Inhibitors of apoptosis proteins (IAPs) expression and their prognostic significance in hepatocellular carcinoma

Synergistic effects of Smac mimetic APG-1387 with anti-PD-1 antibody are attributed to increased CD3 + NK1.1 + cell recruitment secondary to induction of cytokines from tumor cells

BACKGROUND

Immune checkpoint inhibitors are approved for the treatment of various tumors, but the response rate is not satisfactory in certain malignancies. Inhibitor of apoptosis proteins (IAP) ubiquitin-E3 ligase activity is involved in the regulation of immune responses. APG-1387 is a novel second mitochondria-derived activator of caspase (Smac) mimetic IAP inhibitor. The aim of this study was to explore the synergistic effect of APG-1387 when combined with anti-PD-1 antibody in a preclinical setting.

METHODS

We utilized syngeneic mouse models of ovarian cancer (ID8), colon cancer (MC38), malignant melanoma (B16), and liver cancer (Hepa1-6) to assess the combination effect of APG-1387 and anti-PD-1 antibody, including immune-related factors, tumor growth, and survival. MSD V-PLEX validated assays were used to measure in vitro and in vivo cytokine release.

RESULTS

In ID8 ovarian cancer and MC38 colon cancer models, APG-1387 and anti-PD1 antibody had synergistic antitumor effects. In the MC38 model, the combination of APG-1387 and anti-PD-1 antibody significantly inhibited tumor growth (P < 0.0001) and increased the survival rate of tumor-bearing animals (P < 0.001). Moreover, we found that APG-1387 upregulated tumor-infiltrating CD3 + NK1.1 + cells by nearly 2-fold, by promoting tumor cell secretion of IL-12. Blocking IL-12 secretion abrogated the synergistic effects of APG-1387 and anti-PD-1 antibody in both MC38 and ID8 models.

CONCLUSIONS

APG-1387 has the potential to turn "cold tumors" into hot ones by recruiting more CD3 + NK1.1 + cells into certain tumors. Based on these and other data, the safety and therapeutic effect of this combination will be investigated in a phase 1/2 trial in patients with advanced solid tumors or hematologic malignancies (NCT03386526).

The role of microRNA-induced apoptosis in diverse radioresistant cancers

Resistance to cancer radiotherapy is one of the biggest concerns for success in treating and preventing recurrent disease. Malignant tumors may develop when they block genetic mutations associated with apoptosis or abnormal expression of apoptosis; Tumor treatment may induce the expression of apoptosis-related genes to promote tumor cell apoptosis. MicroRNAs have been shown to contribute to forecasting prognosis, distinguishing between cancer subtypes, and affecting treatment outcomes in cancer. Constraining these miRNAs may be an attractive treatment strategy to help overcome radiation resistance. The delivery of these future treatments is still challenging due to the excess downstream targets that each miRNA can control. Understanding the role of miRNAs brings us one step closer to attaining patient treatment and improving patient outcomes. This review summarized the current information on the role of microRNA-induced apoptosis in determining the radiosensitivity of various cancers.

RNA-seq reveals novel mechanistic targets of Livin in bladder cancer

BACKGROUND

Bladder cancer is a very common malignancy with a high recurrence rate. The survival of patients with muscle-invasive bladder cancer is poor, and new therapies are needed. Livin has been reported to be upregulated in bladder cancer and influence the proliferation of cancer cells.

MATERIALS AND METHODS

The Livin gene in human bladder cancer cell line T24 was knocked out, and the differentially expressed genes were identified by RNA-seq and qPCR.

RESULTS

Livin knockdown affects gene expression and has strong negative effects on some cancer-promoting pathways. Furthermore, combined with bladder cancer clinical sample data downloaded from TCGA and GEO, 2 co-up-regulated genes and 58 co-down-regulated genes were identified and validated, which were associated with cancer proliferation and invasion.

CONCLUSION

All these results suggest that Livin plays an important role in bladder cancer and could be a potential anticancer target in clinical therapy.

Subcellular localization of X-linked inhibitor of apoptosis protein (XIAP) in cancer: does that matter?

X-linked inhibitor of apoptosis protein (XIAP) finely tunes the balance between survival and death to control homeostasis. XIAP is found aberrantly expressed in cancer, which has been shown to promote resistance to therapy-induced apoptosis and confer poor outcome. Despite its predominant cytoplasmic localization in human tissues, growing evidence implicates the expression of XIAP in other subcellular compartments in sustaining cancer hallmarks. Herein, we review our current knowledge on the prognostic role of XIAP localization and discuss molecular mechanisms underlying differential biological functions played in each compartment. The comprehension of XIAP subcellular shuttling and functional dynamics might provide the rationale for future anticancer therapeutics.

The transcriptional activity profile of inhibitor apoptosis protein encoding genes in colon cancer patients: A STROBE-compliant study

The inhibitor of apoptosis family proteins (IAPs) plays a crucial role in the process of carcinogenesis by regulating apoptosis and maintaining the tissue balance.In this study, a transcriptomic analysis of IAP-encoding genes in colon cancer was performed using oligonucleotide microarrays.Adenocarcinoma and healthy colon tissue samples were collected from 32 patients (16 females and 16 males) who underwent surgery due to colon cancer. The mRNA was extracted from tissue samples and tested using oligonucleotide microarrays (Affymetrix). The results were validated using the qRT-PCR technique. Hierarchical grouping was used to allocate 37 samples of normalized mRNA concentrations into 4 groups, with statistically significant differences in gene expression between these groups. The group of genes associated with colon cancer, including IAP-encoding gene - BIRC5 (Survivin), was selected for further testing.Our study confirmed an increased expression of BIRC5 in colon cancer tissue when compared to the control group. Increased levels of Neuronal Apoptosis Inhibitory Proteins were detected only in low-stage colon cancer, while the expression of Human X Chromosome-Encoded inhibitor of apoptosis family proteins decreased in colon cancer.The transcriptional activity of IAP-encoding genes varied, depending on the severity of colon cancer. The concentration of mRNA, encoding BIRC5 was elevated in samples obtained from more advanced colon cancer. Hence BIRC5 could be used as a complementary parameter for the diagnosis and prognosis of colon cancer.

Livin/BIRC7 gene expression as a possible diagnostic biomarker for endometrial hyperplasia and carcinoma

BACKGROUND

Livin/BIRC7 is a member of the inhibitors of apoptosis proteins family which are implicated in development of cancer through the inhibition of apoptosis process. This case-control study was intended to investigate livin/BIRC7 gene expression in endometrial hyperplasia and carcinoma and its correlation to some oxidative stress markers in addition to its possible diagnostic performance.

METHODS

This study included 90 participants [30 endometrial hyperplasia patients, 30 endometrial carcinoma patients, and 30 healthy controls]. Livin/BIRC7 gene expression was analyzed using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Serum catalase activity was assessed by enzyme-linked immunosorbent assay (ELISA) and malondialdehyde level was measured by the colorimetric method.

RESULTS

Livin/BIRC7 gene expression was significantly (p < 0.001) higher in endometrial carcinoma from patients with endometrial hyperplasia when compared to controls. A positive correlation was found between livin/BIRC7 expression and serum catalase activity and malondialdehyde level in endometrial hyperplasia and carcinoma. The detection of livin/BIRC7 in endometrial carcinoma has excellent sensitivity and specificity.

CONCLUSIONS

Livin/BIRC7 was overexpressed in endometrial carcinoma with excellent power to differentiate endometrial carcinoma from endometrial hyperplasia or healthy subjects, suggesting that it might be a useful molecular marker for endometrial carcinoma diagnosis.

The Pathogenic Role of PI3K/AKT Pathway in Cancer Onset and Drug Resistance: An Updated Review

The PI3K/AKT pathway is one of the most frequently over-activated intracellular pathways in several human cancers. This pathway, acting on different downstream target proteins, contributes to the carcinogenesis, proliferation, invasion, and metastasis of tumour cells. A multi-level impairment, involving mutation and genetic alteration, aberrant regulation of miRNAs sequences, and abnormal phosphorylation of cascade factors, has been found in multiple cancer types. The deregulation of this pathway counteracts common therapeutic strategies and contributes to multidrug resistance. In this review, we underline the involvement of this pathway in patho-physiological cell survival mechanisms, emphasizing its key role in the development of drug resistance. We also provide an overview of the potential inhibition strategies currently available.

