KCa channel targeting impairs DNA repair and invasiveness of patient-derived glioblastoma stem cells in culture and orthotopic mouse xenografts which only in part is predictable by KCa expression levels.

Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance particularly of mesenchymal glioblastoma stem-like cells (GSCs) has been proposed to contribute to therapy failure. Recently, we have shown that a mesenchymal-to-proneural mRNA signature of patient derived GSC-enriched (pGSC) cultures associates with in vitro radioresistance and gel invasion. Importantly, this pGSC mRNA signature is prognostic for patients' tumor recurrence pattern and overall survival. Two mesenchymal markers of the mRNA signature encode for IKCa and BKCa Ca2+-activated K+ channels. Therefore, we analyzed here the effect of IKCa- and BKCa-targeting concomitant to (fractionated) irradiation on radioresistance and glioblastoma spreading in pGSC cultures and in pGSC-derived orthotopic xenograft glioma mouse models. To this end, in vitro gel invasion, clonogenic survival, in vitro and in vivo residual DNA double strand breaks (DSBs), tumor growth, and brain invasion were assessed in the dependence on tumor irradiation and K+ channel targeting. As a result, the IKCa- and BKCa-blocker TRAM-34 and paxilline, respectively, increased number of residual DSBs and (numerically) decreased clonogenic survival in some but not in all IKCa- and BKCa-expressing pGSC cultures, respectively. In addition, BKCa- but not IKCa-blockade slowed-down gel invasion in vitro. Moreover, systemic administration of TRAM-34 or paxilline concomitant to fractionated tumor irradiation increased in the xenograft model(s) residual number of DSBs and attenuated glioblastoma brain invasion and (numerically) tumor growth. We conclude, that KCa-blockade concomitant to fractionated radiotherapy might be a promising new strategy in glioblastoma therapy.

Investigating Ras homolog gene family member C (RhoC) and Ki67 expression following external beam radiation therapy show increased RhoC expression in relapsing prostate cancer xenografts.

Ras homolog gene family member C (RhoC) is a GTPase involved in cell migration, implicated in epithelial-mesenchymal transition and treatment resistance and metastasis of cancer. For example, RhoC has been shown to be involved in resistance to radiation in cervical carcinoma. Here, the effect of X-ray irradiation on RhoC expression in prostate cancer (PCa) xenografts was investigated in both xenografts in regression and relapse. Male BALB/cAnNRj-Foxn1nu/nu mice were inoculated with 4-6 million LNCaP-FGC cells and established xenografts were irradiated with X-rays (200 kV, 1 Gymin-1), 5, 10 or 15 Gy using a Gulmay Medical X-ray system. Expression of RhoC and Ki67, a known proliferation marker, was investigated in xenografts, given 15 Gy, 7 days (midst response as measured by size) or 3 weeks (relapse) post irradiation. Staining was quantified using the Halo software (v2.3.2089.34) with the Indica Labs - cytonuclear v1.6 algorithm. RhoC and Ki67 staining was divided into weak, medium, and strong staining and the percentage of cells stained, single and dual staining, was quantified. The HALO software was further used to classify the tissue in each section so that analysis of RhoC and Ki67 expression in cancer cells, stroma and necrotic areas could be done separately. The results showed that RhoC expression in cancer and stroma cells was significantly higher in relapsed xenografts than in those in regression. This was not seen for Ki67 staining, where the percentage of stained cells were the same in regressing and relapsing tumors. RhoC could be a useful biomarker to confirm relapse following external beam radiation therapy.

Analysis of SARS-CoV-2 omicron mutations that emerged during long-term replication in a lung cancer xenograft mouse model.

