Volume Of Xenografts Research Articles

The Effective Analysis for Blue Honeysuckle Extract in the Treatment of Hepatocellular Carcinoma.

To further determine how BHE affected the growth of HCC cells, the proportion of each cell cycle phase was explored in HCC cells by flow cytometry. Blue honeysuckle (Lonicera caerulea L.) is a species of bush that grows in eastern Russia. Blue honeysuckle extract (BHE) is rich in bioactive phytochemicals which can inhibit the proliferation of tumor cells. The mechanism underlying the anticancer activity of BHE in primary liver cancer is poorly understood. The purpose of this study was to evaluate the growth inhibition mechanism of bioactive substances from blue honeysuckle on hepatocellular carcinoma (HCC) cells and to explore its protein and gene targets. The compounds in BHE were determined by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). Cell counting kit-8 (CCK8) assay was used to evaluate the effects of BHE on HCC cell proliferation, and flow cytometry assay (FCA) was used to determine how BHE arrested the proportion of each cell cycle phase in HCC cells. Western blot (WB) was performed to determine the expression of cell cycle-related proteins in HCC cells treated with different concentrations of BHE. The xenograft tumor animal models were established by HCC cell implantation. The results showed that cyanidin-3-o-glucoside and cyanidin-3-o-sophoroside which are the main biologically active components were detected in BHE. BHE is highly effective in inhibiting the proliferation of HCC cells by arresting the HCC cell cycle in the G2/M phase. BHE also downregulated the expression of conventional or classical dendritic cells-2 (cDC2) and cyclin B1 by promoting the expression of myelin transcription factor 1 (MyT1) in HCC cells. The weight and volume of xenografts were significantly decreased in the BHE treated groups when compared to the control group. BHE increased the expression of MyT1 in xenograft tissues. These findings showed that blue honeysuckle extract inhibits proliferation in vivo and in vitro by downregulating the expression of cDC2 and cyclin B1 and upregulating the expression of MyT1 in HCC cells.

STAT3-mediated upregulation of LINC00520 contributed to temozolomide chemoresistance in glioblastoma by interacting with RNA-binding protein LIN28B

A considerable number of glioblastoma (GBM) patients developed drug resistance to Temozolomide (TMZ) during chemotherapy, resulting in therapeutic failure and tumor recurrence. However, the exact mechanism of TMZ chemoresistance in GBM is still poorly clarified. As a novel identified lncRNA, LINC00520 was located on chromosome 14 and overexpressed in multiple human cancers. This study was designed and conducted to investigate the role and underlying mechanism of LINC00520 in GBM chemoresistance to TMZ. The qRT-PCR assay demonstrated that LINC00520 was significantly overexpressed in TMZ-sensitive and/or TMZ-resistant GBM cells (P < 0.001). The silencing of LINC00520 markedly reduced the cell viability, suppressed colony formation, induced cell apoptosis and G1/S phase arrest in TMZ-resistant cells (P < 0.001). In contrast, overexpression of LINC00520 conferred TMZ-resistant phenotype of GBM cells in vitro (P < 0.001). The orthotopic xenograft model was established and the results indicated that the volume of tumor xenografts in vivo was markedly inhibited by TMZ treatment after the silencing of LINC00520 (P < 0.001). Luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay revealed a strong affinity of transcription factor STAT3 to the promoter regions of LINC00520, suggesting that STAT3 mediated the aberrant expression of LINC00520 in GBM. Further experiments demonstrated that LINC00520 could interact with RNA-binding protein LIN28B to inhibit autophagy and reduce DNA damage, thereby contributing to TMZ chemoresistance in GBM. These findings suggested that STAT3/LINC00520/LIN28B axis might be a promising target to improve TMZ chemoresistance of GBM.

Forkhead Box S1 mediates epithelial-mesenchymal transition through the Wnt/β-catenin signaling pathway to regulate colorectal cancer progression

BackgroundRecent studies have shown that the fox family plays a vital role in tumorigenesis and progression. Forkhead Box S1 (FOXS1), as a newly identified subfamily of the FOX family, is overexpressed in certain types of malignant tumors and closely associated with patient's prognosis. However, the role and mechanism of the FOXS1 in colorectal cancer (CRC) remain unclear.MethodFOXS1 level in CRC tissues and cell lines was analyzed by western blot and quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemistry (IHC) was used to detect the relationship between FOXS1 expression and clinicopathological features in 136 patients in our unit. The expression of FOXS1 was knocked down in CRC cells using small interfering RNA (siRNA) technology. Cell proliferation was assessed by CCK8 assay, colony formation, and 5-Ethynyl-20-deoxyuridine (EdU) incorporation assay. Flow cytometry detected apoptosis and wound healing, and Transwell assays determined cell migration and invasion. Western blotting was used to detect the levels of proteins associated with the Wnt/β-catenin signaling pathway. Then, we used short hairpin RNA (shRNA) to knock down FOXS1 to see the effect of FOXS1 on the proliferation, migration, invasion, and metastasis of CRC cells in vivo. Finally, we investigated the impact of Wnt activator LiCl on the proliferation, migration, invasion, and metastasis of CRC cells after FOXS1 knockdown.ResultCompared to those in normal groups, FOXS1 overexpressed in CRC tissues and CRC cells (P < 0.05). Upregulation of FOXS1 association with poor prognosis of CRC patients. si-FOXS1 induced apoptosis and inhibited proliferation, migration, invasion, the epithelial-mesenchymal transition (EMT), and the Wnt/β-catenin signaling pathway in vitro; sh-FOXS1 inhibited the volume and weight of subcutaneous xenografts and the number of lung metastases in vivo. LiCl, an activator of Wnt signaling, partially reversed the effect of FOXS1 overexpression on CRC cells.ConclusionFOXS1 could function as an oncogene and promote CRC cell proliferation, migration, invasion and metastasis through the Wnt/βcatenin signaling pathway, FOXS1 may be a potential target for CRC treatment.

