R-CHOP and consolidation radiotherapy for limited-stage and low-IPI high-grade b-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements: A single-center case series and review of literature

@#High-Grade B-Cell Lymphoma (HGBCL) with gene rearrangements in MYC and BCL2 and/or BCL6 is an aggressive malignancy usually presenting in advanced stages. Current recommendations suggest the use of regimens more intensive than R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin, prednisone), which are based on retrospective studies and single-arm prospective trials that included patients who are mostly in the advanced stage, and did not receive consolidation radiotherapy. The optimal approach and treatment of HGBCL, whether limited-stage (LS) or advanced-stage, remains to be determined. Here we describe the promising outcomes of three patients with LS and low IPI HGBCL with the use of R-CHOP as induction chemotherapy regimen, which was followed by consolidation radiotherapy. Three women, 54-, 60-, and 64-years of age diagnosed to have HGBCL with MYC, and BCL2 and/or BCL6 rearrangements, with Ann Arbor stages I-IIE were included in this case series. All three patients had complete metabolic response to 6 cycles of R-CHOP and was subsequently treated with consolidation involved site radiotherapy (ISRT; total dose 30-36 Gy). Chemotherapy and radiotherapy were tolerated very well. All patients remain to be in remission, with the longest being at 23 months. Outcomes of patients with HGBCL generally remain to be poor, but this may not be the case for patients with limited-stage disease and favorable clinicopathologic risk profile. Nevertheless, the treatment of HGBCL is currently evolving and more studies are needed to determine the ideal approach and preferred chemotherapy regimen. Also, more studies are needed to elucidate the potential role of consolidation radiotherapy in patients with limited-stage HGBCL to improve survival outcomes. Findings of this case series suggest that patients with LS HGBCL may still derive benefit from R-CHOP followed by consolidation ISRT, but prospective trials are needed to confirm this.

High expression of MYH9 inhibits apoptosis of non-small cell lung cancer cells through activating the AKT/c-Myc pathway / 南方医科大学学报

OBJECTIVE@#To investigate the role of myosin heavy chain 9 (MYH9) in regulation of cell proliferation, apoptosis, and cisplatin sensitivity of non-small cell lung cancer (NSCLC).@*METHODS@#Six NSCLC cell lines (A549, H1299, H1975, SPCA1, H322, and H460) and a normal bronchial epithelial cell line (16HBE) were examined for MYH9 expression using Western blotting. Immunohistochemical staining was used to detect MYH9 expression in a tissue microarray containing 49 NSCLC and 43 adjacent tissue specimens. MYH9 knockout cell models were established in H1299 and H1975 cells using CRISPR/Cas9 technology, and the changes in cell proliferation cell were assessed using cell counting kit-8 (CCK8) and clone formation assays; Western blotting and flow cytometry were used to detect apoptosis of the cell models, and cisplatin sensitivity of the cells was evaluated using IC50 assay. The growth of tumor xenografts derived from NSCLC with or without MYH9 knockout was observed in nude mice.@*RESULTS@#MYH9 expression was significantly upregulated in NSCLC (P < 0.001), and the patients with high MYH9 expression had a significantly shorter survival time (P=0.023). In cultured NSCLC cells, MYH9 knockout obviously inhibited cell proliferation (P < 0.001), promoted cell apoptosis (P < 0.05), and increased their chemosensitivity of cisplatin. In the tumor-bearing mouse models, the NSCLC cells with MYH9 knockout showed a significantly lower growth rate (P < 0.05). Western blotting showed that MYH9 knockout inactivated the AKT/c- Myc axis (P < 0.05) to inhibit the expression of BCL2- like protein 1 (P < 0.05), promoted the expression of BH3- interacting domain death agonist and the apoptosis regulator BAX (P < 0.05), and activated apoptosis-related proteins caspase-3 and caspase-9 (P < 0.05).@*CONCLUSION@#High expression of MYH9 contributes to NSCLC progression by inhibiting cell apoptosis via activating the AKT/c-Myc axis.