SARS-CoV-2 Omicron has the largest number of mutations among all the known SARS-CoV-2 variants. The presence of these mutations might explain why Omicron is more infectious and vaccines have lower efficacy to Omicron than other variants, despite lower virulence of Omicron. We recently established a long-term in vivo replication model by infecting Calu-3 xenograft tumors in immunodeficient mice with parental SARS-CoV-2 and found that various mutations occurred majorly in the spike protein during extended replication. To investigate whether there are differences in the spectrum and frequency of mutations between parental SARS-CoV-2 and Omicron, we here applied this model to Omicron. At 30 days after infection, we found that the virus was present at high titers in the tumor tissues and had developed several rare sporadic mutations, mainly in ORF1ab with additional minor spike protein mutations. Many of the mutant isolates had higher replicative activity in Calu-3 cells compared with the original SARS-CoV-2 Omicron virus, suggesting that the novel mutations contributed to increased viral replication. Serial propagation of SARS-CoV-2 Omicron in cultured Calu-3 cells resulted in several rare sporadic mutations in various viral proteins with no mutations in the spike protein. Therefore, the genome of SARS-CoV-2 Omicron seems largely stable compared with that of the parental SARS-CoV-2 during extended replication in Calu-3 cells and xenograft model. The sporadic mutations and modified growth properties observed in Omicron might explain the emergence of Omicron sublineages. However, we cannot exclude the possibility of some differences in natural infection.

The effects of enoxaparin treatment in a xenograft mouse model of oral squamous cell carcinoma: A pilot study.

BACKGROUND: Recent studies suggest that enoxaparin may have therapeutic effects on oral squamous cell carcinoma. We aimed to assess this effect utilizing xenograft mouse model through evaluations of proliferation and angiogenesis markers at the RNA and protein levels. METHODS: Mice were divided into enoxaparin treatment (n = 4), positive control (n = 4) and negative control (n = 3) groups. Immunohistochemical analyses were performed utilizing Bcl-2, Bax and Ki-67 antibodies. Expression levels of proliferation and apoptosis related genes were calculated utilizing qRT-PCR. Time-dependent proliferation assays were performed in OSC-19 and HEK293 cell-lines. RESULTS: Bax antibody showed positive staining in the cytoplasm and nuclei of tumor cells, while Bcl-2 antibody displayed staining only in the cytoplasm. A proliferation index of 15%-20% was found in all groups with the Ki-67 marker indicating no metastasis. Enoxaparin treatment caused decrease in BCL2, BAX and CCNB1 genes' expressions. Compared to HEK293, proliferation assays demonstrated higher division rates in OSC-19 with a significant decrease in viability after 96 h. CONCLUSION: Reduced BCL-2 expression indicates a regression of tumor growth, but reduced BAX expression is not correlated with increased apoptosis. Despite the aggressive nature of OSC-19, our results showed a low cell viability with a high division rate when compared with the control HEK293. This paralleled our in vivo findings that showed absence of lymph node metastasis across all mice groups. This discrepancy with the literature suggests that further investigations of the underlying mechanisms and protein-level analyses are needed to draw definitive conclusions about the effect of enoxaparin on OSC-19 behavior.

Comparative Evaluation of STEAP1 Targeting Chimeric Antigen Receptors with Different Costimulatory Domains and Spacers.

We have developed a chimeric antigen receptor (CAR) against the six-transmembrane epithelial antigen of prostate-1 (STEAP1), which is expressed in prostate cancer, Ewing sarcoma, and other malignancies. In the present study, we investigated the effect of substituting costimulatory domains and spacers in this STEAP1 CAR. We cloned four CAR constructs with either CD28 or 4-1BB costimulatory domains, combined with a CD8a-spacer (sp) or a mutated IgG-spacer. The CAR T-cells were evaluated in short- and long-term in vitro T-cell assays, measuring cytokine production, tumor cell killing, and CAR T-cell expansion and phenotype. A xenograft mouse model of prostate cancer was used for in vivo comparison. All four CAR constructs conferred CD4+ and CD8+ T cells with STEAP1-specific functionality. A CD8sp_41BBz construct and an IgGsp_CD28z construct were selected for a more extensive comparison. The IgGsp_CD28z CAR gave stronger cytokine responses and killing in overnight caspase assays. However, the 41BB-containing CAR mediated more killing (IncuCyte) over one week. Upon six repeated stimulations, the CD8sp_41BBz CAR T cells showed superior expansion and lower expression of exhaustion markers (PD1, LAG3, TIGIT, TIM3, and CD25). In vivo, both the CAR T variants had comparable anti-tumor activity, but persisting CAR T-cells in tumors were only detected for the 41BBz variant. In conclusion, the CD8sp_41BBz STEAP1 CAR T cells had superior expansion and survival in vitro and in vivo, compared to the IgGsp_CD28z counterpart, and a less exhausted phenotype upon repeated antigen exposure. Such persistence may be important for clinical efficacy.

