Growth Of Squamous Cell Carcinoma Research Articles

Tumor Necrosis Factor α–Induced Protein 8–Like 1 Binds to Protein Arginine Methyltransferase 1 to Suppress the Methylation of Signal Transducer and Activator of Transcription 3 and Cell Growth in Oral Squamous Cell Carcinoma

Tumor necrosis factor alpha-induced protein 8 (TIPE/TNFAIP8/OXi-α) family are a newly discovered series of proteins involved in immune regulation and tumorigenesis. TIPE1, as the member of TIPE/TNFAIP8/OXi-α family, has emerged as an anti-cancer drug target as it is promotes cancer cell apoptosis and inhibits cell proliferation. Here, the current study aimed to systematically reveal that TIPE1 regulates the activity of protein arginine methyltransferase 1 (PRMT1) and the subsequent methylation of signal transducer and activator of transcription 3 (STAT3) to suppress oral squamous cell carcinoma (OSCC) growth. Results showed that TIPE1 was down-regulated in the OSCC cell lines (Tca8113, SCC25, Cal27, SCC15 and HSC27). TIPE1 overexpression significantly inhibited cell proliferation, colony formation, in vivo tumorgenicity and Ki67 expression in OSCC. TIPE1 was found to interact with the catalytic region of PRMT1 and inhibited STAT3 methylation. The effects of TIPE1 on OSCC cells were alleviated following PRMT1-overexpression, confirming the importance of this interaction to the tumor suppressive effects of TIPE1. Together, those findings confirmed that TIPE1 mediated PRMT1 suppression through direct binding to its catalytic domain and then inhibits the methylation and expression of STAT3 in OSCC cells, thereby inhibiting cell growth and tumorgenicity.

Cisplatin-resistance induces lung squamous carcinoma cell growth by nicotine-mediated α7nAchR/HDAC1/Cyclin D1/pRb cell cycle activation.

The majority of adenocarcinoma lung cancer is found in nonsmokers. A history of tobacco use is more common in squamous cell carcinoma of the lung. The aim of this study is to identify the cisplatin (CDDP)-resistance that promotes lung squamous carcinoma cell growth through nicotine-mediated HDAC1/7nAchR/E2F/pRb cell cycle activation. Squamous cell carcinoma (NCI-H520 and NCI-H157) cells were examined after cisplatin and nicotine treatment by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay, cell migration assay, immunofluorescence staining, western blot analysis, and immunoprecipitation analysis. Consequently, CDDP is released from DNA and Rb phosphorylated pRb as a result of nicotine-induced cancer cell proliferation through 7nAchR, which then triggers the opening of the HDAC1 cell cycle. The cell cycle is stopped when CDDP adducts are present. Nicotine exerts cancer cytoprotective effects by allowing HDAC1 repair mechanisms to re-establish E2F promoting DNA stimulation cell cycle integrity in the cytosol and preventing potential CDDP and HDAC1 suppressed in the nuclear. Concentration expression of nicotine causes squamous carcinoma cell carcinogens to emerge from inflammation. COX2, NF-KB, and NOS2 increase as a result of nicotine-induced squamous carcinoma cell inflammation. Nicotine enhanced the cell growth-related proteins such as α7nAchR, EGFR, HDAC1, Cyclin D, Cyclin E, E2F, Rb, and pRb by western blot analysis. It also induced cancer cell inflammation and growth. As a result, we suggest that nicotine will increase the therapeutic resistance effects of CDDP. This has the potential to interact with nicotine through α7nAchR receptors and HDAC1/Cyclin D/E2F/pRb potentially resulting in CDDP therapy resistance, as well as cell cycle-induced cancer cell growth.

SENP3 mediates the activation of the Wnt/β-catenin signaling pathway to accelerate the growth and metastasis of oesophagal squamous cell carcinoma in mice.

