Glutamine provides carbon and nitrogen to support the proliferation of cancer cells. However, the precise reason why cancer cells are particularly dependent on glutamine remains unclear. In this study, we report that glutamine modulates the tumor suppressor F-box and WD repeat domain-containing 7 (FBW7) to promote cancer cell proliferation and survival. Specifically, lysine 604 (K604) in the sixth of the 7 substrate-recruiting WD repeats of FBW7 undergoes glutaminylation (Gln-K604) by glutaminyl tRNA synthetase. Gln-K604 inhibits SCFFBW7-mediated degradation of c-Myc and Mcl-1, enhances glutamine utilization, and stimulates nucleotide and DNA biosynthesis through the activation of c-Myc. Additionally, Gln-K604 promotes resistance to apoptosis by activating Mcl-1. In contrast, SIRT1 deglutaminylates Gln-K604, thereby reversing its effects. Cancer cells lacking Gln-K604 exhibit overexpression of c-Myc and Mcl-1 and display resistance to chemotherapy-induced apoptosis. Silencing both c-MYC and MCL-1 in these cells sensitizes them to chemotherapy. These findings indicate that the glutamine-mediated signal via Gln-K604 is a key driver of cancer progression and suggest potential strategies for targeted cancer therapies based on varying Gln-K604 status.
Glutamine/metabolism* ; Myeloid Cell Leukemia Sequence 1 Protein/genetics* ; Humans ; Proto-Oncogene Proteins c-myc/genetics* ; Cell Proliferation ; Signal Transduction ; Neoplasms/pathology* ; F-Box-WD Repeat-Containing Protein 7/genetics* ; Cell Survival ; Cell Line, Tumor ; Apoptosis

Objective To investigate the effect of insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) on the proliferation, migration and tumor immune microenvironment of colorectal cancer cells and its possible molecular mechanism. Methods The Cancer Genome Atlas (TCGA) database was used to analyze the expression levels of IGF2BP2 and MYC in colorectal cancer and adjacent tissues. The expression of IGF2BP2 in HCT-116 and SW480 human colorectal cancer cells was silenced by RNA interference (RNAi), and the silencing effect was detected by quantitative real-time PCR. After knocking down IGF2BP2, colony formation assay, CCK-8 assay and 5-ethynyl-2'-deoxyuridine (EdU) assay were employed to detect cell colony formation and proliferation ability. Transwell^TM assay was used to detect cell migration ability. Quantitative real-time PCR was used to detect the mRNA expression of IGF2BP2, MYC, tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β) and interleukin-10 (IL-10). The protein expression of IGF2BP2 and MYC was detected by western blot. The binding ability of IGF2BP2 and MYC in HCT-116 cells was detected by quantitative real-time PCR after RNA immunoprecipitation. Results The results of TCGA database showed that the expression of IGF2BP2 and MYC in colorectal cancer tissues was significantly higher than that in adjacent tissues, and the survival time of colorectal cancer patients with high expression of IGF2BP2 was shorter. After silencing IGF2BP2, the viability, proliferation and migration of HCT-116 and SW480 cells were decreased. The mRNA expression of MYC, TGF-β and IL-10 in IGF2BP2 knockdown group was significantly decreased, while the expression of TNF-α mRNA was increased. The expression of MYC protein and the stability of MYC mRNA were significantly decreased. RIP-qPCR results showed that IGF2BP2 could bind to MYC mRNA. Conclusion Knockdown of IGF2BP2 inhibits colorectal cancer cell proliferation, migration and promotes tumor immunity by down-regulating MYC expression.
Humans ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Colorectal Neoplasms/metabolism* ; Gene Expression Regulation, Neoplastic ; Interleukin-10/metabolism* ; RNA, Messenger ; RNA-Binding Proteins/metabolism* ; Transforming Growth Factor beta/genetics* ; Tumor Microenvironment/immunology* ; Tumor Necrosis Factor-alpha/metabolism* ; Proto-Oncogene Proteins c-myc/metabolism*

