The role of PinX1 in growth control of breast cancer cells and its potential molecular mechanism by mRNA and lncRNA expression profiles screening

LncRNA GAS5 inhibits Invasion and Migration of Lung Cancer through influencing EMT process

Background: Lung cancer is a malignant tumor in mammary gland epithelium with high morbidity and mortality among women worldwide. Long noncoding RNA GAS5 (GAS5) has been proved to be closely related with tumor progression. However, the influence of GAS5 on lung cancer and the specific mechanism remain unclear.

Methods: Cell invasion, cell migration, cell apoptosis and cell cycle were investigated after transfection with pcDNA-GAS5 and sh-GAS5. Sizes of tumors were measured by establishing transplanted tumor model in vivo. E-cadherin and N-cadherin expressions were investigated.

Results: Cell invasion and migration were inhibited markedly in GAS5 overexpressed cell line. Cell cycle results indicated that the percentage of S-phase cells was increased, and G2-phase was reduced in the GAS5 overexpression cell line. Tumor size was suppressed obviously after GAS5 overexpression treatment. GAS5 markedly inhibited the expression of E-cadherin and induced the expression of N-cadherin. GAS5 overexpression significantly inhibited lung cancer cell proliferation by increasing the E-cadherin and decreasing N-cadherin.

Conclusions: These findings provide novel evidence that GAS5 can be viewed as an anti-lung cancer agent through affecting EMT pathway.

Effects of LncRNA Lnc-LIF-AS on cell proliferation, migration and invasion in a human cervical cancer cell line

This study explored the effect of LncRNA Lnc-LIF-AS on cell proliferation, migration and invasion in the human cervical cancer (HCC) cell line SiHa. SiHa cells had the lowest expression of Lnc-LIF-AS in the 4 human cervical cancer cell lines (SiHa, ME-180, C-33A and HeLa) and were transfected and divided into the SiHa/con (transfected with pMIGRI) cell group, SiHa/Lnc-LIF-AS (transfected with pMIGRI-Lnc-LIF-AS) cell group, and SiHa/Lnc-LIF-AS-DN (transfected with pMIGRI-Lnc-LIF-AS-DN, in which the sequences overlapping with LIF mRNA was deleted) cell group. Overexpression of Lnc-LIF-AS could promote the proliferation, colony formation, invasion and migration in SiHa and ME-180 cells. And the low expression of Lnc-LIF-AS suppress the proliferation, colony formation invasion and migration in HeLa cells when the Lnc-LIF-AS expression has been suppressed. In the SiHa/Lnc-LIF-AS cells group, the cell cycle was mainly halted in the S phase and overexpression of Lnc-LIF-AS had no effect on the apoptosis of SiHa cells. Overexpression of Lnc-LIF-AS could promote the secretion of LIF in SiHa cells, and the supernatant from SiHa/Lnc-LIF-AS cells could promote cell proliferation in the SiHa/con cells. The STAT3 inhibitor could inhibit cell proliferation in the SiHa/Lnc-LIF-AS cells. The expression level of Lnc-LIF-AS in cervical cancer tissues was higher than that in normal tissues and the expression level of Lnc-LIF-AS was positively correlated with the level of LIF. In the SiHa/con and SiHa/Lnc-LIF-AS-DN cell groups, there were no significant differences in cell proliferation, cell migration and cell invasion. The overexpression of Lnc-LIF-AS can promote cell proliferation, migration and invasion in cervical cancer cells, and the core function domain of this lncRNA was located in the overlapping a 3'-UTR base sequence of LIF mRNA.

Naphthalene diimide-derivatives G-quadruplex ligands induce cell proliferation inhibition, mild telomeric dysfunction and cell cycle perturbation in U251MG glioma cells

In the present paper, the biological effects of three different naphthalene diimides (NDIs) G-quadruplex (G4) ligands (H-NDI-Tyr, H-NDI-NMe2, and tetra-NDI-NMe2) were comparatively evaluated to those exerted by RHPS4, a well-characterized telomeric G4-ligand, in an in vitro model of glioblastoma. Data indicated that NDIs were very effective in blocking cell proliferation at nanomolar concentrations, although displaying a lower specificity for telomere targeting compared to RHPS4. In addition, differently from RHPS4, NDIs failed to enhance the effect of ionizing radiation, thus suggesting that additional targets other than telomeres could be involved in the strong NDI-mediated anti-proliferative effects. In order to test telomeric off-target action of NDIs, a panel of genes involved in tumor progression, DNA repair, telomere maintenance, and cell-cycle regulation were evaluated at transcriptional and translational level. Specifically, the compounds were able to cause a marked reduction of TERT and BCL2 amounts as well as to favor the accumulation of proteins involved in cell cycle control. A detailed cytofluorimetric analysis of cell cycle progression by means of bromodeoxyuridine (BrdU) incorporation and staining of phospho-histone H3 indicated that NDIs greatly reduce the progression through S-phase and lead to G1 accumulation of BrdU-positive cells. Taken together, these data indicated that, besides effects on telomeres and oncogenes such as Tert and Bcl2, nanomolar concentrations of NDIs determined a sustained block of cell proliferation by slowing down cell cycle progression during S-phase. In conclusion, our data indicate that NDIs G4-ligands are powerful antiproliferative agents, which act through mechanisms that ultimately lead to altered cell-cycle control.

