Specific gene expression signatures induced by the multiple oncogenic alterations that occur within the PTEN/PI3K/AKT pathway in lung cancer

Bioinformatics and experimental approach identify lipocalin 2 as a diagnostic and prognostic indicator for lung adenocarcinoma

BACKGROUND

lipocalin 2 (LCN2) is a secreted glycoprotein that plays key roles in tumorigenesis and progression. Interestingly, LCN2 appears to have a contradictory function in developing lung adenocarcinoma (LUAD). Thus, we intend to explore the role of LCN2 in LUAD through bioinformatics and experimental validation.

METHODS

LCN2 expression of LUAD was investigated in the TCGA, TIMER and HPA databases. The relationship between LCN2 and prognosis was investigated by KM plotter, TCGA and GEO databases. GO, KEGG and protein-protein interactions network analysis were conducted to investigate the potential mechanism of LCN2. The relevance of LCN2 to cancer-immune infiltrates was investigated in the TCGA and TIMER databases. Quantitative reverse transcription PCR, western blot and enzyme-linked immunosorbent assay were performed to identify the expression level of LCN2 in cells and serum samples. The CCK-8, wound healing and transwell assay were used to confirm the effect of LCN2 on cell proliferation, migration and invasion in LUAD. The receiver operating characteristic curve was utilized to assess the diagnostic efficiency of LCN2 further.

RESULTS

LCN2 expression was significantly upregulated in LUAD (P < 0.05), and was correlated with the clinical stage, tumor size, lymph node metastasis and distant metastasis (P < 0.05). There was a high correlation between high LCN2 and worse prognosis in LUAD. Functional network analysis suggested that LCN2 was associated with multiple signal pathways in cancers, such as JAK-STAT, TNF, NF-κB, HIF-1 and PI3K-Akt signal pathways. In addition, the knockdown of LCN2 significantly inhibited the ability of cell proliferation, migration and invasion. Immune infiltration analysis indicated that LCN2 is associated with multiple immune cell infiltration. Notably, LCN2 demonstrated high diagnostic efficiency for LUAD (AUC = 0.818, P < 0.05), especially for stage III-IV patients could reach 0.895.

CONCLUSIONS

LCN2 as an oncogenic glycoprotein promotes the cancer progression related to immune infiltrates, which might be a potential diagnostic and prognostic marker in LUAD.

"Oh, Dear We Are in Tribble": An Overview of the Oncogenic Functions of Tribbles 1

Pseudokinases are catalytically inactive proteins in the human genome that lack the ability to transfer phosphate from ATP to their substrates. The Tribbles family of pseudokinases contains three members: Tribbles 1, 2, and 3. Tribbles 1 has recently gained importance because of its involvement in various diseases, including cancer. It acts as a scaffolding protein that brings about the degradation of its substrate proteins, such as C/EBPα/β, MLXIPL, and RAR/RXRα, among others, via the ubiquitin proteasome system. It also serves as an adapter protein, which sequesters different protein molecules and activates their downstream signaling, leading to processes, such as cell survival, cell proliferation, and lipid metabolism. It has been implicated in cancers such as AML, prostate cancer, breast cancer, CRC, HCC, and glioma, where it activates oncogenic signaling pathways such as PI3K-AKT and MAPK and inhibits the anti-tumor function of p53. TRIB1 also causes treatment resistance in cancers such as NSCLC, breast cancer, glioma, and promyelocytic leukemia. All these effects make TRIB1 a potential drug target. However, the lack of a catalytic domain renders TRIB1 "undruggable", but knowledge about its structure, conformational changes during substrate binding, and substrate binding sites provides an opportunity to design small-molecule inhibitors against specific TRIB1 interactions.

Cross-Comparison of Inflammatory Skin Disease Transcriptomics Identifies PTEN as a Pathogenic Disease Classifier in Cutaneous Lupus Erythematosus

Tissue transcriptomics is used to uncover molecular dysregulations underlying diseases. However, the majority of transcriptomics studies focus on single diseases with limited relevance for understanding the molecular relationship between diseases or for identifying disease-specific markers. In this study, we used a normalization approach to compare gene expression across nine inflammatory skin diseases. The normalized datasets were found to retain differential expression signals that allowed unsupervised disease clustering and identification of disease-specific gene signatures. Using the NS-Forest algorithm, we identified a minimal set of biomarkers and validated their use as diagnostic disease classifier. Among them, PTEN was identified as being a specific marker for cutaneous lupus erythematosus and found to be strongly expressed by lesional keratinocytes in association with pathogenic type I IFNs. In fact, PTEN facilitated the expression of IFN-β and IFN-κ in keratinocytes by promoting activation and nuclear translocation of IRF3. Thus, cross-comparison of tissue transcriptomics is a valid strategy to establish a molecular disease classification and to identify pathogenic disease biomarkers.

Secreted PGK1 and IGFBP2 contribute to the bystander effect of miR-10b gene editing in glioma

MicroRNA-10b (miR-10b) is an essential glioma driver and one of the top candidates for targeted therapies for glioblastoma and other cancers. This unique miRNA controls glioma cell cycle and viability via an array of established conventional and unconventional mechanisms. Previously reported CRISPR-Cas9-mediated miR-10b gene editing of glioma cells in vitro and established orthotopic glioblastoma in mouse models demonstrated the efficacy of this approach and its promise for therapy development. However, therapeutic gene editing in patients' brain tumors may be hampered, among other factors, by the imperfect delivery and distribution of targeting vectors. Here, we demonstrate that miR-10b gene editing in glioma cells triggers a potent bystander effect that leads to the selective cell death of the unedited glioma cells without affecting the normal neuroglial cells. The effect is mediated by the secreted miR-10b targets phosphoglycerate kinase 1 (PGK1) and insulin-like growth factor binding protein 2 (IGFBP2) that block cell-cycle progression and induce glioma cell death. These findings further support the feasibility of therapeutic miR-10b editing without the need to target every cell of the tumor.

The Potent G-Quadruplex-Binding Compound QN-302 Downregulates S100P Gene Expression in Cells and in an In Vivo Model of Pancreatic Cancer

The naphthalene diimide compound QN-302, designed to bind to G-quadruplex DNA sequences within the promoter regions of cancer-related genes, has high anti-proliferative activity in pancreatic cancer cell lines and anti-tumor activity in several experimental models for the disease. We show here that QN-302 also causes downregulation of the expression of the S100P gene and the S100P protein in cells and in vivo. This protein is well established as being involved in key proliferation and motility pathways in several human cancers and has been identified as a potential biomarker in pancreatic cancer. The S100P gene contains 60 putative quadruplex-forming sequences, one of which is in the promoter region, 48 nucleotides upstream from the transcription start site. We report biophysical and molecular modeling studies showing that this sequence forms a highly stable G-quadruplex in vitro, which is further stabilized by QN-302. We also report transcriptome analyses showing that S100P expression is highly upregulated in tissues from human pancreatic cancer tumors, compared to normal pancreas material. The extent of upregulation is dependent on the degree of differentiation of tumor cells, with the most poorly differentiated, from more advanced disease, having the highest level of S100P expression. The experimental drug QN-302 is currently in pre-IND development (as of Q1 2023), and its ability to downregulate S100P protein expression supports a role for this protein as a marker of therapeutic response in pancreatic cancer. These results are also consistent with the hypothesis that the S100P promoter G-quadruplex is a potential therapeutic target in pancreatic cancer at the transcriptional level for QN-302.