Chrysomycin A Regulates Proliferation and Apoptosis of Neuroglioma Cells via the Akt/GSK-3ß Signaling Pathway In Vivo and In Vitro.

Glioblastoma (GBM) is a major type of primary brain tumor without ideal prognosis and it is therefore necessary to develop a novel compound possessing therapeutic effects. Chrysomycin A (Chr-A) has been reported to inhibit the proliferation, migration and invasion of U251 and U87-MG cells through the Akt/GSK-3ß signaling pathway, but the mechanism of Chr-A against glioblastoma in vivo and whether Chr-A modulates the apoptosis of neuroglioma cells is unclear. The present study aims to elucidate the potential of Chr-A against glioblastoma in vivo and how Chr-A modulates the apoptosis of neuroglioma cells. Briefly, the anti-glioblastoma activity was assessed in human glioma U87 xenografted hairless mice. Chr-A-related targets were identified via RNA-sequencing. Apoptotic ratio and caspase 3/7 activity of U251 and U87-MG cells were assayed via flow cytometry. Apoptosis-related proteins and possible molecular mechanisms were validated via Western blotting. The results showed that Chr-A treatment significantly inhibits glioblastoma progression in xenografted hairless mice, and enrichment analysis suggested that apoptosis, PI3K-Akt and Wnt signaling pathways were involved in the possible mechanisms. Chr-A increased the apoptotic ratio and the activity of caspase 3/7 in U251 and U87-MG cells. Western blotting revealed that Chr-A disturbed the balance between Bax and Bcl-2, activating a caspase cascade reaction and downregulating the expression of p-Akt and p-GSK-3ß, suggesting that Chr-A may contribute to glioblastoma regression modulating in the Akt/GSK-3ß signaling pathway to promote apoptosis of neuroglioma cells in vivo and in vitro. Therefore, Chr-A may hold therapeutic promise for glioblastoma.

TP5: A Novel Therapeutic Approach Targeting Aberrant and Hyperactive CDK5/p25 for the Treatment of Colorectal Carcinoma.

Colorectal carcinoma (CRC) is a prevalent cancer worldwide with a high mortality rate. Evidence suggests that increased expression of Cyclin-dependent kinase 5 (CDK5) contributes to cancer progression, making it a promising target for treatment. This study examined the efficacy of selectively inhibiting CDK5 in colorectal carcinoma using TP5, a small peptide that selectively inhibits the aberrant and hyperactive CDK5/p25 complex while preserving physiological CDK5/p35 functions. We analyzed TP5's impact on CDK5 activity, cell survival, apoptosis, the cell cycle, DNA damage, ATM phosphorylation, and reactive oxygen species (ROS) signaling in mitochondria, in CRC cell lines, both alone and in combination with chemotherapy. We also assessed TP5's efficacy on a xenograft mouse model with HCT116 cells. Our results showed that TP5 decreased CDK5 activity, impaired cell viability and colony formation, induced apoptosis, increased DNA damage, and led to the G1 phase arrest of cell cycle progression. In combination with irinotecan, TP5 demonstrated a synergy by leading to the accumulation of DNA damage, increasing the γH2A.X foci number, and inhibiting G2/M arrest induced by Sn38 treatment. TP5 alone or in combination with irinotecan increased mitochondrial ROS levels and inhibited tumor growth, prolonging mouse survival in the CRC xenograft animal model. These results suggest that TP5, either alone or in combination with irinotecan, is a promising therapeutic option for colorectal carcinoma.

Anticancer effect of locally applicable aptamer-conjugated gemcitabine-loaded atelocollagen patch in pancreatic cancer patient-derived xenograft models.