LINC00462 regulates clear renal cell carcinoma cells sensitivity to cisplatin by affecting their glycolysis via the MYC/ABCC3 axis / 中国肿瘤生物治疗杂志

@#[摘 要] 目的：探讨LINC00462招募转录因子MYC激活ABCC3对肾透明细胞癌（ccRCC）顺铂敏感性的影响及其机制。方法：数据库分析ccRCC组织中ABCC3、MYC和LINC00462的表达及其相关性，并分析ABCC3基因的富集通路。常规培养人肾小管上皮细胞（HK-2）和ccRCC细胞（A-498、786-O和Caki-2），将si-LINC00462、oe-ABCC3、si-ABCC3、si-MYC、si-LINC00462-NC、oe-ABCC3-NC、si-ABCC3-NC和si-MYC-NC核酸序列分别转染A-498或786-O细胞，分为si-LINC00462组、si-LINC00462-NC组、oe-ABCC3组、oe-ABCC3-NC组、si-ABCC3组、si-ABCC3-NC组、si-MYC组、si-MYC-NC组；用2-脱氧-D-葡萄糖（2-DG）进行回复实验，构建oe-NC+PBS组、oe-ABCC3+PBS组、oe-ABCC3+2-DG组；为探究ccRCC细胞LINC00462/MYC/ABCC3轴对顺铂敏感性的影响，构建si-NC+oe-NC组、si-LINC00462+oe-NC组、si-LINC00462+oe-ABCC3组。qPCR法检测ABCC3、MYC和LINC00462在ccRCC细胞中的表达，CCK-8法检测细胞增殖活力，CCK-8法分析梯度浓度顺铂处理ccRCC细胞后IC50值，WB法检测糖酵解代谢途径相关蛋白的表达，Seahorse XP96法检测各处理组细胞的胞外酸化率（ECAR）和耗氧率（OCR），试剂盒检测细胞中丙酮酸、乳酸、ATP水平。双荧光素酶报告基因和染色质免疫共沉淀（ChIP）实验验证ABCC3与MYC间的结合关系，RNA结合蛋白免疫沉淀（RIP）实验验证LINC00462和MYC的结合关系。结果：数据库分析和qPCR实验结果显示，ABCC3在ccRCC组织和细胞中呈高表达，差异基因富集在糖酵解通路上。敲减或过表达ABCC3能够增加A-498细胞或降低786-O细胞对顺铂的敏感性，ABCC3可通过促进有氧糖酵解抑制A-498细胞对顺铂的敏感性，2-DG处理可以逆转过表达ABCC3对ccRCC细胞对顺铂敏感性的抑制作用。MYC可直接和ABCC3结合，LINC00462可招募转录因子MYC；敲低LINC00462可抑制ABCC3的表达，敲低LINC00462可抑制ccRCC细胞的有氧糖酵解，并提高其对顺铂敏感性；而进一步过表达ABCC3可逆转敲低LINC00462对ccRCC细胞有氧糖酵解的抑制作用和顺铂敏感性的提高。结论：LINC00462通过招募转录因子MYC激活ABCC3的表达促进ccRCC细胞的糖酵解，进而促进ccRCC细胞对顺铂敏感性。

Long non-coding RNA00461 regulates apoptosis in triple-negative breast cancer cells by combining with the proto-oncogene c-Myc / 中华内分泌外科杂志

Objective:To investigate the effect of long non-coding RNA00461 (LINC00461) on apoptosis of triple negative breast cancer cells.Methods:RT-qPCR was used to detect the expression of LINC00461 in normal breast epithelial cells MCF-10A, TNBC cell lines MDA-MB-231 and MDA-MB-468. The apoptosis rate was detected by Annexin V-FITC/PI double staining cell apoptosis kit. Western blot was used to detect apoptosis-associated protein. The localization of LINC00461 in cells was detected by FISH. RNA pulldown and RIP were used to detect the interaction between LINC00461 and c-Myc. The effect of LINC00461 on TNBC apoptosis was verified by subcutaneous tumorigenesis in nude mice.Results:Compared with MCF-10A, LINC00461 expression in MDA-MB-231 and MDA-MB-468 cells was significantly increased. Interference with LINC00461 significantly reduced the expression of LINC00461 and c-Myc protein. Overexpression of LINC00461 significantly decreased the expression level of apoptosis-related protein. Overexpression of LINC00461 significantly reduced the apoptosis rate by 50%-70%, with a statistically significant difference. FISH results showed that LINC00461 was mainly localized in the cytoplasm. RNA pulldown results showed that LINC00461 interacted with c-Myc. RIP results showed that the concentration of LINC00461 in c-Myc group was more than 400%, and the difference was statistically significant. In addition, overexpression of c-Myc reduced the promotion effect of knockdown LINC00461 on the apoptosis rate of 30%-50%. In animal experiments, overexpression of LINC00461 significantly increased tumor volume (50%-80%) and tumor weight (30%-50%) .Conclusion:LINC00461, mainly located in the cytoplasm, regulates the apoptosis of TNBC cells, and its molecular mechanism may be that LINC00461 interacts with c-Myc protein to play an important role in regulating the apoptosis of TNBC cells.