Discovering Synergistic Compounds with BYL-719 in PI3K Overactivated Basal-like PDXs

Basal-like triple-negative breast cancer (TNBC) tumor cells are difficult to eliminate due to resistance mechanisms that promote survival. While this breast cancer subtype has low PIK3CA mutation rates when compared to estrogen receptor-positive (ER+) breast cancers, most basal-like TNBCs have an overactive PI3K pathway due to gene amplification or high gene expression. BYL-719 is a PIK3CA inhibitor that has been found to have low drug-drug interactions, which increases the likelihood that it could be useful for combinatorial therapy. Alpelisib (BYL-719) with fulvestrant was recently approved for treating ER+ breast cancer patients whose cancer had developed resistance to ER-targeting therapy. In these studies, a set of basal-like patient-derived xenograft (PDX) models was transcriptionally defined with bulk and single-cell RNA-sequencing and clinically actionable mutation profiles defined with Oncomine mutational profiling. This information was overlaid onto therapeutic drug screening results. BYL-719-based, synergistic two-drug combinations were identified with 20 different compounds, including everolimus, afatinib, and dronedarone, which were also found to be effective at minimizing tumor growth. These data support the use of these drug combinations towards cancers with activating PIK3CA mutations/gene amplifications or PTEN deficient/PI3K overactive pathways.

Development and validation of an immune-related gene signature for prognosis in Lung adenocarcinoma

The most common type of lung cancer tissue is lung adenocarcinoma. The TCGA-LUAD cohort retrieved from the TCGA dataset was considered the internal training cohort, while GSE68465 and GSE13213 datasets from the GEO database were used as the external test cohort. The TCGA-LUAD cohort was classified into two immune subtypes using single-sample gene set enrichment analysis of the immune gene set and unsupervised clustering analysis. The ESTIMATE algorithm, the CIBERSORT algorithm, and HLA family expression levels again validated the reliability of this typing. We performed Venn analysis using immune-related genes from the immport dataset and differentially expressed genes from the subtypes to retrieve differentially expressed immune genes (DEIGs). In addition, DEIGs were used to construct a prognostic model with the least absolute shrinkage and selection operator regression analysis. A reliable risk model consisting of 11 DEIGs, including S100P, INHA, SEMA7A, INSL4, CD40LG, AGER, SERPIND1, CD1D, CX3CR1, SFTPD, and CD79A, was then built, and its reliability was further confirmed by ROC curve and calibration plot analysis. The high-risk score subgroup had a poor prognosis and a lower tumour immune dysfunction and exclusion score, indicating a greater likelihood of anti-PD-1/cytotoxic T lymphocyte antigen 4 benefit.

FAM83B promotes the invasion of primary lung adenocarcinoma via PI3K/AKT/NF-κB pathway

OBJECTS

The family with sequence similarity 83B (FAM83B) is one of the markers for poor prognosis in several carcinomas, but the expression and the mechanism resulted in malignant phenotype in lung adenocarcinoma (LUAD) remain to be elucidated.

METHODS

 Data of RNA-seq in LUAD were downloaded from the cancer genome atlas (TCGA) database for differential expression and survival analysis, and immunohistochemistry was employed to analyze the protein expression of FAM83B in 126 cases of primary LUAD. The LUAD cell lines were collected for the detection of the effects on migration and invasion. Then, western blot was performed to measure the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and activation of PI3K/AKT/NF-κB pathway.

RESULTS

FAM83B was overexpressed in multiple types of carcinomas; The differential expression analysis revealed that the level of FAM83B was higher in LUAD than that in para-carcinoma; The patients with overexpression of FAM83B were with shorter overall survival (OS), disease specific survival (DSS) and progress free interval (PFI); Enrichment analysis suggested it was related to the focal adhesion of LUAD. Immunohistochemistry analysis demonstrated that higher FAM83B expression was positively related to lymph node metastasis in primary. Scratch assay and Borden chamber assay showed that the overexpression of FAM83B promoted migration and invasion activity in vitro. Furthermore, high level of FAM83B accelerated the tumorigenesis in vivo. Western blot showed that TIMP-1 was upregulated in H1299/FAM83B OE cells accompanying by the activation of PI3K/AKT/NF-κB pathway.

CONCLUSIONS

FAM83B was a marker for poor prognosis of LUAD and it might promote the expression of TIMP-1 by activating PI3K/AKT/NF-κB pathway and then affect the ECM balance, which resulted in the migration and invasion of LUAD.

Cancer resistance via the downregulation of the tumor suppressors RKIP and PTEN expressions: therapeutic implications

The Raf kinase inhibitor protein (RKIP) has been reported to be underexpressed in many cancers and plays a role in the regulation of tumor cells' survival, proliferation, invasion, and metastasis, hence, a tumor suppressor. RKIP also regulates tumor cell resistance to cytotoxic drugs/cells. Likewise, the tumor suppressor, phosphatase and tensin homolog (PTEN), which inhibits the phosphatidylinositol 3 kinase (PI3K)/AKT pathway, is either mutated, underexpressed, or deleted in many cancers and shares with RKIP its anti-tumor properties and its regulation in resistance. The transcriptional and posttranscriptional regulations of RKIP and PTEN expressions and their roles in resistance were reviewed. The underlying mechanism of the interrelationship between the signaling expressions of RKIP and PTEN in cancer is not clear. Several pathways are regulated by RKIP and PTEN and the transcriptional and post-transcriptional regulations of RKIP and PTEN is significantly altered in cancers. In addition, RKIP and PTEN play a key role in the regulation of tumor cells response to chemotherapy and immunotherapy. In addition, molecular and bioinformatic data revealed crosstalk signaling networks that regulate the expressions of both RKIP and PTEN. These crosstalks involved the mitogen-activated protein kinase (MAPK)/PI3K pathways and the dysregulated nuclear factor-kappaB (NF-κB)/Snail/Yin Yang 1 (YY1)/RKIP/PTEN loop in many cancers. Furthermore, further bioinformatic analyses were performed to investigate the correlations (positive or negative) and the prognostic significance of the expressions of RKIP or PTEN in 31 different human cancers. These analyses were not uniform and only revealed that there was a positive correlation between the expression of RKIP and PTEN only in few cancers. These findings demonstrated the existence of signaling cross-talks between RKIP and PTEN and both regulate resistance. Targeting either RKIP or PTEN (alone or in combination with other therapies) may be sufficient to therapeutically inhibit tumor growth and reverse the tumor resistance to cytotoxic therapies.

Spatial modeling reveals nuclear phosphorylation and subcellular shuttling of YAP upon drug-induced liver injury

The Hippo signaling pathway controls cell proliferation and tissue regeneration via its transcriptional effectors yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). The canonical pathway topology is characterized by sequential phosphorylation of kinases in the cytoplasm that defines the subcellular localization of YAP and TAZ. However, the molecular mechanisms controlling the nuclear/cytoplasmic shuttling dynamics of both factors under physiological and tissue-damaging conditions are poorly understood. By implementing experimental in vitro data, partial differential equation modeling, as well as automated image analysis, we demonstrate that nuclear phosphorylation contributes to differences between YAP and TAZ localization in the nucleus and cytoplasm. Treatment of hepatocyte-derived cells with hepatotoxic acetaminophen (APAP) induces a biphasic protein phosphorylation eventually leading to nuclear protein enrichment of YAP but not TAZ. APAP-dependent regulation of nuclear/cytoplasmic YAP shuttling is not an unspecific cellular response but relies on the sequential induction of reactive oxygen species (ROS), RAC-alpha serine/threonine-protein kinase (AKT, synonym: protein kinase B), as well as elevated nuclear interaction between YAP and AKT. Mouse experiments confirm this sequence of events illustrated by the expression of ROS-, AKT-, and YAP-specific gene signatures upon APAP administration. In summary, our data illustrate the importance of nuclear processes in the regulation of Hippo pathway activity. YAP and TAZ exhibit different shuttling dynamics, which explains distinct cellular responses of both factors under physiological and tissue-damaging conditions.