Smac mimetics can provoke lytic cell death that is neither apoptotic nor necroptotic

Smac mimetics, or IAP antagonists, are a class of drugs currently being evaluated as anti-cancer therapeutics. These agents antagonize IAP proteins, including cIAP1/2 and XIAP, to induce cell death via apoptotic or, upon caspase-8 deficiency, necroptotic cell death pathways. Many cancer cells are unresponsive to Smac mimetic treatment as a single agent but can be sensitized to killing in the presence of the cytokine TNFα, provided either exogenously or via autocrine production. We found that high concentrations of a subset of Smac mimetics could provoke death in cells that did not produce TNFα, despite sensitization at lower concentrations by TNFα. The ability of these drugs to kill did not correlate with valency. These cells remained responsive to the lethal effects of Smac mimetics at high concentrations despite genetic or pharmacological impairments in apoptotic, necroptotic, pyroptotic, autophagic and ferroptotic cell death pathways. Analysis of dying cells revealed necrotic morphology, which was accompanied by the release of lactate dehydrogenase and cell membrane rupture without prior phosphatidylserine exposure implying cell lysis, which occurred over a several hours. Our study reveals that cells incapable of autocrine TNFα production are sensitive to some Smac mimetic compounds when used at high concentrations, and this exposure elicits a lytic cell death phenotype that occurs via a mechanism not requiring apoptotic caspases or necroptotic effectors RIPK3 or MLKL. These data reveal the possibility that non-canonical cell death pathways can be triggered by these drugs when applied at high concentrations.

Down-regulation of lncRNA DNAJC3-AS1 inhibits colon cancer via regulating miR-214-3p/LIVIN axis

Long non-coding RNAs (lncRNAs) play a key role in the development and metastasis of cancer. However, the biological role and clinical significance of lncRNA DNAJC3-AS1 in the development of colon cancer is still unknown. In this study, the effects of DNAJC3-AS1 on cell proliferation, migration, and invasion were evaluated by MTT assay, wound-healing assay, and transwell assay, respectively. The relationship between DNAJC3-AS1, miR-214-3p and LIVIN was predicted by the online software and confirmed by dual-luciferase reporter assay. We found that the down-regulation of DNAJC3-AS1 inhibited the proliferation of colon cancer cells and induced growth arrest. Down-regulation of DNAJC3-AS1 also inhibited the migration, invasion, and epithelial-mesenchymal transition (EMT) of colon cancer cells. Moreover, miR-214-3p can bind to DNAJC3-AS1, and knockdown of DNAJC3-AS1 increased miR-214-3p expression in colon cancer cells. LIVIN was identified as a target of miR-214-3p. The up-regulation of miR-214-3p inhibited the protein expression of LIVIN and suppressed the activation of the NF-κB signaling pathway. Besides, down-regulation of DNAJC3-AS1 reduced cell viability, invasion, and EMT of colon cancer cells, while miR-214-3p inhibitor could reverse these effects. The expression of LIVIN and the activation of the NF-κB signaling pathway were suppressed by down-regulating DNAJC3-AS1, while these effects could be restored by miR-214-3p inhibitor. These findings suggested that DNAJC3-AS1 may promote colon cancer progression by regulating the miR-214-3p/LIVIN axis. DNAJC3-AS1 may serve as a new biomarker and therapeutic target for colon cancer, stimulating new research directions and treatment options.

cIAP2 expression and clinical significance in pigmented villonodular synovitis

Pigmented villonodular synovitis (PVNS) is a rare hyperplasia disease of the synovium with a predilection for the knee in either a localized (LPVNS) or a diffuse form (DPVNS). But the exact cause is not clear. The aim of this study was to explore the relationship between the expression of cellular inhibitor of apoptosis 2 (cIAP2) and proliferation, apoptosis, invasive growth and postoperative recurrence in PVNS. Clinical significance of cIAP2 expression in synovium from 63 patients' knee joints with PVNS (40 DPVNS; 23 LPVNS) were investigated with 20 normal subjects acting as controls. The cIAP2 gene was screened by Human Cancer Pathway Finder PCR Array and real-time polymerase chain reaction (RT-PCR). We also used immunohistochemistry to detect cIAP2 and proliferating cell nuclear antigen (PCNA) protein expression and analyzed their relationship with PVNS type, invasive growth, and postoperative recurrence. The expression of cIAP2, PCNA, caspase-8, caspase-9 and caspase-3 protein was tested in Western blot. Screening results of Human Cancer Pathway Finder PCR array and RT-PCR showed significantly more cIAP2 mRNA in DPVNS synovium than in normal or LPVNS synovium (P < 0.05). Immunohistochemistry and western blot showed that the cIAP2 protein expression level in DPVNS was significantly higher than in LPVNS tissue (P < 0.01). As cIAP2 expression increased, the expression of PCNA increased (P < 0.05) and expression of cleaved caspase-3, -8, -9 decreased (P < 0.01). cIAP2 and PCNA overexpression were found to be related to ligament and bone erosion in PVNS and to disease recurrence (P < 0.05). This study suggested that cIAP2 overexpression plays an important role in the anti-apoptotic, proliferative and invasive growth of PVNS, which may account for the recurrence and poor prognosis of DPVNS.

Melatonin and Mesenchymal Stem Cells as a Key for Functional Integrity for Liver Cancer Treatment

Hepatocellular carcinoma (HCC) is the most common hepatobiliary malignancy with limited therapeutic options. On the other hand, melatonin is an indoleamine that modulates a variety of potential therapeutic effects. In addition to its important role in the regulation of sleep–wake rhythms, several previous studies linked the biologic effects of melatonin to various substantial endocrine, neural, immune and antioxidant functions, among others. Furthermore, the effects of melatonin could be influenced through receptor dependent and receptor independent manner. Among the other numerous physiological and therapeutic effects of melatonin, controlling the survival and differentiation of mesenchymal stem cells (MSCs) has been recently discussed. Given its controversial interaction, several previous reports revealed the therapeutic potential of MSCs in controlling the hepatocellular carcinoma (HCC). Taken together, the intention of the present review is to highlight the effects of melatonin and mesenchymal stem cells as a key for functional integrity for liver cancer treatment. We hope to provide solid piece of information that may be helpful in designing novel drug targets to control HCC.

The Multiple Roles of the IAP Super-family in cancer

The Inhibitor of Apoptosis proteins (IAPs) are a family of proteins that are mainly known for their anti-apoptotic activity and ability to directly bind and inhibit caspases. Recent research has however revealed that they have extensive roles in governing numerous other cellular processes. IAPs are known to modulate ubiquitin (Ub)-dependent signaling pathways through their E3 ligase activity and influence activation of nuclear factor κB (NF-κB). In this review, we discuss the involvement of IAPs in individual hallmarks of cancer and the current status of therapies targeting these critical proteins.

Comprehensive molecular characterization of inhibitors of apoptosis proteins (IAPs) for therapeutic targeting in cancer

Background

Inhibitors of apoptosis proteins (IAPs) are a family of antiapoptotic proteins modulating cell cycle, signal transduction and apoptosis. Dysregulated IAPs have been reported to contribute to tumor progression and chemoresistance in various cancers. However, existing studies were sporadic and only focus on one specific cancer with one particular gene in the IAPs family. A systematic investigation on the co-expression pattern, regulation frameworks on various pathways, prognostic utility on patient outcomes, and predictive value on drug sensitivity among all the IAPs across multiple tumor types was lacking.

Methods

Leveraging The Cancer Genome Atlas data with comprehensive genomic characterizations on 9714 patients across 32 tumor types and the Genomics of Drug Sensitivity in Cancer data with both genomic characterizations and drug sensitivity data on > 1000 cell lines, we investigated the co-expression pattern of IAPs, their regulations of apoptosis as well as other pathways and clinical relevance of IAPs for therapeutics development.