As a common malignant tumor, esophageal squamous cell carcinoma (ESCC) is occasionally seen in clinical practice. This type of disease has low incidence rate and mortality. The post-translational modification of small ubiquitin like modifiers (SUMO) can play a crucial role in regulating protein function, and can significantly impact the occurrence and development of diseases. SUMO-specific peptidase (SENP) affects cell activity by regulating the biological function of SUMO. SENP3 belongs to the SENP family, and available data indicate that many malignancies are associated with SENPs, it is currently unclear its role in ESCC. This study indicates that there is a high level of SENP3 expression in ESCC tumor cells. If the expression level of this gene is high, it can have a significant impact on ESCC cell lines and affect physiological activities such as invasion of KYSE170 cells. If the gene is knocked out, this situation will not occur. There is also research data indicating that this gene can effectively activate related signaling pathways, thereby promoting the physiological activities of malignant tumor cells. In a nude mouse xenograft tumor model, KYSE170 cells with SENP3 expression knockdown induced a smaller volume and weight of tumor tissue. Therefore, it can be clearly stated that SENP3 can enable Wnt/ β- The catenin signaling pathway is stimulated, which in turn affects the physiological activities of ESCC cells, including the invasion process. The results of this article lay the foundation for clinical staff to carry out clinical management.

Targeting TAOK1 with resveratrol inhibits esophageal squamous cell carcinoma growth in vitro and in vivo.

The worldwide incidence and mortality rates of esophageal squamous cell carcinoma (ESCC) have increased over the last decade. Moreover, molecular targets that may benefit the therapeutics of patients with ESCC have not been fully characterized. Our study discovered that thousand and one amino-acid protein kinase 1 (TAOK1) is highly expressed in ESCC tumor tissues and cell lines. Knock-down of TAOK1 suppresses ESCC cell proliferation in vitro and patient-derived xenograft or cell-derived xenografttumors growth in vivo. Moreover, TAOK1 overexpression promotes ESCC growth in vitro and in vivo. Additionally, we identified that the natural small molecular compound resveratrol binds to TAOK1 directly and diminishes the kinase activity of TAOK1. Targeting TAOK1 directly with resveratrol significantly inhibits cell proliferation, induces cell cycle arrest and apoptosis, and suppresses tumor growth in ESCC. Furthermore, the silencing of TAOK1 or the application of resveratrol attenuated the activation of TAOK1 downstream signaling effectors. Interestingly, combining resveratrol with paclitaxel, cisplatin, or 5-fluorouracil synergistically enhanced their therapeutic effects against ESCC. In conclusion, this work illustrates the underlying oncogenic function of TAOK1 and provides a theoretical basis for the application of targeting TAOK1 therapy to the clinical treatment of ESCC.

The effect of c-Fos on the prognosis, proliferation, and invasion of oral squamous cell carcinoma.

This study aimed to determine the role of c-Fos in growth and invasion of oral squamous cell carcinoma (OSCC). Immunohistochemistry was used to assess c-Fos expression in 94 OSCC tissues and 30 adjacent normal tissues, the correlation between c-Fos expression and clinicopathological characteristics was examined, and Kaplan-Meier and Cox analysis were used to investigate the role of c-Fos in predicting the prognosis of OSCC patients. The effects of c-Fos on the growth and invasion of OSCC were disclosed by overexpression and knockdown of c-Fos. Furthermore, based on bioinformatics prediction, the effect of miR-155-5p on c-Fos expression was examined, and dual-luciferase reporter assay system was used to determine whether miR-155-5p regulated the transcriptional activity of c-Fos in OSCC. c-Fos was markedly increased in OSCC tissues and cells. c-Fos upregulation indicates a poor prognosis in OSCC patients, and c-Fos promotes cell proliferation, migration, and invasion in OSCC. miR-155-5p could regulate the expression and the transcriptional activity of c-Fos by directly targeting the c-Fos 3'-UTR. This study demonstrated that c-Fos contributed to the progression of OSCC and may act as a potential target for OSCC therapy, and a potential prognostic biomarker of OSCC.

