ING5 suppresses proliferation, apoptosis, migration and invasion, and induces autophagy and differentiation of gastric cancer cells: a good marker for carcinogenesis and subsequent progression

Autophagy-driven regulation of cisplatin response in human cancers: Exploring molecular and cell death dynamics

Despite the challenges posed by drug resistance and side effects, chemotherapy remains a pivotal strategy in cancer treatment. A key issue in this context is macroautophagy (commonly known as autophagy), a dysregulated cell death mechanism often observed during chemotherapy. Autophagy plays a cytoprotective role by maintaining cellular homeostasis and recycling organelles, and emerging evidence points to its significant role in promoting cancer progression. Cisplatin, a DNA-intercalating agent known for inducing cell death and cell cycle arrest, often encounters resistance in chemotherapy treatments. Recent studies have shown that autophagy can contribute to cisplatin resistance or insensitivity in tumor cells through various mechanisms. This resistance can be mediated by protective autophagy, which suppresses apoptosis. Additionally, autophagy-related changes in tumor cell metastasis, particularly the induction of Epithelial-Mesenchymal Transition (EMT), can also lead to cisplatin resistance. Nevertheless, pharmacological strategies targeting the regulation of autophagy and apoptosis offer promising avenues to enhance cisplatin sensitivity in cancer therapy. Notably, numerous non-coding RNAs have been identified as regulators of autophagy in the context of cisplatin chemotherapy. Thus, therapeutic targeting of autophagy or its associated pathways holds potential for restoring cisplatin sensitivity, highlighting an important direction for future clinical research.

FAM64A aggravates proliferation, invasion, lipid droplet formation, and chemoresistance in gastric cancer: A biomarker for aggressiveness and a gene therapy target

FAM64A is a mitogen-induced regulator of the metaphase and anaphase transition. Here, we found that FAM64A messenger RNA (mRNA) and protein expression levels were higher in gastric cancer tissue than in normal mucosa (p < .05). FAM64A methylation was negatively correlated with FAM64A mRNA expression (p < .05). The differentially expressed genes of FAM64A were mainly involved in digestion, potassium transporting or exchanging ATPase, contractile fibers, endopeptidase, and pancreatic secretion (p < .05). The FAM64A-related genes were principally categorized into ubiquitin-mediated proteolysis, cell cycle, chromosome segregation and mitosis, microtubule binding and organization, metabolism of amino acids, cytokine receptors, lipid droplet, central nervous system, and collagen trimer (p < .05). FAM64A protein expression was lower in normal gastric mucosa than intestinal metaplasia, adenoma, and primary cancer (p < .05), negatively correlated with older age, T stage, lymphatic and venous invasion, tumor, node, metastasis stage, and dedifferentiation (p < .05), and associated with a favorable overall survival of gastric cancer patients. FAM64A overexpression promoted proliferation, antiapoptosis, migration, invasion, and epithelial-mesenchymal transition via the EGFR/Akt/mTOR/NF-κB, while the opposite effect was observed for FAM64A knockdown. FAM64A also induced chemoresistance directly or indirectly through lipid droplet formation via ING5. These results suggested that upregulation of FAM64A expression might induce aggressive phenotypes, leading to gastric carcinogenesis and its subsequent progression. Thus, FAM64A could be regarded as a prognosis biomarker and a target for gene therapy.

An interpretable Alzheimer's disease oligogenic risk score informed by neuroimaging biomarkers improves risk prediction and stratification

Introduction

Stratification of Alzheimer's disease (AD) patients into risk subgroups using Polygenic Risk Scores (PRS) presents novel opportunities for the development of clinical trials and disease-modifying therapies. However, the heterogeneous nature of AD continues to pose significant challenges for the clinical broadscale use of PRS. PRS remains unfit in demonstrating sufficient accuracy in risk prediction, particularly for individuals with mild cognitive impairment (MCI), and in allowing feasible interpretation of specific genes or SNPs contributing to disease risk. We propose adORS, a novel oligogenic risk score for AD, to better predict risk of disease by using an optimized list of relevant genetic risk factors.

Methods

Using whole genome sequencing data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort (n  =  1,545), we selected 20 genes that exhibited the strongest correlations with FDG-PET and AV45-PET, recognized neuroimaging biomarkers that detect functional brain changes in AD. This subset of genes was incorporated into adORS to assess, in comparison to PRS, the prediction accuracy of CN vs. AD classification and MCI conversion prediction, risk stratification of the ADNI cohort, and interpretability of the genetic information included in the scores.

Results

adORS improved AUC scores over PRS in both CN vs. AD classification and MCI conversion prediction. The oligogenic model also refined risk-based stratification, even without the assistance of APOE, thus reflecting the true prevalence rate of the ADNI cohort compared to PRS. Interpretation analysis shows that genes included in adORS, such as ATF6, EFCAB11, ING5, SIK3, and CD46, have been observed in similar neurodegenerative disorders and/or are supported by AD-related literature.

Discussion

Compared to conventional PRS, adORS may prove to be a more appropriate choice of differentiating patients into high or low genetic risk of AD in clinical studies or settings. Additionally, the ability to interpret specific genetic information allows the focus to be shifted from general relative risk based on a given population to the information that adORS can provide for a single individual, thus permitting the possibility of personalized treatments for AD.

Insights from a Computational-Based Approach for Analyzing Autophagy Genes across Human Cancers

In the last decade, there has been a boost in autophagy reports due to its role in cancer progression and its association with tumor resistance to treatment. Despite this, many questions remain to be elucidated and explored among the different tumors. Here, we used omics-based cancer datasets to identify autophagy genes as prognostic markers in cancer. We then combined these findings with independent studies to further characterize the clinical significance of these genes in cancer. Our observations highlight the importance of innovative approaches to analyze tumor heterogeneity, potentially affecting the expression of autophagy-related genes with either pro-tumoral or anti-tumoral functions. In silico analysis allowed for identifying three genes (TBC1D12, KERA, and TUBA3D) not previously described as associated with autophagy pathways in cancer. While autophagy-related genes were rarely mutated across human cancers, the expression profiles of these genes allowed the clustering of different cancers into three independent groups. We have also analyzed datasets highlighting the effects of drugs or regulatory RNAs on autophagy. Altogether, these data provide a comprehensive list of targets to further the understanding of autophagy mechanisms in cancer and investigate possible therapeutic targets.

Deacetylation via SIRT2 prevents keratin-mutation-associated injury and keratin aggregation

Keratin (K) and other intermediate filament (IF) protein mutations at conserved arginines disrupt keratin filaments into aggregates and cause human epidermolysis bullosa simplex (EBS; K14-R125C) or predispose to mouse liver injury (K18-R90C). The challenge for more than 70 IF-associated diseases is the lack of clinically utilized IF-targeted therapies. We used high-throughput drug screening to identify compounds that normalized mutation-triggered keratin filament disruption. Parthenolide, a plant sesquiterpene lactone, dramatically reversed keratin filament disruption and protected cells and mice expressing K18-R90C from apoptosis. K18-R90C became hyperacetylated compared with K18-WT and treatment with parthenolide normalized K18 acetylation. Parthenolide upregulated the NAD-dependent SIRT2, and increased SIRT2-keratin association. SIRT2 knockdown or pharmacologic inhibition blocked the parthenolide effect, while site-specific Lys-to-Arg mutation of keratin acetylation sites normalized K18-R90C filaments. Treatment of K18-R90C-expressing cells and mice with nicotinamide mononucleotide had a parthenolide-like protective effect. In 2 human K18 variants that associate with human fatal drug-induced liver injury, parthenolide protected K18-D89H- but not K8-K393R-induced filament disruption and cell death. Importantly, parthenolide normalized K14-R125C-mediated filament disruption in keratinocytes and inhibited dispase-triggered keratinocyte sheet fragmentation and Fas-mediated apoptosis. Therefore, keratin acetylation may provide a novel therapeutic target for some keratin-associated diseases.

