinib, only U0126 protected against AKI suggesting that the protection against AKI by U0126 was due to an off-target effect independent of ERK inhibition. The effect of U0126 to decrease AKI may be mediated by inhibition of heat shock protein 1, CDK4 or stratifin (14-3-3σ). Trametinib was more effective than cisplatin in decreasing tumor growth, but unlike cisplatin, trametinib did not cause AKI.

SULF2 promotes tumorigenesis and inhibits apoptosis of cervical cancer cells through the ERK/AKT signaling pathway

The objective of this study was to explore the role of the SULF2-mediated ERK/AKT signaling pathway in cervical cancer. SULF2 expression was detected in tumor tissues and tumor-adjacent normal tissues from cervical cancer patients. HeLa cells were divided into six groups: control group, NC group, SULF2 siRNA group, SULF2 group, SULF2 + LY294002 group, and SULF2 + U0125 group. In each group, HeLa cells received the corresponding treatment, followed by measurement of the cellular biological characteristics and expression of the ERK/AKT signaling pathway. We also confirmed the effect of SULF2 in vivo using a xenograft model in nude mice. SULF2 was upregulated in cervical cancer tissues, which was specifically associated with the clinical stage, histological differentiation, and lymphatic metastasis. Compared to the control group, the SULF2 siRNA group displayed decreased expression of SULF2, concomitant with reduced proliferation, migration, and invasion, but there was an increase in the apoptosis rate of HeLa cells, as well as downregulation of the p-Akt/Akt, p-ERK/ERK, and Bax/Bcl-2 ratios and cyclin D1. Additionally, tumor growth was significantly inhibited in the xenograft model of nude mice. The results in the SULF2 group were quite the opposite in which SULF2 facilitated the growth of cervical cancer cells, which was reversed by LY294002 or U0126. SULF2 is highly expressed in cervical cancer, and thus, downregulation of SULF2 can inhibit the ERK1/2 and AKT signaling pathways to suppress the proliferation, invasion, and migration of cervical cancer cells while facilitating apoptosis.

Efficient miRNA Inhibitor with GO-PEI Nanosheets for Osteosarcoma Suppression by Targeting PTEN

BACKGROUND

Gene therapy is considered a novel way to treat osteosarcoma, and microRNAs are potential therapeutic targets for osteosarcoma. miR-214 has been found to promote osteosarcoma aggression and metastasis. Graphene oxide (GO) is widely used for gene delivery for the distinct physiochemical properties and minimal cytotoxicity.

METHODS

Polyethyleneimine (PEI)-functionalized GO complex was well-prepared and loaded with miR-214 inhibitor at different concentrations. The load efficacy was tested by gel retardation assay and the cy3-labeled fluorescence of cellular uptake. The experiments of wound healing, immunofluorescence staining, Western blot, qRT-PCR and immunohistochemical staining were performed to measure the inhibitory effect of the miR-214 inhibitor systematically released from the complexes against MG63, U2OS cells and xenograft tumors.

RESULTS

The systematic mechanistic elucidation of the efficient delivery of the miR-214 inhibitor by GO-PEI indicated that the inhibition of cellular miR-214 caused a decrease in osteosarcoma cell invasion and migration and an increase in apoptosis by targeting phosphatase and tensin homolog (PTEN). The synergistic combination of the GO-PEI-miR-214 inhibitor and CDDP chemotherapy showed significant cell death. In a xenograft mouse model, the GO-PEI-miR-214 inhibitor significantly inhibited tumor volume growth.

CONCLUSION

This study indicates the potential of functionalized GO-PEI as a vehicle for miRNA inhibitor delivery to treat osteosarcoma with low toxicity and miR-214 can be a good target for osteosarcoma therapy.

