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Supplementary Figures and Tables show high expression of EF4 in cancer cells, when silence its expression induces apoptosis in various cancers.

Mitochondria regulate cellular bioenergetics and redox states and influence multiple signaling pathways required for tumorigenesis. In this study, we determined that the mitochondrial translation elongation factor 4 (EF4) is a critical component of tumor progression. EF4 was ubiquitous in human tissues with localization to the mitochondria (mtEF4) and performed quality control on respiratory chain biogenesis. Knockout of mtEF4 induced respiratory chain complex defects and apoptosis, while its overexpression stimulated cancer development. In multiple cancers, expression of mtEF4 was increased in patient tumor tissues. These findings reveal that mtEF4 expression may promote tumorigenesis via an imbalance in the regulation of mitochondrial activities and subsequent variation of cellular redox. Thus, dysregulated mitochondrial translation may play a vital role in the etiology and development of diverse human cancers.Significance: Dysregulated mitochondrial translation drives tumor development and progression. Cancer Res; 78(11); 2813–24. ©2018 AACR.

Xiaobo Nie,1 Huiyang Liu,1 Xiaoyun Wei,1 Lanqing Li,1 Linhua Lan,2 Lili Fan,1 Han Ma,1 Lei Liu,1 Yun Zhou,1 Ruifang Hou,1 Wei-Dong Chen1,3 1Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, School of Basic Medical Sciences, People’s Hospital of Hebi, Henan University, Kaifeng, People’s Republic of China; 2Key Laboratory of Diagnosis and Treatment of Severe Hepato-Pancreatic Diseases of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, People’s Republic of China; 3Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, Key Laboratory of Molecular Pathology, School of Basic Medical Science, Inner Mongolia Medical University, Hohhot, People’s Republic of ChinaCorrespondence: Wei-Dong Chen Email wdchenmed@163.comBackground: The dysregulation of microRNAs (miRNAs) and hepatotoxicity due to the aberrant accumulation of bile acids (BAs) are notorious causes that predispose an individual to the development of hepatocellular carcinoma (HCC). Farnesoid X receptor (FXR), encoded by NR1H4 gene, has been identified as a crucial BA receptor to maintain the homeostasis of BA pool and its expression is decreased in HCC. miR-382-5p plays an important role in the pathogenesis of many human malignancies and was reported to promote the proliferation and differentiation of normal liver cells and liver regeneration. However, there is still some controversy about its role in HCC microenvironment. This study aims to explore the expression pattern of miR-382-5p in HCC and its role in regulating FXR during the development of HCC.Methods: Tissues collected from 30 HCC patients were subjected to extraction of total RNA and quantitative real-time PCR (qRT-PCR) for the analyses of miR-382-5p expression and NR1H4 mRNA levels, and their expressions were verified by analyzing the online HCC-related GSE datasets. The role of miR-382-5p in regulating cellular proliferation and expression of FXR in different HCC cell lines was analyzed by qRT-PCR, Western Blot, real-time cellular analysis (RTCA) and luciferase reporter assays. The role of miR-382-5p in regulating downstream genes of FXR in HCC cells was also analyzed.Results: miR-382-5p was upregulated in HCC tissues and inversely associated with the downregulation of NR1H4 mRNA levels. The luciferase reporter assay proved that miR-382-5p directly targeted the 3ʹ-untranslated region (3ʹ-UTR) of human NR1H4 mRNA. Overexpression of miR-382-5p led to a malignant proliferation of HCC cells by suppressing the expression of FXR. In contrast, blocking the endogenous miR-382-5p was sufficient to suppress the cellular proliferation rate of HCC through increasing FXR expression. Additionally, miR-382-5p inhibited the expression of some target genes of FXR, including SHP, FGF19 and SLC51A, and this inhibitory effect was FXR-dependent.Conclusion: Therefore, miR-382-5p promotes the progression of HCC in vitro by suppressing FXR and could serve as a valuable therapeutic target for HCC treatment.Keywords: hepatocellular carcinoma, miRNA-382-5p, FXR, proliferation

