PI3K/Akt/HIF-1α signaling pathway mediates HPV-16 oncoprotein-induced expression of EMT-related transcription factors in non-small cell lung cancer cells

The association between human papillomavirus and lung cancer: A Mendelian randomization study

BACKGROUND

To investigate the causal relationship between human papillomavirus (HPV) and lung cancer, we conducted a study using the two-sample Mendelian randomization (TSMR).

METHOD

Data from genome-wide association studies (GWAS) were analyzed with HPV E7 Type 16 and HPV E7 Type 18 as exposure factors. The outcome variables included lung cancer, small cell lung cancer, adenocarcinoma and squamous cell lung cancer. Causality was estimated using inverse variance weighted (IVW), MR-Egger and weighted median methods. Heterogeneity testing, sensitivity analysis, and multiple validity analysis were also performed..

RESULTS

The results showed that HPV E7 Type 16 infection was associated with a higher risk of squamous cell lung cancer (OR = 7.69; 95% CI:1.98-29.85; p = 0.0149). HPV E7 Type 18 infection significantly increased the risk of lung adenocarcinoma (OR = 0.71; 95% CI: 0.38-1.31; p = 0.0079) and lung cancer (OR = 7.69; 95% CI:1.98-29.85; p = 0.0292). No significant causal relationship was found between HPV E7 Type 16 and lung adenocarcinoma, lung cancer, or small cell lung carcinoma, and between HPV E7 Type 18 and squamous cell lung cancer or small cell lung carcinoma.

CONCLUSIONS

This study has revealed a causal relationship between HPV and lung cancers. Our findings provide valuable insights for further mechanistic and clinical studies on HPV-mediated cancer.

The cellular-centered view of hypoxia tumor microenvironment: Molecular mechanisms and therapeutic interventions

Cancer is a profoundly dynamic, heterogeneous and aggressive systemic ailment, with a coordinated evolution of various types of tumor niches. Hypoxia plays an indispensable role in the tumor micro-ecosystem, drastically enhancing the plasticity of cancer cells, fibroblasts and immune cells and orchestrating intercellular communication. Hypoxia-induced signals, particularly hypoxia-inducible factor-1α (HIF-1α), drive the reprogramming of genetic, transcriptional, and proteomic profiles. This leads to a spectrum of interconnected processes, including augmented survival of cancer cells, evasion of immune surveillance, metabolic reprogramming, remodeling of the extracellular matrix, and the development of resistance to conventional therapeutic modalities like radiotherapy and chemotherapy. Here, we summarize the latest research on the multifaceted effects of hypoxia, where a multitude of cellular and non-cellular elements crosstalk with each other and co-evolve in a synergistic manner. Additionally, we investigate therapeutic approaches targeting hypoxic niche, encompassing hypoxia-activated prodrugs, HIF inhibitors, nanomedicines, and combination therapies. Finally, we discuss some of the issues to be addressed and highlight the potential of emerging technologies in the treatment of cancer.

The emerging role of human papillomavirus in lung cancer

Lung cancer stands as one of the most lethal diseases and is the foremost cause of cancer-related mortalities worldwide. The pathophysiology of lung cancer is multifaceted, and it includes multiple cell signaling pathways and other complex factors such as oxidative stress and genetics. The association of HPV with lung carcinogenesis was first proposed in 1979, and since then, scientists worldwide have been putting forward several hypotheses to establish a relationship between this virus and lung cancer. Although studies have reported the presence of HPV in lung cancer, the exact mechanism of entry and the route of transmission have not been elucidated clearly till date. Numerous studies across the globe have detected differentially expressed HPV oncoproteins in lung cancer patients and found their association with the critical cell signaling pathways that leads to the development and progression of lung cancer. Many reports have also provided evidence stating the involvement of HPV in determining the survival status of lung cancer patients. The present review recapitulates the studies evincing the association of HPV and lung cancer, its route of transmission and mechanism of action; the detection of the virus and treatment opportunities for HPV-positive lung cancer; and the severity associated with this disease. Therefore, this will provide an explicit idea and would help to develop preventive measures and specific as well as effective treatment for HPV-associated lung carcinogenesis.

The risk for subsequent primary lung cancer after cervical carcinoma: A quantitative analysis based on 864,627 cases

PURPOSE

To compare the risk of developing subsequent primary lung cancer among cervical cancer patients and the general population.

METHODS

Several databases were searched from inception to April 25, 2023. The standard incidence ratios (SIRs) with 95% confidence intervals (CIs) were combined to identify the risk for second primary lung cancer after cervical carcinoma. Subgroup analyses based on the follow-up period, age, degree of malignancy and source of SIR were conducted. All the statistical analyses were performed with STATA 15.0 software.

RESULTS

A total of 22 retrospective studies involving 864,627 participants were included. The pooled results demonstrated that cervical cancer patients had a significantly greater risk for lung cancer than did the general population (SIR = 2.63, 95% CI: 2.37-2.91, P<0.001). Furthermore, subgroup analyses stratified by follow-up period (<5 years and ≥5 years), age (≤50 years and <50 years), and degree of malignancy (invasive and in situ) also revealed an increased risk of developing lung cancer among cervical carcinoma patients.

CONCLUSION

Cervical cancer patients are more likely to develop subsequent primary lung cancer than the general population, regardless of age, follow-up time or degree of malignancy. However, more high-quality prospective studies are still needed to verify our findings.

The Role of Human Papilloma Virus (HPV) in Primary Lung Cancer Development: State of the Art and Future Perspectives

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. Notably, the incidence of lung cancer among never-smokers, predominantly women, has been rising in recent years. Among the various implicated risk factors, human papilloma virus (HPV) may play a role in the development of NSCLC in a certain subset of patients. The prevalence of high-risk HPV-DNA within human neoplastic lung cells varies across the world; however, the carcinogenetic role of HPV in NSCLC has not been completely understood. Bloodstream could be one of the routes of transmission from infected sites to the lungs, along with oral (through unprotected oral sex) and airborne transmission. Previous studies reported an elevated risk of NSCLC in patients with prior HPV-related tumors, such as cervical, laryngeal, or oropharyngeal cancer, with better prognosis for HPV-positive lung cancers compared to negative forms. On the other hand, 16% of NSCLC patients present circulating HPV-DNA in peripheral blood along with miRNAs expression. Typically, these patients have a poorly differentiated NSCLC, often diagnosed at an advanced stage. However, HPV-positive lung cancers seem to have a better response to target therapies (EGFR) and immune checkpoint inhibitors and show an increased sensitivity to platinum-based treatments. This review summarizes the current evidence regarding the role of HPV in NSCLC development, especially among patients with a history of HPV-related cancers. It also examines the diagnostic and prognostic significance of HPV, investigating new future perspectives to enhance cancer screening, diagnostic protocols, and the development of more targeted therapies tailored to specific cohorts of NSCLC patients with confirmed HPV infection.