LncRNA HEIH Enhances Paclitaxel-Tolerance of Endometrial Cancer Cells via Activation of MAPK Signaling Pathway

This study aimed to investigate the function of lncRNA HEIH on promoting endometrial cancer cells' tolerance of paclitaxel (PTX). LncRNA HEIH expression was measured by QRT-PCR in endometrial cancer tissues, human healthy tissues and cell lines. The PTX-resistant endometrial cancer cells (Ishikawa-RE and HHUA-RE) were intermittently exposed to increase concentrations of PTX and were constructed as evidenced by MTT assay. Besides, the specific siRNA of HEIH (siHEIH) and pcDNA3.1-HEIH plasmid transfection were utilized to alter the expression of HEIH in the cells and investigate the effects of HEIH on resistance to PTX in endometrial cancer cells. Moreover, MTT, colony formation and apoptosis analysis were taken advantage to evaluate cell viability and proliferation when treated with PTX. Then, differential genes in PTX-resistant and HEIH-knock-down PTX-resistant endometrial cancer cells were screened out by microarray analysis. Finally, gene-set enrichment analysis was used to predict the promising signaling pathway of HEIH and western blotting analysis were performed to verify the relevant genes expression of MAPK signaling pathway. LncRNA HEIH, the dysregulation of which involved in production of drug-resistance, was overexpressed in PTX-resistant endometrial cancer cells. Up-regulating HEIH would activate MAPK pathway, promote chemo-resistance of endometrial cancer cells and enhance cell proliferation and viability, whereas silencing HEIH depressed the MAPK signaling pathway, contributed to restoring chemo-sensitivity to PTX and repressed cell physiological process. Down-regulating lncRNA HEIH expression reversed the PTX-resistance of endometrial cancer cells through MAPK signaling pathway.

MiR-361-5p inhibits cell proliferation and induces cell apoptosis in retinoblastoma by negatively regulating CLDN8

PURPOSE

MiR-361-5p has been reported to act as tumor suppressor in several types of cancers. Retinoblastoma (RB) is the most common ocular tumor in childhood. The current study aimed to investigate the expression pattern and biological function of miR-361-5p in RB.

METHODS

Quantitative real time was utilized to determine and compare the expression of miR-361-5p in RB cells and normal retinal pigment epithelial cell line ARPE-19. CCK-8 and Edu assay were performed to assess cell proliferation. Cell apoptosis was evaluated using flow cytometry assay. Bioinformatics databases and luciferase reporter assay were applied to predict and confirm the target gene of miR-361-5p in RB cells.

RESULTS

Here, we found miR-361-5p was significantly downregulated in RB cells compared with normal retinal pigment epithelial cell line ARPE-19. MiR-361-5p overexpression significantly inhibited or silencing promoted cell proliferation in Y79 and SO-RB50 cells, respectively. Flow cytometry assay showed a significantly decreased cell apoptosis in miR-361-5p silencing Y79 cells and increased cell apoptosis in miR-361-5p overexpressing SO-RB50 cells. Moreover, miR-361-5p directly bound to the 3' untranslated region of claudin 8 (CLDN8) and inhibited the expression of CLDN8. Furthermore, we found knockdown of CLDN8 photocopied the effect of miR-361-5p on cell proliferation and apoptosis in RB cells.

CONCLUSION

These results indicated that overexpression of miR-361-5p might act as a suppressor in RB by targeting CLDN8 to inhibit the cellular function.

Correlation between the rs7101 and rs1063169 polymorphisms in the FOS noncoding region and susceptibility to and prognosis of colorectal cancer

BACKGROUND

The FOS gene is located on human chromosome 14q21-31 and encodes the nuclear oncoprotein c-Fos. This study analyzed the correlation between the FOS noncoding region rs7101 and rs1063169 polymorphisms and colorectal cancer susceptibility and prognosis.

METHODS

We analyzed the FOS genotypes in 432 colorectal cancer patients and 315 healthy subjects by PCR/Sanger sequencing. Survival was analyzed by Kaplan-Meier and Cox regression analysis. Western blot was used to detect the expression of c-Fos protein in cancer tissues and adjacent tissues in colorectal cancer patients with different genotypes.

RESULTS

The presence of a T allele at rs7101 and a T allele at rs1063169 in FOS carried a higher risk of colorectal cancer [adjusted odds ratio (OR) = 1.237, 95% confidence interval (95% CI) = 1.131-1.346, P ≤ .001 and adjusted OR = 1.218, 95% CI = 1.111-1.327, P ≤ .001, respectively]. c-Fos protein levels were significantly higher in variant cancer tissues than in normal mucosa tissues (P < .05), and c-Fos proteins levels were also higher in homozygous variant cancer tissues than in heterozygous variant cancer tissues. The 3-year survival rate of patients with wild-type FOS was higher than that of patients with variant FOS (P < .05).