Assessment of antitumor effect of 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone in subcutaneous xenografts of A-549 tumor cell culture.

e20520 Background: The aim of the study was an assessment of antitumor effect of 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone for subcutaneous xenografts of A-549 lung tumor cells in immunodeficient Balb/c Nude mice. Methods: 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone is a new compound in the series of 2-quinoline-2-yl-1,3-tropolone derivatives. The study included 50 immunodeficient Balb/c Nude mice divided into 5 groups depending on the dosage of the studied substance (0.0055; 0.055; 0.55 and 2.75 mg/g). The A-549 cells of lung cancer were used as the xenograft. Antitumor effect of tropolone was evaluated by the inhibition of tumor growth (ITG%) and the index of tumor growth (I). The experiment lasted for 36 days starting from the first administration of substances. Results: Indicators of the average tumor volume on day 36 of the experiment in experimental groups 1, 2, 3 and 4 and in the control group were 678.9; 952.3; 1746.4; 2150.8 and 2729.5 mm3, respectively. The indices of tumor growth in groups 1, 2, 3 and 4 were statistically significantly lower than in group 5 (controls) starting from days 15, 21, 21 and 24, respectively, and until the end of the experiment. Maximal differences between groups 1 and 5 were observed on days 33 and 36 – by 3.7 (p = 0.01) and 4.1 (p = 0.003) times, respectively. Antitumor effect of 2-(6,8-dimethyl-5-nitro-4-chloroquinoline-2-yl)-5,6,7-trichloro-1,3-tropolone demonstrated by the study could be associated with various mechanisms. For example, its closely related compound – hinoktiol, according to numerous studies, has a cytotoxic effect associated with stopping the cell cycle, induction of apoptosis, DNA damage, and autophagic death of tumor cells. Conclusions: The study demonstrated statistically significant differences in xenograft volumes between all experimental groups and the control group. 2.75 mg/g of mouse weight was the most effective dosage of the studied compound leading to a slow decrease in tumor growth rates and a decrease in the volumes of subcutaneous xenografts.

KDM2B mediates the Wnt/β-catenin pathway through transcriptional activation of PKMYT1 via microRNA-let-7b-5p/EZH2 to affect the development of non-small cell lung cancer

The significance of KDM2B in oncogenesis has been appreciated, but the mechanism behind is incompletely understood. In this work, we addressed its effects on the progression of non-small cell lung cancer (NSCLC). Overexpression of KDM2B was linked to dismal prognoses of NSCLC patients. Based on the expression levels of KDM2B in a panel of NSCLC cell lines, A549, showing lower level of expression, and SK-MES-1, showing higher levels of expression, were selected as model systems to evaluate the effect of KDM2B overexpression and KDM2B silencing, respectively. Knockdown of KDM2B hampered NSCLC cell proliferation, invasion, as well as migration, while enhanced apoptosis. Additionally, KDM2B repressed the expression of microRNA (miR)-let-7b-5p through demethylation modification of H3K36me2, thereby promoting the expression of zester homolog 2 (EZH2), the target gene of let-7b-5p in NSCLC. Moreover, EZH2 transcriptionally induced the expression of PKMYT1 to activate the Wnt/β-catenin pathway. Sh-EZH2 and sh-PKMYT1 neutralized the supporting effects of KDM2B on cell proliferation, invasion and migration. Additionally, deletion of KDM2B reduced the xenograft volumes in nude mice. In conclusion, KDM2B induces the EZH2/PKMYT1/Wnt/β-catenin axis by inhibiting the let-7b-5p expression, which promotes NSCLC growth. More investigations are essential to determine the oncogenic role of KDM2B in NSCLC.

Xihuang pills induce apoptosis in hepatocellular carcinoma by suppressing phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin pathway.