In silico analysis prediction of HepTH1-5 as a potential therapeutic agent by targeting tumour suppressor protein networks

Many studies reported that the activation of tumour suppressor protein, p53 induced the human hepcidin expression. However, its expression decreased when p53 was silenced in human hepatoma cells. Contrary to Tilapia hepcidin TH1-5, HepTH1-5 was previously reported to trigger the p53 activation through the molecular docking approach. The INhibitor of Growth (ING) family members are also shown to directly interact with p53 and promote cell cycle arrest, senescence, apoptosis and participate in DNA replication and DNA damage responses to suppress the tumour initiation and progression. However, the interrelation between INGs and HepTH1-5 remains unknown. Therefore, this study aims to identify the mechanism and their protein interactions using in silico approaches. The finding revealed that HepTH1-5 and its ligands had interacted mostly on hotspot residues of ING proteins which involved in histone modifications via acetylation, phosphorylation, and methylation. This proves that HepTH1-5 might implicate in an apoptosis signalling pathway and preserve the protein structure and function of INGs by reducing the perturbation of histone binding upon oxidative stress response. This study would provide theoretical guidance for the design and experimental studies to decipher the role of HepTH1-5 as a potential therapeutic agent for cancer therapy. Communicated by Ramaswamy H. Sarma.

The roles of ING5 in cancer: A tumor suppressor

As a Class II tumor suppressor, ING5 contains nuclear localization signal, plant homeodomain, novel conserved region, and leucine zipper-like domains. ING5 proteins form homodimer into a coil-coil structure, and heterodimers with ING4, histone H3K4me3, histone acetyltransferase (HAT) complex, Tip60, Cyclin A1/CDK2, INCA1 and EBNA3C for the transcription of target genes. The acetylated proteins up-regulated by ING5 are preferentially located in nucleus and act as transcription cofactors, chromatin and DNA binding functions, while those down-regulated by ING5 mostly in cytoplasm and contribute to metabolism. ING5 promotes the autoacetylation of HAT p300, p53, histone H3 and H4 for the transcription of downstream genes (Bax, GADD45, p21, p27 and so forth). Transcriptionally, YY1 and SRF up-regulate ING5 mRNA expression by the interaction of YY1-SRF-p53-ING5 complex with ING5 promoter. Translationally, ING5 is targeted by miR-196, miR-196a, miR-196b-5p, miR-193a-3p, miR-27-3p, miR-200b/200a/429, miR-1307, miR-193, miR-222, miR-331-3p, miR-181b, miR-543 and miR-196-b. ING5 suppresses proliferation, migration, invasion and tumor growth of various cancer cells via the suppression of EGFR/PI3K/Akt, IL-6/STAT3, Akt/NF-κB/NF-κB/MMP-9 or IL-6/CXCL12 pathway. ING5-mediated chemoresistance is closely linked to anti-apoptosis, overexpression of chemoresistant genes, the activation of PI3K/Akt/NF-κB and Wnt/β-catenin signal pathways. Histologically, ING5 abrogation in gastric stem-like and pdx1-positive cells causes gastric dysplasia and cancer, and conditional ING5 knockout in pdx1-positive and gastric chief cells increases MNU-induced gastric carcinogenesis. Intestinal ING5 deletion increases AOM/DSS- induced colorectal carcinogenesis and decreases high-fat-diet weight. The overexpression and nucleocytoplasmic translocation of ING5 are seen during carcinogenesis, and ING5 expression was inversely associated with aggressive behaviors and poor prognosis in a variety of cancers. These findings indicated that ING5 might be used for a molecular marker for carcinogenesis and following progression, and as a target for gene therapy if its chemoresistant function might be ameliorated.

Histone Deacetylase Functions in Gastric Cancer: Therapeutic Target?

Gastric cancer (GC) is one of the most aggressive cancers. Therapeutic treatments are based on surgery combined with chemotherapy using a combination of platinum-based agents. However, at metastatic stages of the disease, survival is extremely low due to late diagnosis and resistance mechanisms to chemotherapies. The development of new classifications has not yet identified new prognostic markers for clinical use. The studies of epigenetic processes highlighted the implication of histone acetylation status, regulated by histone acetyltransferases (HATs) and by histone deacetylases (HDACs), in cancer development. In this way, inhibitors of HDACs (HDACis) have been developed and some of them have already been clinically approved to treat T-cell lymphoma and multiple myeloma. In this review, we summarize the regulations and functions of eighteen HDACs in GC, describing their known targets, involved cellular processes, associated clinicopathological features, and impact on survival of patients. Additionally, we resume the in vitro, pre-clinical, and clinical trials of four HDACis approved by Food and Drug Administration (FDA) in cancers in the context of GC.

Proteomics of Aqueous Humor as a Source of Disease Biomarkers in Retinoblastoma

Aqueous humor (AH) can be easily and safely used to evaluate disease-specific biomarkers in ocular disease. The aim of this study was to identify specific proteins biomarkers in the AH of retinoblastoma (RB) patients at various stages of the disease. We analyzed the proteome of 53 AH samples using high-resolution mass spectrometry. We grouped the samples according to active vitreous seeding (Group 1), active aqueous seeding (Group 2), naive RB (group 3), inactive RB (group 4), and congenital cataracts as the control (Group 5). We found a total of 889 proteins in all samples. Comparative parametric analyses among the different groups revealed three additional proteins expressed in the RB groups that were not expressed in the control group. These were histone H2B type 2-E (HISTH2B2E), InaD-like protein (PATJ), and ubiquitin conjugating enzyme E2 V1 (UBE2V1). Upon processing the data of our study with the OpenTarget Tool software, we found that glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and CD44 were more highly expressed in the RB groups. Our results provide a proteome database regarding AH related to RB disease that may be used as a source of biomarkers. Further prospective studies should validate our finding in a large cohort of RB patients.

Ginsenoside CK, rather than Rb1, possesses potential chemopreventive activities in human gastric cancer via regulating PI3K/AKT/NF-κB signal pathway

Ginsenoside Rb1, a main component of ginseng, is often transformed into ginsenoside CK by intestinal flora to exert various pharmacological activity. However, it remains unclear whether ginsenoside CK is responsible for the anti-gastric cancer effect of ginsenoside Rb1 in vivo. In this study, network pharmacology was applied to predict the key signal pathways of ginsenoside Rb1 and ginsenoside CK when treating gastric cancer. The anti-proliferative effects of ginsenoside Rb1 and ginsenoside CK and the underlying mechanism in gastric cancer cells were explored by MTT, Hoechst3328 staining, ELISA, RT-qPCR and Western blotting. The results showed that PI3K-AKT/NF-κB signal pathway was the common important pathway of ginsenoside Rb1 and CK in the treatment of gastric cancer. The results of MTT assay showed that ginsenoside Rb1 could hardly inhibit the proliferation of HGC-27 cells, whereas ginsenoside CK could inhibit the proliferation of HGC-27 cells. Hoechst3328 staining showed that cells in the ginsenoside CK group were densely stained bright blue and nuclear fragmented, indicating that apoptosis occurred. ELISA results showed that ginsenoside CK could effectively downregulate the levels of cyclin CyclinB1 and CyclinD1, but ginsenoside Rb1 had no significant effect. Also, the results of Western blot and RT-qPCR showed that ginsenoside CK inhibited the expressions of anti-apoptosis-related protein Bcl-2 and apoptosis-related pathway PI3K/AKT/NF-κB, and promoted the expression of pro-apoptosis proteins Bax and Caspase 3, whereas ginsenoside Rb1 exerted no effect. In short, ginsenoside Rb1 had no anti-gastric cancer cell activity in vitro, but ginsenoside CK could effectively inhibit cell proliferation and induce cell apoptosis in HGC-27 cells. The mechanism might relate to the inhibitory effect of ginsenoside CK on the PI3K/AKT/NF-κB pathway. These results suggest that ginsenoside CK might be the in vivo material basis for the anti-gastric cancer activity of ginsenosides.

Molecular mechanisms of inhibitor of growth (ING) family members in health and malignancy

ING genes belong to family of tumor suppressor genes with regulatory functions on cell proliferation, apoptosis, and cellular senescence. These include a family of proteins with 5 members (ING1-5), which are downregulated in human malignancies and/or affected by pathogenic mutations. ING proteins are highly evolutionarily conserved proteins containing several domains through which bind to chromatin structures by exerting their effects as readers of histone modification marks, and also binding to proteins like p53 involved in biological processes such as cell cycle regulation. Further, they are known as subunits of histone acetylation as well as deacetylation complexes and so exert their regulatory roles through epigenetic mechanisms. Playing role in restriction of proliferative but also invasive potentials of normal cells, INGs are particularly involved in cancer development and progression. However, additional studies and experimental confirmation are required for these models. This paper highlights the potential impact that INGs may have on the development of human cancer and explores what new information has recently arise on the functions of ING genes.

