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Omipalisib (GSK2126458), a potent dual PI3K/mTOR inhibitor, is reported to exhibit anti-tumor effect in several kinds of cancers. More than 50% of acute myeloid leukemia (AML) patients display a hyperactivation of PI3K/AKT/mTOR signaling. We investigated the anti-proliferative effect of omipalisib in AML cell lines with varied genetic backgrounds. The OCI-AML3 and THP-1 cell lines had a significant response to omipalisib, with IC50 values of 17.45 nM and 8.93 nM, respectively. We integrated transcriptomic profile and metabolomic analyses, and followed by gene set enrichment analysis (GSEA) and metabolite enrichment analysis. Our findings showed that in addition to inhibiting PI3K/AKT/mTOR signaling and inducing cell cycle arrest at the G0/G1 phase, omipalisib also suppressed mitochondrial respiration and biogenesis. Furthermore, omipalisib downregulated several genes associated with serine, glycine, threonine, and glutathione metabolism, and decreased their protein and glutathione levels. In vivo experiments revealed that omipalisib significantly inhibited tumor growth and prolonged mouse survival without weight loss. Gedatolisib and dactolisib, another two PI3K/mTOR inhibitors, exerted similar effects without affecting mitochondria biogenesis. These results highlight the multifaceted anti-leukemic effect of omipalisib, revealing its potential as a novel therapeutic agent in AML treatment.

Purpose: To clarify the effects of cyclin E1 suppression on antitumor efficacy of sorafenib in hepatocellular carcinoma cells and to explore the potential of combining sorafenib with cyclin-dependent kinase (CDK) inhibition in therapy.Experimental Design: The effects of cyclin E1 suppression on sorafenib-induced apoptosis were tested in both sorafenib-sensitive (Huh-7 and HepG2, IC50 5–6 μmol/L) and sorafenib-resistant (Huh-7R and HepG2R, IC50 14–15 μmol/L) hepatocellular carcinoma cells. The activity of pertinent signaling pathways and the expression of cell cycle and apoptosis-related proteins were measured using Western blotting. Efficacy of sorafenib combined with the pan-CDK inhibitor flavopiridol was tested both in vitro and in xenograft experiments. The pertinent downstream mediators of antitumor efficacy were tested in transient transfection and RNA interference experiments.Results: Cyclin E1 mRNA and protein expressions were suppressed after sorafenib treatment in sorafenib-sensitive but not in sorafenib-resistant hepatocellular carcinoma cells. Changes in cyclin E2 or D1 were not correlated with sorafenib sensitivity. The knockdown of cyclin E1 expression reversed the resistance of hepatocellular carcinoma cells to sorafenib in terms of cell growth and apoptosis induction, whereas the overexpression of cyclin E1 increased the resistance to sorafenib. The growth-inhibitory and apoptosis-inducing effects of sorafenib were enhanced by flavopiridol, and Mcl-1 suppression was determined to play a critical role in mediating this enhancing effect.Conclusions: The cyclin E1 suppression in hepatocellular carcinoma cells may serve as a pharmacodynamic biomarker for predicting sorafenib efficacy. The combination of sorafenib and CDK inhibitors may improve the efficacy of sorafenib in hepatocellular carcinoma. Clin Cancer Res; 22(10); 2555–64. ©2015 AACR.

Supplement Figure S1: The six E2Fs binding sites in cyclin E1 promoter; Supplement Figure S2: Suppression of cyclin E1 by sorafenib correlated with sorafenib sensitivity; Supplement Figure S3: Effects of sorafenib and the Raf kinase inhibitor on cyclin E1 suppression in HCC cells; Supplement Figure S4: Knockdown of cyclin E1, but not cyclin E2, significantly increased the sensitivity to sorafenib in HCC cells; Supplement Figure S5: Effects of cyclin E1 or Mcl-1 inhibition on sorafenib-induced apoptosis; Supplement Figure S6: Effects of E2F1 suppression on cyclin E1 expression; Supplement Figure S7: Effects of flavopiridol on cyclin E1 and Rb protein levels in HCC cells; Supplement Figure S8: Synergistic anti-tumor activity between sorafenib and the CDK inhibitor flavopiridol; Supplement Figure S9: Differential effect between sorafenib and the CDK inhibitor flavopiridol on cell-cycle progression of HCC cells; Supplement Figure S10: The apoptosis-related proteins measured by the Human Apoptosis Array kit; Supplement Figure S11: In vivo evidence of toxicity between sorafenib and flavopiridol in HCC cells; Supplement Figure S12: Flavopiridol enhanced the anti-tumor efficacy of sorafenib in vivo; and Supplement Table S1: Primers list and Supplementary materials and methods.

Purpose: Sorafenib has proved survival benefit for patients with advanced hepatocellular carcinoma (HCC). This study explored whether the efficacy of sorafenib can be improved by adding the mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor CI-1040 to vertically block the Raf/MEK/ERK pathway.Experimental Design: The growth inhibitory effects of sorafenib and CI-1040 were tested in HCC cell lines (Huh-7 and Hep3B) and human umbilical vascular endothelial cells (HUVEC). The potential synergistic growth inhibitory effects were measured by median effect analysis. Apoptosis was measured by flow cytometry. The effects on ERK phosphorylation and levels of apoptosis regulatory proteins were measured by Western blotting. The in vivo antitumor activity of sorafenib and CI-1040 were tested in xenograft HCC models.Results: Combination of sorafenib and CI-1040 synergistically inhibited ERK phosphorylation and cell growth and induced apoptosis in both HCC cells and HUVECs. Increased expression of Bim protein, which correlated with the extent of ERK inhibition, was found in both HCC cells and HUVECs. Knockdown of Bim expression by small interfering RNA partially abrogated the synergistic proapoptotic effects of sorafenib and CI-1040. Combination therapy inhibited tumor growth significantly better than either single agent in the xenograft models.Conclusion: The antitumor effects of sorafenib in HCC can be improved by vertical blockade of Raf/MEK/ERK signaling with CI-1040. (Clin Cancer Res 2009;15(18):5820–8)

Clinicopathological characteristics of patients with lung cancer.