Results

We discovered diverse expression pattern among IAPs, varied spectrum of apoptosis regulations through IAPs and extensive regulations beyond apoptosis involving immune response, cell cycle, gene expression and DNA damage repair. Importantly, IAPs were strong prognostic factors for patient survival and tumor stage in several tumor types including brain, liver, kidney, breast and lung cancer. Further, several IAPs were found to be predictive of sensitivity to BCL-2 inhibitors (BIRC3, BIRC5, BIRC6, and BIRC7) as well as RIPK1 inhibitors (BIRC3 and BIRC6).

Conclusion

Together, our work revealed the landscape of regulations, prognostic utilities and therapeutic relevance of IAPs across multiple tumor types.

BIRC7 promotes epithelial-mesenchymal transition and metastasis in papillary thyroid carcinoma through restraining autophagy

Papillary thyroid carcinoma (PTC) is the most common cancer of the endocrine system, which is usually associated with a favorable therapeutic response and prognosis. However, metastatic spreading occurs in around 5% of the PTC patients. Identification of molecular markers could early predict the metastatic potential, which is essential for reducing the patient's overtreatment. Baculoviral IAP Repeat Containing 7 (BIRC7) is an inhibitor of apoptosis protein (IAP) family gene that is known to be linked to tumor progression, but its role in the setting of PTC metastasis remains unknown. This study, therefore, aims to explore the role of BIRC7 in the metastasis and autophagy of PTC and elucidate its underlying molecular mechanisms. BIRC7 expression was assessed in fresh samples of human PTC and normal tissues via qRT-PCR and immunohistochemistry. In addition, BIRC7 was overexpressed and silenced in PTC cell lines followed by transmission electron microscopy, western blotting, immunofluorescence microscopy, wound healing and invasion assays. We further explored the relevance of BIRC7 in vivo using a tumor xenograft model. Our results demonstrated that BIRC7 plays a pro-invasive role in PTC. BIRC7 expression is significantly upregulated in PTC compared with matched thyroid normal tissues. In addition, we found that BIRC7 knockdown induced a significant reduction in PTC cell EMT and metastasis in vitro and in vivo, while overexpression of BIRC7 markedly enhanced PTC cell migration and invasion. Moreover, our data showed that BIRC7 was able to suppress autophagy through modulating the expression of ATG5 and BECN1, and that this suppression is responsible for BIRC7 silence induced suppression of EMT and metastasis of PTC cell. We further found that targeting both BIRC7 and mTOR enhances autophagy in PTC cells and to achieve synergistic antimetastatic efficacy in vitro and in vivo. These findings indicate that the suppression of autophagy by BIRC7 drives the invasion and metastasis of PTC cells, thus suggesting that the activation of autophagy may inhibit metastasis of PTC with high BIRC7 expression.

A pilot study of Livin gene and Yes-associated protein 1 expression in hepatocellular carcinoma patients

Background

Livin gene and Yes-Associated Protein 1 (YAP1 (play a pivotal role in organ size control and tumorigenesis.

Aim

In the present pilot study, we investigate the expression of Livin gene and YAP1 in hepatitis C virus (HCV) associated hepatocellular carcinoma (HCC) compared to other HCV patients and controls.

Methods: the studied patients were divided into three groups 30 patients in each group in addition to 30 healthy subjects as a control group. Relative quantification of Livin gene and YAP-1 were assessed by quantitative Real Time RT-PCR (qPCR) in all studied patients and healthy controls. other laboratory investigations were done including complete blood count (CBC),international normalized ratio (INR) as well as liver function tests and tumor markers.

Results

Significant overexpression of Livin gene and YAP-1 was detected in HCC group followed by Hepatitis C Virus (HCV) untreated group then HCV treated group. The relative quantitation (RQ) of both genes showed positive correlation to the carcinoembryonic antigen (CEA) level and a significant relation was found between higher level of Livin and YAP1 genes and tumor size. The overall survival rate was low in those patients with high levels of Livin and YAP 1 genes so they were considered as indicators of a bad prognosis.

Conclusion

There is overexpression of Livin gene and YAP1 in hepatocellular carcinoma patients. They can be used as indicators of bad prognosis of the disease pathway together with low survival rate.

Sanguinarine Induces Apoptosis Pathway in Multiple Myeloma Cell Lines via Inhibition of the JaK2/STAT3 Signaling

Sanguinarine (SNG), a benzophenanthridine alkaloid, has displayed various anticancer abilities in several vivo and in vitro studies. However, the anticancer potential of SNG is yet to be established in multiple myeloma (MM), a mostly incurable malignancy of plasma cells. In this study, we aimed to investigate the potential anti-proliferative and pro-apoptotic activities of SNG in a panel of MM cell lines (U266, IM9, MM1S, and RPMI-8226). SNG treatment of MM cells resulted in a dose-dependent decrease in cell viability through mitochondrial membrane potential loss and activation of caspase 3, 9, and cleavage of PARP. Pre-treatment of MM cells with a universal caspase inhibitor, Z-VAD-FMK, prevented SNG mediated loss of cell viability, apoptosis, and caspase activation, confirming that SNG-mediated apoptosis is caspase-dependent. The SNG-mediated apoptosis appears to be resulted from suppression of the constitutively active STAT3 with a concomitant increase in expression of protein tyrosine phosphatase (SHP-1). SNG treatment of MM cells leads to down-regulation of the anti-apoptotic proteins including cyclin D, Bcl-2, Bclxl, and XIAP. In addition, it also upregulates pro-apoptotic protein, Bax. SNG mediated cellular DNA damage in MM cell lines by induction of oxidative stress through the generation of reactive oxygen species and depletion of glutathione. Finally, the subtoxic concentration of SNG enhanced the cytotoxic effects of anticancer drugs bortezomib (BTZ) by suppressing the viability of MM cells via induction of caspase-mediated apoptosis. Altogether our findings demonstrate that SNG induces mitochondrial and caspase-dependent apoptosis, generates oxidative stress, and suppresses MM cell lines proliferation. In addition, co-treatment of MM cell lines with sub-toxic doses of SNG and BTZ potentiated the cytotoxic activity. These results would suggest that SNG could be developed into therapeutic agent either alone or in combination with other anticancer drugs in MM.

Ginsenoside Rk1 Induces Apoptosis in Neuroblastoma Cells Through Loss of Mitochondrial Membrane Potential and Activation of Caspases

Neuroblastoma (NB) is the most common childhood cancer, with a very poor prognosis. More than 60% of children with NB die within five years; therefore, a more effective therapy for NB is required. Although ginsenoside has been shown to significantly inhibit the growth of various cancers, the effect of ginsenoside Rk1 on neuroblastoma has not been known yet. Hence, we examined the anticancer effects of highly pure Rk1 on neuroblastoma cell lines. The apoptotic effects of Rk1 on neuroblastoma cells were examined using cell viability assay, flow cytometry and cell staining assay, and the change in gene expression levels were analysed using RT-PCR, western blots, and immunohistochemistry. The metastatic effect of Rk1 was monitored by wound healing assay, invasion and migration with Matrigels. Rk1 inhibited neuroblastoma cell viability dose-dependently. Rk1-induced apoptosis was investigated through nuclear condensation and mitochondrial membrane potential loss, and it showed that Rk1 can induce cell cycle arrest at the G0/G1 phase but also inhibit the metastatic ability of neuroblastoma cells. Moreover, Rk1 (30 mg/kg) injections markedly inhibited xenograft tumor growth. These findings demonstrate that Rk1 might be valuable in the development of anti-cancer agents for neuroblastoma treatment.