BACKGROUNDThe phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin (PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills (XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma (HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHP-associated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway.AIMTo confirm the effect of XHP on HCC and the possible mechanisms involved.METHODSThe chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS). Cell-based experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP (0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay. Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction (RT-qPCR), respectively. Third, Western blotting and RT–qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway. Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed.RESULTSThe following 12 compounds were identified in XHP using high-resolution mass spectrometry: Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-β-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-β-boswellic acid, 5β-androstane-3,17-dione, and 3-acetyl-11-keto-β-boswellic acid. The cell viability assay results showed that treatment with 0.625 mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose- and time-dependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract (0.625 mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins (e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights.CONCLUSIONXHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3. Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.

Mitochondrial protein LETM1 and its-mediated CTMP are potential therapeutic targets for endometrial cancer.

Leucine zipper/EF hand-containing transmembrane-1 (LETM1) is an important mitochondrial protein, while its function in endometrial cancer remains unknown. This study aimed to explore the function of LETM1 in endometrial cancer and reveal the underlying mechanisms involving carboxy-terminal modulator protein (CTMP). Immunohistochemistry was performed to detect the expression of LETM1 and CTMP in normal, atypical hyperplastic and endometrial cancer endometrial tissues. LETM1 and CTMP were silenced in two endometrial cancer cell lines (ISK and KLE), which were verified by western blot. Cell viability, colony number, migration and invasion were detected by cell counting kit-8, colony formation, wound healing and trans-well assays, respectively. A xenograft mouse model was established to determine the antitumor potential of LETM1/CTMP silencing in vivo . In addition, CTMP was overexpressed to evaluate its regulatory relationship with LETM1 in endometrial cancer cells. The expression of LETM1 and CTMP proteins were higher in endometrial cancer tissues than atypical hyperplastic tissues and were higher in atypical hyperplastic tissues than normal tissues. LETM1 and CTMP were also upregulated in ISK and KLE cells. Silencing of LETM1 or CTMP could decrease the viability, colony number, migration and invasion of endometrial cancer cells and the weight and volume of tumor xenografts. In addition, CTMP was downregulated by LETM1 silencing in KLE cells, and its overexpression enhanced the malignant characteristics of si-LETM1-transfected KLE cells. Silencing of LETM1 inhibits the malignant progression of endometrial cancer through downregulating CTMP.

Combined use of 177 Lu-DOTATATE peptide receptor radionuclide therapy and fluzoparib for treatment of well-differentiated neuroendocrine tumors: A preclinical study.

Peptide receptor radionuclide therapy (177 Lu-DOTATATE) causes DNA strand breaks and has been validated for well-differentiated neuroendocrine tumor treatment. Poly-(ADP-ribose)-polymerase inhibitors have also been used for malignant tumors with deficient DNA repair. We aimed to determine whether the poly-(ADP-ribose)-polymerase inhibitor fluzoparib could enhance the anti-tumor effects of 177 Lu-DOTATATE in neuroendocrine tumor cells and xenografts. The neuroendocrine characteristics of NCI-H727 bronchial carcinoid cells were evaluated by immunofluorescence staining. The synergistic effects of fluzoparib and 177 Lu-DOTATATE were evaluated by cell proliferation and flow cytometry assays. Tumor response and the side effects of combination therapy were also assessed in xenograft mice treated with 77 Lu-DOTATATE and fluzoparib alone or in combination. Somatostatin receptors were specifically expressed in NCI-H727 cells and tumor xenografts. 177 Lu-DOTATATE (22.20MBqmL-1 ) and fluzoparib (50µm) inhibited cell proliferation by 16.6% and 35.6%, respectively, compared to 73.2% in cells treated with their combination. Tumor cell proliferation was significantly suppressed by 177 Lu-DOTATATE (22.20MBqmL-1 , 4.4-fold) and fluzoparib (50µm, 2.1-fold). 177 Lu-DOTATATE caused cell cycle arrest mainly at G1 phase, whereas fluzoparib caused arrest at G2/M phase, and combined treatment with both agents caused cell cycle arrest at G1 phase, similar to 177 Lu-DOTATATE alone. The volume of tumor xenografts was reduced by 18.6% in mice receiving combined treatment, compared to 4.9% and 11.4% in mice treated with 177 Lu-DOTATATE or fluzoparib alone. Fluzoparib can potentiate the anti-tumor effect of 177 Lu-DOTATATE in NCI-H727 cells in a synergistic manner by arresting the cell cycle at G1 phase. Further preclinical and clinical studies are warranted to validate these findings.

Iron oxide nanoparticles loaded with paclitaxel inhibits glioblastoma by enhancing autophagy-dependent ferroptosis pathway