The KMT1E mutation (H1224A) does not suppress ANXA2 promoter activity in cancer cells.

Supplementary Figures 1-3, Table 1 from Induction of DNA Damage-Inducible Gene GADD45β Contributes to Sorafenib-Induced Apoptosis in Hepatocellular Carcinoma Cells

revised supporting materials and methods

Supplemental Figure Legends

Cabozantinib is a potent tyrosine kinase inhibitor with multiple targets including MET, VEGFR2, RET, KIT, and FLT3. Cabozantinib is widely used for the treatment of medullary thyroid cancer and renal cell carcinoma. We recently suggested cabozantinib as a potential therapeutic alternative for acute myeloid leukemia (AML) patients with FLT3-internal tandem duplication (FLT3-ITD). Here, we report that cabozantinib can promote differentiation in erythroid leukemia cells. We found that K562 erythroid leukemia cells treated with 1 μM cabozantinib for 72 h underwent erythroid lineage differentiation. Transcriptomic analysis revealed that various pathways associated with heme biosynthesis, hemoglobin production, and GATA1 targets were upregulated, whereas cell survival pathways were downregulated. Further examination revealed that cabozantinib-induced erythroid differentiation is at least in part regulated by JNK activation and phosphorylation. Levels of phosphorylated BCR-ABL, AKT, STAT5, ERK, and p38 also decreased following cabozantinib treatment. Therefore, we indicate that cabozantinib has dual functions. First, it induces K562 cell differentiation toward the erythroid lineage by upregulating heme biosynthesis, globin synthesis, and erythroid-associated reactions. Second, cabozantinib inhibits K562 cell proliferation by inhibiting the phosphorylation of BCR-ABL and the downstream MAPK, PI3K-AKT, and JAK-STAT signaling pathways.

The most prevalent oral cancer globally is oral squamous cell carcinoma (OSCC). The invasion of adjacent bones and the metastasis to regional lymph nodes often lead to poor prognoses and shortened survival times in patients with OSCC. Encouraging immunotherapeutic responses have been seen with immune checkpoint inhibitors (ICIs); however, these positive responses to monotherapy have been limited to a small subset of patients. Therefore, it is urgent that further investigations into optimizing immunotherapies are conducted. Areas of research include identifying novel immune checkpoints and targets and tailoring treatment programs to meet the needs of individual patients. Furthermore, the advancement of combination therapies against OSCC is also critical. Thus, additional studies are needed to ensure clinical trials are successful. Mice models are advantageous in immunotherapy research with several advantages, such as relatively low costs and high tumor growth success rate. This review paper divided methods for establishing OSCC mouse models into four categories: syngeneic tumor models, chemical carcinogen induction, genetically engineered mouse, and humanized mouse. Each method has advantages and disadvantages that influence its application in OSCC research. This review comprehensively surveys the literature and summarizes the current mouse models used in immunotherapy, their advantages and disadvantages, and details relating to the cell lines for oral cancer growth. This review aims to present evidence and considerations for choosing a suitable model establishment method to investigate the early diagnosis, clinical treatment, and related pathogenesis of OSCC.

BACKGROUND: Sorafenib is one of the standard first-line therapies for advanced hepatocellular carcinoma (HCC). Unfortunately, there are currently no appropriate biomarkers to predict the clinical efficacy of sorafenib in HCC patients. MicroRNAs (miRNAs) have been studied for their biological functions and clinical applications in human cancers. METHODS: In this study, we found that miR-10b-3p expression was suppressed in sorafenib-resistant HCC cell lines through miRNA microarray analysis. RESULTS: Sorafenib-induced apoptosis in HCC cells was significantly enhanced by miR-10b-3p overexpression and partially abrogated by miR-10b-3p depletion. Among 45 patients who received sorafenib for advanced HCC, those with high miR-10b-3p levels, compared to those with low levels, exhibited significantly longer overall survival (OS) (median, 13.9 vs. 3.5 months, p = 0.021), suggesting that high serum miR-10b-3p level in patients treated with sorafenib for advanced HCC serves as a biomarker for predicting sorafenib efficacy. Furthermore, we confirmed that cyclin E1, a known promoter of sorafenib resistance reported by our previous study, is the downstream target for miR-10b-3p in HCC cells. CONCLUSIONS: This study not only identified the molecular target for miR-10b-3p, but also provided evidence that circulating miR-10b-3p may be used as a biomarker for predicting sorafenib sensitivity in patients with HCC.

As part of our previous studies on the anti-tumor mechanisms of sorafenib, one of the primary treatments for advanced hepatocellular carcinoma (HCC), we found that suppression of cyclin E1 in HCC cells correlates with sensitivity to sorafenib (Chiun Hsu et al. Clin Cancer Res. 2016:2555). Furthermore, the combination of sorafenib and a cyclin-dependent kinase inhibitor was found to have synergistic anti-tumor effects. Specifically, we found that inhibiting DKK1 (dickkopf1), an essential regulator of Wnt signaling, had a synergistic effect. In sorafenib-sensitive HCC cells, DKK1 mRNA and protein expressions were suppressed following treatment with sorafenib, but not in sorafenib-resistant cells. HCC cells resistant to sorafenib were induced to apoptosis with knockdown of DKK1 expression. The apoptosis-inducing effects of sorafenib were enhanced by DKK1 inhibitors, and beta-catenin suppression was found to be crucial to this effect. In addition, mouse tumors secrete DKK1 into the blood and its presence correlates positively with tumor size and survival during sorafenib treatment. Suppression of DKK1 in hepatocellular carcinoma cells may serve as a pharmacodynamic biomarker for predicting sorafenib or CDK inhibitor efficacy. Sorafenib combined with a DKK1 inhibitor may improve sorafenib's efficacy in hepatocellular carcinoma. (Supported by MOST 106-2314-B-002-229-MY3, MOST 109-2634-F-002-043, MOST 109-2314-B-002-229 -MY3, MOST 110-2634-F-002-044 from Ministry of Science and Technology, Taiwan) Citation Format: Lin Li, Chia-Lang Hsu, Liang-In Lin, Bin-Shyun Lee, Ping-Yun Ou, Ann-Lii Cheng, Chiun Hsu, Da-Liang Ou. DKK1 inhibition can overcome sorafenib resistance in hepatocellular carcinoma cells through beta-catenin suppression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 376.