CircCOL1A2 Sponges MiR-1286 to Promote Cell Invasion and Migration of Gastric Cancer by Elevating Expression of USP10 to Downregulate RFC2 Ubiquitination Level

Gastric cancers (GC) are generally malignant tumors, occurring with high incidence and threatening public health around the world. Circular RNAs (circRNAs) play crucial roles in modulating various cancers, including GC. However, the functions of circRNAs and their regulatory mechanism in colorectal cancer (CRC) remain largely unknown. This study focuses on both the role of circCOL1A2 in CRC progression as well as its downstream molecular mechanism. Quantitative polymerase chain reaction (qPCR) and western blot were adopted for gene expression analysis. Functional experiments were performed to study the biological functions. Fluorescence in situ hybridization (FISH) and subcellular fraction assays were employed to detect the subcellular distribution. Luciferase reporter, RNA-binding protein immunoprecipitation (RIP), co-immunoprecipitation (Co-IP), RNA pull-down, and immunofluorescence (IF) and immunoprecipitation (IP) assays were used to explore the underlying mechanisms. Our results found circCOL1A2 to be not only upregulated in GC cells, but that it also propels the migration and invasion of GC cells. CircCOL1A2 functions as a competing endogenous RNA (ceRNA) by sequestering microRNA-1286 (miR-1286) to modulate ubiquitin-specific peptidase 10 (USP10), which in turn spurs the migration and invasion of GC cells by regulating RFC2. In sum, CircCOL1A2 sponges miR-1286 to promote cell invasion and migration of GC by elevating the expression of USP10 to downregulate the level of RFC2 ubiquitination. Our study offers a potential novel target for the early diagnosis and treatment of GC.

Transcriptional Regulation of ING5 and its Suppressive Effects on Gastric Cancer

ING5 targets histone acetyltransferase or histone deacetylase complexes for local chromatin remodeling. Its transcriptional regulation and suppressive effects on gastric cancer remain elusive. Luciferase assay, EMSA, and ChIP were used to identify the cis-acting elements and trans-acting factors of the ING5 gene. We analyzed the effects of SAHA on the aggressive phenotypes of ING5 transfectants, and the effects of different ING5 mutants on aggressive phenotypes in SGC-7901 cells. Finally, we observed the effects of ING5 abrogation on gastric carcinogenesis. EMSA and ChIP showed that both SRF (−717 to −678 bp) and YY1 (−48 to 25bp) interacted with the promoter of ING5 and up-regulated ING5 expression in gastric cancer via SRF-YY1-ING5-p53 complex formation. ING5, SRF, and YY1 were overexpressed in gastric cancer, (P<0.05), and associated with worse prognosis of gastric cancer patients (P<0.05). ING5 had positive relationships with SRF and YY1 expression in gastric cancer (P<0.05). SAHA treatment caused early arrest at S phase in ING5 transfectants of SGC-7901 (P<0.05), and either 0.5 or 1.0 μM SAHA enhanced their migration and invasion (P<0.05). The wild-type and mutant ING5 transfectants showed lower viability and invasion than the control (P<0.05) with low CDC25, VEGF, and MMP-9 expression. Gastric spontaneous adenocarcinoma was observed in Atp4b-cre; ING5^f/f, Pdx1-cre; ING5^f/f, and K19-cre; ING5^f/f mice. ING5 deletion increased the sensitivity of MNU-induced gastric carcinogenesis. ING5 mRNA might be a good marker of gastric carcinogenesis, and poor prognosis. ING5 expression was positively regulated by the interaction of SRF-YY1-ING5-p53 complex within the ING5 promoter from −50 bp upstream to the transcription start site. ING5 deletion might contribute to the tumorigenesis and histogenesis of gastric cancer.

ING Tumour Suppressors and ING Splice Variants as Coregulators of the Androgen Receptor Signalling in Prostate Cancer

Prevention and overcoming castration resistance of prostate cancer (PC) remains one of the main unsolved problems in modern oncology. Hence, many studies are focused on the investigation of novel androgen receptor (AR) regulators that could serve as potential drug targets in disease therapy. Among such factors, inhibitor of growth (ING) proteins were identified. Some ING proteins act as AR transcriptional coregulators, indicating their relevance for PC research. The ING family consists of five protein-coding genes from ING1 to ING5 and pseudogene INGX. The ING genes were revealed through their sequence homology to the first identified ING1 from an in vivo screen. ING factors are a part of histone modification complexes. With the help of the conserved plant homeodomain (PHD) motif, ING factors bind to Histone 3 Lysine 4 (H3K4) methylation mark with a stronger affinity to the highest methylation grade H3K4me3 and recruit histone acetyltransferases (HAT) and histone deacetylases (HDAC) to chromatin. ING1 and ING2 are core subunits of mSIN3a-HDAC corepressor complexes, whereas ING3–5 interact with different HAT complexes that serve as coactivators. ING members belong to type II tumour suppressors and are frequently downregulated in many types of malignancies, including PC. As the family name indicates, ING proteins are able to inhibit cell growth and tumour development via regulation of cell cycle and cancer-relevant pathways such as apoptosis, cellular senescence, DNA repair, cell migration, invasion, and angiogenesis. Many ING splice variants that enhance the diversity of ING activity were discovered. However, it seems that the existence of multiple ING splice variants is underestimated, since alternative splice variants, such as the AR coregulators ING1 and ING3, counteract full-length ING and thus play an opposite functional role. These results open a novel prospective investigation direction in understanding ING factors biology in PC and other malignancies.

Glutathione S-Transferase M3 Is Associated with Glycolysis in Intrinsic Temozolomide-Resistant Glioblastoma Multiforme Cells

Glioblastoma multiforme (GBM) is a malignant primary brain tumor. The 5-year relative survival rate of patients with GBM remains <30% on average despite aggressive treatments, and secondary therapy fails in 90% of patients. In chemotherapeutic failure, detoxification proteins are crucial to the activity of chemotherapy drugs. Usually, glutathione S-transferase (GST) superfamily members act as detoxification enzymes by activating xenobiotic metabolites through conjugation with glutathione in healthy cells. However, some overexpressed GSTs not only increase GST activity but also trigger chemotherapy resistance and tumorigenesis-related signaling transductions. Whether GSTM3 is involved in GBM chemoresistance remains unclear. In the current study, we found that T98G, a GBM cell line with pre-existing temozolomide (TMZ) resistance, has high glycolysis and GSTM3 expression. GSTM3 knockdown in T98G decreased glycolysis ability through lactate dehydrogenase A activity reduction. Moreover, it increased TMZ toxicity and decreased invasion ability. Furthermore, we provide next-generation sequencing-based identification of significantly changed messenger RNAs of T98G cells with GSTM3 knockdown for further research. GSTM3 was downregulated in intrinsic TMZ-resistant T98G with a change in the expression levels of some essential glycolysis-related genes. Thus, GSTM3 was associated with glycolysis in chemotherapeutic resistance in T98G cells. Our findings provide new insight into the GSTM3 mechanism in recurring GBM.

Molecular Expression of Some Oncogenes and Predisposing Behaviors Contributing to the Aggressiveness of Prostate Cancer

Background

Prostate cancer is the second most common cancer in men in Iran. It can be treated in the early stages of the disease; therefore, early diagnosis can be lifesaving. The aim of this study was to investigate the molecular expression of some oncogenes and predisposing behaviors contributing to the aggressiveness of prostate cancer.

Methods

In this case-control study, prostate cancer specimens were collected from both patients and healthy volunteers. Several factors such as age, family history, smoking, and stage of the disease, were investigated based on the criteria of this study. Real-time PCR was used to measure the expression of four oncogenes. Statistical analysis of our data was carried out using SPSS software version 22.

Results

The X² test showed that there was a difference in the incidence of prostate cancer in different age groups (X²= 9.30; p= 0.026). Although data analysis by the X² test showed that family history had a significant effect on prostate cancer (X²= 14.43; p= 0.001), smoking did not show a significant effect on the incidence of this disorder (X²= 4.67; p= 0.097). The T2N1M0 stage is the most common form of prostate cancer in patients with family history of prostate cancer and the habit of smoking. Also, the expression of KRAS1P, GLB1L2, SChLAP1 and PACSIN3 oncogenes reduced in prostate cancer samples compared to the control group.

Conclusion

Overall, functional interpretation of gene expression in the prostate tissue can affect tumor progression. Yet, further practical studies are required to reveal the accurate underlying mechanisms.

