Cytosolic THUMPD1 promotes breast cancer cells invasion and metastasis via the AKT-GSK3-Snail pathway

RNA ac4C modification in cancer: Unraveling multifaceted roles and promising therapeutic horizons

RNA modifications play a crucial role in cancer development, profoundly influencing various stages of the RNA lifecycle. These stages encompass nuclear processing, nuclear export, splicing, and translation in the cytoplasm. Among RNA modifications, RNA ac4C modification, also known as N4-acetylcytidine, stands out for its unique role in acetylation processes. Specific proteins regulate RNA ac4C modification, maintaining the dynamic and reversible nature of these changes. This review explores the molecular mechanisms and biological functions of RNA ac4C modification. It examines the intricate ways in which RNA ac4C modification influences the pathogenesis and progression of cancer. Additionally, the review provides an integrated overview of the current methodologies for detecting RNA ac4C modification. Exploring the potential applications of manipulating this modification suggests avenues for novel therapeutic strategies, potentially leading to more effective cancer treatments in the future.

RNA-binding protein THUMPD2 inhibits proliferation and promotes metastasis in epithelial ovarian cancer

Ovarian cancer (OC) is a common and lethal gynaecological malignancy. RNA-binding proteins (RBPs) play a crucial role in governing RNA metabolism and have been implicated in the development and progression of diverse cancer types. Slight alterations in RBPs' expression or activity can induce substantial modifications in the regulatory network. THUMPD2, as member of the RBP family, was found to have differential expression in ovarian cancer, with the mechanism has not been studied yet. In this study, THUMPD2 protein was found to be weakly expressed in the early (I + II) stages of OC (P = 0.013), with a low expression rate of 78.6 %, and highly expressed in late (III + IV) stages (P = 0.009), with a high expression rate of 84.8 %. The shRNA-mediated knockdown of THUMPD2 in OVCAR3 and SKOV3 cells resulted in increased cell proliferation but inhibited metastasis, whereas THUMPD2 overexpression had the opposite effect. THUMPD2 overexpression suppressed tumour growth in vivo. Conversely, low THUMPD2 expression promoted tumour growth. Furthermore, we identified the potential target genes and pathways of THUMPD2 using GO and KEGG analyses, which were related to the centrosome, microtubules, cell cycle, and extracellular matrix. We demonstrated that low expression of THUMPD2 in the early stage promoted tumour growth and high expression in the late stage promoted tumour metastasis. Our findings reveal the dual function of THUMPD2 in OC and suggest that THUMPD2 may serve as a therapeutic target for the treatment of OC.

Glucocorticoid receptor: a harmonizer of cellular plasticity in breast cancer-directs the road towards therapy resistance, metastatic progression and recurrence

Recent therapeutic advances have significantly uplifted the quality of life in breast cancer patients, yet several impediments block the road to disease-free survival. This involves unresponsiveness towards administered therapy, epithelial to mesenchymal transition, and metastatic progression with the eventual appearance of recurrent disease. Attainment of such characteristics is a huge adaptive challenge to which tumour cells respond by acquiring diverse phenotypically plastic states. Several signalling networks and mediators are involved in such a process. Glucocorticoid receptor being a mediator of stress response imparts prognostic significance in the context of breast carcinoma. Involvement of the glucocorticoid receptor in the signalling cascade of breast cancer phenotypic plasticity needs further elucidation. This review attempted to shed light on the inter-regulatory interactions of the glucocorticoid receptor with the mediators of the plasticity program in breast cancer; which may provide a hint for strategizing therapeutics against the glucocorticoid/glucocorticoid receptor axis so as to modulate phenotypic plasticity in breast carcinoma.

Combining lapatinib and palbociclib inhibits cell proliferation and invasion via AKT signaling pathway in endocrine-resistant breast cancer cells

Endocrine therapy plays a critical role in patients with hormone receptor-positive breast cancer. Endocrine-resistant breast cancer cells exhibit more HER2 signaling proteins (pAKT and pERK) and mesenchymal biomarkers than wild-type cell lines. In head and neck squamous cell carcinoma, the combination of lapatinib and palbociclib demonstrated synergistic inhibitory effects on cell proliferation and suppressed ERK1/2 phosphorylation. The combination of lapatinib and palbociclib at half-maximal inhibitory concentrations resulted in an increasing cytotoxic effect on cell proliferation. Furthermore, invasion activity was significantly decreased when combining two drugs at nontoxic concentrations more than either single drug alone did. The combination also remarkably suppressed epithelial-mesenchymal transition transcription factors, such as Snail and pAKT, more than monotherapy. Combining drugs, particularly lapatinib and palbociclib for targeting endocrine-resistant breast cancer cells whose tumors overexpressed HER2 after resistance to hormonal therapy, demonstrated better antiproliferative, anti-invasive effects, and suppression of EMT protein and pAKT than a single drug. These results could be from the interruption of the EMT process via the AKT pathway. Thus, this study provides preliminary data for applying this combination to patients with endocrine-resistant breast cancer in further clinical trials.