Metabolic reprogramming of tumors with the accompanying reprogramming of glucose metabolism and production of lactate accumulation is required for the subsequent development of tumors. Recent evidence has indicated that tumor-secreted lactate can promote an oncolytic immune microenvironment within the tumor. Furthermore, tumor-secreted lactate directly induces polarization of tumor-supportive M2 macrophages. However, oxidized tumor-secreted lactate in the tumor microenvironment can be exploited. Iron oxide nanoparticles have shown promising anticancer potential by activating tumor-suppressing macrophages. Furthermore, lactate oxidase (LOX) generally oxidizes tumor-secreted lactate and subsequently converts to pyruvate. Particularly, the ratio of M2 macrophages to M1 macrophages corresponds with tumor growth. In this study, we present iron oxide nanoparticles with carboxylic acid combined with LOX that enhance antitumor efficacy as a synergistic effect on the repolarization of tumor-supportive M2 macrophages to tumor-suppressive M1 macrophages in a tumor microenvironment. After M2 macrophages treated with iron oxide nanoparticles were combined with LOX, the ratio of M1 macrophages was significantly greater than iron oxide nanoparticles alone or with LOX alone. It is concluded that the inhibition of cancer cell proliferation by ratio of M1 macrophages was observed. This study suggests that the iron oxide nanoparticles combined with LOX could be potentially used for potentiating immune checkpoint inhibitor therapies for cancer treatment.

Hepatocellular carcinoma (HCC) is a lethal human malignancy and a leading cause of cancer‐related death worldwide. Patients with HCC are often diagnosed at an advanced stage, and the prognosis is usually poor. The multikinase inhibitor sorafenib is the first‐line treatment for patients with advanced HCC. However, cases of primary or acquired resistance to sorafenib have gradually increased, leading to a predicament in HCC therapy. Thus, it is critical to investigate the mechanism underlying sorafenib resistance. Transactivation response element RNA‐binding protein 2 (TARBP2) is a multifaceted miRNA biogenesis factor that regulates cancer stem cell (CSC) properties. The tumorigenicity and drug resistance of cancer cells are often enhanced due to the acquisition of CSC features. However, the role of TARBP2 in sorafenib resistance in HCC remains unknown. Our results demonstrate that TARBP2 is significantly downregulated in sorafenib‐resistant HCC cells. The TARBP2 protein was destabilized through autophagic–lysosomal proteolysis, thereby stabilizing the expression of the CSC marker protein Nanog, which facilitates sorafenib resistance in HCC cells. In summary, here we reveal a novel miRNA‐independent role of TARBP2 in regulating sorafenib resistance in HCC cells.

e14596 Background: Immune-related adverse events (irAEs) are major hurdle to immune checkpoint blockade (ICB). Corticosteroid (CS) is effective in controlling the majority of irAEs. Although recent studies suggested CS use does not jeopardize the anti-tumor efficacy of ICB, prophylactic use of CS remains prohibited with the concerns of attenuating efficacy of ICB. This study aimed to investigate the effects of CS premedication on the efficacy of ICB in murine hepatocellular carcinoma models. Methods: Anti-mCTLA-4 (9D9C, BMS) and anti-mPD-1 antibodies (4H2, ONO) were intraperitoneally (ip) administered to tumor-bearing mice (subcutaneous Hepa 1-6 model and orthotopic BNL 1MEA.7R.1 model) with or without dexamethasone (DEXA) premedication (10 and 200 μg, equivalent to minimal anti-inflammatory dosage and pulse therapy in human, respectively). Efficacy of ICB was evaluated as tumor shrinkage. Tumor-infiltrating lymphocytes (TILs) were isolated for single cell RNA-sequencing and effector function analysis through flow cytometry. Results: In the subcutaneous model, all tumors treated with ICB alone (N=7) or ICB plus DEXA 10 μg (N=5) completely regressed, but 1 out of 7 tumors treated with ICB plus DEXA 200 μg escaped. However, the tumor growth was not significantly different between groups ( P-value >0.05, multiple Mann-Whitney test). In the orthotopic model (N=5/group), the mean (± standard error) tumor weights on day 21 after tumor implantation for isotype control, ICB, ICB plus DEXA 10 μg and ICB plus DEXA 200 μg were 2.45 (± 0.54), 0.73 (± 0.18), 0.98 (± 0.65), and 0.69 (± 0.17) grams, respectively ( P-value >0.05, comparing ICB plus DEXA 10 or 200 μg with ICB). At transcriptomic level, premedication with either dosage of DEXA significantly reduced the percentage of effector memory cells and increased the percentage of exhausted effector cells in the CD8 TIL population, which appeared to counterbalance the effects of ICB. However, at protein level, premedication of DEXA 10 or 200 μg did not reduce the interferon-γ or granzyme B production of CD8 TILs in both models (Table). Conclusions: CS premedication did not attenuate the efficacy of ICB. Our study provides the scientific basis to evaluate the potential of prophylactic CS in preventing ICB-induced irAEs in clinical studies.[Table: see text]

