Acquisition of anoikis resistance promotes alterations in the Ras/ERK and PI3K/Akt signaling pathways and matrix remodeling in endothelial cells

Morphological Characterization of Intrafollicular Epithelial Bodies (IFEBs) in Rabbit Peyer's Patches

Follicle-associated epithelium (FAE) covering the lymphoid follicles of Peyer's patches (PPs) plays a central role in mucosal immunity. Here, we investigated FAE-derived intrafollicular epithelial bodies (IFEBs) that apparently detach from the FAE and sink deep into the lymphoid tissue of the PPs. Analysis of rabbit PP FAE was carried out by a variety of microscopy and immunohistochemistry techniques using a panel of specific antibodies to determine the nature of the IFEBs. IFEBs displayed the typical features of the FAE, with cytokeratin (CK)+ epithelial cells and CK+/vimentin+ M-cell-like cells. Serial sections of PP tissues showed that the IFEBs are formations frequently separated by the overlying FAE that maintains its integrity. Further, IFEBs showed the presence of junction-associated molecules like zonulin-1 and desmoplakins. Also, IFEBs apparently disaggregate within the lymphoid tissue, as demonstrated by basement membrane disappearance and the finding of isolated epithelial cells that acquire the features of non-polarized epithelial cells. Segments of the FAE in rabbit PPs can detach, forming IFEBs that migrate inside the lymphoid tissue. Although the biological relevance of the newly described IFEBs remains to be determined, we interpreted these data as showing the highly dynamic nature of the PP-associated FAE.

Unexpected antagonism of deoxynivalenol and enniatins in intestinal toxicity through the Ras/PI3K/AKT signaling pathway

Deoxynivalenol (DON) is a kind of widespread traditional Fusarium mycotoxins in the environment, and its intestinal toxicity has received considerable attention. Recently, the emerging Fusarium mycotoxin enniatins (ENNs) have also been shown to frequently coexist with DON in animal feed and food with large consumption. However, the mechanism of intestinal damage caused by the two mycotoxins co-exposure remains unclear. In this study, Caco-2 cell line was used to investigate the combined toxicity and potential mechanisms of four representative ENNs (ENA, ENA1, ENB, and ENB1) and DON. The results showed that almost all mixed groups showed antagonistic effects, particularly ENB at 1/4 IC50 (CI = 6.488). Co-incubation of ENNs mitigated the levels of signaling molecule levels disrupted by DON, including reactive oxygen species (ROS), calcium mobilization (Ca2+), adenosine triphosphate (ATP). The differentially expressed genes (DEGs) between the mixed and ENB groups were significantly enriched in the Ras/PI3K/Akt signaling pathway, including 28 up-regulated genes and 40 down-regulated genes. Quantitative real-time PCR further confirmed the lower expression of apoptotic gene in the mixed group, thereby reducing the cytotoxic effects caused by DON exposure. This study emphasizes that co-exposure of ENNs and DON reduces cytotoxicity by regulating the Ras/PI3K/Akt signaling pathway. Our results provide the first comprehensive evidence about the antagonistic toxicity of ENNs and DON on Caco-2 cells, and new insights into mechanisms investigated by transcriptomics.

Anoikis in cell fate, physiopathology, and therapeutic interventions

The extracellular matrix (ECM) governs a wide spectrum of cellular fate processes, with a particular emphasis on anoikis, an integrin-dependent form of cell death. Currently, anoikis is defined as an intrinsic apoptosis. In contrast to traditional apoptosis and necroptosis, integrin correlates ECM signaling with intracellular signaling cascades, describing the full process of anoikis. However, anoikis is frequently overlooked in physiological and pathological processes as well as traditional in vitro research models. In this review, we summarized the role of anoikis in physiological and pathological processes, spanning embryonic development, organ development, tissue repair, inflammatory responses, cardiovascular diseases, tumor metastasis, and so on. Similarly, in the realm of stem cell research focused on the functional evolution of cells, anoikis offers a potential solution to various challenges, including in vitro cell culture models, stem cell therapy, cell transplantation, and engineering applications, which are largely based on the regulation of cell fate by anoikis. More importantly, the regulatory mechanisms of anoikis based on molecular processes and ECM signaling will provide new strategies for therapeutic interventions (drug therapy and cell-based therapy) in disease. In summary, this review provides a systematic elaboration of anoikis, thus shedding light on its future research.

Intersecting pathways: The role of hybrid E/M cells and circulating tumor cells in cancer metastasis and drug resistance

Cancer metastasis and therapy resistance are intricately linked with the dynamics of Epithelial-Mesenchymal Transition (EMT) and Circulating Tumor Cells (CTCs). EMT hybrid cells, characterized by a blend of epithelial and mesenchymal traits, have emerged as pivotal in metastasis and demonstrate remarkable plasticity, enabling transitions across cellular states crucial for intravasation, survival in circulation, and extravasation at distal sites. Concurrently, CTCs, which are detached from primary tumors and travel through the bloodstream, are crucial as potential biomarkers for cancer prognosis and therapeutic response. There is a significant interplay between EMT hybrid cells and CTCs, revealing a complex, bidirectional relationship that significantly influences metastatic progression and has a critical role in cancer drug resistance. This resistance is further influenced by the tumor microenvironment, with factors such as tumor-associated macrophages, cancer-associated fibroblasts, and hypoxic conditions driving EMT and contributing to therapeutic resistance. It is important to understand the molecular mechanisms of EMT, characteristics of EMT hybrid cells and CTCs, and their roles in both metastasis and drug resistance. This comprehensive understanding sheds light on the complexities of cancer metastasis and opens avenues for novel diagnostic approaches and targeted therapies and has significant advancements in combating cancer metastasis and overcoming drug resistance.

Anoikis-Related Genes Impact Prognosis and Tumor Microenvironment in Bladder Cancer

Anoikis tolerance is an important biological process of tumor colonization and metastasis outside the primary tumor. Recent research has progressively elucidated the function and underlying mechanisms of anoikis in the metastasis of various solid tumors. Nevertheless, the specific mechanisms of anoikis in bladder cancer and its consequent effects on the tumor immune microenvironment remain ambiguous. In this study, we developed an anoikis score based on five genes (ETV7, NGF, SCD, LAMC1, and CASP6) and categorized subjects into high and low-risk groups using the median score from the TCGA database. Our findings indicate that SCD enhances the proliferation of bladder cancer cells in vitro. Furthermore, integrating the anoikis score with clinicopathological features to construct a prognostic nomogram demonstrated precision in assessing patient outcomes. Immune cell analysis revealed elevated infiltration levels of Treg cells and M2 macrophages in the high anoikis score group, whereas CD8+ T cell levels were reduced. This study highlights the importance of anoikis score in predicting patient prognosis, immune cell infiltration, and drug response, which may provide a treatment modality worth exploring in depth for the study of bladder cancer.