Epithelial Membrane Protein 1 Promotes Sensitivity to RSL3-Induced Ferroptosis and Intensifies Gefitinib Resistance in Head and Neck Cancer

Epithelial membrane protein (EMP1), a member of the peripheral myelin protein (PMP22) family, is involved in the development of various human malignancies. However, the expression level of EMP1 and its functional role in head and neck squamous cell carcinoma (HNSCC) remain unclear to date. Ferroptosis, a newly characterized form of regulated cell death, plays an essential role in tumorigenesis. In this study, we aimed to investigate the expression levels of EMP1 in HNSCC and normal tissues, as well as to identify the function of EMP1 in regulating ferroptosis during the progression of HNSCC. To further explore the biological function of EMP1 in vitro, transient transfection was used to overexpress EMP1 in the HNSCC cell lines Hep2 and Detroit562. Functionally, our results indicated that EMP1 overexpression could not affect the initiation of ferroptosis directly but reinforced RSL3-induced ferroptosis on HNSCC cells. Furthermore, mechanical study indicated that EMP1 mediated the ferroptosis via cell density-regulated Hippo-TAZ pathway and regulated the expression of Rac1 and NOX1. In addition, our study demonstrated that EMP1 overexpression could promote gefitinib resistance by targeting the MAPK pathway. In summary, our findings indicate that EMP1 may act as an oncogene and serve as a therapeutic target against malignant progression of HNSCC.

QPRT Acts as an Independent Prognostic Factor in Invasive Breast Cancer

Background. Quinolinic acid phosphoribosyltransferase (QPRT) is a rate-limiting enzyme that encodes the uronic acid pathway, which is involved in cell cycle progression and cancer cell metabolism. Some studies have demonstrated the progrowth effect of QPRT on breast cancer (BRCA) tumour cells, but its mechanism of action requires further exploration. Methods. We investigated the expression of QPRT and the prognosis of patients with different tumours by performing a pan-cancer analysis of QPRT. Prognostic values for overall survival (OS) were determined using uni- and multivariate Cox proportional hazard analyses. The prognostic survival of patients with a different pathological staging of BRCA and with QPRT high and low expression was also analysed. We also explored the relevant pathways by which QPRT affected BRCA tumorigenesis by gene set enrichment analysis (GSEA) and western blotting. The impact of QPRT on the PI3K/Akt pathway was also evaluated. Results. Pan-cancer analysis revealed significant QPRT expression in pan-cancer and correlated with prognosis in most tumour patients. QPRT was also highly expressed in BRCA when patients had poor prognoses, and its expression was associated with different pathological BRCA subtypes. GSEA revealed an association between BRCA progression and the cell cycle and the phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway, and this association was confirmed by western blotting. Conclusion. QPRT is highly expressed in breast cancer and particularly in HER2 breast cancer. Upregulated QPRT expression is an independent predictor of breast cancer prognosis and promotes breast cancer progression by activating the PI3K/Akt signalling pathway.

The Pseudokinase TRIB1 in Immune Cells and Associated Disorders

Simple Summary

TRIB1 is at the center of major cell signaling pathways. In this review, we describe its role in immune cells and highlight TRIB1 interacting partners which suggests cell-specific functions and that TRIB1 is involved in cellular homeostasis and also in different cancers and immune-related disorders.

Abstract

Research advances in Tribbles homolog (TRIB) genes have established the consensus that this protein family plays roles in diverse biological conditions and regulates intracellular signaling networks and several human diseases. In this review, we focus on one member of the family, TRIB1, and its role at the crossroads of immune signaling. TRIB1 directly interacts with transcription factors such as FOXP3 and C/EBPα, with several signaling molecules such as MEK1 and MALT1 and directly acts on key cell signaling pathways such as the MAPK and NF-κB pathways. Altogether, these interactions emphasize that TRIB1 is at the center of major cell signaling pathways while TRIB1 has cell-specific roles, potentially depending on the expressing cells and binding partners. In this review, we describe its roles in immune cells and highlight the interacting partners explaining these functions which suggests TRIB1 as a precise mediator of cellular homeostasis as well as in different cancers and immune-related disorders.

Metformin for Cardiovascular Protection, Inflammatory Bowel Disease, Osteoporosis, Periodontitis, Polycystic Ovarian Syndrome, Neurodegeneration, Cancer, Inflammation and Senescence: What Is Next?

Diabetes is accompanied by several complications. Higher prevalence of cancers, cardiovascular diseases, chronic kidney disease (CKD), obesity, osteoporosis, and neurodegenerative diseases has been reported among patients with diabetes. Metformin is the oldest oral antidiabetic drug and can improve coexisting complications of diabetes. Clinical trials and observational studies uncovered that metformin can remarkably prevent or alleviate cardiovascular diseases, obesity, polycystic ovarian syndrome (PCOS), osteoporosis, cancer, periodontitis, neuronal damage and neurodegenerative diseases, inflammation, inflammatory bowel disease (IBD), tuberculosis, and COVID-19. In addition, metformin has been proposed as an antiaging agent. Numerous mechanisms were shown to be involved in the protective effects of metformin. Metformin activates the LKB1/AMPK pathway to interact with several intracellular signaling pathways and molecular mechanisms. The drug modifies the biologic function of NF-κB, PI3K/AKT/mTOR, SIRT1/PGC-1α, NLRP3, ERK, P38 MAPK, Wnt/β-catenin, Nrf2, JNK, and other major molecules in the intracellular signaling network. It also regulates the expression of noncoding RNAs. Thereby, metformin can regulate metabolism, growth, proliferation, inflammation, tumorigenesis, and senescence. Additionally, metformin modulates immune response, autophagy, mitophagy, endoplasmic reticulum (ER) stress, and apoptosis and exerts epigenetic effects. Furthermore, metformin protects against oxidative stress and genomic instability, preserves telomere length, and prevents stem cell exhaustion. In this review, the protective effects of metformin on each disease will be discussed using the results of recent meta-analyses, clinical trials, and observational studies. Thereafter, it will be meticulously explained how metformin reprograms intracellular signaling pathways and alters molecular and cellular interactions to modify the clinical presentations of several diseases.

AKT1E17K -mutated meningioma cell lines respond to treatment with the AKT inhibitor AZD5363

AIMS

Meningiomas are the most frequent primary brain tumours. Recently, knowledge about the molecular drivers underlying aggressive meningiomas has been expanded. A hotspot mutation in the AKT1 gene (AKT1^E17K ), which is found in meningiomas at the convexity and especially at the skull base, has been associated with earlier tumour recurrence.

METHODS

Here, we analysed the effects of the AKT1^E17K mutation and treatment response to the Akt inhibitor AZD5363 in transgenic meningioma cell clones and mouse xenografts modelling convexity or skull base meningiomas.

RESULTS

We show that the AKT^E17K mutation significantly enhances meningioma cell proliferation and colony size in vitro, resulting in significantly shortened survival times of mice carrying convexity or skull base AKT1^E17K xenografts. Treatment of mutant cells or xenografts (150 mg/kg/d) with AZD5363 revealed a significant decrease in cell proliferation and colony size and a prolongation of mouse survival. Western blots revealed activation of AKT1 kinase (phosphorylation at Ser273 and Thr308) by the E17K mutation in human meningioma samples and in our in vitro and in vivo models.