To investigate the potential antitumor activity of synthetic triterpenoid, methyl-2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oate (CDDO-Me) in pancreatic ductal adenocarcinoma (PDAC), MTT cytotoxicity assay, and xenograft nude mice assay were performed to evaluate tumor growth in vitro and in vivo. Seahorse XFe96 bioenergetics analyzer was applied to determine aerobic glycolysis and mitochondrial respiration. Western blot and quantitative reverse transcription-polymerase chain reactions are used to detect protein and messenger RNA transcripts of SLC1A5 and metabolic enzymes. We confirmed the strong antitumor activity of CDDO-Me in suppressing PDAC growth. Mechanistically, we demonstrated CDDO-Me induced mitochondrial respiration and aerobic glycolysis dysfunction. We also verified CDDO-Me downregulated glutamine transporter SLC1A5, resulting in excessive reactive oxygen species (ROS) levels that suppressed tumor growth. Moreover, we confirmed that SLC1A5 depletion reduced the ratio of glutathione/oxidized glutathione. We also found CDDO-Me could inhibit N-linked glycosylation of SLC1A5, which promotes protease-mediated degradation. Finally, we confirmed SLC1A5 was significantly overexpressed in PDAC and closely correlated with the poor prognosis of PDAC patients. Our work uncovers CDDO-Me is effective at suppressing PDAC cell growth in vitro and in vivo and illuminates CDDO-Me caused excessive ROS and cellular bioenergetics disruption which contributed to CDDO-Me inhibited PDAC growth. Our data highlights CDDO-Me could be considered a potential compound for PDAC therapy, and SLC1A5 could be a novel biomarker for PDAC patients.

The S100 protein family genes play a crucial role in multiple stages of tumorigenesis and progression. Most of S100 genes are located at chromosome locus 1q21, which is a region frequently rearranged in cancers. Here, we examined the expression of the S100 family genes in paired pancreatic ductal adenocarcinoma (PDAC) samples and further validated the expression of S100A16 by immunohistochemistry staining. We found that S100A16 is significantly upregulated in clinical PDAC samples. However, its roles in PDAC are still unclear. We next demonstrated that S100A16 promotes PDAC cell proliferation, migration, invasion, and metastasis both in vitro and in vivo. Knockdown of S100A16 induces PDAC cell cycle arrest in the G2/M phase and apoptosis. Furthermore, we also demonstrated that S100A16 promotes PDAC cell proliferation, migration, and invasion via AKT and ERK1/2 signaling in a fibroblast growth factor 19 (FGF19)-dependent manner. Taken together, our results reveal that S100A16 is overexpressed in PDAC and promotes PDAC progression through FGF19-mediated AKT and ERK1/2 signaling, suggesting that S100A16 may be a promising therapeutic target for PDAC. S100A16 was upregulated in PDAC and associated with prognosis of PDAC patients. S100A16 regulates apoptosis and the cell cycle of pancreatic cancer cells. S100A16 promotes the progression of pancreatic cancer by AKT-ERK1/2 signaling. S100A16 may be a promising therapeutic target for PDAC.

Pancreatic ductal adenocarcinoma (PDAC) is severe malignant tumor in human, the outcomes of PDAC is extremely poor. Here, we evaluated the potential anti-tumor activity of chlorogenic Acid (CA) in PDAC. Here, we found CA was effective to suppress PDAC cell growth in vitro and in vivo. Importantly, we found overall oxygen consumption rate was significantly decreased in CA dose-dependent manner. We also found glycolysis reverse was decreased in CA-treated cells, while basal glycolysis and glycolytic capacity were not significantly changed. Mechanistically, we demonstrated TFR1 could be a novel downstream target of CA, which is essential for PDAC cell growth and cellular bioenergetics maintenance. Furthermore, we validated that CA-reduced c-Myc resulted to down-regulation of TFR1, which contributes to mitochondrial respiration dysfunction and cell growth delay. Together, this study indicates that CA suppresses PDAC cell growth through targeting c-Myc-TFR1 axis and suggests CA could be considered as a promising compound for PDAC treatment.

Human Cytomegalovirus (HCMV) infection of monocytes results in the production of inflammatory cytokine interleukin-1β (IL-1β). The objective of the study was to explore the mechanism behind the activation of inflammation. HCMV infection activated the NLRP3 inflammasome and enhanced the secretion of IL-1β in THP-1 cells. Besides, HCMV infection caused mitochondrial dysfunction, including excessive ROS production, decreased mitochondrial membrane potential, and increased mitochondrial fusion. Importantly, the infection reduced the expression of TFAM protein and the release of mitochondrial DNA into the cytoplasm, which may contribute to the activation of NLRP3 inflammasome. Collectively, our finding suggests that HCMV infection may activate NLRP3 inflammasome by releasing mtDNA into the cytosol in human THP-1 cells and provides novel insights into the innate immune response against HCMV infection.