Beyond Death: Unmasking the Intricacies of Apoptosis Escape

Apoptosis, or programmed cell death, maintains tissue homeostasis by eliminating damaged or unnecessary cells. However, cells can evade this process, contributing to conditions such as cancer. Escape mechanisms include anoikis, mitochondrial DNA depletion, cellular FLICE inhibitory protein (c-FLIP), endosomal sorting complexes required for transport (ESCRT), mitotic slippage, anastasis, and blebbishield formation. Anoikis, triggered by cell detachment from the extracellular matrix, is pivotal in cancer research due to its role in cellular survival and metastasis. Mitochondrial DNA depletion, associated with cellular dysfunction and diseases such as breast and prostate cancer, links to apoptosis resistance. The c-FLIP protein family, notably CFLAR, regulates cell death processes as a truncated caspase-8 form. The ESCRT complex aids apoptosis evasion by repairing intracellular damage through increased Ca2+ levels. Antimitotic agents induce mitotic arrest in cancer treatment but can lead to mitotic slippage and tetraploid cell formation. Anastasis allows cells to resist apoptosis induced by various triggers. Blebbishield formation suppresses apoptosis indirectly in cancer stem cells by transforming apoptotic cells into blebbishields. In conclusion, the future of apoptosis research offers exciting possibilities for innovative therapeutic approaches, enhanced diagnostic tools, and a deeper understanding of the complex biological processes that govern cell fate. Collaborative efforts across disciplines, including molecular biology, genetics, immunology, and bioinformatics, will be essential to realize these prospects and improve patient outcomes in diverse disease contexts.

Identification of anoikis-related gene signatures and construction of the prognosis model in prostate cancer

Background

One of the primary reasons for tumor invasion and metastasis is anoikis resistance. Biochemical recurrence (BCR) of prostate cancer (PCa) serves as a harbinger of its distant metastasis. However, the role of anoikis in PCa biochemical recurrence has not been fully elucidated.

Methods

Differential expression analysis was used to identify anoikis-related genes based on the TCGA and GeneCards databases. Prognostic models were constructed utilizing LASSO regression, univariate and multivariate Cox regression analyses. Moreover, Gene Expression Omnibus datasets (GSE70770 and GSE46602) were applied as validation cohorts. Gene Ontology, KEGG and GSVA were utilized to explore biological pathways and molecular mechanisms. Further, immune profiles were assessed using CIBERSORT, ssGSEA, and TIDE, while anti-cancer drugs sensitivity was analyzed by GDSC database. In addition, gene expressions in the model were examined using online databases (Human Protein Atlas and Tumor Immune Single-Cell Hub).

Results

113 differentially expressed anoikis-related genes were found. Four genes (EEF1A2, RET, FOSL1, PCA3) were selected for constructing a prognostic model. Using the findings from the Cox regression analysis, we grouped patients into groups of high and low risk. The high-risk group exhibited a poorer prognosis, with a maximum AUC of 0.897. Moreover, larger percentage of immune infiltration of memory B cells, CD8 Tcells, neutrophils, and M1 macrophages were observed in the high-risk group than those in the low-risk group, whereas the percentage of activated mast cells and dendritic cells in the high-risk group were lower. An increased TIDE score was founded in the high-risk group, suggesting reduced effectiveness of ICI therapy. Additionally, the IC50 results for chemotherapy drugs indicated that the low-risk group was more sensitive to most of the drugs. Finally, the genes EEF1A2, RET, and FOSL1 were expressed in PCa cases based on HPA website. The TISCH database suggested that these four ARGs might contribute to the tumor microenvironment of PCa.

Conclusion

We created a risk model utilizing four ARGs that effectively predicts the risk of BCR in PCa patients. This study lays the groundwork for risk stratification and predicting survival outcomes in PCa patients with BCR.

Deciphering anoikis resistance and identifying prognostic biomarkers in clear cell renal cell carcinoma epithelial cells

This study tackles the persistent prognostic and management challenges of clear cell renal cell carcinoma (ccRCC), despite advancements in multimodal therapies. Focusing on anoikis, a critical form of programmed cell death in tumor progression and metastasis, we investigated its resistance in cancer evolution. Using single-cell RNA sequencing from seven ccRCC patients, we assessed the impact of anoikis-related genes (ARGs) and identified differentially expressed genes (DEGs) in Anoikis-related epithelial subclusters (ARESs). Additionally, six ccRCC RNA microarray datasets from the GEO database were analyzed for robust DEGs. A novel risk prognostic model was developed through LASSO and multivariate Cox regression, validated using BEST, ULCAN, and RT-PCR. The study included functional enrichment, immune infiltration analysis in the tumor microenvironment (TME), and drug sensitivity assessments, leading to a predictive nomogram integrating clinical parameters. Results highlighted dynamic ARG expression patterns and enhanced intercellular interactions in ARESs, with significant KEGG pathway enrichment in MYC + Epithelial subclusters indicating enhanced anoikis resistance. Additionally, all ARESs were identified in the spatial context, and their locational relationships were explored. Three key prognostic genes-TIMP1, PECAM1, and CDKN1A-were identified, with the high-risk group showing greater immune infiltration and anoikis resistance, linked to poorer prognosis. This study offers a novel ccRCC risk signature, providing innovative approaches for patient management, prognosis, and personalized treatment.

Redox signaling-mediated tumor extracellular matrix remodeling: pleiotropic regulatory mechanisms

BACKGROUND

The extracellular matrix (ECM), a fundamental constituent of all tissues and organs, is crucial for shaping the tumor microenvironment. Dysregulation of ECM remodeling has been closely linked to tumor initiation and progression, where specific signaling pathways, including redox signaling, play essential roles. Reactive oxygen species (ROS) are risk factors for carcinogenesis whose excess can facilitate the oxidative damage of biomacromolecules, such as DNA and proteins. Emerging evidence suggests that redox effects can aid the modification, stimulation, and degradation of ECM, thus affecting ECM remodeling. These alterations in both the density and components of the ECM subsequently act as critical drivers for tumorigenesis. In this review, we provide an overview of the functions and primary traits of the ECM, and it delves into our current understanding of how redox reactions participate in ECM remodeling during cancer progression. We also discuss the opportunities and challenges presented by clinical strategies targeting redox-controlled ECM remodeling to overcome cancer.

CONCLUSIONS

The redox-mediated ECM remodeling contributes importantly to tumor survival, progression, metastasis, and poor prognosis. A comprehensive investigation of the concrete mechanism of redox-mediated tumor ECM remodeling and the combination usage of redox-targeted drugs with existing treatment means may reveal new therapeutic strategy for future antitumor therapies.