Mechanisms underlying the antiproliferative effects of a series of quinoxaline-derived chalcones

The present study aimed to characterize the effects of quinoxaline-derived chalcones, designed on the basis of the selective PI3Kγ inhibitor AS605240, in oral cancer cells. Three lead compounds, namely N9, N17 and N23, were selected from a series of 20 quinoxaline-derived chalcones, based on an initial screening using human and rat squamous cell carcinoma lineages, representing compounds with at least one methoxy radical at the A-ring. The selected chalcones, mainly N9 and N17, displayed marked antiproliferative effects, via apoptosis and autophagy induction, with an increase of sub-G1 population and Akt inhibition. The three chalcones displayed marked in vitro antitumor effects in different protocols with standard chemotherapy drugs, with acceptable toxicity on normal cells. There was no growth retrieval, after exposure to chalcone N9 alone, in a long-term assay to determine the cumulative population doubling (CPD) of human oral cancer cells. A PCR array evaluating 168 genes related to cancer and inflammation, demonstrated striking actions for N9, which altered the expression of 74 genes. Altogether, our results point out quinoxalinic chalcones, mainly N9, as potential strategies for oral cancer treatment.

Effects of LncRNA-HOST2 on cell proliferation, migration, invasion and apoptosis of human hepatocellular carcinoma cell line SMMC-7721

The present study explored the effect of long non-coding RNA-human ovarian cancer-specific transcript 2 (LncRNA-HOST2) on cell proliferation, migration, invasion and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721. HCC tissues and adjacent normal tissues from 162 HCC patients were collected. The HCC cell lines were assigned into the control group (regular culture), negative control (NC) group (transfected with siRNA) and experimental group (transfected with Lnc-HOST2 siRNA). Quantitative real-time PCR (qRT-PCR) was used to detect the expression of LncRNA-HOST2. Cell proliferation was detected by CCK-8 and colony-forming assays, cell apoptosis by flow cytometry and cell migration by Scratch test. Transwell assay was used to evaluate cell migration and invasion abilities. LncRNA-HOST2 expression in the HCC tissues increased 2-10 times than that in the adjacent normal tissues. Compared with the HL-7702 cell line, LncRNA-HOST2 expression in HepG2, SMMC-7721 and Huh7 cell lines was all up-regulated, but the SMMC-7721 cell had the highest Lnc-HOST2 expression. The LncRNA-HOST2 expression in the experimental group was down-regulated as compared with the control and NC groups. In comparison with the control and NC groups, cloned cells reduced, cell apoptosis increased, clone-forming ability weakened and inhibitory rate of colony formation increased in the experimental group. The cells migrating and penetrating into the transwell chamber were fewer in the experimental group than those in the control and NC groups. The experimental group exhibited slow wound healing and decreased cell migration area after 48 h. These findings indicate that LncRNA-HOST2 can promote cell proliferation, migration and invasion and inhibit cell apoptosis in human HCC cell line SMMC-7721.

The depletion of PinX1 involved in the tumorigenesis of non-small cell lung cancer promotes cell proliferation via p15/cyclin D1 pathway

Background

The telomerase/telomere interacting protein PinX1 has been suggested as a tumor suppressor. However, the clinical and biological significance of PinX1 in human non-small cell lung cancer (NSCLC) is unclear.

Methods

PinX1 gene/expression pattern and its association with NSCLC patient survival were analyzed in cBioportal Web resource and two cohorts of NSCLC samples. A series of in vivo and in vitro assays were performed to elucidate the function of PinX1 on NSCLC cells proliferation and underlying mechanisms.