The reversal effect of albiflorin on multidrug resistance of human ovarian cancer and its mechanism / 中国药理学通报

Aim To study the reversal effect of albiflorin(AL)on multidrug resistance of human ovarian cancer and the potential mechanism. Methods The drug resistance reversal effect of AL on SKOV3/DDP cells was detected by CCK-8 kit,and the effect of AL on P-glycoprotein(P-gp)function was detected by flow cytometry. The effects of AL on MYC,WWP1 and ABCB1 in SKOV3/DDP cells were detected by RT-qPCR and Western blot. The MYC-knockdown SKOV3/DDP cell line was constructed by RNA interference technology,and its drug resistance,P-gp function and related gene and protein expression changes were investigated. Results AL had a drug resistance reversal effect on SKOV3/DDP cells and a concentration-dependent inhibitory effect on P-gp function. The inhibitory effects of AL 25,50 and 100 μmol·L-1 on ABCB1/P-gp,MYC and WWP1 were gradually enhanced. The inhibitory effect of MYCi975,a MYC inhibitor,on ABCB1/P-gp,MYC and WWP1 was stronger than or equivalent to that of AL 100 μmol·L-1 group. After knockdown of MYC in SKOV3/DDP cells,cell drug resistance,P-gp function,and related gene and protein expression were inhibited. Conclusions The drug resistance reversal effect of AL on SKOV3/DDP cells may be related to the inhibition of P-gp function and the expression of ABCB1/P-gp,MYC and WWP1,which provides an experiment base for the development of AL as a drug resistance reversal agent for the clinical treatment of ovarian cancer.

The differential effect of AICAR on c-Myc expression and proliferation in specific tumor cell lines / 中国药理学通报

Aim To investigate the effect of AICAR on the expression of the proto-oncogene c-Myc and cell proliferation rates in specific cancer cell lines. Methods The mRNA levels of c-Myc were evaluated using fluorescence-based qRT-PCR to examine the effect of AICAR treatment on c-Myc mRNA expression levels. Western blot was used to evaluate the protein levels of c-Myc following AICAR treatment. RNA interference was employed to determine whether the regulatory effect of AICAR on c-Myc was dependent on AMPK and the downstream metabolic enzymes relating to AICAR. Actinomycin D and cycloheximide were used to assess the effect of AICAR on the stability of cMyc mR-NA and protein. Western blot was used to examine the regulatory effect of AICAR on c-Myc in various cancer cell lines. The MTT assay was used to determine the effect of AICAR on cell viability in these cell lines. Results AICAR significantly up-regulated c-Myc at both mRNA and protein levels. The protein level of c-Myc reached a plateau 12 h after the AICAR treatment. The up-regulatory effect of c-Myc induced by AICAR was not dependent on either the AMPK signaling pathway or the downstream metabolites of AICAR. AICAR could significantly enhance the mRNA stability of c-Myc but did not affect the protein stability. The up-regulation of c-Myc induced by AICAR was cell-type specific. AICAR up-regulated c-Myc in SW1990, 786-0, and A549, while down-regulated c-Myc in HepG2, MCF7, and U20S. In HepG2 cells, AICAR treatment decreased cell viability. However, in SW1990 and A549 cells, AICAR treatment did not lead to any significant difference in cell viability. AICAR decreased the cell viability only when c-Myc was knocked down in SW1990 and A549 cells. Conclusions AICAR directly up-regulates c-Myc expression in an AMPK-independent manner. The up-regulation effect is cell-type dependent. The regulation of c-Myc expression by AICAR is linked to the inhibitory effect of AICAR on tumor cell proliferation.

