scholarly journals Silencing SHMT2 inhibits the progression of tongue squamous cell carcinoma through cell cycle regulation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yan Liao ◽  
Fang Wang ◽  
Yadong Zhang ◽  
Hongshi Cai ◽  
Fan Song ◽  
...  

Abstract Background Serine hydroxymethyltransferase 2 (SHMT2) is a vital metabolic enzyme in one carbon metabolism catalyzing the conversion of serine to glycine, which has been reported to play a crucial role in the progression of tumors. However, its function in tongue squamous cell carcinoma (TSCC) remains unclear. Methods SHMT2 expression was analyzed using samples in online databases, and was assessed through immunohistochemistry staining of collected clinical specimens. The correlation between SHMT2 expression and the cell cycle was predicted through bioinformatic analysis, including weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA). After transfection with siRNA, CCK8 assay, Edu staining, flow cytometry, trans-well assay, and wound healing experiments were performed to verify the functional role of SHMT2 in vitro. A stable cell line with SHMT2 silencing was established to detect the oncogenic function of SHMT2 in vivo. Results The expression of SHMT2 was up-regulated in TSCC tissues and cell lines compared with normal groups, and highly expressed SHMT2 significantly indicated a poorer clinical outcome for TSCC patients. Bioinformatic analysis found that high expression of SHMT2 was closely related with biologic process including cell cycle and cell cycle G1/S transition. Down regulating of SHMT2 significantly suppressed the proliferation, invasive and migrative ability of TSCC cells, and induced the prolongation of the G1 phase of the cell cycle in vitro. Furthermore, western blot showed that cell cycle-related regulators such as cyclin-dependent kinase 4 (CDK4) and cyclinD1 expression levels were decreased, while the expression levels of the cyclin-dependent kinase inhibitors p21Cip1 and p27Kip1 were increased after SHMT2 knockdown. Silencing SHMT2 in the HN6 cell line using short hairpin RNA also impeded tumor growth in vivo. Conclusions Overexpression of SHMT2 in TSCC indicated low survival rates, and was associated with aggressive behaviors of TSCC. It was also found to be involved in cell cycle regulation of TSCC cells. SHMT2 may serve as a novel prognostic indicator of TSCC.

2020 ◽  
Author(s):  
Yan Liao ◽  
Fang Wang ◽  
Yadong Zhang ◽  
Hongshi Cai ◽  
Fan Song ◽  
...  

Abstract Background Serine hydroxymethyltransferase 2 (SHMT2) is a vital metabolic enzyme, which catalyzes the conversion of serine to glycine in one-carbon metabolism. SHMT2 has been reported to play a crucial role in the progression of tumors, but its function in oral squamous cell carcinoma (OSCC) remains unclear.Method SHMT2 expression was analyzed using publicly-available online databases, and assessed using immunohistochemistry staining of collected clinical specimens. The correlation between SHMT2 expression and the cell cycle was predicted through bioinformatic analysis, including weighted gene co-expression network analysis and gene set enrichment analysis. After transfection with siRNA CCK8 assay, Edu staining, flow cytometry, transwell, and wound healing experiments were performed to verify the functional role of SHMT2 in vitro. A stable cell line with SHMT2 silencing was established to detect the oncogenic function of SHMT2 in vivo.Results We found that SHMT2 was up-regulated in OSCC tissues and cell lines, and high level of SHMT2 was significantly linked with a poorer clinical outcome for OSCC patients. Bioinformatic analysis found that SHMT2 was closely related with cell cycle regulation. Down-regulation of SHMT2 effectively suppressed the proliferation rate of OSCC cells, and induced the prolongation of the G1 phase of the cell cycle in vitro. Western blotting found that cell cycle-related regulators such as cyclin-dependent kinase 4 (CDK4) and cyclinD1 expression levels were increased, while the expression levels of the cyclin-dependent kinase inhibitors p21Cip1 and p27Kip1 were decreased after SHMT2 knockdown. Invasive and migrative ability and epithelial mesenchymal transition were impaired by SHMT2 knockdown. Silencing SHMT2 in the HN6 cell line using short hairpin RNA impeded tumor growth in vivo.Conclusion Our findings suggested that high expression of SHMT2 in OSCC indicated low survival rates, and was associated with malignant behaviors of OSCC. SHMT2 may serve as a novel prognostic and therapeutic target of interest in OSCC.