Carcinogenic Role and Clinical Significance of Histone H3-H4 Chaperone Anti-silencing Function 1 B (ASF1B) in Lung Adenocarcinoma

Histone H3-H4 chaperone anti-silencing function 1 (ASF1) plays an important role in the polymerization, transport, and modification of histones. However, the significance of ASF1B in lung adenocarcinoma (LUAD) is largely overlooked. We investigated the aberrant expression of ASF1B in LUAD and its potential link to patient survival using multiple databases. ASF1B-overexpressing and knockdown cell lines were constructed to explore its effects on the biological behavior of lung cancer cells. ssGSEA, TMB, TIDE and IMvigor210 cohort were used to explore and validate the association of ASF1B to tumor immunity. Our data suggested that ASF1B was overexpressed in LUAD, and was associated with poor prognosis. ASF1B promoted the proliferation, migration, and invasion of lung cancer cells by regulating the phosphorylation of AKT in vitro. ASF1B was associated with tumor immunity. In summary, ASF1B may promote malignant behavior of LUAD cells, and its overexpression correlates with worse prognosis and better immunotherapy effect.

HPV E6/E7: insights into their regulatory role and mechanism in signaling pathways in HPV-associated tumor

Human papillomavirus (HPV) is a class of envelope-free double-stranded DNA virus. HPV infection has been strongly associated with the development of many malignancies, such as cervical, anal and oral cancers. The viral oncoproteins E6 and E7 perform central roles on HPV-induced carcinogenic processes. During tumor development, it usually goes along with the activation of abnormal signaling pathways. E6 and E7 induces changes in cell cycle, proliferation, invasion, metastasis and other biological behaviors by affecting downstream tumor-related signaling pathways, thus promoting malignant transformation of cells and ultimately leading to tumorigenesis and progression. Here, we summarized that E6 and E7 proteins promote HPV-associated tumorigenesis and development by regulating the activation of various tumor-related signaling pathways, for example, the Wnt/β-catenin, PI3K/Akt, and NF-kB signaling pathway. We also discussed the importance of HPV-encoded E6 and E7 and their regulated tumor-related signaling pathways for the diagnosis and effective treatment of HPV-associated tumors.

Virus infection participates in the occurrence and development of human diseases through monoamine oxidase

Monoamine oxidase (MAO) is a membrane-bound mitochondrial enzyme that maintains the steady state of neurotransmitters and other biogenic amines in biological systems through catalytic oxidation and deamination. MAO dysfunction is closely related to human neurological and psychiatric diseases and cancers. However, little is known about the relationship between MAO and viral infections in humans. This review summarises current research on how viral infections participate in the occurrence and development of human diseases through MAO. The viruses discussed in this review include hepatitis C virus, dengue virus, severe acute respiratory syndrome coronavirus 2, human immunodeficiency virus, Japanese encephalitis virus, Epstein-Barr virus, and human papillomavirus. This review also describes the effects of MAO inhibitors such as phenelzine, clorgyline, selegiline, M-30, and isatin on viral infectious diseases. This information will not only help us to better understand the role of MAO in the pathogenesis of viruses but will also provide new insights into the treatment and diagnosis of these viral diseases.

Exosomal epidermal growth factor receptor is involved in HPV-16 E7-induced epithelial-mesenchymal transition of non-small cell lung cancer cells: A driver of signaling in vivo?

Our previous studies have demonstrated that human papillomavirus (HPV)-16 E7 oncoprotein promoted epithelial-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) cells. Moreover, recent studies have found that exosomes can mediate EMT of NSCLC cells and epidermal growth factor receptor (EGFR) is related to the progression of NSCLC. Here, we further investigated the role of exosomal EGFR in HPV-16 E7-induced EMT of NSCLC cells. Our results showed that the exosomes derived from the stable HPV-16 E7-overexpressing A549 and NCI-H460 NSCLC cells (E7 Exo) significantly increased migration, invasion, and proliferation abilities of NSCLC cells as compared with the exosomes derived from empty vector-infected NSCLC cells (ev Exo). Moreover, both in vitro and in vivo results demonstrated that E7 Exo dramatically enhanced EMT of NSCLC cells and promoted the growth of subcutaneous NSCLC xenografts. Additionally, HPV-16 E7 enhanced the expression of EGFR and p-EGFR in both NSCLC cells and exosomes. Furthermore, the inhibition of EGFR activation or exosome secretion suppressed E7 Exo-induced migration, invasion, and EMT of NSCLC. Moreover, 12 kinds of differentially expressed miRNAs between E7 Exo and ev Exo (fold change≥2, P ≤ .05) were screened out, of which 7 miRNAs were up-regulated while 5 miRNAs were down-regulated in A549 E7 Exo. Taken together, our findings suggest that exosomal EGFR is involved in HPV-16 E7-induced EMT of NSCLC cells, which may play a key role in the progression of HPV-related NSCLC.

Circular RNA circZCCHC6 contributes to tumorigenesis by regulating LPCAT1 via miR-433-3p in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-associated mortality worldwide. Circular RNA (circRNA) circZCCHC6 has been reported to be upregulated in the plasma from NSCLC patients. This study is designed to explore the role and mechanism of circZCCHC6 in NSCLC. CircZCCHC6, microRNA-433-3p (miR-433-3p), and lysophosphatidylcholine acyltransferase 1 (LPCAT1) level were determined by real-time quantitative polymerase chain reaction. Cell viability, cell cycle progression, migration, and invasion were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), flow cytometry, wound healing, and transwell assays, severally. The binding relationship between miR-433-3p and circZCCHC6 or LPCAT1 was predicted by Circinteractome or Starbase, and then verified by a dual-luciferase reporter, RNA pull-down, or RNA Immunoprecipitation (RIP) assays. Protein levels of LPCAT1, Cyclin D1, E-cadherin, and Vimentin were examined by western blot assay. The biological role of circZCCHC6 on NSCLC tumor growth and epithelial-mesenchymal transition (EMT) was examined by the xenograft tumor model in vivo. CircZCCHC6 was highly expressed in NSCLC serum, tissues, and cells. Moreover, circZCCHC6 knockdown could repress cell viability, cell cycle progression, migration, invasion, and EMT in NSCLC cells in vitro. The mechanical analysis suggested that circZCCHC6 acted as a sponge of miR-433-3p to regulate LPCAT1 expression. CircZCCHC6 silencing hindered cell growth and EMT of NSCLC in vivo. CircZCCHC6 inhibited the progression of NSCLC cells partly by regulating the miR-433-3p/LPCAT1 axis, implying a promising therapeutic target for the NSCLC treatment.

