Cells In G1 Phase Research Articles

Discovery of pyrido[3,4-b]indol-1-one derivatives as novel non-covalent Bruton’s tyrosine kinase (BTK) inhibitors

Bruton’s tyrosine kinase (BTK) is an attractive target for the treatment of malignancy and inflammatory/autoimmune diseases. Most of the covalent BTK inhibitors would induce off-target side effects and drug resistance. To improve the drug safety of BTK inhibitors, non-covalent inhibitors have attracted more and more attention. We designed a series of novel pyrido[3,4-b]indol-1-one derivatives (N-A and N-B) via scaffold hopping from CGI-1746. The structure–activity relationship (SAR) of the newly-synthesized compounds was explored. The results showed that compounds 12 and 18 exhibited potent enzymatic potency against BTK with IC50 values of 0.22 μM and 0.19 μM, respectively. In lymphoma cell lines U-937 cells and Ramos cells, compounds 12 and 18 displayed comparative antiproliferative activity with Ibrutinib. Moreover, compound 12 induced G1-phase cell cycle arrest and apoptosis in U-937 cells. And it could effectively inhibit tumor growth in U-937 xenograft mouse model (TGI = 41.90% at 50 mg/kg). In all, the new pyrido[3,4-b]indol-1-one derivatives have the antitumor potency by BTK inhibition and were worthy of further exploration.

Combination of auraptene and arsenic trioxide induces apoptosis and cellular accumulation in the subG1 phase in adult T-cell leukemia cells.

Objective(s):Despite advances in the treatment of adult T-cell leukemia/lymphoma (ATLL), the survival rate of this malignancy remains significantly low. Auraptene (AUR) is a natural coumarin with broad-spectrum anticancer activities. To introduce a more effective therapeutic strategy for ATLL, we investigated the combinatorial effects of AUR and arsenic trioxide (ATO) on MT-2 cells.Materials and Methods:The cells were treated with different concentrations of AUR for 24, 48, and 72 hr, and viability was measured by alamarBlue assay. Then, the combination of AUR (20 μg/ml) and ATO (3 μg/ml) was administrated and the cell cycle was analyzed by PI staining followed by flow cytometry analysis. In addition, the expression of NF-κB (REL-A), CD44, c-MYC, and BMI-1 was evaluated via qPCR.Results:Assessment of cell viability revealed increased toxicity of AUR and ATO when used in combination. Our findings were confirmed by accumulation of cells in the sub G1 phase of the cell cycle and significant down-regulation of NF-κB (REL-A), CD44, c-MYC, and BMI-1.Conclusion:Obtained findings suggest that combinatorial use of AUR and ATO could be considered for designing novel chemotherapy regimens for ATLL.

Molecular mechanism of CK19 involved in the regulation of postoperative recurrence of HBV-associated primary hepatocellular carcinoma in Guangxi.

BackgroundCytokeratin 19 (CK19/KRT19) is a marker of biliary epithelial cells and hepatic progenitor cells, which can be expressed in some hepatocellular carcinoma (HCC). However, its role in the occurrence, development, and recurrence of hepatitis B virus (HBV)-associated HCC remains to be clarified. This study is to analyze the relationship between the expression of CK19 protein and clinicopathological factors, as well as the effect of positive CK19 expression on the prognosis of HCC patients.MethodsSmall interfering RNA (siRNA) transfection was used to silence CK19 in MHCC-97H and Hep-3B. Real time polymerase chain reaction (qPCR), immunohistochemistry (IHC), and flow cytometry were used to detect the effects of CK19 silencing on cell function. High-throughput sequencing was used to explore the potential molecular mechanism of CK19 positive expression of HCC.ResultsIn 24 patients with HCC, CK19 was only expressed in cancer tissues, regardless of primary or recurrent tumors, and the positive expression rate of recurrent tumors was higher than that of primary tumors. The HCC participants with positive primary CK19 expression had a shorter tumor-free survival time. Silencing of the CK19 gene in MHCC-97H and Hep-3B attenuated the migration and invasion ability of MHCC-97H, increased the G2 phase cell content of MHCC-97H and Hep-3B, and increased the proportion of apoptosis. High-throughput sequencing results suggested that changes in the function of the cell cycle regulating genes, drug, and carcinogenic metabolism might be the potential pathways of CK19 in regulating the biological behavior of HCC.ConclusionsAmong HBV-related recurrent HCC, the positive rate of CK19 expression in recurrent HCC tumors was higher, and the tumor-free survival time of HCC patients with positive CK19 expression in primary HCC was shorter. After silencing of the CK19 gene, the migration and invasion ability of HCC cells were weakened, the content of G2-M cell cycle cells was increased, the invasion and migration of HCC cells were inhibited, and apoptosis was promoted. Changes in the function of the cell cycle regulating genes and the regulation of drug and carcinogenic metabolites-related pathways may be the pathways through which CK19 affects the biological behavior of HCC.