2009 ◽  
Vol 21 (1) ◽  
pp. 194
Author(s):  
N. Mtango ◽  
K. Latham

After fertilization, cell division is required for development during the transition from a zygote to an embryo. Degradation of oocyte transcripts, transcriptional activation of the nucleus, and chromatin remodeling occur during early cleavage divisions. Defects in cell cycle regulation decrease the ability of embryo to grow and can be detrimental. In the rhesus monkey, embryos derived by fertilization of oocytes from prepubertal females or oocytes collected during the non-breeding season undergo cleavage arrest (Schramm and Bavister 1994; Zheng et al. 2001). We employed the Primate Embryo Gene Expression Resource (PREGER; www.Preger.org) to examine the expression pattern of 70 mRNAs involved in cell cycle regulation in rhesus monkey oocytes and embryos derived from different stimulation protocols (non-stimulated, FSH stimulated-in vitro matured, and FSH and hCG stimulated-in vivo matured; Mtango and Latham 2007, 2008; Zheng et al. 2005). The resource encompasses a large, biologically rich set of more than 170 samples with 1 to 4 oocytes or embryos which were constructed using the quantitative amplification and dot blotting method. This method entails the direct lysis of small numbers of oocytes or embryos in a reverse transcription buffer supplemented with nonionic detergent, thereby avoiding RNA losses associated with organic extractions (Brady and Iscove 1993). We find that aberrant regulation of cell cycle regulatory gene mRNAs is a prominent feature of oocytes and embryos of compromised developmental potential (FSH stimulated-moderate reduced potential and NS-severely compromised potential). Of the 56 mRNAs for which expression was detected, there was significant aberrations related to oocyte and embryo quality in the expression of more than half (n = 30), P < 0.05), 26 of 30 display significant differences in metaphase II stage oocytes, 20 being altered in FSH stimulated females and 24 of 30 being altered in NS females. The comparison between monkey and previously reported mouse array expression data (Zeng et al. 2004) revealed striking differences between 2 species. These data provide novel information about disruptions in the expression of genes controlling the cell cycle in oocytes and embryos of compromised developmental potential. We thank Bela Patel, Malgorzata McMenamin, and Ann Marie Paprocki for their technical assistance. We also thank R. Dee Schramm for his contribution to the development of the PREGER resource. This work was supported by National Centers for Research Resources Grant RR-15253.


2019 ◽  
Vol 97 (5) ◽  
pp. 589-599 ◽  
Author(s):  
Jie Yang ◽  
Fan Yu ◽  
Jinlei Guan ◽  
Tao Wang ◽  
Changjiang Liu ◽  
...  