Repressing phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit gamma by microRNA-142-3p restrains the progression of hepatocellular carcinoma

This paper probes the mechanisms underlying miR-142-3p's modulation of hepatocellular carcinoma (HCC) invasion and apoptosis. Quantitative real-time PCR and Western blot monitored the miR-142-3p profile in HCC tissues and non-tumor tissues. The correlation between miR-142-3p expression and HCC patients' clinicopathological indicators was analyzed. miR-142-3p overexpression and knockdown models were established in HCC cell lines. Cell proliferation was gauged by the colony formation assay and BrdU staining. For measuring apoptosis, flow cytometry and Western blot were implemented. Transwell assay tested cell migration and invasion. miR-142-3p mimics or inhibitors were transfected in Huh7 and HCCLM3 cells. The targeting association between miR-142-3p and PIK3CG was predicted through bioinformatics and further verified by related experiments. The influence of PIK3CG overexpression on miR-142-3p's role in HCC was assayed. A xenografted tumor model was built in mice to validate miR-142-3p knockdown's influence on HCC in vivo. As a result, miR-142-3p exhibited a decreased profile in HCC tissues and cells. Overexpressing miR-142-3p accelerated apoptosis and suppressed the PI3K/AKT/HIF-1α signal. Knocking down miR-142-3p presented opposite effects. PIK3CG overexpression dampened the anti-tumor effect of miR-142-3p. miR-142-3p repressed HCC invasion and intensified apoptosis to restrain HCC by abating the PIK3CG-mediated PI3K/AKT/HIF-1α pathway.

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.

Investigation of the Epithelial to Mesenchymal Transition (EMT) Process in Equine Papillomavirus-2 (EcPV-2)-Positive Penile Squamous Cell Carcinomas

Equine penile squamous cell carcinoma (epSCC) is the most frequent tumor of the external male genitalia, representing 67.5% of equine genital cancers. epSCC is associated with papilloma virus (PV) infection and has been recently proposed as a model for human PV-induced squamous cell carcinomas. It has already been suggested that epSCC might undergo epithelial-to-mesenchymal transition (EMT). This work aims to investigate in detail this process and the possible role of PV oncoproteins in epSCC. For this purpose, 18 penile SCCs were retrospectively selected and tested for both EcPV2 presence and oncoproteins (EcPV2 E6 and EcPV2 E7) expression. Moreover, immunohistochemical EMT characterization was carried out by analyzing the main epithelial markers (E-cadherin, β-catenin, and pan-cytokeratin AE3/AE1), the main mesenchymal markers (N-cadherin and vimentin), and the main EMT-related transcription factors (TWIST-1, ZEB-1). PCR analysis was positive for EcPV2 in 16 out of 18 samples. EMT was investigated in epSCC positive for EcPV2. The immunohistochemistry results suggested the presence of EMT processes in the neoplastic cells at the tumor invasive front. Moreover, the significant upregulation of RANKL, together with BCATN1, LEF1, and FOSL1 genes, might suggest a canonical Wnt pathway activation, similarly to what is reported in human penile squamous cell carcinomas

[Chuanxiong Rhizoma inhibits brain metastasis of lung cancer through multiple active ingredients acting on multiple targets, pathways and biological functions]

OBJECTIVE

To explore the molecular mechanism mediating the inhibitory effect of Chuanxiong Rhizoma against brain metastasis of lung cancer using network pharmacology methods and molecular docking.

METHODS

The chemical components of Chuanxiong Rhizoma and their targets were obtained through the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. The relevant targets for brain metastasis of lung cancer were screened using the GeneCards database. Clusterpro-filerR package was used to perform GO and KEGG enrichment analysis. Cytoscape and STRING database were used to construct the "active ingredient-target-disease" network and protein-protein interaction (PPI) network of Chuanxiong Rhizoma. The core components of Chuanxiong Rhizoma and their targets in the treatment of lung cancer brain metastasis were screened based on the topological parameters, and the results were verified using molecular docking and in Chuanxiong extract- treated human lung cancer PC9 cells by detecting the core target with Western blotting.

RESULTS

Forty-eight active ingredients of Chuanxiong Rhizoma including (Z)-ligustilide, butylphthalide, oleic acid, and myricetone were screened, which target 49 proteins including INS, BDNF, FOS, VEGFA, PTGS2, ESR1, MAPK14, and PTGS1. These proteins participated in 57 biological functions such as nuclear receptor activity, ligand activation, and transcription factor activity, involving 40 signaling pathways such as prolactin signaling pathway, breast cancer, and etrogen signaling. The results of molecular docking showed that myricetone, butylphthalide, 4-hydroxy-3 butylphthalide, (Z)-ligustilide, and ligustalide-E, among others, had strong affinities to 7 cores targets including BDNF, FOS, PTGS2, and MAPK14. In PC9 cells, treatment with Chuanxiong Rhizoma extract resulted in significant reductions in the phosphorylation levels of PI3K, Akt and VEGF (P < 0.01).

CONCLUSION

Chuanxiong Rhizoma contains multiple active ingredients against brain metastasis lung cancer, and these ingredients act on multiple targets involving multiple signal pathways and biological functions.

Fibroblast growth factor 11 (FGF11) promotes non-small cell lung cancer (NSCLC) progression by regulating hypoxia signaling pathway

BACKGROUND

Accumulating evidence highlights the critical roles of fibroblast growth factors (FGFs) in regulating the progression of multiple human cancers, including non-small cell lung cancer (NSCLC). In this study, we investigated the role of FGF11 in the progression of NSCLC.

METHODS

Previously published transcriptomic data (GSE75037 and GSE81089) were used to compare FGF11 expression level between NSCLC tumor tissues and adjacent normal tissues. 100 cases of NSCLC tumor tissues and 30 cases of matched adjacent normal tissues were used to validate FGF11 expression at mRNA and protein level by qPCR and immunohistochemistry. Bioinformatics analysis and dual luciferase reporter analysis were performed to confirm the regulatory effect of miR-525-5p on FGF11 expression. CCK-8 assay and transwell migration assay were employed to examine cellular proliferation, migration and invasion. Gene set enrichment analysis (GSEA) was performed to identify the signaling pathway associated with FGF11 expression. Finally, the functional role of FGF11 in NSCLC tumor growth was evaluated by in vivo study.

RESULTS

FGF11 was upregulated in NSCLC tumor tissues and tumor cell lines. High FGF11 expression was associated with a poor prognosis in NSCLC patients. In vitro loss- and gain-of function experiments demonstrated that FGF11 knockdown inhibited, whereas FGF11 overexpression promoted the proliferation, migration and invasion of NSCLC cells. Dual luciferase reporter assay confirmed that FGF11 was downregulated by miR-525-5p, and the effect of FGF11 on cell proliferation, migration and invasion could be interfered by miR-525-5p. GSEA analysis further revealed that FGF11 expression was enriched with genes in hypoxia signaling pathway and the oncogenic function of FGF11 could be suppressed by knocking down HIF-1α in NSCLC cells. Moreover, FGF11 knockdown suppressed NSCLC tumor growth whereas FGF11 overexpression promoted tumor growth in vivo.