24-epibrassinolide (EBR) is a ubiquitous steroidal phytohormone with anticancer activity. Yet the cytotoxic effects and mechanism of EBR on hepatocarcinoma (HCC) cells remain elusive.Cell counting kit-8 (CCK-8) assay was performed to evaluate cell viability. Real-time cell analysis (RTCA) technology and colony formation assays were used to evaluate cell proliferation. The apoptosis ratio was measured by flow cytometry. Seahorse XFe96 was applied to detect the effects of EBR on cellular bioenergetics. RNA-seq analysis was performed to investigate differences in gene expression profiles. Western blot and qRT-PCR were used to detect the changes in target molecules.EBR induced apoptosis and caused energy restriction in HCC, both of which were related to insulin-like growth factor-binding protein 1 (IGFBP1). EBR rapidly and massively induced IGBFP1, part of which was transcribed by activating transcription factor-4 (ATF4). The accumulation of secreted and cellular IGFBP1 had different important roles, in which secreted IGFBP1 affected cell energy metabolism by inhibiting the phosphorylation of Akt, while intracellular IGFBP1 acted as a pro-survival factor to resist apoptosis. Interestingly, the extracellular signal-regulated kinase (ERK) inhibitor SCH772984 and MAP/ERK kinase (MEK) inhibitor PD98059 not only attenuated the EBR-induced IGFBP1 expression but also the basal expression of IGFBP1. Thus, the treatment of cells with these inhibitors further enhances the cytotoxicity of EBR.Taken together, these findings suggested that EBR can be considered as a potential therapeutic compound for HCC due to its pro-apoptosis, restriction of energy metabolism, and other anti-cancer properties. Meanwhile, the high expression of IGFBP1 induced by EBR in HCC contributes to our understanding of the role of IGFBP1 in drug resistance.

Protein quality control is pivotal to cellular homeostasis and integrity of cardiomyocytes for maintenance of normal heart function. The unfolded protein response (UPR) is an adaptive process to modulate protein quality control in the endoplasmic reticulum (ER) and mitochondria, and is accordingly termed UPRER and UPRmt, respectively. Lon protease (LonP1) is a highly conserved mitochondrial protease to modulate UPRmt, which is involved in regulating metabolism, mitophagy, and stress response. However, whether LonP1 regulates UPRER remains elusive. To investigate the regulation of protein quality control in cardiomyocytes, we generated cardiac-specific LonP1 deletion mice. Our findings show that LonP1 deficiency caused impaired mitochondrial respiratory function and fragmentation. Surprisingly, both UPRER and UPRmt is substantially induced in LonP1-deletion heart suggesting of LonP1 as a novel regulator of UPRER; however, the activation of UPRER occurs earlier than UPRmt in response to LonP1 deletion. Consequently, cardiac-specific LonP1 deficiency causes aberrant metabolic reprogramming of cardiomyocytes, pathological heart remodeling, as well as impeded heart function. We uncovered the novel function of LonP1 as an UPRmt mediator, and reciprocal orchestration of UPRmt and UPRER and mitochondrial dynamics regulated by LonP1 in the cardiomyocytes that is critical to maintain heart function, which offers exciting new insights into the potential therapeutic strategy for heart failure.

Available evidence suggests that human cytomegalovirus (HCMV) infection may be implicated in the progression of colorectal cancer (CRC). However, the correlation between HCMV infection and survival outcomes in CRC patients is unclear. Here, we constructed a flow algorithm to identify HCMV sequences based on the RNA-seq data of CRC patients derived from Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The patients' clinical information matrix was used to calculate Euclidean distance to filter out suitable patients not infected with HCMV, combining with the patient's survival outcome to reveal how HCMV infection is involved in CRC progression.HCMV infection is widespread in CRC patients., The prevalence of HCMV infection is ranging from 10% to 36% in 4 independent CRC datasets with infection being concentrated in carcinoma tissue rather than in normal tissue. In addition, HCMV positive patients had a poor survival prognosis, with three of the HCMV genes associated with poor patient survival outcomes, UL82, UL42 and UL117. Most importantly, we suppose that the regulation of immune function by HCMV may be the key to the poor prognosis of CRC patients. We found that HCMV infection was associated with poor prognosis in CRC patients and identified three prognosis associated HCMV genes. The regulation of immune function caused by HCMV infection was the key factor while HCMV positive CRC patients mostly presented a state of immunosuppression. This may provide new ideas for personalized treatment of CRC patients, especially in immunotherapy.