BackgroundRegorafenib and other multikinase inhibitors may enhance antitumor efficacy of anti-program cell death-1 (anti-PD1) therapy in hepatocellular carcinoma (HCC). Its immunomodulatory effects, besides anti-angiogenesis, were not clearly defined.MethodsIn vivo antitumor efficacy was tested in multiple syngeneic liver cancer models. Murine bone marrow–derived macrophages (BMDMs) were tested in vitro for modulation of polarization by regorafenib and activation of cocultured T cells. Markers of M1/M2 polarization were measured by quantitative reverse transcription PCR (RT-PCR), arginase activity, flow cytometry, and ELISA. Knockdown of p38 kinase and downstream Creb1/Klf4 signaling on macrophage polarization were confirmed by using knockdown of the upstream MAPK14 kinase, chemical p38 kinase inhibitor, and chromatin immunoprecipitation.ResultsRegorafenib (5 mg/kg/day, corresponding to about half of human clinical dosage) inhibited tumor growth and angiogenesis in vivo similarly to DC-101 (anti-VEGFR2 antibody) but produced higher T cell activation and M1 macrophage polarization, increased the ratio of M1/M2 polarized BMDMs and proliferation/activation of cocultured T cells in vitro, indicating angiogenesis-independent immunomodulatory effects. Suppression of p38 kinase phosphorylation and downstream Creb1/Klf4 activity in BMDMs by regorafenib reversed M2 polarization. Regorafenib enhanced antitumor efficacy of adoptively transferred antigen-specific T cells. Synergistic antitumor efficacy between regorafenib and anti-PD1 was associated with multiple immune-related pathways in the tumor microenvironment.ConclusionRegorafenib may enhance antitumor immunity through modulation of macrophage polarization, independent of its anti-angiogenic effects. Optimization of regorafenib dosage for rational design of combination therapy regimen may improve the therapeutic index in the clinic.

Cabozantinib is an orally available, multi-target tyrosine kinase inhibitor approved for the treatment of several solid tumours and known to inhibit KIT tyrosine kinase. In acute myeloid leukaemia (AML), aberrant KIT tyrosine kinase often coexists with t(8;21) to drive leukaemogenesis. Here we evaluated the potential therapeutic effect of cabozantinib on a selected AML subtype characterised by t(8;21) coupled with KIT mutation. Cabozantinib exerted substantial cytotoxicity in Kasumi-1 cells with an IC50 of 88.06 ± 4.32 nM, which was well within clinically achievable plasma levels. The suppression of KIT phosphorylation and its downstream signals, including AKT/mTOR, STAT3, and ERK1/2, was elicited by cabozantinib treatment and associated with subsequent alterations of cell cycle- and apoptosis-related molecules. Cabozantinib also disrupted the synthesis of an AML1-ETO fusion protein in a dose- and time-dependent manner. In a mouse xenograft model, cabozantinib suppressed tumourigenesis at 10 mg/kg and significantly prolonged survival of the mice. Further RNA-sequencing analysis revealed that mTOR-mediated signalling pathways were substantially inactivated by cabozantinib treatment, causing the downregulation of ribosome biogenesis and glycolysis, along with myeloid leukocyte activation. We suggest that cabozantinib may be effective in the treatment of AML with t(8;21) and KIT mutation. Relevant clinical trials are warranted.

Cabozantinib is a potent tyrosine kinase inhibitor with multiple targets including MET, VEGFR2, RET, KIT, and FLT3. Cabozantinib is widely used for the treatment of medullary thyroid cancer and renal cell carcinoma. We recently suggested cabozantinib as a potential therapeutic alternative for acute myeloid leukemia (AML) patients with FLT3-internal tandem duplication (FLT3-ITD). Here, we report that cabozantinib can promote differentiation in erythroid leukemia cells. We found that K562 erythroid leukemia cells treated with 1 μM cabozantinib for 72 h underwent erythroid lineage differentiation. Transcriptomic analysis revealed that various pathways associated with heme biosynthesis, hemoglobin production, and GATA1 targets were upregulated, whereas cell survival pathways were downregulated. Further examination revealed that cabozantinib-induced erythroid differentiation is at least in part regulated by JNK activation and phosphorylation. Levels of phosphorylated BCR-ABL, AKT, STAT5, ERK, and p38 also decreased following cabozantinib treatment. Therefore, we indicate that cabozantinib has dual functions. First, it induces K562 cell differentiation toward the erythroid lineage by upregulating heme biosynthesis, globin synthesis, and erythroid-associated reactions. Second, cabozantinib inhibits K562 cell proliferation by inhibiting the phosphorylation of BCR-ABL and the downstream MAPK, PI3K-AKT, and JAK-STAT signaling pathways.

Multikinase inhibitors with antiangiogenic properties used to be standard therapy for patients with advanced hepatocellular carcinoma (HCC). Recently, several antiangiogenic agents (lenvatinib, cabozantinib, and ramucirumab) have demonstrated antitumor activity for advanced HCC in randomized controlled trials. However, the landscape of drug development for HCC may change dramatically with the advent of immune checkpoint inhibitor therapy, particularly the anti–programmed cell death-1 (anti-PD1) agents. In addition, early-phase clinical trials of combination of anti–PD-1 and antiangiogenic agents have shown very promising anti-tumor activity in patients with advanced HCC. Therefore, the critical research questions at present are whether this combination strategy will be the next generation of standard therapy and which antiangiogenic agents will be the optimal partner for the combination. All of the 4 multikinase inhibitors for HCC (sorafenib, regorafenib, lenvatinib, and cabozantinib) have been reported to have immune modulatory effects. The authors systematically reviewed the pre-clinical evidence of their immune modulatory effects to explore whether these effects were mediated by angiogenesis inhibition or by other “off-target” effects on the tumor microenvironment. Studies of sorafenib comprised the majority (58 of the 71) of the research articles reviewed. Potentially beneficial effects on anti-tumor immunity may result from increased M1 polarization of macrophages and stimulation of CD8 T cell function. On the other hand, high dosage of the kinase inhibitors in pre-clinical models and hypoxia associated with angiogenesis may contribute to immune suppression in the tumor microenvironment. Sorafenib and other multikinase inhibitors may promote anti-tumor immunity through modulation of multiple immune cell types as well as the tumor microenvironment. The optimal immune modulatory dosage should be defined to facilitate design of future combination regimens.