A previous study has reported that knockdown of RING finger protein 2 (RNF2) increases the radiosensitivity of esophageal cancer cells both in vitro and in vivo. However, the effect of RNF2 knockdown on radiosensitivity in squamous cell carcinoma (SqCC) remains unknown. For this, NCI-H226 and SK-MES-1 cells were exposed to X-ray irradiation and then RNF2 levels were determined. RNF2 was knocked-down and stable transfectants were selected. Radiosensitivity, cell proliferation, apoptosis, cell cycle, and γ-H2AX foci formation were evaluated. Interaction among ataxia telangiectasia mutated protein (ATM), mediator of DNA damage checkpoint 1 (MDC1), and H2AX were examined. Xenograft models were used to explore the effect of RNF2 knockdown on radiosensitivity in vivo. The results showed that RNF2 expression was significantly increased by X-ray irradiation. RNF2 knockdown combined with X-ray irradiation markedly inhibited cell proliferation, caused cell cycle arrest at the G1 phase, and induced cell apoptosis. In addition, RNF2 knockdown enhanced the radiosensitivity of SqCC cells, inhibited irradiation-induced γ-H2AX foci formation, and impaired the interactions among ATM, MDC1, and H2AX. Furthermore, combination of RNF2 knockdown and X-ray irradiation suppressed tumor growth and promoted tumor cell apoptosis in vivo. RNF2 may be a new therapeutic target to enhance the radiosensitivity of SqCC cells in lung.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4790-4790
Author(s):  
Paola Neri ◽  
Teresa Calimeri ◽  
Mariateresa Di Martino ◽  
Marco Rossi ◽  
Orietta Eramo ◽  
...  

Abstract Valproic acid (VPA) is a well-tolerated anticonvulsant drug that has been recently recognized as powerful histone deacetylase (HDCA) inhibitor. VPA induces hyperacetylation of histone H3 and H4 and inhibits both class I and II HDCACs. Recently it has been shown that VPA exerts in vitro and in vivo anti-tumor activity against solid cancers and its in vitro anti-Multiple Myeloma (MM) activity has been previously reported. However, the molecular mechanisms are still unclear. Here we have investigated molecular changes induced by VPA as well as its in vivo activity in murine models of MM. We first studied the in vitro activity of VPA against IL-6 independent as well as IL-6 dependent MM cells. A time- and dose-dependent decrease in proliferation and survival of MM cell lines was observed (IC50 in the range of 1–3 mM). Gene expression profile following treatment with VPA at 2 and 5 mM showed down-regulation of genes involved in cell cycle regulation, DNA replication and transcription as well as up-regulation of genes implicated in apoptosis and chemokine pathways. The signaling pathway analysis performed by Ingenuity Systems Software identified the cell growth, cell cycle, cell death as well as DNA replication and repair as the most important networks modulated by VPA treatment. We next evaluated the in vivo activity of VPA using two xenograft models of human MM. A cohort of SCID mice bearing subcutaneous MM1s or OPM1 were treated i.p. daily with VPA (200 mg/kg, and 300 mg/kg, n=5 mice, respectively), or vehicle alone (n=5 mice) for 16 consecutive days. Tumors were measured every 2 days, and survival was calculated using the Kaplan Mayer method. Following VPA treatment, we found a significant (p=0.006) inhibition of tumor growth in mice bearing subcutaneous MM-1s cells treated with VPA at 200 mg/kg compared to control group, which translated into a significant (p= 0.002) survival advantage in the VPA treated animals. Similar results were obtained in animals bearing subcutaneous OPM1 cells. Flow cytometry analysis performed on retrieved tumor tissues from animals showed reduction of G2-M and S phase in tumor specimens following VPA treatment, versus untreated tumors, strongly suggesting in vivo effects of VPA on cell cycle regulation. Taken together, our data demonstrate the in vitro and in vivo anti-tumor activity of VPA, delineate potential molecular targets triggered by this agent and provide a preclinical rationale for its clinical evaluation, both as a single agent or in combination, to improve patient outcome in MM.


2021 ◽  
Author(s):  
Xinning Liu ◽  
Yanan Jiang ◽  
Hao Zhou ◽  
Mingzhu Li ◽  
Zhuo Bao ◽  
...  