Single nucleotide polymorphisms and Zn transport by ZIP11 shape functional phenotypes of HeLa cells

Zinc (Zn) is a vital micronutrient with essential roles in biological processes like enzyme function, gene expression, and cell signaling. Disruptions in the cellular regulation of Zn2+ ions often lead to pathological states. Mammalian Zn transporters, such as ZIP11, play a key role in homeostasis of this ion. ZIP11 resides predominately in the nucleus and Golgi apparatus. Our laboratory reported a function of ZIP11 in maintaining nuclear Zn levels in HeLa cervical cancer cells. Analyses of cervical and ovarian cancer patients' datasets identified four coding, single nucleotide polymorphisms (SNPs) in SLC39A11, the gene that encodes ZIP11, correlating with disease severity. We hypothesized that these SNPs might translate to functional changes in the ZIP11 protein by modifying access to substrate availability. We also proposed that a metal-binding site (MBS) in ZIP11 is crucial for transmembrane Zn2+ transport and required for maintenance of various pathogenic phenotypes observed in HeLa cells. Here, we investigated these claims by re-introducing single the SLC39A11 gene encoding for mutant residues associated with the SNPs, as well as MBS mutations into HeLa cells knocked down for the transporter. Some SNPs-encoding ZIP11 variants rescued Zn levels, proliferation, migration, and invasiveness of knockdown (KD) cells. Conversely, single MBS mutations mimicked the traits of KD cells, confirming the transporter's role in establishing and maintaining proliferative, migratory, and invasive traits. Overall, the intricate role of Zn in cellular dynamics and cancer progression underscores the significance of Zn transporters like ZIP11 in potential therapeutic interventions.

Is cancer an intelligent species?

Some relevant emerging properties of intelligent systems are "adaptation to a changing environment," "reaction to unexpected situations," "capacity of problem solving," and "ability to communicate." Single cells have remarkable abilities to adapt, make adequate context-dependent decision, take constructive actions, and communicate, thus theoretically meeting all the above-mentioned requirements. From a biological point of view, cancer can be viewed as an invasive species, composed of cells that move from primary to distant sites, being continuously exposed to changes in the environmental conditions. Blood represents the first hostile habitat that a cancer cell encounters once detached from the primary site, so that cancer cells must rapidly carry out multiple adaptation strategies to survive. The aim of this review was to deepen the adaptation mechanisms of cancer cells in the blood microenvironment, particularly referring to four adaptation strategies typical of animal species (phenotypic adaptation, metabolic adaptation, niche adaptation, and collective adaptation), which together define the broad concept of biological intelligence. We provided evidence that the required adaptations (either structural, metabolic, and related to metastatic niche formation) and "social" behavior are useful principles allowing putting into a coherent frame many features of circulating cancer cells. This interpretative frame is described by the comparison with analog behavioral traits typical of various animal models.

Crosstalk between Endothelial Cells and Tumor Cells: A New Era in Prostate Cancer Progression

Prostate cancer stands as one of the most prevalent malignancies afflicting men worldwide. The tumor microenvironment plays a pivotal role in tumor progression, comprising various cell types including endothelial cells, tumor-associated fibroblasts, and macrophages. Recent accumulating evidence underscores the indispensable contribution of endothelial cells to prostate cancer development. Both endothelial cells and tumor cells release a multitude of factors that instigate angiogenesis, metastasis, and even drug resistance in prostate cancer. These factors serve as regulators within the tumor microenvironment and represent potential therapeutic targets for managing prostate cancer. In this review, we provide an overview of the crucial functions of endothelial cells in angiogenesis, metastasis, and drug resistance, and their prospective therapeutic applications in combating this disease.

Uremic Toxin-Induced Exosome-like Extracellular Vesicles Contain Enhanced Levels of Sulfated Glycosaminoglycans which Facilitate the Interaction with Very Small Superparamagnetic Iron Oxide Particles

Uremic toxins exert pathophysiological effects on cells and tissues, such as the generation of a pro-calcifying subtype of exosome-like extracellular vesicles (EVs) in vascular cells. Little is known about the effects of the toxins on the surface structure of EVs. Thus, we studied the effects of uremic toxins on the abundance of sulfated glycosaminoglycans (GAGs) in EVs, and the implications for binding of ligands such as very small superparamagnetic iron oxide particles (VSOPs) which could be of relevance for radiological EV-imaging. Vascular cells were treated with the uremic toxins NaH2PO4 and a mixture of urea and indoxyl sulfate. Uremia in rats was induced by adenine feeding. EVs were isolated from culture supernatants and plasma of rats. By proton T1-relaxometry, magnetic particle spectroscopy, and analysis of genes, proteins, and GAG-contents, we analyzed the roles of GAGs in the ligand binding of EVs. By influencing GAG-associated genes in host cells, uremic toxins induced higher GAG contents in EVs, particularly of sulfated chondroitin sulfate and heparan sulfate chains. EVs with high GAG content interacted stronger with VSOPs compared to control ones. This was confirmed by experiments with GAG-depleted EVs from genetically modified CHO cells and with uremic rat-derived EVs. Mechanistically, uremic toxin-induced PI3K/AKT-signaling and expression of the sulfate transporter SLC26A2 in host cells contributed to high GAG contents in EVs. In conclusion, uremic conditions induce enhanced GAG contents in EVs, which entails a stronger interaction with VSOPs. VSOPs might be suitable for radiological imaging of EVs rich in GAGs.

BLM promotes malignancy in PCa by inducing KRAS expression and RhoA suppression via its interaction with HDGF and activation of MAPK/ERK pathway

Prostate cancer (PCa) has long been the leading cause of cancer-associated deaths among male worldwide. Our previous studies have shown that Bloom syndrome protein (BLM) plays a vital role in PCa proliferation, yet the underlying molecular mechanism remains largely obscure. Mechanistically, BLM directly interacted with hepatoma-derived growth factor (HDGF). Functionally, BLM and HDGF knockdown resulted in the higher impairment of PC3 proliferation, clonogenicity, migration and invasion than that their counterpart with either BLM or HDGF knockdown exclusively. Of note, HDGF overexpression expedited, whereas its knockdown suppressed, PC3 proliferation, clonogenicity, migration and invasion. Additionally, the potentiation or attenuation was partially antagonized upon BLM depletion or overexpression. In line with the vitro data, the impact of BLM and HDGF on tumor growth was investigated in mouse xenograft models. ChIP-seq, dual-luciferase reporter and western blotting assays were employed to expound the regulatory network in PC3 cells. The results unveiled that HDGF activated KRAS and suppressed RhoA transcription, and that the function of HDGF was mediated, in part, by interaction with BLM. Accordingly, the MAPK/ERK pathway was activated. Moreover, the regulation of HDGF on KRAS and RhoA had a signal crosstalk. To recapitulate, BLM and HDGF may serve as novel prognostic markers and potential therapeutic targets in PCa.