OBJECTIVES: Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor of head and neck. Screening of target genes for malignant tumor therapy is one of the focuses of cancer research, with proto-oncogene and tumor suppressor gene as the breakthrough. It has become an urgent need to find the target gene related to the treatment and prognosis of LSCC.This study aims to explore the role of Lin28B and C-myc in LSCC by detecting the expressions of these two proteins and analyze the correlation between the expression of Lin28B and C-myc and clinicopathological features and prognosis of LSCC. METHODS: We detected the expression of Lin28B and C-myc proteins in 102 specimens of LSCC and 90 specimens of adjacent tissues by immunochemistry, and analyzed the correlation between Lin28B and C-myc protein expressions in LSCC as well as the correlation between the expressions of the two proteins and the clinicopathological features of LSCC. At the same time, the Kaplan-Meier method was used to analyze the relation between Lin28B and C-myc protein levels with the postoperative survival rate of LSCC patients. RESULTS: The protein levels of Lin28B and C-myc in the LSCC tissnes were significantly higher than those in the adjacent tissues (both P<0.05),and there was a positive correlation between the expression of Lin28B and C-myc in LSCC (r＝0.476, P<0.05). The expression of Lin28B protein was closely related to age, lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). while the expression of C-myc protein was closely related to lymph node metastasis, clinical stage, tumor size, and pathological differentiation of LSCC patients (all P<0.05). A relevant survival analysis showed that in patients with higher level of Lin28B (P＝0.001) or C-myc protein (P<0.001), the postoperative survival rate was relatively low. CONCLUSIONS Lin28B and C-myc proteins are highly expressed in LSCC with a positive correlation. Furthermore, they are closely related to lymph node metastasis, clinical stage, tumor size, pathological differentiation and prognosis, suggesting that both Lin28B and C-myc might be involved in the occurrence and development of LSCC.
Humans ; Squamous Cell Carcinoma of Head and Neck ; Proto-Oncogene Proteins c-myc/metabolism* ; Laryngeal Neoplasms/diagnosis* ; Carcinoma, Squamous Cell/genetics* ; Lymphatic Metastasis ; Prognosis ; Head and Neck Neoplasms ; Biomarkers, Tumor/metabolism* ; RNA-Binding Proteins/genetics*

Glioblastoma is the most common primary cranial malignancy, and chemotherapy remains an important tool for its treatment. Sanggenon C(San C), a class of natural flavonoids extracted from Morus plants, is a potential antitumor herbal monomer. In this study, the effect of San C on the growth and proliferation of glioblastoma cells was examined by methyl thiazolyl tetrazolium(MTT) assay and 5-bromodeoxyuridinc(BrdU) labeling assay. The effect of San C on the tumor cell cycle was examined by flow cytometry, and the effect of San C on clone formation and self-renewal ability of tumor cells was examined by soft agar assay. Western blot and bioinformatics analysis were used to investigate the mechanism of the antitumor activity of San C. In the presence of San C, the MTT assay showed that San C significantly inhibited the growth and proliferation of tumor cells in a dose and time-dependent manner. BrdU labeling assay showed that San C significantly attenuated the DNA replication activity in the nucleus of tumor cells. Flow cytometry confirmed that San C blocked the cell cycle of tumor cells in G_0/G_1 phase. The soft agar clone formation assay revealed that San C significantly attenuated the clone formation and self-renewal ability of tumor cells. The gene set enrichment analysis(GSEA) implied that San C inhibited the tumor cell division cycle by affecting the myelocytomatosis viral oncogene(MYC) signaling pathway. Western blot assay revealed that San C inhibited the expression of cyclin through the regulation of the MYC signaling pathway by lysine demethylase 4B(KDM4B), which ultimately inhibited the growth and proliferation of glioblastoma cells and self-renewal. In conclusion, San C exhibits the potential antitumor activity by targeting the KDM4B-MYC axis to inhibit glioblastoma cell growth, proliferation, and self-renewal.
Humans ; Glioblastoma/genetics* ; Bromodeoxyuridine/therapeutic use* ; Signal Transduction ; Proto-Oncogene Proteins c-myc/metabolism* ; Agar ; Cell Proliferation ; Cell Line, Tumor ; Apoptosis ; Jumonji Domain-Containing Histone Demethylases/metabolism*