Dual mTORC1/2 inhibitor AZD2014 diminishes myeloid-derived suppressor cells accumulation in ovarian cancer and delays tumor growth.

Mechanistic target of rapamycin (mTOR) forms two distinct complexes, mTOR complex 1 (mTORC1) and mTORC2. Here we investigated the antitumor effect of dual mTORC1/2 inhibitor AZD2014 on epithelial ovarian cancer (EOC) and its potential effect on immunosuppressive myeloid-derived suppressor cells (MDSCs). Immunohistochemical analysis of mTORC1 and mTORC2 was performed on a human ovarian cancer tissue microarray. High mTORC2 expression level was associated with shorter survival in EOC, whereas mTORC1 was not correlate with patients' prognosis. AZD2014 suppressed mTOR signaling pathway in ovarian cancer cells, inhibited proliferation and induced G1-phase cell cycle arrest and apoptosis. In tumor-bearing mice, AZD2014 treatment limited tumor growth, reduced peritoneal ascites, and prolonged survival. AZD2014 specifically reduced MDSCs migration and accumulation in EOC peritoneal fluid but not in the spleen. Moreover, subsequent AZD2014 treatment after cisplatin chemotherapy delayed EOC recurrence. Collectively, we observed that high mTORC2 expression level in EOC indicated a poor prognosis. Remarkably, in tumor-bearing mice, AZD2014 diminished MDSC accumulation and delayed tumor growth and recurrence.

Straightforward access to novel mitochondriotropics derived from 2-arylethanol as potent and selective antiproliferative agents

The necessity for developing novel cytostatic agents with improved activities and reduced side-effects to tackle cancer prompted us to investigate mitochondria-targeted compounds, an approach that is gaining attention for the selective transportation of cytotoxic agents.We envisioned the possibility of conjugating a phenethyl alcohol motif, decorated with a series of phenol-based substituents on the aryl moiety, with a triphenyl phosphonium scaffold (a mitochondria-directed vector), through a hydrocarbon chain of different lengths. Thus, such compounds that incorporate the phenethyl skeleton can be considered as masked phenolic compounds derived from relevant natural counterparts found in olive tree (e.g. tyrosol, hydroxytyrosol).Title compounds exhibited very strong in vitro antiproliferative activities against the panel of six human tumor cell lines tested, with GI50 values ranging from the nanomolar (0.026 ± 0.010 μM for 36) to the submicromolar range in most of the cases; this represents an improvement of up to 350-fold compared to classical chemotherapeutic agents, like 5-fluorouracil or cisplatin. Interestingly, decrease in the linker length led to an increase of GI50 values against non-tumor cells, thus allowing a remarkable improvement of selectivity (SI up to 269).The very promising antiproliferative activities prompted us to further investigate their behaviour against multidrug resistant cell lines (MDR). The results indicated a reduced sensitivity of the multidrug resistant cells to compounds, probably due to P-gp-mediated efflux of these antiproliferative agents. Interestingly, activities were completely restored to the same levels by co-administration of tariquidar, a well-known inhibitor of P-gp.Flow cytometry analysis on sensitive cell lines revealed a decrease in the percentage of cells in G1 phase accompanied by increase in S and G2/M phases. In addition, a significant increase in subG1 area, was observed. These results are compatible with the necrotic and apoptotic cell death detected in the Annexin V assay, and with the depolarization of the mitochondria membrane.Thus, the new mitochondriotropic agents reported herein can be considered as promising antiproliferative agents, endowed with remarkable potency and selectivity, including MDR cells, upon co-administration with a pump-efflux inhibitor.