CONCLUSIONS

Our study showed that FGF11 functions as an oncogene in tumor NSCLC progression. miR-525-5p seems to negatively regulate FGF11 and the oncogenic role of FGF11 is dependent on the upregulation of HIF-1α. Our study suggests that targeting FGF11 and HIF-1α may serve as novel strategies for the treatment of NSCLC.

Norcycloartocarpin targets Akt and suppresses Akt-dependent survival and epithelial-mesenchymal transition in lung cancer cells

In searching for novel targeted therapeutic agents for lung cancer treatment, norcycloartocarpin from Artocarpus gomezianus was reported in this study to promisingly interacted with Akt and exerted the apoptosis induction and epithelial-to-mesenchymal transition suppression. Selective cytotoxic profile of norcycloartocarpin was evidenced with approximately 2-fold higher IC50 in normal dermal papilla cells (DPCs) compared with human lung cancer A549, H460, H23, and H292 cells. We found that norcycloartocarpin suppressed anchorage-independent growth, cell migration, invasion, filopodia formation, and decreased EMT in a dose-dependent manner at 24 h, which were correlated with reduced protein levels of N-cadherin, Vimentin, Slug, p-FAK, p-Akt, as well as Cdc42. In addition, norcycloartocarpin activated apoptosis caspase cascade associating with restoration of p53, down-regulated Bcl-2 and augmented Bax in A549 and H460 cells. Interestingly, norcycloartocarpin showed potential inhibitory role on protein kinase B (Akt) the up-stream dominant molecule controlling EMT and apoptosis. Computational molecular docking analysis further confirmed that norcycloartocarpin has the best binding affinity of -12.52 kcal/mol with Akt protein at its critical active site. As Akt has recently recognized as an attractive molecular target for therapeutic approaches, these findings support its use as a plant-derived anticancer agent in cancer therapy.

Collection on reports of molecules linked to epithelial-mesenchymal transition in the process of treating metastasizing cancer: a narrative review

Epithelial-mesenchymal transition (EMT) is a morphological process in which epithelial cells transform into mesenchymal cells via a specific procedure. EMT plays an important role in the cancer invasion-metastasis cascade and the current treatment of metastatic cancer, influences the migration, polarity, and adhesion of tumor cells, promotes their migration, invasiveness, anti-apoptotic ability. It contributes to the changes of the tumor microenvironment and suppresses the sensitivity of tumor cells to chemotherapy, causing cancer metastasis and worse, hindering the control and therapy of it. This paper reviews the mechanisms, detection, and treatments of cancer metastasis that have been identified and applied to date, summarizes the EMT-related biological molecules, providing a reference for EMT-targeted research and therapy. As EMT is significant in the progress of tumor metastasis, it is meaningful for the therapy and control of metastatic cancer to understand the mechanism of EMT at the molecular level. We summarized the mechanisms, detection and therapeutic implications of EMT, listed the research progress of molecules like genes, miRNAs, signaling pathways in EMT. We also discussed the prospects of EMT-targeted treatment in cancer metastasis interventions and the challenges the treatment and researches are facing. The summary is conducive to the treatment and further research of EMT and metastatic cancer.

High-risk human papillomavirus and ZEB1 in ocular adnexal sebaceous carcinoma

BACKGROUND

Ocular adnexal (OA) sebaceous carcinoma is an aggressive malignancy. Oncologic drivers of ocular sebaceous carcinoma are incompletely understood.

METHODS

A retrospective search of our pathology archives for OA sebaceous carcinoma identified 18 primary resection specimens. Immunohistochemistry for p16 and ZEB1 and RNA in situ hybridization for high-risk human papillomavirus (HPV) subtypes were performed.

RESULTS

High-risk HPV was demonstrated in 2/11 (18%) cases. p16 overexpression was observed in 10/11 (91%). No association between gender, age at presentation, tumor location, intraepithelial spread, tumor size, and T stage was observed between HPV-driven and nonviral cases. High expression of ZEB1 was observed in the intraepithelial component of 4/14 (28%) cases and in the subepithelial component of 1/13 (7%) cases. ZEB1 overexpression was not associated with HPV status, T stage, or tumor size.

CONCLUSION

As previously described by others, our findings suggest that a subset of OA sebaceous carcinomas may arise via an HPV-dependent pathway. However, unlike high-risk HPV-driven carcinomas of the oropharynx, we did not identify an association between HPV-status and prognostic features. Furthermore, p16 expression was not a useful surrogate marker for HPV-driven disease. ZEB1 overexpression is not associated with HPV in our cohort of ocular sebaceous carcinoma.

Equine Genital Squamous Cell Carcinoma Associated with EcPV2 Infection: RANKL Pathway Correlated to Inflammation and Wnt Signaling Activation

Simple Summary

Equine genital squamous cell carcinomas (egSCCs) associated with papilloma virus (PV) infection have been recently proposed as model for human PV-induced SCC. In both species, PV mucosal infections often induce cervical, oropharyngeal, penile, anal, vaginal, and vulvar cancer. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with equine papillomavirus 2 (EcPV2) infection investigating receptor activator of nuclear factor-kappa B ligand (RANKL), Wnt, and interleukin (IL)17 signaling pathways. RANKL has been recently demonstrated to play a crucial role in several human tumors, associated with a poor prognosis and metastatic spread; novel targeted therapies through RANKL silencing monoclonal antibodies have been undertaken. EcPV2-E6 DNA was checked, and viral presence was confirmed in 91% of cases, whereas oncogene expression was 60.8% for E6 and 34.7% for E2. RANKL, NFKBp50, NFKBp65, IL6, IL17, IL23p19, IL8, IL12p35, IL12p40, BCATN1, FOSL1, and LEF1 gene expression showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the increased expression of several cytokines and the activation of RANKL/RANK, IL17A, and canonical and non-canonical Wnt signaling pathways. These results may be helpful to identify new targets for immunotherapy strategies confirming egSCCs as a model for the human disease.