Simple Summary Immunotherapy is currently the backbone of new drug treatments for many cancer patients. CXC chemokine ligand 13 (CXCL13) is an important factor involved in recruiting immune cells that express CXC chemokine receptor type 5 (CXCR5) in the tumor microenvironment and serves as a key molecular determinant of tertiary lymphoid structure (TLS) formation. An increasing number of studies have identified the influence of CXCL13 on prognosis in patients with cancer, regardless of the use of immunotherapy treatment. However, no comprehensive reviews of the role of CXCL13 in cancer immunotherapy have been published to date. This review aims to provide an overview of the CXCL13/CXCR5 signaling axis to summarize its mechanisms of action in cancer cells and lymphocytes, in addition to effects on immunity and cancer pathobiology, and its potential as a biomarker for the response to cancer immunotherapy. Abstract Immune checkpoint inhibitors (ICIs), including antibodies that target programmed cell death protein 1 (PD-1), programmed death-ligand 1 (PD-L1), or cytotoxic T lymphocyte antigen 4 (CTLA4), represent some of the most important breakthroughs in new drug development for oncology therapy from the past decade. CXC chemokine ligand 13 (CXCL13) exclusively binds CXC chemokine receptor type 5 (CXCR5), which plays a critical role in immune cell recruitment and activation and the regulation of the adaptive immune response. CXCL13 is a key molecular determinant of the formation of tertiary lymphoid structures (TLSs), which are organized aggregates of T, B, and dendritic cells that participate in the adaptive antitumor immune response. CXCL13 may also serve as a prognostic and predictive factor, and the role played by CXCL13 in some ICI-responsive tumor types has gained intense interest. This review discusses how CXCL13/CXCR5 signaling modulates cancer and immune cells to promote lymphocyte infiltration, activation by tumor antigens, and differentiation to increase the antitumor immune response. We also summarize recent preclinical and clinical evidence regarding the ICI-therapeutic implications of targeting the CXCL13/CXCR5 axis and discuss the potential role of this signaling pathway in cancer immunotherapy.

Internal tandem duplication of FLT3 juxtamembrane domain (FLT3-ITD)-positive acute myeloid leukemia (AML) leads to poor clinical outcomes after chemotherapy. We aimed to establish a cytarabine-resistant line from FLT3-ITD-positive MV4-11 (MV4-11-P) cells and examine the development of resistance. The FLT3-ITD mutation was retained in MV4-11-R, however, the protein was underglycosylated and less phosphorylated in these cells. Moreover, the phosphorylation of ERK1/2, Akt, MEK1/2 and p53 increased in MV4-11-R. The levels of Mcl-1 and p53 proteins were also elevated in MV4-11-R. A p53 D281G mutant emerged in MV4-11-R, in addition to the pre-existing R248W mutation. MV4-11-P and MV4-11-R showed similar sensitivity to cabozantinib, sorafenib, and MK2206, whereas MV4-11-R showed resistance to CI-1040 and idarubicin. MV4-11-R resistance may be associated with inhibition of Akt phosphorylation, but not ERK phosphorylation, after exposure to these drugs. The multi-kinase inhibitor cabozantinib inhibited FLT3-ITD signaling in MV4-11-R cells and MV4-11-R-derived tumors in mice. Cabozantinib effectively inhibited tumor growth and prolonged survival time in mice bearing MV4-11-R-derived tumors. Together, our findings suggest that Mcl-1 and Akt phosphorylation are potential therapeutic targets for p53 mutants and that cabozantinib is an effective treatment in cytarabine-resistant FLT3-ITD-positive AML.

Liver cancer is one of the most common cancers worldwide, 75% of which are hepatocellular carcinoma (HCC). Generally, chronic inflammation and animmunosuppressive tumor micro environment are steadily activated in HCC. Although the US Food and Drug Administration (FDA) has approved immune checkpoint inhibitors (ICIs) for use as a clinically advanced HCC treatment,their efficacy in the clinical setting is not satisfactory. Moreover, only a small fraction of antibody reaches the target via systemic circulation due to neutralization of antibodies and off-target delivery. To enhance the localized effects of ICIs, iron oxide nanoparticles (≈10 nm) are conjugated with an antiprogrammed death-1 (anti-PD1) antibody and introduced the ironized antibodies into orthotopic HCC tumors via the systemic circulation. When mice are sacrificed 13 days after the final treatment, mice treated with ironizedanti-PD1 significantly regulate tumor-infiltrating leukocytes (TILs), particularly amplifying T-cell functions and recruiting M1 macrophages. More importantly,biochemical indices indicate that mice treated with ironized anti-PD1 recover liver function. This work presents iron oxide nanoparticles integrated with an anti-PD1 antibody that immunomodulates the immunosuppressive tumor micro environment to generate synergistic effects that achieve tumor inhibition and immune response activation in the context of HCC therapy. Refereed/Peer-reviewed