We investigated the anticancer effect of the aptamer-conjugated gemcitabine-loaded atelocollagen patch in a pancreatic cancer patient-derived xenograft (PDX) model to propose a future potential adjuvant surgical strategy during curative pancreatic resection for pancreatic cancer. A pancreatic cancer PDX model was established. Animals were grouped randomly into a no-treatment control group; treatment group treated with intraperitoneal gemcitabine injection (IP-GEM) or aptamer-conjugated gemcitabine (APT:GEM); and transplant with three kinds of patches: atelocollagen-aptamer-gemcitabine (patch I), atelocollagen-inactive aptamer-gemcitabine (patch II), and atelocollagen-gemcitabine (patch III). Tumor volumes and response were evaluated based on histological analysis by H&E staining and Immunohistochemistry (IHC) was performed. Anticancer therapy-related toxicity was evaluated by hematologic findings. The patch I group showed the most significant reduction of tumor growth rate, compared with the no-treatment group (p < 0.05). However, other treatment groups were not found to show significant reduction in tumor growth rate (0.05 < p < 0.1). There was no microscopic evidence suggesting potential toxicity, such as inflammation, nor necrotic changes in liver, lung, kidney, and spleen tissue. In addition, no leukopenia, anemia, or neutropenia was observed in the patch I group. This implantable aptamer-drug conjugate system is thought to be a new surgical strategy to augment the oncologic significance of margin-negative resection in treating pancreatic cancer in near future.

Tumorigenicity Assessment of Human Cancer Cell Lines Xenografted on Immunodeficient Mice as Positive Controls of Tumorigenicity Testing.

Recent advances in human pluripotent stem cell (hPSC)-derived cell therapies and genome editing technologies such as CRISPR/Cas9 make regenerative medicines promising for curing diseases previously thought to be incurable. However, the possibility of off-target effects during genome editing and the nature of hPSCs, which can differentiate into any cell type and infinitely proliferate, inevitably raises concerns about tumorigenicity. Tumorigenicity acts as a major obstacle to the application of hPSC-derived and gene therapy products in clinical practice. Thus, regulatory authorities demand mandatory tumorigenicity testing as a key pre-clinical safety step for the products. In the tumorigenicity testing, regulatory guidelines request to include human cancer cell line injected positive control group (PC) animals, which must form tumors. As the validity of the whole test is determined by the tumor-forming rates (typically above 90%) of PC animals, establishing the stable tumorigenic condition of PC animals is critical for successful testing. We conducted several studies to establish the proper positive control conditions, including dose, administration routes, and the selection of cell lines, in compliance with Good Laboratory Practice (GLP) regulations and/or guidelines, which are essential for pre-clinical safety tests of therapeutic materials. We expect that our findings provide insights and practical information to create a successful tumorigenicity test and its guidelines.

The Tumor Microenvironment Drives Intrahepatic Cholangiocarcinoma Progression.

Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive cancer with limited therapeutic options and short overall survival. iCCA is characterized by a strong desmoplastic reaction in the surrounding ecosystem that likely affects tumoral progression. Overexpression of the Notch pathway is implicated in iCCA development and progression. Our aim was to investigate the effectiveness of Crenigacestat, a selective inhibitor of NOTCH1 signaling, against the cross-talk between cancer cells and the surrounding ecosystem in an in vivo HuCCT1-xenograft model. In the present study, a transcriptomic analysis approach, validated by Western blotting and qRT-PCR on iCCA tumor masses treated with Crenigacestat, was used to study the molecular pathways responsive to drug treatment. Our results indicate that Crenigacestat significantly inhibited NOTCH1 and HES1, whereas tumor progression was not affected. In addition, the drug triggered a strong immune response and blocked neovascularization in the tumor ecosystem of the HuCCT1-xenograft model without affecting the occurrence of fibrotic reactions. Therefore, although these data need further investigation, our observations confirm that Crenigacestat selectively targets NOTCH1 and that the desmoplastic response in iCCA likely plays a key role in both drug effectiveness and tumor progression.

CXCR4, CXCR5 and CD44 May Be Involved in Homing of Lymphoma Cells into the Eye in a Patient Derived Xenograft Homing Mouse Model for Primary Vitreoretinal Lymphoma.