MCL1 Inhibition Overcomes the Aggressiveness Features of Triple-Negative Breast Cancer MDA-MB-231 Cells

Triple-Negative Breast Cancer (TNBC) is a particularly aggressive subtype among breast cancers (BCs), characterized by anoikis resistance, high invasiveness, and metastatic potential as well as Epithelial-Mesenchymal Transition (EMT) and stemness features. In the last few years, our research focused on the function of MCL1, an antiapoptotic protein frequently deregulated in TNBC. Here, we demonstrate that MCL1 inhibition by A-1210477, a specific BH3-mimetic, promotes anoikis/apoptosis in the MDA-MB-231 cell line, as shown via an increase in proapoptotic markers and caspase activation. Our evidence also shows A-1210477 effects on Focal Adhesions (FAs) impairing the integrin trim and survival signaling pathways, such as FAK, AKT, ERK, NF-κB, and GSK3β-inducing anoikis, thus suggesting a putative role of MCL1 in regulation of FA dynamics. Interestingly, in accordance with these results, we observed a reduction in migratory and invasiveness capabilities as confirmed by a decrease in metalloproteinases (MMPs) levels following A-1210477 treatment. Moreover, MCL1 inhibition promotes a reduction in EMT characteristics as demonstrated by the downregulation of Vimentin, MUC1, DNMT1, and a surprising re-expression of E-Cadherin, suggesting a possible mesenchymal-like phenotype reversion. In addition, we also observed the downregulation of stemness makers such as OCT3/4, SOX2, NANOG, as well as CD133, EpCAM, and CD49f. Our findings support the idea that MCL1 inhibition in MDA-MB-231 could be crucial to reduce anoikis resistance, aggressiveness, and metastatic potential and to minimize EMT and stemness features that distinguish TNBC.

DUSP6 is a memory retention feedback regulator of ERK signaling for cellular resilience of human pluripotent stem cells in response to dissociation

Cultured human pluripotent stem cells (hPSCs) grow as colonies that require breakdown into small clumps for further propagation. Although cell death mechanism by single-cell dissociation of hPSCs has been well defined, how hPSCs respond to the deadly stimulus and recover the original status remains unclear. Here we show that dissociation of hPSCs immediately activates ERK, which subsequently activates RSK and induces DUSP6, an ERK-specific phosphatase. Although the activation is transient, DUSP6 expression persists days after passaging. DUSP6 depletion using the CRISPR/Cas9 system reveals that DUSP6 suppresses the ERK activity over the long term. Elevated ERK activity by DUSP6 depletion increases both viability of hPSCs after single-cell dissociation and differentiation propensity towards mesoderm and endoderm lineages. These findings provide new insights into how hPSCs respond to dissociation in order to maintain pluripotency.

Understanding and targeting anoikis in metastasis for cancer therapies

The development of effective treatments for cancers requires investigations for a more detailed and comprehensive understanding of the basic cellular mechanisms involved in carcinogenesis, cancer progression, and metastasis. One of those driving mechanisms is anoikis, a special type of apoptosis, which is induced by losing anchorage from the extracellular matrix (ECM). In other words, resisting death in detached cells (cells without ECM) forms an anoikis-resistant phenotype. Since the anoikis-resistance state compensates for the initial steps of cancer metastasis, this review aimed to discuss mechanisms of gaining anoikis/anoikis resistance phenotype in tumor cells. Finally, we highlighted the significance of anoikis in malignancies so as to provide clear insight into cancer diagnosis and therapy development.

A novel risk model based on anoikis: Predicting prognosis and immune infiltration in cutaneous melanoma

Cutaneous melanoma (CM) is a highly aggressive malignancy with a dimal prognosis and limited treatment options. Anoikis is believed to involve in the regeneration, migration, and metastasis of tumor. The exact role of anoikis-related genes (ARGs) in the development and progression of cutaneous melanoma, however, remains elusive. Four ARGs (SNAI2, TFDP1, IKBKG, and MCL1) with significant differential expression were selected through Cox regression and LASSO analyses. Data for internal and external cohorts validated the accuracy and clinical utility of the prognostic risk model based on ARGs. The Kaplan-Meier curve indicated a much better overall survival rate of low-risk patients. Notably, we also found that the action of ARGs in the CM was mediated by immune-related signaling pathways. Consensus clustering and TIME landscape analysis also indicated that the low-risk score patients have excellent immune status. Moreover, the results of immunotherapy response and drug sensitivity also confirmed the potential implications of informing individualized immune therapeutic strategies for CM. Collectively, the predictive risk model constructed based on ARGs provides an excellent and accurate prediction tool for CM patients. This present research provides a rationale for the joint application of targeted therapy and immunotherapy in CM treatment. The approach could have great therapeutic value and make a contribution to personalized medicine therapy.

Roles of anoikis in colorectal cancer therapy and the assessment of anoikis-regulatory molecules as therapeutic targets

Colorectal cancer (CRC) is a deadly malignancy and therapeutic approaches for CRC are evolving every day. Anoikis is a key mechanism for programmed cell death of cancer cells that undergo anchorage-independent growth at a different matrix than the one which is expected. Yet, anoikis is a less studied mechanism of cell death in comparison to other mechanisms such as apoptosis. Relating to this, resistance to anoikis among cancer cells remains critical for improved metastasis and survival in a new environment evading anoikis. Since CRC cells have the ability to metastasize from proximal sites to secondary organs such as liver and promote cancer in those distant sites, a clear knowledge of the mechanisms essential for anchorage-independent growth and subsequent metastasis is necessary to counteract CRC progression and spread. Therefore, the identification of novel drug candidates and studying the roles of anoikis in assisting CRC therapy using such drugs can prevent anchorage-independent cancer cell growth. Additionally, the identification of novel biomarkers or therapeutic targets seems essential for implementing superior therapy, impeding relapse among malignant cells and improving the survival rate of clinical patients. As there are no reviews published on this topic till date, anoikis as a mechanism of cell death and its therapeutic roles in CRC are discussed in this review. In addition, several molecules were identified as therapeutic targets for CRC.

Mechanism of Akt regulation of the expression of collagens and MMPs in conjunctivochalasis

Akt is a central node of many signaling pathways, which plays important roles in cell survival, proliferation, migration, metabolism and collagen synthesis. Conjunctivochalasis (CCH) is one of the most common age-related ocular superficial diseases related to abnormalities in conjunctival extracellular matrix. Here, we studied the role of Akt regulating collagens and MMPs in the pathogenesis of CCH. Primary conjunctival fibroblasts were obtained from CCH patients (n = 13) and age-matched normal controls (n = 10). The levels of Akt, collagen type I, collagen type III, MMP1, and MMP3 were determined by Western blot, qRT-PCR, immunohistochemistry, and immunofluorescence staining. Normal control conjunctival fibroblasts were treated with Akt inhibitor A6730, and CCH fibroblasts were transfected with Akt overexpression vector. The expression of Akt in CCH was significantly lower than that in normal control of conjunctival tissues and cultured fibroblasts. Blocking Akt signaling with Akt inhibitor could inhibit the expression of collagen type I and collagen type III and upregulate the expression of MMP1 and MMP3. Meanwhile, compared with CCH fibroblasts transfected with control mimics, the protein and mRNA expression of collagen type I and collagen type III were increased significantly in Akt overexpression group, while the results of MMP1 and MMP3 in transfected fibroblasts were opposite. Taken together, Akt upregulated the expression of collagen type I and collagen type III and downregulated the expression of MMP1 and MMP3. Akt signaling pathway could provide a direct negative contribution to CCH and might be an attractive target for CCH therapy.