CONCLUSIONS

Our data suggest that AKT1^E17K mutated meningiomas are a promising selective target for AZD5363.

Experimental models of lipid overload and their relevance in understanding skeletal muscle insulin resistance and pathological changes in mitochondrial oxidative capacity

It remains essential to decipher some of the pathological mechanisms that link obesity with deteriorating human health. Insulin resistance, due to enhanced free fatty acid substrate delivery, results in disrupted glucose homeostasis and altered mitochondrial oxidative capacity, which is a characteristic feature of an obese state. In fact, as a major site for regulating glucose homeostasis and energy production in response to insulin, the skeletal muscle has become an interesting target tissue to understand the impact of lipid overload on the development of insulin resistance and impaired mitochondrial respiratory function. In addition to systematically retrieving the discussed data, the current review brings an essential perspective in understanding the relevance of experimental models of lipid overload such as high fat diets in understanding the pathological link between insulin resistance and pathological changes in mitochondrial oxidative capacity. Importantly, inclusion of evidence from transgenic model highlights some of the unique molecular targets that are implicated in the development of insulin resistance and inefficient mitochondrial respiration processes within an obese state. Importantly, saturation with lipid products such as ceramides and diacylglycerols, especially within the skeletal muscle, appears to be instrumental in paving the path leading to worsening of metabolic complications. These metabolic consequences mostly interfere with the efficiency of the mitochondrial electron transport chain, leading to overproduction of toxic reactive oxygen species. Therefore, therapeutic agents that reverse the effects of lipid overload by improving insulin sensitivity and mitochondrial oxidative capacity are crucial for the management or even treatment of metabolic diseases.

Current Progress in Delineating the Roles of Pseudokinase TRIB1 in Controlling Human Diseases

Tribbles homolog 1 (TRIB1) is a member of the tribbles family of pseudoprotein kinases and is widely expressed in numerous tissues, such as bone marrow, skeletal muscle, liver, heart, and adipose tissue. It is closely associated with acute myeloid leukemia, prostate cancer, and tumor drug resistance, and can interfere with the hematopoietic stem cell cycle, promote tumor cell proliferation, and inhibit apoptosis. Recent studies have shown that TRIB1 can regulate acute and chronic inflammation by affecting the secretion of inflammatory factors, which is closely related to the occurrence of hyperlipidemia and cardiovascular diseases. Given the important biological functions of TRIB1, the reviews published till now are not sufficiently comprehensive. Therefore, this paper reviews the progress in TRIB1 research aimed at exploring its roles in cancer, hyperlipidemia, and cardiovascular disease, and providing a theoretical basis for further studies on the biological roles of TRIB1.

The S100 protein family in lung cancer

The S100 protein family is involved in the pathogenesis of several malignancies including lung cancer. Recent studies have shown that one member, S100A2, was over-expressed in advanced stage non-small cell lung cancer (NSCLC). Another, S100A6, demonstrated variable expression in different lung cancer subtypes. Research using NSCLC cell lines reported that SIX3 inhibited cell metastasis and proliferation via S100P down-regulation. This review represents an update on S100 proteins in lung cancer from 2017 to 2021 and includes the aforementioned as well as S100A4, S100A7, and S100B. Inconsistencies in mechanisms of action for S100A8/S100A9 are highlighted and a comprehensive evaluation of the most recent evidence for the S100 proteins in lung cancer is presented.

A novel evodiamine amino derivative as a PI3K/AKT signaling pathway modulator that induces apoptosis in small cell lung cancer cells

Evodiamine (EVO) was derivatized to a C10-amino derivative (EVA) using a two-step method suitable for industrializing production. This method has advantages such as a short reaction time, high yield, few byproducts and simple purification. The AUC and C_max values of EVA were 7.02- and 4.62-fold, while the T_max and Cl values were one-half and one-eighth that of EVO, respectively. EVA markedly improved the bioavailability, which might be ascribed to the serum albumin deposit effect. EVA was bound to albumin in the same hydrophobic pocket as EVO, but one more hydrogen bond was formed between Asp323 and the amino group at the C10 position. The amino derivative of natural alkaloids showed a substantial increase in antitumor activity on small cell lung cancer (SCLC) cells. The role of the PI3K/AKT signaling pathway in alkaloid/derivative-induced apoptosis in tumor cells was thoroughly described. p-AKT, its downstream effectors Bcl-2, Bax, caspase-3 and its upstream regulator PTEN were regulated by EVA. The interaction between EVO/EVA and the upstream protein PI3K p110 was first investigated with molecular docking. The apoptosis induced by EVA was abrogated after the PI3K/AKT signaling pathway was reactivated by IGF-1. The interaction between EVO/EVA and P-gp was also first studied using docking method. Their binding forces were weak. But EVA might reduce much expression of P-gp than EVO, and ultimately led to reduction of EVA efflux. Our study provides novel insights into a feasible and productive amino derivative of natural alkaloids for SCLC therapy.

Dysregulation of ferroptosis may involve in the development of non-small-cell lung cancer in Xuanwei area

The Xuanwei area of Yunnan Province, China, is one of the regions suffering from the highest occurrence and mortality rate of lung cancer in the world. Local residents tend to use bituminous coal as domestic fuel, which causes serious indoor air pollution and is established as the main carcinogen. After the local government carried out furnace and stove reform work, lung cancer rate including incidence and mortality among residents remains high. We herein wonder if there are specific mechanisms at protein level for the development of non-small-cell lung cancer (NSCLC) in this area. We investigated the changes of protein profiling in tumour of the patients from Xuanwei area. Tandem mass tag (TMT) was employed to screen the differential proteins between carcinoma and para-carcinoma tissues. We identified a total of 422 differentially expressed proteins, among which 162 proteins were significantly up-regulated and 260 were downregulated compared to para-carcinoma tissues. Many of the differentially expressed proteins were related to extracellular matrix (ECM)-receptor interaction, focal adhesion, PI3K/AKT pathway and ferroptosis. Further experiments on the two differential proteins, thioredoxin 2 (TXN2) and haptoglobin (HP), showed that the change of their expressions could make the lung cancer cell lines more resistant to erastin or RSL-induced ferroptosis in vitro, and promote the growth of tumour in nude mice. In conclusion, this study revealed that aberrant regulation of ferroptosis may involve in the development of lung cancer in Xuanwei area.

SGK1 in Human Cancer: Emerging Roles and Mechanisms

Serum and glucocorticoid-induced protein kinase 1 (SGK1) is a member of the "AGC" subfamily of protein kinases, which shares structural and functional similarities with the AKT family of kinases and displays serine/threonine kinase activity. Aberrant expression of SGK1 has profound cellular consequences and is closely correlated with human cancer. SGK1 is considered a canonical factor affecting the expression and signal transduction of multiple genes involved in the genesis and development of many human cancers. Abnormal expression of SGK1 has been found in tissue and may hopefully become a useful indicator of cancer progression. In addition, SGK1 acts as a prognostic factor for cancer patient survival. This review systematically summarizes and discusses the role of SGK1 as a diagnostic and prognostic biomarker of diverse cancer types; focuses on its essential roles and functions in tumorigenesis, cancer cell proliferation, apoptosis, invasion, metastasis, autophagy, metabolism, and therapy resistance and in the tumor microenvironment; and finally summarizes the current understanding of the regulatory mechanisms of SGK1 at the molecular level. Taken together, this evidence highlights the crucial role of SGK1 in tumorigenesis and cancer progression, revealing why it has emerged as a potential target for cancer therapy.