Evidence suggests that human cytomegalovirus (HCMV) infection may be implicated in the progression of colorectal cancer (CRC). However, the correlation between HCMV infection and survival outcomes in patients with CRC remains unclear. Here, we constructed a flow algorithm to identify HCMV sequences based on the RNA-seq data of patients with CRC derived from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The patients' clinical information matrix was used to calculate the Euclidean distance to filter out suitable patients not infected with HCMV, combined with patients' survival outcomes, to reveal how HCMV infection is involved in CRC progression. HCMV infection is widespread in patients with CRC, and the prevalence of HCMV infection ranges from 10 to 36% in four independent CRC datasets, with infection being concentrated in carcinoma tissue rather than in normal tissue. In addition, HCMV-positive patients had a poor survival prognosis, with three HCMV genes, UL82, UL42, and UL117, associated with poor patient survival outcomes. Most importantly, we suppose that the regulation of immune function by HCMV may be key to the poor prognosis of patients with CRC. We found that HCMV infection was associated with poor prognosis in CRC patients and identified three prognosis-associated HCMV genes. The regulation of immune function caused by HCMV infection was the key factor, while HCMV-positive patients with CRC mostly presented with a state of immunosuppression. This may provide new ideas for the personalized treatment of patients with CRC, especially with respect to immunotherapy.

Cannabidiol (CBD), a phytochemical derived from Cannabis sativa L., has been demonstrated to exhibit promising anti-tumor properties in multiple cancer types. However, the effects of CBD on hepatocellular carcinoma (HCC) cells remain unknown. We have shown that CBD effectively suppresses HCC cell growth in vivo and in vitro, and induced HCC cell pyroptosis in a caspase-3/GSDME-dependent manner. We further demonstrated that accumulation of integrative stress response (ISR) and mitochondrial stress may contribute to the initiation of pyroptotic signaling by CBD. Simultaneously, CBD can repress aerobic glycolysis through modulation of the ATF4–IGFBP1–Akt axis, due to the depletion of ATP and crucial intermediate metabolites. Collectively, these observations indicate that CBD could be considered as a potential compound for HCC therapy.

Many extracts and purified alkaloids of M. cordata (Papaveraceae family) have been reported to display promising anti-tumor effects by inhibiting cancer cell growth and inducing apoptosis in many cancer types. However, no evidence currently exists for anti-pancreatic cancer activity of alkaloids extracted from M. cordata, including a novel alkaloid named 6‑methoxy dihydrosphingosine (6-Methoxydihydroavicine, 6-ME) derived from M. cordata fruits.The aim of this study was to investigate the anti-tumor effects of 6-ME on PC cells and the underlying mechanism.CCK-8, RTCA, and colony-formation assays were used to analyze PC cell growth. Cell death ratios, changes in MMP and ROS levels were measured by flow cytometry within corresponding detection kits. A Seahorse XFe96 was employed to examine the effects of 6-ME on cellular bioenergetics. Western blot and q-RT-PCR were conducted to detect changes in target molecules.6-ME effectively reduced the growth of PC cells and promoted PCD by activating RIPK1, caspases, and GSDME. Specifically, 6-ME treatment caused a disruption of OAA metabolism and increased ROS production, thereby affecting mitochondrial homeostasis and reducing aerobic glycolysis. These responses resulted in mitophagy and RIPK1-mediated cell death.6-ME exhibited specific anti-tumor effects through interrupting OAA metabolic homeostasis to trigger ROS/RIPK1-dependent cell death and mitochondrial dysfunction, suggesting that 6-ME could be considered as a highly promising compound for PC intervention.

Pancreatic carcinoma (PC) is a severe disease associated with high mortality. Although strategies for cancer therapy have made great progress, outcomes of pancreatic carcinoma patients remain extremely poor. Therefore, it is urgent to find novel biomarkers and therapeutic targets. To identify biomarkers for early diagnosis and therapy, three mRNA microarray datasets and two miRNA datasets were selected, and combinative analysis was performed by GEO2R. Functional and pathway enrichment analysis were performed using DAVID database. MiRTarBase, miRWalk and Diana Tools were used to get key genes. TCGA, HPA and western blotting were used to verify diagnostic and prognostic value of key genes. By integrating mRNA and miRNA expression profiles, we identified 114 differentially expressed genes and 114 differentially expressed miRNAs, respectively. Then, three overlapping key genes, RUNX2, LAMC2 and FBXO32, were found. Their protein levels in pancreatic tissue from PC patients and normal people were analyzed by immunohistochemical staining and western blotting. RUNX2 showed a potential property to identify PC. Aberrant over-expression of LAMC2 was associated with poor prognosis of PC patients, tumor status and subtypes. In summary, our current study identified that RUNX2 and LAMC2 may be promising targets for early diagnosis and therapy of PC patients.