CBIO-12. KAT5 ACTIVITY CONTROLS GLIOBLASTOMA CELL CYCLE DYNAMICS AND TUMOR GROWTH

Abstract Current standard of care therapy for glioblastoma (GB) includes cytoreduction followed by ablative therapies that target rapidly dividing cell types. However, non-cycling, quiescent-like states (G0 phase cells) are present in both normal tissue and tumors and play important roles in maintaining heterogeneity and cellular hierarchies. The presence of quiescent-like/G0 states therefore represents a natural reservoir of tumor cells that are resistant to current treatments. Quiescence or G0 phase is a reversible state of “stasis” cells enter in response to developmental or environmental cues. However, it remains largely unclear to what degree or by what mechanisms tumor cells enter into or exit from quiescent-like states. To gain insight into how GB cells might regulate G0-like states, we performed a genome-wide CRISPR-Cas9 screen in patient-derived GB stem-like cells (GSCs) harboring a G0 reporter construct, which is stabilized when cells enter a G0-like state. Among the top screen hits were members of the Tip60/KAT5 histone acetyltransferase complex, including KAT5 itself. Remarkably, we show that knockout of KAT5 in vitro and in vivo dramatically increases G0 subpopulations in GSC cultures and GSC-induced tumors. Using genetically engineered GSC harboring KAT5 under the control of a Doxycyclin-titratable promoter, we establish that incrementally down regulating KAT5 activity is sufficient to slow cell cycle dynamics causing a build-up G0-like cells; and that partial inhibition of KAT5 leads to extended (mouse) patient survival. Further, in primary tumors, cell-based KAT5 activity assays revealed that high grade tumors harbor larger cell subpopulations with higher KAT5 activity than lower grade tumors. In summary, our results suggest that Tip60/KAT5 activity plays key roles in G0 ingress/egress for GBM tumors, may contribute to tumor progression, and may provide novel therapeutic opportunities.

EXTH-11. COLD ATMOSPHERIC PLASMA SELECTIVELY INDUCES APOPTOSIS AND FERROPTOSIS THROUGH REACTIVE OXYGEN SPECIES IN HIGH-GRADE GLIOMA

Abstract INTRODUCTION Cold atmospheric plasma (CAP) selectively induces reactive oxygen and nitrogen species (ROS/RNS) in many types of cancerous cells. ROS-mediated lipid peroxidation is thought to induce ferroptosis, apoptosis, and autophagy. We hypothesize that ferroptosis and apoptosis are key mechanisms of CAP-mediated cytotoxicity in high-grade glioma (HGG). METHODS B16, U87, GL261, EPD-210FHTC and human astrocyte NHA hTERT cells were treated with CAP for 10, 30, 60, 90, and 180 seconds. Proliferation and propidium iodide (PI)/annexin V flow cytometry assays were employed to quantify cytotoxicity, cell cycle phases and apoptosis. Mitochondrial superoxide concentration was measured using MitoSOX Red. Cells were pre-treated with ferroptosis inhibitors Ferrostatin-1 and Deferoxamine (DFO) in rescue assays. RESULTS Survival of GL261 and U87 cells after 90 seconds of CAP treatment was 3.7% and 7%, respectively, compared to 62% in NHA cells. A CAP dose-dependent increase in mitochondrial superoxide concentration was observed in GL261 and NHA (R2=0.88 and 0.99, respectively). A shift of EPD and NHA cells into G0 phase was noted after 180 seconds of treatment, compared to baseline (55.4% versus 1.2%, 100% vs. 27.5% respectively). Early apoptosis was more prominent in NHA cells (79% of dead cells), and late apoptosis in EPD cells after 60 seconds of treatment (86% of dead cells). DFO pre-treatment significantly reduced CAP cytotoxicity in GL261 (93% vs. 58% after 10 seconds) and U87 cells (85% vs. 13% after 60 seconds). DFO pre-treatment had no effect on NHA response to CAP. CONCLUSION CAP treatment induces dose-dependent increases in ROS and apoptosis in HGG lines tested more significantly than in NHA cells. CAP induces G1-phase cell cycle arrest in treated HGG cells and G0 arrest in non-cancerous cells. CAP-mediated cytotoxicity was significantly mitigated with DFO pre-treatment in HGG cells, suggesting that ferroptosis plays a critical role in the mechanism of CAP treatment in HGG.

A Phase 1, Open-Label, Dose-Escalation Study of the Safety and Efficacy of Anti-CD38 Antibody Drug Conjugate (STI-6129) in Patients with Relapsed or Refractory Multiple Myeloma