Prognostic significance of X-linked inhibitor of apoptosis protein in solid tumors: A systematic review and meta-analysis

X-linked inhibitor of apoptosis protein (XIAP) is aberrantly expressed in solid tumors. Considering conflicting data, we conducted this meta-analysis to investigate its prognostic role. Electronic databases were searched to collect studies about associations between XIAP expressions and survival outcomes. Hazard ratio (HR), odds ratio (OR), and 95% confidence interval (CI) were utilized as effect size estimates. A total of 3,794 patients from 21 published studies were included. The results revealed that high XIAP expressions correlated with age (OR = 2.02; 95% CI, 1.07-3.84), lymph node metastasis (OR = 1.69; 95% CI, 1.02-2.77), histological grade (OR = 2.04; 95% CI, 1.01-4.11), and tumor stage (OR = 2.18; 95% CI, 1.20-3.96). The combined HR revealed that high XIAP expressions associated with poor overall survival (OS) (HR = 1.60; 95% CI, 1.22-2.10). Our study suggested high XIAP expressions may be indicative of poor prognosis in solid tumors.

Prognostic Value of XIAP Level in Patients with Various Cancers: A Systematic Review and Meta-Analysis

Background: X-linked inhibitor of apoptosis protein (XIAP) plays an important role in cancer pathogenesis, which has been found to be overexpressed in multiple human cancers and associated with survival rates. Herein, we performed a meta-analysis to explore the predictive value of XIAP level in patients with various solid tumors. Methods: Relevant articles exploring the relationship between XIAP expression and survival of cancer patients were retrieved in PubMed, PMC, EMBASE and Web of Science published from 2001 to 2018. The combined hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to evaluate the significance. Results: A total of 6554 patients from 40 articles were included in this meta-analysis. It was shown in 37 studies with 4864 cases that the over-expression of XIAP was associated with poorer overall survival (OS) (combined HR=1.61, 95% CI: 1.33-1.96). Meanwhile, 8 studies with 1862 cases revealed that elevated XIAP level predicted shorter disease-free survival (DFS) (HR=2.17, 95% CI: 1.03-4.59). Subgroup analyses showed that higher XIAP detection was related to worse OS in gastric cancer (HR=1.42, 95% CI: 1.18-1.72) and head and neck cancer (HNC) (HR=2.97, 95% CI: 1.97-4.47). Conclusion: Our results suggested that elevated XIAP level seemed to represent an unfavorable prognostic factor for clinical outcomes in cancer patients. However, there were limited studies describing the association between XIAP expression and clinical prognosis in each different type of tumors. Therefore, concrete roles of XIAP in various cancers need to be further explored.

Magnolol Induces Apoptosis and Inhibits ERK-modulated Metastatic Potential in Hepatocellular Carcinoma Cells

BACKGROUND/AIM

The aim of the present study was to evaluate the anti-cancer effect of magnolol in hepatocellular carcinoma (HCC) cells in vitro.

MATERIALS AND METHODS

HCC SK-Hep1 cells were treated with different concentrations of magnolol or PD98059 [extracellular-signal-regulated kinase (ERK) inhibitor] for 48 h, and then cell viability, apoptosis, signal transduction, expression of anti-apoptotic and metastasis-related proteins, and cell invasion were investigated by [3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay, flow cytometry, nuclear factor kappa B (NF-ĸB) reporter gene, western blotting, and cell invasion assays.

RESULTS

Magnolol significantly induced accumulation of sub-G₁ phase and caspase-3 activation and inhibited NF-ĸB activation, cell invasion, expression of phosphorylated ERK (pERK), anti-apoptotic and metastatic-related proteins. ERK inactivation was required for magnolol-induced inhibition of metastatic potential of SK-Hep1 cells.

CONCLUSION

Taken together, these results indicated that magnolol not only induced apoptosis, but also inhibited ERK-modulated metastatic potential of HCC SK-Hep1 cells.

Potential Involvement of BIRC5 in Maintaining Pluripotency and Cell Differentiation of Human Stem Cells

The BIRC5 gene encodes a survivin protein belonging to class III of inhibitors of apoptosis, IAP. This protein serves a dual role. First, it regulates cell death, and second, it is an important regulator of mitosis progression, although its physiological regulatory function has not been fully understood. Many studies have shown and confirmed that survivin is practically absent in mature tissues in nature, while its overexpression has been reported in many cancerous tissues. There is little information about the significance of BIRC5 expression in normal adult human stem cells. This paper presents the study and analysis of survivin expression at the transcription level using qPCR method, in hematopoietic stem cells from peripheral blood mobilized with a granulocyte growth factor, adherent cells derived from the umbilical cord, and normal bone marrow stem cells. The expression of this gene was also examined in the blood of normal healthy individuals. The results of the analysis have shown that the more mature the cells are, the lower the expression of the BIRC5 gene is. The lowest expression has been found in peripheral blood cells, while the highest in normal bone marrow cells. The more the CD34+ and CD105 cells in the tested material are, the higher the BIRC5 expression is. Stem cells from cell culture show higher BIRC5 expression. The study confirms the involvement of BIRC5 from the IAP family in many physiological processes apart from apoptosis inhibition. The possible effect of BIRC5 on cell proliferation; involvement in cell cycle, cell differentiation, survival, and maintenance of stem cells; and the possible effect of IAP on the antineoplastic properties of mesenchymal stem cells have been demonstrated. Our research suggests that BIRC5 may be responsible for the condition of stem cell pluripotency and its high expression may also be responsible for the dedifferentiation of tumor cells.

The SMAC Mimetic APG-1387 Sensitizes Immune-Mediated Cell Apoptosis in Hepatocellular Carcinoma

The inhibitor of apoptosis protein (IAP) genes are frequently overexpressed in malignancies. Second mitochondria-derived activator of caspase (SMAC) mimetics, which target IAPs, have potential to trigger cancer cell death and sensitize tumor cells to cytotoxic therapy. The aim of this study was to investigate the anti-tumor potential of a novel bivalent SMAC mimetic, APG-1387, in hepatocellular carcinoma (HCC). The mRNA and protein expressions of IAPs, including cellular IAPs (cIAP1 and cIAP2) and X chromosome-linked IAP (XIAP), were increased in HCC tumors compared with normal liver tissue. APG-1387 treatment alone significantly reduced the protein levels of IAPs, but had only a modest effect on the viability and apoptosis of HCC cells in vitro. However, APG-1387 in combination with tumor necrosis factor-alpha (TNF-α) or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) significantly reduced cell viability and proliferation, and induced apoptosis in HepG2 cells, as well as in HCCLM3 cells that harbors cancer stem cell-like properties. These synergistic killing effects were caspase-dependent and partially dependent on RIPK1 kinase activity. Furthermore, APG-1387 also promoted the killing effect of Natural Killer cells on HCC cells in vitro and the combination therapy significantly inhibited tumor growth by inducing cell apoptosis in xenograft mice model. In conclusion, our study clarified that APG-1387 could sensitize HCC cells to cytokines or immune cells mediated cell killing and implied that potential of SMAC mimetic based combination immunotherapy for HCC treatment.

Natural compound Tetrocarcin-A downregulates Junctional Adhesion Molecule-A in conjunction with HER2 and inhibitor of apoptosis proteins and inhibits tumor cell growth

Overexpression of the tight junction protein Junctional Adhesion Molecule-A (JAM-A) has been linked to aggressive disease in breast and other cancers, but JAM-targeting drugs remain elusive. Screening of a natural compound library identified the antibiotic Tetrocarcin-A as a novel downregulator of JAM-A and human epidermal growth factor receptor-2 (HER2) protein expression in breast cancer cells. Lysosomal inhibition partially rescued the downregulation of JAM-A and HER2 caused by Tetrocarcin-A, and attenuated its cytotoxic activity. Tetrocarcin-A treatment or JAM-A silencing reduced AKT and ERK phosphorylation, inhibited c-FOS phosphorylation at Threonine-232 (its transcriptional regulation site), inhibited nuclear localization of c-FOS, and downregulated expression of the inhibitor of apoptosis proteins (IAP). This was accompanied by Tetrocarcin-A-induced caspase-dependent apoptosis. To begin evaluating the potential clinical relevance of our findings, we extended our studies to other models. Encouragingly, Tetrocarcin-A downregulated JAM-A expression and caused cytotoxicity in primary breast cells and lung cancer stem cells, and inhibited the growth of xenografts in a semi-in vivo model involving invasion across the chicken egg chorioallantoic membrane. Taken together, our data suggest that Tetrocarcin-A warrants future evaluation as a novel cancer therapeutic by virtue of its ability to downregulate JAM-A expression, reduce tumorigenic signaling and induce apoptosis.