Effects of Decitabine Combined with Anlotinib on Proliferation and Apoptosis of Multiple Myeloma Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the biological effects and its relative mechanism of decitabine combined with anlotinib on multiple myeloma cells.@*METHODS@#The human MM cell lines and primary cells were treated with different concentrations of decitabine, anlotinib, and decitabine+anlotinib, respectively. The cell viability was detected and combination effect was calculated by CCK-8 assay. The apoptosis rate was measured by flow cytometry and the level of c-Myc protein was determined by Western blot.@*RESULTS@#Both decitabine and anlotinib could effectively inhibit the proliferation and induce the apoptosis of MM cell lines NCI-H929 and RPMI-8226. The effect of combined treatment on the inhibition of cell proliferation and induction of apoptosis was stronger than that of single-drug treatment. The combination of the two drugs also showed strong cytotoxicity in primary MM cells. Decitabine and anlotinib could down-regulate the level of c-Myc protein in MM cells and the c-Myc level in the combination group was the lowest.@*CONCLUSION@#Decitabine combined with anlotinib can effectively inhibit the proliferation and induce apoptosis of MM cells, which provides a certain experimental basis for the treatment of human MM.

Advances in the study of the m6A methyltransferase METTL3 promoting bladder cancer progression via AFF4/NF-κB/MYC signaling network / 现代泌尿外科杂志

Bladder cancer (BCa) is one of the most common cancers in urology,whose pathogenesis is still unclear. Methyltransferase-like 3(METTL3) is the most important part of N6-methyladenosine methyltransferase complex (m6A MTC),which mediates the methylation of mRNA to regulate the stability and translation process of mRNA. Researches have shown that METTL3 can promote BCa development via AFF4/NF-κB/MYC signaling network,which involves many kinds of signaling molecules. In addition,METTL3 can affect the expressions of AFF4,NF-κB and MYC,so as to affect their downstream signaling pathways and finally promote the malignant progression of tumor.

Prokaryotic expression, polyclonal antibody preparation, spatio-temporal expression profile and functional analysis of c-Myc of Helicoverpa armigera (Lepidoptera: Noctuidae) / 生物工程学报

c-Myc protein encoded by c-Myc (cellular-myelocytomatosis viral oncogene) gene regulates the related gene expression through the Wnt/β-catenin signaling pathway, and has received extensive attention in recent years. The purpose of this study was to express Helicoverpa armigera c-Myc gene (Ha-c-Myc) by using prokaryotic expression system, prepare the polyclonal antibody, examine the spatio-temporal expression profile of Ha-c-Myc, and investigate the possible function of Ha-c-Myc in regulating H. armigera sterol carrier protein-2 (SCP-2) gene expression. The Ha-c-Myc gene was amplified by PCR and cloned into a prokaryotic expression plasmid pET-32a(+). The recombinant plasmid pET-32a-Ha-c-Myc was transformed into Escherichia coli BL21. IPTG was used to induce the expression of the recombinant protein. Protein was purified by Ni2+-NTA column and used to immunize New Zealand rabbits for preparing the polyclonal antibody. The Ha-c-Myc expression levels in different developmental stages (egg, larva, prepupa, pupa, and adult) of H. armigera and different tissues (midgut, fat body, head, and epidermis) of the prepupa were determined by real-time quantitative reverse transcription PCR (qRT-PCR). Ha-c-Myc siRNA was synthesized and transfected into H. armigera Ha cells. The relative mRNA levels of Ha-c-Myc and HaSCP-2 in Ha cells were detected by qRT-PCR. Results showed that the pET-32a-Ha-c-Myc recombinant plasmid was constructed. The soluble Ha-c-Myc protein of about 65 kDa was expressed in E. coli. The polyclonal antibody was prepared. Western blotting analysis suggested that the antibody had high specificity. Enzyme linked immunosorbent assay (ELISA) showed that the titer of the antibody was high. Ha-c-Myc gene expressed at all developmental stages, with high levels in the early and late instars of larva, and the prepupal stage. Tissue expression profiles revealed that Ha-c-Myc expressed in various tissues of prepupa, with high expression level in the midgut, but low levels in the epidermis and fat body. RNAi results showed that the knockdown of Ha-c-Myc expression significantly affected transcription of HaSCP-2, leading to a 50% reduction in HaSCP-2 mRNA expression level. In conclusion, the Ha-c-Myc was expressed through a prokaryotic expression system, and the polyclonal anti-Ha-c-Myc antibody was obtained. Ha-c-Myc may promote the expression of HaSCP-2 and play an important role in the lipid metabolism of H. armigera. These results may facilitate further study on the potential role and function mechanism of Ha-c-Myc in H. armigera and provide experimental data for exploring new targets of green pesticides.