Background: Pancreatic carcinoma (PC) is a severe disease associated with high mortality. Although strategies for cancer therapy made great progress, outcomes of pancreatic ductal adenocarcinoma patients remain extremely poor. Therefore, it is urgent to find novel biomarkers and therapeutic targets to improve outcomes of patients. Methods: To identify general applicable targets for early diagnosis and therapy, we selected related microarray data which including three mRNA microarray datasets GSE62165, GSE15471, GSE32676 and two miRNA datasets GSE24279, GSE32678, and combinative analysis was performed by GEO2R. Functional and pathway enrichment analysis were performed using the DAVID database. MiRTarBase, miRWalk, Diana Tools and TBtools were used to get keys. TCGA database, HPA database and western blot experiments were used to verify diagnostic and prognostic value of key genes.Results: By integrating mRNA and miRNA expression profiles, we identified 114 differentially expressed genes (DEGs) and 114 differentially expressed miRNAs (DEMs), respectively. Furthermore, three overlapping key genes, RUNX2, LAMC2 and FBXO32, were found by compared with DEMs target genes and DEGs. In detail, deregulation of 8 key miRNAs were closely related to poor outcomes and participated in crucial genes regulation which may contribute to build a miRNA biomarker panel for prognosis. Moreover, we confirmed that RUNX2 showed a potential property for distinguishing PC and normal people. We also demonstrated that aberrant over-expression of LAMC2 was associated with poor prognosis of PC patients as well as human tumor status and subtypes. The protein levels of RUNX2 and LAMC2 in PC patients were further verified by IHC from Human Protein Atlas and western blot experiments. Conclusions: In summary, our current study identified that RUNX2 and LAMC2 may be promising targets for early diagnosis and therapy of PC patients.

The S100 protein family genes play a crucial role in multiple stages of tumorigenesis and progression. Most of S100 genes are located at chromosome locus 1q21, which is a region frequently rearranged in cancers. Here, we examined the expression of the S100 family genes in paired pancreatic ductal adenocarcinoma (PDAC) samples and further validated the expression of S100A16 by immunohistochemistry staining. We found that S100A16 is significantly upregulated in clinical PDAC samples. However, its roles in PDAC are still unclear. We next demonstrated that S100A16 promotes PDAC cell proliferation, migration, invasion, and metastasis both in vitro and in vivo. Knockdown of S100A16 induces PDAC cell cycle arrest in the G2/M phase and apoptosis. Furthermore, we also demonstrated that S100A16 promotes PDAC cell proliferation, migration, and invasion via AKT and ERK1/2 signaling in a fibroblast growth factor 19 (FGF19)-dependent manner. Taken together, our results reveal that S100A16 is overexpressed in PDAC and promotes PDAC progression through FGF19-mediated AKT and ERK1/2 signaling, suggesting that S100A16 may be a promising therapeutic target for PDAC. S100A16 was upregulated in PDAC and associated with prognosis of PDAC patients. S100A16 regulates apoptosis and the cell cycle of pancreatic cancer cells. S100A16 promotes the progression of pancreatic cancer by AKT-ERK1/2 signaling. S100A16 may be a promising therapeutic target for PDAC.

Pancreatic cancer (PC) is the most severe and serious deadliest cancer type worldwide. Centromeric proteins (CENPs) family are involved in centromere formation and kinetochore organization during mitosis and play an important role in cancers. Here, we analyzed all CENPs in a panel of PC tissues and non-tumor tissues by genomics profile. We identified that CENPF is significantly upregulated in PC and correlated with poor prognosis of patients. Furthermore, silencing CENPF significantly inhibited PC cell proliferation, migration and epithelial-mesenchymal transition (EMT), and caused cell cycle arrest at the G2/M phase, meanwhile, in vivo growth of pancreatic cells. Moreover, the TNF pathway and longevity regulating pathways are two potential pathways, which were regulated by CENPF. These findings investigated the clinical and functional contribution of CENPF as a novel biomarker for PC.

