Protective Mechanisms of Various Active Substances on Cell DNA Damage and Apoptosis Induced by Deoxynivalenol

Deoxynivalenol (DON) is a secondary metabolite of fungi that is harmful to humans and animals. This study examined the protective effects of natural substances, including resveratrol, quercetin, vitamin E, vitamin C, and microbe-derived antioxidants (MA), on both human gastric mucosal cells (GES-1) and pig small intestinal epithelial cells (IPEC-1) when induced by DON. Cells were incubated with active substances for 3 h and then exposed to DON for 24 h. The oxidative stress index, cell cycle, and apoptosis were measured. As compared to cells treated only with DON, pretreatment with active substances improved the balance of the redox status in cells caused by DON. Specifically, quercetin, vitamin E, vitamin C, and MA showed the potential to alleviate the G2 phase cell cycle arrest effect that was induced by DON in both kinds of cells. It was observed that vitamin E and vitamin C can alleviate DON-induced apoptosis and the G2 phase cycle arrest effect mediated via the ATM-Chk 2-Cdc 25C and ATM-P53 signaling pathways in GES-1 cells. In IPEC-1 cells, vitamin C and MA can alleviate both DON-induced apoptosis and the G2 phase cycle arrest effect via the ATM-Chk 2-Cdc 25C signaling pathway. Different bioactive substances utilize different protective mechanisms against DON in interacting with different cells. The proper addition of vitamin E and vitamin C to food can neutralize the toxic effect of DON, while the addition of vitamin C and MA to animal feed can reduce the harm DON does to animals.

PCC0208057 as a small molecule inhibitor of TRPC6 in the treatment of prostate cancer

Prostate cancer (PCa) is a common malignant tumor, whose morbidity and mortality keep the top three in the male-related tumors in developed countries. Abnormal ion channels, such as transient receptor potential canonical 6 (TRPC6), are reported to be involved in the carcinogenesis and progress of prostate cancer and have become potential drug targets against prostate cancer. Here, we report a novel small molecule inhibitor of TRPC6, designated as PCC0208057, which can suppress the proliferation and migration of prostate cancer cells in vitro, and inhibit the formation of Human umbilical vein endothelial cells cell lumen. PCC0208057 can effectively inhibit the growth of xenograft tumor in vivo. Molecular mechanism studies revealed that PCC0208057 could directly bind and inhibit the activity of TRPC6, which then induces the prostate cancer cells arrested in G2/M phase via enhancing the phosphorylation of Nuclear Factor of Activated T Cells (NFAT) and Cdc2. Taken together, our study describes for the first time that PCC0208057, a novel TRPC6 inhibitor, might be a promising lead compound for treatment of prostate cancer.

Hesperetin Inhibits Bladder Cancer Cell Proliferation and Promotes Apoptosis and Cycle Arrest by PI3K/AKT/FoxO3a and ER Stress-mitochondria Pathways

BACKGROUND AND OBJECTIVES

Hesperetin (HSE) is a natural flavonoid derived from the hydrolysis of Hesperidin, which is mainly found in traditional natural Chinese herbs, such as Chenpi and Hovenia caryophyllus. HSE displays anti-inflammatory and antioxidant activities. However, its potential mechanism of action on bladder cancer (BLCA) remains unknown. The aim of this study was to investigate the potential mechanism of action of HSE on BLCA cells.

METHODS

Network pharmacology analysis was used to construct a composite target network, combined with Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis to identify HSE-induced cell death patterns and signaling pathway alterations. Cytotoxicity evaluation was determined by CCK-8 assay. A clone formation assay was performed to assess cell proliferative capacity. Scratch and Transwell assays were performed to evaluate cell migration and invasion ability. Hoechst 33342 staining was visualized to observe morphological features of apoptosis. Apoptosis, cycle distribution, reactive oxygen species (ROS) generation, and mitochondrial membrane potential (MMP) changes were examined by flow cytometry. Western blot analysis was performed to analyze the expression of key proteins associated with cell proliferation, apoptosis, cycle block, PI3K/AKT/FoxO3a and endoplasmic reticulum (ER) stress-mitochondrial pathways.