Abstract

Equine genital squamous cell carcinomas (egSCCs) are among the most common equine tumors after sarcoids, severely impairing animal health and welfare. Equus caballus papillomavirus type 2 (EcPV2) infection is often related to these tumors. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with EcPV2 infection, investigating receptor activator of nuclear factor-kappa B ligand (RANKL) signaling in NF-kB pathway, together with the Wnt and IL17 signaling pathways. We analyzed the innate immune response through gene expression evaluation of key cytokines and transcription factors. Moreover, Ki67 index was assessed with immunohistochemistry. EcPV2-E6 DNA was checked, and viral presence was confirmed in 21 positive out to 23 cases (91%). Oncogene expression was confirmed in 14 cases (60.8%) for E6 and in 8 (34.7%) for E2. RANKL, nuclear factor kappa-light-chain-enhancer of activated B cells (NFKB)-p50, NFKBp65, interleukin (IL)-6, IL17, IL23p19, IL8, IL12p35, IL12p40, β-catenin (BCATN1), FOS like 1 (FOSL1), and lymphoid enhancer binding factor 1 (LEF1) showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the activation of RANKL/RANK and IL17 with the relative downstream pathways, and a positive modulation of inflammatory cytokines genes such as IL6 and IL8. Moreover, the increase of BCATN1, FOSL1, and LEF1 gene expression suggests an activation of both canonical and non-canonical Wnt signaling pathway that could be critical for carcinogenesis and tumor progression.

Human papillomavirus and prostate cancer: The role of viral expressed proteins in the inhibition of anoikis and induction of metastasis

BACKGROUND

The aim of this study is to address the role of HPV in prostate cancer (PCa) development through the inducement of resistance to anoikis.

METHODS

In this case-control study, prostate tissues and blood samples were collected from 116 individuals, including 72 cases with PCa and 44 non-malignant prostate tissue samples as a control group. The expression level of HPV genes (E2, E6, and E7) and cellular genes including anti-apoptotic mediators (Bcl-2 and survivin), tumor suppressor proteins (Rb and p53), and some mediators involved in anoikis resistance and invasiveness (E-cadherin, N-cadherin, Twist, PTPN13 and SLUG) were evaluated.

RESULTS

HPV genome was identified in 36.1% cases and 15.9% control samples, additionally there was found to be a statistic significant association between the presence of HPV and PCa (OR = 1.64, 95% C.I = 0.8-1.8, P-value = 0.023). HPV genotype 16 and 18 were the most prevalent genotype in both in the PCa group and the control group. The expression level of the tumor suppressor proteins (Rb and p53) and anti-apoptotic mediators (Bcl-2 and Survivin) were significantly decreased and increased, respectively, in the HPV-positive specimens compared to the HPV-negative specimens. Furthermore, the mean expression level of N-cadherin, SLUG, and TWIST in the HPV-positive specimens was higher than HPV-negative specimens while the mean expression level of PTPN-13 and E-cadherin genes in the HPV-positive specimens was lower than HPV-negative specimens.

CONCLUSION

Our study suggests that HPV infection may be involved in the development of PCa metastases by modulating anoikis resistance related genes.

Radiation Response of Cervical Cancer Stem Cells Is Associated with Pretreatment Proportion of These Cells and Physical Status of HPV DNA

Radio- and chemoresistance of cancer stem cells (CSCs) is considered as one of the possible causes of adverse results of chemoradiotherapy for various malignancies, including cervical cancer. However, little is known about quantitative changes in the CSC subpopulation in the course of treatment and mechanisms for individual response of CSCs to therapy. The purpose of the study was to evaluate the association of radiation response of cervical CSCs with clinical and morphological parameters of disease and features of human papillomavirus (HPV) infection. The proportion of CD44⁺CD24^low CSCs was determined by flow cytometry in cervical scrapings from 55 patients with squamous cell carcinoma of uterine cervix before treatment and after fractionated irradiation at a total dose of 10 Gy. Real-time PCR assay was used to evaluate molecular parameters of HPV DNA. Post-radiation increase in the CSC proportion was found in 47.3% of patients. Clinical and morphological parameters (stage, status of lymph node involvement, and histological type) were not significantly correlated with radiation changes in the CSC proportion. Single- and multifactor analyses revealed two independent indicators affecting the radiation response of CSCs: initial proportion of CSCs and physical status of HPV DNA (R = 0.86, p = 0.001 for the multiple regression model in the whole).

Cytochalasin H isolated from mangrove-derived endophytic fungus inhibits epithelial-mesenchymal transition and cancer stemness via YAP/TAZ signaling pathway in non-small cell lung cancer cells

Our previous studies have isolated cytochalasin H (CyH) from endophytic fungus derived from mangrove and found that CyH induced apoptosis and inhibited migration and angiogenesis in non-small cell lung cancer (NSCLC) cells. In this study, we further investigated the effect of CyH on epithelial-mesenchymal transition (EMT) and cancer stemness of A549 and NCI-H460 NSCLC cells and the underlying mechanisms, especially the role of YAP/ TAZ signaling pathway in the process. Our results showed that CyH significantly inhibited invasive ability and the sphere formation of NSCLC cells. The expression of E-cadherin, an EMT epithelial marker, was obviously up-regulated, while the expression of Vimentin and N-cadherin, the EMT mesenchymal markers, was dramatically down-regulated by CyH treatment in NSCLC cells. Moreover, the expression of EMT-associated transcription factors including Slug, Twist1, and Snail1 and stemness markers including Nanog, Sox-2, and Oct-4 was significantly down-regulated by CyH treatment in NSCLC cells. Additionally, CyH significantly down-regulated YAP and TAZ expression and up-regulated LAST1/2 and MST1/2 expression, and CyH inhibited the interaction between YAP and TEAD. Furthermore, YAP knockdown abolished the effect of CyH on the expression of EMT- and stemness-related markers in NSCLC cells. Taken together, these results suggest that CyH inhibits EMT and cancer stemness of NSCLC cells via the regulation of YAP/TAZ signaling pathway.

Huaier shows anti-cancer activities by inhibition of cell growth, migration and energy metabolism in lung cancer through PI3K/AKT/HIF-1α pathway

Huaier has been verified to have anti-cancer effects on many tumours. However, little information is available about the effects of Huaier on non-small cell lung cancer (NSCLC). We sought to probe the anti-cancer effects and related mechanisms of Huaier on lung cancer. A549 cells were pre-treated with 2, 4 and 8 mg/mL Huaier at different time points. Thereafter, cell viability was analysed by CCK-8 and the migration and invasion were detected by Scratch test and Transwell chamber migration assay. Moreover, ELISA, Western blot, shRNA transfection and RT-PCR were conducted to discover the related gene and protein expressions of energy metabolism and phosphatidylinositol 3-kinase (PI3K)/AKT/hypoxia-inducible factor 1α (HIF-1α) pathway. Furthermore, tumour xenografts were accomplished to inspect the anti-cancer effects of Huaier. Our consequences suggested that Huaier considerably repressed cell viability and migration in a dose-dependent way. In addition, Huaier statistically suppressed glycolysis, glucose transport and lactic acid (LA) accumulation. Besides, we detected that Huaier could inactivate the PI3K/AKT/HIF-1α pathway. The in vivo data confirmed that Huaier obviously decreased tumour volume and tumour growth, reduced the glycolysis, glucose transport and HIF-1α expression in the tumour-bearing tissues. Our results suggested Huaier revealed anti-tumour effects in both in vivo and in vitro possibly through PI3K/AKT/HIF-1α pathway.

