ING1 Research Articles

Evaluation of a Synthetic PEI-based Polymeric Vector for ING4 Gene Delivery to MCF-7 Breast Cancer Cells

Evaluation of a Synthetic PEI-based Polymeric Vector for ING4 Gene Delivery to MCF-7 Breast Cancer Cells

DNA Profiling of ING1 Gene in Triple Negative Breast Cancer

DNA Profiling of ING1 Gene in Triple Negative Breast Cancer

MtING2 encodes an ING domain PHD finger protein which affects Medicago growth, flowering, global patterns of H3K4me3, and gene expression.

Flowering of the reference legume Medicago truncatula is promoted by winter cold (vernalization) followed by long-day photoperiods (VLD) similar to winter annual Arabidopsis. However, Medicago lacks FLC and CO, key regulators of Arabidopsis VLD flowering. Most plants have two INHIBITOR OF GROWTH (ING) genes (ING1 and ING2), encoding proteins with an ING domain with two anti-parallel alpha-helices and a plant homeodomain (PHD) finger, but their genetic role has not been previously described. In Medicago, Mting1 gene-edited mutants developed and flowered normally, but an Mting2-1 Tnt1 insertion mutant and gene-edited Mting2 mutants had developmental abnormalities including delayed flowering particularly in VLD, compact architecture, abnormal leaves with extra leaflets but no trichomes, and smaller seeds and barrels. Mting2 mutants had reduced expression of activators of flowering, including the FT-like gene MtFTa1, and increased expression of the candidate repressor MtTFL1c, consistent with the delayed flowering of the mutant. MtING2 overexpression complemented Mting2-1, but did not accelerate flowering in wild type. The MtING2 PHD finger bound H3K4me2/3 peptides weakly in vitro, but analysis of gene-edited mutants indicated that it was dispensable to MtING2 function in wild-type plants. RNA sequencing experiments indicated that >7000 genes are mis-expressed in the Mting2-1 mutant, consistent with its strong mutant phenotypes. Interestingly, ChIP-seq analysis identified >5000 novel H3K4me3 locations in the genome of Mting2-1 mutants compared to wild type R108. Overall, our mutant study has uncovered an important physiological role of a plant ING2 gene in development, flowering, and gene expression, which likely involves an epigenetic mechanism.

Abstract P5-09-04: Regulation of mTOR signaling pathway by ING4 in breast cancer: A new target in cancer therapy

Abstract Background: Breast cancer (BC) is one of the most diagnosed tumors in the United States. The mechanism of the disease development and progression is complex and still not fully understood. Dysregulation or change in the expression of transcription factors has been proposed as a possible cause of the disease severity and poor prognosis. The INhibitor of Growth family member 4 (ING4) is a tumor suppressor that has been connected to various cancer-related processes. Therefore, this study aims to assess the global gene regulation of BC cells by ING4 and identify the associated cellular processes and molecular pathways related to BC following ING4 loss. Methods: siRNA Knockdown and CRISPR Knockout technologies were used to deplete ING4 expression. Real-time PCR, RNA-Seq and Chip-Seq were used to identify gene expression alteration and ING4 enrichment on target promoters. Ingenuity Pathways Analysis (IPA®) was used to highlight candidates, networks and cellular processes. Results: Protein and RNA levels of ING4 were significantly reduced in MDA-231 knockdown and MCF7 knockout cells using siRNA and CRISPR technologies. RNA-Seq of BC cells revealed a large set of differentially expressed genes were regulated following ING4 loss. Key genes and biological networks related to cellular processes, including amino acid metabolism, cancer, cellular development, cellular growth and proliferation, were identified using IPA®. Chip-seq also revealed that ING4 was recruited to genes important in BC development and progression. Several genes were validated using the RT-qPCR method, and results were consistent with RNA-seq and Chip-seq data. Importantly, MDA-231 cells grown in stripped serum have shown an upregulation of the ribosomal protein S6 phosphorylation (PS6), an mTOR target protein, following ING4 knockdown. Treatment of MDA-231 cells with rapamycin blocked the phosphorylation of S6 induced by ING4 loss. An increase in S6 phosphorylation was also observed in MCF7 knockout cells grown either in regular or serum-free growth medium. The phosphorylation was reversed by amino acid transporter inhibitors JPH and BCH. Conclusion: The present study shows that ING4 regulates many genes involved in biological pathways and networks related to BC development and progression. Importantly, ING4 is a novel regulator of the mTOR pathway. Collectively, regulation of ING4 gene expression and its downstream molecules provides a novel approach in cancer treatment. Citation Format: Aymen Shatnawi, Travis Salisbury. Regulation of mTOR signaling pathway by ING4 in breast cancer: A new target in cancer therapy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-09-04.