The family of microRNAs (miRNAs) not only plays an important role in gene regulation but is also useful for the diagnosis of diseases. A reliable method with high sensitivity may allow researchers to detect slight fluctuations in ultra-trace amounts of miRNA. In this study, we propose a sensitive imaging method for the direct probing of miR-10b (miR-10b-3p, also called miR-10b*) and its target (HOXD10 mRNA) in fixed cells based on the specific recognition of molecular beacons combined with highly inclined and laminated optical sheet (HILO) fluorescence microscopy. The designed dye-quencher-labelled molecular beacons offer excellent efficiencies of fluorescence resonance energy transfer that allow us to detect miRNA and the target mRNA simultaneously in hepatocellular carcinoma cells using HILO fluorescence microscopy. Not only can the basal trace amount of miRNA be observed in each individual cell, but the obtained images also indicate that this method is useful for monitoring the fluctuations in ultra-trace amounts of miRNA when the cells are transfected with a miRNA precursor or a miRNA inhibitor (anti-miR). Furthermore, a reasonable causal relation between the miR-10b and HOXD10 expression levels was observed in miR-10b* precursor-transfected cells and miR-10b* inhibitor-transfected cells. The trends of the miRNA alterations obtained using HILO microscopy completely matched the RT-qPCR data and showed remarkable reproducibility (the coefficient of variation [CV] = 0.86%) and sensitivity (

Internal tandem duplication of FLT3 juxtamembrane domain (FLT3-ITD)-positive acute myeloid leukemia (AML) leads to poor clinical outcomes after chemotherapy. We aimed to establish a cytarabine-resistant line from FLT3-ITD-positive MV4-11 (MV4-11-P) cells and examine the development of resistance. The FLT3-ITD mutation was retained in MV4-11-R; however, the protein was underglycosylated and less phosphorylated in these cells. Moreover, the phosphorylation of ERK1/2, Akt, MEK1/2 and p53 increased in MV4-11-R. The levels of Mcl-1 and p53 proteins were also elevated in MV4-11-R. A p53 D281G mutant emerged in MV4-11-R, in addition to the pre-existing R248W mutation. MV4-11-P and MV4-11-R showed similar sensitivity to cabozantinib, sorafenib, and MK2206, whereas MV4-11-R showed resistance to CI-1040 and idarubicin. MV4-11-R resistance may be associated with inhibition of Akt phosphorylation, but not ERK phosphorylation, after exposure to these drugs. The multi-kinase inhibitor cabozantinib inhibited FLT3-ITD signaling in MV4-11-R cells and MV4-11-R-derived tumors in mice. Cabozantinib effectively inhibited tumor growth and prolonged survival time in mice bearing MV4-11-R-derived tumors. Together, our findings suggest that Mcl-1 and Akt phosphorylation are potential therapeutic targets for p53 mutants and that cabozantinib is an effective treatment in cytarabine-resistant FLT3-ITD-positive AML.

// Da-Liang Ou 1, 2 , Song-Kun Shyue 3 , Liang-In Lin 4 , Zi-Rui Feng 2, 5 , Jun-Yang Liou 6 , Hsiang-Hsuan Fan 2, 5 , Bin-Shyun Lee 2, 5 , Chiun Hsu 1, 5, 7 , Ann-Lii Cheng 1, 5, 7, 8 1 Graduate Institute of Oncology, College of Medicine, National Taiwan University, Taipei, Taiwan 2 National Center of Excellence for Clinical Trial and Research, National Taiwan University Hospital, Taipei, Taiwan 3 Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan 4 Graduate Institute of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan 5 Department of Oncology, National Taiwan University Hospital, Taipei, Taiwan 6 Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan 7 Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan 8 Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taiwan Correspondence to: Chiun Hsu, e-mail: hsuchiun@gmail.com Keywords: GADD45γ, hepatocellular carcinoma (HCC), sorafenib, CCAAT/enhancer binding protein (C/EBP), survivin Received: February 26, 2015 Accepted: June 19, 2015 Published: June 29, 2015 ABSTRACT Growth arrest DNA damage-inducible gene 45 (GADD45) family proteins play a crucial role in regulating cellular stress responses and apoptosis. The present study explored the prognostic and predictive role of GADD45γ in hepatocellular carcinoma (HCC) treatment. GADD45γ expression in HCC cells was examined using quantitative reverse transcription-PCR (qRT-PCR) and Western blotting. The control of GADD45γ transcription was examined using a luciferase reporter assay and chromatin immunoprecipitation. The in vivo induction of GADD45γ was performed using adenoviral transfer. The expression of GADD45γ in HCC tumor tissues from patients who had undergone curative resection was measured using qRT-PCR. Sorafenib induced expression of GADD45γ mRNA and protein, independent of its RAF kinase inhibitor activity. GADD45γ induction was more prominent in sorafenib-sensitive HCC cells (Huh-7 and HepG2, IC 50 6–7 μM) than in sorafenib-resistant HCC cells (Hep3B, Huh-7R, and HepG2R, IC 50 12–15 μM). Overexpression of GADD45γ reversed sorafenib resistance in vitro and in vivo , whereas GADD45γ expression knockdown by using siRNA partially abrogated the proapoptotic effects of sorafenib on sorafenib-sensitive cells. Overexpression of survivin in HCC cells abolished the antitumor enhancement between GADD45γ overexpression and sorafenib treatment, suggesting that survivin is a crucial mediator of antitumor effects of GADD45γ. GADD45γ expression decreased in tumors from patients with HCC who had undergone curative surgery, and low GADD45γ expression was an independent prognostic factor for poor survival, in addition to old age and vascular invasion. The preceding data indicate that GADD45γ suppression is a poor prognostic factor in patients with HCC and may help predict sorafenib efficacy in HCC.