Epithelial to Mesenchymal Transition (EMT) in a Laryngeal Squamous Cell Carcinoma of a Horse: Future Perspectives

Squamous cell carcinoma (SCC) is one of the most frequent tumors of skin and muco-cutaneous junctions in the horse. Equine papillomavirus type 2 (EcPV2) has been detected in equine SCC of the oral tract and genitals, and recently also in the larynx. As human squamous cell carcinoma of the larynx (SCCL), it is strongly etiologically associated with high-risk papillomavirus (h-HPV) infection. This study focuses on tumor cells behavior in a naturally occurring tumor that can undergo the so-called epithelial to mesenchymal transition (EMT). A SCCL in a horse was investigated by immunohistochemistry using antibodies against E-cadherin, pan-cytokeratin AE3/AE1, β-catenin, N-cadherin, vimentin, ZEB-1, TWIST, and HIF-1α. EcPV2 DNA detection and expression of oncogenes in SCC were investigated. A cadherin switch and an intermediate filaments rearrangement within primary site tumor cells together with the expression of the EMT-related transcription factors TWIST-1, ZEB-1, and HIF-1α were observed. DNA obtained from the tumor showed EcPV2 positivity, with E2 gene disruption and E6 gene dysregulation. The results suggest that equine SCCL might be a valuable model for studying EMT and the potential interactions between EcPV2 oncoproteins and the EMT process in SCCL.

Correlation of Radiation Response of Cervical Cancer Stem Cells with Their Initial Number before Treatment and Molecular Genetic Features of Papillomavirus Infection

The proportion of CD44⁺CD24^low cancer stem cells (CSC) was determined in cervical scrapings of 41 patients with squamous cell carcinoma of the uterine cervix before treatment and after irradiation in a total focal dose of 10 Gy. The relationship of quantitative changes in the CSC population with such parameters of papillomavirus infection as genotype, viral load, and physical status of HPV DNA (the absence or presence of HPV DNA integration into the cell genome and the degree of integration) was studied. Single- and multi-factor analysis revealed 2 independent indicators affecting the radiation response of CSC: initial number of these cells before treatment and physical status of HPV DNA. The increase in the CSC proportion after radiation exposure was observed 4.5-fold more often in patients with an initially low proportion of CSC (<3%) than that in other patients (p=0.001). The CSC proportion increased by on average 3% after irradiation in patients with complete integration of HPV 16/18 DNA and decreased by 3.8 % in patients with partial integration or no integration (p=0.03).

HPV 16 E6/E7 Promote the Glucose Uptake of GLUT1 in Lung Cancer Through Downregulation of TXNIP Due to Inhibition of PTEN Phosphorylation

High-risk human papillomavirus (HPV) infection play an important role in the development of lung cancer. Our previously study showed that E6 and E7 in HPV16 upregulated the expression of GLUT1 in lung cancer cells. However, whether they can promote the glucose uptake by GLUT1 and the underlying molecular mechanism has not been identified. It has been reported that thioredoxin interacting protein (TXNIP) regulates both the expression of GLUT1 and its glucose uptake. We speculate that high risk HPV16 infection may be closely related to TXNIP expression. Therefore, we associate HPV16 with TXNIP to explore the potential molecular mechanism of their regulation of GLUT1 expression and glucose uptake. Using double directional genetic manipulation in lung cancer cells, we showed that HPV16 E6/E7 proteins downregulated the expression of p-PTEN in lung cancer cells, the knockdown of PTEN further inhibited the expression of TXNIP, the inhibition of TXNIP further promoted the accumulation of HIF-1α by inhibiting the translocation of nuclear HIF-1α to the cytoplasm, and subsequently upregulated the expression of GLUT1 at the protein and mRNA levels. More interestingly, we found that the knockdown of TXNIP played a decisive role to promote the glucose uptake by GLUT1. Together, these findings suggested that the PTEN-TXNIP-HIF-1α axis might be related to the E6/E7-mediated expression of GLUT1 and its glucose uptake.

Possible Oncogenic Viruses Associated with Lung Cancer

Lung cancer is the most common cause of cancer death worldwide. Tobacco smoking is the most predominant etiology for lung cancer. However, only a small percentage of heavy smokers develop lung cancer, which suggests that other cofactors are required for lung carcinogenesis. Viruses have been central to modern cancer research and provide profound insights into cancer causes. Nevertheless, the role of virus in lung cancer is still unclear. In this article, we reviewed the possible oncogenic viruses associated with lung cancer.

Human papillomavirus 16 (HPV 16) E6 but not E7 inhibits the antitumor activity of LKB1 in lung cancer cells by downregulating the expression of KIF7

BACKGROUND

The E6 and E7 proteins in human papillomavirus 16 (HPV 16) are the main oncogenes in the occurrence of lung cancer. In recent studies, we found that E6 and E7 downregulated the expression of LKB1 in lung cancer cells. However, it is still unclear how E6 and E7 regulate LKB1 in lung cancer cells.

METHODS

Double directional genetic manipulation and nuclear plasma separation technology were performed to explore the molecular mechanism of E6 and E7 inhibiting the antitumor activity of LKB1 in well-established lung cancer cell lines.

RESULTS

E6 but not E7 significantly downregulated the expression of tumor suppressor KIF7 at protein level, and the inhibition of KIF7 further reduced the expression of LKB1 both in the nuclei and in the cytoplasm, whereas reduced the expression of p-LKB1 in the cytoplasm only. This suggested that HPV 16 E6 but not E7 downregulates the antitumor activity of LKB1 by downregulating the expression of p-LKB1 in the cytoplasm only.

CONCLUSIONS

Here, we demonstrated for the first time that E6 but not E7 inhibits the antitumor activity of LKB1 in lung cancer cells by downregulating the expression of KIF7. Our findings provide new evidence to support the important role of KIF7 in the pathogenesis of lung cancer and suggests new therapeutic targets.