ObjectiveTo explore inhibitory effect of iron oxide nanoparticles loaded with paclitaxel (IONP@PTX) on glioblastoma (GBM) and its potential mechanism. MethodsIONP@PTX was synthesized and the characteristics were assessed by chemico-physical analysis and observed directly under transmission electron microscope. U251 cells and HMC3 cells were separately incubated with IONP@PTX and PTX, and then cell viability was detected by Cell Counting Kit-8. The capacity of cell invasive and migration was verified by Scratch wound healing and Transwell migration and invasion assays. Expressions levels of autophagy and ferroptosis biomarkers were demonstrated by Western blotting assay. Intracellular reactive oxygen species (ROS) and lipid peroxidation were detected with DCFH-DA and C11-BODIPY staining, respectively. Intracellular concentration of iron ions was quantified spectrophotometrically. Moreover, inhibitory effect of IONP@PTX on GBM was evaluated by monitoring tumor growth and the toxicity of IONP@PTX was evaluated by measuring the body weight and index of liver and spleen in the mice bearing GBM xenograft. ResultsThe successfully synthesized IONP@PTX possesses a hydrate diameter about 36 nm and a core diameter around 10 nm. IONP@PTX exerted an inhibitory effect on U251 cells, but had little effect on HMC3 cells compared with PTX alone. In addition, IONP@PTX inhibited the capacity of cell migration and invasion, increased the levels of iron ions, ROS and lipid peroxidation, enhanced the expression of autophagy-related protein Beclin1 and LC3II, and suppressed the expression of p62 and ferroptosis-related protein GPX4 in vitro compared with control group. Moreover, administration of IONP@PTX suppressed tumor volume of GBM xenografts and decreased the expression level of GPX4 protein in tumor tissues in comparison with control group (All P < 0.05). Intriguingly, the effect of IONP@PTX on GBM could be weakened by additional 3-MA or enhanced by additional rapamycin in vitro and in vivo (P < 0.05). More importantly, IONP@PTX had no obvious toxic effect on mice bearing GBM xenograft. ConclusionIONP@PTX inhibits GBM growth by enhancing autophagy-dependent ferroptosis pathway, thus it might become a potential ferroptosis-inducing agent for ferroptosis-based tumor therapy.

Niuhuang (Bovis Calculus)-Shexiang (Moschus) combination induces apoptosis and inhibits proliferation in hepatocellular carcinoma via PI3K/AKT/mTOR pathway

ObjectiveTo investigate the effects of Niuhuang (Bovis Calculus, BC) and Shexiang (Moschus) (BC-Moschus) on human hepatocellular carcinoma (HCC) cells SMMC-7721 and a nude mouse model of subcutaneous xenografts, and to explore its anti-HCC mechanism. MethodsThe BC-Moschus combination was applied to two liver cancer models in vivo and in vitro. SMMC-7721 was divided into the BC-Moschus group and the control group, and different doses (rude drug dosage 0.625, 1.25, 2.5, and 5 mg/mL) of BC-Moschus extract were used for the intervention. The proliferation ability of HCC cells was detected using the Cell Counting Kit-8 (CCK-8) assay, and the migration ability was detected by a wound healing assay. A subcutaneous xenograft model was prepared using nude mice with human HCC. Specific pathogen-free-grade BALB/c nude mice (5-week-old) were randomly divided into the following groups (n = 6 per group): control (0.9% physiological saline 0.2 mL/d), BC-Moschus [BC 45.5 mg/(kg·d)+ Moschus 13 mg/(kg·d)], and cisplatin (DDP, intraperitoneal injection 5 mg/kg per week) groups. All groups were administered for 14 d. The volume and mass of the subcutaneous xenografts in nude mice were observed. The expression levels of phosphatidylinositol-3 kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway, apoptosis-associated factor p70 S6 Kinase (S6K), Bax, Bcl-2, caspase-3, and caspase-9 in nude mice subcutaneous xenografts were measured by real-time quantitative PCR (RT-qPCR) and Western blot. Terminal Deoxynucleotidy Transferase-Mediated dUTP Nick-End Labeling (TUNEL) was used for quantitative analysis of apoptotic cells. ResultsThe CCK-8 assay demonstrated that the BC-Moschus combination inhibited HCC cell proliferation in a superior manner to the use of BC and Moschus alone, and the inhibition effect was dose- and time-dependent (P < 0.01). The wound healing assay showed that the BC-Moschus combination inhibited HCC cell migration (P < 0.01). In the subcutaneous xenograft model of nude mice with human HCC, we found that the tumor volume and weight of the BC-Moschus group were lower than those of the control group (P < 0.01). The levels of the PI3K/AKT/mTOR signaling pathway and S6K protein in the BC-Moschus and DDP groups were significantly decreased (P < 0.01). The expression level of the anti-apoptotic gene Bcl-2 was downregulated (P < 0.05), and the expression of the pro-apoptotic gene Bax and apoptosis-related factors caspase-3 and caspase-9 were significantly upregulated (P < 0.01). The TUNEL assays further confirmed that the combination of the BC-Moschuas could promote HCC (P < 0.01). ConclusionThe BC-Moschus combination inhibited the proliferation and migration ability of HCC cells SMMC-7721 and effectively inhibited the growth of subcutaneous xenografts in nude mice. The mechanism may be closely related to the downregulation of the PI3K/AKT/mTOR pathway, regulation of apoptosis-related protein caspase-3, caspase-9, Bcl-2, and Bax expression, and promotion of apoptosis.

Design, Synthesis, and Biological Evaluation of the First Inhibitors of Oncogenic CHD1L.