ING4 Expression Landscape and Association With Clinicopathologic Characteristics in Breast Cancer

BackgroundBreast cancer (BC) development and progression is complex and still not fully understood. The expression or dysregulation of a variety of transcription factors has been suggested as contributing to disease severity and a poor prognosis. Therefore, the present study was designed to systematically outline ING4 expression and characteristics in clinical samples and cell lines of BC. Materials and MethodsA METABRIC (Molecular Taxonomy of Breast Cancer International Consortium) dataset was obtained from a cBioPortal public domain. ING4 gene expression, putative copy number alterations, and pertinent tumor information were retrieved. ING4 gene expression was identified for 1904 BC patients. ING4 mRNA expression data in BC cell lines were obtained from the Cancer Cell Line Encyclopedia. Analyses were conducted for associations between ING4 expression and age at diagnosis, tumor clinicopathologic characteristics, and molecular subtypes. The prognostic value of ING4 in BC patients was evaluated using Kaplan-Meier survival analysis. ResultsThe ING4 mRNA expression log intensity mean was 6.95, and 1005 (52.8%) of patients were determined to have high ING4 mRNA expression (mRNA log intensity > 6.95). Although ING4 gene expression correlated significantly and negatively with the Nottingham Prognostic Index and the number of positive lymph nodes (P < .05) and positively with overall survival time (P < .001). However, these correlations were weak in magnitude (r ∼ 0.1). The expression of ING4 was significantly associated with tumor grade, hormone receptor expression, human epidermal growth factor receptor 2, and molecular subtype. ING4 copy number alteration was also significantly associated with several clinicopathologic and prognostic factors. Kaplan-Meier survival analysis demonstrated greater overall survival for BC patients with high ING4 expression (P = .0046). Stratification of the data by menopausal status and tumor characteristics revealed a significant effect of ING4 expression on survival among premenopausal patients and women with a nonluminal subtype. Furthermore, the expression of ING4 in BC cell lines was significantly greater in luminal A and basal-like cells compared with human epidermal growth factor receptor 2-positive cells, which was also observed in the clinical samples. ConclusionsThe present study showed that ING4 gene expression is modulated in BC. High ING4 gene expression was associated with favorable prognostic parameters and positive clinical outcomes in our series of BC patients. ING4 could be used as a potential therapeutic target in BC-targeted therapy.

Preparation, characterization and evaluation of solid lipid nanoparticles and niosomes for ING4 gene delivery to MCF-7 cells

Preparation, characterization and evaluation of solid lipid nanoparticles and niosomes for ING4 gene delivery to MCF-7 cells

Abstract 5253: Regulation of estrogen related receptor α by ING4 and its potential role in breast cancer pathogenesis