CONCLUSION

The rs7101 and rs1063169 polymorphisms in the noncoding region of FOS are associated with the risk of developing colorectal cancer and the progression of colorectal cancer, which may be because the mutation enhances the expression of c-Fos protein to promote the incidence and development of colorectal cancer.

Erianin inhibits human cervical cancer cell through regulation of tumor protein p53 via the extracellular signal-regulated kinase signaling pathway

Erianin, a natural bibenzyl compound, is present in Dendrobium chrysotoxum Lindl. (commonly known as Shihu in China), which is used as an antipyretic and analgesic in traditional Chinese medicine, and has been reported to exert inhibitory effects on cancer cells in vitro. Cervical cancer is the third-most common cancer in women worldwide, and has the highest morbidity rate of gynecological malignancies. Thus, the identification of effective chemotherapeutical agents to treat this disease is urgent. The aim of the present study was to elucidate the biological functions and molecular mechanism of erianin on HeLa cells. Cellular proliferation was assessed using an MTT assay and flow cytometry assay with propidium iodide (PI) staining. Apoptosis rates were observed using a high content screening system via annexin V-fluorescein isothiocyanate/PI double staining, and measured by flow cytometry. The protein levels of tumor protein p53, extracellular signal-regulated kinase 1/2 (ERK1/2), caspase-3, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X (Bax) were assessed by western blot analysis. Erianin inhibited the growth of HeLa cells and induced apoptosis in a dose- and time-dependent manner, inducing cell cycle arrest at the G₂/M stage. Erianin treatment also increased the expression of Bax and caspase-3, but decreased levels of Bcl-2 and phosphorylated-ERK1/2. Cells treated with paclitaxel were regarded as the positive group. Together, the results of the present study indicated that erianin could be considered as an effective drug candidate; in HeLa cells it inhibited cellular proliferation and promoted apoptosis via regulation of the ERK1/2 signaling and mitochondrial-based apoptosis pathways. Thus, erianin has the promise to be developed further for cervical cancer therapy.

Effect of lentiviral vector-mediated KSR1 gene silencing on the proliferation of renal tubular epithelial cells and expression of inflammatory factors in a rat model of ischemia/reperfusion injury

Renal ischemia/reperfusion (I/R) is a common cause of acute renal failure in many clinical settings. Our study aimed to elucidate the role of lentiviral vector-mediated KSR1 gene silencing in inflammatory factor expression and proliferation of renal tubular epithelial cells (RTECs) in a rat model of I/R injury. Male Sprague-Dawley (SD) rats were used for I/R model establishment and subject to different treatments, followed by the measurement of neurological severity score (NSS), tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, 47-kDa heat-shock protein (HSP47), KSR1, and factors related to the Ras/MAPK pathway, as well as cell apoptosis. As compared with the blank group, the neurologic impairment induced by I/R in the siKSR1, U0126, and siKSR1 + U0126 groups was alleviated. Compared with the control group, the other five groups showed increased levels of TNF-α, IL-6, IL-1β, HSP47, N-ras, Raf-1, c-fos, TNF-α, IL-6, p38 MAPK, and cell apoptosis, accompanied by a declined mRNA and protein level of Bcl-2. As compared with the blank and NC groups, the siKSR1, U0126, and siKSR1 + U0126 groups showed decreased levels of TNF-α, IL-6, IL-1β, HSP47, N-ras, Raf-1, c-fos, TNF-α, IL-6, p38 MAPK, cleaved caspase-3, cleaved caspase-9, p53, and cell apoptosis, accompanied by an increased mRNA and protein level of Bcl-2. Our findings demonstrated that KSR1 gene silencing might inhibit the expression of inflammatory factors in RTECs and promote their proliferation by inactivating the Ras/MAPK pathway in the rat model of I/R injury.