Icariin Mitigates the Growth and Invasion Ability of Human Oral Squamous Cell Carcinoma via Inhibiting Toll-Like Receptor 4 and Phosphorylation of NF-κB P65 [Retraction

[This retracts the article DOI: 10.2147/OTT.S214514.].

Antiangiogenic Activity of Pineapple (Ananas comosus) Stem Extract on Chicken Embryo’s Chorioallantois Membrane (CAM)

Inhibition of angiogenesis is able to suppress cancer growth by starving the cancer cells. It has been reported that the growth of human tongue squamous cell carcinoma can be inhibited by administering pineapple’s (Ananas comosus) extract. However, antiangiogenic activity of this extract has not been studied yet. This study aimed to investigate antiangiogenic activity of pineapple’s stem extract on chorioallantoic membrane (CAM) of chicken embryo. Pineapple stems were extracted by ultrasonic-assisted method using ethanol 96%. The chemical compositions were determined by thin layer chromatography (TLC) and the protein concentration was analysed by the biuret method. In-ovo antiangiogenics assay was performed on CAM induced by basic fibroblast growth factor (bFGF). The extract at concentrations of 0.6%, 0.9% and 1.2% were administered on days 9-14 of egg incubation. We counted the number of CAM vasculatures using a stereomicroscope and examined the embryonic blood smears-stained May-Grunwald to investigate the extract-induced inflammation. Pineapple extract contained saponin by TLC and 1.93 mg/ml protein by the biuret test. The vasculatures were significantly reduced by all concentrations of the extract. At a concentration of 1.2%, the extract did not induce notable inflammation in chicken embryos. In conclusion, pineapple stems extract shows antiangiogenics activity on CAM.

Corynoline inhibits esophageal squamous cell carcinoma growth via targeting Pim-3

BackgroundEsophageal squamous cell carcinoma (ESCC) is an aggressive and deadly malignancy characterized by late-stage diagnosis, therapy resistance, and a poor 5-year survival rate. Finding novel therapeutic targets and their inhibitors for ESCC prevention and therapy is urgently needed. MethodsWe investigated the proviral integration site for maloney murine leukemia virus 3 (Pim-3) protein levels using immunohistochemistry. Using Methyl Thiazolyl Tetrazolium and clone formation assay, we verified the function of Pim-3 in cell proliferation. The binding and inhibition of Pim-3 by corynoline were verified by computer docking, pull-down assay, cellular thermal shift assay, and kinase assay. Cell proliferation, Western blot, and a patient-derived xenograft tumor model were performed to elucidate the mechanism of corynoline inhibiting ESCC growth. Results: Pim-3 was highly expressed in ESCC and played an oncogenic role. The augmentation of Pim-3 enhanced cell proliferation and tumor development by phosphorylating mitogen-activated protein kinase 1 at T185 and Y187. The deletion of Pim-3 induced apoptosis with upregulated cleaved caspase-9 and lower Bcl2 associated agonist of cell death phosphorylation at S112. Additionally, binding assays demonstrated corynoline directly bound with Pim-3, inhibiting its activity, and suppressing ESCC growth. ConclusionsOur findings suggest that Pim-3 promotes ESCC progression. Corynoline inhibits ESCC progression through targeting Pim-3.

Butein inhibits oral squamous cell carcinoma growth via promoting MCL-1 ubiquitination.