RESULTS

Network pharmacology analysis was performed to identify 155 potential candidate targets of HSE-BLCA, and further topological analysis was performed to obtain 34 hub-gene. Enrichment analysis yielded patterns of death and key pathways, revealing that the anti-BLCA effect of HSE may be related to the positive regulation of PI3K/AKT/FoxO3a and ER stress-mitochondrial pathways. in vitro results showed that HSE blocked cell proliferation, migration, and invasion in a concentration-dependent manner and triggered apoptosis, G0/G1 phase blockade, ROS production, and MMP depolarization. In addition, Western blot results showed that HSE downregulated phosphorylated (p)-3-phosphoinositide-dependent kinase-1 (PI3K), phosphorylated (p)-AKT serine/threonine kinase 1 (AKT), phosphorylated (p)-Forkhead box O 3a (FoxO3a), anti-apoptotic proteins, proliferation-associated proteins, and cell cycle promoters, whereas the levels of proteins related to the expression of cell cycle regulators, pro-apoptotic proteins, and ER stress-mitochondrial pathway were up-regulated in BLCA cells by the intervention of HSE. PI3K agonist (YS-49) and ER stress inhibitor (4-PBA) partially or completely reversed HSE-mediated proliferation, apoptosis, and cycle blockade in BLCA cells.

CONCLUSION

The anticancer effects of HSE in BLCA may be attributed to its coordination of actions, inhibiting cell proliferation, migration, and invasion, inducing apoptosis, G0/G1 phase arrest, generating reactive oxygen species, causing MMP loss, and engaging the caspase protein family. These actions are likely mediated through the PI3K/AKT/FoxO3a and ER stress-mitochondrial pathways. Thus, our findings suggest that HSE is a promising novel therapeutic candidate for the prevention and treatment of BLCA.

[Paeoniflorin induces apoptosis and cycle arrest in B-cell acute lymphoblastic leukemia cells by inhibiting SENP1/c-Myc signaling pathway]

The effect of paeoniflorin on apoptosis and cell cycle in human B-cell acute lymphoblastic leukemia(B-ALL) and its underlying mechanism were investigated in this study. Nalm-6 and SUP-B15 cells were cultured in vitro and divided into control group(0 μg·mL~(-1)) and experimental groups(200, 400, and 800 μg·mL~(-1) paeoniflorin). Cell counting kit-8(CCK-8) was used to measure the viability of Nalm-6 and SUP-B15 cells, and cell apoptosis and cell cycle distribution were analyzed by flow cytometry. Western blot was used to detect the protein levels of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase(cleaved PARP), c-Myc, and small ubiquitin-like modifier-specific protease 1(SENP1). The mRNA levels of c-Myc and SENP1 in acute lymphoblastic leukemia(ALL) patients were analyzed based on the Oncomine database. AutoDock was used for molecular docking to analyze the interaction of paeoniflorin with c-Myc and SENP1 proteins. RESULTS:: showed that paeoniflorin inhibited the viability of Nalm-6 and SUP-B15 cells in concentration and time-dependent manners. Compared with the control group, paeoniflorin significantly up-regulated the expression of apoptosis-related proteins cleaved caspase-3 and cleaved PARP to induce apoptosis, evidently increased the proportion of G_2/M phase cells and induced G_2/M phase arrest, and obviously down-regulated the expression of c-Myc and SENP1 proteins in Nalm-6 and SUP-B15 cells. The mRNA levels of c-Myc and SENP1 in ALL patients were higher than those in the normal cell. Molecular docking demonstrated that paeoniflorin had good binding to c-Myc and SENP1 proteins. In summary, paeoniflorin inhibits the proliferation of Nalm-6 and SUP-B15 cells by inducing apoptosis and G_2/M phase arrest, which may be related to the down-regulation of c-Myc and SENP1 proteins.