Microbiome: A Supportive or a Leading Actor in Lung Cancer?

Lung cancer is still the leading cause of cancer death worldwide. Despite the major diagnostic and therapeutic innovations, the effect on mortality has been modest and the overall survival is still poor. Better understanding of the pathology of these tumors is necessary in order to develop personalized therapeutic strategies in lung cancer patients. Human microbiome has been associated with normal physiology and function, and increasing evidence points towards a key role of the microbiome in promoting the progression of lung disease. Studies have shown that although poorly understood, lung has a distinctive microbiome that may an important role in lung cancer development and progression, and interactions between microbial populations have the potential to influence disease, suggesting that microbiome can be an emerging target in cancer therapeutics. We will review mechanisms how the lung microbiota influences carcinogenesis, focusing on the bacterial dysbiosis and inflammation. Moreover, we will discuss the link between the microbiome and cancer and the consequences induced by the immune system, as the host microbiota plays an essential role in activating and modulating the immune response. We summarize current research advances in the lung microbiome and demonstrate the potential to exploit microbiome as a mechanism to prevent carcinogenesis and modulate therapeutic strategy, suggesting microbiome as a valuable approach in lung cancer patients.

Bone marrow mesenchymal stem cell-derived exosomes alleviate hyperoxia-induced lung injury via the manipulation of microRNA-425

BACKGROUND

Hyperoxia-induced lung injury (HILI) is an acute lung injury (LI) induced by extended periods of exposure to hyperoxia. Alleviating LI by bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exos) and microRNAs (miRs) has been previously reported. This study is devised to probe the interaction between BMSCs-Exos and miR-425 in HILI.

METHODS

Firstly, BMSCs-Exos were isolated and identified. Then, HILI rat models and RLE-6TN cell models were successfully established and treated by BMSCs-Exos. Afterwards, functional assays were conducted to explore cell biological behaviors in models, with miR-425 expression detected. Then, the target relation between miR-425 and PTEN was clarified by luciferase reporter assay. Eventually, expression of PTEN and the PI3K/Akt axis was assessed by Western blotting and qRT-PCR.

RESULTS

BMSCs-Exos promoted miR-425 expression and attenuated HILI and H₂O₂ induced RLE-6TN cell injury as evidence by alleviated lung cell injury, decreased TUNEL-positive cells, induced cell viability and declined apoptosis (all p < 0.05). Besides, when miR-425 was knocked-down, the protective role of BMSCs-Exos in HILI was also reduced (all p < 0.05). miR-425 targeted PTEN mRNA, whose upregulation reversed the protective role of BMSCs-Exos in HILI (all p < 0.05). BMSCs-Exos improved the quenched levels of the PI3K/AKT axis in HILI (all p < 0.05).

CONCLUSION

Our data supported that miR-425 in BMSCs-Exos inhibits HILI by targeting PTEN and upregulating the PI3K/AKT axis. This study may provide personalized interventions for HILI remedy.

Mechanisms of tRNA-derived fragments and tRNA halves in cancer treatment resistance

The tRNA-derived fragments (tRFs) and tRNA halves (tiRNAs) are newly discovered noncoding RNAs in recent years. They are derived from specific cleavage of mature and pre-tRNAs and expressed in various cancers. They enhance cell proliferation and metastasis or inhibit cancer progression. Many studies have investigated their roles in the diagnosis, progression, metastasis, and prognosis of various cancers, but the mechanisms through which they are involved in resistance to cancer treatment are unclear. This review outlines the classification of tRFs and tiRNAs and their mechanisms in cancer drug resistance, thus providing new ideas for cancer treatment.

Effect of AKT1 (p. E17K) Hotspot Mutation on Malignant Tumorigenesis and Prognosis

The substitution of the seventeenth amino acid glutamate by lysine in the homologous structural domain of the Akt1 gene pleckstrin is a somatic cellular mutation found in breast, colorectal, and ovarian cancers, named p. Glu17Lys or E17K. In recent years, a growing number of studies have suggested that this mutation may play a unique role in the development of tumors. In this review article, we describe how AKT1(E17K) mutations stimulate downstream signals that cause cells to emerge transformed; we explore the differential regulation and function of E17K in different physiological and pathological settings; and we also describe the phenomenon that E17K impedes tumor growth by interfering with growth-promoting and chemotherapy-resistant AKT1^lowQCC generation, an intriguing finding that mutants may prolong tumor patient survival by activating feedback mechanisms and disrupting transcription. This review is intended to provide a better understanding of the role of AKT1(E17K) in cancer and to inform the development of AKT1(E17K)-based antitumor strategies.

High expression of EMP1 predicts a poor prognosis and correlates with immune infiltrates in bladder urothelial carcinoma

Epithelial membrane protein 1 (EMP1) is a key gene that regulates cell proliferation and metastatic capability in various types of cancer, and serves an important role in tumor-immune interactions. However, the association between EMP1 and clinical prognosis, as well as the presence of tumor-infiltrating lymphocytes in bladder urothelial carcinoma (BLCA) remains unclear. The present study aimed to explore the relationship between EMP1 expression and tumor immune cell infiltration in BLCA. In the present study, EMP1 expression in BLCA was analyzed using the Oncomine database, The Cancer Genome Atlas (TCGA) and the Tumor Immune Estimation Resource (TIMER). The effects of EMP1 on clinical prognosis were evaluated using the Kaplan-Meier plotter and Gene Expression Profiling Interactive Analysis. The correlations between EMP1, cancer immune infiltrates and lymphocyte abundance were determined using the TIMER and Tumor immune system interaction database. In addition, correlations between EMP1 expression and gene markers in immune infiltrates were analyzed using cBioportal. The results demonstrated that, compared with adjacent normal tissues, EMP1 was downregulated in BLCA tissues. High expression of EMP1 was significantly associated with poor overall survival (OS) in BLCA cases obtained from TCGA. Multivariate Cox analysis revealed that EMP1 was an independent predictor of OS in patients with BLCA. Gene set enrichment analysis revealed that EMP1 was associated with cancer-related pathways and was positively correlated with the levels of infiltrating CD8⁺ T cells, macrophages, neutrophils and dendritic cells in BLCA. Further analysis demonstrated that EMP1 was significantly associated with the enrichment of multiple types of lymphocyte. EMP1 expression exhibited a strong correlation with a range of immune markers in BLCA. In conclusion, the results of the present study demonstrated that EMP1 was associated with a poor prognosis in patients with BLCA, and that the levels of immune infiltration and multiple immunomarker groups were associated with EMP1 expression. These results suggested that EMP1 may be used as a predictive biomarker to determine the prognosis and immune infiltration in BLCA.

Inhibitors in AKTion: ATP-competitive vs allosteric

Aberrant activation of the PI3K pathway is one of the commonest oncogenic events in human cancer. AKT is a key mediator of PI3K oncogenic function, and thus has been intensely pursued as a therapeutic target. Multiple AKT inhibitors, broadly classified as either ATP-competitive or allosteric, are currently in various stages of clinical development. Herein, we review the evidence for AKT dependence in human tumours and focus on its therapeutic targeting by the two drug classes. We highlight the future prospects for the development and implementation of more effective context-specific AKT inhibitors aided by our increasing knowledge of both its regulation and some previously unrecognised non-canonical functions.