Results

More frequency of gene PinX1 homozygous deletion and heterozygote deficiency was first retrieved from cBioportal Web resource. Low expression of PinX1 correlated with smoking condition, histological type, T stage, N stage, M stage and TNM stage, and was an independent predictor for overall survival in a learning cohort (n = 93) and a validation cohort (n = 51) of NSCLC patients. Furthermore, knockdown of PinX1 dramatically accelerated NSCLC cell proliferation and G1/S transition, whereas ectopic overexpression of PinX1 substantially inhibited cell viability and cell cycle transition in vitro and in vivo. p15/cyclin D1 pathway and BMP5 might contribute to PinX1-associated cell proliferation and cell cycle transition.

Conclusion

The cost-effective expression of PinX1 could constitute a novel molecular predictor/marker for NSCLC management.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-017-0637-4) contains supplementary material, which is available to authorized users.

Novel role for PINX1 as a coregulator of nuclear hormone receptors

Estrogen receptor alpha (ERα) has an established role in breast cancer biology. Transcriptional activation by ERα is a multistep process influenced by coactivator and corepressor proteins. This work shows that Pin2 interacting protein 1 (PINX1) interacts with the N-terminal domain of ERα and functions as a corepressor of ERα. Furthermore, it represses both AF-1 and AF-2 transcriptional activities. Chromatin immunoprecipitation assays verified that the interaction between ERα and PINX1 occurs on E2 regulated promoters and enhanced expression of PINX1 deregulates the expression of a number of genes that have a role in cell growth and proliferation in breast cancer. PINX1 overexpression decreases estrogen mediated proliferation of breast cancer cell lines, while its depletion shows the opposite effect. Taken together, these data show a novel molecular mechanism for PINX1 as an attenuator of estrogen receptor activity in breast cancer cell lines, furthering its role as a tumor suppressor gene in breast cancer.

8p deletion is strongly linked to poor prognosis in breast cancer

Deletions of chromosome 8p occur frequently in breast cancers, but analyses of its clinical relevance have been limited to small patient cohorts and provided controversial results. A tissue microarray with 2,197 breast cancers was thus analyzed by fluorescence in-situ hybridization using an 8p21 probe in combination with a centromere 8 reference probe. 8p deletions were found in 50% of carcinomas with no special type, 67% of papillary, 28% of tubular, 37% of lobular cancers and 56% of cancers with medullary features. Deletions were always heterozygous. 8p deletion was significantly linked to advanced tumor stage (P < 0.0001), high-grade (P < 0.0001), high tumor cell proliferation (Ki67 Labeling Index; P < 0.0001), and shortened overall survival (P < 0.0001). For example, 8p deletion was seen in 32% of 290 grade 1, 43% of 438 grade 2, and 65% of 427 grade 3 cancers. In addition, 8p deletions were strongly linked to amplification of MYC (P < 0.0001), HER2 (P < 0.0001), and CCND1 (p = 0.001), but inversely associated with ER receptor expression (p = 0.0001). Remarkably, 46.5% of 8p-deleted cancers harbored amplification of at least one of the analyzed genes as compared to 27.5% amplifications in 8p-non-deleted cancers (P < 0.0001). In conclusion, 8p deletion characterizes a subset of particularly aggressive breast cancers. As 8p deletions are easy to analyze, this feature appears to be highly suited for future DNA based prognostic breast cancer panels. The strong link of 8p deletion with various gene amplifications raises the possibility of a role for regulating genomic stability.

Long noncoding RNA aberrant expression profiles after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy of AGC ascertained by microarray analysis

Long noncoding RNAs (lncRNAs) have been shown to be involved in the development and progression of advanced gastric cancer (AGC). However, the roles of lncRNAs in advanced gastric cancer during the process of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are not well understood. A high-throughput microarray analysis was performed to compare the expression profiles of lncRNAs and messenger RNAs (mRNAs) in AGC serum samples during the process of CRS + HIPEC. Several potentially AGC-associated lncRNAs were verified by real-time quantitative reverse transcription polymerase chain reaction (PCR) analysis. Using abundant and varied probes, we were able to assess 33,045 lncRNAs and 30,215 mRNAs in our microarray. We found that 566 lncRNAs were differentially expressed (2-fold change) in AGC serum samples, indicating the significantly up- or downregulated lncRNAs play important roles in AGC during the process of CRS + HIPEC. Quantitative PCR results further verified that eight lncRNAs were aberrantly expressed in AGC serum samples after CRS + HIEC compared with matched serum sample before CRS + HIPEC. Among them, BC031243 and RP11-356I2.2 were the most aberrantly expressed lncRNAs, as estimated by quantitative PCR in six pairs of AGC serum samples. Our study demonstrated the expression patterns of lncRNAs in AGC serums before and after CRS + HIPEC by microarray. These results revealed that lncRNAs were differentially expressed during the process of CRS + HIPEC, suggesting that they might play key roles in tumor development.