INHBA-AS1 affects ornithine metabolism and EMT process of cervical cancer HeLa cells through c-Myc/SCD pathway / 中国肿瘤生物治疗杂志

@#[摘 要] 目的：探讨抑制素β亚基A反义RNA1（INHBA-AS1）对宫颈癌HeLa细胞EMT和鸟氨酸代谢途径的影响及其机制。方法：体外常规培养HeLa细胞，实验分为10组：对照组、阴性对照（NC）组、sh-INHBA-AS1组、PluriSIn 1[硬脂酰辅酶A去饱和酶（stearyl CoA desaturase，SCD）抑制剂]组、NC+PluriSIn 1组、sh-INHBA-AS1+PluriSIn 1组、10058-F4（c-Myc抑制剂）组、NC+10058-F4组、sh-INHBA-AS1+10058-F4组、sh-INHBA-AS1+OE-c-Myc组。平板克隆实验检测各组细胞的增殖能力，FCM检测各组细胞的凋亡情况，Transwell小室实验检测各组细胞的侵袭、迁移能力，qPCR法检测各组细胞中INHBA-AS1、c-Myc、SCD和EMT相关基因（N-cadherin、TGF-β、ZEB1）mRNA的表达，WB法检测各组细胞中c-Myc、SCD、EMT相关（N-cadherin、TGF-β、ZEB1）、S-腺苷-甲硫氨酸脱羧酶（SAMDC）和亚精胺/精胺N1-乙酰转移酶（SSAT）蛋白的表达，ELISA检测各组细胞上清液中鸟氨酸脱羧酶（ODC）的含量。结果：敲减INHBA-AS1表达使HeLa细胞的增殖、侵袭和迁移能力显著降低（均P<0.05）而细胞凋亡率显著升高（P<0.05），qPCR、WB法检测结果显示，敲减INHBA-AS1均可显著抑制HeLa细胞中c-Myc、SCD、N-cadherin、TGF-β、ZEB1和SAMDC的表达（均P<0.05），而促进SSAT的表达（P<0.05），并降低HeLa细胞上清液中ODC的含量（P<0.05）。与c-Myc抑制剂和SCD抑制剂单独处理相比，其联合敲减INHBA-AS1后上述作用更加显著（均P<0.05）；与sh-INHBA-AS1组相比，进一步过表达c-Myc后HeLa细胞的增殖能力显著升高（P<0.05）、SCD和N-cadherin蛋白表达水平显著升高（P<0.05）、细胞上清液中ODC含量显著升高（P<0.05）。结论：INHBA-AS1可通过c-Myc调控SCD的表达，从而影响HeLa细胞鸟氨酸代谢和EMT进程，进而促进HeLa细胞的增殖、侵袭和迁移能力。

Correlation between expression of Lin28B and C-myc in patients with laryngeal squamous cell carcinoma and clinicopathological features and prognosis / 中南大学学报(医学版)

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.

Study on the Biological Function of Abemecilib in Inhibiting the Proliferation, Invasion and Migration of Small Cell Lung Cancer with High c-Myc Expression / 中国肺癌杂志