Expression of C19MC miRNAs in HCC associates with stem-cell features and the cancer-testis genes signature

BACKGROUND

Intratumor heterogeneity of hepatocellular carcinoma (HCC) and, among HCC cell subsets, the cancer stem cell population (hCSC), is responsible for therapeutic resistance and disease relapse.

AIMS

To characterize hCSC-enriched HCCs at the molecular level.

METHODS

Side population (SP) was used to identify the hCSCs in multiple tumor sampling from different patients and primary HCCs cultures. FACS was used to immunoprofile cultures. miRNAs were profiled in samples and correlated to SP. The Cancer Genome Atlas (TCGA) HCC dataset was analyzed to search for signatures associated with C19MC miRNAs expression. Results were confirmed by immunohistochemistry.

RESULTS

The miRNA cluster on chromosome 19 (C19MC) was enriched in SP and in HCCs with a high SP fraction. At the molecular level, an elevated C19MC was correlated with expression of precursor transcripts. In TCGA-HCC series, high C19MC expression identified a subset of patients with poorer prognosis, advanced disease and overexpression of the cancer-testis (CT) antigens. These data were confirmed in an independent cohort of HCCs and at the protein level.

CONCLUSION

C19MC miRNAs and CT antigens overexpression represents a novel oncogenic pathway in a subset of hCSC-enriched HCCs with dismal prognosis. CT antigens are promising immunotherapy targets. Therefore, these molecular signatures could identify HCCs who could benefit from immunotherapy.

A novel SMAC mimetic APG-1387 exhibits dual antitumor effect on HBV-positive hepatocellular carcinoma with high expression of cIAP2 by inducing apoptosis and enhancing innate anti-tumor immunity

Check point inhibitor anti-PD1 antibody produced some efficacy in Hepatocellular Carcinoma (HCC) patients previously treated with sorafenib. Unfortunately, HCC patients with hepatitis B virus (HBV) infection did not respond as well as uninfected patients. Previously, Second mitochondria-derived activator of caspases (SMAC) mimetics-the antagonist for inhibitor of apoptosis proteins (IAPs) can rapidly reduce serum hepatitis B virus DNA in animal model. APG-1387 is a novel SMAC-mimetic, small molecule inhibitor targeting inhibitor of apoptosis proteins (IAPs). In our study, firstly, we found that HCC patients with copy number alteration of cIAP1, cIAP2, and XIAP had a dismal prognosis. Then, we discovered that APG-1387 alone could induce apoptosis of PLC/PRF/5 which was HBV positive both in-vitro and in-vivo. Furthermore, we found that APG-1387 significantly up-regulated the expression of calreticulin and HLA-DR in PLC/PRF/5 via activating non-classic NF-κB pathway. Also, compared to vehicle group, APG-1387 increased NK cell counts by 5 folds in PLC/PRF/5 xenograft model. In-vitro, APG-1387 positively regulated T cells by reducing Treg differentiation and down-regulating PD1 expression in CD4 T cell. Moreover, APG-1387 had no impact on memory T cells. Consequently, our results suggest that APG1387 could be a good candidate to combine with anti-PD1 antibody treatment to overcome low responds of check point inhibitors in HBV positive HCC.

Overcoming chemotherapy drug resistance by targeting inhibitors of apoptosis proteins (IAPs)

Inhibitors of apoptosis (IAPs) are a family of proteins that play a significant role in the control of programmed cell death (PCD). PCD is essential to maintain healthy cell turnover within tissue but also to fight disease or infection. Uninhibited, IAPs can suppress apoptosis and promote cell cycle progression. Therefore, it is unsurprising that cancer cells demonstrate significantly elevated expression levels of IAPs, resulting in improved cell survival, enhanced tumor growth and subsequent metastasis. Therapies to target IAPs in cancer has garnered substantial scientific interest and as resistance to anti-cancer agents becomes more prevalent, targeting IAPs has become an increasingly attractive strategy to re-sensitize cancer cells to chemotherapies, antibody based-therapies and TRAIL therapy. Antagonism strategies to modulate the actions of XIAP, cIAP1/2 and survivin are the central focus of current research and this review highlights advances within this field with particular emphasis upon the development and specificity of second mitochondria-derived activator of caspase (SMAC) mimetics (synthetic analogs of endogenously expressed inhibitors of IAPs SMAC/DIABLO). While we highlight the potential of SMAC mimetics as effective single agent or combinatory therapies to treat cancer we also discuss the likely clinical implications of resistance to SMAC mimetic therapy, occasionally observed in cancer cell lines.

Identification of mTOR as a primary resistance factor of the IAP antagonist AT406 in hepatocellular carcinoma cells

Dysregulation of inhibitor of apoptosis (IAP) proteins (IAPs) in hepatocellular carcinoma (HCC) is often associated with poor prognosis. Here we showed that AT406, an IAP antagonist, was cytotoxic and pro-apoptotic to both established (HepG2, SMMC-7721 lines) and primary HCC cells. Activation of mTOR could be a key resistance factor of AT406 in HCC cells. mTOR inhibition (by OSI-027), kinase-dead mutation or knockdown remarkably enhanced AT406-induced lethality in HCC cells. Reversely, forced-activation of mTOR by adding SC79 or exogenous expressing a constitutively active S6K1 (T389E) attenuated AT406-induced cytotoxicity against HCC cells. We showed that AT406 induced degradation of IAPs (cIAP-1 and XIAP), but didn't affect another anti-apoptosis protein Mcl-1. Co-treatment of OSI-027 caused simultaneous Mcl-1 downregulation to overcome AT406's resistance. Significantly, shRNA knockdown of Mcl-1 remarkably facilitated AT406-induced apoptosis in HCC cells. In vivo, AT406 oral administration suppressed HepG2 tumor growth in nude mice. Its activity was potentiated with co-administration of OSI-027. We conclude that mTOR could be a key resistance factor of AT406 in HCC cells.

Overexpression of Smac/DIABLO in Hep-2 Cell Line: Possible Role in Potentiating the Sensitivity of Chemotherapeutic Drugs

Aims and background

The major obstacles for tumor chemotherapy are drug resistance and/or adverse effects on the host. In the present study we investigated the role of the second mitochondria-derived activator of caspase (Smac/DIABLO) in the action of cisplatin (DDP), 5-fluorouracil (5-FU), and the combination of both in Hep-2 cells.

Methods and study design

Hep-2 laryngeal carcinoma cells exposed to DDP, 5-FU and the combination of both were investigated. Cell viability was determined by MTT assay. Apoptosis was measured by Ho.33342 and PI double staining and flow cytometry. The expression of Smac/DIABLO at the mRNA and protein level was assayed by RT-PCR and Western blotting.

Results

DDP, 5-FU and the combination of both drugs reduced the cell survival rates in a concentration- and time-dependent manner. The drug combination not only exerted a stronger inhibitory effect, but also at a lower concentration compared with the single drugs. Apoptosis was concomitant in a caspase-dependent manner. The expression of Smac/DIABLO increased significantly at both mRNA and protein levels after cell exposure to the combination compared with single drugs.

Conclusions

Smac/DIABLO plays a pivotal role in attaining a synergistic effect in Hep-2 cells in response to this combined strategy.

shRNA-armed conditionally replicative adenoviruses: a promising approach for cancer therapy

The small-interfering RNAs (siRNAs) have been employed to knockdown the expression of cancer-associated genes and shown some promise in cancer therapy. However, synthetic siRNA duplexes or plasmid mediated delivery of siRNAs have several problems, such as short half-life, low transfection efficiency and cytotoxicity associated with transfection. Conditionally replicating adenovirus (CRAds) as the delivery vector for short hairpin RNAs (shRNAs) could overcome these limitations and have shown augmented anti-tumor effects in experimental studies and preclinical trials. In this review, we summarize recent progress in the development of CRAds-shRNA for cancer treatment. Combination of CRAds-shRNA with chemotherapeutics, radiation, dendritic cells, monoclonal antibodies and small-molecule inhibitors will be necessary to eradicate cancer cells and cancer stem cells and achieve superior outcomes. The use of CRAd platform for efficient delivery of shRNAs and foreign genes will open a new avenue for cancer therapy.