Abstract Background: Esophageal squamous cell carcinoma (ESCC) is a high recurrence rate of upper-digestive cancer with a low 5-year survival rate. Therefore, there is an urgent need for effective chemopreventive drugs that can extend the survival rate of patients. Through screening of FDA-approved drugs, dasabuvir was found to suppress ESCC proliferation. Methods: Cell number count assay was used to screen for drugs with inhibitory effect on ESCC cells and detect the inhibitory effect of dasabuvir on proliferation of ESCC cells KYSE150 and KYE450. Phosphoproteomics and proteomics were used to investigate the mechanism of dasabuvir inhibiting ESCC. In vitro kinase assay was used to verify the inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) activation by ROCK1 by dasabuvir. The PDX model was used to test the inhibitory effect of dasabuvir on ESCC in vivo.Results: In this study, we found that dasabuvir is a novel inhibitor of Rho-associated protein kinase 1 (ROCK1). Dasabuvir inhibited the growth of the KYSE150 and KYSE450 ESCC cell lines in a time and dose-dependent manner and arrested cell cycle at the G0/G1 phase. The antitumor activity was validated in vivo using a patient-derived xenograft tumor model in mice. Dasabuvir inhibited the activation of ERK1/2 by ROCK1 and downregulated cyclin-dependent kinase 4 (CDK4) and cyclin D1 expression. Conclusions: These results provide the first evidence that dasabuvir serves as a ROCK1 inhibitor, suppresses ESCC growth in vivo and in vitro, and arrests the cell cycle through the ROCK1/ERK signaling pathway.


2018 ◽  
Vol 2 (2) ◽  

Background: Oral cancer is sixth most common cancer in India with poor overall disease free survival. In last decade major changes in the cancer management has happened but no such advantage has been seen in the survival of oral cancer patients. One major reason for the poor survival of head and neck squamous cell carcinoma (HNSCC) is lack of good predictive and prognostic biomarkers. Different studies have shown that in cancer cells, cell-cycle regulatory protein expression is altered. Cyclin D1 is a key regulatory molecule in cell cycle regulation. Many of the molecular alterations that cause abnormal biologic behaviour of cancer cells are based on aberrations of cell cycle regulation. Studies have demonstrated that Cyclin D1, c-Myc and MMP7 were important target genes of WNT signaling pathway and overexpression of them was highly associated with accumulation of β-Catenin and mutational defects of the WNT signaling pathway in numerous tumor types. Aim: This study was planned to characterize the β-Catenin and Cyclin D1 transcript level expression pattern in oral squamous cell carcinoma (OSCC) samples. Materials and Methods: Expression patterns of β-Catenin and Cyclin D1 were studied in OSCC at the transcript and protein levels by using qRT-PCR and immunohistochemistry (IHC) respectively. χ2, t-tests and ANOVA were used for the statistical analyses. Results: β-Catenin and Cyclin D1 were significantly overexpressed in oral squamous cell carcinoma cases when compared to normal. Correlation regression analysis showed the expression of Cyclin D1 and β-Catenin at mRNA level were positively correlated. Further, in immunohistochemical analysis β-Catenin showed cytoplasmic staining rather than nuclear. Conclusion: It is concluded that β-Catenin and Cyclin D1 mRNA level analysis using Real-time PCR could serve as biomarkers in oral squamous cell carcinoma since their expression is consistently altered in majority of the oral squamous cell carcinoma samples.


1996 ◽  
Vol 3 (2) ◽  
pp. 63-66 ◽  
Author(s):  
Lorraine K. Webster ◽  
Silvina Rainone ◽  
Ernst Horn ◽  
Edward R. T. Tiekink

The [Ph3PAu(6-MP)] complex, where 6-MPH is 6-mercaptopurine, is active against the cisplatinresistant cell line, mouse leukaemia L1210/DDP, as is the precursor compound [Ph3PAuCl], suggesting that the thiolate is not critical for activity. Against the human cell lines, FaDu (squamous cell carcinoma) and SKOV-3 (ovarian carcinoma), both [Ph3PAu(6-MP)] and [Ph3PAu(6-TG)], where 6-TGH is 6-thioguanine, were active. [Ph3PAu(6-MP)] was active against a murine PC6 plasmacytoma, but not as active as cisplatin.


Sign in / Sign up

Export Citation Format

Share Document