Chromodomain helicase DNA-binding protein 1 like (CHD1L) is an oncogene implicated in tumor progression, multidrug resistance, and metastasis in many types of cancer. In this article, we described the optimization of the first lead CHD1L inhibitors (CHD1Li) through drug design and medicinal chemistry. More than 30 CHD1Li were synthesized and evaluated using a variety of colorectal cancer (CRC) tumor organoid models and functional assays. The results led to the prioritization of six lead CHD1Li analogues with improved potency, antitumor activity, and drug-like properties including metabolic stability and in vivo pharmacokinetics. Furthermore, lead CHD1Li 6.11 proved to be an orally bioavailable antitumor agent, significantly reducing the tumor volume of CRC xenografts generated from isolated quasi mesenchymal cells (M-phenotype), which possess enhanced tumorigenic properties. In conclusion, we reported the optimization of first-in-class inhibitors of oncogenic CHD1L as a novel therapeutic strategy with potential for the treatment of cancer.

Piperlongumine synergistically enhances the antitumour activity of sorafenib by mediating ROS-AMPK activation and targeting CPSF7 in liver cancer

Sorafenib, a multikinase inhibitor, is the first-line agent for advanced liver cancer. Sorafenib strongly inhibits both cell proliferation and tumour angiogenesis. However, the development of drug resistance hampers its anticancer efficacy. To improve the antitumour activity of sorafenib, we demonstrate that piperlongumine (PL), an alkaloid isolated from the fruits and roots of Piper longum L., enhances the cytotoxicity of sorafenib in HCCLM3 and SMMC7721 cells using the cell counting kit-8 test. Flow cytometry analysis indicated that PL and sorafenib cotreatment induced robust reactive oxygen species (ROS) generation and mitochondrial dysfunction, thereby increasing the number of apoptotic cells and the ratio of G2/M phase cells in both HCCLM3 and SMMC7721 cells. Furthermore, AMP-protein kinase (AMPK) signalling was activated by excess ROS accumulation and mediated growth inhibition in response to PL and sorafenib cotreatment. RNA-sequencing analysis indicated that PL treatment disrupted RNA processing in HCCLM3 cells. In particular, PL treatment decreased the expression of cleavage and polyadenylation specificity factor 7 (CPSF7), a subunit of cleavage factor I, in a time- and concentration-dependent manner in HCCLM3 and SMMC7721 cells. CPSF7 knockdown using a gene interference strategy promoted growth inhibition of PL or sorafenib monotherapy, whereas CPSF7 overexpression alleviated the cytotoxicity of sorafenib in cultured liver cancer cells. Finally, PL and sorafenib coadministration significantly reduced the weight and volume of HCCLM3 cell xenografts in vivo. Taken together, our data indicate that PL displays potential synergistic antitumour activity in combination with sorafenib in liver cancer.

Inhibition of growth of colorectal cancer patient-derived subcutaneous xenografts using combined Wnt signaling pathway inhibitor and 5‑fluorouracil

Purpose of the study. Was to analyze antitumor efficacy of the XAV 939 Wnt signaling pathway inhibitor and its combination with 5 fluorouracil in subcutaneous xenografts derived from patients with colorectal cancer.Materials and methods. Antitumor efficacy of the agents and their combination was studied in xenografts derived from patients with colorectal cancer and subcutaneously implanted in immunodeficient Balb/c Nude mice. All animals with tumors were divided into 4 groups (n = 5): group 1 received 5 fluorouracil 25 mg/kg, group 2 – XAV 939 25 mg/kg, group 3–5 fluorouracil and XAV 939 combination at the same dosages, group 4 was control. Criteria for the efficacy of the tested agents and their combination included tumor growth rate and tumor growth inhibition rate (TGI %).Results. The mean volumes of xenografts and tumor growth rate in the group receiving a combination of 5 fluorouracil and XAV 939 were 335.2 ± 40.7 mm3 , being lower than the averages of xenografts in controls – 609.3 ± 69.5 mm3 (p &lt; 0.05). The mean volumes of xenografts in the group receiving 5 fluorouracil monotherapy were 601.9 ± 45.5 mm3 , in the group with the XAV 939 monotherapy – 527.9 ± 258.6 mm3 . The highest TGI (44.99 %) was registered in the group receiving a combination of 5 fluorouracil and XAV 939.Conclusion. The study revealed the ability of combined XAV 939 Wnt signaling pathway inhibitor and 5 fluorouracil to inhibit the growth of subcutaneous xenografts derived from patients with colorectal cancer.

PROX1, a Key Mediator of the Anti-Proliferative Effect of Rapamycin on Hepatocellular Carcinoma Cells.