Alcoholic hepatitis versus non-alcoholic steatohepatitis: Levels of expression of some proteins involved in tumorigenesis

Non-alcoholic steatohepatitis (NASH) is commonly associated with obesity, type 2 diabetes, and/or hypertriglyceridemia, while alcoholic steatohepatitis (ASH) is associated with alcohol abuse. Both NASH and ASH patients can develop cirrhosis and hepatocellular carcinoma (HCC) if left untreated. However, the rate of tumorigenesis in NASH and ASH appears to be different. Individuals with NASH progress to HCC at a rate of 0.5% annually (Lindenmeyer and McCullough, 2018), when individuals with ASH progress to HCC at a rate of 3-10% annually (Schwartz and Reinus, 2012). Thus, the objective of our study is to determine if there are differences in NASH versus ASH in the levels of different proteins expressed involved in cancer development. The method used was measuring the proteins expressed in liver biopsied sections from NASH and ASH patients using immunohistochemical staining with fluorescent antibodies and then quantitating the fluorescence intensity morphometrically. The 20 proteins tested are parts of the Ingenuity Canonical Pathway of Molecular Mechanisms of Cancer and include: RAP2B, NAIP, FYN, PAK6, SUV39H1, GNAI1, BAX, E2F3, CKDN2B, BAK1, BCL2, DIABLO, RASGRF2, GNA15, PIK3CB, BRCA1, MAP2K1, BIRC3, CDK2, and ATM. In ASH, the proteins that showed upregulated levels of expression were SUV39H1, E2F3, BCL2, BAK1, BIRC3, and GNAI1. In NASH, the proteins that showed upregulated levels of expression were BAK1 and GNAI1 and the protein that showed downregulated level of expression was BCL2. Additionally, levels of expression for SUV39H1, E2F3, BCL2, BAK1, BIRC3, and GNAI1 were significant upregulated in ASH compared to NASH. These results showed significant differences in ASH compared to normal liver, and significant differences in ASH compared to NASH. Thus, we conclude that there are more proteins involved in tumorigenesis in ASH compared to NASH and in ASH compared to normal liver, which is consistent with the known tumor development rate in ASH and NASH.

NLRC and NLRX gene family mRNA expression and prognostic value in hepatocellular carcinoma

Nucleotide‐binding oligomerization domain (NOD)‐like receptor (NLR)C and NLRX family proteins play a key role in the innate immune response. The relationship between these proteins and hepatocellular carcinoma (HCC) remains unclear. This study investigated the prognostic significance of NLRC and NLRX family protein levels in HCC patients. Data from 360 HCC patients in The Cancer Genome Atlas database and 231 patients in the Gene Expression Omnibus database were analyzed. Kaplan–Meier analysis and a Cox regression model were used to determine median survival time (MST) and overall and recurrence‐free survival by calculating the hazard ratio (HR) and 95% confidence interval (CI). High NOD2 and low NLRX1 expression in tumor tissue was associated with short MST (P = 0.012 and 0.014, respectively). A joint‐effects analysis of NOD2 and NLRX1 combined revealed that groups III and IV had reduced risk of death from HCC as compared to group I (adjusted P = 0.001, adjusted HR = 0.31, 95% CI = 0.16–0.61 and adjusted P = 0.043, adjusted HR = 0.63, 95%CI = 0.41–0.99, respectively). NOD2 and NLRX1 expression levels are potential prognostic markers in HCC following hepatectomy.

XIAP over-expression is an independent poor prognostic marker in Middle Eastern breast cancer and can be targeted to induce efficient apoptosis

Background

Breast cancer is the most common cancer in females and is ranked second in cancer-related deaths all over the world in women. Despite improvement in diagnosis, the survival rate of this disease has still not improved. X-linked Inhibitor of Apoptosis (XIAP) has been shown to be over-expressed in various cancers leading to poor overall survival. However, the role of XIAP in breast cancer from Middle Eastern region has not been fully explored.

Methods

We examined the expression of XIAP in more than 1000 Middle Eastern breast cancer cases by immunohistochemistry. Apoptosis was measured by flow cytometry. Protein expression was determined by western blotting. Finally, in vivo studies were performed on nude mice following xenografting and treatment with inhibitors.

Results

XIAP was found to be over-expressed in 29.5% of cases and directly associated with clinical parameters such as tumor size, extra nodal extension, triple negative breast cancer and poorly differentiated breast cancer subtype. In addition, XIAP over-expression was also significantly associated with PI3-kinase pathway protein; p-AKT, proliferative marker; Ki-67 and anti-apoptotic marker; PARP. XIAP over-expression in our cohort of breast cancer was an independent poor prognostic marker in multivariate analysis. Next, we investigated inhibition of XIAP using a specific inhibitor; embelin and found that embelin treatment led to inhibition of cell viability and induction of apoptosis in breast cancer cells. Finally, breast cancer cells treated with combination of embelin and PI3-kinase inhibitor; LY294002 synergistically induced apoptosis and caused tumor growth regression in vivo.

Conclusion

These data suggest that XIAP may be playing an important role in the pathogenesis of breast cancer and can be therapeutically targeted either alone or in combination with PI3-kinase inhibition to induce efficient apoptosis in breast cancer cells.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3627-4) contains supplementary material, which is available to authorized users.

XAF1 expression levels in a non-small cell lung cancer cohort and its potential association with carcinogenesis

The process of lung carcinogenesis is still not well understood and involves different levels of regulation of several genes. The search for molecular biomarkers, which can be applicable to clinical practice, has been the focus of various studies. XIAP-associated factor 1 (XAF1) was previously shown to be downregulated in many types of tumors, including squamous cell lung cancer. XAF1 is a pro-apoptotic protein and its restoration was found to sensitize cancer cells to apoptotic stimuli; however, the precise mechanism involved in the downregulation of XAF1 in tumors is unknown and promoter hypermethylation or heat-shock transcription factor 1 (HSF1) may be involved. Therefore, the aim of the present study was to evaluate the expression of XAF1 in tumors and adjacent non-tumor specimens from non-small cell lung cancer (NSCLC) patients, and its potential association with various factors including clinicopathological characteristics and other genes involved in NSCLC. Our results indicated that XAF1 expression was markedly altered in NSCLC tumor samples when compared to that found in normal lung tissues. Predominantly, XAF1 was downregulated in the tumors, except in never-smoker patients. In addition, XAF1 may also be important in the whole cell stress mechanism where the p53 status is crucial.

YM155 Down-Regulates Survivin and Induces P53 Up-Regulated Modulator of Apoptosis (PUMA)-Dependent in Oral Squamous Cell Carcinoma Cells

BACKGROUND YM155, which inhibits the anti-apoptotic protein survivin, is known to exert anti-tumor effects in various cancers. However, there were few reports describing the inhibitory effect of YM155 on human oral squamous cell carcinoma (OSCC) cells that highly express survivin. In this study, we investigated the anti-tumor effects of YM155 on OSCC cells and then examined its molecular mechanisms. MATERIAL AND METHODS SCC9 cells of OSCC were treated with series of concentrations of YM155 (0.01, 0.1, 1, and 10 ng/ml) for 6, 12, and 24 h. The effect of YM155 on survival of SCC9 cells was detected by MTT and colony formation assay. Cell apoptosis was detected by flow cytometric analysis and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assays. Western blot was used to detect the protein expression of survivin, p53, and PUMA. Caspase-3 activity was measured by cleavage of the caspase-3 substrate. To test the role of PUMA and caspase-3 on YM155-induced apoptosis and growth inhibition, the SCC9 cells was transfected with PUMA siRNA or caspase-3 siRNA or control siRNA for 16 h before YM155 (1 and 10 ng/ml) treatment for 24 h. In addition, we also investigated the effect of YM155 in an in vivo xenograft model. RESULTS Treatment of YM155 efficiently reduced survivin expression and increased PUMA expression and caspase-3 activation in the SCC9 cells. YM155 treatment resulted in 18-86% decrease in cell viability, 10-60% decrease in colony numbers, and 8-40% increase in cell apoptosis (p<0.05 and p<0.01). However, the induction of cell apoptosis growth inhibition was reversed by PUMA siRNA or caspase-3 transfection. In addition, animals treated with YM155 showed more than 60% tumor growth inhibition compared to the controls (p<0.05). CONCLUSIONS YM155 is a potent inhibitor of progression of SCC9 cells, which could be due to attenuation of survivin, and activation of the PUMA/caspase-3 cellular signaling processes. This study suggests that YM155 may be a potential molecular target with therapeutic relevance for the treatment of OSCC.