The emerging roles of ac4C acetylation "writer" NAT10 in tumorigenesis: A comprehensive review

The quick progress of epigenetic study has kindled new hope for treating many cancers. When it comes to RNA epigenetics, the ac4C acetylation modification is showing promise, whereas N-acetyltransferase 10 plays a wide range of biological functions, has a significant impact on cellular life events, and is frequently highly expressed in many malignant tumors. N-acetyltransferase 10 is an acetyltransferase with important biological involvement in cellular processes and lifespan. Because it is highly expressed in many malignant tumors, it is considered a pro-carcinogenic gene. The review aims to introduce NAT10, summarize the effects of ac4C acetylation on tumor growth from multiple angles, and discuss the possible therapeutic targeting of NAT10 and the future directions of ac4C acetylation investigations.

PCMT1 regulates the migration, invasion, and apoptosis of prostate cancer through modulating the PI3K/AKT/GSK-3β pathway

Protein L-isoaspartate (D-aspartate) O-methyltransferase (PCMT1) is a repair enzyme that catalyzes the conversion of isomerized aspartic acid (iso-Asp) residues into their normal structure, thereby restoring the configuration and function of proteins. Studies have shown that PCMT1 is overexpressed in several tumors and affects patients' prognosis. However, there are few reports on the role of PCMT1 in prostate cancer (PCa). In the present research, with the assistance of The Cancer Genome Atlas Program (TCGA) database, we found that PCMT1 was overexpressed in PCa tissues. The results of quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blot and immunohistochemistry staining also showed that PCMT1 expression was significantly increased in PCa tissues and cell lines. In PCa clinical samples, PCMT1 expression was closely related to Gleason score, clinical stage, lymph node metastasis and bone metastasis. The experiments of overexpression and knockdown of PCMT1 in vitro or in vivo showed that PCMT1 can significantly promote the proliferation, migration and invasion of PCa cells, inhibit cell apoptosis, and promote the growth of PCa. We furthermore confirmed that PCMT1 regulated the migration, invasion and apoptosis of PCa cells by modulating the phosphatidylinositol 3-kinase/AKT kinase/glycogen-synthase kinase-3β (PI3K/AKT/GSK-3β) signaling pathway. Collectively, PCMT1 plays a cancer-facilitative role in PCa by promoting the proliferation, migration and invasion of PCa cells, and inhibiting apoptosis. Therefore, PCMT1 is considered to represent a novel target for treating PCa.

Emerging role of RNA acetylation modification ac4C in diseases: Current advances and future challenges

The oldest known highly conserved modification of RNA, N4-acetylcytidine, is widely distributed from archaea to eukaryotes and acts as a posttranscriptional chemical modification of RNA, contributing to the correct reading of specific nucleotide sequences during translation, stabilising mRNA and improving transcription efficiency. Yeast Kre33 and human NAT10, the only known authors of ac4C, modify tRNA with the help of the Tan1/THUMPD1 adapter to stabilise its structure. Currently, the mRNA for N4-acetylcytidine (ac4C), catalysed by NAT10 (N-acetyltransferase 10), has been implicated in a variety of human diseases, particularly cancer. This article reviews advances in the study of ac4C modification of RNA and the ac4C-related gene NAT10 in normal physiological cell development, cancer, premature disease and viral infection and discusses its therapeutic promise and future research challenges.

The activation of EP300 by F11R leads to EMT and acts as a prognostic factor in triple-negative breast cancers

Cancer progression is influenced by junctional adhesion molecule (JAM) family members. The relationship between JAM family members and different types of cancer was examined using The Cancer Genome Atlas dataset. mRNA levels of the F11R (F11 receptor) in tumours were inversely correlated to the expression of JAM-2 and JAM-3. This relationship was unique to breast cancer (BCa) and was associated with poor prognosis (p = 0.024, hazard ratio = 1.44 [1.05-1.99]). A 50-gene molecular signature (prediction analysis of microarray 50) was used to subtype BCa. F11R mRNA expression significantly increased in human epidermal growth factor receptor 2 (HER2)-enriched (p = 0.0035) and basal-like BCa tumours (p = 0.0005). We evaluated F11R protein levels in two different compositions of BCa subtype patient tissue array cohorts to determine the relationship between BCa subtype and prognosis. Immunohistochemistry staining revealed that a high F11R protein level was associated with poor overall survival (p < 0.001; Taipei Medical University [TMU] cohort, p < 0.001; Kaohsiung Veterans General Hospital [KVGH] cohort) or disease-free survival (p < 0.001 [TMU cohort], p = 0.034 [KVGH cohort]) in patients with BCa. Comparison of F11R levels in different subtypes revealed the association of poor prognosis with high levels of F11R among luminal (p < 0.001 [TMU cohort], p = 0.027 [KVGH cohort]), HER2 positive (p = 0.018 [TMU cohort], p = 0.037 [KVGH cohort]), and triple-negative (p = 0.013 [TMU cohort], p = 0.037 [KVGH cohort]) BCa. F11R-based RNA microarray analysis and Ingenuity Pathway Analysis were successful in profiling the detailed gene ontology of triple-negative BCa cells regulated by F11R. The EP300 transcription factor was highly correlated with F11R in BCa (R = 0.51, p < 0.001). By analysing these F11R-affected molecules with the L1000CDs datasets, we were able to predict some repurposing drugs for potential application in F11R-positive BCa treatment.