The MTOR signal is known to be activated in various cancer cells including hepatocellular carcinoma (HCC) cells. Rapamycin, a specific inhibitor of MTOR, has been widely used as an immunosuppressant in organ transplant patients, and its clinical application has been recently expanded to cancer therapy. In this study, the anti-proliferative effect of rapamycin was investigated in four different HCC cell lines. Rapamycin effectively inhibited the proliferation of Huh7 or Hep3B, but not that of HepG2 or SNU3160 cells. Interestingly, rapamycin increased Prospero-related homeobox 1 (PROX1) expression at the protein level, but did not affect its transcript in Huh7 as well as Hep3B cells. Moreover, immunoprecipitation assays showed that PROX1 ubiquitination was downregulated by rapamycin. Furthermore, PROX1 over-expression or siRNA knock-down in Huh7 and Hep3B cells reduced or increased proliferation, respectively. The effect of PROX1 over-expression on the sensitivity to rapamycin was not synergistic, but the effect of MTOR inhibition on cell proliferation was diminished by PROX1 siRNA. Finally, Huh7 cells were inoculated into the flanks of nude mice and rapamycin was injected daily for 14 days. The xenograft volume was decreased and PROX1 expression was increased by rapamycin. These results indicate that PROX1 plays a key role in the anti-proliferative effect of rapamycin and suggest that the increased PROX1 by MTOR inhibition can be used as a useful marker for predicting whether HCC cells can be affected by rapamycin.

Traditional Chinese medicine formula T33 inhibits the proliferation of human colorectal cancer cells by inducing autophagy.

Colorectal cancer (CRC) is a leading cause of cancer‐related death globally. Although surgery is still the major method for CRC therapy, the adoption of alternative treatments, such as traditional Chinese medicine (TCM), for CRC treatment is increasing. Our previous study has indicated the anti‐breast cancer activity of T33 (a TCM formula). Interestingly, a major ingredient in T33, Baishao (Paeoniae Radix Alba), was reported to have antiproliferative effects on CRC cells. Therefore, this study further validated the influences of T33 on HT‐29 and Caco2 cells both in vitro and in vivo. Viability and migration assays were performed to analyze the influences of T33 on proliferation and migratory activity of HT‐29 and Caco2 cells. Immunofluorescence (IF) staining and immunoblotting were performed to confirm T33‐induced autophagy in HT‐29 and Caco2 cells. Xenograft HT‐29 tumors were generated to test the effects of T33 in vivo. Significantly reduced survival and migratory activity were observed in both HT‐29 and Caco2 cells treated with T33 along with apparently increased LC3‐II protein. Significantly decreased p62/SQSTM1 protein, increased LC3‐II/LC3‐I ratio, and elevated amounts of Atg7, Atg5, and Beclin‐1 proteins were detected in both HT‐29 and Caco2 cells treated with T33. Moreover, the volume of xenograft HT‐29 tumors was significantly lower in mice receiving 200 or 600 mg/kg T33 than in control‐treated mice. These findings indicate that T33 exerts anti‐CRC activity by inducing autophagy and suggest the potential of T33 for CRC treatment.

CircFOXM1 promotes proliferation and metastasis of hepatocellular carcinoma via regulating miR-1179/SPAG5 axis

Hepatocellular carcinoma (HCC) predominantly occurs in patients with chronic liver disease, accounting for 70–90% of all liver cancer cases. The role of circFOXM1/miR-1179/SPAG5 axis in HCC has not been reported. This study aimed to explore the regulatory mechanism of circFOXM1 in HCC proliferation and metastasis. RNA polymerase inhibitor actinomycin D and RNase R exonuclease were used to identify circFOXM1 in HCC cells. The qRT-PCR was used to detect circFOXM1 expression. Specific siRNA for circFOXM1 was designed, and the sequence of circFOXM1 was inserted in pLCDH-ciR to overexpress circFOXM. Cell proliferation was detected by CCK8 in vitro, by tumor volume and tumor weight of HCC xenograft in vivo. Cell migration was detected by transwell test. Binding status of circFOXM1 with miR-1179 was detected by luciferase reporter gene assay. Rescue experiments were applied to identify the oncogenic mechanism of circFOXM1 in HCC cells. Actinomycin D assay confirmed the cyclization of circFOXM1. RNase R treatment showed that circFOXM1 was not affected by RNase R exonuclease. CCK8 assay, tumor volume and tumor weight showed that circFOXM1 effectively promoted HCC cell proliferation. Transwell assay showed that circFOXM effectively promoted migration and invasion abilities of HCC cells. Luciferase reporter gene activity assay showed that miR-1179 had complementary binding sites with circFOXM1 and SPAG5. CircFOXM1 silencing inhibited malignant phenotypes in HCC cells were partly rescued by either miR-1179 silencing or SPAG5 overexpression. CircFOXM1 promoted HCC cell proliferation and metastasis by regulating miR-1179/SPAG5 axis.

Co-Treatment with the Epigenetic Drug, 3-Deazaneplanocin A (DZNep) and Cisplatin after DZNep Priming Enhances the Response to Platinum-Based Therapy in Chondrosarcomas.