Neochamaejasmine A promotes apoptosis and cell cycle arrest in B16F10 melanoma cells via JNK and p38 MAPK signaling pathway

BACKGROUND

The incidence of melanoma is increasing over the last 30 years. The most common treatments, such as surgery, chemotherapy, and radiotherapy, frequently cause serious damage to the body. It is therefore critical to develop a new therapeutic strategy for the treatment of melanoma.

OBJECTIVES

This research aims to evaluate the anti-tumor effect of Neochamaejasmine A (NCA) on B16F10 melanoma cells and the underlying molecular mechanisms.

METHODS

The CCK-8 kit was utilized to assay the influence of NCA on the vitality of B16F10 cells. Modifications in morphology B16F10 cells were observed using a phase-contrast microscope. Apoptosis of B16F10 melanoma cells was assessed by Hoechst 33258, Annexin V and propidium iodide staining. Cell cycle was detected using a commercial kit by flow cytometry. The mRNA and protein expression levels associated with apoptosis and cell cycle arrest were detected by RT-PCR and Western blot. The expression level of pathway proteins was assessed using Western blot.

RESULT

It was found that the proliferation of B16F10 cells was inhibited by NCA in concentration- and time-dependent manners. NCA promoted apoptosis by halting the cell cycle at the G2/M phase. After treatment with NCA, cell apoptosis was confirmed by Hoechst 33258 staining. NCA triggered the cell cycle to seize at the G2/M stage by downregulating cyclin B1 and cyclin-dependent kinase 2 (CDC2) expression. Moreover, the mRNA and protein expression of cleaved caspase-9 and Bcl-2-associated X-protein (Bax) were increased, whereas there was a decline in the expression of B-cell lymphoma 2 (Bcl-2). The p-p38/p38 and phosphorylated c-Jun N-terminal kinase (p-JNK/JNK) ratio were also elevated by NCA. The apoptosis and G2/M cell cycle arrest were inhibited in cells co-treated with the p38 inhibitor SB203580 and JNK inhibitor SP600125. The expression of apoptosis- related proteins Bax was decreased and Bcl-2 was increased.

CONCLUSION

The findings of this study showed that NCA could induce apoptosis and cell cycle arrest in B16F10 melanoma cells by activating JNK and p38 MAPK signaling pathway.

The role of E2A in ATPR-induced cell differentiation and cycle arrest in acute myeloid leukaemia cells

Acute myeloid leukaemia (AML) is a biologically heterogeneous disease with an overall poor prognosis; thus, novel therapeutic approaches are needed. Our previous studies showed that 4-amino-2-trifluoromethyl-phenyl retinate (ATPR), a new derivative of all-trans retinoic acid (ATRA), could induce AML cell differentiation and cycle arrest. The current study aimed to determine the potential pharmacological mechanisms of ATPR therapies against AML. Our findings showed that E2A was overexpressed in AML specimens and cell lines, and mediate AML development by inactivating the P53 pathway. The findings indicated that E2A expression and activity decreased with ATPR treatment. Furthermore, we determined that E2A inhibition could enhance the effect of ATPR-induced AML cell differentiation and cycle arrest, whereas E2A overexpression could reverse this effect, suggesting that the E2A gene plays a crucial role in AML. We identified P53 and c-Myc were downstream pathways and targets for silencing E2A cells using RNA sequencing, which are involved in the progression of AML. Taken together, these results confirmed that ATPR inhibited the expression of E2A/c-Myc, which led to the activation of the P53 pathway, and induced cell differentiation and cycle arrest in AML.