Transfer RNA Modification Enzymes with a Thiouridine Synthetase, Methyltransferase and Pseudouridine Synthase (THUMP) Domain and the Nucleosides They Produce in tRNA

The existence of the thiouridine synthetase, methyltransferase and pseudouridine synthase (THUMP) domain was originally predicted by a bioinformatic study. Since the prediction of the THUMP domain more than two decades ago, many tRNA modification enzymes containing the THUMP domain have been identified. According to their enzymatic activity, THUMP-related tRNA modification enzymes can be classified into five types, namely 4-thiouridine synthetase, deaminase, methyltransferase, a partner protein of acetyltransferase and pseudouridine synthase. In this review, I focus on the functions and structures of these tRNA modification enzymes and the modified nucleosides they produce. Biochemical, biophysical and structural studies of tRNA 4-thiouridine synthetase, tRNA methyltransferases and tRNA deaminase have established the concept that the THUMP domain captures the 3'-end of RNA (in the case of tRNA, the CCA-terminus). However, in some cases, this concept is not simply applicable given the modification patterns observed in tRNA. Furthermore, THUMP-related proteins are involved in the maturation of other RNAs as well as tRNA. Moreover, the modified nucleosides, which are produced by the THUMP-related tRNA modification enzymes, are involved in numerous biological phenomena, and the defects of genes for human THUMP-related proteins are implicated in genetic diseases. In this review, these biological phenomena are also introduced.

Shikonin inhibits the proliferation of cervical cancer cells via FAK/AKT/GSK3β signalling

Cervical cancer is one of the most lethal malignancies of the female reproductive system. Shikonin, a naphthoquinone pigment extracted from the traditional medicinal herb, Lithospermum erythrorhizon, has been demonstrated to exert significant inhibitory effects on a variety of tumours in vitro and in vivo. In the present study, the effects of shikonin on cervical cancer and the underlying mechanisms were investigated. The effects of shikonin on the viability on HeLa and SiHa cervical cancer cells was examined using cell counting kit (CCK-8) and colony formation assays. Immunofluorescence assay was performed to detect the levels of the proliferation-related protein, Ki67. Western blot analysis was utilized to measure the phosphorylated and total expression levels of proteins, including focal adhesion kinase (FAK), AKT, and glycogen synthase kinase 3β (GSK3β). Cell migration was determined by using wound healing assay. Metastasis-associated 1 (MTA1), TGFβ1 and VEGF mRNA expression levels were determined using reverse transcription-quantitative PCR. It was demonstrated that, shikonin inhibited cervical cancer cell proliferation and migration. The data of the present study revealed that shikonin inhibited the proliferation of HeLa and SiHa cells in a concentration- and time-dependent manner. Mechanistically, shikonin blocked the proliferation of cervical cancer cells by downregulating the phosphorylation of FAK, AKT and GSK3β induced by EGF. In addition, shikonin significantly suppressed cell migration and reduced the expression of migration-related proteins, including MTA1, TGFβ1 and VEGF. On the whole, the present study demonstrates that shikonin may exert an inhibitory effect on the cervical cancer cell proliferation and migration through the FAK/AKT/GSK3β signaling pathway. These findings suggest that shikonin may function as a potential therapeutic drug for the treatment of cervical cancer.

Modified Sijunzi Decoction Inhibits Epithelial-Mesenchymal Transition of Non-Small Cell Lung Cancer by Attenuating AKT/GSK3β Pathway in vitro and in vivo