Simple SummaryChondrosarcoma is a rare bone tumor characterized by the secretion of a cartilage-like extracellular matrix. Its treatment poses major challenges, since chondrosarcoma is resistant to chemotherapy and radiotherapy. Consequently, chondrosarcoma treatment has been limited over the past 30 years, and consists in the surgical resection of the tumor. Increasing evidence suggests that future cancer therapies will be enhanced by the combination of epigenetic and conventional antitumor agents, leading to further investigations to combine 3-Deazaneplanocin A (DZNep), an epigenetic drug, with existing antitumoral agents. We show by in vitro and in vivo experiments that an optimised DZNep/cisplatin combination reduces chondrosarcoma viability and induces apoptosis more effectively than each of the drugs alone. These results demonstrate the potential use of this epigenetic-chemotherapeutic combination approach for further studies and management of chondrosarcoma treatment.Background: We have previously shown that 3-Deazaneplanocin A (DZNep) induces apoptosis in chondrosarcomas. Herein, we tested whether the combination of this epigenetic drug to a standard anticancer therapy may enhance the response to each drug in these bone tumors. Methods: Two chondrosarcoma cell lines (SW1353 and JJ012) were cultured in the presence of DZNep and/or cisplatin. Cell growth was evaluated by counting viable cells, and apoptosis was determined by Apo2.7 expression by flow cytometry. In vivo, the antitumoral effect of the DZNep/cisplatin combination was assessed through measurements of tumor volume of JJ012 xenografts in nude mice. Results: In vitro, the DZNep/cisplatin combination reduced cell survival and increased apoptosis compared to each drug alone in chondrosarcomas, but not in normal cells (chondrocytes). This enhancement of the antitumoral effect of the DZNep/cisplatin combination required a priming incubation with DZNep before the co-treatment with DZNep/cisplatin. Furthermore, in the chondrosarcoma xenograft mice model, the combination of both drugs more strongly reduced tumor growth and induced more apoptosis in tumoral cells than each of the drugs alone. Conclusion: Our results show that DZNep exposure can presensitize chondrosarcoma cells to a standard anticancer drug, emphasizing the promising clinical utilities of epigenetic-chemotherapeutic drug combinations in the future treatment of chondrosarcomas.

Abstract 1944: Navitoclax enhances the efficacy of copanlisib predominantly through inhibition of BCLxL in PIK3CA mutant colorectal cancer

Abstract Background: Mutations in PIK3CA occur in 18% of colorectal cancers (CRC) and result in constitutive activation of the PI3K pathway. Previous work from our lab has determined that MTORC1/2 inhibition, with copanlisib (cop), a PI3K/MTOR inhibitor, is sufficient to induce a treatment response. We hypothesized that the BCL2 family inhibitor navitoclax (nav), a BCL2/BCLxL inhibitor, would enhance the therapeutic response of cop and increase the induction of apoptosis. Methods: Murine derived cancer organoids (MDCOs) were generated from adenocarcinomas arising in Apc and Pik3ca mutant transgenic mice ((FVB x B6) F1 Apcfl/+ Pik3caH1047R/+). MDCOs were plated and matured for 24 hours. MDCOs were treated for 48 hours. Change in diameter was used to assess response. Additionally, human 2D isogenic cell lines SW48 and SW48PIK3CA-H1047R (SW48PK) were plated and treated for 48 hours. WST-1 proliferation assay was used to determine response. In vivo response was assessed as median relative change (MRC) in tumor volume of SW48 and SW48PK xenografts in immunocompromised Rag2-Il2rg-/- (R2G2) mice. Induction of apoptosis was determined with immunoblotting (IB) for PARP cleavage. Results: MDCOs were treated with cop (200nM) or nav (250nM) alone and in combination. Single agent cop resulted in -16% MRC (p&amp;lt;0.001). Nav alone did not have an effect (+95% p&amp;lt;0.07). Enhanced therapeutic response was seen in the combination therapy compared to cop alone (cop -16% vs combo -100%; p&amp;lt;0.001). In SW48 and SW48PK with cop (1nM or 10nM) or nav (250nM) alone and in combination, a greater response was seen in the combination therapy in both cell lines compared to either single agent alone (p&amp;lt;0.005). SW48 and SW48PK xenograft studies demonstrated significant activity of this combination in vivo. SW48 tumor growth was limited with either cop (10mg/kg), nav (80mg/kg), or the combination compared to control (control +5.0 MRC, cop +3.4, nav +2.6, combo +2.6; control vs combo p&amp;lt;0.01; cop vs combo p=0.29). Enhanced activity of this combination was observed in SW48PK tumors compared to SW48. Growth was significantly more limited with the combination (control +5.0 MRC, cop +3.4, nav +4.5, combo +0.7; control vs combo p&amp;lt;0.01; cop vs combo p=0.06). IB of cleaved PARP showed induction of apoptosis was the highest in the combination therapy in all in vitro models and seen as early as 6 hours post treatment. To identify which BCL2 family member nav was primarily targeting, cop was combined with WEHI539 (BCLxL inhibitor; 250nM) or ABT199 (BCL2 inhibitor; 250nM). BCL2 inhibition did not enhance the efficacy of cop in the MDCOs or isogenic lines. However, BCLxL inhibition did enhance the efficacy of cop in both in vitro models. Conclusion: These data indicate that navitoclax, through BCLxL inhibition, enhances the efficacy of copanlisib with a greater induction of apoptosis in several models of PIK3CA mutant CRC. Citation Format: Rebecca Anna DeStefanis, Alyssa DeZeeuw, Gioia Sha, Autumn Olson, Samantha J. Anderson, Christopher P. Babiarz, Cheri A. Pasch, Linda Clipson, Dustin A. Deming. Navitoclax enhances the efficacy of copanlisib predominantly through inhibition of BCLxL in PIK3CA mutant colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1944.