BACKGROUND@#Small cell lung cancer (SCLC) with high c-Myc expression is prone to relapse and metastasis, leading to extremely low survival rate. Cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor Abemaciclib plays a key role in the treatment of tumors, but the effects and mechanisms on SCLC remain unclear. This study was to analyze the effect and molecular mechanism of Abemaciclib in inhibiting proliferation, migration and invasion of SCLC with high c-Myc expression, with a view to expanding a new direction for reducing the recurrence and metastasis.@*METHODS@#Proteins interacting with CDK4/6 were predicted using the STRING database. The expressions of CDK4/6 and c-Myc in 31 cases of SCLC cancer tissues and paired adjacent normal tissues were analyzed by immunohistochemistry. The effects of Abemaciclib on the proliferation, invasion and migration of SCLC were detected by CCK-8, colony formation assay, Transwell and migration assay. Western blot was used to detect the expressions of CDK4/6 and related transcription factors. Flow cytometry was used to analyze the effects of Abemaciclib on the cell cycle and checkpoint of SCLC.@*RESULTS@#The expression of CDK4/6 was associated with c-Myc by STRING protein interaction network. c-Myc can directly modalize achaete-scute complex homolog 1 (ASCL1), neuronal differentiation 1 (NEUROD1) and Yes-associated protein 1 (YAP1). Moreover, CDK4 and c-Myc regulate the expression of programmed cell death ligand 1 (PD-L1). Immunohistochemistry showed that the expressions of CDK4/6 and c-Myc in cancer tissues were higher than those in adjacent tissues(P<0.0001). CCK-8, colony formation assay, Transwell and migration assay verified that Abemaciclib could effectively inhibit the proliferation, invasion and migration of SBC-2 and H446OE(P<0.0001). Western blot analysis further showed that Abemaciclib not only inhibited CDK4 (P<0.05) and CDK6 (P<0.05), but also affected c-Myc (P<0.05), ASCL1 (P<0.05), NEUROD1 (P<0.05) and YAP1 (P<0.05), which are related to SCLC invasion and metastasis. Flow cytometry showed that Abemaciclib not only inhibited the cell cycle progression of SCLC cells (P<0.0001), but also significantly increased PD-L1 expression on SBC-2 (P<0.01) and H446OE (P<0.001).@*CONCLUSIONS@#Abemaciclib significantly inhibits the proliferation, invasion, migration and cell cycle progression of SCLC by inhibiting the expressions of CDK4/6, c-Myc, ASCL1, YAP1 and NEUROD1. Abemaciclib can also increase the expression of PD-L1 in SCLC.

Effects of MRE11 on Apoptosis and Proliferation of Esophageal Squamous Cancer Cells / 肿瘤防治研究

Objective To investigate the effect of MRE11 on the proliferation and apoptosis of esophageal squamous cancer cells and its molecular mechanism. Methods MRE11 expression was downregulated by MRE11 siRNA transfection in esophageal squamous cancer cells. The AKT agonist SC79 (0, 0.1, 0.5, 1, 1.5, 1.8, 2 μg/ml) were used to treat cells with MRE11 inhibition for 24 h. Overexpression vector pcDNA.3.1-c-myc was constructed and co-transfected cells with MRE11 siRNA. Western blot method was used to detect the protein expressions of MRE11, p-AKT and c-myc in esophageal squamous cancer cells Ec9706 and TE-1. The Annexin-V FITC/PI kit was used to detect the apoptosis of Ec9706 and TE-1 cells; the activity of caspase-3 was detected by the Caspase-3 activity detection kit; the proliferation of Ec9706 and TE-1 cells was tested by the BrdU method. Results The protein expressions of MRE11 in Ec9706 and TE-1 cells were significantly increased, compared with human esophageal epithelial Het-1A cells. After MRE11 siRNA transfection, AKT phosphorylation and the protein expressions of MRE11 and c-myc were significantly decreased in esophageal squamous cancer cells. MRE11 inhibition significantly promoted the apoptosis and caspase-3 activity in Ec9706 and TE-1 cells, while inhibited the proliferation of Ec9706 and TE-1 cells. SC79 (1.5, 1.8 and 2 μg/ml) significantly increased AKT phosphorylation in MRE11-suppressed esophageal squamous cancer cells, and reversed the inhibitory effects of MRE11 inhibition on c-myc protein expression and cell proliferation and the promoting effect on cell apoptosis. Overexpression of c-myc inhibited the inhibitory effect of MRE11 down-regulation on cell proliferation and the promotion on caspase-3 activity. Conclusion MRE11 inhibition could effectively inhibit the proliferation of esophageal squamous cancer cells and promote cell apoptosis by regulating AKT and c-myc.