Background: With the advent of several new agents in the treatment of multiple myeloma, including proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), and anti-CD38 monoclonal antibodies (mAb), the overall survival (OS) has significantly improved in the past two decades. However, most patients become refractory to currently available therapies along the disease trajectory. The median OS in triple-class-refractory patients (i.e., anti-CD 38 mAb, PIs, and IMiDs) is 6 months (Gandhi et al. Leukemia. 2019). Although BCMA-targeted therapies are a major advance in such patients, none of them are curative thus far, with the median progression-free survival (PFS) ranging from 3 months in BCMA-antibody drug conjugates (ADCs) to approximately 1 year in BCMA chimeric antigen receptor T-cell (CAR T-cell) therapies. Furthermore, unique toxicities of BCMA-targeted agents such as ocular toxicity (ADCs), cytokine release syndrome, or neurotoxicity (CAR Ts and BiTEs) may preclude their use in many patients. Hence, there is a critical unmet need in patients with triple-class-refractory myeloma.The STI-6129 ADC is produced by conjugating STI-5171, a fully human anti-CD38 mAb, with a covalently bound tubulin inhibitor, duostatin 5.2 (DUO-5.2), using a proprietary linker technology with a 3:1 drug-antibody ratio. STI-6129 binds to different CD38 epitopes than daratumumab. Upon binding to CD38, STI-6129 ADC is internalized by the cancer cell and undergoes lysosomal degradation, releasing DUO-5.2. This in turn leads to G2-phase cell cycle arrest, followed by caspase 3/7-dependent apoptosis and cell death. In studies on cynomolgus monkeys, the serum level of DUO-5.2 remained undetectable at all doses except at the highest dose of 4.5 mg/kg, indicating low likelihood of off-target toxicity. In vitro studies of primary human plasma cells, human tumor models, and animal xenograft models have demonstrated target elimination of CD38-positive human plasma cells by STI-6129. Importantly, STI-6129 has demonstrated cytotoxic activity in human multiple myeloma cells isolated from daratumumab-refractory patients (Figure 1). Hence, further investigation on clinical activity of STI-6129 is warranted.Study Design: The 38-ADC-RRMM-101 study is a two-stage, multicenter, open-label, dose-finding phase 1/2 trial. The phase 1 trial is designed to identify the recommended phase 2 dose (RP2D) of STI-6129 by assessing safety, preliminary efficacy, and pharmacokinetics in patients with relapsed/refractory (RR) myeloma. The phase 2a stage of the trial will be a single-arm study to investigate the efficacy of STI-6129 in an expansion cohort of RR myeloma patients. Up to 25 patients will be enrolled in the phase 1 stage and 30 in the phase 2 stage of the study. The key inclusion criteria are the following: (a) RR myeloma with at least 3 prior lines of therapy in addition to being refractory to at least 1 PI, 1 IMiD, and 1 anti-CD 38 mAb; (b) measurable disease. The key exclusion criteria are: (a) receipt of the last dose of any anti-CD mAb within 90 days; (b) grade ≥3 neuropathy or grade 2 neuropathy with pain; (c) current history of CTCAE grade 3 muscle paresis, eyelid conditions, glaucoma, or any other ocular disorder that is CTCAE grade 2; (d) estimated creatinine clearance <60 ml/min; (e) left ventricular ejection fraction<40%. The primary endpoint of phase 1 stage of the study is safety, particularly any dose limiting toxicities. The primary endpoint of the phase 2 part of the study is overall response rate as per IMWG criteria. The dosing cohorts in the dose escalation phase will range from 0.25 mg/kg to 3.68 mg/kg. Given the potential for on-target off-tumor toxicity due to expression of CD38 on non-clonal plasma cells and other hematopoietic cells, blood counts and immunoglobulin levels will be closely monitored. While neurotoxicity or ocular toxicity were not observed with STI-6129 in animal models, including non-human primates, such event will be considered as adverse events of special interest (AESI) and comprehensive neurology and ocular (including slit lamp) examinations will be performed at baseline and study completion, and at any AESI. STI-6129 will be administered intravenously once in a 4-week cycle, with the intention being to treat patients until disease progression or unacceptable toxicity. [Display omitted] DisclosuresYan: Sorrento Therapeutics: Current Employment. Royal: Sorrento Therapeutics: Current Employment.

Downregulation of long noncoding RNA T1NCR inhibits cell proliferation, invasion, and epithelial-mesenchymal transition of hepatocellular carcinoma

Accumulating reports have identified that long non-coding RNAs (IncRNAs) function as key regulators of tumor initiation and progression. The aim of the current study was to determine the clinical significance and functional role of TINCR in hepatocellular carcinoma (HCC). In the present study, the level of IncRNA TINCR expression was significantly upregulated in HCC tissues compared to adjacent normal tissues. Higher levels of IncRNA TINCR expression were significantly correlated with tumor size and vascular invasion of HCC patients. LncRNA TINCR knockdown inhibited cell proliferation ability, increased the proportion of G1 phase cells, reduced the proportion of S phase cells, and suppressed cell invasion of HCC in vitro. Additionally, IncRNA TINCR knockdown inhibited the HCC cell epithelial-mesenchymal transition (EMT) phenomenon by upregulating E-cadherin and reducing N-cadherin expression. We demonstrated that knockdown of IncRNA reduced tumor growth in vivo. Thus, these results indicated that IncRNA TINCR exhibits a tumor oncogenic role in HCC and inhibition of IncRNA TINCR might serve as a therapeutic target for HCC.