Mitochondria dysfunction in circulating tumor cells

Circulating tumor cells (CTCs) represent a subset of heterogeneous cells, which, once released from a tumor site, have the potential to give rise to metastasis in secondary sites. Recent research focused on the attempt to detect and characterize these rare cells in the circulation, and advancements in defining their molecular profile have been reported in diverse tumor species, with potential implications for clinical applications. Of note, metabolic alterations, involving mitochondria, have been implicated in the metastatic process, as key determinants in the transition of tumor cells to a mesenchymal or stemness-like phenotype, in drug resistance, and in induction of apoptosis. This review aimed to briefly analyse the most recent knowledge relative to mitochondria dysfunction in CTCs, and to envision implications of altered mitochondria in CTCs for a potential utility in clinics.

Confined migration promotes cancer metastasis through resistance to anoikis and increased invasiveness

Mechanical stress is known to fuel several hallmarks of cancer, ranging from genome instability to uncontrolled proliferation or invasion. Cancer cells are constantly challenged by mechanical stresses not only in the primary tumour but also during metastasis. However, this latter has seldom been studied with regards to mechanobiology, in particular resistance to anoikis, a cell death programme triggered by loss of cell adhesion. Here, we show in vitro that migrating breast cancer cells develop resistance to anoikis following their passage through microporous membranes mimicking confined migration (CM), a mechanical constriction that cancer cells encounter during metastasis. This CM-induced resistance was mediated by Inhibitory of Apoptosis Proteins, and sensitivity to anoikis could be restored after their inhibition using second mitochondria-derived activator of caspase (SMAC) mimetics. Anoikis-resistant mechanically stressed cancer cells displayed enhanced cell motility and evasion from natural killer cell-mediated immune surveillance, as well as a marked advantage to form lung metastatic lesions in mice. Our findings reveal that CM increases the metastatic potential of breast cancer cells.

Nitric oxide regulates adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells

Anoikis is a type of apoptosis that occurs in response to the loss of adhesion to the extracellular matrix (ECM). Anoikis resistance is a critical mechanism in cancer and contributes to tumor metastasis. Nitric oxide (NO) is frequently upregulated in the tumor area and is considered an important player in cancer metastasis. The aim of this study was to evaluate the effect of NO on adhesiveness, invasiveness, and migration of anoikis-resistant endothelial cells. Here, we report that anoikis-resistant endothelial cells overexpress endothelial nitric oxide synthase. The inhibition of NO release in anoikis-resistant endothelial cells was able to decrease adhesiveness to fibronectin, laminin, and collagen IV. This was accompanied by an increase in cell invasiveness and migration. Furthermore, anoikis-resistant cell lines displayed a decrease in fibronectin and collagen IV protein expression after L-NAME treatment. These alterations in adhesiveness and invasiveness were the consequence of MMP-2 up-regulation observed after NO release inhibition. The decrease in NO levels was able to down-regulate the activating transcription factor 3 (ATF3) protein expression. ATF3 represses MMP-2 gene expression by antagonizing p53-dependent trans-activation of the MMP-2 promoter. We speculate that the increased release of NO by anoikis-resistant endothelial cells acted as a response to restrict the MMP-2 action, interfering in MMP-2 gene expression via ATF3 regulation. The up-regulation of nitric oxide by anoikis-resistant endothelial cells is an important response to restrict tumorigenic behavior. Without this mechanism, invasiveness and migration potential would be even higher, as shown after L-NAME treatment.

Targeting Oxidative Phosphorylation-Proteasome Activity in Extracellular Detached Cells Promotes Anoikis and Inhibits Metastasis

Metastasis arises owing to tumor cells’ capacity to evade pro-apoptotic signals. Anoikis—the apoptosis of detached cells (from the extracellular matrix (ECM)) is often circumvented by metastatic cells as a result of biochemical and molecular transformations. These facilitate cells’ ability to survive, invade and reattach to secondary sites. Here, we identified deregulated glucose metabolism, oxidative phosphorylation, and proteasome in anchorage-independent cells compared to adherent cells. Metformin an anti-diabetic drug that reduces blood glucose (also known to inhibit mitochondrial Complex I), and proteasome inhibitors were employed to target these changes. Metformin or proteasome inhibitors alone increased misfolded protein accumulation, sensitized tumor cells to anoikis, and impaired pulmonary metastasis in the B16F10 melanoma model. Mechanistically, metformin reduced cellular ATP production, activated AMPK to foster pro-apoptotic unfolded protein response (UPR) through enhanced expression of CHOP in ECM detached cells. Furthermore, AMPK inhibition reduced misfolded protein accumulation, thus highlight relevance of AMPK activation in facilitating metformin-induced stress and UPR cell death. Our findings provide insights into the molecular biology of anoikis resistance and identified metformin and proteasome inhibitors as potential therapeutic options for tumor metastasis.

Anoikis resistance in mammary epithelial cells is mediated by semaphorin 7a

Semaphorin-7a (SEMA7A), best known as a neuroimmune molecule, plays a diverse role in many cellular processes and pathologies. Here, we show that SEMA7A promotes anoikis resistance in cultured mammary epithelial cells through integrins and activation of pro-survival kinase AKT, which led us to investigate a role for SEMA7A during postpartum mammary gland involution-a normal developmental process where cells die by anoikis. Our results reveal that SEMA7A is expressed on live mammary epithelial cells during involution, that SEMA7A expression is primarily observed in α6-integrin expressing cells, and that luminal progenitor cells, specifically, are decreased in mammary glands of SEMA7A-/- mice during involution. We further identify a SEMA7A-α6/β1-integrin dependent mechanism of mammosphere formation and chemoresistance in mammary epithelial cells and suggest that this mechanism is relevant for recurrence in breast cancer patients.