In recent years, liver fibrosis has become a hotspot in the field of liver diseases. MicroRNA(miRNA)-mediated Nod-like receptor pyrin domain containing 3(NLRP3) inflammasome activation is pivotal in the pathogenesis of liver fibrosis. The present study mainly discussed the role of miRNA-mediated NLRP3 inflammasome activation in the pathogenesis of liver fibrosis. Different miRNA molecules regulated liver fibrosis by mediating NLRP3 inflammasome activation, including miRNA-350-3 p(miR-350-3 p)/interleukin-6(IL-6)-mediated signal transducer and activator of transcription 3(STAT3)/c-myc signaling pathway, miR-148 a-induced autophagy and apoptosis of hepatic stellate cells via hedgehog signaling pathway, miR-155-mediated NLRP3 inflammasome by the negative feedback of the suppressor of cytokine signaling-1(SOCS-1), miR-181 a-mediated downstream NLRP3 inflammatory pathway activation through mitogen-activated protein kinase kinase(MEK)/extracellular signal-regulated kinase(ERK)/nuclear transcription factor κB(NF-κB) inflammatory pathway, miR-21-promoted expression of NF-κB and NLRP3 of RAW264.7 cells in mice by inhibiting tumor necrosis factor-α inducible protein 3(A20), and miR-20 b-promoted expression of IL-1β and IL-18 by activating NLRP3 signaling pathway. Additionally, the anti-liver fibrosis mechanism of different active components in Chinese medicines(such as Curcumae Rhizoma, Glycyrrhizae Radix et Rhizoma, Aurantii Fructus, Polygoni Cuspidati Rhizoma et Radix, Moutan Cortex, Paeoniae Radix Alba, Epimedii Folium, and Cinnamomi Cortex) was also explored based on the anti-liver fibrosis effect of miRNA-mediated NLRP3 inflammasome activation.
Animals ; Hedgehog Proteins ; Inflammasomes/metabolism* ; Interleukin-6 ; Liver Cirrhosis/metabolism* ; Medicine, Chinese Traditional ; Mice ; MicroRNAs/genetics* ; NF-kappa B/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Proto-Oncogene Proteins c-myc/metabolism* ; Signal Transduction

OBJECTIVE: To investigate the expression and correlation of miR-211, miR-155, and C-myc in acute T lymphocytic leukemia (T-ALL), aiming to provide evidence for the diagnosis and treatment. METHODS: A total of 96 T-ALL patients who were diagnosed and treated in People's Hospital of Zhengzhou from June 2014 to June 2017 were selected, and 69 healthy volunteers who had a physical examination were selected as control group in the same period. Real-time fluorescent quantitative PCR (RT-PCR) was used to determine the expression levels of miR-211, miR-155, and C-myc in peripheral blood mononuclear cells in each group. Kaplan-Meier was used to analyze the survival of T-ALL patients and correlation of miR-211, miR-155, and C-myc with prognosis. Pearson correlation analysis was used to evaluate the correlation of miR-211, miR-155, and C-myc with disease risk. RESULTS: The expression levels of miR-211 mRNA, miR-155 mRNA, and C-myc mRNA in T-ALL group were higher than those in the control group (P<0.01), those in non-remission group were higher than those in remission group (P<0.01), and those in high-risk group were also higher than those in low-risk group and intermediate-risk group (P<0.01). The survival time of T-ALL patients with low miR-211 expression was longer than that with high miR-211 expression (P<0.01), that with low miR-155 expression was longer than that with high miR-155 expression (P<0.01), and that with low C-myc expression was also longer than that with high C-myc expression (P<0.01). The high expression of miR-211, miR-155, and C-myc was linearly positively correlated with high risk of disease (r=0.749, 0.781, 0.804). CONCLUSION The expressions of miR-211, miR-155, and C-myc are up-regulated in T-ALL patients, closely related to prognosis, and linearly positively correlated with disease risk.
Humans ; Leukocytes, Mononuclear ; MicroRNAs/genetics* ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Prognosis ; Proto-Oncogene Proteins c-myc/genetics* ; RNA, Messenger