The anti-neoplastic activities of aloperine in HeLa cervical cancer cells are associated with inhibition of the IL-6-JAK1-STAT3 feedback loop.

Cervical cancer (CC) is recognized as the most common neoplasm in the female reproductive system worldwide. The lack of chemotherapeutic agents with outstanding effectiveness and safety severely compromises the anti-cipated prognosis of patients. Aloperine (ALO) is a natural quinolizidine alkaloid with marked anti-cancer effects on multiple malignancies as well as favorable activity in relieving inflammation, allergies and infection. However, its therapeutic efficacy and underlying mechanism in CC are still unclear. In the current study, MTT assay was employed to evaluate the viability of HeLa cells exposed to ALO to preliminarily estimate the effectiveness of ALO in CC. Then, the effects of ALO on the proliferation and apoptosis of HeLa cells were further investigated by plate colony formation and flow cytometry, respectively, while the migration and invasion of ALO-treated HeLa cells were evaluated using Transwell assay. Moreover, nude mice were subcutaneously inoculated with HeLa cells to demonstrate the anti-CC properties of ALO in vivo. The molecular mechanisms underlying these effects of ALO were evaluated by Western blot and immunohistochemical analysis. This study experimentally demonstrated that ALO inhibited the proliferation of HeLa cells via G2 phase cell cycle arrest. Simultaneously, ALO promoted an increase in the percentage of apoptotic HeLa cells by increasing the Bax/Bcl-2 ratio. Additionally, the migration and invasion of HeLa cells were attenuated by ALO treatment, which was considered to result from inhibition of epithelial-to-mesenchymal transition. For molecular mechanisms, the expression and activation of the IL-6-JAK1-STAT3 feedback loop were markedly suppressed by ALO treatment. This study indicated that ALO markedly suppresses the proliferation, migration and invasion and enhances the apoptosis of HeLa cells. In addition, these prominent anti-CC properties of ALO are associated with repression of the IL-6-JAK1-STAT3 feedback loop.

Caspase-2 regulates S-phase cell cycle events to protect from DNA damage accumulation independent of apoptosis.

In addition to its classical role in apoptosis, accumulating evidence suggests that caspase-2 has non-apoptotic functions, including regulation of cell division. Loss of caspase-2 is known to increase proliferation rates but how caspase-2 is regulating this process is currently unclear. We show that caspase-2 is activated in dividing cells in G1-phase of the cell cycle. In the absence of caspase-2, cells exhibit numerous S-phase defects including delayed exit from S-phase, defects in repair of chromosomal aberrations during S-phase, and increased DNA damage following S-phase arrest. In addition, caspase-2-deficient cells have a higher frequency of stalled replication forks, decreased DNA fiber length, and impeded progression of DNA replication tracts. This indicates that caspase-2 protects from replication stress and promotes replication fork protection to maintain genomic stability. These functions are independent of the pro-apoptotic function of caspase-2 because blocking caspase-2-induced cell death had no effect on cell division, DNA damage-induced cell cycle arrest, or DNA damage. Thus, our data supports a model where caspase-2 regulates cell cycle and DNA repair events to protect from the accumulation of DNA damage independently of its pro-apoptotic function.

The modulation of PI3K/Akt pathway by 3β hydroxylup-12-en-28-oic acid isolated from Thymus linearis induces cell death in HCT-116 cells.