Hepatoprotective Mongolian prescription II enhances the antitumor effects of chemotherapeutics in hepatocellular carcinoma xenografts

Hepatoprotective Mongolian prescription II (MPII), a mixture of 18 different medicinal herbs, significantly inhibited the growth of human liver cancer cell lines Huh-7 and HepG2 in vitro with different concentrations; MPII (6mg/mL) inhibited cell proliferation by 80.48%. MPII induced apoptosis in both cell lines, which was observed by light microscopy and flow cytometry. MPII-induced apoptosis and G0/G1 cell cycle arrest were quantified by Annexin V-FITC/PI staining and flow cytometry. At the molecular level, MPII induced caspase-3, caspase-8, caspase-9, and cytochrome c gene expression. In vivo, MPII dramatically inhibited human liver tumor growth in a xenograft model in Kunming mice with no apparent cytotoxicity to the hosts. Apoptotic genes (Bcl-2 and Bax) are up-regulated, suggesting that the ratio of Bcl-2/Bax was statistically significant, indicating that the drugs had affected the expression of apoptosis genes, especially on induce apoptosis gene Bax. We also observed an attenuated effect when MPII was used in combination with chemotherapy drug 5-fluorouracil (5-FU). The mice treated with 5-FU alone did not show a concentration-dependent effect, but 5-FU in combination with MPII displayed concentration-dependent effects on liver cancer cells. Our study suggests that MPII works by inducing apoptosis and cell cycle arrest, and has the potential to be a powerful anticancer agent.

Melatonin, a Full Service Anti-Cancer Agent: Inhibition of Initiation, Progression and Metastasis

There is highly credible evidence that melatonin mitigates cancer at the initiation, progression and metastasis phases. In many cases, the molecular mechanisms underpinning these inhibitory actions have been proposed. What is rather perplexing, however, is the large number of processes by which melatonin reportedly restrains cancer development and growth. These diverse actions suggest that what is being observed are merely epiphenomena of an underlying more fundamental action of melatonin that remains to be disclosed. Some of the arresting actions of melatonin on cancer are clearly membrane receptor-mediated while others are membrane receptor-independent and involve direct intracellular actions of this ubiquitously-distributed molecule. While the emphasis of melatonin/cancer research has been on the role of the indoleamine in restraining breast cancer, this is changing quickly with many cancer types having been shown to be susceptible to inhibition by melatonin. There are several facets of this research which could have immediate applications at the clinical level. Many studies have shown that melatonin's co-administration improves the sensitivity of cancers to inhibition by conventional drugs. Even more important are the findings that melatonin renders cancers previously totally resistant to treatment sensitive to these same therapies. Melatonin also inhibits molecular processes associated with metastasis by limiting the entrance of cancer cells into the vascular system and preventing them from establishing secondary growths at distant sites. This is of particular importance since cancer metastasis often significantly contributes to death of the patient. Another area that deserves additional consideration is related to the capacity of melatonin in reducing the toxic consequences of anti-cancer drugs while increasing their efficacy. Although this information has been available for more than a decade, it has not been adequately exploited at the clinical level. Even if the only beneficial actions of melatonin in cancer patients are its ability to attenuate acute and long-term drug toxicity, melatonin should be used to improve the physical wellbeing of the patients. The experimental findings, however, suggest that the advantages of using melatonin as a co-treatment with conventional cancer therapies would far exceed improvements in the wellbeing of the patients.

From big data to diagnosis and prognosis: gene expression signatures in liver hepatocellular carcinoma

Background

Liver hepatocellular carcinoma accounts for the overwhelming majority of primary liver cancers and its belated diagnosis and poor prognosis call for novel biomarkers to be discovered, which, in the era of big data, innovative bioinformatics and computational techniques can prove to be highly helpful in.

Methods

Big data aggregated from The Cancer Genome Atlas and Natural Language Processing were integrated to generate differentially expressed genes. Relevant signaling pathways of differentially expressed genes went through Gene Ontology enrichment analysis, Kyoto Encyclopedia of Genes and Genomes and Panther pathway enrichment analysis and protein-protein interaction network. The pathway ranked high in the enrichment analysis was further investigated, and selected genes with top priority were evaluated and assessed in terms of their diagnostic and prognostic values.

Results

A list of 389 genes was generated by overlapping genes from The Cancer Genome Atlas and Natural Language Processing. Three pathways demonstrated top priorities, and the one with specific associations with cancers, ‘pathways in cancer,’ was analyzed with its four highlighted genes, namely, BIRC5, E2F1, CCNE1, and CDKN2A, which were validated using Oncomine. The detection pool composed of the four genes presented satisfactory diagnostic power with an outstanding integrated AUC of 0.990 (95% CI [0.982–0.998], P < 0.001, sensitivity: 96.0%, specificity: 96.5%). BIRC5 (P = 0.021) and CCNE1 (P = 0.027) were associated with poor prognosis, while CDKN2A (P = 0.066) and E2F1 (P = 0.088) demonstrated no statistically significant differences.

Discussion

The study illustrates liver hepatocellular carcinoma gene signatures, related pathways and networks from the perspective of big data, featuring the cancer-specific pathway with priority, ‘pathways in cancer.’ The detection pool of the four highlighted genes, namely BIRC5, E2F1, CCNE1 and CDKN2A, should be further investigated given its high evidence level of diagnosis, whereas the prognostic powers of BIRC5 and CCNE1 are equally attractive and worthy of attention.

Regorafenib induces extrinsic and intrinsic apoptosis through inhibition of ERK/NF-κB activation in hepatocellular carcinoma cells

The aim of the present study was to investigate the role of NF-κB inactivation in regorafenib-induced apoptosis in human hepatocellular carcinoma SK-HEP-1 cells. SK-HEP-1 cells were treated with different concentrations of the NF-κB inhibitor 4-N-[2-(4-phenoxyphenyl)ethyl]quinazoline-4,6-diamine (QNZ) or regorafenib for different periods. The effects of QNZ and regorafenib on cell viability, expression of NF-κB-modulated anti-apoptotic proteins and apoptotic pathways were analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blotting, DNA gel electrophoresis, flow cytometry and NF-κB reporter gene assay. Inhibitors of various kinases including AKT, c-Jun N-terminal kinase (JNK), P38 and extracellular signal-regulated kinase (ERK) were used to evaluate the mechanism of regorafenib-induced NF-κB inactivation. The results demonstrated that both QNZ and regorafenib significantly inhibited the expression of anti-apoptotic proteins and triggered extrinsic and intrinsic apoptosis. We also demonstrated that regorafenib inhibited NF-κB activation through ERK dephosphorylation. Taken all together, our findings indicate that regorafenib triggers extrinsic and intrinsic apoptosis through suppression of ERK/NF-κB activation in SK-HEP-1 cells.