Modified Sijunzi Decoction (MSJZD) is an empirical prescription of Traditional Chinese Medicine (TCM) and has been corroborated to be effective in multiple human diseases, but its role in non-small cell lung cancer (NSCLC) is enigmatic. Here we mainly analyze the function and mechanism of MSJZD in NSCLC. In this study, we used a method that coupled ultra-performance liquid chromatography to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) to investigate the major constituents in MSJZD with positive and negative ion modes. Additionally, in in vitro experiments, the effects of serum-containing MSJZD on the biological behavior of NSCLC cells induced by TGF-β1 were assessed by cell function experiments. Then, the influences of serum-containing MSJZD on epithelial-mesenchymal transition (EMT)-related markers were examined by immunofluorescence and western blot assays. Also, the AKT/GSK3β pathway and apoptosis-related markers were estimated by western blotting. Tumor xenografts were generated by subcutaneously injecting A549 cells into BALB/c nude mice to determine the effects of MSJZD in vivo. We first analyzed the composition of MSJZD. In positive ion mode, 47 kinds of components were identified. In negative ion mode, 45 kinds of components were identified. We also found that TGF-β1 contributed to inducing cell morphological changes and EMT progression. In vitro, surprisingly, cell proliferation, migration as well as invasion in NSCLC cells induced by TGF-β1, could be weakened by serum-containing MSJZD, and apoptosis was intensified. Moreover, serum-containing MSJZD weakened EMT passage and AKT/GSK3β pathway activation and induced apoptosis-related markers in NSCLC cells triggered by TGF-β1. In vivo, we discovered that MSJZD attenuated the tumor growth, promoted histopathological damage, and induced apoptosis in A549 tumor-bearing mice. Importantly, MSJZD has also restrained the development of EMT, AKT/GSK3β pathway, and TGF-β1 expression levels in nude mice. These findings demonstrated that MSJZD significantly weakened NSCLC progression by modulating EMT and AKT/GSK3β pathway.

Pan-cancer analysis of N4-acetylcytidine adaptor THUMPD1 as a predictor for prognosis and immunotherapy

Background: THUMPD1 is a specific RNA adaptor that assists acetylation of mRNA and production of N4-acetylcytidine (ac4C). However, it remains unclear whether THUMPD1 plays a part in tumorigenesis and therapeutic efficacy. Here, we analyzed the expression profiles and prognostic value of THUMPD1 in pan-cancer and gained insights into the correlation between THUMPD1 expression level and immunotherapy efficacy.

Methods: Gene expression pattern and its correlation with prognosis, immune cell infiltration in pan-cancer were obtained from Genotype-Tissue Expression (GTEx), Cancer Cell Line Encyclopedia (CCLE) and The Cancer Genome Atlas (TCGA) databases, with Kaplan–Meier method and Spearman correlation analysis used. Western blotting and immunofluorescence on clinical samples were performed to validate our database-derived results. Correlation between THUMPD1 expression level and immunotherapy responses was also explored, based on clinical cohorts receiving programmed cell death protein 1 ligand (PD-L1) antibody therapy. Finally, gene set enrichment analysis (GSEA) was performed to show the possible tumorigenic mechanism.

Results: THUMPD1 was highly expressed in most cancer types, and this elevated expression indicated poor or improved prognosis for different cancers. In kidney renal clear cell carcinoma (KIRC) and rectum adenocarcinoma (READ), patients with higher THUMPD1 expression exhibited a better prognosis, while liver hepatocellular carcinoma (LIHC) patients had worse prognosis. Besides, THUMPD1 was significantly associated with immune cell infiltration, tumor mutational burden (TMB), microsatellite instability (MSI), immune checkpoints and neoantigen in many cancer types. Further, more clinical advantages and therapeutic responses were observed in patients with high THUMPD1 expression.

Conclusions: THUMPD1 may serve as a novel predictor to evaluate cancer prognosis and immune therapy efficacy in diverse cancer types.

MiR-873-5p targets THUMPD1 to inhibit gastric cancer cell behavior and chemoresistance

Background

Gastric cancer is one of the most common gastrointestinal tumors. Evidence has pointed to the fact that miRNAs play critical roles in the occurrence, development, and metastasis of gastric cancer by regulating cell proliferation, differentiation, apoptosis, and invasion.

Methods

In this study, first the relationship of miR-873-5p level and tissues types/LN(+/-)/metastasis(+/-)/tumor size was analysis, respectively. Second, the CCK8 and Transwell assay was used to determine the proliferation, invasion and migration of GC cells transfected with overexpression-/low expression-miR-873-5p. Third, the cell viability were analysis in the GC cells transfected with overexpression-/low expression-miR-873-5p treatment with different chemotherapy drugs. Fourth, the target gene of miR-873-5p was predicted using bioinformation methods. Fifth, the relationship of miR-873-5p with target gene-THUMPD1 were explored by using Wb and luciferase activity assay, et al.

Results

We confirmed that miR-873-5p was negatively correlated with GC including tumor size, LN metastasis, distant metastasis. The miR-873-5p enhanced the sensitivity of Doxorubicin/Fluorouracil and cisplatin. The THUMPD1 was the target gene of miR-873-5p. Moreover, miR-873-5p could target the THUMPD1 axis so as to inhibit gastric cancer cell behavior as well as chemoresistance.