The presence of intricate carbon skeletons in natural compounds enhances their bioactivity spectrum with unique modes of action at several targets in various dreadful diseases like cancer. The present study was designed to purify the molecules from Thymus linearis and elucidate their antiproliferative activity. The compounds were isolated from the active methanolic extract of Thymus linearis through column chromatography and characterized by various spectroscopic techniques. Antiproliferative activity of isolated compounds was evaluated using MTT assay on cancer and normal cell lines. Mechanism of cell death was elucidated using flow cytometric, microscopic, and Western blot analysis. Four compounds, Sitosterol, Chrysin, 3β-hydroxylup-12-en-28-oic acid (3BH), and β-Sitosterol glycoside, were isolated. Among these, 3BH was most potent antiproliferative agent across all cell lines under study, HCT-116 being the most affected one. 3BH was demonstrated to downregulate PI3Ksubunits (p110α and p85α), downstream pAktSer473 and prompted G1 phase cell cycle arrest. The cell cycle CDK inhibitor p27 and p21 were upregulated with simultaneous downregulation of cyclin D1 and cyclin E in HCT-116 cells. This was accompanied by apoptosis, as depicted by decrease in Bcl-2/Bax ratio, with increase in active caspases-3 and caspase-9, cleavage of PARP-1, the generation of reactive oxygen species (ROS), and the loss of mitochondrial membrane potential. The findings established that 3BH induced cell death in HCT-116 cells by modulating PI3K/Akt signaling axis, impeding cell cycle, and instigating apoptosis.

Assessment of tantalum nanoparticle-induced MC3T3-E1 proliferation and underlying mechanisms

ObjectiveIn our previous study, tantalum nanoparticle (Ta-NPs) was demonstrated to promote osteoblast proliferation via autophagy induction, but the specific mechanism remains unclear. In the present study, we will explore the potential mechanism.MethodsTa-NPs was characterized by transmission electron microscopy, scanning electron microscopy, dynamic light scattering, and BET specific surface area test. MC3T3-E1 were treated with 0 or 20 μg/mL Ta-NPs with or without pretreatment with 10 μM LY294002, Triciribine, Rapamycin (PI3K/Akt/mTOR pathway inhibitors) for 1 h respectively. Western blotting was used to detect the expressions of pathway proteins and LC3B. CCK-8 assay was used to assess cell viability. Flow cytometry was used to detect apoptosis and cell cycle.ResultsAfter pretreatment with LY294002, Triciribine and Rapamycin, the p-Akt/Akt ratio of pathway protein in Triciribine and Rapamycin groups decreased (P < 0.05), while the autophagy protein LC3-II/LC3-I in the Rapamycin group was upregulated obviously (P < 0.001). In all pretreated groups, apoptosis was increased (LY294002 group was the most obvious), G1 phase cell cycle was arrested (Triciribine and Rapamycin groups were more obvious), and MC3T3-E1 cells were proliferated much more (P < 0.01, P < 0.001, P < 0.05).ConclusionPretreatment with Triciribine or Rapamycin has a greater effect on pathway protein Akt, cell cycle arrest, autophagy protein, and cell proliferation but with inconsistent magnitude, which may be inferred that the Akt/mTOR pathway, as well as its feedback loop, were more likely involved in these processes.

A novel stilbene derivative (GMQ3) suppressed proliferation and induced apoptosis in lung cancer via the p38-MAPK/SIRT1 pathway

BackgroundLung cancer is the primary cause of cancer-related mortality worldwide. The anticancer effect of stilbene has been noted in various tumor types. GMQ3, which has a stilbene-mimicking skeleton, is a novel small-molecule compound with promising antitumor activity. Our results revealed that GMQ3 not only suppressed cell proliferation and cell migration of lung cancer cells but also led to G1 phase cell cycle arrest and triggered caspase-dependent apoptosis. Furthermore, investigation of the molecular mechanism showed that GMQ3 could inhibited proliferation and induced apoptosis via the p38-MAPK/SIRT1 pathway both in vitro and in vivo. Xenograft tumor mouse models showed that GMQ3 significantly inhibited tumor growth in vivo without affecting body weight. Our findings indicated that GMQ3 exerts a strong anticancer action by suppressing cell proliferation, inhibiting cell migration and inducing cell apoptosis. Moreover, the efficacy of GMQ3 was enhanced in the presence of CDK4/6 inhibitor Abemaciclib. We conclude that GMQ3 is a promising agent with potential for lung cancer.

Total Phenols, Identification of Active Compounds and Anticancer Activity of Salvia judaica Boiss against the breast Cancer Cell MDA-231