Identification of a 5-Gene Metabolic Signature for Predicting Prognosis Based on an Integrated Analysis of Tumor Microenvironment in Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is a common subtype of lung cancer with a depressing survival rate. The reprogramming of tumor metabolism was identified as a new hallmark of cancer in tumor microenvironment (TME), and we made a comprehensive exploration to reveal the prognostic role of the metabolic-related genes. Transcriptome profiling data of LUAD were, respectively, downloaded from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. Based on the extracted metabolic-related genes, a novel 5-gene metabolic prognostic signature (including GNPNAT1, LPGAT1, TYMS, LDHA, and PTGES) was constructed by univariate Cox regression and least absolute shrinkage and selection operator (LASSO) regression. This signature confirmed its robustness and accuracy by external validation in multiple databases. It could be an independent risk factor for LUAD, and the nomograms possessed moderately accurate performance with the C-index of 0.755 (95% confidence interval: 0.706–0.804) and 0.691 (95% confidence interval: 0.636–0.746) in training set and testing set. This signature could reveal the metabolic features according to the results of gene set enrichment analysis (GSEA) and meanwhile monitor the status of TME through ESTIMATE scores and the infiltration levels of immune cells. In conclusion, this gene signature is a cost-effective tool which could indicate the status of TME to provide more clues in the exploration of new diagnostic and therapeutic strategy.

Lung cancer A549 cells suppressed with overexpressed HNF1B or PCDHA13 inhibited PI3K/AKT phosphorylation

BACKGROUND

Lung cancer is the most revenant and deadly tumors around the world. Here we aimed to explore the effects of hepatocyte nuclear factor 1B (HNF1B) and PCDHA13 overexpression on PI3K/AKT phosphorylation and malignant biological behavior in lung cancer A549 cells.

METHODS

HNF1B and PCDHA13 were amplified, and their overexpression plasmids were constructed for transfection. RT-PCR was used to detect the mRNA levels of HNF1B and PCDHA13. Cell proliferation and cell apoptosis were detected by clone formation experiments and flow cytometry, respectively, while cell invasion was studied by Transwell assay. The expression of survivin, PCNA, Caspase-3, Caspase-9, VEGF, and fibronectin was detected using immunoblotting, as was PI3K/AKT phosphorylation.

RESULTS

The level of HNF1B mRNA expression was significantly higher in the pcNDA-HNF1B group than in the control group (P<0.05), and the level of PCDHA13 mRNA expression in the pcNDA-PCDHA13 group was also significantly increased (P<0.05). The clone formation rate and cell invasion count in pcNDA-HNF1B or pcNDA-PCDHA13 transfected groups were significantly reduced in comparison with the control group, which were further validated with the protein expression levels of survivin, PCNA, VEGF, and fibronectin (P<0.05). However, the apoptosis rate, and the cleaved caspase3/caspase3 and cleaved caspase9/caspase9 protein expression ratios were all significantly increased (P<0.05). Cells transfected with pcNDA-HNF1B or pcNDA-PCDHA13 showed decreased levels of PI3K/AKT phosphorylation (P<0.05).

CONCLUSIONS

Overexpression of HNF1B and PCDHA13 inhibits the phosphorylation of PI3K/AKT and hinders the malignant biological behavior of lung cancer A549 cells.

Functional roles of GDF15 in modulating microenvironment to promote carcinogenesis

Obesity and related metabolic dysregulation are risk factors for many types of cancer. The interactions between a developing tumor and its microenvironment are known to implicate a complex "crosstalk" among the factors produced by the population of cells. Among these factors, Growth and differentiation factor 15 (GDF15) has a functional role in cancer. GDF15 expression is induced in response to the conditions associated with cellular stress and diseases. The GDF15 receptor, a member of the glial-cell-derived neurotropic factor family (GDNF), is a GDNF family receptor α-like (GFRAL) protein. GDF15 induces pro-angiogenic effects in tumors. However, GDF15 could affect tumorigenesis both positively and negatively. With a better understanding of the upstream disease pathways reflected by GDF15, new treatment targets may emerge.

Activating Transcription Factor 3 (ATF3) Protects Retinal Ganglion Cells and Promotes Functional Preservation After Optic Nerve Crush

Purpose

To investigate the possible role of activating transcription factor 3 (ATF3) in retinal ganglion cell (RGC) neuroprotection and optic nerve regeneration after optic nerve crush (ONC).

Methods

Overexpression of proteins of interest (ATF3, phosphatase and tensin homolog [PTEN], placental alkaline phosphatase, green fluorescent protein) in the retina was achieved by intravitreal injections of recombinant adenovirus-associated viruses (rAAVs) expressing corresponding proteins. The number of RGCs and αRGCs was evaluated by immunostaining retinal sections and whole-mount retinas with antibodies against RNA binding protein with multiple splicing (RBPMS) and osteopontin, respectively. Axonal regeneration was assessed via fluorophore-coupled cholera toxin subunit B labeling. RGC function was evaluated by recording positive scotopic threshold response.

Results

The level of ATF3 is preferentially elevated in osteopontin⁺/RBPMS⁺ αRGCs following ONC. Overexpression of ATF3 by intravitreal injection of rAAV 2 weeks before ONC promoted RBPMS⁺ RGC survival and preserved RGC function as assessed by positive scotopic threshold response recordings 2 weeks after ONC. However, overexpression of ATF3 and simultaneous downregulation of PTEN, a negative regulator of the mTOR pathway, combined with ONC, only moderately promoted short distance RGC axon regeneration (200 μm from the lesion site) but did not provide additional RGC neuroprotection compared with PTEN downregulation alone.

Conclusions

These results reveal a neuroprotective effect of ATF3 in the retina following injury and identify ATF3 as a promising agent for potential treatments of optic neuropathies.

Early Dendritic Morphogenesis of Adult-Born Dentate Granule Cells Is Regulated by FHL2

Dentate granule cells (DGCs), the progeny of neural stem cells (NSCs) in the sub-granular zone of the dentate gyrus (DG), must develop and functionally integrate with the mature cohort of neurons in order to maintain critical hippocampal functions throughout adulthood. Dysregulation in the continuum of DGC development can result in aberrant morphology and disrupted functional maturation, impairing neuroplasticity of the network. Yet, the molecular underpinnings of the signaling involved in adult-born DGC maturation including dendritic growth, which correlates with functional integration, remains incompletely understood. Given the high metabolic activity in the dentate gyrus (DG) required to achieve continuous neurogenesis, we investigated the potential regulatory role of a cellular metabolism-linked gene recently implicated in NSC cycling and neuroblast migration, called Four and a half LIM domain 2 (FHL2). The FHL2 protein modulates numerous pathways related to proliferation, migration, survival and cytoskeletal rearrangement in peripheral tissues, interacting with the machinery of the sphingosine-1-phosphate pathway, also known to be highly active especially in the hippocampus. Yet, the potential relevance of FHL2 to adult-born DGC development remains unknown. To elucidate the role of FHL2 in DGC development in the adult brain, we first confirmed the endogenous expression of FHL2 in NSCs and new granule cells within the DG, then engineered viral vectors for genetic manipulation experiments, investigating morphological changes in early stages of DGC development. Overexpression of FHL2 during early DGC development resulted in marked sprouting and branching of dendrites, while silencing of FHL2 increased dendritic length. Together, these findings suggest a novel role of FHL2 in adult-born DGC morphological maturation, which may open up a new line of investigation regarding the relevance of this gene in physiology and pathologies of the hippocampus such as mesial temporal lobe epilepsy (MTLE).