Abstract Breast cancer is one of the most frequently diagnosed tumors in the United States that affects one in eight women during their lifetime. It is second only to lung cancer as cause of cancer death in women. The orphan members of the nuclear receptor superfamily, estrogen-related receptors ERRα and γ (ERRs) isoforms are considered the master regulators of energy metabolism and their transcriptional pathways are highly associated with the cancer phenotype. Realizing the important function of co-regulators on ERRs transcriptional activity and their impact on cancer development and progression, we have identified the tumor growth family member 4 (ING4), a protein that has been implicated in several solid tumors and physically interacts with ERRα in breast cancer cellular models and modulates its transcriptional activity. Examination of the Oncomine database revealed that both ING4 and ERRα gene expression were significantly higher in invasive ductal and lobular breast carcinomas compared to normal ones, and their increased expression is inversely correlated with the overall patient survival rate in The Cancer Genome Atlas (TCGA) database. Knocking down ING4 in a breast cancer cell line using siRNA technology significantly decreased the expression of ERRα, and overexpression of ING4 upregulates the endogenous expression of ERRα. Well-defined ERRα target genes were also regulated by ING4 in the same manner as ERRα. Also, depleting ING4 expression significantly increased breast cancer cell migration in in vitro scratch assays, while both ING4 and ERRα knockdown decreased breast cancer cell proliferation. Collectively, these findings provide evidence for positive regulation of ERRα by ING4. Understanding the mechanism by which ING4/ERRα interaction regulates cellular pathways in breast cancer, underscores the impact of such regulation on biological and pharmacological actions. Thus, they can be used for the development of improved novel pharmaceuticals that target ERRα/ING4 complex or its downstream pathways. Citation Format: Aymen A. Shatnawi, Vincent Giguere. Regulation of estrogen related receptor α by ING4 and its potential role in breast cancer pathogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5253.

Gene expression of ING4 gene in pancreatic cancers and splice forms of ING4 gene

Pancreatic cancer is characterized by rapid metastasis and resistant to medical treatments. As the other cancers, mutationsoftumor suppressor genes that involved in suppression of cell growth are observed in pancreatic cancers. ING4 protein is one of the proteins involved in the regulation of p53 tumor suppressor gene functions. ING4 involved in suppression of cell proliferation, chromosome rearrangement, cell migration, and angiogenesis. In this study, gene expressions and splicing variants of ING4 gene were investigated. Fresh tumor and normal specimens of the same pancreatic cancer patients were used. Gene expression study carried out by calculating the brightness of the bands on agarose gel and splicing variants were detected by direct sequencing. According to the results, three splice forms of ING4 and a decrease in gene expression of ING4 were determined. Splicing type of ING4 affects the translocation of ING4 proteins into the nucleus. To determine the gene expression of each splicing variant, will further clarify the role of ING4 in pancreatic cancers.

Synergistic suppression effect on tumor growth of acute myeloid leukemia by combining cytarabine with an engineered oncolytic vaccinia virus.

BackgroundIn consideration of the drug resistance and side effects associated with cytarabine, one of the most effective drugs for the treatment of acute myeloid leukemia (AML), there is a need for safer and effective strategies.MethodsIn the present investigation, we fabricated a new oncolytic vaccinia virus (oVV-ING4), which expresses the inhibitor of growth family member 4 (ING4) and explored its antitumor activity individually and in combination with cytarabine in AML cells.ResultsThe experiments confirmed that oVV can efficiently and specifically infect leukemia cells, and augment the ING4 gene expression. Flow cytometry and western blot demonstrated that oVV-ING4 enhances apoptosis and G2/M phase arrest in AML cells, and causes remarkable cancer cell death. In addition, the synergistic efficiency of oVV-ING4 and cytarabine was investigated in vitro and in vivo; the combination significantly inhibited the survival of leukemia cells in vitro and xenografted KG-1 AML tumor growth in vivo.ConclusionIn brief, oVV-ING4 can increase the sensitivity of leukemia cells to cytarabine and induce cell apoptosis in vitro and in vivo. Thus, oVV-ING4 may be a promising therapeutic candidate for leukemia and in combination with cytarabine represents a potential antitumor therapy.