Background: Primary vitreoretinal lymphoma (PVRL), a rare malignancy of the eye, is strongly related to primary central nervous system lymphoma (PCNSL). We hypothesized that lymphoma cells disseminate to the CNS and eye tissue via distinct homing receptors. The objective of this study was to test expression of CXCR4, CXCR5, CXCR7 and CD44 homing receptors on CD20 positive B-lymphoma cells on enucleated eyes using a PCNSL xenograft mouse model. Methods: We used indirect immunofluorescence double staining for CD20/CXCR4, CD20/CXCR5, CD20/CXCR7 and CD20/CD44 on enucleated eyes of a PCNSL xenograft mouse model with PVRL phenotype (PCNSL group) in comparison to a secondary CNS lymphoma xenograft mouse model (SCNSL group). Lymphoma infiltration was evaluated with an immunoreactive score (IRS). Results: 11/13 paired eyes of the PCNSL but none of the SCNSL group were infiltrated by CD20-positive cells. Particularly the choroid and to a lesser extent the retina of the PCNSL group were infiltrated by CD20+/CXCR4+, CD20+/CXCR5+, few CD20+/CD44+ but no CD20+/CXCR7+ cells. Expression of CXCR4 (p = 0.0205), CXCR5 (p = 0.0004) and CD44 (p < 0.0001) was significantly increased in the PCNSL compared to the SCNSL group. Conclusions: CD20+ PCNSL lymphoma cells infiltrating the eye co-express distinct homing receptors such as CXCR4 and CXCR5 in a PVRL homing mouse model. These receptors may be involved in PVRL homing into the eye.

Infiltration of Immune Competent Cells into Primary Tumors and Their Surrounding Connective Tissues in Xenograft and Syngeneic Mouse Models.

To fight cancer more efficiently with cell-based immunotherapy, more information about the cells of the immune system and their interaction with cancer cells in vivo is needed. Therefore paraffin wax embedded primary breast cancers from the syngeneic mouse WAP-T model and from xenografted tumors of breast, colon, melanoma, ovarian, neuroblastoma, pancreatic, prostate, and small cell lung cancer were investigated for the infiltration of immunocompetent cells by immunohistochemistry using antibodies against leukocyte markers. The following markers were used: CD45 as a pan-leukocyte marker, BSA-I as a dendritic cell marker, CD11b as an NK cell marker, and CD68 as a marker for macrophages. The labeled immune cells were attributed to the following locations: adjacent adipose tissue, tumor capsule, intra-tumoral septae, and cancer cells directly. In xenograft tumors, the highest score of CD45 and CD11b positive, NK, and dendritic cells were found in the adjacent adipose tissue, followed by lesser infiltration directly located at the cancer cells themselves. The detected numbers of CD45 positive cells differed between the tumor entities: few infiltrating cells in breast cancer, small cell lung cancer, neuroblastoma, a moderate infiltration in colon cancer, melanoma and ovarian cancer, strongest infiltration in prostate and pancreatic cancer. In the syngeneic tumors, the highest score of CD45 and CD11b positive, NK and dendritic cells were observed in the tumor capsule, followed by a lesser infiltration of the cancer tissue. Our findings argue for paying more attention to investigate how immune-competent cells can reach the tumor cells directly.

Anticancer Characteristics of Fomitopsis pinicola Extract in a Xenograft Mouse Model-a Preliminary Study.

Introduction: Medicinal mushrooms have been used for the treatment of diseases and general promotion of health for many centuries. Recent pharmacological research into medicinal mushrooms has identified various therapeutic properties, with applications in modern medicine.Aim: To evaluate the anti-cancer activities of Fomitopsis pinicola (F. pinicola) alcoholic extract in an in vivo setting.Methods: The anti-tumour effect of the F. pinicola extract was tested in a xenograft immune-compromised Rag-1 mouse model. This was followed by RT-PCR and metabolomics analyses.Results: There were no observable differences in tumor growth between treated and non-treated groups. The bioactive components were not detected in the mouse plasma or the tumor site.Conclusions: The extract was poorly absorbed; this is likely due to the timing of treatment, dosage levels and modifications made to the extract where the alcohol-based solvent was replaced with water. This, in combination with fractionation studies which identified most anti-cancer compounds to be hydrophobic, largely explained the lack of anti-cancer activities in vivo.

LY75 Suppression in Mesenchymal Epithelial Ovarian Cancer Cells Generates a Stable Hybrid EOC Cellular Phenotype, Associated with Enhanced Tumor Initiation, Spreading and Resistance to Treatment in Orthotopic Xenograft Mouse Model.