Abstract 2929: Comparative analysis of circulating human tumor DNA and bioluminescent imaging in monitoring tumor burden and therapeutic response of ionizing radiation in intratibial human prostate tumor xenografts

Abstract Purpose/Objective: Pre-clinical models of prostate cancer (PCa) metastases provide critical insight into tumor biology and therapeutic response. Current models require sophisticated reporter transgene models and/or expensive tools to noninvasively monitor tumors in metastatic sites, such as bone. Recent developments in the measurement of circulating tumor DNA (ctDNA) provide an alternative method to noninvasively assess tumor burden at a low cost. Here we present a comparative analysis of human PCa xenograft tumor growth and therapeutic response by simultaneous measurement of ctDNA and bioluminescence. Materials and methods: Male athymic nude mice were used for intra-tibial (n=10) modeling. LNCaP-CMV-Luc cells were implanted in the tibial medullary canal. Tumor burden was evaluated at pre and post-IR (focal exposure 6 Gy on day 28 post-implantation) time-points by in vivo bioluminescent imaging and quantitative real-time polymerase chain reaction (qPCR) for human LINE1/Alu DNA. qPCR was performed on plasma-derived DNA consecutively on the same day as bioluminescence. Results: Human genomic DNA quantification was sensitive to 0.1 pg and linear by hAlu (R2=0.98, for 0.1pg-150ng) and LINE DNA (R2=0.99, for 0.1pg-150ng) qPCR. hAlu DNA qPCR produces a much lower Ct value when compared to LINE1; possibly due to its higher copies in the human genome (Ct value 28 versus 22/0.1 pg). Following tumor inoculation, ctDNA level and tumor bioluminescence were strongly and significantly correlated over time (LINE1, r=0.65 and Alu, r=0.59, p&amp;lt;0.002). Following radiation, we observed an immediate (day 32) but transient decrease in the levels of ctDNA and bioluminescence, followed by a gradual increase due to tumor relapse. The correlation between ctDNA level and bioluminescence was not maintained, but responses followed a similar trend. Conclusions: In the present study, we report that the volume of human PCa xenografts can be accurately measured in the intra-tibial compartments of athymic nude mice by qPCR of circulating human Alu and LINE1 elements. Plasma-derived ctDNA levels highly correlated with tumor bioluminescence over time. Tumor directed radiation therapy exhibited slightly differential responses in ctDNA level and tumor bioluminescence, but overall both measurements followed a similar trend. Citation Format: Alok Mishra, Kenji Zennami, Esteban Velarde, Jonathan B. Coulter, Srinivasan Yegnasubramanian, Shawn E. Lupold, Theodore L. DeWeese. Comparative analysis of circulating human tumor DNA and bioluminescent imaging in monitoring tumor burden and therapeutic response of ionizing radiation in intratibial human prostate tumor xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2929.

RAD001 targeted HUVECs reverses 12-lipoxygenase-induced angiogenesis in oesophageal squamous cell carcinoma.

12‐LOX plays an important role in the progression of various malignancies. However, the underlying mechanisms of the action of 12‐LOX and tumour treatment strategies remain not fully defined. In this study, we investigated the possible roles of 12‐LOX in ESCC and explored the new therapeutic target. Approximately 73% of ESCC tissues showed marked up‐regulation of 12‐LOX, which was associated with poor prognosis. 12‐LOX overexpression was positively correlated with the malignant progression of ESCC as demonstrated both in vitro and in vivo. Up‐regulation of 12‐LOX significantly increased the proliferation of ESCC cells and the xenograft volume. Moreover, 12‐LOX up‐regulation promoted tube formation of HUVECs and tumour angiogenesis in xenografts. Mechanism investigation indicated that 12‐LOX overexpression led to activation of the PI3K/AKT/mTOR pathway and the up‐regulation of VEGF in ESCC cells. Subsequent analysis indicated that the RAD001 could reverse the 12‐LOX‐induced promoting effect on ESCC. Specifically, the application of RAD001 inhibited the proliferation of ESCC cells and the tube‐forming ability of HUVECs. In the drug group, the xenografts exhibited significant volume reduction and angiogenesis inhibition. We demonstrated that RAD001 could inhibit HUVEC migration. These findings presented the evidence that RAD001 had distinct roles on HUVECs and could exert anti‐tumour effects by targeting not only the PI3K/AKT/mTOR pathway but the angiogenesis in ESCC.