Increased LINC00922 in preeclampsia regulates the proliferation, invasion, and migration of placental trophoblast cells

Background

Recent studies have shown that the abnormal expression of long-chain non-coding RNAs (lncRNAs) can significantly affect the biological function of trophoblast cells and lead to the occurrence of preeclampsia (PE). This study explores the expression of lncRNA LINC00922 in PE and its effect on the function of placental trophoblast cells, along with the corresponding molecular mechanism, providing a theoretical basis and molecular target for understanding the occurrence, early diagnosis, and targeted therapy of PE.

Methods

Fluorescence quantitative PCR was used to detect the expression of LINC00922 in 30 cases of PE tissues and normal tissues. The CCK-8 assay, clone formation experiment, and flow cytometry were used to detect the effects of LINC00922 knockdown or overexpression on the proliferation, colony formation, and cell cycle of HTR-8/SVneo placental trophoblast cells. The Transwell assay was used to detect the effects of LINC00922 knockdown or overexpression on the invasion and migration of HTR 8/SVneo cells, and western blot was used to detect the expression of cell cycle-related proteins and invasion and migration-related proteins.

Results

LINC00922 was highly expressed in PE tissues. Knockdown of LINC00922 significantly inhibited the proliferation, invasion, and migration of HTR-8/SVneo cells, along with colony formation and the ability to induce cell cycle arrest in the G0/G1 phase. However, overexpression of LINC00922 had the opposite effect. Knockdown or overexpression of LINC00922 significantly affected the expression of cell cycle-related proteins cyclin-dependent kinase 2 (CDK2), G1/S-specific cyclin-D1 (Cyclin D1), p21, proliferating cell nuclear antigen (PCNA), matrix metallopeptidase 9 (MMP-9), vimentin, and E-cadherin, but had no significant effect on the expression of matrix metallopeptidase 2 (MMP-2).

Conclusions

LINC00922 was highly expressed in PE, and functional experiments showed that LINC00922 could significantly affect the proliferation and invasion abilities of placental trophoblast cells, suggesting that LINC00922 may play an important role in the occurrence, early diagnosis, and treatment of PE.

Insight Into the Molecular Mechanism of Podophyllotoxin Derivatives as Anticancer Drugs

Podophyllotoxin (PTOX) is a biologically active compound derived from the podophyllum plant, and both it and its derivatives possess excellent antitumor activity. The PTOX derivatives etoposide (VP-16) and teniposide (VM-26) have been approved by the U.S. Food and Drug Administration (FDA) for cancer treatment, but are far from perfect. Hence, numerous PTOX derivatives have been developed to address the major limitations of PTOX, such as systemic toxicity, drug resistance, and low bioavailability. Regarding their anticancer mechanism, extensive studies have revealed that PTOX derivatives can induce cell cycle G2/M arrest and DNA/RNA breaks by targeting tubulin and topoisomerase II, respectively. However, few studies are dedicated to exploring the interactions between PTOX derivatives and downstream cancer-related signaling pathways, which is reasonably important for gaining insight into the role of PTOX. This review provides a comprehensive analysis of the role of PTOX derivatives in the biological behavior of tumors and potential molecular signaling pathways, aiming to help researchers design and develop better PTOX derivatives.

Low expression of long non-coding RNA ARAP1-AS1 can inhibit lung cancer proliferation by inducing G0/G1 cell cycle organization

Background

This paper examines the expression, function, and molecular mechanism of long non-coding ribonucleic acid (lncRNA) ARAP1 antisense RNA 1 (ARAP1-AS1) in lung cancer. Specifically, it aims to clarify the molecular mechanism of lncRNA ARAP1-AS1 that affects the occurrence and development of lung cancer, and provide a theoretical basis and molecular targets for targeted therapy or early diagnosis of lung cancer.

Methods

Fluorescence quantitative detection of lncRNA ARAP1-AS1 expression in lung cancer tissues and cell lines, and methylthiazolyldiphenyl-tetrazolium (MTT), plate cloning experiment, and flow cytometry were used to detect the effect of knockdown of lncRNA ARAP1-AS1 on cell proliferation, clone formation, and the cell cycle, respectively. Western blotting was used to detect the expression of cell cycle-related proteins as well as the effect of knockdown of lncRNA ARAP1-AS1 on lung cancer. Cell proliferation was assessed by a nude mouse subcutaneous tumor formation experiment.