Objective: To investigate the clinicopathological characteristics and prognosis of high-grade B-cell lymphoma (HGBL) involving combined rearrangements of MYC, bcl-2 and bcl-6. Methods: A total of 1 138 cases of large B cell lymphoma (LBL) that were treated at the Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from January 2017 to September 2020 were analyzed using fluorescence in situ hybridization (FISH) with probes against MYC, bcl-2 and bcl-6. The clinical and pathological data of the 45 patients with HGBL that had rearrangements of MYC and bcl-2 and/or bcl-6 were collected and retrospectively analyzed. Results: Among the 1 138 LBL, 45 (4.0%) cases had combined rearrangements of MYC, bcl-2 and/or bcl-6 that included 6 HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, 14 HGBL cases with MYC and bcl-2 rearrangements, and 25 HGBL cases with MYC and bcl-6 rearrangements. Of these 45 patients, 29 patients were male, and 16 patients were female, aged 29 to 83 years. HGBL with MYC, bcl-2 and bcl-6 rearrangements and HGBL with MYC and bcl-2 rearrangement were reclassified as the germinal center B-cell (GCB) subtype using the Hans algorithm. HGBL with MYC and bcl-6 rearrangement were reclassified as the GCB subtype (68.0%) and the non-GCB subtype (32.0%). The vast majority of HGBL cases had a high Ki-67 proliferation index. Most HGBL patients had advanced stage disease with a high IPI score and an increased LDH level. Also, some patients had clinical features including elevated plasma β2-microglobulin levels, B symptoms, and bone marrow involvement. The IPI scores and LDH levels were significantly different between the HGBL cases with MYC, bcl-2 and bcl-6 rearrangements and the HGBL cases with MYC and bcl-6 rearrangements (P<0.05). Compared with the HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, the HGBL cases with MYC and bcl-2 or bcl-6 rearrangements had a lower incidence of bone marrow involvement (P<0.05). There were no significant differences in the prognosis among HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, the cases with MYC and bcl-2 rearrangements, and the cases with MYC and bcl-6 rearrangements (P>0.05). Conclusions: HGBL with MYC, bcl-2 and/or bcl-6 rearrangements are rare types of B-cell lymphoma with high degree of malignancy and have a short overall survival. To reduce misdiagnosis and improve diagnostic accuracy, it is necessary to assess the patients' clinical features and conduct histopathological, immunohistochemical and FISH analyses.
Adult ; Aged ; Aged, 80 and over ; China ; Female ; Gene Rearrangement ; Humans ; In Situ Hybridization, Fluorescence ; Lymphoma, Large B-Cell, Diffuse/genetics* ; Male ; Middle Aged ; Prognosis ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Proto-Oncogene Proteins c-bcl-6/genetics* ; Proto-Oncogene Proteins c-myc/genetics* ; Retrospective Studies

Cell Line, Tumor ; Cell Proliferation ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs/genetics* ; Proto-Oncogene Proteins c-myc/metabolism* ; RNA, Messenger/genetics* ; Transcription Factors/genetics*

Synthetic lethal screening, which exploits the combination of mutations that result in cell death, is a promising method for identifying novel drug targets. This method provides a new avenue for targeting "undruggable" proteins, such as c-Myc. Here, we revisit current methods used to target c-Myc and discuss the important functional nodes related to c-Myc in non-oncogene addicted network, whose inhibition may cause a catastrophe for tumor cell destiny but not for normal cells. We further discuss strategies to identify these functional nodes in the context of synthetic lethality. We review the progress and shortcomings of this research field and look forward to opportunities offered by synthetic lethal screening to treat tumors potently.
Humans ; Mutation ; Neoplasms/genetics* ; Proteins ; Proto-Oncogene Proteins c-myc/genetics* ; Synthetic Lethal Mutations

Objective: To investigate the strong expression (S+) of P53 and BCL2 proteins in MYC/BCL2 double-expression DLBCL (DEL) and whether they can be used for the prognostic evaluation and stratified diagnosis of DELs. Methods: Tissue microarray were made by filed FFPE blocks of 174 DLBCL cases. The translocation of MYC, BCL2 and BCL6 genes were detected by FISH, and the proteins were detected by IHC. Data of clinicopathologic features and follow up of patients were collected and OS (overall survival) and PFS (progression free survival) were analyzed by statistics. Results: Eight double-hit lymphomas (DHLs) were identified in all cases, and 45 DELs were selected from 166 remaining cases, which have no significant difference in OS and PFS compared with non-DEL cases (P=0.668 and P=0.790) . Of 42 DEL-cases with follow up data, 24 cases with P53+ or/and BCL2 (S+) are significantly shorter OS and PFS than others (P=0.003 and P=0.000) , in which the cases with P53+/BCL2 (S+) co-expression were the worst prognosis, and P53/BCL2 co-weaker positive DEL cases even have superior OS and PFS than those non-DELs. Although statistics showed that the cases of P53+ or/and BCL2 (S+) have a lower OS and PFS in total cases (P=0.063 and P=0.024) , it is not the case when the DEL-cases take out from total cases, that is the cases with P53+ or/and BCL2 (S+) are as similar OS and PFS as others in non-DEL group (P=0.590 and P=0.550) . Conclusion: The strong expression of P53 and BCL2 proteins can be used as indicators of stratified diagnosis and poor prognosis of DEL.
Humans ; Lymphoma, Large B-Cell, Diffuse/genetics* ; Prognosis ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Proto-Oncogene Proteins c-myc/genetics* ; Tumor Suppressor Protein p53/genetics*