SIRT6 belongs to class III sirtuin family with NAD+-dependent histone deacetylase activities and controls multiple processes including aging, metabolism and inflammation. In recent years, increasing studies showed tumor suppressor role of SIRT6 in HCC development. We established a two-stage DEN followed CCl4 induced liver carcinogenesis in the hepatic-specific SIRT6 HKO mice models and found that hepatic SIRT6 deficit significantly promotes liver injury and liver cancer through inhibition of the ERK1/2 pathway. SIRT6 was compensatory upregulated in mice tumor tissues and human HCC cells and overexpressed SIRT6 inhibits tumor growth both in vitro and in vivo. Taken together, we provide a useful mouse model for delineating the molecular pathways involved in chronic liver diseases and primary liver cancer and suggest that SIRT6 can be a promising target for HCC therapies.

Deferoxamine (DFO) was found to modulate multiple cellular pathways involved in the growth of breast cancer, hepatocellular carcinoma, lung cancer and bladder cancer. However, the effect of DFO on esophageal squamous cell carcinoma (ESCC) remains unclear. Here, we report that DFO-treated ESCC cells show strong anti-tumorigenic properties, such as inhibition of cell proliferation, induction of cell cycle arrest, and promotion of apoptosis. Mechanistically, DFO significantly activated ERK1/2 signaling, which is reactive oxygen species (ROS)-dependent. ERK1/2 activation suppressed mitochondrial respiration and aerobic glycolysis in ESCC cells, resulting in reduced production of ATP and key precursor metabolites. Cell proliferation was functionally rescued by the ROS scavenger N-acetyl-l-cysteine (NAC) and the ERK1/2 inhibitor SCH7 72984. Additionally, our data showed that activated ERK1/2 was partially translocated to the mitochondria, which indicated that DFO-activated ERK1/2 may suppress tumor formation through inhibition of mitochondrial respiration. Moreover, the decreased c-Myc expression caused by DFO resulted in the inhibition of cell migration. Taken together, our study demonstrate that DFO activates ERK1/2 and downregulates c-Myc to perturb mitochondrial homeostasis and promote apoptosis, resulting in the novel anti-neoplastic activity of DFO in ESCC.

Mitochondrial transcription factor A (TFAM) is essential for the replication, transcription and maintenance of mitochondrial DNA (mtDNA). The role of TFAM in non-small cell lung cancer (NSCLC) remains largely unknown. Herein, we report that downregulation of TFAM in NSCLC cells resulted in cell cycle arrest at G1 phase and significantly blocked NSCLC cell growth and migration through the activation of reactive oxygen species (ROS)-induced c-Jun amino-terminal kinase(JNK)/p38 MAPK signaling and decreased cellular bioenergetics. We further found that TFAM downregulation in NSCLC cells led to increased apoptotic cell death and enhanced the sensitivity of NSCLC cells to cisplatin. Tissue microarray (TMA) data showed that elevated expression of TFAM was related to the histological grade and TNM stage of NSCLC patients. We also demonstrated that TFAM is an independent prognostic factor for overall survival of NSCLC patients. Taken together, our findings suggest that TFAM could serve as a potential diagnostic biomarker and molecular target for the treatment of NSCLC, as well as for prediction of the effectiveness of chemotherapy.

The aim of the present study was to explore the effects of oxidative stress induced by CoCl2 and H2O2 on the regulation of bioenergetics of esophageal squamous cell carcinoma (ESCC) cell line TE-1 and analyze its underlying mechanism. Western blot results showed that CoCl2 and H2O2 treatment of TE-1 cells led to significant reduction in mitochondrial respiratory chain complex subunits expression and increasing intracellular reactive oxygen species (ROS) production. We further found that TE-1 cells treated with CoCl2, a hypoxia-mimicking reagent, dramatically reduced the oxygen consumption rate (OCR) and increased the extracellular acidification rate (ECAR). However, H2O2 treatment decreased both the mitochondrial respiration and aerobic glycolysis significantly. Moreover, we found that H2O2 induces apoptosis in TE-1 cells through the activation of PARP, Caspase 3, and Caspase 9. Therefore, our findings indicate that CoCl2 and H2O2 could cause mitochondrial dysfunction by up-regulation of ROS and regulating the cellular bioenergy metabolism, thus affecting the survival of tumor cells.