Oral squamous cell carcinoma (OSCC) is the most common malignant head and neck carcinoma type. Myeloid cell leukemia-1 (MCL-1), an anti-apoptotic BCL-1 protein, has been verified to be among the most highly upregulated pathologic proteins in human cancers linked to tumor relapse, poor prognosis and therapeutic resistance. Herein, therapeutic targeting MCL-1 is an attractive focus for cancer treatment. The present study found that butein, a potential phytochemical compound, exerted profound antitumor effects on OSCC cells. Butein treatment significantly inhibited cell viability, proliferation capacity and colony formation ability, and activated cell apoptotic process. Further potential mechanism investigation showed that promoting MCL-1 ubiquitination and degradation is the major reason for butein-mediated OSCC cell cytotoxicity. Our results uncovered that butein could facilitate E3 ligase FBW7 combined with MCL-1, which contributed to an increase in the ubiquitination of MCL-1 Ub-K48 and degradation. The results of both in vitro cell experiments and in vivo xenograft models imply a critical antitumor function of butein with the well-tolerated feature, and it might be an attractive and promising agent for OSCC treatment.

Role of rs2366152 single-nucleotide variant located in the long noncoding RNA HOTAIR gene in the cervical cancer susceptibility in a Polish population.

Previous studies have demonstrated an association of the NC_000012.12:g.53962605A > G, (rs2366152) single-nucleotide variant (SNV) situated in the long noncoding homeobox transcript antisense intergenic RNA (HOTAIR) gene with HPV16-related cervical cancer pathogenesis. However, little is known about the role of rs2366152 in cervical cancer progression and how oral birth control pills use, parity, menopausal status, and cigarette smoking influence the role of rs2366152 in cervical carcinogenesis. HRM analysis was used to determine the rs2366152 SNV prevalence in patients with cervical squamous cell carcinoma (SCC) (n = 470) and control group (n = 499) in a Polish Caucasian population. Logistic regression analyses were adjusted for age, using birth control pills, parity, menopausal status, and cigarette smoking. Our genetic studies revealed that the G/A vs. A/A (p = 0.031, p = 0.002) and G/A + G/G vs. A/A (p = 0.035, p = 0.003) genotypes of rs2366152 SNV were significantly related to the grade of differentiation G3 and tumor stage III, respectively. Moreover, cervical cancer risk increased among patients with rs2366152 SNV who smoked cigarettes and used birth control pills. We conclude that rs2366152 may promote the invasion and rapid growth of cervical SCC. Moreover, rs2366152 with cigarette smoking and using birth control pills can also be a risk factor for cervical cancerogenesis.

PRI-724 and IWP-O1 Wnt Signaling Pathway Inhibitors Modulate the Expression of Glycolytic Enzymes in Tongue Cancer Cell Lines.

The dysregulation of energetic metabolism is one of the hallmarks of cancer cells. Indeed, the growth of head and neck squamous cell carcinoma (HNSCC) cells depends heavily on glycolytic activity, which can be considered a potential therapeutic target. Wnt signaling is one of the pathways that undergoes upregulation in HNSCC. Our previous studies have shown that Wnt signaling inhibitors-PRI-724 and IWP-O1-attenuate tongue SCC survival and reduce glucose uptake and lactate release. The aim of this research was to further evaluate the possible mechanisms of the previously observed effects. We assessed the effect of PRI-724 and IWP-O1 on the expression of selected glycolytic enzymes: phosphofructokinase M, pyruvate kinase M2, and lactate dehydrogenase. Relative transcript expression was assessed by real-time PCR, and protein levels by Western blot. Moreover, clinical data concerning mRNA and protein expression, gene promoter methylation, and HNSCC patients' survival time were analyzed by the UALCAN tool, and protein-protein interaction was assessed using the STRING database. Experimental and bioinformatic data confirmed the relation between Wnt signaling and glycolytic enzymes in tongue cancer cells and HNSCC clinical samples. Overall, the inhibition of glucose metabolism by Wnt signaling inhibitors is a promising mode of action against tongue cancer cells.

Retraction: ET-1 promotes the growth and metastasis of esophageal squamous cell carcinoma via activating PI3K/Akt pathway.

[This retracts the article DOI: 10.21037/tcr.2020.04.26.].