Retracted: MicroRNA-92a promotes tumor growth and suppresses immune function through activation of MAPK/ERK signaling pathway by inhibiting PTEN in mice bearing U14 cervical cancer

Cervical cancer is known as the possible outcome of genital infection, while the molecular mechanisms of initiation, development, and metastasis of cervical cancer have not yet been fully elucidated. Our study aims to investigate the effects of microRNA-92a (miR-92a) on tumor growth and immune function by targeting PTEN via the MAPK/ERK signaling pathway in tumor-bearing mice. C57BL/6 female mice were used for tumor-bearing mouse models and their tumor and adjacent normal tissues were collected, and normal cervical tissues were obtained from normal mice. Serum levels of tumor necrosis factor-α (TNF-α) and soluble interleukin-2 receptor (sIL-2R) were detected by ELISA. The cells were divided into the normal, blank, negative control (NC), miR-92a mimic, miR-92a inhibitor, siRNA-PTEN, and miR-92a inhibitor + siRNA-PTEN groups. Dual-luciferase reporter assay was adopted to determine the relationship between PTEN and miR-92a. Expressions of miR-92a, PTEN, TNF-α, sIL-2R, ERK1, and ERK2 were tested by RT-qPCR and Western blotting. Cell proliferation was detected by cell count kit-8 (CCK-8); cell cycle and apoptosis were detected by flow cytometry. Compared with the normal cervical tissues and adjacent normal tissues, the cervical cancer tissues exhibited increased expressions of miR-92a, p-ERK1/2, and serum levels of TNF-α and sIL-2R while decreased PTEN expression. PTEN was confirmed to be the target gene of miR-92a. As compared with the blank and NC groups, expressions of miR-92a, ERK1 and ERK2 increased, and expressions of PTEN decreased in the miR-92a mimic group. The miR-92a mimic group exhibited increased expression levels of TNF-α and sIL-2R, cell proliferation, and cell number in S phase but decreased cell apoptosis, and cell number in G0/G1 phase, while the miR-92a inhibitor group followed opposite trends. miR-92a promotes tumor growth and suppresses immune function by inhibiting PTEN via activation of the MAPK/ERK signaling pathway in mice bearing U14 cervical cancer.

Regulator of chromatin condensation 1 abrogates the G1 cell cycle checkpoint via Cdk1 in human papillomavirus E7-expressing epithelium and cervical cancer cells

Regulator of chromatin condensation 1 (RCC1) is a major guanine-nucleotide exchange factor for Ran GTPase and plays key roles in nucleo-cytoplasmic transport, mitosis, and nuclear envelope assembly. RCC1 is known to be a critical cell cycle regulator whose loss causes G1 phase arrest, but the molecular basis for this regulation is poorly understood. Furthermore, little is known about the relationship between RCC1 and carcinomas. Human papillomavirus (HPV) infection is highly associated with the development of cervical cancer. The expression and function of RCC1 in HPV-related cervical cancer and cell cycle regulation have not yet been explored. In this study, we first observed that RCC1 immunostaining was mildly increased in cervical cancer tissues and significantly upregulated in HPV E7-expressing cells; this localization was primarily nuclear. We showed that the transcription factor c-Jun transcriptionally upregulates RCC1 via a direct interaction with the RCC1 promoter. Moreover, siRNA-mediated knockdown of RCC1 inhibited G1/S cell cycle progression and DNA synthesis, while overexpression of RCC1 abrogated the G1 checkpoint. RCC1 knockdown downregulated the protein levels of the transcription factor E2F1, especially nuclear E2F1, by promoting its degradation in HPV E7-expressing cells. Overexpression of E2F1 rescued RCC1 knockdown-mediated inhibition of G1/S progression. Additionally, we showed that cyclin-dependent kinase 1 (Cdk1), a known target of E2F1, is involved in G1 checkpoint regulation, as Cdk1 knockdown hindered G1/S progression, while Cdk1 overexpression rescued RCC1 knockdown-mediated effect on G1 cell cycle progression. Furthermore, RCC1 knockdown reduced HPV E7 protein levels, which may in turn downregulate E2F1. Our study explores the function of RCC1 in G1/S cell cycle progression and suggests that RCC1 may be involved in HPV E7-mediated genomic instability.

c-Fos over-expression promotes radioresistance and predicts poor prognosis in malignant glioma

c-Fos is a major component of activator protein (AP)-1 complex. It has been implicated in cell differentiation, proliferation, angiogenesis, invasion, and metastasis. To investigate the role of c-Fos in glioma radiosensitivity and to understand the underlying molecular mechanisms, we downregulated c-Fos gene expression by lentivirus-mediated shRNA in glioma cell lines and subsequently analyzed the radiosensitivity, DNA damage repair capacity, and cell cycle distribution. Finally, we explored its prognostic value in 41 malignant glioma patients by immunohistochemistry. Our results showed that silencing c-Fos sensitized glioma cells to radiation by increasing radiation-induced DNA double strand breaks (DSBs), disturbing the DNA damage repair process, promoting G2/M cell cycle arrest, and enhancing apoptosis. c-Fos protein overexpression correlated with poor prognosis in malignant glioma patients treated with standard therapy. Our findings provide new insights into the mechanism of radioresistance in malignant glioma and identify c-Fos as a potentially novel therapeutic target for malignant glioma patients.