Results

LncRNA ARAP1-AS1 is highly expressed in lung cancer tissues and cells. Knockdown of LncRNA ARAP1-AS1 can significantly inhibit the proliferation and clonal formation of lung cancer cells and induce G0/G1 cell cycle arrest. Knockdown of ARAP1-AS1 can markedly inhibit the expression of cell cycle-related protein cyclin D1, but has no significant effect on the expression of cyclin-dependent kinase (CDK)4 and CDK6. Furthermore, knockdown of ARAP1-AS1 can also notably inhibit the growth of lung cancer cells and substantially reduce the expression of Ki-67 in tumor-bearing tissues in nude mice.

Conclusions

LncRNA ARAP1-AS1 is highly expressed in lung cancer. Knocking down of this gene can significantly inhibit cell proliferation in vitro and in vivo, and can also cause G0/G1 cell cycle arrest by inhibiting the expression of cyclin D1.

[Mechanism of psoralen in aggravating hepatotoxicity induced by CCl_4 by delaying liver regeneration]

This study aimed to investigate whether psoralen can aggravate hepatotoxicity induced by carbon tetrachloride(CCl_4) by inducing hepatocyte cycle arrest and delaying liver regeneration. Female C57 BL/6 mice aged 6-8 weeks were randomly divided into control group, model group(CCl_4 group), combined group(CCl_4+PSO group) and psoralen group(PSO group). CCl_4 group and CCl_4+PSO group were given CCl_4 intraperitoneally at a dose of 100 μL·kg~(-1) once; olive oil of the same volume was given to control group and PSO group intraperitoneally; 12 h, 36 h and 60 h after CCl_4 injection, PSO group and CCl_4+PSO group were administrated with PSO intragastrically at a dose of 200 mg·kg~(-1); 0.5% CMC-Na of the same volume was administrated to control group and PSO group intragastrically. The weight of mice was recorded every day. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were measured at 36 h, 60 h and 84 h after CCl_4 injection. Mice were sacrificed after collection of the last serum samples. Liver samples were collected, and liver weight was recorded. Histopathological and morphological changes of liver were observed by haematoxylin and eosin staining. The mRNA levels of HGF, TGF-β, TNF-α, p53 and p21 in liver were detected by RT-qPCR. Western blot was used to detect the levels of cell cycle-related proteins. According to the results, significant increase of serum ALT and AST and centrilobular necrosis with massive inflammatory cell infiltration were observed in CCl_4+PSO group. After PSO administration in CCl_4 model, the mRNA levels of HGF(hepatocyte growth factor) and TNF-α were reduced, while the mRNA expressions of TGF-β, p53 and p21 was up-regulated. The expression of PCNA(proliferating cell nuclear antigen) was significantly increased in CCl_4 and CCl_4+PSO group, while the relative protein level in CCl_4+PSO group was slightly lower than that in CCl_4 group. Compared with control and CCl_4 group, the expression of p27(cyclic dependent kinase inhibitor protein p27) was prominently increased in CCl_4+PSO group. These results indicated that hepatotoxicity induced by CCl_4 could be aggravated by intraperitoneal administration with PSO, and the repair process of liver could be delayed. The preliminary mechanism may be related to the inhibition of PCNA and regulation of some cell cycle-associated protein by psoralen, in which the significant up-regulation of p27, p53 and p21 may play important roles.

Notopterol-induced apoptosis and differentiation in human acute myeloid leukemia HL-60 cells

Purpose: This study aims to observe the effects of notopterol on the apoptosis and differentiation of HL-60 cells and to explore the underlying molecular mechanisms.