Effects of N6-methyladenosine-induced LncRNA PVT1 targeting MYC on the stemness of ketamine-treated breast cancer cells / 中华内分泌外科杂志

Objective:To investigate the effect of ketamine on dryness maintenance of breast cancer (BC) cells by regulating LncRNA PVT1/MYC axis.Methods:BC cell line MCF-7 was treated with different concentration of ketamine (0, 5, 10 or 20 g/ml) or treated with 20g/ml ketamine for different periods (0, 24, 48 or 72h) . Furthermore, the expression of METTL3, PVT1 and MYC in MCF-7 cells was interfered and MCF-7 cells were divided into different groups.Western blot was used to detect the expression levels of stem cell characteristic related molecules (OCT4 and SOX2) . The expression level of PVT1/MYC in each group was detected by qRT-PCR. MeRIP analysis was used to detect THE m6A methylation level of PVT1.Results:Ketamine treatment significantly reduced the number of BC globules and inhibited the protein expression of OCT4 and SOX2 in a dose-and time-dependent manner (all P<0.05) . Ketamine regulated m6A level of METTL3-mediated PVT1. Compared with ketamine+pcDNA3.1 group (207±11) , the number of globules formed in ketamine+PVT1 group (311±15) was significantly increased ( t=12.06, P<0.001) , and the protein expression levels of OCT4 and SOX2 were increased ( t=9.68, P<0.001; t=11.50, P<0.001) . MYC was a downstream regulatory gene of PVT1. Compared with ketamine+PVT1+ Si-NC group, ketamine+PVT1+si-MYC group significantly reduced the number of spheroid formation ( t=0.54, P=0.005) and the expression levels of OCT4 and SOX2 proteins ( t=5.98, P=0.004) ( t=7.33, P=0.002) . Conclusion:Ketamine mediates the expression of PVT1 and its downstream gene MYC by inhibiting THE m6A level of PVT1, thus inhibiting the stem cell-like characteristics of BC cells.

Cancer Treatment Strategies by Targeting the Oncoprotein c-Myc / 中国生物化学与分子生物学报

c-Myc is a transcription factor involved in the Myc/Max/Mxd signal regulatory network. c-Myc plays important roles in human development and the oncogenesis or progression of different types of tumors. Current studies have shown that c-Myc mutations or expression changes are present in more than 70% of tumors. Therefore, c-Myc-targeted inhibitors might become a new strategy for tumor therapy. Currently, there is no clinical treatment for targeting c-Myc. With the continuous study aiming at the c-Myc targeted clinical application, Omomyc has become a representative c-Myc inhibitor by direct inhibition of c-Myc in tumors, which may be a feasible clinical treatment strategy. Although targeting c-Myc has broad prospects in cancer treatment, direct inhibition of c-Myc still has many risks and challenges. Therefore, in this review, firstly, we will summarize the regulatory network and biological functions of c-Myc in cells. Secondly, the potential significance of targeting c-Myc or its homologues in tumor therapy will be discussed. Additionally, the challenges faced by c-Myc as a potential therapeutic target in clinical application will be summarized. Finally, we will also discuss the advantages and disadvantages of some c-Myc inhibitors that have been discovered to date, such as small molecule inhibitors and protein and peptide inhibitors, therefore providing the theoretical basis for c-Myc targeted clinical therapy in cancer.

MYC and BCL-2 protein co-expression and prognosis of patients with diffuse large B-cell lymphoma: a propensity score matching analysis / 中华血液学杂志