FASN Knockdown Inhibited Anoikis Resistance of Gastric Cancer Cells via P-ERK1/2/Bcl-xL Pathway

Anoikis resistance (AR) is a crucial step in tumor metastasis. The overexpression of fatty acid synthase (FASN) is not only related to the AR of osteosarcoma cells, but also evidenced on gastric cancer (GC). This study investigated the role of FASN in the AR of GC cells. Plates coated with poly-HEMA were used for the culture of cells with AR. Small interfering RNA targeting FASN (siFASN) was transfected into MNK-45 and AGS cells. The number and apoptosis of cells were assessed by a hemacytometer and Annexin-V-FITC/PI assay, respectively. Aggregated cells and colony numbers were manually counted under a microscope. The migration and invasion rates were measured via wound healing and Transwell invasion assays, respectively. The levels of FASN, phosphorylated (p)-ERK1/2, ERK1/2 and Bcl-xL were detected through western blot or quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The results showed that the cell numbers of MNK-45 and AGS were increased while that of GES-1 cell was decreased during the culture in suspension. A higher apoptosis rate and a smaller number of aggregated cells were observed in GES-1 cells in comparison with MNK-45 and AGS cells. A larger colony number, greater migration and invasion rates, and higher mRNA and protein expressions of FASN were presented in the AR group compared with the control group. Cells transfected with siFASN possessed lower migration and invasion rates, reduced expressions of FASN mRNA and protein, p-ERK1/2 and Bcl-xL, and induced a significantly declined ratio of p-ERK1/2 to ERK1/2. These findings suggest that down-regulation of FASN suppresses the AR of GC cells, which may be related to the inhibition of p-ERK1/2/Bcl-xL pathway.

FOXP1 and NDRG1 act differentially as downstream effectors of RAD9-mediated prostate cancer cell functions

Metastatic progression is the key feature of prostate cancer primarily responsible for mortality caused by this disease. RAD9 is an oncogene for prostate cancer, and the encoded protein enhances metastasis-related phenotypes. RAD9 is a transcription factor with a limited set of regulated target genes, but the complete list of downstream genes critical for prostate carcinogenesis is unknown. We used microarray gene expression profiling and chromatin immunoprecipitation in parallel to identify genes transcriptionally controlled by RAD9 that contribute to this cancer. We found expression of 44 genes altered in human prostate cancer DU145 cells when RAD9 is knocked down by siRNA, and all of them bind RAD9 at their genomic location. FOXP1 and NDRG1 were down regulated when RAD9 expression was reduced, and we evaluated them further. We demonstrate that reduced RAD9, FOXP1 or NDGR1 expression decreases cell proliferation, rapid migration, anchorage-independent growth, anoikis resistance, and aerobic glycolysis. Ectopic expression of FOXP1 or NDRG1 partially restored aerobic glycolysis to prostate cancer cells with reduced RAD9 abundance, but only FOXP1 significantly complemented the other deficiencies. We thus show, for the first time, that RAD9 regulates FOXP1 and NDRG1 expression, and they function differently as downstream effectors for RAD9-mediated prostate cancer cell activities.

Comprehensive understanding of anchorage-independent survival and its implication in cancer metastasis

Detachment is the initial and critical step for cancer metastasis. Only the cells that survive from detachment can develop metastases. Following the disruption of cell-extracellular matrix (ECM) interactions, cells are exposed to a totally different chemical and mechanical environment. During which, cells inevitably suffer from multiple stresses, including loss of growth stimuli from ECM, altered mechanical force, cytoskeletal reorganization, reduced nutrient uptake, and increased reactive oxygen species generation. Here we review the impact of these stresses on the anchorage-independent survival and the underlying molecular signaling pathways. Furthermore, its implications in cancer metastasis and treatment are also discussed.

Distinct chemical composition and enzymatic treatment induced human endothelial cells survival in acellular ovine aortae

Objective

The current experiment aimed to assess the impact of detergents such as 3% Triton X-100, 1% peracetic acid, 1% Tween-20, and 1% SDS in combination with Trypsin–EDTA on acellularization of ovine aortae after 7 days.

Results

Hematoxylin–Eosin staining showed an appropriate acellularization rate in ovine aortae, indicated by a lack of cell nuclei in the tunica media layer. DAPI staining confirmed the lack of nuclei in the vascular wall after being exposed to the combination of chemical and enzymatic solutions. Verhoeff-Van Gieson staining showed that elastin fibers were diminished in acellular samples compared to the control group while collagen stands were unchanged. CCK-8 survival assay showed enhanced viability in human umbilical vein endothelial cells 5 days after being cultured on decellularized samples compared to the cells cultured on a plastic surface (p < 0.05). SEM imaging showed flattening of endothelial cells on the acellular surface.

Mechanisms for Modulating Anoikis Resistance in Cancer and the Relevance of Metabolic Reprogramming

The attachment of cells to the extracellular matrix (ECM) is the hallmark of structure–function stability and well-being. ECM detachment in localized tumors precedes abnormal dissemination of tumor cells culminating in metastasis. Programmed cell death (PCD) is activated during tumorigenesis to clear off ECM-detached cells through “anoikis.” However, cancer cells develop several mechanisms for abrogating anoikis, thus promoting their invasiveness and metastasis. Specific factors, such as growth proteins, pH, transcriptional signaling pathways, and oxidative stress, have been reported as drivers of anoikis resistance, thus enhancing cancer proliferation and metastasis. Recent studies highlighted the key contributions of metabolic pathways, enabling the cells to bypass anoikis. Therefore, understanding the mechanisms driving anoikis resistance could help to counteract tumor progression and prevent metastasis. This review elucidates the dynamics employed by cancer cells to impede anoikis, thus promoting proliferation, invasion, and metastasis. In addition, the authors have discussed other metabolic intermediates (especially amino acids and nucleotides) that are less explored, which could be crucial for anoikis resistance and metastasis.

RhoGEF17-An Essential Regulator of Endothelial Cell Death and Growth

The Rho guanine nucleotide exchange factor RhoGEF17 was described to reside in adherens junctions (AJ) in endothelial cells (EC) and to play a critical role in the regulation of cell adhesion and barrier function. The purpose of this study was to analyze signal cascades and processes occurring subsequent to AJ disruption induced by RhoGEF17 knockdown. Primary human and immortalized rat EC were used to demonstrate that an adenoviral-mediated knockdown of RhoGEF17 resulted in cell rounding and an impairment in spheroid formation due to an enhanced proteasomal degradation of AJ components. In contrast, β-catenin degradation was impaired, which resulted in an induction of the β-catenin-target genes cyclin D1 and survivin. RhoGEF17 depletion additionally inhibited cell adhesion and sheet migration. The RhoGEF17 knockdown prevented the cells with impeded cell–cell and cell–matrix contacts from apoptosis, which was in line with a reduction in pro-caspase 3 expression and an increase in Akt phosphorylation. Nevertheless, the cells were not able to proliferate as a cell cycle block occurred. In summary, we demonstrate that a loss of RhoGEF17 disturbs cell–cell and cell–substrate interaction in EC. Moreover, it prevents the EC from cell death and blocks cell proliferation. Non-canonical β-catenin signaling and Akt activation could be identified as a potential mechanism.