Non-small cell lung cancer (NSCLC) accounts for approximately 80-85% of all lung cancer cases. Cigarette smoking is the number one risk factor which is attributed to more than four out of five cases of lung cancers. The prognostic impact of cell cycle regulation-associated tumor suppressors including p53 and p21 for NSCLC is still controversial. In the present study, we examined p53 and p21 expression using immunoblotting in tumor and adjacent non-cancerous tissues from NSCLC patients. Moreover, tissue microarrays (TMAs) including 150 specimens was used to examine p53 and p21 expression by immunohistochemical staining (IHC). The association between p53/p21 and various clinicopathological characteristics was evaluated. Kaplan-Meier overall survival was used to analyze the association between p53/p21 expression and prognosis of NSCLC patients, as well as the association of cigarette smoking with p53/p21 expression and prognosis. The results of the immunoblotting showed that expression of p53 and p21 in tumor tissues was significantly higher than that in the matched adjacent non-cancerous tissues (P

Mitochondria regulate cellular bioenergetics and redox states and influence multiple signaling pathways required for tumorigenesis. In this study, we determined that the mitochondrial translation elongation factor 4 (EF4) is a critical component of tumor progression. EF4 was ubiquitous in human tissues with localization to the mitochondria (mtEF4) and performed quality control on respiratory chain biogenesis. Knockout of mtEF4 induced respiratory chain complex defects and apoptosis, while its overexpression stimulated cancer development. In multiple cancers, expression of mtEF4 was increased in patient tumor tissues. These findings reveal that mtEF4 expression may promote tumorigenesis via an imbalance in the regulation of mitochondrial activities and subsequent variation of cellular redox. Thus, dysregulated mitochondrial translation may play a vital role in the etiology and development of diverse human cancers. Significance: Dysregulated mitochondrial translation drives tumor development and progression. Cancer Res; 78(11); 2813–24. ©2018 AACR.

The natural small molecule compound: 2,3,5,6-tetramethylpyrazine (TMP), is a major component of the Chinese medicine Chuanxiong, which has wide clinical applications in dilating blood vessels, inhibiting platelet aggregation and treating thrombosis. Recent work suggests that TMP is also an antitumour agent. Despite its chemotherapeutic potential, the mechanism(s) underlying TMP action are unknown. Herein, we demonstrate that TMP binds to mitochondrial transcription factor A (TFAM) and blocks its degradation by the mitochondrial Lon protease. TFAM is a key regulator of mtDNA replication, transcription and transmission. Our previous work showed that when TFAM is not bound to DNA, it is rapidly degraded by the ATP-dependent Lon protease, which is essential for mitochondrial proteostasis. In cultured cells, TMP specifically blocks Lon-mediated degradation of TFAM, leading to TFAM accumulation and subsequent up-regulation of mtDNA content in cells with substantially low levels of mtDNA. In vitro protease assays show that TMP does not directly inhibit mitochondrial Lon, rather interacts with TFAM and blocks degradation. Pull-down assays show that biotinylated TMP interacts with TFAM. These findings suggest a novel mechanism whereby TMP stabilizes TFAM and confers resistance to Lon-mediated degradation, thereby promoting mtDNA up-regulation in cells with low mtDNA content.

Paclitaxel induces apoptosis in a variety of cancer cells. However, the mechanism of paclitaxel inducing apoptosis in human esophageal squamous cell carcinoma (ESCC) remains to be defined. In this study, we found that paclitaxel-induced apoptosis by increasing the relevant apoptosis protein expression and the release of cytochrome c via downregulation of signal transducer and activator of transcription 3 (STAT3) and phospho-STAT3 (Ser727). In addition, paclitaxel treatment of ESCC cells EC-1 and Eca-109 led to marked mitochondrial membrane potential depolarization and significantly increasing of reactive oxygen species. Moreover, paclitaxel treatment resulted in the inhibition of mitochondrial respiration. In conclusion, our findings reveal that paclitaxel induced apoptosis in both EC-1 and Eca-109 cells through the reduction of STAT3 and phospho‑STAT3 (Ser727) level, and suggest that paclitaxel may be of therapeutic potential in the treatment of ESCC through the induction of mitochondrial apoptosis in ESCC cells.