MicroRNA-196b-5p promotes malignant progression of colorectal cancer by targeting ING5

Background

miR-196b-5p expression is deregulated in many malignant tumors. Although miR-196b-5p has been implicated in the malignant transformation of colorectal cancer, its role in this specific type of cancer has not been fully explored. Thus, the present study was aimed to examine the cellular function of miR-196b-5p and its role in malignant biological behavior in colorectal cancer.

Methods

miR-196b-5p expression was measured in colorectal cancer tissues and cell lines using quantitative real-time PCR. Cell counting kit-8 (CCK-8) assay and Transwell assay were used to detect proliferation, migration, and invasion in cell lines, whereas flow cytometry was applied to study apoptosis. Western blot analysis was performed to measure the protein levels. Dual luciferase reporter assay was used to investigate the interaction between miR-196b-5p and ING5. Tumor formation was evaluated in mice.

Results

MiR-196b-5p was abundantly expressed in colorectal cancer tissues and cell lines, whereas ING5 was expressed at low levels. MiR-196b-5p was successfully overexpressed or knocked down in colorectal cancer cells. We found that miR-196b-5p overexpression significantly accelerated the proliferation, cell cycle, migration and invasion, while inhibited cell apoptosis in colorectal cancer cells. However, miR-196b-5p inhibitor showed the opposite effects. Moreover, ING5 overexpression or knockdown was successfully performed in colorectal cancer cells. ING5 overexpression suppressed proliferation, migration, invasion, the phosphorylation of PI3K, Akt as well as MEK, and promoted cell apoptosis, which could be reversed by ING5 knockdown. Additionally, ING5 was identified as a target of miR-196b-5p through bioinformatics analysis and a luciferase activity assay. Furthermore, ING5 knockdown could attenuate the decrease in proliferation, migration, invasion, and the protein levels of p-PI3K, p-Akt, and p-MEK, which were induced by miRNA-196b-5p inhibitor. Besides, miR-196b-5p knockdown inhibited tumor growth, whereas ING5 knockdown elevated it in vivo.

Conclusions

In conclusion, miR-196b-5p promotes cell proliferation, migration, invasion, and inhibits apoptosis in colorectal cancer by targeting ING5.

ING5 inhibits cancer aggressiveness by inhibiting Akt and activating p53 in prostate cancer

Prostate cancer (PCa) is one of the most common types of cancer in men. In several recent studies, chromosomal deletions in the q arm of chromosome 2, where ING5 resides within, have been identified in various cancer types including PCa. In this study, we investigate the role of ING5 as a tumor suppressor in PCa. We examined the expression level of ING5 in tissue samples and cell lines using quantitative real-time polymerase chain reaction and western blot analysis. We tested the in vitro tumor suppressor potential of ING5 in PC3 and LNCaP cells stably overexpressing it using cell viability, colony formation, migration, invasion, and apoptosis assays. We then investigated the effects of ING5 on the Akt and p53 signaling using western blot analysis. We show that ING5 is significantly downregulated in PCa tumor tissue samples and cell lines compared with the corresponding controls. In vitro assays demonstrate that ING5 effectively suppresses proliferative, clonogenic, migratory, and invasive potential and induce apoptosis in PCa cells. ING5 may potentially exert its anti-tumor potential by inhibiting AKT and inducing p53 signaling pathways. Our findings demonstrate that ING5 possesses tumor suppressor roles in vitro, pointing its importance during the prostatic carcinogenesis processes.

Autophagy Attenuation Hampers Progesterone Synthesis during the Development of Pregnant Corpus Luteum

Simple Summary

The present study demonstrates that induction of autophagy-related proteins in corpus luteum is regulated by Akt/mTOR signaling and autophagy may exert influences on progesterone production by controlling the pool of lipid droplets in luteal cells during the luteal development of pregnant rats. Furthermore, mitophagy-related proteins were also induced during the initiation of luteal regression in pregnant rats, which may play an essential role in the maintenance of mitochondrial homeostasis. These findings will shed light on the role of autophagy during the luteal development of pregnant ovaries in vivo in mammals.

Abstract

The contribution of autophagy to catabolic balance has been well-established in various types of cells, whereas the involvement of autophagy in progesterone synthesis during rat pregnancy still remains unknown. Therefore, the present study was designed to evaluate the role of autophagy in progesterone production during the luteal development of pregnant rats. The results showed autophagy-related proteins was maintained at a low level on day 10 after pregnancy, significantly induced on day 16 and subsided to a relative low level on day 21, which was consistent with the changes of serum progesterone levels. The findings further indicated the contribution of autophagy to progesterone production was regulated by inactivation of Akt/mTOR signaling during the luteal development of pregnant rats in in vivo and in vitro experiments. Further investigations revealed autophagy may be involved in the surge of progesterone production in pregnant rats, as inhibition of autophagy by 3-MA compromised serum progesterone levels. Furthermore, 3-MA treatment also leveled down the number of lipid droplets in luteal cells, implying that autophagy may affect the production of progesterone by manipulating the formation of lipid droplets in luteal cells. In addition, the results suggested that mitophagy was mobilized during the primary stage of luteolysis and inhibition of autophagy promoted the increase of redundant mitochondrial and cytoplasmic cytochrome C in luteal cells of pregnant rats. Taken together, the present study indicated that autophagy-related proteins were induced by the inactivation of Akt/mTOR signaling and then contributed to the progesterone production possibly by affecting the formation of intracellular lipid droplets during the luteal development of pregnant rats. To our knowledge, this will provide a new insight into the important mechanism of autophagy regulating progesterone production in ovaries of pregnant mammals.

Upregulation of miR-376c-3p alleviates oxygen-glucose deprivation-induced cell injury by targeting ING5

Background

The expression level of miR-376c-3p is significantly lower in infants with neonatal hypoxic-ischemic encephalopathy (HIE) than in healthy infants. However, the biological function of this microRNA remains largely elusive.

Methods

We used PC-12 and SH-SY5Y cells to establish an oxygen–glucose deprivation (OGD) cell injury model to mimic HIE in vitro. The miR-376c-3p expression levels were measured using quantitative reverse transcription PCR. The CCK-8 assay and flow cytometry were utilized to evaluate OGD-induced cell injury. The association between miR-376c-3p and inhibitor of growth 5 (ING5) was validated using the luciferase reporter assay. Western blotting was conducted to determine the protein expression of CDK4, cyclin D1, Bcl-2 and Bax.

Results

MiR-376c-3p was significantly downregulated in the OGD-induced cell injury model. Its overexpression elevated cell viability and impaired cell cycle G0/G1 phase arrest and apoptosis in PC-12 and SH-SY5Y cells after OGD. Downregulation of miR-376c-3p gave the opposite results. We further demonstrated that ING5 was a negatively regulated target gene of miR-376c-3p. Importantly, ING5 knockdown had a similar effect to miR-376c-3p-mediated protective effects against cell injury induced by OGD. Its overexpression abolished these protective effects.

Conclusion

Our data suggest that miR-376c-3p downregulated ING5 to exert protective effects against OGD-induced cell injury in PC-12 and SH-SY5Y cells. This might represent a novel therapeutic approach for neonatal HIE treatment.

Replication-dependent histone isoforms: a new source of complexity in chromatin structure and function

Replication-dependent histones are expressed in a cell cycle regulated manner and supply the histones necessary to support DNA replication. In mammals, the replication-dependent histones are encoded by a family of genes that are located in several clusters. In humans, these include 16 genes for histone H2A, 22 genes for histone H2B, 14 genes for histone H3, 14 genes for histone H4 and 6 genes for histone H1. While the proteins encoded by these genes are highly similar, they are not identical. For many years, these genes were thought to encode functionally equivalent histone proteins. However, several lines of evidence have emerged that suggest that the replication-dependent histone genes can have specific functions and may constitute a novel layer of chromatin regulation. This Survey and Summary reviews the literature on replication-dependent histone isoforms and discusses potential mechanisms by which the small variations in primary sequence between the isoforms can alter chromatin function. In addition, we summarize the wealth of data implicating altered regulation of histone isoform expression in cancer.

ING5 inhibits lung cancer invasion and epithelial-mesenchymal transition by inhibiting the WNT/β-catenin pathway

Background

ING5 is the last member of the Inhibitor of Growth (ING) candidate tumor suppressor family that has been implicated in multiple cellular functions, including cell cycle regulation, apoptosis, and chromatin remodeling. Our previous study showed that ING5 overexpression inhibits lung cancer aggressiveness and epithelial–mesenchymal transition (EMT), with unknown mechanisms.