Salvia judaica is an annual herb from genus Salvia L.; the largest genera of Lamiaceae. It’s a medicinal plant prominent in pharmaceutical applications in many countries around the world. This study aimed to explore bioactive compounds likely to be responsible for the plant anticancer activity, and evaluate anticancer effects, after determining the total content of phenols in the ethanol extract and essential oil in this species. Ethanol extract (EE) and essential oil (EO) were prepared from dried aerial parts (leaves and the flower). GC-MS analysis of EO showed the presence of/43/ effective compounds in varying proportions, the major compounds were sesquiterpenes like delta-cadinene, alpha-Gurjunene, beta-humulene, and alpha-caryophyllene. This is the first study revealed that S.judaica is so rich in phenols which proceeded S.officinalis, noting the superiority of the EE over the EO samples in the total phenols. Anticancer properties of EE and EO of S. judaica against MDA-231 breast cancer cell line were studied -for the first time - by cell cycle analysis and Annexin V/PI apoptosis assay using Flow cytometry technique. Cells were treated with EE (0.001, 0.01, 0.02, 0.1mg/ml) and EO (0.005, 0.01, 0.02, 0.03, 0.04 mg/ml) at various concentrations for48 h. The results revealed that both EE and EO induced cell cycle arrest at G1-phase. Cells treated with EE and EO for 48h showed increasing the percentage of cells in G1-phase and decreasing the percentage of cells in S-phase with increasing concentration compared with untreated cells (control). Annexin V-FITC/PI assay confirmed that EO and EE were able to induce apoptosis. Cells treated with EOat (0.04 mg/ml) for 48h resulted in apoptotic cells at 96.68%, and necrotic cells at 0.12%, compared with untreated cells. On the other hand, Cells treated with EE at (0.1 mg/ml) for 48h resulted in apoptotic cells at 94.43%, and necrotic cells at 0.47%, compared with control. Results revealed that EO is better than EE as anticancer; treatment with EO resulted in more apoptotic cells and less necrotic cells, and there were significant differences between them. This confirmed that EO contains specific anticancer compounds as showed by GC-MS analysis. However, more studies should be performed to explore antioxidants present in S.judaica and determine the underlying mechanism of their anti-breast cancer properties.

Oncogenic KRAS drives radioresistance through upregulation of NRF2-53BP1-mediated non-homologous end-joining repair

KRAS-activating mutations are oncogenic drivers and are correlated with radioresistance of multiple cancers, including colorectal cancer, but the underlying precise molecular mechanisms remain elusive. Herein we model the radiosensitivity of isogenic HCT116 and SW48 colorectal cancer cell lines bearing wild-type or various mutant KRAS isoforms. We demonstrate that KRAS mutations indeed lead to radioresistance accompanied by reduced radiotherapy-induced mitotic catastrophe and an accelerated release from G2/M arrest. Moreover, KRAS mutations result in increased DNA damage response and upregulation of 53BP1 with associated increased non-homologous end-joining (NHEJ) repair. Remarkably, KRAS mutations lead to activation of NRF2 antioxidant signaling to increase 53BP1 gene transcription. Furthermore, genetic silencing or pharmacological inhibition of KRAS, NRF2 or 53BP1 attenuates KRAS mutation-induced radioresistance, especially in G1 phase cells. These findings reveal an important role for a KRAS-induced NRF2-53BP1 axis in the DNA repair and survival of KRAS-mutant tumor cells after radiotherapy, and indicate that targeting NRF2, 53BP1 or NHEJ may represent novel strategies to selectively abrogate KRAS mutation-mediated radioresistance.

PCNA inhibition enhances the cytotoxicity of β-lapachone in NQO1-Positive cancer cells by augmentation of oxidative stress-induced DNA damage.

β-Lapachone is a classic quinone-containing antitumor NQO1-bioactivatable drug that directly kills NQO1-overexpressing cancer cells. However, the clinical applications of β-lapachone are primarily limited by its high toxicity and modest lethality. To overcome this side effect and expand the therapeutic utility of β-lapachone, we demonstrate the effects of a novel combination therapy including β-lapachone and the proliferating cell nuclear antigen (PCNA) inhibitor T2 amino alcohol (T2AA) on various NQO1+ cancer cells. PCNA has DNA clamp processivity activity mediated by encircling double-stranded DNA to recruit proteins involved in DNA replication and DNA repair. In this study, we found that compared to monotherapy, a nontoxic dose of the T2AA synergized with a sublethal dose of β-lapachone in an NQO1-dependent manner and that combination therapy prevented DNA repair, increased double-strand break (DSB) formation and promoted programmed necrosis and G1 phase cell cycle arrest. We further determined that combination therapy enhanced antitumor efficacy and prolonged survival in Lewis lung carcinoma (LLC) xenografts model. Our findings show novel evidence for a new therapeutic approach that combines of β-lapachone treatment with PCNA inhibition that is highly effective in treating NQO1+ solid tumor cells.

Atractylodin may induce ferroptosis of human hepatocellular carcinoma cells.