Single-cell analysis reveals transcriptomic remodellings in distinct cell types that contribute to human prostate cancer progression

Prostate cancer shows remarkable clinical heterogeneity, which manifests in spatial and clonal genomic diversity. By contrast, the transcriptomic heterogeneity of prostate tumours is poorly understood. Here we have profiled the transcriptomes of 36,424 single cells from 13 prostate tumours and identified the epithelial cells underlying disease aggressiveness. The tumour microenvironment (TME) showed activation of multiple progression-associated transcriptomic programs. Notably, we observed promiscuous KLK3 expression and validated the ability of cancer cells in altering T-cell transcriptomes. Profiling of a primary tumour and two matched lymph nodes provided evidence that KLK3 ectopic expression is associated with micrometastases. Close cell-cell communication exists among cells. We identified an endothelial subset harbouring active communication (activated endothelial cells, aECs) with tumour cells. Together with sequencing of an additional 11 samples, we showed that aECs are enriched in castration-resistant prostate cancer and promote cancer cell invasion. Finally, we created a user-friendly web interface for users to explore the sequenced data.

Altered shear stress on endothelial cells leads to remodeling of extracellular matrix and induction of angiogenesis

Endothelial cells (ECs) are subjected to physical forces such as shear stress (SS) induced by blood flow that leads to significant changes in morphology, physiology and gene expression. The abnormal mechanical forces applied in the cardiovascular system can influence the development of conditions and diseases such as thrombosis, hypertension and atherosclerosis. This study investigated the expression of glycosaminoglycans (GAGs), proteoglycans and extracellular matrix molecules in ECs exposed to normal and altered SS. ECs were exposed to SS of 12 dyn/cm² (artery physiological condition) and 4 dyn/cm² (artery pathological condition). Subsequently, ECs were subjected to immunofluorescence, qPCR, GAG biosynthesis analyses and cell-based assays. SS induced changes in ECs morphology. There were other pathological consequences of altered SS, including inhibited adhesion, stimulation of migration and capillary-like tube formation, as well as increases of GAG synthesis. We observed higher expression of syndecan-4, perlecan, decorin, fibronectin and collagen III α1 and growth factors, including VEGF-A and TGFβ-1. ECs exposed to SS displayed extracellular matrix remodeling as well as expression of cell-matrix and cell-cell interaction molecules. This study contributes to the understanding of how vascular biology is affected by mechanical forces and how these molecules can be affected in cardiovascular diseases.

Effects of syndecan-4 gene silencing by micro RNA interference in anoikis resistant endothelial cells: Syndecan-4 silencing and anoikis resistance

The cell's resistance to cell death by adhesion loss to extracellular matrix (anoikis), contributes to tumor progression and metastasis. Various adhesion molecules are involved in the anoikis resistance, including the syndecan-4 (SDC4), a heparan sulfate proteoglycan (HSPG) present on the cell surface. Changes in the expression of SDC4 have been observed in tumor and transformed cells, indicating its involvement in cancer. In previous works, we demonstrated that acquisition of anoikis resistance resistance by blocking adhesion to the substrate up-regulates syndecan-4 expression in endothelial cells. This study investigates the role of SDC4 in the transformed phenotype of anoikis resistant endothelial cells. Anoikis-resistant endothelial cells (Adh1-EC) were transfected with micro RNA interference (miR RNAi) targeted against syndecan-4. The effect of SDC4 silencing was analyzed by real-time PCR, western blotting and immunofluorescence. Transfection with miRNA-SDC4 resulted in a sequence-specific decrease in syndecan-4 mRNA and protein levels. Furthermore, we observed a reduction in the number of heparan and chondroitin sulfate chains in the cell extract and culture medium. The SDC4 silencing led to downregulation of proliferative and invasive capacity and angiogenic abilities of anoikis-resistant endothelial cells. Compared with the parental cells (Adh1-EC), SDC4 silenced cells (SDC4 miR-Syn-4-1-Adh1-EC e miR-Syn-4-2-Adh1-EC) exhibited an increase in adhesion to collagen and laminin and also in the apoptosis rate. Moreover, transfection with miRNA-SDC4 caused a decrease in the number of cells in the S phase of the cell cycle. This is accompanied by an increase in the heparan sulfate synthesis after 12 h of simulation with fetal calf serum (FCS). SDC4 silencing cells are more dependent of growth factors present in the FCS to synthesize heparan sulfate than parental cells. Similar data were obtained for the wild-type cell line (EC). Our results indicated that downregulation of SDC4 expression reverses the transformed phenotype of anoikis resistant endothelial cells. These and other findings suggest that syndecan-4 is suitable for pharmacological intervention, making it an attractive target for cancer therapy.

Upstream regulators of phosphoinositide 3-kinase and their role in diseases

Phosphoinositide 3-kinase (PI3K), a crucial signaling molecule, is regulated by various upstream regulators. Traditionally, receptor tyrosine kinases and G protein-coupled receptor are regarded as its principle upstream regulators; however, recent reports have indicated that spleen tyrosine kinase, β-arrestin2, Janus kinase, and RAS can also perform this role. Dysregulation of PI3K is common in the progression of various diseases, including, but not limited to, tumors, Alzheimer's disease, Parkinson's disease, rheumatoid arthritis, and acute myelogenous leukemia. The aim of this review is to provide a perspective on PI3K-related diseases examining both the classical and nonclassical upstream regulators of PI3K in detail.

Erlotinib inhibits colon cancer metastasis through inactivation of TrkB-dependent ERK signaling pathway

The distal metastasis is the main cause of death in patients with colon cancer. Tyrosine receptor kinase B (TrkB) and ERK signals may be the potential targets for the treatment of colon cancer metastasis. This study aims to investigate whether erlotinib inhibits distant metastasis of colon cancer by regulating TrkB and ERK signaling pathway. Human colon adenocarcinoma cell lines (SW480 and Caco-2) pretreated with exogenous C-X-C motif chemokine ligand 8 (CXCL8) were used to assess the suppressive effect of erlotinib on tumor metastasis, including anoikis, epithelial-mesenchymal transformation (EMT), migration, and invasion. Through TrkB overexpression, Akt suppression, and ERK suppression, the roles of TrkB, Akt, and ERK in erlotinib-induced metastasis inhibition of colon cancer cells were explored. The results showed that erlotinib alleviated CXCL8-induced metastasis of the colon cancer cells. Overexpression of TrkB in colon cancer cells eliminated the effect of erlotinib on anoikis, inhibition of EMT, migration, and invasion, and downregulation of p-ERK and p-Akt. Furthermore, the inhibition of ERK activation instead of Akt activation was found to participate in erlotinib-mediated metastasis resistance, including anoikis, inhibition of EMT, migration, and invasion. In conclusion, erlotinib inhibits colon cancer cell anoikis resistance, EMT, migration, and invasion by inactivating TrkB-dependent ERK signaling pathway.