C-fos upregulates P-glycoprotein, contributing to the development of multidrug resistance in HEp-2 laryngeal cancer cells with VCR-induced resistance

Background

Laryngeal cancer tends to have a very poor prognosis due to the unsatisfactory efficacy of chemotherapy for this cancer. Multidrug resistance (MDR) is the main cause of chemotherapy failure. The proto-oncogene c-fos has been shown to be involved in the development of MDR in several tumor types, but few studies have evaluated the relationship between c-fos and MDR in laryngeal cancer. We investigated the role of c-fos in MDR development in laryngeal cancer cells (cell line: human epithelial type 2, HEp-2) using the chemotherapeutic vincristine (VCR).

Methods

HEp-2/VCR drug resistance was established by selection against an increasing drug concentration gradient. The expressions of c-fos and multidrug resistance 1 (mdr1) were measured using qPCR and western blot. C-fos overexpression or knockdown was performed in various cells. The intracellular rhodamine-123 (Rh-123) accumulation assay was used to detect the transport capacity of P-glycoprotein (P-gp, which is encoded by the mdr1 gene).

Results

HEp-2 cells with VCR-induced resistance (HEp-2/VCR cells) were not only resistant to VCR but also evolved cross-resistance to other chemotherapeutic drugs. The expressions of the c-fos and mdr1genes were significantly higher in the HEp-2/VCR cells than in control cells. C-fos overexpression in HEp-2 cells (c-fos WT) resulted in increased P-gp expression and increased the IC₅₀ for 5-FU. C-fos knockdown in the HEp-2/VCR cells (c-fos shRNA) resulted in decreased P-gp expression and decreased IC₅₀ for 5-FU. An intracellular Rh-123 accumulation assay showed that the mean intracellular fluorescence intensity (MFI) was lower in the HEp-2/VCR cells than in HEp-2 cells. C-fos WT cells also showed lower MFI. By contrast, c-fos shRNA cells exhibited a higher MFI than the control group.

Conclusion

C-fos increased the expression of P-gp and mdr1 in the HEp-2/VCR cells, and enhanced the efflux function of the cells, thereby contributing to the development of MDR.

Elevated Expression of Kin17 in Cervical Cancer and Its Association With Cancer Cell Proliferation and Invasion

BACKGROUND

Cervical cancer is one of the most common cancers in women worldwide. Emerging evidence suggests that kin17 is a tumor-promoting protein in some types of solid tumors. However, whether kin17 contributes to cervical cancer carcinogenesis remains unknown.

METHODS

Kin17 expression in clinical samples from Guangdong Women and Children's Hospital and Health Institute was detected by immunohistochemical staining. A series of functional experiments including 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, 5-bromo-2'-deoxyuridine assay, colony formation, transwell assay, flow cytometry of apoptosis, and cell cycle were performed to explore the roles of kin17 in cervical cancer cells HeLa.

RESULTS

In this study, we showed for the first time that the expression of kin17 was significantly increased in clinical cervical cancer samples, and associated with tumor differentiation, lymph node metastasis, and ki-67 expression in a clinicopathologic characteristics review. Furthermore, silence of kin17 in HeLa cells inhibited cell proliferation, clone formation, cell cycle progression, migration, and invasion, and also promoted cell apoptosis.

CONCLUSION

Our findings demonstrate that kin17 is closely related to the cell proliferation and invasion of cervical cancer and could be a novel diagnostic and therapeutic target for cervical cancer management. The underlying mechanisms should be elucidated in future research.