Expression of growth inhibitory factor 2 in human esophageal squamous cell carcinoma and clinical significance

Objective To investigate the expression of growth inhibitory factor 2 (ING2) in esophageal squamous cell carcinoma (ESCC), and explore its correlation with lymphatic metastasis and prognosis. Methods The expression of ING2 in 63 cases of ESCC tissues and 63 cases of normal tissues was detected by immunohistochemistry. Real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) was used to examine the expression of ING2 mRNA in fresh tumoral and normal tissues. Results The ING2 positive staining was predominantly localized in both nucleus and cytoplasm of cancer cells, but weakly in nucleus of normal epithelial cells only. The expression of ING2 protein and mRNA was significantly higher in ESCC tissues than in normal tissues (P=0.001). Moreover, the expression level of ING2 protein in ESCC tissues was significantly correlated with grade (P=0.010) and lymph node metastasis (P=0.001). Cox regression analysis revealed that ING2 expression level (P=0.042) and lymph node metastasis (P=0.000) were independent prognostic factors of ESCC. Conclusion ING2 is overexpressed in ESCC tissues. High expression of ING2 correlates with pathological grades, lymphatic metastasis and unfavorable survival in ESCC. Key words: Esophageal neoplasms; Squamous cell; Growth inhibitory factor 2; Metastasis; Prognosis

Abstract 3326: Identification of a novel androgen receptor co-regulator in prostate cancer

Abstract Prostate cancer (PC) is one of the most frequently diagnosed tumors in the United States, affecting one in six men during their lifetime and second only to lung cancer as a cause of cancer death in men. One of the major drivers of prostate cancer is the androgen receptor (AR). It has been shown that deregulation of AR co-regulators play a crucial role in PC through modulating the transcriptional activity of the receptor. While the importance of the AR complex is well established, there is still an incomplete understanding of what all the associated co-regulators are and how they modulate AR signaling. Here, we have identified that the inhibitor of growth family member 4 (ING4), a protein that has been implicated in the pathogenesis of several solid tumors such as gastric and breast cancer, is a novel AR co-regulator. Overexpression of ING4 increased AR activity in an androgen-dependent manner as assessed using luciferase reporter gene assays. Supporting a role as a potential AR co-activator, RNA Next-Generation Sequencing of prostate cancer cells with ING4 knocked down revealed a repression of endogenous AR/R1881-activated genes and expression of AR/R1881 suppressed genes. Further, mining of existing clinical datasets revealed that the ING4 gene expression is de-regulated in PCs compared relative to normal tissue and tracks with poor patient prognosis. Collectively, the current findings strongly support the involvement of ING4 in AR signaling and PC progression and development. Citation Format: Aymen A. Shatnawi, Sridhar Acharya Malkaram, Efrosini Tsouko, Daniel E. Frigo. Identification of a novel androgen receptor co-regulator in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3326. doi:10.1158/1538-7445.AM2017-3326

Hypoxic regulation of the expression of cell proliferation related genes in U87 glioma cells upon inhibition of IRE1 signaling enzyme

We have studied the effect of inhibition of IRE1 (inositol requiring enzyme 1), which is a central mediator of endoplasmic reticulum stress and a controller of cell proliferation and tumor growth, on hypoxic regulation of the expression of different proliferation related genes in U87 glioma cells. It was shown that hypoxia leads to up-regulation of the expression of IL13RA2, CD24, ING1, ING2, ENDOG, and POLG genes and to down-regulation – of KRT18, TRAPPC3, TSFM, and MTIF2 genes at the mRNA level in control glioma cells. Changes for ING1 and CD24 genes were more significant. At the same time, inhibition of IRE1 modifies the effect of hypoxia on the expression of all studied genes. In particular, it increases sensitivity to hypoxia of the expression of IL13RA2, TRAPPC3, ENDOG, and PLOG genes and suppresses the effect of hypoxia on the expression of ING1 gene. Additionally, it eliminates hypoxic regulation of KRT18, CD24, ING2, TSFM, and MTIF2 genes expressions and introduces sensitivity to hypoxia of the expression of BET1 gene in glioma cells. The present study demonstrates that hypoxia, which often contributes to tumor growth, affects the expression of almost all studied genes. Additionally, inhibition of IRE1 can both enhance and suppress the hypoxic regulation of these gene expressions in a gene specific manner and thus possibly contributes to slower glioma growth, but several aspects of this regulation must be further clarified.