Conclusions

MiR-873-5p plays a role in regulating cell behavior as well as regulating chemoresistance in gastric cancer. In addition, THUMPD1, as a downstream molecule of miR-873-5p, plays an important role in the cell behavior and chemoresistance of gastric cancer. The research first confirmed that miR-873-5p could inhibit gastric cancer cell behavior and chemoresistance by targeting the THUMPD1.

Role of tRNAs in Breast Cancer Regulation

Increased proliferation and protein synthesis are characteristics of transformed and tumor cells. Although the components of the translation machinery are often dysregulated in cancer, the role of tRNAs in cancer cells has not been well studied. Nevertheless, the number of related studies has recently started increasing. With the development of high throughput technologies such as next-generation sequencing, genome-wide differential tRNA expression patterns in breast cancer-derived cell lines and breast tumors have been investigated. The genome-wide transcriptomics analyses have been linked with many studies for functional and phenotypic characterization, whereby tRNAs or tRNA-related fragments have been shown to play important roles in breast cancer regulation and as promising prognostic biomarkers. Here, we review their expression patterns, functions, prognostic value, and potential therapeutic use as well as related technologies.

The role of GSK3 in metabolic pathway perturbations in cancer

Malignant transformation and tumor progression are accompanied by significant perturbations in metabolic programs. As such, cancer cells support high ATP turnover to construct the building blocks needed to fuel neoplastic growth. The coordination of metabolic networks in malignant cells is dependent on the collaboration with cellular signaling pathways. Glycogen synthase kinase 3 (GSK3) lies at the convergence of several signaling axes, including the PI3K/AKT/mTOR, AMPK, and Wnt pathways, which influence cancer initiation, progression and therapeutic responses. Accordingly, GSK3 modulates metabolic processes, including protein and lipid synthesis, glucose and mitochondrial metabolism, as well as autophagy. In this review, we highlight current knowledge of the role of GSK3 in metabolic perturbations in cancer.

Human transfer RNA modopathies: diseases caused by aberrations in transfer RNA modifications

tRNA molecules are post-transcriptionally modified by tRNA modification enzymes. Although composed of different chemistries, more than 40 types of human tRNA modifications play pivotal roles in protein synthesis by regulating tRNA structure and stability as well as decoding genetic information on mRNA. Many tRNA modifications are conserved among all three kingdoms of life, and aberrations in various human tRNA modification enzymes cause life-threatening diseases. Here, we describe the class of diseases and disorders caused by aberrations in tRNA modifications as 'tRNA modopathies'. Aberrations in over 50 tRNA modification enzymes are associated with tRNA modopathies, which most frequently manifest as dysfunctions of the brain and/or kidney, mitochondrial diseases, and cancer. However, the molecular mechanisms that link aberrant tRNA modifications to human diseases are largely unknown. In this review, we provide a comprehensive compilation of human tRNA modification functions, tRNA modification enzyme genes, and tRNA modopathies, and we summarize the elucidated pathogenic mechanisms underlying several tRNA modopathies. We will also discuss important questions that need to be addressed in order to understand the molecular pathogenesis of tRNA modopathies.

Molecular dynamics simulation, free energy landscape and binding free energy computations in exploration the anti-invasive activity of amygdalin against metastasis

BACKGROUND AND OBJECTIVE

Historically, amygdalin has been used as alternative medicine or in vitro and in vivo studies, but no single study exists which discusses the structural mechanism of amygdalin at a molecular level. This paper inquiries into the inhibitory actions of amygdalin on the selected targets: AKT1, FAK, and ILK, which are regulators for various mediated signaling pathways, and are associated with cell adhesion, migration, and differentiation. In order to get details at the molecular level of amygdalin's inhibitory activities against chosen proteins, molecular modeling and simulation techniques including double docking, molecular dynamics simulation, free energy landscape analysis, and binding free energy calculation were exerted.

METHODS

To get molecular level details of amygdalin inhibitory effects against the relevant proteins; here the utilized tools are the following: the double docking, molecular dynamics simulation, free energy landscape analysis, g_mmpbsa, and interaction entropy were used to evaluate the inhibitory activity against targeted proteins.

RESULTS

The computational calculations revealed that amygdalin inhibits the selected targets via block the ATP-binding pocket of AKT1, FAK, and ILK by forming stable hydrogen bonds. Moreover, free energy landscape, FEL exposed that amygdalin stabilized the global conformations of both FAK and ILK proteins to the minimum global energy besides it reduced the essential dynamics of FAK and ILK proteins. MMPBSA computations provided further evidence for amygdalin's stability inside the ATP-binding pocket of AKT1, FAK, and ILK with a binding free energy of 45.067, -13.033, 13.109 kJ/mol, respectively. The binding free energies are lastly consistent with the hydrogen bonding and pairs within 0.35 nm results. The decomposition of binding energy shows the pivotal amino acid residues responsible for the stability of amygdalin's interactions inside the ATP-binding sites by forming hydrogen bonds.