Methods: Cell viability was assessed using sulforhodamine B assay. Cell proliferation was determined by the trypan blue dye exclusion test. Colony-forming units were assayed in methylcellulose. Apoptosis assays were carried out by annexin V-fluorescein isothiocyanate(FITC)/propidium iodide (PI) double staining, Hoechst 33342 staining, mitochondrial membrane potential, and Western blot. Wright–Giemsa staining, nitroblue tetrazolium (NBT) reduction assay, CD11b and CD14 and Western blot were detected for induction of differentiation. In addition, cell-cycle phase distribution was analyzed by flow cytometry and Western blot. The combination therapy of notopterol and all-trans retinoic acid (ATRA) on HL-60 cells was examined.

Results: Notopterol obviously inhibited the growth of HL-60 cells with an IC₅₀ value of 40.32 μM and remarkably reduced the number of colonies by 10, 20, and 40 µM. In addtion, notopterol induced the percentage of apoptotic HL-60 cells, reduced the mitochondrial membrane potential, decreased the protein expresstion of Bcl-2 and Mcl-1, and increased the expression of Bax, cleavage of caspase 9, caspase 3, and PARP. As for cell differentiation, notopterol clearly induced chromatin condensation; increased the nucleocytoplasmic ratio, nitroblue tetrazolium-positive cells, expression of CD14 and CD11b, and protein expression of c-Jun and Jun B, and decreased c-myc. Furthermore, notopterol induced the G0/G1 cell-cycle arrest as determined using flow cytometry, which may be related to the regulation of cell-cycle-related proteins p53, CDK2, CDK4, Cyclin D1, Cyclin E, and survivin. The combined use of notopterol and ATRA did not enhance the apoptotic effect as evidenced by cell viability test and Hoechst 33342. However, the combination of notopterol and ATRA enhanced the effect of inducing differentiation when compared with using either notopterol or ATRA alone, which can be evidenced by the increased nucleocytoplasmic ratio, NBT positive cells, and expression of CD14.

Conclusion: This is the first time it has been demonstrated that notopterol could induce apoptosis, differentiation, and G0/G1 arrest in human AML HL-60 cells, suggesting that notopterol has potential therapeutic effects on AML. The combination application of notopterol (20 and 40 μM) and ATRA (2 μM) could augment differentiation of HL-60 cells.

Psoralen Induced Liver Injury by Attenuating Liver Regenerative Capability

Psoralen is a major component of the common traditional Chinese medicine Fructus Psoraleae (FP). In this study, we focused on psoralen to explore FP-induced hepatotoxicity and the underlying mechanisms. The acute oral median lethal dose of psoralen in ICR mice was determined to be 1,673 mg/kg. C57BL/6 mice were administered psoralen intragastrically at doses of 400 mg/kg or 800 mg/kg, and were sacrificed 24 h after treatment. Changes in various hepatotoxicity indicators demonstrated that psoralen can cause mild liver injury in mice. Psoralen inhibited the viability of normal human liver L02 cells in vitro by inducing S-phase arrest. In addition, psoralen in both the mouse livers and L02 cells upregulated cyclin E1 and p27 protein levels. The 2/3 partial hepatectomy mouse model was used to further explore the effects of psoralen on the liver regeneration and hepatocellular cycle arrest in vivo. The results showed that the decrease of liver regenerative and self-healing capabilities induced by hepatocellular cycle arrest may play an important role in the hepatotoxicity of psoralen. The further mechanism researches indicated that psoralen-induced hepatotoxicity was associated with inhibition of mTOR signalling pathway and mitochondrial injury; furthermore, MHY, an mTOR activator, partly alleviated the inhibition of mTOR and S-phase cycle arrest induced by psoralen in L02 cells. In conclusion, in this study we showed for the first time, that psoralen significantly induced liver injury in mice; the decrease of liver regenerative and compensatory capabilities induced by hepatocellular cycle arrest may play an important role in the progression of hepatotoxicity associated with the upregulation of cyclin E1 and p27, as well as the inhibition of mTOR signalling and mitochondrial injury. Our findings may contribute to the reduction of hepatotoxicity risk induced by Fructus Psoraleae.