BackgroundIt has been reported that atractylodin has a potential antitumor effect. This study aimed to investigate the effects of atractylodin on Huh7 and Hccm hepatocellular carcinoma (HCC) cells and its molecular mechanism.MethodsHuh7 and Hccm cells were cultured in vitro, and their viability was detected by CCK-8 assay and the half inhibitory concentration (IC50) was calculated. The cells were treated with different concentrations of atractylodin, and the migration and invasion ability of cells was detected by scratch assay and Transwell assay. The cell cycle change and apoptosis rate were detected by flow cytometry. IlluminaHiSeq4000 platform was used for transcriptome sequencing, and the results were analyzed for gene differential expression, gene function, and signal pathway enrichment. Morphological changes of cells were detected by transmission electron microscopy, reactive oxygen species (ROS) levels were detected by DCFH-DA probe, and the expressions of ferroptosis related proteins GPX4, ACSL4, FTL, and TFR1 were detected by Western blot.ResultsThe results showed that atractylodin could inhibit the proliferation, migration, and invasion of Huh7 and Hccm cells, regulate the cell cycle, and induce cell apoptosis and G1 phase cell cycle arrest. In addition, it could significantly induce the increase of intracellular ROS levels, decrease the expression of GPX4 and FTL proteins, and up-regulate the expression of ACSL4 and TFR1 proteins.ConclusionsAtractylodin can inhibit the proliferation, migration, and invasion of Huh7 and Hccm liver cancer cells, and induce cell apoptosis and cell cycle arrest. In addition, our results suggest that atractylodin may induce ferroptosis in HCC cells by inhibiting the expression of GPX4 and FTL proteins, and up-regulating the expression of ACSL4 and TFR1 proteins.

Design, synthesis and evaluation of new quinazolin-4-one derivatives as apoptotic enhancers and autophagy inhibitors with potent antitumor activity.

This work presents the design and synthesis of a series of new quinazolin-4-one derivatives, based on the established effectiveness of quinazoline-based small molecules as anticancer agents. Synthesized compounds were more potent against MCF-7 than A-549 with low to submicromolar IC50s. Compound 17 exhibited the best IC50 being equipotent with the positive control doxorubicin (IC50= 0.06μM) and better than 5-fluorouracil (IC50= 2.13μM). Compound 17 was further tested against MDA-MB-231 and MCF-10A and was found to be>2 folds more cytotoxic on MCF-7. Significant apoptotic activity was elicited by 17 on MCF-7 where it increased apoptotic cell death along with induction of pre-G1 and G1-phase cell cycle arrest. Similarly, 17 was able to induce apoptosis in MD-MB-231 treated cells associated with a disruption of the cell cycle causing arrest at the pre-G1 and S phases. Investigation of gene expression in MCF-7 demonstrated an increased expression of the proapoptotic genes P53, PUMA, Bax, caspases 3, 8 and 9 and a decrease of the anti-apoptotic gene Bcl2. Also, 17 reduced autophagy giving way for apoptosis to induce cancer cells death. This latter observation was associated with downregulation of EGFR and its downstream effectors PI3K, AKT and mTor. As its biomolecular target, 17 also inhibited EGFR similar to erlotinib (IC50=0.072 and 0.087μM, respectively). Additionally, invivo testing in a mouse model of breast cancer affirmed the anti-tumor efficacy of 17. Finally, docking of 17 against EGFR ATP binding site demonstrated its ability to bind with EGFR resembling erlotinib.

TOB1 modulates the decidualization of human endometrial stromal cells via the Notch pathway.

Decidualization is critical for embryo implantation and the success of pregnancy; however, the mechanisms underlying this process remain largely unknown. In the present study, RNA sequencing was used to detect the expression levels of transducer of ERBB2/1(TOB1) in endometrial samples derived from proliferative and secretory phases. A decidualization model was induced using the combination of estrogen (E2) and progestin (P4) in human endometrial stromal cells (HESCs). The cell counting kit-8 assay was used to detect the viability of HESCs. Related proteins were detected by qPCR and western blot. The results indicated that TOB1 expression was upregulated in the secretory endometrial samples compared with the corresponding expression observed in the proliferative samples. The expression levels of TOB1 and Notch1 were markedly increased in E2P4-treated HESCs compared with those in the control cells. Treatment with E2P4 strongly suppressed the proliferation of HESCs and induced a G1-phase cell cycle arrest. These effects were abolished by knockdown of TOB1 or treatment with of the cells with the Notch inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butyl ester. Therefore, these findings highlighted an important role for TOB1/Notch signaling in E2P4-induced decidualization in HESCs, which may provide novel targets for improving the endometrial receptivity.