Methods

Western blotting was used to detect total and phosphorylated levels of β‐catenin and EMT‐related proteins. Immunofluorescent staining was used to observe E‐cadherin expression. Proliferation and colony formation, wound healing, and Transwell migration and invasion assays were performed to study the proliferative and invasive abilities of cancer cells.

Results

ING5 overexpression promotes phosphorylation of β‐catenin at Ser33/37, leading to a decreased β‐catenin protein level. Small hairpin RNA‐mediated ING5 knockdown significantly increased the β‐catenin level and inhibited phosphorylation of β‐catenin S33/37. Treatment with the WNT/β‐catenin inhibitor XAV939 inhibited ING5‐knockdown promoted proliferation, colony formation, migration, and invasion of lung cancer A549 cells, with increased phosphorylation of β‐catenin S33/37 and a decreased β‐catenin level. XAV939 also impaired ING5‐knockdown‐induced EMT, as indicated by upregulated expression of the EMT marker E‐cadherin, an epithelial marker; and decreased expression of N‐cadherin, a mesenchymal marker, and EMT‐related transcription factors, including Snail, Slug, Twist, and Smad3. Furthermore, XAV939 could inhibit the activation of both IL‐6/STAT3 and PI3K/Akt signaling pathways.

Conclusion

ING5 inhibits lung cancer invasion and EMT by inhibiting the WNT/β‐catenin pathway.

Constitutive activation of Notch2 signalling confers chemoresistance to neural stem cells via transactivation of fibroblast growth factor receptor-1

Notch signalling regulates neural stem cell (NSC) proliferation, differentiation and survival for the correct development and functioning of the central nervous system. Overactive Notch2 signalling has been associated with poor prognosis of aggressive brain tumours, such as glioblastoma multiforme (GBM). We recently reported that constitutive expression of the Notch2 intracellular domain (N2ICD) enhances proliferation and gliogenesis in NSCs. Here, we investigated the mechanism by which Notch2 promotes resistance to apoptosis of NSCs to cytotoxic insults. We performed ex vivo studies using NSC cultures from transgenic mice constitutively expressing N2ICD. These NSCs expressed increased levels of pro-survival factors and lack an apoptotic response to the topoisomerase inhibitor etoposide, not showing neither mitochondrial damage nor caspase activation. Interestingly, Notch2 signalling also regulated chemoresistance of human GBM cells to etoposide. We also identified a signalling crosstalk with FGF signalling pathway involved in this resistance to apoptosis of NSCs. Aberrant Notch2 expression enhances fibroblast growth factor receptor-1 (FGFR1) activity to specifically target the AKT-GSK3 signalling pathway to block apoptosis. These results have implications for understanding molecular changes involved in both tumorigenesis and therapy resistance.

Regulat-INGs in tumors and diseases: Focus on ncRNAs

ING family genes (Inhibitor of Growth) are tumor suppressor genes that play a vital role in cell homeostasis. It has been shown that their expression is lost or diminished in many cancers and other diseases. The main mechanisms by which they are regulated in oncogenesis have not yet been fully elucidated. The involvement of non-coding RNAs (ncRNAs) and in particular microRNAs (miRNAs) in post-transcriptional gene regulation is well established. miRNAs are short sequences (18-25 nucleotides) that can bind to the 3 'UTR sequence of the targeted messenger RNA (mRNA), leading to its degradation or translational repression. Interactions between the ING family and miRNAs have been described in some cancers but also in other diseases. The involvement of miRNAs in ING family regulation opens up new fields of investigation, particularly for targeted therapies. In this review, we will summarize the regulatory mechanisms at the RNA and protein level of the ING family and focus on the interactions with ncRNAs.

ING5 is a Potential Target for Osteosarcoma Therapy

Osteosarcoma is one of the most common primary malignant bone tumors. The inhibitor of growth family of protein 5 has been identified as a tumor suppressor in many cancers. In this study, we confirmed the downregulation of the both inhibitor of growth family of protein 5 and messenger RNA levels in cancer tissues using Western blot and real-time polymerase chain reaction. In order to find the antitumor roles of inhibitor of growth family of protein 5, osteosarcoma cells, HOS, and MG63 were transfected with the plasmid pCDNA-3.1-inhibitor of growth family of protein 5. Overexpression of Inhibitor of growth family of protein 5 could induce apoptosis and inhibit cell proliferation in osteosarcoma cells. Furthermore, Western blot analysis showed that p-Smad2, p-Smad3, and Smad4 were increased in inhibitor of growth family of protein 5-expressing osteosarcoma cells. Our results indicated that overexpression of inhibitor of growth family of protein 5 in osteosarcoma cells induces apoptosis by activating the Smad pathway, thus proposing a promising role for inhibitor of growth family of protein 5 in treatment of patients with osteosarcoma.

Long noncoding RNA UCA1 promotes the proliferation of hypoxic human pulmonary artery smooth muscle cells

Our study explored the effects of lncRNA UCA1 on the proliferation and apoptosis in hypoxic human pulmonary artery smooth muscle cells (HPASMCs) and highlighted the endogenous relationship between UCA1, ING5, and hnRNP I in cell proliferation. Hypoxia-induced HPASMCs were used to simulate pulmonary arterial hypertension in vitro. Microarray assay was adopted to screen the dysregulated expressed lncRNAs in HPASMCs to find out the target gene of our study. And RT-qPCR was performed to detect the expression of lncRNA UCA1 under hypoxia and normoxia. After transfection, the relationship between UCA1 and cell proliferation in HPASMCs under hypoxia were determined by cell proliferation assay and relative expression of PCNA. Next, ELISA assays were conducted to measure the protein levels of PCNA and ING5. What's more, flow cytometry was employed to measure the apoptosis rate in differentially UCA1-expressed HPASMCs. RIP assays were conducted to further clarify the endogenous relationship between UCA1 and ING5 in hypoxic HPASMCs. Finally, the effects of ING5 to HPASMCs were detected after transfection of ING5 and UCA1 to figure out the role of ING5 in HPASMCs. Hypoxia was revealed to induce proliferation and inhibited apoptosis in HPASMCs. Besides, UCA1 was confirmed to be highly expressed under hypoxia compared with normoxia. UCA1 boosted cell proliferation under hypoxia in HPASMCs. However, the apoptosis was suppressed in the hypoxic HPASMCs transfected with pcDNA3.1-UCA1. Further, mechanism studies found that UCA1 competed with ING5 for hnRNP I, so that upregulating UCA1 inhibited the protein levels of ING5. And finally we found that ING5 restrained cell viability, but promoted cell apoptosis in hypoxic HPASMCs, which was reversed by UCA1 over-expression. In summary, our findings manifested that UCA1 promoted proliferation and restrained apoptosis by competing with ING5 for hnRNP I in HPASMCs induced by hypoxia, indicating their potential roles for the cure of hypoxic pulmonary hypertension.

Inhibition of lysyl oxidase expression by dextran sulfate affects invasion and migration of gastric cancer cells

In the present study, the effect of dextran sulfate (DS) on the metastasis and invasion of human gastric cancer cells and its key underlying mechanism were investigated. The levels of hypoxia‑inducible factor 1α (HIF‑1α), transforming growth factor β (TGF‑β) and lysyl oxidase (LOX) expression were evaluated in human gastric cancer and peritumoral tissues by immunohistochemical analysis. Cell proliferation and apoptosis were also examined using the Cell Counting Kit‑8 assay and flow cytometry. The effect of DS on the invasion and migration of BGC‑823 cells was assessed using a Transwell assay. BGC‑823 cells were divided into the control (phosphate‑buffered saline‑treated) and experimental (DS‑treated) groups, and cultured for different times under hypoxic conditions. Subsequently, LOX and TGF‑β expression levels in the cells were measured by immunocytochemistry, immunofluorescence, reverse transcription‑quantitative polymerase chain reaction and western blot analysis. HIF‑1α, TGF‑β and LOX expression levels were significantly higher in human gastric cancer tissues as compared with that in adjacent tissues. DS influenced cell proliferation and apoptosis in a dose‑dependent manner. Furthermore, DS reduced the number of invaded and migrated cells. Under hypoxic conditions, DS reduced HIF‑1α, TGF‑β and LOX expression levels in BGC‑823 cells. After 12 h, the effect of combination of DS and β‑aminopropionitrile (BAPN) on LOX and TGF‑β protein levels was more significant compared with that of DS or BAPN alone. Therefore, DS may inhibit the invasion and migration of human gastric cancer cells under hypoxic conditions by influencing LOX.