Expression and clinical significance of ING4 and HIF-1 alpha in brain astrocytoma

To study the mRNA expression level of growth inhibition factor 4 (ING4) and hypoxia inducing factor 1 alpha (HIF-1 alpha), and their relationship with tumor malignant degree or the pathology classification in human brain astrocytoma. The mRNA expression levels of ING4 and HIF-1 alpha were detected by RT-PCR method in 45 cases of grade I-IV human brain astrocytoma and 11 cases of control brain tissues from January 2009 to June 2010 in the Second Affiliated Hospital of Zhengzhou University, and their correlation was also analyzed. In the non-tumor brain tissue, the expression level of ING4 mRNA was 1.19 ± 0.22, while they were 0.91 ± 0.19, 0.74 ± 0.28, 0.54 ± 0.33 and 0.22 ± 0.19 in I-IV grade astrocytoma, respectively. Compared with the non-tumor control, the mRNA expression level of ING4 gene decreased significantly in the astrocytoma (P<0.05). And the expression of ING4 gradually reduced with the increase of the pathological classification of the astrocytoma.In the non-tumor brain tissue, the expression level of HIF-1 alpha mRNA was 0.26 ± 0.16, and they were 0.34 ± 0.19, 0.50 ± 0.23, 0.96 ± 0.15 and 1.04 ± 0.15 in I-IV grade astrocytoma, respectively.For HIF-1 alpha gene, the mRNA expression level increased significantly in the astrocytoma. Meanwhile, the expression gradually increased with the increase of the pathological classification of the astrocytoma (P<0.05). The mRNA expression showed a negative correlation between ING4 and HIF-1 alpha with the increase of the tumor malignant degree. The ING4 and HIF-1 alpha genes play a role in the tumorigenesis and development of human brain astrocytoma, and closely associate with the malignant degree of astrocytoma.

Adenovirus-mediated ING4 Gene Transfer in Osteosarcoma Suppresses Tumor Growth via Induction of Apoptosis and Inhibition of Tumor Angiogenesis.

The inhibitor of growth (ING) family proteins have been defined as candidate tumor suppressors. ING4 as a novel member of ING family has potential tumor-suppressive effects via multiple pathways. However, the therapeutic effect of adenovirus-mediated ING4 (Ad-ING4) gene transfer in human osteosarcoma is still unknown. In this study, we explored the in vitro and in vivo antitumor activity of Ad-ING4 in human osteosarcoma and its potential mechanism using a MG-63 human osteosarcoma cell line. We demonstrated that Ad-ING4 induced significant growth inhibition and apoptosis, upregulated the expression of P21, P27 and Bax, downregulated the Bcl-2 expression and activated Caspase-3 in MG-63 human osteosarcoma cells. Moreover, intratumoral injections of Ad-ING4 in athymic nude mice bearing MG-63 human osteosarcoma tumors significantly suppressed osteosarcoma xenografted tumor growth, increased the expression of P21, P27 and Bax, reduced the Bcl-2 and CD34 expression and microvessel density (MVD) in tumors. This retarded MG-63 osteosarcoma growth in vitro and in vivo in an athymic nude mouse model elicited by Ad-ING4 was closely associated with the increase in the expression of cell cycle-related molecules P21 and P27, decrease in the ratio of anti- to pro-apoptotic molecules Bcl-2/Bax followed by the activation of Caspase-3 leading to apoptosis via intrinsic apoptotic pathways, and the inhibition of tumor angiogenesis. Thus, our results indicate that Ad-ING4 is a potential candidate for human osteosarcoma gene therapy.

Analysis of loss of heterozygosity on chromosome 4q in hepatocellular carcinoma using high-throughput SNP array.