Background Lenalidomide has immunomodulatory and anti-angiogenic effects and showed moderate anti-tumour efficacy in patients with. advanced hepatocellular carcinoma (HCC) Aim To explore potential biomarkers of lenalidomide efficacy as second-line therapy for HCC. Methods Eligible patients were diagnosed with advanced HCC, documented progression on sorafenib, and Child-Pugh class A liver function. Patients received 25 mg/day lenalidomide orally on days 1-21 every 4 weeks. The primary endpoint was 6 month progression-free survival rate. Early α-fetoprotein response was defined as a > 20% decline of α-fetoprotein levels from baseline within the first 4 weeks of treatment. Vascular response, evaluated using dynamic contrast-enhanced magnetic resonance imaging, was defined as a > 40% decline in Ktrans after 2 weeks of treatment. The percentage of peripheral blood lymphocyte subsets were also analysed. Results Fifty-five patients were enrolled. The response rate was 13%, and the disease-control rate was 53%. The 6 month progression-free survival rate was 9.1%. The median progression-free and overall survival was 1.8 months and 8.9 months respectively. Early α-fetoprotein response was significantly associated with higher disease-control rate (76% vs 22%, P = .001) and longer progression-free survival (P = .020). Vascular response was not associated with any treatment outcomes. Patients with a high pre-treatment B cell percentage were more likely to have disease control (70% vs 36%, P = .010) and exhibited longer progression-free survival (P < .001) and overall survival (P = .042). Conclusions Lenalidomide exhibited moderate activity as second-line therapy for advanced HCC. Its immunomodulatory effects should be further explored (www.clinicaltrials.gov NCT01545804).

Aberrant histone methylation is a frequent event during tumor development and progression. KMT1E (also known as SETDB1) is a histone H3K9 methyltransferase that contributes to epigenetic silencing of both oncogenes and tumor suppressor genes in cancer cells. In this report, we demonstrate that KMT1E acts as a metastasis suppressor that is strongly downregulated in highly metastatic lung cancer cells. Restoring KMT1E expression in this setting suppressed filopodia formation, migration, and invasive behavior. Conversely, loss of KMT1E in lung cancer cells with limited metastatic potential promoted migration in vitro and restored metastatic prowess in vivo. Mechanistic investigations indicated that KMT1E cooperates with the TGFβ-regulated complex SMAD2/3 to repress metastasis through ANXA2. Together, our findings defined an essential role for the KMT1E/SMAD2/3 repressor complex in TGFβ-mediated lung cancer metastasis. Cancer Res; 74(24); 7333–43. ©2014 AACR.

Background and Aim The immune modulatory drug lenalidomide has shown promising anti-tumor activity in a clinical trial of patients with advanced hepatocellular carcinoma (HCC). The present study explored whether lenalidomide can enhance the anti-tumor activity of sorafenib, the standard molecular targeted therapy for HCC. Methods The anti-tumor efficacy of single-agent or combination treatment was measured by change in tumor volume and animal survival using an orthotopic liver cancer model. Distribution of T-cell subpopulations in tumor-infiltrating lymphocytes (TILs) and splenocytes derived from tumor-implanted mice was measured by flow cytometry. Depletion of relevant T-cell subpopulations or cytokines was done by co-administration of relevant antibodies with study drug treatment. Tumor cell apoptosis and tumor angiogenesis were measured by transferase deoxytidyl uridine end labeling assay and immunohistochemical study, respectively. Results Combination of sorafenib and lenalidomide produced significant synergistic anti-tumor efficacy in terms of tumor growth delay and animal survival. This synergistic effect was associated with a significant increase in interferon-γ expressing CD8+ lymphocytes in TILs and a significantly higher number of granzyme- or perforin-expressing CD8+ T cells, compared with vehicle- or single-agent treatment groups. Combination treatment significantly increased apoptotic tumor cells and vascular normalization in tumor tissue. The synergistic anti-tumor effect was abolished after CD8 depletion. Conclusions Lenalidomide can enhance the anti-tumor effects of sorafenib in HCC through its immune modulatory effects, and CD8+ TILs play an important role in the anti-tumor synergism.

Background: Sorafenib is the only drug approved for the treatment of hepatocellular carcinoma (HCC). The bioenergetic propensity of cancer cells has been correlated to anticancer drug resistance, but such correlation is unclear in sorafenib resistance of HCC. Methods: Six sorafenib-naive HCC cell lines and one sorafenib-resistant HCC cell line (Huh-7R; derived from sorafenib-sensitive Huh-7) were used. The bioenergetic propensity was calculated by measurement of lactate in the presence or absence of oligomycin. Dichloroacetate (DCA), a pyruvate dehydrogenase kinase (PDK) inhibitor, and siRNA of hexokinase 2 (HK2) were used to target relevant pathways of cancer metabolism. Cell viability, mitochondrial membrane potential, and sub-G1 fraction were measured for in vitro efficacy. Reactive oxygen species (ROS), adenosine triphosphate (ATP) and glucose uptake were also measured. A subcutaneous xenograft mouse model was used for in vivo efficacy. Results: The bioenergetic propensity for using glycolysis correlated with decreased sorafenib sensitivity (R2=0.9067, among sorafenib-naive cell lines; P=0.003, compared between Huh-7 and Huh-7 R). DCA reduced lactate production and increased ROS and ATP, indicating activation of oxidative phosphorylation (OXPHOS). DCA markedly sensitised sorafenib-resistant HCC cells to sorafenib-induced apoptosis (sub-G1 (combination vs sorafenib): Hep3B, 65.4±8.4% vs 13±2.9% Huh-7 R, 25.3± 5.7% vs 4.3±1.5% each P