LncARSR promotes non-small-cell lung cancer progression via regulating PTEN/Akt

LncRNAs have been suggested to be key modulators in many biological and pathological processes. LncARSR, a recently identified lncRNA, plays crucial roles in the progression of several cancers. However, the role of lncARSR in NSCLC is uninvestigated. In the present study, it was demonstrated that lncARSR expression was higher in NSCLC tissues than in noncancerous tissues. The expression of lncARSR was higher in four NSCLC cell lines than in a normal lung bronchial epithelial line. Further investigation demonstrated that increased lncARSR expression promoted NSCLC cell migration and growth and induced epithelial-mesenchymal transition in A549 cells. Moreover, ectopic expression of lncARSR suppressed PTEN expression and induced Akt phosphorylation in A549 cells. The expression level of PTEN was higher in NSCLC samples than in adjacent non-tumor specimens. PTEN expression was negatively correlated with lncARSR in NSCLC specimens. Furthermore, we demonstrated that overexpression of lncARSR induced NSCLC cell growth and migration via regulating the PTEN/Akt signaling pathway. These results suggest that lncARSR acts as an oncogene in NSCLC development and could serve as a new potential therapeutic target.

Sulforaphane: Expected to Become a Novel Antitumor Compound

Natural products are becoming increasingly popular in a variety of traditional, complementary, and alternative systems due to their potency and slight side effects. Natural compounds have been shown to be effective against many human diseases, especially cancers. Sulforaphane (SFE) is a traditional Chinese herbal medicine. In recent years, an increasing number of studies have been conducted to evaluate the antitumor effect of SFE. The roles of SFE in cancers are mainly through the regulation of potential biomarkers to activate or inhibit related signaling pathways. SFE has exhibited promising inhibitory effects on breast cancer, lung cancer, liver cancer, and other malignant tumors. In this review, we summarized the reports on the activity and functional mechanisms of SFE in cancer treatment and explored the efficacy and toxicity of SFE.

The detection and analysis of differential regulatory communities in lung cancer

The tumorgenesis process of lung cancer involves the regulatory dysfunctions of multiple pathways. Although many signaling pathways have been identified to be associated with lung cancer, there are little quantitative models of how inactions between genes change during the process from normal to cancer. These changes belong to different dynamic co-expressions patterns. We quantitatively analyzed differential co-expression of gene pairs in four datasets. Each dataset included a large number of lung cancer and normal samples. By overlapping their results, we got 14 highly confident gene pairs with consistent co-expression change patterns. Some of they, such as ARHGAP30 and GIMAP4, had been recorded in STRING network database while some of them were novel discoveries, such as C9orf135 and MORN5, TEKT1 and TSPAN1 were positively correlated in both normal and cancer but more correlated in normal than cancer. These gene pairs revealed the underlying mechanisms of lung cancer occurrence.

The Pivotal Roles of the Epithelial Membrane Protein Family in Cancer Invasiveness and Metastasis

The members of the family of epithelial membrane proteins (EMPs), EMP1, EMP2, and EMP3, possess four putative transmembrane domain structures and are composed of approximately 160 amino acid residues. EMPs are encoded by the growth arrest-specific 3 (GAS3)/peripheral myelin protein 22 kDa (PMP22) gene family. The GAS3/PMP22 family members play roles in cell migration, growth, and differentiation. Evidence indicates an association of these molecules with cancer progression and metastasis. Each EMP has pro- and anti-metastatic functions that are likely involved in the complex mechanisms of cancer progression. We have recently demonstrated that the upregulation of EMP1 expression facilitates cancer cell migration and invasion through the activation of a small GTPase, Rac1. The inoculation of prostate cancer cells overexpressing EMP1 into nude mice leads to metastasis to the lymph nodes and lungs, indicating that EMP1 contributes to metastasis. Pro-metastatic properties of EMP2 and EMP3 have also been proposed. Thus, targeting EMPs may provide new insights into their clinical utility. Here, we highlight the important aspects of EMPs in cancer biology, particularly invasiveness and metastasis, and describe recent therapeutic approaches.

The microbiome and cancer for clinicians

The human microbiome is an emerging target in cancer development and therapeutics. It may be directly oncogenic, through promotion of mucosal inflammation or systemic dysregulation, or may alter anti-cancer immunity/therapy. Microorganisms within, adjacent to and distant from tumors may affect cancer progression, and interactions and differences between these populations can influence the course of disease. Here we review the microbiome as it pertains to cancer for clinicians. The microbiota of cancers including colorectal, pancreas, breast and prostate are discussed. We examine "omics" technologies, microbiota associated with tumor tissue and tumor-site fluids such as feces and urine, as well as indirect effects of the gut microbiome. We describe roles of the microbiome in immunotherapy, and how it can be modulated to improve cancer therapeutics. While research is still at an early stage, there is potential to exploit the microbiome, as modulation may increase efficacy of treatments, reduce toxicities and prevent carcinogenesis.

Mechanisms of resistance to a PI3K inhibitor in gastrointestinal stromal tumors: an omic approach to identify novel druggable targets

Background: Gastrointestinal stromal tumors (GISTs) represent a worldwide paradigm of target therapy. The introduction of tyrosine kinase inhibitors has deeply changed the prognosis of GIST patients, however, the majority of them acquire secondary mutations and progress. Unfortunately, besides tyrosine-kinase inhibitors, no other therapeutic options are available. Therefore, it is mandatory to identify novel molecules and/or strategies to overcome the inevitable resistance. In this context, after promising preclinical data on the novel PI3K inhibitor BYL719, the NCT01735968 trial in GIST patients who had previously failed treatment with imatinib and sunitinib started. BYL719 has attracted our attention, and we comprehensively characterized genomic and transcriptomic changes taking place during resistance.

Methods: For this purpose, we generated two in vitro GIST models of acquired resistance to BYL719 and performed an omic-based analysis by integrating RNA-sequencing, miRNA, and methylation profiles in sensitive and resistant cells.

Results: We identified novel epigenomic mechanisms of pharmacological resistance in GISTs suggesting the existence of pathways involved in drug resistance and alternatively acquired mutations. Therefore, epigenomics should be taken into account as an alternative adaptive mechanism.

Conclusion: Despite the fact that currently we do not have patients in treatment with BYL719 to verify this hypothesis, the most intriguing result is the involvement of H19 and PSTA1 in GIST resistance, which might represent druggable targets.

ST6GAL1: A key player in cancer

Aberrant glycosylation is a universal feature of cancer cells and there is now overwhelming evidence that glycans can modulate pathways intrinsic to tumour cell biology. Glycans are important in all of the cancer hallmarks and there is a renewed interest in the glycomic profiling of tumours to improve early diagnosis, determine patient prognosis and identify targets for therapeutic intervention. One of the most widely occurring cancer associated changes in glycosylation is abnormal sialylation which is often accompanied by changes in sialyltransferase activity. Several sialyltransferases are implicated in cancer, but in recent years ST6 β-galactoside α-2,6-sialyltransferase 1 (ST6GAL1) has become increasingly dominant in the literature. ST6GAL1 catalyses the addition of α2,6-linked sialic acids to terminal N-glycans and can modify glycoproteins and/or glycolipids. ST6GAL1 is upregulated in numerous types of cancer (including pancreatic, prostate, breast and ovarian cancer) and can promote growth, survival and metastasis. The present review discusses ST6GAL in relation to the hallmarks of cancer, and highlights its key role in multiple mechanisms intrinsic to tumour cell biology.