CONCLUSIONS

Before this work, it was enigmatic to make predictions about how amygdalin inhibits metastasis of cancer. But the computational results contribute in several ways to our understanding of amygdalin activity and provide a basic insight into the activity of amygdalin as a multi-target drug in the metastasis and invasion of cancer.

Proteomic analysis enables distinction of early- versus advanced-stage lung adenocarcinomas

Background

A gel‐free proteomic approach was utilized to perform in‐depth tissue protein profiling of lung adenocarcinoma (ADC) and normal lung tissues from early and advanced stages of the disease. The long‐term goal of this study is to generate a large‐scale, label‐free proteomics dataset from histologically well‐classified lung ADC that can be used to increase further our understanding of disease progression and aid in identifying novel biomarkers.

Methods and results

Cases of early‐stage (I‐II) and advanced‐stage (III‐IV) lung ADCs were selected and paired with normal lung tissues from 22 patients. The histologically and clinically stratified human primary lung ADCs were analyzed by liquid chromatography‐tandem mass spectrometry. From the analysis of ADC and normal specimens, 4863 protein groups were identified. To examine the protein expression profile of ADC, a peak area‐based quantitation method was used. In early‐ and advanced‐stage ADC, 365 and 366 proteins were differentially expressed, respectively, between normal and tumor tissues (adjusted P‐value < .01, fold change ≥ 4). A total of 155 proteins were dysregulated between early‐ and advanced‐stage ADCs and 18 were suggested as early‐specific stage ADC. In silico functional analysis of the upregulated proteins in both tumor groups revealed that most of the enriched pathways are involved in mRNA metabolism. Furthermore, the most overrepresented pathways in the proteins that were unique to ADC are related to mRNA metabolic processes.

Conclusions

Further analysis of these data may provide an insight into the molecular pathways involved in disease etiology and may lead to the identification of biomarker candidates and potential targets for therapy. Our study provides potential diagnostic biomarkers for lung ADC and novel stage‐specific drug targets for rational intervention.

N-glycosylated SGK196 suppresses the metastasis of basal-like breast cancer cells

SGK196 is a protein O-mannose kinase involved in an indispensable phosphorylation step during laminin-binding glycan synthesis on alpha-dystroglycan (α-DG). However, the function of SGK196 in cancer diseases remains elusive. In the current study, we demonstrated that SGK196 is primarily modified by N-glycosylation in breast cancer (BC) cells. Furthermore, gain and loss-of-function studies showed that N-glycosylated SGK196 suppresses cell migration, invasion, and metastasis in BC, particularly in the basal-like breast cancer (BLBC) type. In addition, we found that SGK196 N-glycosylation performs the regulatory function through the PI3K/AKT/GSK3β signaling pathway. Collectively, our results show that N-glycosylated SGK196 plays suppression roles in BLBC metastases, therefore providing new insights into SGK196 function in BC.

The effects and mechanisms of a biosynthetic ginsenoside 3β,12β-Di-O-Glc-PPD on non-small cell lung cancer

Background

A biosynthetic ginsenoside, 3-O-β-D-glucopyranosyl-12-O-β-D-glucopyranosyl-dammar-24-ene-3β, 12β, 20S-triol (C₃C₁₂PPD), showed antitumor activity against many tumor cells in vitro, especially had better anti-lung cancer activity than Rg3 in vitro and in vivo. However, the effects and molecular mechanisms of C₃C₁₂PPD on non-small cell lung cancer (NSCLC) remain unclear. According to previous studies, we hypothesized ginsenoside C₃C₁₂PPD could inhibit the tumor growth of NSCLC by targeting proliferation, migration and angiogenesis.

Methods

A thiazolyl blue tetrazolium bromide assay (MTT) was performed to evaluate cell viability. Additionally, Transwell and tube formation assays were conducted to analyze cell migration and angiogenesis. The Lewis and A549 tumor xenograft experiments were also performed to investigate the effects of C₃C₁₂PPD on tumor growth in vivo, Western blotting and IHC assay were performed to analyze protein expression.

Results

C₃C₁₂PPD could effectively inhibit the proliferation and migration of lung cancer cells, and tube formation of EA.hy926 cell. Ginsenoside C₃C₁₂PPD suppressed Lewis and A549 tumor growth in vivo without obvious side effects on body weight and the hematology index. In addition, the Western blot analysis revealed that the effects of C₃C₁₂PPD on lung cancer were mediated by inhibiting Raf/MEK/ERK, AKT/mTOR and AKT/GSK-3β/β-Catenin signaling pathways. Finally, C₃C₁₂PPD could significantly inhibit the proliferation index and vessel number in Lewis xenograft tumors analyzed by IHC.