Objective: We investigated the impact of MYC/BCL-2 protein co-expression on the prognosis of diffuse large B-cell lymphoma (DLBCL) patients and observed whether double expression (DE) remains an independent poor prognostic factor in DLBCL after the addition of therapeutic factors such as DA-EPOCH-R, central prophylaxis, and transplantation. Methods: Available pathological findings were retrospectively collected from 223 DLBCL patients at the Peking Union Medical College Hospital from 2015 to 2018. Seventy-five patients with high MYC/BCL-2 expression were categorized as the DE group. From the 148 non-DE patients, 75 DLBCL patients were selected as the control group, using a 1∶1 matching on propensity scores for age, international prognostic index score, treatment choice, and etc. The differences in overall survival (OS) and progression-free survival (PFS) between the two groups were compared. Results: The 3-year OS was (69.8±5.5) % for the DE group and (77.0±4.9) % for the non-DE group (P=0.225) , while the 3-year PFS was (60.7±5.8) % and (65.3±5.5) % , respectively (P=0.390) . Subgroup analysis in patients treated with the R-CHOP regimen revealed that for the DE and non-DE patients, the 3-year OS was (61.3±7.5) % and (77.2±5.6) % (P=0.027) , and the 3-year PFS was (52.1±7.5) % and (70.6±6.0) % (P=0.040) , respectively. Multivariate analysis showed that age, stage of Ann Arbor, COO staging, whether central prophylaxis was performed, and whether transplantation was performed were significant independent risk factors of the prognosis of DLBCL patients (P<0.05) . On the other hand, MYC/BCL-2 protein double expression was not significantly associated with prognostic outcomes. Conclusion: MYC/BCL-2 protein double expression was significantly associated with poor prognosis under R-CHOP regimen treatment, but the poor prognostic impact of DE on DLBCL was eliminated under intensive regimens such as DA-EPOCH-R and transplantation.

The development of small-molecule inhibitors targeting MYC / 药学学报

The MYC gene, one of the most common dysregulated driver genes in human cancers, is composed of three paralogous genes C-MYC, N-MYC and L-MYC. It is abnormally activated in more than half of cancer types. Since MYC plays an important role in the formation, maintenance and progression of cancer, targeting MYC is an effective strategy for cancer treatment. As a potential anti-cancer target, MYC is considered "undruggable" because it lacks a suitable pocket for accommodating small molecule inhibitors. Recently, under the guidance of protein structure information and many computational tools, many indirect strategies to inhibit MYC have emerged and shown favorable anti-cancer effects in tumor models. In this paper, the recent small molecules that indirectly target MYC are divided into inhibitors acting on the protein-protein interaction (PPI) among MYC and other proteins, and targeting inhibitors regulating MYC action. Additionally, the introduction and assessment towards compounds with different mechanisms are summarized to provide reference for the further research of MYC inhibitors.

c-MYC-mediated TRIB3/P62+ aggresomes accumulation triggers paraptosis upon the combination of everolimus and ginsenoside Rh2

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

Expression Level and Correlation of miR-211, miR-155, C-myc in Acute T Lymphocytic Leukemia / 中国实验血液学杂志

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.

Clinicopathological analysis and literature review of Burkitt-like lymphoma with 11q aberration / 中国综合临床

Objective:To investigate the clinicopathological features,differential diagnosis,treatment and prognosis of Burkitt-like lymphoma with 11q aberration (BLL-11q).Methods:The clinical manifestations,histological morphology,immunophenotype and molecular genetic changes of 2 cases of BLL-11q admitted to the department of pathology of The First People's Hospital of Lianyungang in 2020 and 2021 were analyzed retrospectively,and the relevant literatures were reviewed.Results:Patients were found with right neck masses inadvertently and grew rapidly. They presented with localized disease with Ann Arbor stages IA and IIA. Microscopically, the normal structure of the lymph node disappeared and was replaced by a diffuse proliferation of lymphocytes, with consistent morphology and medium size. And the presence of "star-sky" phenomenon was obvious, the morphological characteristics were similar to Burkitt lymphoma. Immunophenotypically, tumor cells were diffusely positive for CD20, CD79α, PAX5, CD10 and Bcl-6, partly moderately positive for C-MYC and MUM-1, however, CD3, Bcl-2, CD30 and TDT were negative,Ki-67 positive index was more than 95%, and EBER was negative. FISH detection showed that MYC, Bcl-2, and Bcl-6 were negative. Both cases had the 11q23.3 gain and 11q24.3 loss. Both patients were treated with chemotherapy and followed up for 10-22 months,and achieved complete remission and disease-free survival.Conclusion:BLL-11q is a rare germinal center B-cell lymphoma with abnormal long arm of chromosome 11 and lack of MYC gene rearrangement. It should be distinguished from Burkitt lymphoma, diffuse large B-cell lymphoma, B-lymphoblastic lymphoma, large B-cell lymphoma with IRF4 rearrangement and high-grade B-cell lymphoma. On the basis of morphology and immunophenotype, the diagnosis depends on genetic detection. There may be a better prognosis.