The role of monoamine oxidase A in HPV-16 E7-induced epithelial-mesenchymal transition and HIF-1α protein accumulation in non-small cell lung cancer cells

Our previous studies have found that human papillomavirus (HPV)-16 E7 oncoprotein promotes epithelial-mesenchymal transition (EMT) and hypoxia-inducible factor-1α (HIF-1α) protein accumulation in non-small cell lung cancer (NSCLC) cells and monoamine oxidase A (MAOA) is highly expressed in NSCLC tissues. Here, we further explored the role of MAOA in HPV-16 E7-induced EMT and HIF-1α protein accumulation in A549 and NCI-H460 NSCLC cells. Our results showed that HPV-16 E7 enhanced MAOA expression in NSCLC cells. Additionally, MAOA knockout inhibited HPV-16 E7-induced migration, invasion, and EMT, and significantly reduced HPV-16 E7-induced ROS generation and HIF-1α protein accumulation via promoting its degradation. Furthermore, MAOA knockout suppressed HPV-16 E7-induced ERK1/2 activation. In vivo, MAOA knockout inhibited tumor growth, metastasis, and the expression of EMT-related markers and HIF-1α proteins induced by HPV-16 E7 in NCI-H460 NSCLC subcutaneous xenograft and in situ intrapulmonary models of nude mice. Taken together, our findings provide evidence that MAOA plays a key role in EMT and HIF-1α protein accumulation induced by HPV-16 E7 in NSCLC cells, suggesting that MAOA may be a potential therapeutic target for HPV-related NSCLC.

Slug Is A Surrogate Marker of Epithelial to Mesenchymal Transition (EMT) in Head and Neck Cancer

Background: Epithelial to mesenchymal transition (EMT) promotes therapy resistance in head and neck cancer (HNC) cells. In this study, EMT was quantified in HNC tumor samples by the cellular co-localization of cytokeratin/vimentin, E-cadherin/β-catenin and by Slug expression. Methods: Tissue samples from HNC patients were stained with antibody pairs against cytokeratin/vimentin and E-cadherin/β-catenin. Epithelial–mesenchymal co-localization was quantified using immunofluorescence multichannel image cytometry. Double positivity was confirmed using confocal microscopy. Slug was semi-quantified by 2 specialists and quantified by bright field image cytometry. Results: Tumor samples of 102 patients were investigated. A loss of E-cadherin positive cells (56.9 ± 2.6% vs. 97.9 ± 1.0%; p < 0.0001) and E-cadherin/β-catenin double positive cells (15.4 ± 5.7% vs. 85.4 ± 1.2%; p < 0.0001) was observed in tumor samples. The percentage of Slug positive cells was increased in tumor samples (12.1 ± 3.6% vs. 3.2 ± 2.6%; p = 0.001). Ordinal Slug scores judged by two specialists closely correlated with percentage of Slug-positive cells (Spearman’s rho = 0.81; p < 0.001). Slug score correlated negatively with the percentage of E-cadherin positive cells (r = 0.4; p = 0.006), the percentage of E-cadherin/β-catenin positive cells (r = 0.5; p = 0.001) and positively with cytokeratin/vimentin positive cells (r = 0.4, p = 0.003). Conclusion: EMT can be assessed in HNC tumor probes by cytokeratin/vimentin co-expression and loss of E-cadherin/β-catenin co-expression. Slug score provides a convenient surrogate marker for EMT.

Downregulation of SEMA4C Inhibit Epithelial-Mesenchymal Transition (EMT) and the Invasion and Metastasis of Cervical Cancer Cells via Inhibiting Transforming Growth Factor-beta 1 (TGF-β1)-Induced Hela cells p38 Mitogen-Activated Protein Kinase (MAPK) Activation

BACKGROUND Epithelial-mesenchymal transition (EMT) plays a key role in promoting invasion and metastasis of tumor cells. SEMA4C can regulate the generation of transforming growth factor-beta 1 (TGF-ß1)-induced EMT in cervical cancer. This study investigated the relationship between the regulation of SEMA4C on TGF-ß1-induced p38 mitogen-activated protein kinase (MAPK) activation and invasion and metastasis of cervical cancer. MATERIAL AND METHODS Hela-shSEMA4C cell line was established and the success of transfection was confirmed with fluorescence intensity. Cell experiments were divided into 2 groups. Group 1 was Hela, Hela-shNC, and Hela-shSEMA4C; and Group 2 was Hela, Hela-shNC, Hela-shSEMA4C, Hela+TGF-ß1, Hela-shNC+TGF-ß1, and Hela-shSEMA4C+TGF-ß1. Group 1 was detected for SEMA4C mRNA expression by real-time polymerase chain reaction (RT-PCR), cell viability by Cell Counting Kit-8 (CCK-8), F-actin fluorescence intensity by immunofluorescence, cell migration by scratch test, and cell invasion by invasion test. Group 2 was analyzed for E-cadherin fluorescence intensity by immunofluorescence, human fibronectin (FN) content by enzyme-linked immunosorbent assay (ELISA), and SEMA4C, E-cadherin and p-p38 expressions by Western blot. RESULTS For Group 1, compared with Hela and Hela-shNC subgroups, the SEMA4C mRNA expression, cell viability, F-actin fluorescence intensity, cell migration and invasion ability in the Hela-shSEMA4C subgroup were significantly decreased (P<0.05). For Group 2, compared with Hela and Hela-shNC subgroups, the E-cadherin expression and fluorescence intensity in the Hela-shSEMA4C subgroup were significantly increased (P<0.01), while the FN content, SEMA4C, and p-p38 MAPK expressions were significantly decreased (P<0.01). Compared with Hela-shNC+TGF-ß1 and Hela+TGF-ß1 subgroups, the E-cadherin expression and fluorescence intensity in the Hela-shSEMA4C+TGF-ß1 subgroup were significantly increased (P<0.01), while the FN content, SEMA4C and p-p38 expressions were significantly decreased (P<0.01). CONCLUSIONS Downregulation of SEMA4C can inhibit EMT and the invasion and metastasis of cervical cancer cells via inhibiting TGF-ß1-induced Hela cells p38 MAPK activation.

The role of contextual signal TGF-β1 inducer of epithelial mesenchymal transition in metastatic lung adenocarcinoma patients with brain metastases: an update on its pathological significance and therapeutic potential

Lung adenocarcinoma (LA) is the most common cause of cancer-related death worldwide. Despite the advances over last decade in new targeted therapies, cancer genetics, diagnostics, staging, and surgical techniques as well as new chemotherapy and radiotherapy protocols, the death rate from LA remains high. The tumour microenvironment is composed of several cytokines, one of which is transforming growth factor β1 (TGF-β1), which modulates and mediates the expression of epithelial-mesenchymal transition (EMT), correlated with invasive growth in LAs, and exhibits its pleiotropic effects through binding to transmembrane receptors TβR-1 (also termed activin receptor-like kinases – ALKs) and TβR-2. Accordingly, there is an urgent need to elucidate the molecular mechanisms associated with the tumoural spreading process and therapeutic resistance of this serious pathology. In this review, we briefly discuss the current role of contextual signal TGF-β1 inducer of epithelial mesenchymal transition in metastatic lung adenocarcinoma patients with brain metastases, and give an overview of our current mechanistic understanding of the TGF-β1-related pathways in brain metastases progression, TGF-β1 pathway inhibitors that could be used for clinical treatment, and examination of models used to study these processes. Finally, we summarise the current progress in the therapeutic approaches targeting TGF-β1.