To identify tumour suppressor genes (TSGs) associated with hepatocellular carcinoma (HCC) on chromosome 4q using a high-throughput single nucleotide polymorphism (SNP) array, we first scanned for loss of heterozygosity (LOH) of 40 SNPs on chromosome 4q and discovered 2 hot regions: 4q24-26 and 4q34.3-35. We then further scanned for LOH of 338 SNPs in genes around 4q34.3-35 and discovered 3 genes with the most frequent LOH: nei endonuclease VIII-like 3 (NEIL3), interferon regulatory factor 2 (IRF2) and inhibitor of growth family member 2 (ING2). A review of the literature indicates only ING2 might be a TSG associated with HCC.

A novel tumor suppressor gene in basal cell carcinoma: inhibition of growth factor-2.

In loss of heterozygosity (LOH) studies at the chromosome 4q22-35 region, it was shown that the amount of deletion was high in basal cell carcinoma (BCC). It has been proposed that genes located in this chromosomal region could be tumor suppressor genes in BCC. It has been thought that deletions in the ING2 gene located in the same region can play a role in the pathophysiology of BCC and that deletions occurring in this region may influence the level of ING2 expression in BCC. Tumoral and non-tumoral tissues from 75 patients with BCC (45 men and 30 women) were included to the study. Lesions were excised by a surgical margin of 0.5 cm. After excision, RNA was isolated from tumoral and non-tumoral tissue samples. ING2 messenger RNA (mRNA) expression level was determined in tumoral and non-tumoral tissues by the real-time polymerase chain reaction (RT-PCR). It was detected that ING2 mRNA expression level decreased in tumoral tissues when compared to non-tumoral tissues from BCC patients (p = 0.0001). It was found that expression levels of this gene were comparable among patients with primary, recurrent, or multiple BCC. It is thought that ING2 gene expression level could contribute to the development of BCC but not be associated with the stage and the prognosis of the tumor.

Tumor cell apoptosis mediated by cytoplasmic ING1 is associated with improved survival in oral squamous cell carcinoma patients.

The ING1 epigenetic regulator and tumor suppressor plays a central role in apoptosis. The Ing1 gene is functionally inactivated in many cancer types but is rarely mutated. Although most studies have implicated the major ING1 isoform, p33ING1b, in nuclear apoptotic signalling, we recently discovered a novel and potent apoptosis-inducing effect of p33ING1b translocation to the mitochondria in response to DNA damage. In the present study, we examined the impact of cytoplasmic/mitochondrial localization of p33ING1b in oral squamous cell carcinoma (OSCC) patient samples and explored the therapeutic potential of adenovirally-overexpressed p33ING1b in OSCC cell lines in combination with ionizing radiation (IR) treatment. In contrast with previous reports, we found that p33ING1b protein and mRNA levels are higher in OSCC compared to normal epithelial cells. In OSCC patient samples, higher levels of intra-tumoral cytoplasmic p33ING1b correlated with increased apoptotic markers and significantly better patient survival. This association was strongest in patients who received post-operative radiotherapy. IR treatment induced p33ING1b translocation to the mitochondria and adenoviral-p33ING1b synergized with IR to kill OSCC cells. Our results identify a novel functional relationship between cytoplasmic p33ING1b and patient survival and highlight the potential for the use of p33ING1b as a therapeutic agent in combination with adjuvant radiotherapy in OSCC.

Adenovirus-mediated ING4 Gene Transfer in Osteosarcoma Suppresses Tumor Growth via Induction of Apoptosis and Inhibition of Tumor Angiogenesis.