The Expression of PTTG1 as a Biomarker and Impact on Invasion and Growth of Oral Squamous Cell Carcinoma

The Expression of PTTG1 as a Biomarker and Impact on Invasion and Growth of Oral Squamous Cell Carcinoma

Inhibition of TGF-β signaling, invasion, and growth of cutaneous squamous cell carcinoma by PLX8394

Cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer. The prognosis of patients with metastatic cSCC is poor emphasizing the need for new therapies. We have previously reported that the activation of Ras/MEK/ERK1/2 and transforming growth factor β (TGF-β)/Smad2 signaling in transformed keratinocytes and cSCC cells leads to increased accumulation of laminin-332 and accelerated invasion. Here, we show that the next-generation B-Raf inhibitor PLX8394 blocks TGF-β signaling in ras-transformed metastatic epidermal keratinocytes (RT3 cells) harboring wild-type B-Raf and hyperactive Ras. PLX8394 decreased phosphorylation of TGF-β receptor II and Smad2, as well as p38 activity, MMP-1 and MMP-13 synthesis, and laminin-332 accumulation. PLX8394 significantly inhibited the growth of human cSCC tumors and in vivo collagen degradation in xenograft model. In conclusion, our data indicate that PLX8394 inhibits several serine-threonine kinases in malignantly transformed human keratinocytes and cSCC cells and inhibits cSCC invasion and tumor growth in vitro and in vivo. We identify PLX8394 as a potential therapeutic compound for advanced human cSCC.

CircSSPO boosts growth of esophageal squamous cell carcinoma through upregulation of micrRNA-6820-5p-mediated KLK8 and PKD1 expression.

Investigation on a competitive endogenous RNA (ceRNA) network attracted lots of attention due its function in cancer regulation. Here, we probed into the possible molecular mechanism of circSSPO/microRNA-6820-5p (miR-6820-5p)/kallikrein-related peptidase 8 (KLK8)/PKD1 network in the esophageal squamous cell carcinoma (ESCC). Following whole-transcriptome sequencing and differential analysis in collected ESCC tissue samples, circRNA-miRNA-mRNA regulatory network affecting ESCC was investigated. After interaction measurement among circSSPO/miR-6820-5p/KLK8/PKD1, their regulatory roles in ESCC cell functions in vitro and xenograft tumor growth and lung metastasis in vivo were analyzed. The bioinformatics prediction and sequencing results screened that circSSPO, miR-6820-5p, KLK8, and PKD1 were associated with ESCC development. In ESCC, miR-6820-5p was expressed at very low levels, while circSSPO, KLK8, and PKD1 were highly expressed. In vitro cell experiments further proved that circSSPO competitively inhibited miR-6820-5p to induce ESCC cell malignant properties. Moreover, knockdown of KLK8 or PKD1 inhibited ESCC cell malignant properties. circSSPO also promoted the tumorigenic and metastasis of ESCC through the upregulation of KLK8 and PKD1 expression in vivo. We found that circSSPO was an oncogenic circRNA that was significantly abundant in ESCC tissues and circSSPO exhibited an oncogenic activity in ESCC by elevating expression of KLK8 and PKD1 through suppressing miR-6820-5p expression.

PTP4A1 promotes oral squamous cell carcinoma (OSCC) metastasis through altered mitochondrial metabolic reprogramming

PTP4A1 (Protein tyrosine phosphatase 4A1) is a protein tyrosine phosphatase that regulates a range of pro-oncogenic signaling pathways. Here, we report a novel role for PTP4A1 in oral squamous cell carcinoma (OSCC) growth and development. We show that PTP4A1 is frequently overexpressed in OSCC cells and tissues compared to adjacent non-tumor tissue. In OSCC, the overexpression of PTP4A1 increased cell growth and invasion in vitro, and enhanced tumor progression in vivo. At the molecular level, PTP4A1 was found to regulate mitochondrial metabolic reprogramming to enhance the invasive capacity of OSCC cells. Mechanistically, these effects were mediated through binding to pyruvate kinase isoenzyme M2 (PKM2) to promote its expression and aconitase 2 (ACO2) to enhance its degradation. Together, these data reveal PTP4A1 as a viable target for OSCC therapeutics.