Cathepsins: Potent regulators in carcinogenesis

Cathepsins (CTS) are mainly lysosomal acid hydrolases extensively involved in the prognosis of different diseases, and having a distinct role in tumor progression by regulating cell proliferation, autophagy, angiogenesis, invasion, and metastasis. As all these processes conjunctively lead to cancer progression, their site-specific regulation might be beneficial for cancer treatment. CTS regulate activation of the proteolytic cascade and protein turnover, while extracellular CTS is involved in promoting extracellular matrix degradation and angiogenesis, thereby stimulating invasion and metastasis. Despite cancer regulation, the involvement of CTS in cellular adaptation toward chemotherapy and radiotherapy augments their therapeutic potential. However, lysosomal permeabilization mediated cytosolic translocation of CTS induces programmed cell death. This complex behavior of CTS generates the need to discuss the different aspects of CTS associated with cancer regulation. In this review, we mainly focused on the significance of each cathepsin in cancer signaling and their targeting which would provide noteworthy information in the context of cancer biology and therapeutics.

Solid stress-induced migration is mediated by GDF15 through Akt pathway activation in pancreatic cancer cells

Solid stress is a biomechanical abnormality of the tumor microenvironment that plays a crucial role in tumor progression. When it is applied to cancer cells, solid stress hinders their proliferation rate and promotes cancer cell invasion and metastatic potential. However, the underlying mechanisms of how it is implicated in cancer metastasis is not yet fully understood. Here, we used two pancreatic cancer cell lines and an established in vitro system to study the effect of solid stress-induced signal transduction on pancreatic cancer cell migration as well as the mechanism involved. Our results show that the migratory ability of cells increases as a direct response to solid stress. We also found that Growth Differentiation Factor 15 (GDF15) expression and secretion is strongly upregulated in pancreatic cancer cells in response to mechanical compression. Performing a phosphoprotein screening, we identified that solid stress activates the Akt/CREB1 pathway to transcriptionally regulate GDF15 expression, which eventually promotes pancreatic cancer cell migration. Our results suggest a novel solid stress signal transduction mechanism bringing GDF15 to the centre of pancreatic tumor biology and rendering it a potential target for future anti-metastatic therapeutic innovations.

Identification of an eight-gene prognostic signature for lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related death worldwide. The main obstacle to early diagnosis or monitoring of patients at high risk of poor survival has been the lack of essential predictive biomarkers.

METHODS

RNA-sequencing was performed on LUAD affected tissue and paired adjacent to noncancerous tissue samples and Gene Expression Omnibus dataset GSE19188 and GSE33532 were used to obtain an intersection of differential expressed genes and construct a protein-protein interaction network to get hub genes. Then corresponding overall survival information of two cohorts of LUAD patients from our hospital and The Cancer Genome Atlas project-LUAD were included in the present study. An analysis of the Kyoto Encyclopedia of Genes and Genomes database and Gene Ontology were carried out to study the signature mechanism.

RESULTS

In our study, we identified eight candidate genes (DLGAP5, KIF11, RAD51AP1, CCNB1, AURKA, CDC6, OIP5 and NCAPG) closely related to survival in LUAD. A linear prognostic model of the eight genes was constructed and weighted by the regression coefficient (β) from the multivariate Cox regression analysis of The Cancer Genome Atlas-LUAD cohort to divide patients into low- and high-risk groups. The prognostic ability of the signature was validated in LUAD patients at our hospital. Patients assigned to the high-risk group exhibited poor overall survival compared to patients in the low-risk group. Finally, functional enrichment analysis showed that cell division played a vital role in the development of LUAD.

CONCLUSION

The study identified an mRNA signature including eight genes, which may serve as a potential prognostic marker of LUAD.

Airway brushing as a new experimental methodology to detect airway gene expression signatures in mouse lung squamous cell carcinoma

As a consequence of exposure to environmental toxicants, a “field cancerization” effect occurs in the lung, resulting in the development of a field of initiated, but morphologically normal appearing cells within a damaged epithelium containing mutations in oncogene or tumor suppressor genes. Unlike humans, whose airway field of injury associated with lung cancer has long been investigated with airway brushings obtained via bronchoscopy, no methods are available for similar studies in the mouse due to the small size of the murine airways. In this protocol, we describe a detailed method for performing airway brushing from a live mouse, which enables repeated sampling from the same mouse and thus, mimicking the bronchoscopy protocol used in humans. Using this approach in the N-nitroso-tris-chloroethylurea (NTCU)-induced mouse lung squamous cell carcinoma (SCC) model, we isolated airway epithelial cells with intact cell membrane structure and then performed transcriptome sequencing (RNA-Seq). We found activation of the PI3K signaling network to be the most significant in cytologically normal bronchial airway epithelial cells of mice with preneoplastic lung SCC lesions. Prolonged exposure to NTCU also induced activation of NF-kappaB (NFƙB), the downstream pathway of PI3K; this NTCU-induced lung SCC progression can be reversed by blocking the NFƙB pathway.

Silencing of Long Non-coding RNA MIAT Sensitizes Lung Cancer Cells to Gefitinib by Epigenetically Regulating miR-34a

Long non-coding RNA (lncRNA) myocardial infarction associated transcript (MIAT) was recently identified as oncogene in several cancers. However, the role of MIAT on acquired resistance in lung cancer and the underlying mechanisms remain unclear. Here, we showed that the expression of MIAT in lung cancer tissues was upregulated compared with adjacent tissues. LncRNA MIAT expression was associated with tumor size, lymph node metastasis, distant metastasis and TNM stage. Univariate analysis and multivariate analysis revealed that the lncRNA MIAT to be an independent factor for predicating the prognosis of lung cancer patients. Low lncRNA MIAT have longer overall survival time and progression-free survival time than patients with high lncRNA MIAT expression. Moreover, the knockdown of MIAT significantly sensitized PC9 and gefitinib-resistant PC9 cells to gefitinib in vitro and in vivo, and increased the expression of miR-34a and inactivated PI3K/Akt signaling. MIAT interacted with miR-34a and epigenetically controlled the miR-34a expression by hyper-methylating its promotor. Taken together, our findings demonstrated that knockdown of MIAT by siRNA enhances lung cancer cells to gefitinib through the PI3K/Akt signaling pathway by epigenetically regulating miR-34a. Thus, MIAT may be a useful prognostic marker and therapeutic target for lung cancer patients.

Long non-coding RNA GAS5 suppresses pancreatic cancer metastasis through modulating miR-32-5p/PTEN axis

Background

Long non-coding RNA growth arrest-specific transcript 5 (lncRNA GAS5) is a well-known tumor suppressor in the pathogenesis of a variety of human cancers. The precise role of GAS5 in pancreatic cancer (PC) progression is currently unknown, so the aim of this study was to explore the functional participation of GAS5 in PC metastasis.

Methods

The expression changes of GAS5, miR-32-5p and PTEN in human PC specimens and cell lines were compared by means of molecular biology methods. Transfection of the recombinant plasmid was applied to modulate the expression levels of the target genes. RIP and RNA pull-down assays were designed to investigate the interaction between GAS5 and miR-32-5p. The effect of GAS5 and miR-32-5p on PC progression was assessed with cell proliferation, migration, invasion and apoptosis in vitro.

Results

GAS5 and PTEN protein were decreased in human PC tissues and cells, but miR-32-5p was increased. GAS5 induction greatly inhibited the proliferation, migration and invasion of PC cells PANC-1 and BxPC-3 in vitro and simultaneously induced cell apoptosis. Moreover, GAS5 positively regulated the expression of PTEN through miR-32-5p. Furthermore, GAS5 suppressed the proliferation, migration and invasion of PC cells through regulating miR-32-5p/PTEN axis. Additionally, this finding was further supported by the results of in vivo experiments.

Conclusion

GAS5 could positively regulate PTEN-induced tumor-suppressor pathway via miR-32-5p, thereby suppressing PC metastasis.

Electronic supplementary material

The online version of this article (10.1186/s13578-017-0192-0) contains supplementary material, which is available to authorized users.