Heparan sulfate proteoglycans as trastuzumab targets in anoikis-resistant endothelial cells

Anoikis is a form of programmed cell death induced by loss of contact from neighboring cells or from their extracellular matrix (ECM). Many tumorigenic cells are anoikis resistant, facilitating cancer progression and metastasis. Trastuzumab is a monoclonal antibody used for the treatment of breast and gastric cell cancer, but its mechanism of action is not well elucidated and its target molecules not well defined. Heparan sulfate proteoglycans (HSPGs) and glycosaminoglycans (GAGs) play important roles in tumor development and in response of cancer cells to drugs. This study investigates the effect of trastuzumab on the expression of HSPGs and sulfated glycosaminoglycans (SGAGs) in anoikis-resistant endothelial cells. After trastuzumab treatment, endothelial cells resistant to anoikis show an increase in adhesion to fibronectin followed by a decrease in invasion, proliferation, and angiogenic capacity. In addition, a significant increase in the number of cells in the S phase of the cell cycle was also observed. In relation to HSPGs and SGAGs expression, we observed a decrease in syndecan-4 and perlecan expression, as well as in the heparan sulfate biosynthesis in anoikis-resistant endothelial cells after exposure to trastuzumab. Our results suggest that trastuzumab interacts with GAGs and proteoglycans of the cell surface and ECM and through this interaction controls cellular events in anoikis-resistant endothelial cells.

Shear stress promotes anoikis resistance of cancer cells via caveolin-1-dependent extrinsic and intrinsic apoptotic pathways

Circulating tumor cells (CTCs) need to acquire resistance to anoikis to survive after they experience fluid shear stress in the circulatory and lymphatic systems. However, the mechanism by which tumor cells resist anoikis under shear stress conditions remains unknown. Here, we found that the application of low shear stress (LSS; 2 dyn/cm² ) to human breast carcinoma cells (MDA-MB-231) resulted in increased anoikis resistance when tumor cells were grown under anchorage-independent conditions. Caveolin-1 (Cav-1), the major component of plasma membrane caveolae, was overexpressed in LSS-treated cells and prevented tumor cells from anoikis, while depletion of Cav-1 restored sensitivity to anoikis. LSS-induced dissociation of Cav-1-Fas inhibited formation of the death-inducing signaling complex, caspase-8 activation, and rendered tumor cells resistant to anoikis. Likewise, LSS blocked the mitochondrial pathway through promotion of integrin β1-focal adhesion kinase-mediated multicellular aggregation and suppression of truncated BID translocation mediated crosstalk between the extrinsic and intrinsic apoptotic pathways. Our findings provide insights into the mechanisms by which LSS induces anoikis resistance in breast carcinoma cells through inhibition of Cav-1-dependent extrinsic and intrinsic apoptotic pathways, and serves as a potential therapeutic target for CTCs and metastatic breast cancer.

MiRNA signature predicts the response of patients with advanced lung adenocarcinoma to platinum-based treatment

BACKGROUND

Accumulating literature proved that miRNAs can regulate the sensitivity of platinum and act as a promising candidate to predict the response of patients with lung adenocarcinoma to chemotherapy. However, most studies on miRNAs were restricted to in vitro experiments. This study aimed to evaluate whether miRNAs alone or in combination (miRNA signature) can act as predictive biomarkers of platinum-based chemotherapy in patients with lung adenocarcinoma.

METHODS

Eight miRNAs that most probably predict the efficacy of platinum were screened in 111 tumor tissues of lung adenocarcinoma. Univariate and multivariate Cox analyses, Kaplan-Meier survival curve analysis, Chi-square test, and univariate and multivariate logistic regression analyses were employed to determine whether miRNA expression is associated with the response of patients to platinum-based chemotherapy. The maximum significant odds ratio value was acquired by multiple cycles of multivariate logistic regression analysis. The cut-off points of miRNAs were obtained. A miRNA chemo-sensibility index (CI) formula was established, and its prediction performance was confirmed in another independent set (n = 31).

RESULTS

Underexpression of three miRNAs (miRNA-21, miRNA-125b, and miRNA-224) was independently associated with the chemotherapy sensitivity of patients with lung adenocarcinoma. The miRNA CI formula containing these three miRNAs was calculated as (1.364 × miR-21) + (1.323 × miR-125b) + (1.131 × miR-224). A high CI was related to platinum-based chemotherapy resistance, and its prediction performance was confirmed in the testing set. The MAPK, PI3K-Akt, Ras, and cGMP-PKG signaling pathways were considered to be most probably correlated with platinum resistance.

CONCLUSION

Our miRNA CI formula can act as an independent predictor to predict the response of patients with lung adenocarcinoma to platinum-based chemotherapy.

Phenotype and Functional Features of Human Telomerase Reverse Transcriptase Immortalized Human Airway Smooth Muscle Cells from Asthmatic and Non-Asthmatic Donors

Asthma is an obstructive respiratory disease characterised by chronic inflammation with airway hyperresponsiveness. In asthmatic airways, there is an increase in airway smooth muscle (ASM) cell bulk, which differs from non-asthmatic ASM in characteristics. This study aimed to assess the usefulness of hTERT immortalisation of human ASM cells as a research tool. Specifically we compared proliferative capacity, inflammatory mediator release and extracellular matrix (ECM) production in hTERT immortalised and parent primary ASM cells from asthmatic and non-asthmatic donors. Our studies revealed no significant differences in proliferation, IL-6 and eotaxin-1 production, or CTGF synthesis between donor-matched parent and hTERT immortalised ASM cell lines. However, deposition of ECM proteins fibronectin and fibulin-1 was significantly lower in immortalised ASM cells compared to corresponding primary cells. Notably, previously reported differences in proliferation and inflammatory mediator release between asthmatic and non-asthmatic ASM cells were retained, but excessive ECM protein deposition in asthmatic ASM cells was lost in hTERT ASM cells. This study shows that hTERT immortalised ASM cells mirror primary ASM cells in proliferation and inflammatory profile characteristics. Moreover, we demonstrate both strengths and weaknesses of this immortalised cell model as a representation of primary ASM cells for future asthma pathophysiological research.

PI3K in cancer: its structure, activation modes and role in shaping tumor microenvironment

The role of PI3K in cancer has been well established, and mutations of PIK3CA, the gene coding for catalytic subunit p110α of PI3K, are found in approximately 30% human cancers. The hyperactivated PI3K pathway plays a central role in the tumor cell activities such as proliferation, differentiation, chemotaxis, survival, trafficking and metabolism. Besides, PI3K pathway is involved in the regulation of angiogenesis and the host immune response against cancer. Therefore, the inhibition of PI3K pathway can yield multifaceted tumor cell-extrinsic effects that may synergize with chemotherapy, and more importantly, with the newly revived immunotherapy. Here, we review the structures and activation modes of PI3Ks and its implications in angiogenesis, extracellular matrix remodeling and tumor immunity.