Investigating the Role of MK2 in Head and Neck Squamous Cell Carcinoma Growth, Metastasis and STING Pathway Activation

Our prior work demonstrated that inhibition of MAPKAPK2 (MK2) can enhance radiation (RT)-mediated in vivo head and neck squamous cell carcinoma (HNSCC) tumor control and survival in preclinical immune incompetent models. The cytosolic DNA sensor cyclic GMP-AMP synthetase (cGAS) and its downstream adaptor protein, stimulator of interferon genes (STING), are conserved proteins within the innate immune signaling pathways and are important for mediating host defense against microbial infection and can play a role in anti-cancer immunity. We hypothesized that loss of MK2 enhances radiation-induced cGAS-STING pathway activation leading to improved tumor control and survival. MK2 shRNA knockdown human (Tu167, CAL27) and MK2 Cas9/CRISPR knockout (KO) syngeneic murine (Ly2, MLM3) HNSCC cell lines were treated with 10 Gy irradiation. Micronuclei were quantitated by DAPI-immunofluorescence (IF). Protein changes in cGAS-STING were evaluated by immunoblot. Inflammatory cytokine production including Type I IFNβ1 were evaluated by RT-qPCR. Ly2 and MLM3 cells were orthotopically or flank engrafted into immune competent mice (Balb/c, C57Bl/6, respectively) for animal tumor control-survival studies. Tumor immune cell infiltrate was examined using FACS and immunohistochemistry. Selected drug studies using the MK2 inhibitor, ATI-450, were performed with RT. Loss of MK2 in HNSCC (Tu167, CAL27, Ly2, MLM3) treated with RT led to a significant increase in micronuclei formation compared to control cells. MK2-enhanced micronuclei generation following RT could be inhibited with the actin filament polymerization inhibitor, cytochalasin B. RT treatment of MK2 shRNA cells led to increased cGAS and phospho-STING levels compared to either treatment alone. IFNβ1 levels were significantly higher in HNSCC cell lines treated with RT and with MK2 inhibited by an MK2 inhibitor (ATI-450) or genetic reduction compared to either treatment alone. In-vivo implantation of MLM3 cells into C57Bl/6 comparing control vs MK2 KO tumors treated with ±8 Gy RT demonstrated improved mouse survival favoring RT+MK2 KO over RT, MK2 KO or parental (63, 58, 58.5, 35 days, respectively). FACS analysis of MLM3 WT v KO tumors 3 days post RT showed an overall increase in the number of CD3/CD8 T-cells infiltrating into the tumor in all groups except for parental tumors. Further analysis demonstrated that loss of MK2 reversed CD8 T-cell exhaustion and when combined with radiotherapy led to increased CD8 T-cell activation. Furthermore, activated CD4 and CD8 T cells were reduced in WT+RT cells compared to WT tumors whereas no reduction was seen in the KO or KO+RT. HNSCC tumor MK2 inhibition enhances RT-mediated micronuclei formation and subsequent cGAS-STING-IFNβ1 levels. Loss of HNSCC MK2 leads to increased CD4-CD8 T-cell infiltration into the tumor and this effect is enhanced following RT. Targeting tumor MK2 may facilitate improved tumor control.

Role of tissue markers associated with tumor microenvironment in the progression and immune suppression of oral squamous cell carcinoma.