T-3256336, a novel and orally available small molecule IAP antagonist, induced tumor cell death via induction of systemic TNF alpha production

Inhibitors of apoptosis proteins (IAPs) are a family of antiapoptotic regulators that have attracted attention as potential targets for cancer therapeutics. Although recent studies have revealed that small-molecule IAP antagonists induce tumor selective cell death in an autocrine tumor necrosis factor (TNF)α-dependent manner, the single-agent efficacy of IAP antagonists is restricted to a small subset of cancer cells. In this study, we showed that the single-agent activity of T-3256336 was limited to a few cancer cell lines in vitro, and these cell lines were defined by relatively high levels of TNFα mRNA expression. However, some other cancer cells, including PANC-1 cells, become drastically sensitive to T-3256336 when costimulated with exogenous TNFα. In PANC-1 mouse xenograft models, the administration of T-3256336 increased levels of several cytokines including TNFα and lead to tumor regression as a single agent, which was attenuated by the neutralization of circulating mouse TNFα with an antibody. These results suggest dual roles of IAP antagonists, increase systemic cytokines including TNFα, and sensitization of tumors to IAP antagonist-induced death.

CYLD downregulates Livin and synergistically improves gemcitabine chemosensitivity and decreases migratory/invasive potential in bladder cancer: the effect is autophagy-associated

Although GC (gemcitabine and cisplatin) chemotherapy remains an effective method for treating bladder cancer (BCa), chemoresistance is a major obstacle in chemotherapy. In this study, we determined whether gemcitabine resistance correlates with migratory/invasive potential in BCa and whether this relationship is regulated by the cylindromatosis (CYLD)-Livin module. First, we independently investigated the correlation of CYLD/Livin and gemcitabine resistance with the potential for tumor migration and invasiveness. Second, we found that co-transfected CYLD and Livin dramatically improved sensitivity to gemcitabine chemotherapy and decreased migration/invasion potential. Next, we determined that CYLD may regulate Livin by the NF-κB-dependent pathway. We also found that CYLD overexpression and Livin knockdown might improve gemcitabine chemosensitivity by decreasing autophagy and increasing apoptosis in BCa cells. Finally, the effects of CYLD-Livin on tumor growth in vivo were evaluated. Our study demonstrates that CYLD-Livin might represent a potential therapeutic for chemoresistant BCa.

The effects of Livin shRNA on the response to cisplatin in HepG2 cells

Hepatocellular carcinoma is a lethal malignancy with poor prognosis, partially due to tumor metastasis, recurrence and resistance to chemo- or radio-therapy. Cisplatin can inhibit cancer cell DNA replication, and is widely used in the clinical treatment of tumors. The present study aimed to generate eukaryotic expression vectors for Livin shRNA and to examine the effects of Livin shRNA on the chemosensitivity of HepG2 hepatocellular carcinoma cells. Eukaryotic expression vectors for Livin shRNA (pSD11-U6/Neo/GFP/Livin) were designed and constructed. The HepG2 hepatocellular carcinoma cell line was transfected with this vector using the liposome method. The expression levels of Livin mRNA and protein were measured by quantitative polymerase chain reaction and western blot analysis. The rate of cell growth inhibition was measured using MTT assay following treatment of the cells with cisplatin (2.0 mg/l). DNA sequencing confirmed that the construction of the eukaryotic expression vector for Livin shRNA had been successful. Transfection of these vectors into HepG2 cells led to a significant reduction in the expression levels of Livin mRNA and protein (P<0.05). Cisplatin treatment was associated with significantly higher rates of cell growth inhibition in HepG2 cells transfected with Livin shRNA compared with those that were not transfected (P<0.05). The vectors constructed in the present study produced effective inhibition of the Livin gene in HepG2 cells and increased the chemosensitivity of hepatocellular carcinoma cells.

Non-coding RNAs in Mammary Gland Development and Disease

Non-coding RNAs (ncRNAs) are untranslated RNA molecules that function to regulate the expression of numerous genes and associated biochemical pathways and cellular functions. NcRNAs include small interfering RNAs (siRNAs), microRNAs (miRNAs), PIWI-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs) and long non-coding RNAs (lncRNAs). They participate in the regulation of all developmental processes and are frequently aberrantly expressed or functionally defective in disease. This Chapter will focus on the role of ncRNAs, in particular miRNAs and lncRNAs, in mammary gland development and disease.

Oxymatrine and cancer therapy

Oxymatrine is a kind of alkaloid extracted from traditional Chinese herb Sophora flavescens Ait. It has been proved to exert various biological activities such as anti-angiogenesis, proliferation-inhibiting, apoptosis-promoting, analgesic-strengthening, and anti-metastasis. The biological activities are related with inhibition of angiogenesis-associated factors, regulation of related signaling pathway and protein expression, synergistic effects with chemotherapy drug, cell cycle arrest and inhibition of voltage-activated K+ channel. In this review, we summarize the recent investigations of oxymatrine in cancer therapy so as to provide references for further study and clinical therapy.

Apoptosis in liver carcinogenesis and chemotherapy

Hepatocellular carcinoma (HCC) is a major health problem. In human hepatocarcinogenesis, the balance between cell death and proliferation is deregulated, tipping the scales for a situation where antiapoptotic signals are overpowering the death-triggering stimuli. HCC cells harbor a wide variety of mutations that alter the regulation of apoptosis and hence the response to chemotherapeutical drugs, making them resistant to the proapoptotic signals. Considering all these modifications found in HCC cells, therapeutic approaches need to be carefully studied in order to specifically target the antiapoptotic signals. This review deals with the recent relevant contributions reporting molecular alterations for HCC that lead to a deregulation of apoptosis, as well as the challenge of death-inducing chemotherapeutics in current HCC treatment.

Expression of livin, survivin and caspase-3 in prostatic cancer and their clinical significance

To explore the expressions level of Livin, Survivin and Caspase-3 in prostatic cancer and the relationship among the 3 proteins and the clinicopathological features as well as the correlation among them. Totally, 43 paraffin-embedded prostate cancer tissues obtained from patients who were performed with rectal prostate biopsy or excision and 17 paraffin-embedded prostatic hyperplasia tissues were collected. All the specimens were confirmed by pathology. Immunohistochemistry SP method was used to detect the expressions of Livin, Survivin and Caspase-3 in prostatic cancer compared to hyperplasia tissues. The positive expression rates of both Livin and Survivin in prostatic cancer tissue were higher than those in prostatic hyperplasia tissue (93.02% vs. 64.70%, P < 0.05; 83.72% vs. 35.29%, P < 0.01). However, the positive expression rate of Caspase-3 in prostatic cancer tissue was obviously lower than that in prostatic hyperplasia tissue (25.58% vs. 58.82%, P < 0.01). Both Livin and Survivin expressions in prostatic cancer tissue were related to pathological grading (Gleason scores) (X(2) = 14.000, P = 0.001), but not related to preoperative PSA, clinical stages and distant metastasis (P > 0.05). Capsase-3 expression in prostatic cancer tissue was related to pathological grading (Gleason scores) (X (2) = 14.000, P = 0.001) and clinical stages (X (2) = 4.896, P = 0.027), but not related to preoperative PSA and distant metastasis (P > 0.05). In prostatic cancer tissue, Livin expression had no correlation with Survivin expression (r = 0.127, P = 0.419 > 0.05), but negatively correlated with Caspase-3 expression (r = -0.497, P = 0.001). Survivin expression was negatively correlated with Caspase-3 expression (r = -0.354, P = 0.020). Livin, Survivin and Caspase-3 are closely related to the occurrence and development of prostatic cancer and which are expected to become new targets for diagnosis and treatment in future.

The ubiquitin-proteasome system and its potential application in hepatocellular carcinoma therapy

The ubiquitin-proteasome system (UPS) is a complicated tightly controlled system in charge of degrading 80-90% of proteins, and is central to regulating cellular function and keeping protein homeostasis. Therefore, the components of UPS attract considerable attention as potential targets for hepatocellular carcinoma (HCC) therapy. The clinical success of bortezomib in multiple myeloma and mantle cell lymphoma patients has set the precedent for therapeutically targeting this pathway. This review will provide an overview of the UPS in HCC and the current status of therapeutic strategies.