ING5-mediated antineuroblastoma effects of suberoylanilide hydroxamic acid

Neuroblastoma is the most common extracranial solid neuroendocrine cancer and is one of the leading causes of death in children. To improve clinical outcomes and prognosis, discovering new promising drugs and targeted medicine is essential. We found that applying Suberoylanilide hydroxamic acid (SAHA; Vorinostat, a histone deacetylase inhibitor) and MG132 (a proteasome inhibitor) to SH‐SY5Y cells synergistically suppressed proliferation, glucose metabolism, migration, and invasion and induced apoptosis and cell cycle arrest. These effects occurred both concentration and time dependently and were associated with the effects observed with inhibitor of growth 5 (ING5) overexpression. SAHA and MG132 treatment increased the expression levels of ING5, PTEN, p53, Caspase‐3, Bax, p21, and p27 but decreased the expression levels of 14‐3‐3, MMP‐2, MMP‐9, ADFP, Nanog, c‐myc, CyclinD1, CyclinB1, and Cdc25c concentration dependently, similar to ING5. SAHA may downregulate miR‐543 and miR‐196‐b expression to enhance the translation of ING5 protein, which promotes acetylation of histones H3 and H4. All three proteins (ING5 and acetylated histones H3 and H4) were recruited to the promoters of c‐myc, Nanog, CyclinD1, p21, and p27 for complex formation, thereby regulating the mRNA expression of downstream genes. ING5 overexpression and SAHA and/or MG132 administration inhibited tumor growth in SH‐SY5Y cells by suppressing proliferation and inducing apoptosis. The expression of acetylated histones H3 and ING5 may be closely linked to the tumor size of neuroblastomas. In summary, SAHA and/or MG132 can synergistically suppress the malignant phenotypes of neuroblastoma cells through the miRNA‐ING5‐histone acetylation axis and via proteasomal degradation, respectively. Therefore, the two drugs may serve as potential treatments for neuroblastoma.

Potential role of chromatin remodeling factor genes in atrophic gastritis/gastric cancer risk

BACKGROUND/AIMS

Atrophic gastritis (AG), intestinal metaplasia (IM), and Helicobacter pylori (HP) are the risk factors for the development of gastric cancer (GC). Chromatin remodeling is one of the epigenetic mechanisms involved in the carcinogenesis of GC. The purpose of this study was to investigate the expression profiles of defined chromatin remodeling genes in gastric mucosal samples and their values as gastric carcinogenesis biomarkers.

MATERIALS AND METHODS

In total, 95 patients were included in the study. Patients were divided into 3 groups as: GC group (n=34), AG group (n=36), and control group (n=25). AG group was further divided into subgroups based on the presence of HP and IM in gastric mucosa. Chromatin remodeling gene expressions were analyzed using real-time PCR (RT-PCR) array in all groups. Data were evaluated using the RT-qPCR primer assay data analysis software.

RESULTS

EED, CBX3, and MTA1 were more overexpressed, whereas ARID1A, ING5, and CBX7 were more underexpressed in the AG and GC groups compared with the controls. No significant differences were observed between the AG and GC groups concerning the expression of these 6 genes, although the fold change levels of these genes in the GC group were well above than in the AG group. EED, CBX3, and MTA1 were significantly more overexpressed in HP- and IM-positive AG subgroup compared with the HP- or IM-negative AG subgroup.

CONCLUSION

In conclusion, our results provide an evidence of epigenetic alterations in AG. Expressions of EED, CBX3, MTA1, ARID1A, ING5, and CBX7 may be considered as promising markers to be used in GC screening for patients with AG.

The down-regulated ING5 expression in lung cancer: a potential target of gene therapy

ING5 can interact with p53, thereby inhibiting cell growth and inducing apoptosis. We found that ING5 overexpression not only inhibited proliferation, migration, and invasion, but also induced G2 arrest, differentiation, autophagy, apoptosis, glycolysis and mitochondrial respiration in lung cancer cells. ING5 transfection up-regulated the expression of Cdc2, ATG13, ATG14, Beclin-1, LC-3B, AIF, cytochrome c, Akt1/2/3, ADFP, PFK-1 and PDPc, while down-regulated the expression of Bcl-2, XIAP, survivin,β-catenin and HXK1. ING5 transfection desensitized cells to the chemotherapy of MG132, paclitaxel, and SAHA, which paralleled with apoptotic alteration. ING5 overexpression suppressed the xenograft tumor growth by inhibiting proliferation and inducing apoptosis. ING5 expression level was significantly higher in normal tissue than that in lung cancer at both protein and mRNA levels. Nuclear ING5 expression was positively correlated with ki-67 expression and cytoplasmic ING5 expression. Cytoplasmic ING5 expression was positively associated with lymph node metastasis, and negatively with age, lymphatic invasion or CPP32 expression. ING5 expression was different in histological classification: squamous cell carcinoma > adenocarcinoma > large cell carcinoma > small cell carcinoma. Taken together, our data suggested that ING5 downregulation might involved in carcinogenesis, growth, and invasion of lung cancer and could be considered as a promising marker to gauge the aggressiveness of lung cancer. It might be employed as a potential target for gene therapy of lung cancer.

Multi-kinase inhibitors interact with sildenafil and ERBB1/2/4 inhibitors to kill tumor cells in vitro and in vivo

We have recently demonstrated that multi-kinase inhibitors such as sorafenib and pazopanib can suppress the detection of chaperones by in situ immuno-fluorescence, which is further enhanced by phosphodiesterase 5 inhibitors. Sorafenib and pazopanib inhibited the HSP90 ATPase activity with IC50 values of ~1.0 μM and ~75 nM, respectively. Pazopanib docked in silico with two possible poses into the HSP90 ATP binding pocket. Pazopanib and sildenafil combined to reduce the total protein levels of HSP1H/p105 and c-MYC and to reduce their co-localization. Sorafenib/pazopanib combined with sildenafil in a [GRP78+HSP27] –dependent fashion to: (i) profoundly activate an eIF2α/Beclin1 pathway; (ii) profoundly inactivate mTOR and increase ATG13 phosphorylation, collectively resulting in the formation of toxic autophagosomes. In a fresh PDX isolate of NSCLC combined knock down of [ERBB1+ERBB3] or use of the ERBB1/2/4 inhibitor afatinib altered cell morphology, enhanced ATG13 phosphorylation, inactivated NFκB, and further enhanced [sorafenib/pazopanib + sildenafil] lethality. Identical data to that with afatinib were obtained knocking down PI3K p110α/β or using buparlisib, copanlisib or the specific p110α inhibitor BYL719. Afatinib adapted NSCLC clones were resistant to buparlisib or copanlisib but were more sensitive than control clones to [sorafenib + sildenafil] or [pazopanib + sildenafil]. Lapatinib significantly enhanced the anti-tumor effect of [regorafenib + sildenafil] in vivo; afatinib and BYL719 enhanced the anti-tumor effects of [sorafenib + sildenafil] and [pazopanib] in vivo, respectively.

Deconvoluting the relationships between autophagy and metastasis for potential cancer therapy

Autophagy is a highly conserved lysosome-dependent degradation process that may digest some long-lived proteins and damaged organelles. As an essential homeostasis maintaining system in normal cells, autophagy plays a key role in several pathological settings, especially cancer. Metastasis, known as a crucial hallmark of cancer progression, is the primary cause of cancer lethality. The role of autophagy in metastasis is quite complex as supportive evidence has indicated both pro-metastatic and anti-metastatic functions of autophagy. Autophagy can inhibit metastasis by restricting necrosis and mediating autophagic cell death, whereas it may also promote metastasis by enhancing cancer cell fitness in response to stress. Moreover, the function of autophagy is context- and stage-dependent. Specifically, during the early steps of metastasis, autophagy mainly serves as a suppressor, while it plays a pro-metastatic role in the later steps. Here, we focus on highlighting the dual roles of autophagy in metastasis and address the molecular mechanisms involved in this process, which may provide a new insight into cancer biology. While, we also summarize several anti-metastatic agents manipulating autophagy, in the hope of shedding light on exploration of potential novel drugs for future cancer therapy.