The inhibitor of growth (ING) family proteins have been defined as candidate tumor suppressors. ING4 as a novel member of ING family has potential tumor-suppressive effects via multiple pathways. However, the therapeutic effect of adenovirus-mediated ING4 (Ad-ING4) gene transfer in human osteosarcoma is still unknown. In this study, we explored the in vitro and in vivo antitumor activity of Ad-ING4 in human osteosarcoma and its potential mechanism using a MG-63 human osteosarcoma cell line. We demonstrated that Ad-ING4 induced significant growth inhibition and apoptosis, upregulated the expression of P21, P27 and Bax, downregulated the Bcl-2 expression and activated Caspase-3 in MG-63 human osteosarcoma cells. Moreover, intratumoral injections of Ad-ING4 in athymic nude mice bearing MG-63 human osteosarcoma tumors significantly suppressed osteosarcoma xenografted tumor growth, increased the expression of P21, P27 and Bax, reduced the Bcl-2 and CD34 expression and microvessel density (MVD) in tumors. This retarded MG-63 osteosarcoma growth in vitro and in vivo in an athymic nude mouse model elicited by Ad-ING4 was closely associated with the increase in the expression of cell cycle-related molecules P21 and P27, decrease in the ratio of anti- to pro-apoptotic molecules Bcl-2/Bax followed by the activation of Caspase-3 leading to apoptosis via intrinsic apoptotic pathways, and the inhibition of tumor angiogenesis. Thus, our results indicate that Ad-ING4 is a potential candidate for human osteosarcoma gene therapy.

Knockdown of Inhibitor of Growth Protein 2 Inhibits Cell Invasion and Enhances Chemosensitivity to 5-FU in Human Gastric Cancer Cells

The inhibitor of growth (ING) family is involved in multiple cellular functions, but the role of ING2 in gastric cancer progression is unclear. To investigate the effects of ING2 gene knockdown on chemosensitivity to 5-fluorouracil (5-FU) in human gastric cancer cells and its possible mechanisms. Short hairpin RNA (shRNA) targeting ING2 (shING2) was transfected into MGC-803 cells using Lipofectamine 2000, and stable transfection cell lines were established using G418. Cell viability, cell cycle distribution, cell apoptosis, and invasive ability were measured to determine the influence of ING2 knockdown on cell biologic characteristics. Messenger RNA (mRNA) and protein levels of ING2, cyclin D1, NF-kappaB/p65, and several matrix metalloproteinases (MMPs) were determined by use of real-time polymerase chain reaction (PCR) or Western blotting, respectively. Our results showed that ING2 knockdown induced cell apoptosis and inhibited cell viability significantly (P < 0.05). Additionally, ING2 knockdown induced a specific G0/G1 arrest. Furthermore, the suppression of ING2 could enhance the chemosensitivity of gastric cancer cells to 5-FU significantly. Moreover, knockdown of ING2 expression significantly reduced cellular metastatic ability and expression of MMPs in MGC-803 cells. The expression of cyclin D1 and NF-kappaB/p65 was also markedly inhibited in MGC-803/shING2 cells compared with control cells. ING2 not only plays an essential role in the growth and invasion of MGC-803 cells but also represents a potential approach to chemosensitization therapy in human gastric cancer.

Expression and Analysis of P33/ING1 and HIF-1α in Invasive Ductal Carcinoma of Breast

Objective To study the expression and significance of P33/ING1 and HIF-1α in invasive ductal carcinoma of breast(IDC).Methods Immunohistochemical SP method was performed to detect the expression of P33/ING1 and HIF-1α in 68 cases of IDC and 20 cases of breast fibroadenoma and the relationship between the expression and clinical-pathological characteristics was analyzed.Results The positive expression rates of P33/ING1 protein in IDC was significant lower than that in breast fibroadenoma(60.29% vs.95%;P0.01);and negatively correlated with tumor size,axillary lymph node metastasis and histologic grade(P0.05).The positive expression rates of HIF-1α protein in IDC was significant higher than that in breast fibroadenoma(52.94% vs.10%;P0.01) and positively correlated with axillary lymph node metastasis and histologic grade(P0.05).There was a negatively correlation between P33/ING1 and HIF-1α in IDC(r=-0.283;P0.05).Conclusion There were low-expression of P33/ING1 and over-expression of HIF-1α in IDC.P33/ING1 and HIF-1α proteins were significantly correlated with the clinicopathological characteristics in IDC.Combined detection of P33/ING1 and HIF-1α might calculate the biological behaviors of IDC.