The implications of the epithelial-mesenchymal transition (EMT) mechanisms in the initiation and progression of epithelial ovarian cancer (EOC) remain poorly understood. We have previously shown that suppression of the antigen receptor LY75 directs mesenchymal-epithelial transition (MET) in EOC cell lines with the mesenchymal phenotype, associated with the loss of Wnt/ß-catenin signaling activity. In the present study, we used the LY75-mediated modulation of EMT in EOC cells as a model in order to investigate in vivo the specific role of EOC cells, with an epithelial (E), mesenchymal (M) or mixed epithelial plus mesenchymal (E+M) phenotype, in EOC initiation, dissemination and treatment response, following intra-bursal (IB) injections of SKOV3-M (control), SKOV3-E (Ly75KD) and a mixed population of SKOV3-E+M cells, into severe combined immunodeficiency (SCID) mice. We found that the IB-injected SKOV3-E cells displayed considerably higher metastatic potential and resistance to treatment as compared to the SKOV3-M cells, due to the acquisition of a Ly75KD-mediated hybrid phenotype and stemness characteristics. We also confirmed in vivo that the LY75 depletion directs suppression of the Wnt/ß-catenin pathway in EOC cells, suggestive of a protective role of this pathway in EOC etiology. Moreover, our data raise concerns regarding the use of LY75-targeted vaccines for dendritic-cell EOC immunotherapy, due to the possible occurrence of undesirable side effects.

Fascin-1 enhances experimental osteosarcoma tumor formation and metastasis and is related to poor patient outcome.

BACKGROUND: Fascin-1, a prominent actin-bundling protein, is found to be upregulated in several human carcinomas. While it is accepted that Fascin-1 expression correlates with poor clinical outcome and decreased survival in various carcinomas, its role in sarcoma such as osteosarcoma (OS) remains unknown. In the present study, we evaluated the prognostic value and biological relevance of Fascin-1 in OS. METHODS: The correlation between Fascin-1 expression and the outcome of OS patients was determined by immunohistochemistry analysis of Fascin-1 expression in a tissue microarray of OS tissue specimens collected during primary tumor resection. To examine the effect of Fascin-1, shRNA and overexpression technology to alter Fascin-1 levels in OS cells were used in cellular assays as well as in intratibial xenograft OS models in SCID mice. RESULTS: Kaplan-Meier survival analysis of Fascin-1 expression in OS tumor specimens revealed a direct relationship between Fascin-1 expression and poor patient survival. Furthermore, overexpression of Fascin-1 in OS cells significantly increased their migratory capacity as well as the activity of the matrix metalloprotease MMP-9, known to be critical for the execution of metastasis. Finally, using relevant xenograft mouse models, orthotopic intratibial transplantation of two different OS cell lines overexpressing Fascin-1 promoted tumor growth and lung metastasis. CONCLUSIONS: Collectively, our findings demonstrate for the first time that Fascin-1 has considerable potential as a novel prognostic biomarker in OS, and suggest that targeting of Fascin-1 might be a new anti-metastatic strategy in OS patient treatment.

Design, synthesis, in vitro and in vivo evaluation, and structure-activity relationship (SAR) discussion of novel dipeptidyl boronic acid proteasome inhibitors as orally available anti-cancer agents for the treatment of multiple myeloma and mechanism studies.

A series of novel dipeptidyl boronic acid inhibitors of 20S proteasome were designed and synthesized. Aliphatic groups at R1 position were designed for the first time to fully understand the SAR (structure-activity relationship). Among the screened compounds, novel inhibitor 5c inhibited the CT-L (chymotrypsin-like) activity with IC50 of 8.21 nM and the MM (multiple myeloma) cells RPMI8226, U266B and ARH77 proliferations with the IC50 of 8.99, 6.75 and 9.10 nM, respectively, which showed similar in vitro activities compared with the compound MLN2238 (biologically active form of marketed MLN9708). To investigate the oral availability, compound 5c was esterified to its prodrug 6a with the enzymatic IC50 of 6.74 nM and RPMI8226, U266B and ARH77 cell proliferations IC50 of 2.59, 4.32 and 3.68 nM, respectively. Furthermore, prodrug 6a exhibited good pharmacokinetic properties with oral bioavailability of 24.9%, similar with MLN9708 (27.8%). Moreover, compound 6a showed good microsomal stabilities and displayed stronger in vivo anticancer efficacy than MLN9708 in the human ARH77 xenograft mouse model. Finally, cell cycle results showed that compound 6a had a significant inhibitory effect on CT-L and inhibited cell cycle progression at the G2M stage.