Overexpression of ING5 inhibits HGF-induced proliferation, invasion and EMT in thyroid cancer cells via regulation of the c-Met/PI3K/Akt signaling pathway

The inhibitor of growth 5 (ING5), a novel member of the ING family, is involved in diverse biological processes such as cell growth, apoptosis and DNA repair. Recently, ING5 has been reported to be associated with cancer development. However, its specific role in thyroid cancer has yet to be elucidated. In this study, we found that the expression of ING5 was significantly down-regulated in human thyroid cancer tissues and cell lines. In addition, overexpression of ING5 markedly inhibited hepatocyte growth factor (HGF)-induced proliferation, invasion and epithelial-mesenchymal transition (EMT) of thyroid cancer cells as well as suppressed the tumor growth and metastasis in vivo. Furthermore, our data showed that the c-Met/PI3K/Akt signaling pathway was responsible for the inhibitory effect of ING5 on the thyroid cancer. Taken together, these findings provided an essential basis for the tumor-suppression role of ING5 in thyroid cancer.

The roles of ING5 expression in ovarian carcinogenesis and subsequent progression: a target of gene therapy

Here, we found that ING5 overexpression suppressed cell viability, glucose metabolism, migration, invasion and epithelial-mesenchymal transition, and induced cell arrest, apoptosis, senescence, autophagy and fat accumulation in ovarian cancer cells. ING5-mediated chemoresistance was positively linked to apoptotic resistance and chemoresistance-related gene expression. ING5 overexpression suppressed tumor growth of ovarian cancer by decreasing proliferation, and inducing apoptosis and autophagy. ING5 mRNA level was lower in ovarian cancer than normal ovary, and borderline than benign tumors (p < 0.05), and negatively correlated with vascular invasion, lymphatic invasion and FIGO staging of ovarian cancer (p < 0.05). ING5 protein was less expressed in primary cancer than normal ovary (p < 0.05). There was a negative correlation between ING5 mRNA expression and the overall or progression-free survival time of the cancer patients with Grade 2, Grade 3, and stage I cancer (p < 0.05). Immunohistochemically, ING5 was less expressed in serous and mucinous adenocarcinoma than miscellaneous subtypes, and positively correlated with dedifferentiation and ki-67 expression of ovarian cancer (p < 0.05). These data suggested that down-regulated ING5 expression might be involved in ovarian carcinogenesis possibly by suppressing aggressive phenotypes, including proliferation, tumor growth, migration, invasion, and anti-apoptosis.

ING5 activity in self-renewal of glioblastoma stem cells via calcium and follicle stimulating hormone pathways

Stem cell-like brain tumor initiating cells (BTICs) cause recurrence of glioblastomas, with BTIC 'stemness' affected by epigenetic mechanisms. The ING family of epigenetic regulators (ING1-5) function by targeting histone acetyltransferase (HAT) or histone deacetylase complexes to the H3K4me3 mark to alter histone acetylation and subsequently, gene expression. Here we find that ectopic expression of ING5, the targeting subunit of HBO1, MOZ and MORF HAT complexes increases expression of the Oct4, Olig2 and Nestin stem cell markers, promotes self-renewal, prevents lineage differentiation and increases stem cell pools in BTIC populations. This activity requires the plant homeodomain region of ING5 that interacts specifically with the H3K4me3 mark. ING5 also enhances PI3K/AKT and MEK/ERK activity to sustain self-renewal of BTICs over serial passage of stem cell-like spheres. ING5 exerts these effects by activating transcription of calcium channel and follicle stimulating hormone pathway genes. In silico analyses of The Cancer Genome Atlas data suggest that ING5 is a positive regulator of BTIC stemness, whose expression negatively correlates with patient prognosis, especially in the Proneural and Classical subtypes, and in tumors with low SOX2 expression. These data suggest that altering histone acetylation status and signaling pathways induced by ING5 may provide useful clinical strategies to target tumor resistance and recurrence in glioblastoma.

The nucleocytoplasmic translocation and up-regulation of ING5 protein in breast cancer: a potential target for gene therapy

Here, we found that ING5 overexpression resulted in a lower proliferation, reduced glucose metabolism, S arrest, decreased migration and invasion, apoptotic induction, fat accumulation, autophagy, senescence and mesenchymal-epithelial–transition of breast cancer cells. It also suppressed the tumor growth of breast cancer cells by inhibiting proliferation, inducing apoptosis and autophagy. ING5-mediated chemoresistance was positively linked to Akt and NF-κB activation, MRP1 and GST-π overexpression, and FBXW7 hypoexpression. ING5 expression was higher in breast cancer than normal tissue at both mRNA and protein levels. ING5 mRNA expression was positively correlated with relapse- and distant metastasis-free survival rates. Nuclear ING5 expression showed gradual decrease from breast normal tissue, fibroadenoma, adenomatosis, primary to metastatic cancers, while versa for cytoplasmic ING5. Nuclear ING5 expression was negatively correlated with distant metastasis and p53 hypoexpression, while cytoplasmic ING5 expression was positively correlated with tumor size and ER expression. These data suggested that up-regulated expression and nucleocytoplasmic translocation of ING5 protein were observed in breast cancer. The higher expression of nuclear ING5 was inversely linked to worse clinicopathological behaviors of breast cancer by in vivo and vitro reversing aggressive phenotypes. Therefore, it should be employed as a biomarker to indicate the tumorigenesis and aggressiveness of breast cancer, and as a potential target for gene therapy.

The roles of ING5 in gliomas: a good marker for tumorigenesis and a potential target for gene therapy

To elucidate the anti-tumor effects and molecular mechanisms of ING5 on glioma cells, we overexpressed it in U87 cells, and examined the phenotypes and their relevant molecules. It was found that ING5 overexpression suppressed proliferation, energy metabolism, migration, invasion, and induced G₂/M arrest, apoptosis, dedifferentiation, senescence, mesenchymal- epithelial transition and chemoresistance to cisplatin, MG132, paclitaxel and SAHA in U87 cells. There appeared a lower expression of N-cadherin, Twist, Slug, Zeb1, Zeb2, Snail, Ac-H3, Ac-H4, Cdc2, Cdk4 and XIAP, but a higher expression of Claudin 1, Histones 3 and 4, p21, p53, Bax, β-catenin, PI₃K, Akt, and p-Akt in ING5 transfectants. ING5 overexpression suppressed tumor growth of U87 cells in nude mice by inhibiting proliferation and inducing apoptosis. Down-regulated ING5 expression was closely linked to the tumorigenesis and histogenesis of glioma. These data indicated that ING5 expression might be considered as a good marker for the tumorigenesis and histogenesis of gliomas. It might be employed as a potential target for gene therapy of glioma. PI₃K/Akt or β-catenin/TCF-4 activation might be positively linked to chemotherapeutic resistance, mediated by ING5.

ING5 suppresses breast cancer progression and is regulated by miR-24

Background

The inhibitor of growth (ING) gene family of tumor suppressors is involved in multiple cellular functions such as cell cycle regulation, apoptosis, and chromatin remodeling. ING5 is a new member of the ING family whose function and regulation remain largely unknown.

Methods

Quantitative real-time PCR and western blot were used to examine the expression levels of ING5 in breast cancer tissues. The miRNAs that potentially targeted ING5 were determined by bioinformatics analysis and luciferase reporter assay. Cell viability assay, transwell invasion and apoptosis assay were used to characterize the changes induced by overexpressing or knocking down miR-24 or ING5. Hematoxylin and eosin (H&E) staining and immunohistochemical staining for ING5 and Ki-67 were used for xenograft assays in BALB/c nude mice.

Results

We showed that the ING5 protein rather than the mRNA, was significantly downregulated in breast cancer tissues. We also investigated the potential function of ING5 in breast tumorigenesis and found that ING5 suppressed the proliferation and invasion of breast cancer cells and promoted their apoptosis. Furthermore, we explored the molecular mechanisms accounting for the dysregulation of ING5 in breast cancer cells and identified an oncomiR, miR-24, as a direct upstream regulator of ING5. We revealed that miR-24 had the opposite effects to those of ING5 on breast cancer cells and could accelerate xenografted tumor growth in vivo.

Conclusion

Our findings uncover the tumor-suppressive role of ING5 and the regulatory pathway of ING5 in breast cancer and may provide insights into the molecular mechanisms of breast carcinogenesis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-017-0658-z) contains supplementary material, which is available to authorized users.