Head and neck cancers (HNC) continues to dominate major cancers contributing to mortality worldwide. Squamous cell carcinoma is the major type of HNC. Oral Squamous Cell Carcinoma grouped under HNC is a malignant tumor occurring in the oral cavity. The primary risk factors of OSCC are tobacco, alcohol consumption, etc. This review focuses on modulations, mechanisms, growth and differentiation of oral squamous cell carcinoma. Cancer cell surrounds itself with a group of elements forming a favorable environment known as tumor microenvironment (TME). It consists of numerous cells which includes immune cells, blood cells and acellular components that are responsible for the progression, immunosuppression, metastasis and angiogenesis of cancer. This review highlights the most important tissue biomarkers (mTOR, CAF, FOXp3, CD163, CD33, CD34) that are associated with TME cells. mTOR remains as the primary regulator responsible in cancer and its importance towards immune-suppression is highlighted. Tumor-associated macrophages associated with cancer development and its relationship with immunomodulatory mechanism and Tregs, which are potential blockers of immune response and its mechanism and aberrations are discussed. Cancer-associated fibroblasts that are a part of TME and their role in evading the immune response and myeloid derived suppressor cells that have slight control over the immune response and their mechanism in the tumor progression is further explained. These markers have been emphasised as therapeutic targets and are currently in different stages of clinical trials.

Emerging functions and applications of exosomes in oral squamous cell carcinoma.

Oral squamous cell carcinoma is the most common phenotype in pathology, which accounts for 80% of all oral cancers. The therapeutic methods of oral squamous cell carcinoma include surgical excision, chemotherapy, and radiotherapy. Whereas, the high recurrence rate and poor prognosis lead to a 5-year survival rate less than 50%. In order to explore more therapeutic strategies of oral squamous cell carcinoma, the relevant risk factors, mechanisms, and diagnostics are widely detected. The various exosome-mediated biological effects on the development of oral squamous cell carcinoma have drawn lots of attention. Exosomes, a kind of extracellular vesicles secreted from host cells and transferred to other cells, show great potential in the regulations of tumorigenesis, progression, and metastasis on oral squamous cell carcinoma. Moreover, some studies reported that the exosomes could interact with tumor microenvironment and be applied to diagnosis or therapy of oral squamous cell carcinoma. In this work, we will summarize the frontier studies of exosomes in the tumor growth, tumor-associated angiogenesis, invasion, and metastasis of oral squamous cell carcinoma, and then probe the current biological functions and applications of exosomes and exosome-derived materials for the therapeutic strategies of oral squamous cell carcinoma, which would help us to update the understanding of exosomes in oral squamous cell carcinoma.

Thymidylate synthase promotes esophageal squamous cell carcinoma growth by relieving oxidative stress through activating nuclear factor erythroid 2-related factor 2 expression.

Thymidylate synthase (TYMS) is involved in the malignant process of multiple cancers, and has gained much attention as a cancer treatment target. However, the mechanism in carcinogenesis of esophageal squamous cell cancer (ESCC) is little reported. The present study was to clear the biological roles and carcinogenic mechanism of TYMS in ESCC, and explored the possibility to use TYMS as a tumor marker in diagnosis and a drug target for the treatment of ESCC. Stably TYMS-overexpression cells established by lentivirus transduction were used for the analysis of cell proliferation. RNA sequencing was performed to explore the possible carcinogenic mechanisms. GEPIA databases analysis showed that TYMS expression in esophageal cancer tissues was higher than that in normal tissues. The MTT assay, colony formation assay, and nude mouse subcutaneous tumor model found that the overexpression of TYMS increased cell proliferation. Transcriptome sequencing analysis revealed that the promoted cell proliferation in TYMS-overexpression ESCC cells were mediated through activating genes expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and Nrf2 dependent antioxidant enzymes to relieve oxidative stress, which was confirmed by increased glutathione (GSH), glutathione peroxidase (GPX) activities, and reduced reactive oxygen species. Nrf2 active inhibitors (ML385) used in TYMS-overexpression cells inhibited the expression of Nrf2-dependent antioxidant enzyme genes, thereby increasing oxidative stress and blocking cell proliferation. Our study indicated a novel and effective regulatory capacity of TYMS in the cell proliferation of ESCC by relieving oxidative stress through activating expression of Nrf2 and Nrf2-dependent antioxidant enzymes genes. These properties make TYMS and Nrf2 as appealing targets for ESCC clinical chemotherapy.