Effect of dasatinib in a xenograft mouse model of canine histiocytic sarcoma and in vitro expression status of its potential target EPHA2.

Canine histiocytic sarcoma (HS) is an aggressive and highly metastatic tumor. Previously, the kinase inhibitor dasatinib was shown to have potent growth inhibitory activity against HS cells in vitro, possibly via targeting the EPHA2 receptor. Here, the in vivo effect of dasatinib in HS cells was investigated using a xenograft mouse model. Moreover, the expression status of EPHA2 was examined in six HS cell lines, ranging from insensitive to highly sensitive to dasatinib. In the HS xenograft mouse model, dasatinib significantly suppressed tumor growth, as illustrated by a decrease in mitotic and Ki67 indices and an increase in apoptotic index in tumor tissues. On Western blot analysis, EPHA2 was only weakly detected in all HS cell lines, regardless of sensitivity to dasatinib. Dasatinib likely results in the inhibition of xenograft tumor growth via a mechanism other than targeting EPHA2. The findings of this study suggest that dasatinib is a targeted therapy drug worthy of further exploration for the treatment of canine HS.

Exploration of anti-cancer effects and mechanisms of Zuo-Jin-Wan and its alkaloid components in vitro and in orthotopic HepG2 xenograft immunocompetent mice.

BACKGROUND: Zuo-Jin-Wan (ZJW), a two-herb formula consisting of Coptis chinensis (CC) and Evodia rutaecarpa (ER), is commonly used in traditional Chinese medicine for the treatment of cancers. However, the efficacies and mechanisms of ZJW and its alkaloid components on cancers are still unclear. METHODS: Here we investigated the anti-cancer effects and mechanisms of ZJW, CC, ER, berberine, and evodiamine in cells and in intrahepatic xenograft mice. RESULTS: Treatment of HepG2 cells with ZJW, CC, ER, berberine, and evodiamine significantly displayed cytotoxic effects in a dose- and time-dependent manner. Hierarchical cluster analysis of gene expression profiles showed that CC and ZJW shared a similar mechanism for the cytotoxic effects, suggesting that CC was the active ingredient of ZJW for anti-cancer activity. Network analysis further showed that c-myc was the likely key molecule involved in the regulation of ZJW-affected gene expression. A human hepatoma xenograft model was established by intrahepatic injection of HepG2 cells containing nuclear factor-κB-driven luciferase genes in immunocompetent mice. In vivo bioluminescence imaging showed that cells had been successfully transplanted in mouse liver. Oral administration of ZJW for 28 consecutive days led to a significant decrease in the accumulation of ascites, the ratio of tumor-to-liver, and the number of transplanted cells in livers. CONCLUSIONS: In conclusion, our findings suggested for the first time that ZJW significantly suppressed human cancer cell growth in orthotopic HepG2 xenograft-bearing immunocompetent mice. Moreover, c-myc might play a potent role in the cytotoxic mechanisms of ZJW, CC, ER, berberine, and evodiamine.

CASTIN: a system for comprehensive analysis of cancer-stromal interactome.

BACKGROUND: Cancer microenvironment plays a vital role in cancer development and progression, and cancer-stromal interactions have been recognized as important targets for cancer therapy. However, identifying relevant and druggable cancer-stromal interactions is challenging due to the lack of quantitative methods to analyze whole cancer-stromal interactome. RESULTS: We present CASTIN (CAncer-STromal INteractome analysis), a novel framework for the evaluation of cancer-stromal interactome from RNA-Seq data using cancer xenograft models. For each ligand-receptor interaction which is derived from curated protein-protein interaction database, CASTIN summarizes gene expression profiles of cancer and stroma into three evaluation indices. These indices provide quantitative evaluation and comprehensive visualization of interactome, and thus enable to identify critical cancer-microenvironment interactions, which would be potential drug targets. We applied CASTIN to the dataset of pancreas ductal adenocarcinoma, and successfully characterized the individual cancer in terms of cancer-stromal relationships, and identified both well-known and less-characterized druggable interactions. CONCLUSIONS: CASTIN provides comprehensive view of cancer-stromal interactome and is useful to identify critical interactions which may serve as potential drug targets in cancer-microenvironment. CASTIN is available at: http://github.com/tmd-gpat/CASTIN .