A high order multiplication perturbation method for linear time-varying dynamic system is presented. Firstly the time domain is dispersed with small time interval and the coefficient matrix of the dynamic system is decomposed into a “large amount” and a “small amount” in each time interval. One order perturbation system is then presented from the original dynamic system by a variable transformation which is also a linear time-varying dynamic system. The coefficient matrix of the new system is also decomposed into a “large amount” and a “small amount” and then higher order perturbation system can be obtained by another variable transformation. The final perturbation system can be solved exactly after abandoning the “small amount” of the coefficient matrix in the final system, and then the answer to the original problem can be determined through a series of inverse transform. Since the transfer matrix is the product of a series of exponential matrix which can be calculated accurately by the precise time integration method, so the proposed method has fine accuracy, efficiency and stability. The proposed method actually is a high order symplectic conservative perturbation method for the Hamiltonian system. The examples show that the proposed method can also give good results even though a large time step selected, and with the increase of the perturbation number, the perturbation solutions can tend to exact solutions rapidly.

ATP-dependent Lon protease within mitochondrial matrix contributes to the degradation of abnormal proteins. The oxidative or hypoxic stress which represents the stress phenotype of cancer leads to up-regulation of Lon. However, the role of Lon in bladder cancer remains undefined. Here, we found that Lon expression in bladder cancer tissues was significantly higher than those in noncancerous tissues; down-regulation of Lon in bladder cancer cells significantly blocked cancer cell proliferation via suppression c-Jun N-terminal kinase (JNK) phosphorylation due to decreased reactive oxygen species (ROS) production and enhanced the sensitivity of bladder cancer cells to chemotherapeutic agents by promoting apoptosis. We further found that Lon down-regulation in bladder cancer cells decreased cellular bioenergetics as determined by measuring aerobic respiration and glycolysis using extracellular flux analyzer. The tissue microarray (TMA) results showed that high expression of Lon was related to the T and TNM stage, as well as histological grade of bladder cancer patients. We also demonstrated that Lon was an independent prognostic factor for overall survival of bladder cancer. Taken together, our data suggest that Lon could serve as a potential diagnostic biomarker and therapeutic target for treatment of bladder cancer, as well as for prediction of the effectiveness of chemotherapy.

Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype of esophageal cancer and one of the most aggressive types of malignancy, with a high rate of mortality. Early diagnosis and treatment may improve the prognosis of ESCC and, thus, survival rates. As a significant tumor suppressor, p53 is closely associated with apoptosis and the differentiation of cancer cells. The present study evaluated the expression levels of the p53 protein and the clinical significance in patients presenting with ESCC. The p53 protein expression level of 64 paired ESCC and tumor-adjacent normal tissues was evaluated using western blot analysis. In addition, immunohistochemistry (IHC) was performed to detect the p53 expression level in specimens from 118 paraffin-embedded cancerous tissues. The correlation of the p53 expression level with the clinicopathological parameters and prognosis of the ESCC patients was also analyzed. The p53 protein was identified to be highly expressed in the ESCC tissue, with western blot analysis demonstrating that the expression level of p53 in the cancerous tissue was 1.89 times that of the tumor-adjacent normal tissue (P

The human mitochondrial ATP-dependent Lon protease functions in regulating the metabolism and quality control of proteins and mitochondrial DNA (mtDNA). However, the role of Lon in cancer is not well understood. Therefore, this study was undertaken to investigate the importance of Lon in cervical cancer cells from patients and in established cell lines. Microarray analysis from 30 cancer and 10 normal cervical tissues were analyzed by immunohistochemistry for Lon protein levels. The expression of Lon was also examined by immunoblotting 16 fresh cervical cancer tissues and their respective non-tumor cervical tissues. In all cases, Lon expression was significantly elevated in cervical carcinomas as compared to normal tissues. Augmented Lon expression in tissue microarrays did not vary between age, tumor-node-metastasis grades, or lymph node metastasis. Knocking down Lon in HeLa cervical cancer cells by lentivrial transduction resulted in a substantial decrease in both mRNA and protein levels. Such down-regulation of Lon expression significantly blocked HeLa cell proliferation. In addition, knocking down Lon resulted in decreased cellular bioenergetics as determined by measuring aerobic respiration and glycolysis using the Seahorse XF24 extracellular flux analyzer. Together, these data demonstrate that Lon plays a potential role in the oncogenesis of cervical cancer, and may be a useful biomarker and target in the treatment of cervical cancer. Lon; immunohistochemistry; cervical cancer; cell proliferation; cellular bioenergetics.