Conclusion

The results of the present study suggest that ginsenoside C₃C₁₂PPD may serve as a potential therapeutic candidate compound against NSCLC.

Resveratrol inhibits the invasion and metastasis of colon cancer through reversal of epithelial‑ mesenchymal transition via the AKT/GSK‑3β/Snail signaling pathway

The identification of safe and effective drugs that inhibit tumor invasion and metastasis is required to improve the clinical outcome of patients with colon cancer. The present study aimed to investigate the inhibitory effects and possible mechanisms of action of resveratrol against the invasion and metastasis of colon cancer. AKT1-knockdown SW480 and SW620 colon cancer cells were used to detect the effects of resveratrol on cell invasion and metastasis, as well as changes in the expression of epithelial-mesenchymal transition (EMT) markers and serine/threonine kinase (AKT)/glycogen synthase kinase (GSK)-3β/Snail signaling pathway-related molecules in vitro. Furthermore, nude mice were inoculated with SW480 cells in the tail vein to establish an in vivo lung metastasis model of colon cancer, to investigate the effects of resveratrol on lung metastasis in colon cancer. The results revealed that resveratrol treatment and AKT1 knockdown significantly inhibited cell migration and invasion in colon cancer, and markedly increased E-cadherin expression and decreased that of N-cadherin, phospho (p)-AKT1, p-GSK-3β, and Snail in colon cancer both in vitro and in vivo. Furthermore, the effects of resveratrol were significantly weaker in the AKT1-knockdown cells. In conclusion, resveratrol may suppress the invasion and metastasis of colon cancer through reversal of EMT via the AKT/GSK-3β/Snail signaling pathway. AKT1 may therefore be a key regulator of EMT in colon cancer cells and a potential therapeutic target for this disease.

Matching tRNA modifications in humans to their known and predicted enzymes

tRNA are post-transcriptionally modified by chemical modifications that affect all aspects of tRNA biology. An increasing number of mutations underlying human genetic diseases map to genes encoding for tRNA modification enzymes. However, our knowledge on human tRNA-modification genes remains fragmentary and the most comprehensive RNA modification database currently contains information on approximately 20% of human cytosolic tRNAs, primarily based on biochemical studies. Recent high-throughput methods such as DM-tRNA-seq now allow annotation of a majority of tRNAs for six specific base modifications. Furthermore, we identified large gaps in knowledge when we predicted all cytosolic and mitochondrial human tRNA modification genes. Only 48% of the candidate cytosolic tRNA modification enzymes have been experimentally validated in mammals (either directly or in a heterologous system). Approximately 23% of the modification genes (cytosolic and mitochondrial combined) remain unknown. We discuss these 'unidentified enzymes' cases in detail and propose candidates whenever possible. Finally, tissue-specific expression analysis shows that modification genes are highly expressed in proliferative tissues like testis and transformed cells, but scarcely in differentiated tissues, with the exception of the cerebellum. Our work provides a comprehensive up to date compilation of human tRNA modifications and their enzymes that can be used as a resource for further studies.

Epithelial mesenchymal transition Transcription Factor (TF): The structure, function and microRNA feedback loop

Epithelial to mesenchymal transition (EMT) is a phenomenon in which epithelial cells lose their cell to cell adhesion and detach from the base of the membrane. EMT is a fundamental process which occurs during tumor progression and metastasis. Cancer genomics is a complex network which involves a variety of factors such as transcription factors (TFs), coding genes and microRNAs (miRs). Both TFs and miRs are trans-regulatory elements that crosstalk. Due to a wide range of targets, TF-miR interaction provides a feedback or feedforward loop and cross-gene regulation consequently. In this review, we focused on the structure and function of two TF families involved in EMT, zinc finger and β helix loop helix and p53. Subsequently we analyzed recent findings on TF-miR interaction in EMT.

Cytokeratin 19 (KRT19) has a Role in the Reprogramming of Cancer Stem Cell-Like Cells to Less Aggressive and More Drug-Sensitive Cells

Cytokeratin 19 (KRT19) is a cytoplasmic intermediate filament protein, which is responsible for structural rigidity and multipurpose scaffolds. In several cancers, KRT19 is overexpressed and may play a crucial role in tumorigenic transformation. In our previous study, we revealed the role of KRT19 as signaling component which mediated Wnt/NOTCH crosstalk through NUMB transcription in breast cancer. Here, we investigated the function of KRT19 in cancer reprogramming and drug resistance in breast cancer cells. We found that expression of KRT19 was attenuated in several patients-derived breast cancer tissues and patients with a low expression of KRT19 were significantly correlated with poor prognosis in breast cancer patients. Consistently, highly aggressive and drug-resistant breast cancer patient-derived cancer stem cell-like cells (konkuk university-cancer stem cell-like cell (KU-CSLCs)) displayed higher expression of cancer stem cell (CSC) markers, including ALDH1, CXCR4, and CD133, but a much lower expression of KRT19 than that is seen in highly aggressive triple negative breast cancer MDA-MB231 cells. Moreover, we revealed that the knockdown of KRT19 in MDA-MB231 cells led to an enhancement of cancer properties, such as cell proliferation, sphere formation, migration, and drug resistance, while the overexpression of KRT19 in KU-CSLCs resulted in the significant attenuation of cancer properties. KRT19 regulated cancer stem cell reprogramming by modulating the expression of cancer stem cell markers (ALDH1, CXCR4, and CD133), as well as the phosphorylation of Src and GSK3β (Tyr216). Therefore, our data may imply that the modulation of KRT19 expression could be involved in cancer stem cell reprogramming and drug sensitivity, which might have clinical implications for cancer or cancer stem cell treatment.