Bufalin suppresses the proliferation and metastasis of renal cell carcinoma by inhibiting the PI3K/Akt/mTOR signaling pathway

Bufalin, one of the active ingredients of the Chinese drug Chan su, exhibits significant antitumor activity against various cancer types. However, the role of bufalin in renal cell carcinoma (RCC) remains unclear. In the present study, it was demonstrated that bufalin inhibited cell proliferation, blocked the cell cycle in the G2/M phase, and reduced the metastasis of human RCC ACHN cells via the upregulation of p21^waf/cip1 and E-cadherin and the downregulation of cyclin dependent kinase 1, cyclin B1, N-cadherin, and hypoxia-inducible factor-1α (HIF-1α). Further mechanistic study revealed that bufalin reduced the expression of phosphorylated (phospho)-Akt and phospho-mammalian target of rapamycin (mTOR). Moreover, HIF-1α expression may be regulated through the inhibition of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mTOR signaling pathway. Thus, the present results suggest that bufalin induces cell cycle arrest and suppresses metastasis; this process may be associated with the PI3K/Akt/mTOR signaling pathway. Accordingly, it is suggested that bufalin is a therapeutic agent for RCC.

HOTAIR contributes to the growth of liver cancer via targeting miR-217

Non-coding RNAs are important in the progression of liver cancer. The present study aimed to investigate the effects of long non-coding RNA HOX transcript antisense RNA (HOTAIR) on the proliferation of liver cancer and the association between HOTAIR and microRNA (miR)-217. It was demonstrated that the expression of HOTAIR was upregulated in liver cancer tissues and 3 liver cancer cell lines (MHCC97H, HepG2 and Hep3B). Inhibition of HOTAIR with HOTAIR small interfering (si) RNA lentiviral vectors significantly suppressed the cell proliferation of HepG2 cells, and downregulated the protein expression levels of two proliferation markers, Ki67 and proliferating cell nuclear antigen (PCNA). Furthermore, inhibition of HOTAIR induced G0/G1 cycle arrest by increasing the expression of p27 and decreasing the expression of cyclin D1. It was then predicted and verified that miR-217 was the target of HOTAIR. Expression of miR-217 was downregulated in liver cancer tissues and the 3 liver cancer cell lines. Further results revealed that inhibition of HOTAIR markedly upregulated the expression of miR-217 in HepG2 cells, and miR-217 inhibitor-induced reduction of miR-217 was significantly suppressed by HOTAIR inhibition. Furthermore, the increased cell proliferation and growth, the upregulated expression of Ki67 and PCNA, and the reduced G0/G1 cycle arrest induced by miR-217 inhibitor were partly rescued by inhibition of HOTAIR. Finally, the in vivo experiment indicated that HOTAIR inhibition suppressed tumorigenesis, including the smaller tumor volume and the reduced levels of Ki67. Overall, HOTAIR contributes to the proliferation and growth of liver cancer via downregulation of miR-217.

Advances in molecular signaling mechanisms of β-phenethyl isothiocyanate antitumor effects

β-Phenethyl isothiocyanate (PEITC) is an important phytochemical from cruciferous vegetables and is being evaluated for chemotherapeutic activity in early phase clinical trials. Moreover, studies in cell culture and in animals found that the anticarcinogenic activities of PEITC involved all the major stages of tumor growth: initiation, promotion, and progression. A number of mechanisms have been proposed for the chemopreventive activities of this compound. Here, we focus on the major molecular signaling pathways for the anticancer activities of PEITC. These include (1) activation of apoptosis pathways; (2) induction of cell cycle arrest; and (3) inhibition of the survival pathways. Furthermore, we also discussed the regulation of drug-metabolizing enzymes, including cytochrome P450s, metabolizing enzymes, and multidrug resistance.