Fluorochloridone induces primary cultured Sertoli cells apoptosis: Involvement of ROS and intracellular calcium ions-mediated ERK1/2 activation

Fluorochloridone (FLC) is a widely used pyrrolidone selective herbicide and reported to induce testis injuries in male rats, but the underlying mechanism is largely unknown. In the present study, primary-cultured Sertoli cells were exposed to FLC at the concentration of 0-10.00μM to study the mechanism of FLC-induced apoptosis. The roles of ROS, intracellular calcium, endoplasmic reticulum (ER), and ERK1/2 were looked at with ROS scavenger N-acetyl-cysteine (NAC), intracellular calcium chelator BAPTA-AM, ER calcium depleting agent thapsigargin (TG), and ERK1/2 inhibitor U0126, respectively. FLC induced dose-dependent apoptosis increase as well as the elevation in levels of ROS, intracellular calcium, and ERK1/2 activation. FLC treatment led to constantly increasing apoptotic rates and ERK1/2 activation over time, while inversed-V shaped change tendencies of ROS and intracellular calcium levels were observed. FLC-induced ROS generation disrupted the intracellular calcium homeostasis by attacking the ER, and the elevated intracellular calcium levels resulted in ERK1/2 over-phosphorylation and consequently promoted Sertoli cell apoptosis. Taken together, ROS and intracellular calcium-mediated ERK1/2 activation led to FLC-induced Sertoli cell apoptosis.

Oxidative stress regulates mitogen‑activated protein kinases and c‑Jun activation involved in heat stress and lipopolysaccharide‑induced intestinal epithelial cell apoptosis

Heat stress and gut‑derived endotoxinemia are common causes of multiple organ dysfunction syndrome in heat stroke patients. Evidence has demonstrated that cell apoptosis in the small intestine serves an important role in the pathogenesis of heatstroke, which leads to increased intestinal permeability to endotoxin or lipopolysaccharides (LPS) from the gut entering the circulation. However, little is known about the potential underlying mechanisms mediating heat stress combined with LPS‑induced intestinal epithelial cell apoptosis. In the present study, LPS combined with heat stress induced production of reactive oxygen species (ROS), mitochondrial membrane potential disruption and cell apoptosis, which eventually led to increased intestinal permeability and reduced epithelial resistance in the IEC‑6 cell line. Inductions in ROS, mitochondrial membrane potential disruption and cell apoptosis were detected by using an ROS assay kit, 5,5',6,6'‑tetrachloro‑1,1',3,3'tetraethylbenzimidazo carbocyanine iodide dye kit and annexin V‑fluorescein isothiocyanate apoptosis kit, respectively. The effect of ROS on mitogen activated protein kinases (MAPKs) and c‑Jun activation was investigated using the antioxidant drug, butylated hydroxyanisole (BHA) by western blotting. The results of the present study demonstrated that ROS is essential to activate p38, extracellular signal‑regulated kinase (ERK) and c‑Jun, but not c‑Jun N‑terminal kinase (JNK), in LPS combined with heat stress treated cells. Furthermore, ROS, and activation of p38, JNK and c‑Jun, were revealed to serve pro‑apoptosis roles which aggravated damage to epithelial barrier integrity, as assessed by flow cytometry using Annexin V‑fluorescein isothiocyanate staining and pretreatment of cells with specific inhibitors of ROS, JNK, p38 and c‑Jun (BHA, SP600125, SB203580 and c‑Jun peptide, respectively). Transepithelial electrical resistance and horseradish peroxidase permeability were detected in cells treated with LPS combined with heat stress, which revealed that ERK serves an anti‑apoptosis role, as determined by pretreatment of cells with PD98059, a specific inhibitor of ERK. In conclusion, these findings suggested a novel role of the ROS signaling pathway which involved activation of MAPKs and c‑Jun, following LPS combined with heat stress‑induced IEC‑6 cell apoptosis and impairment of the epithelial barrier. These results may facilitate understanding of pathological conditions involving ROS, such as heat stroke.

Liposome-mediated RNA interference delivery against Erk1 and Erk2 does not equally promote chemosensitivity in human hepatocellular carcinoma cell line HepG2

BACKGROUND

Extracellular signal-regulated kinase (Erk)1 and Erk2 are central mediators of mitogen-activated protein kinase signaling pathway, which plays a key role in proliferation and chemoresistance of cancer cells. However, the effect of Erk1 and Erk2 in these processes may not be the same. The aim of this study was to investigate differential effect of Erk1 and Erk2 down-regulation on chemoresistance in human hepatocellular carcinoma (HCC) cells. Expression level and relative expression analysis in HepG2 cells were performed using RT-PCR and qRT-PCR, respectively. Phosphorylated-Erk1/2 and apoptosis analysis was performed by flow-cytometry (FCM) technique.