Profiling Cytidine Acetylation with Specific Affinity and Reactivity

The human acetyltransferase NAT10 has recently been shown to catalyze formation of N4-acetylcytidine (ac4C), a minor nucleobase known to alter RNA structure and function. In order to better understand the role of RNA acetyltransferases in biology and disease, here we report the development and application of chemical methods to study ac4C. First, we demonstrate that ac4C can be conjugated to carrier proteins using optimized protocols. Next, we describe methods to access ac4C-containing RNAs, enabling the screening of anti-ac4C antibodies. Finally, we validate the specificity of an optimized ac4C affinity reagent in the context of cellular RNA by demonstrating its ability to accurately report on chemical deacetylation of ac4C. Overall, these studies provide a powerful new tool for studying ac4C in biological contexts, as well as new insights into the stability and half-life of this highly conserved RNA modification. More broadly, they demonstrate how chemical reactivity may be exploited to aid the development and validation of nucleobase-targeting affinity reagents designed to target the emerging epitranscriptome.

Clinical significance and biological function of fucosyltransferase 2 in lung adenocarcinoma

Fucosylation, which is catalyzed by fucosyltransferases (FUTs), is one of the most important glycosylation events involved in cancer. Studies have shown that fucosyltransferase 8 (FUT8) is overexpressed in NSCLC and promotes lung cancer progression. However, there are no reports about the pathological role of fucosyltransferase 2 (FUT2) in lung cancer. To identify FUT2 associated with lung cancer, the expression and clinical significance of FUT2 in lung cancer was investigated by Real-Time PCR, Immunohistochemistry and Western Blot. In addition, we investigated the effect of knockdown FUT2 in lung adenocarcinoma cells. The results showed that the expression of FUT2 in lung adenocarcinoma is higher than that in adjacent noncancerous tissues. Knocking down FUT2 in A549 and H1299 cells decreased cell proliferation, migration and invasion, and increased cell apoptosis compared to corresponding control cells. Furthermore, Western Blot showed that knockdown FUT2 can impact the expression of migration-associated and apoptosis-associated proteins in A549 cells. Our results suggest that FUT2 may be associated with lung adenocarcinoma development and thus is a potential biomarker or/and therapeutic target in lung adenocarcinoma.

[CK2α Regulates the Metastases and Migration of Lung Adenocarcinoma A549 Cell Line through PI3K/Akt/GSK-3β Signal Pathway]

背景与目的

肺癌已成为全球癌症死亡的首要原因，而侵袭和转移是导致肿瘤死亡的主要原因之一，蛋白激酶CK2是一种高度保守信使非依赖性丝氨酸苏氨酸蛋白激酶，其在各种肿瘤中高表达。本研究旨在探讨下调CK2α基因表达对肺腺癌A549细胞侵袭迁移的影响以及可能的机制。

方法

构建pSilencer^TM 4.1-shCK2α-eGFP慢病毒表达载体，建立稳定干扰CK2α表达的A549细胞株。利用Transwell和Boyden小室实验检测干扰CK2α表达前后A549细胞的侵袭及迁移的能力。Western blot检测PI3K/Akt信号通路和上皮-间充质转化（mesenchymal-to-epithelial transition, EMT）相关蛋白的表达。

结果

与对照组相比，干扰CK2α表达后肺腺癌A549细胞的侵袭及迁移能力明显下降，p-PTEN、Akt、p-Akt⁴⁷³、p-Akt³⁰⁸、p-PDK1、p-c-Raf、p-GSK-3β蛋白明显下调，PTEN蛋白表达水平显著上调。上皮-间充质转化的相关蛋白E-cadherin蛋白表达水平显著上调，而Vimentin、β-catenin、Snail蛋白表达水平显著下调，与侵袭转移相关蛋白的MMP2、MMP9表达水平显著下调。

结论

CK2α可能通过PI3K/Akt/GSK-3β/Snail信号通路来调控上皮-间充质转化参与肺腺癌A549细胞的侵袭及迁移。