An effective drug sensitizing agent increases gefitinib treatment by down regulating PI3K/Akt/mTOR pathway and up regulating autophagy in non-small cell lung cancer

Gefitinib is one of commonly used first-line treatment options for patients with positive EGFR mutation in non-small cell lung cancer (NSCLC). However, most patients with gefitinib treatment relapse over time due to the loss of drug sensitivity. Compound Kushen injection (CKI) has been used to treat lung cancer, including EGFR-mutated NSCLC. In this report, we examined the anti-cancer and drug sensitivity increased activities of CKI in gefitinib less sensitive NSCLC cell lines H1650 and H1975. Bioinformatics analysis was applied to uncover gene regulation and molecular mechanisms of CKI. Our results indicated that when associating with gefitinib in a dose-dependent fashion, CKI demonstrated the ability to inhibit the proliferation and to increase the sensitivity to gefitinib treatment in gefitinib less sensitive cell lines. This could be the results of down regulation of the PI3K/Akt/mTOR pathway and up regulation of autophagy, which were identified as the potential primary targets of CKI to increase gefitinib treatment effect.

Cytochalasin H Inhibits Angiogenesis via the Suppression of HIF-1α Protein Accumulation and VEGF Expression through PI3K/AKT/P70S6K and ERK1/2 Signaling Pathways in Non-Small Cell Lung Cancer Cells

Our previous study has demonstrated that cytochalasin H (CyH) isolated from mangrove-derived endophytic fungus induces apoptosis and inhibits migration in A549 non-small cell lung cancer (NSCLC) cells. In this study, we further explored the effect of CyH on angiogenesis in NSCLC cells and the underlying molecular mechanisms. A549 and H460 NSCLC cells were treated with different concentrations of CyH for 24 h. The effects of CyH on NSCLC angiogenesis in vitro and in vivo were investigated. Hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression in xenografted NSCLC of nude mice was analyzed by immunohistochemistry. ELISA was used to analyze the concentration of VEGF in the conditioned media derived from treated and untreated NSCLC cells. Western blot was performed to detect the levels of HIF-1α, p-AKT, p-P70S6K, and p-ERK1/2 proteins, and RT-qPCR was used to determine the levels of HIF-1α and VEGF mRNA in A549 and H460 cells. Our results showed that CyH significantly inhibited angiogenesis in vitro and in vivo, and suppressed the hemoglobin content and HIF-1α and VEGF protein expression in xenografted NSCLC tissues of nude mice. Meanwhile, CyH inhibited the secretion of VEGF protein and the expression of HIF-1α protein in A549 and H460 cells. Moreover, CyH had a significant inhibitory effect on VEGF mRNA expression but had no effect on HIF-1α mRNA expression, and CyH inhibited HIF-1α protein expression by promoting the degradation of HIF-1α protein in A549 and H460 cells. Additionally, CyH dramatically inhibited AKT, P70S6K, and ERK1/2 activation in A549 and H460 cells. Taken together, our results suggest that CyH can inhibit NSCLC angiogenesis by the suppression of HIF-1α protein accumulation and VEGF expression through PI3K/AKT/P70S6K and ERK1/2 signaling pathways.

TRPM2 ion channel promotes gastric cancer migration, invasion and tumor growth through the AKT signaling pathway

Transient Receptor Potential Melastatin-2 (TRPM2) ion channel is emerging as a great therapeutic target in many types of cancer, including gastric cancer - a major health threat of cancer related-death worldwide. Our previous study demonstrated the critical role of TRPM2 in gastric cancer cells bioenergetics and survival; however, its role in gastric cancer metastasis, the major cause of patient death, remains unknown. Here, using molecular and functional assays, we demonstrate that TRPM2 downregulation significantly inhibits the migration and invasion abilities of gastric cancer cells, with a significant reversion in the expression level of metastatic markers. These effects were concomitant with decreased Akt and increased PTEN activities. Finally, TRPM2 silencing resulted in deregulation of metastatic markers and abolished the tumor growth ability of AGS gastric cancer cells in NOD/SCID mice. Taken together, our results provide compelling evidence on the important function of TRPM2 in the modulation of gastric cancer cell invasion likely through controlling the PTEN/Akt pathway.

Structure Identification of ViceninII Extracted from Dendrobium officinale and the Reversal of TGF-β1-Induced Epithelial⁻Mesenchymal Transition in Lung Adenocarcinoma Cells through TGF-β/Smad and PI3K/Akt/mTOR Signaling Pathways

ViceninII is a naturally flavonoid glycoside extracted from Dendrobium officinale, a precious Chinese traditional herb, has been proven to be valuable for cancer treatment. Transforming growth factor-β1 (TGF-β1), promotes the induction of epithelial–mesenchymal transition (EMT), a process involved in the metastasis of cells that leads to enhanced migration and invasion. However, there is no previously evidence that ViceninII has an inhibitory effect on cancer metastasis, specifically on the TGF-β1-induced EMT process in lung adenocarcinoma cells. In this experiment, we used UV, ESIMS, and NMR to identify the structure of ViceninII.A549 and H1299 cells were treated with TGF-β1 in the absence and presence of ViceninII, and subsequent migration and invasion were measured by wound-healing and transwell assays. The protein localization and expressions were detected by immunofluorescence and Western blotting. The results indicated that TGF-β1 induced spindle-shaped changes, increased migration and invasion, and upregulated or downregulated the relative expression of EMT biomarkers. Meanwhile, these alterations were significantly inhibited when co-treated with ViceninII and inhibitors LY294002 and SB431542. In conclusion, ViceninII inhibited TGF-β1-induced EMT via the deactivation of TGF-β/Smad and PI3K/Akt/mTOR signaling pathways.This is the first time that the anti-metastatic effects of ViceninII have been demonstrated, and their molecular mechanisms provided.

The Role of MicroRNAs in the Metastatic Process of High-Risk HPV-Induced Cancers

High-risk human papillomavirus (HPV)-driven cancers represent a major health concern worldwide. Despite the constant effort to develop and promote vaccination against HPVs, there is still a high percentage of non-vaccinated population. Furthermore, secondary prevention programs are not ubiquitous worldwide and not widely followed. Metastatic disease is the cause of the great majority of cancer-associated deaths, making it essential to determine its underlying mechanisms and to identify actionable anti-metastatic targets. Within certain types of cancer (e.g., head and neck), HPV-positive tumors show different dissemination patterns when compared with their HPV-negative counterparts, implicating HPV-related factors in the metastatic process. Among the many groups of biomolecules dysregulated by HPV, microRNAs have recently emerged as key regulators of carcinogenesis, able to control complex processes like cancer metastization. In this review, we present recent data on the role of microRNAs in the metastization of HPV-related cancers and on their possible clinical relevance as biomarkers of metastatic disease and/or as therapeutic targets.