RESULTS

The results showed a higher expression level of Erk2 relative to Erk1 in HepG2 cells (P < 0.01). A significant decrease in phosphorylated-Erk1/2 and a compensational response was observed after Erk1 and/or Erk2 silencing using specific small interfering ribonucleic acids (siRNAs) (P < 0.01). Furthermore, 5-fluorouracil (5-FU) chemotherapy following siRNA-mediated knockdown lead to a significant enhancement of chemosensitivity with a higher rate of early apoptosis in Erk2 silencing relative to that of Erk1) + 9%, P < 0.01). 5-FU treatment after dual knockdown of Erk1/2 showed higher rate of early apoptosis relative to single Erk1 silencing (+9.25%, P < 0.01) and also higher rate of late apoptosis compared to single Erk1 and Erk2 silencing (+4.96% and +4.66%, P < 0.01).

CONCLUSION

Our data show that liposomal siRNA-mediated down-regulation of Erk1/2 can lead to potent chemosensitizing effects in HepG2 cells. Moreover, a higher chemosensitivity following Erk2 down-regulation than Erk1 down-regulation may be associated with the higher expression of Erk2 in human HCC.

Suppressive effect of microRNA-143 in retinoblastoma

AIM

To investigate microRNA-143 expression and effect on suppression of retinoblastoma (RB) cells.

METHODS

The expression of microRNA-143 was investigated and compared in normal human retina tissue samples and in RB cell lines of Y79 and Weri1. The microRNA-143 mimics were transfected into the RB cell lines separately, and its effect on RB cell lines was detected using reverse-transcription quantitative polymerase chain reaction and Western blotting methods.

RESULTS

The microRNA-143 expression was significantly suppressed in RB cell lines. Overexpression of microRNA-143 significantly lowered cell viability and invasion of the RB cell lines, and increased the number of apoptotic cells. Meanwhile, the Bax expression was up-regulated and much higher in the microRNA-143 mimics transfected group than that in the negative control and the microRNA-143 inhibitor groups.

CONCLUSION

MicroRNA-143 exhibits suppressive effects in RB. The current study provides the perspective of a potential therapeutic treatment for RB.

CXCL13 Promotes Proliferation of Mesangial Cells by Combination with CXCR5 in SLE

As a CXC subtype member of the chemokine superfamily, CXCL13 is considered to be involved in systemic lupus erythematosus (SLE), especially in lupus nephritis (LN). To determine the effect of CXCL13 on SLE and explore the potential mechanisms, we tested serum concentrations of CXCL13 in patients and healthy individuals and found that CXCL13 expression was high in SLE patients especially in LN patients. When we treated human renal mesangial cells (HRMCs) in vitro with recombinant human CXCL13, the cell proliferation was accelerated, which was tested by Cell Counting Kit-8 assay and flow cytometry. Western blot and immunofluorescence assay revealed that CXCL13 would lead to phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). However, the effect was weakened after the silence of CXCR5. The results of our study elaborated that high expression of CXCL13 could be involved in the pathogenesis of LN.

miR-143 is associated with proliferation and apoptosis involving ERK5 in HeLa cells

Inappropriate expression of microRNA (miR) is strongly associated with carcinogenesis. miR-143 was reported to be one of the most prominent miRs implicated in the genesis and progression of human cancer. However, its correlation with cell proliferation and apoptosis in cervical cancer remains to be fully elucidated. In the present study, it was demonstrated that miR-143 is able to suppress the proliferation of cervical cancer HeLa cells and induce cell apoptosis in a time- and dose-dependent manner. The present study also investigated the potential targets of miR-143, extracellular-signal-regulated kinase 5 (ERK5) and its downstream substrate oncoprotein c-Fos, both of which are involved in cell proliferation and apoptosis. Upon increasing the miR-143 level, the ERK5 and c-Fos protein expression was significantly decreased without the effect of ERK5 transcription. Therefore, miR-143 is able to suppress cell proliferation and induce apoptosis in HeLa cells, potentially through negative regulation of ERK5 at its post-transcriptional stage.