ING5 knockdown enhances migration and invasion of lung cancer cells by inducing EMT via EGFR/PI3K/Akt and IL-6/STAT3 signaling pathways

ING5 belongs to the Inhibitor of Growth (ING) candidate tumor suppressor family, whose functions have been involved in the regulation of chromatin remodeling, cell cycle progression, proliferation and apoptosis. Our previous study has shown that ING5 overexpression inhibits lung cancer aggressiveness via suppressing epithelial to mesenchymal transition (EMT). However, the mechanisms remain largely unknown. In the current study, by Phospho-Kinase array and western blot, we have defined significantly upregulated EGFR/PI3K/Akt and IL-6/STAT3 oncogenic signaling pathways in ING5 knockdown A549 cells, which could be downregulated by ING5 overexpression. PI3K inhibitor ZSTK474 or STAT3 inhibitor Niclosamide not only abolished ING5 knockdown-promoted proliferation, colony formation, migration and invasion of lung cancer A549 cells, but also impaired ING5 knockdown-stimulated metastasis of cancer cells in mouse xenograft models with tail vein injection of A549 cells. Furthermore, treatment with ZSTK474 or Niclosamide decreased protein level of EGFR, p-Akt, IL-6 and p-STAT3, and reversed ING5 knockdown-promoted EMT, as indicated by downregulated expression of EMT marker E-cadherin, an epithelial marker, increased expression of N-cadherin, a mesenchymal marker, and EMT-related transcription factors including Snail, Slug, Smad3 and Twist. Taken together, these results demonstrate that loss of ING5 enhances aggressiveness of lung cancer cells by promoting EMT via activation of EGFR/PI3K/Akt and IL-6/STAT3 signaling pathways.

Lysosomal acid phosphatase 2 is an unfavorable prognostic factor but is associated with better survival in stage II colorectal cancer patients receiving chemotherapy

Colorectal cancer (CRC) is one of the leading cancers worldwide. Surgery is the main therapeutic modality for stage II CRC. However, the implementation of adjuvant chemotherapy remains controversial and is not universally applied so far. In this study, we found that the protein expression of lysosomal acid phosphatase 2 (ACP2) was increased in CRC and that stage II CRC patients with high ACP2 expression showed a poorer outcome than those with low ACP2 expression (p = 0.004). To investigate this discrepancy, we analyzed the relation between ACP2 expression and several clinical cofactors.

Among patients who received chemotherapy, those with an high expression of ACP2 showed better survival in both stage II and III CRC than those with low ACP2 expression. In stage II CRC patients, univariate analysis showed ACP2 expression and T stage to be cofactors significantly associated with overall survival (ACP2: p = 0.006; T stage: p = 0.034). Multivariate Cox proportion hazard model analysis also revealed ACP2 to be an independent prognostic factor for overall survival (ACP2: p = 0.006; T stage: p = 0.041). Furthermore, ACP2-knockdown CRC cells showed an increase in chemoresistance to 5-FU treatment and increased proliferation marker in the ACP2 knockdown clone.

Taken together, our results suggested that ACP2 is an unfavorable prognostic factor for stage II CRC and may serve as a potential chemotherapy-sensitive marker to help identify a subset of stage II and III CRC patients for whom chemotherapy would improve survival.

MiR-1307 promotes ovarian cancer cell chemoresistance by targeting the ING5 expression

Background

We aimed to investigate the function of miR-1307 in chemoresistance and to explore its chemoresistance mechanism in ovarian cancer.

Methods

IC50 determination was used to test the chemoresistance profling in ovarian cancer cells. QRT-PCR or western blot was used to validate the expression level of miR-1307 and candidate gene or protein. Colony formation assay and FITC-labeled enhanced Annexin V immunofluorescence were used to compare cell proliferation and apoptosis ability, respectively. The potential target gene and its biological function of miRNA-1307 were also analyzed. Bioinformatics and Luciferase Reporter Gene Assay were conducted to validate the regulation of miRNA-1307 on the ING5 expression. Xenografts assay was used to demonstrate the inhibiting effect of miR-1307 ASO and Taxol therapy against ovarian cancer in vivo.

Results

MiR-1307 was over-expressed in chemoresistant ovarian cancer cell line A2780/Taxol, and over-expression or loss of miR-1307 promoted or inhabited chemoresistance. And we also found that the over-expression of miR-1307 promoted proliferation and inhibited apoptosis in ovarian cancer cells. Besides, we demonstrated that ING5 was a direct target of miR-1307 and miR-1307 down-regulated the ING5 expression in ovarian cancer cells. Additionally, we showed that ING5 inhibited cell proliferation, promoted cell apoptosis and inhabited chemoresistance reversely. Furthermore, the up-regulated ability of cell apoptosis and down-regulated ability of chemoresistance following the loss of miR-1307 was reversed by adding ING5 siRNA in vitro. Finally, we proved the inhibiting effect of miR-1307 ASO and Taxol therapy by increasing the ING5 expression against ovarian cancer through xenografts assay in vivo.

Conclusion

Our results suggested that miR-1307 could promote ovarian cancer chemoresistance by targeting the ING5 expression and miR-1307 might serve as a therapeutic target for ovarian cancer.

Parthenolide induces MITF-M downregulation and senescence in patient-derived MITF-M(high) melanoma cell populations

The activity of the M isoform of microphthalmia-associated transcription factor (MITF-M) has been attributed to regulation of differentiation, proliferation, survival and senescence of melanoma cells. MITF expression was shown to be antagonized by the activation of transcription factor NF-κB. Parthenolide, an inhibitor of NF-κB, has not been yet reported to affect MITF-M expression. Our results obtained in patient-derived melanoma cell populations indicate that parthenolide efficiently decreases the MITF-M level. This is neither dependent on p65/NF-κB signaling nor RAF/MEK/ERK pathway activity as inhibition of MEK by GSK1120212 (trametinib) and induction of ERK1/2 activity by parthenolide itself do not interfere with parthenolide-triggered depletion of MITF-M in both wild-type BRAF and BRAF^V600E melanoma populations. Parthenolide activity is not prevented by inhibitors of caspases, proteasomal and lysosomal pathways. As parthenolide reduces MITF-M transcript level and HDAC1 protein level, parthenolide-activated depletion of MITF-M protein may be considered as a result of transcriptional regulation, however, the influence of parthenolide on other elements of a dynamic control over MITF-M cannot be ruled out. Parthenolide induces diverse effects in melanoma cells, from death to senescence. The mode of the response to parthenolide is bound to the molecular characteristics of melanoma cells, particularly to the basal MITF-M expression level but other cell-autonomous differences such as NF-κB activity and MCL-1 level might also contribute. Our data suggest that parthenolide can be developed as a drug used in combination therapy against melanoma when simultaneous inhibition of MITF-M, NF-κB and HDAC1 is needed.

INGs are potential drug targets for cancer

PURPOSE

The inhibitor of growth (ING) family consists of ING1, ING2, ING3, ING4 and ING5, which function as the type II tumor suppressors. INGs regulate cell proliferation, senescence, apoptosis, differentiation, angiogenesis, DNA repair, metastasis, and invasion by multiple pathways. In addition, INGs increase cancer cell sensitivity for chemotherapy and radiotherapy, while clinical observations show that INGs are frequently lost in some types of cancers. The aim of the study was to summarize the recent progress regarding INGs regulating tumor progression.

METHODS

The literatures of INGs regulating tumor progression were searched and assayed.

RESULTS

The regulating signaling pathways of ING1, ING2, ING3 or ING4 on tumor progression were shown. The mechanisms of INGs on tumor suppression were also assayed.

CONCLUSIONS

This review better summarized the signaling mechanism of INGs on tumor suppression, which provides a candidate therapy strategy for cancers.

ING5 inhibits epithelial-mesenchymal transition in breast cancer by suppressing PI3K/Akt pathway

Epithelial-mesenchymal transition (EMT) is a crucial step in tumor progression and has an important role during cancer invasion and metastasis. The proteins of the inhibitor of growth (ING) candidate tumor suppressor family are involved in multiple cellular functions such as cell cycle regulation and apoptosis. ING5 is a member of the family. However, the role of ING5 in breast cancer is still unclear. Thus, the aim of this study is to explore the role of ING5 in breast cancer. In the present study, we showed that ING5 is involved in the pathogenesis of breast cancer. ING5 is down-regulated in breast cancer tissues and cell lines. Overexpression of ING5 significantly inhibited breast cancer cell migration, invasion, and EMT phenotype, moreover, overexpression of ING5 significantly the phosphorylation of PI3K and Aktin in breast cancer cells. In conclusion, our findings show that ING5 can efficiently inhibit the EMT progression in breast cancer cells by suppressing PI3K/Akt signaling pathway. Therefore, ING5 may be a good molecular target for the prevention and treatment of breast cancer.