Background: Internal tandem duplication in the juxtamembranal region of FLT3 gene (FLT3-ITD) is one of the most common mutations in acute myeloid leukemia (AML), resulting in constitutive activation of FLT3 signaling pathway. Therefore FLT3 have been proved to be as a useful target for AML treatment. Previously, we demonstrated that cabozantinib, an oral multi-target tyrosine kinase inhibitor (TKI), could selectively cytotoxic to AML cells with FLT3-ITD (MV4-11 and Molm13). Recently, cabozantinib was reported to be well tolerated in AML patients with FLT3-ITD and potentially be useful in the treatment of AML with FLT3-ITD. However, it is known that TKI-resistance in AML often cause higher relapse rates and lower survival rates. In order to study the drug resistance mechanism, we established cabozantinib-resistant cell lines from MV4-11 and Molm13 cells, after gradual escalating concentration of cabozantinib incubation, with increasing IC50 from 9.5nM to 1.5μM and from 1.06nM to 473.36nM, respectively. The cabozantinib-resistance cell lines were named MV4-11 XR and Molm-13 XR, respectively. Aims: To elucidate the mechanism of survival advantage of cabozantinib-resistance of MV4-11-XR and Molm13-XR. Materials and Methods : The differential expression genes (DEGs) were examined using RNA-seq (Illumina NextSeq-500). Metascape recourse and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analyses were performed to predict the biological functions of DEGs. Quantitative PCR (Q-PCR) were used to validate the RNA-seq results. The extracellular acidification rate (ECAR) was measured using Seahorse bio-analyzer. In addition, to investigate the mitochondrial metabolism, analyses of oxygen consumption rate (OCR), glucose uptake, GAPDH activity, lactate production, ATP content were performed. Results: The gene expression profile in MV4-11 cells and Molm13 cells were used as baselines to establish the up- or down-regulated genes in MV4-11-XR and Molm13-XR cells, respectively. The FPKM were estimated with the selection criteria of q value1 or Conclusion: Our study highlights that alteration of metabolic pathways may contribute cabozantinib resistance. We suggest that targeting these pathways may be a viable strategy to overcome cabozantinib resistance. Disclosures No relevant conflicts of interest to declare.

Background: pyrvinium pamoate is an FDA-approved anthelmintic, and was incidentally found to have significant anti-cancer activity with various molecular mechanisms. However, the anticancer effects and mechanisms of pyrvinium against AML cells are still not clear. Internal tandem duplication in the juxtamembranal region of FLT3 gene (FLT3-ITD) is one of the most common mutations in acute myeloid leukemia (AML), resulting in constitutive activation of FLT3 signaling pathway. Therefore, FLT3 have thought to be as a target for AML treatment. Previously, we demonstrated that cabozantinib, an oral multi-target tyrosine kinase inhibitor, could selectively cytotoxic in AML cells with FLT3-ITD. However, drug resistance developed after gradual escalating concentration of cabozantinib incubation of the FLT3-ITD-harboring Molm13 cells, with IC50 increased from 1.06nM of parental Molm13 cells to 473.36nM of the resistant Molm13-XR cells. Interestingly, the IC50 of pyrvinium pamoate on Molm13 and Molm13-XR cells were 6.26nM and 5.31nM, respectively, suggesting that pyrvinium could overcome cabozantinib-resistance in AML cells. Aims: To investigate the molecular mechanism of pyrvinium pamoate in both Molm13 and Molm13-XR cells. Materials and Methods: Sanger's sequencing and pyrosequencer were used to characterize the recurrent mutations in Molm13-XR cells. Phospho-kinase array and Western blotting were used to investigate and confirm the molecules regarding to several signaling pathways and apoptosis, respectively. The oxygen consumption rate (OCR), a key parameter reflecting oxidative phosphorylation, was measured using Seahorse bio-analyzer. In addition, mitochondrial function, Wnt signaling pathway and autophagy signaling pathway were also evaluated. Mouse xenograft experiments were performed with subcutaneously inoculating leukemia cells to BALB/c athymic mice aged 6-8 weeks. The protocol for the xenograft experiments was approved by the IACUC, National Taiwan University. Results: Molm13-XR cells had similar FLT3-ITD burden as Molm13 cells, but with increased FLT3D835Y mutations from 3% to 35%, suggesting the selection of FLT3-ITD/FLT3D835Y clone after cabozantinib resistance developed. By using human phospho-kinase array, increased phospho-STAT5a/b, phospho-Akt, phosph-ERK, phospho-CREB and phospho-GSK3α/β were noted in Molm13-XR cells. Western blotting revealed increased MCL-1 in Molm13-XR cells. We found that pyrvinium could enter Molm13-XR cells and localize on mitochondria and then decrease mitochondria basal oxidative consumption rate, decrease ATP production and increase reactive oxygen species (ROS) level in a dose-dependent manner. In addition, pyrvinium decreased phospho-STAT5, phosph-ERK, phospho-AKT and pohospho-GSK3β, those were increased when cabozantinib-resistance. Significantly, pyrvinium had no effect on these signaling pathways in Molm13 cells. In mouse xenograft model, pyrvinium significantly inhibited Molm13 and Molm13-XR tumor growth at a dosage of 0.5mg/kg and showed longer survival rate. Conclusion: In this study, we discovered that pyrvinium overcome cabozantinib-resistance of FLT3-ITD AML cells at least partially via modulation of both mitochondrial function and multiple pivotal signal transduction pathways. The dual functions of pyrvinium could be potentially applicable for further clinical use in the future. Disclosures No relevant conflicts of interest to declare.

Markers that could accurately predict responses to the general kinase inhibitor sorafenib are needed to better leverage its clinical applications. In this study, we examined a hypothesized role in the drug response for the growth arrest DNA damage-inducible gene 45β (GADD45β), which is commonly underexpressed in hepatocellular carcinoma (HCC) where sorafenib may offer an important new therapeutic option. The anticancer activity of sorafenib-induced GADD45β expression was tested in a panel of HCC cell lines and xenograft models. We found that GADD45β mRNA and protein expression were induced relatively more prominently in HCC cells that were biologically sensitive to sorafenib treatment. GADD45β induction was not found after treatment with either the mitogen-activated protein kinase–extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor U0126 or the Raf inhibitor ZM336372, suggesting that GADD45β induction by sorafenib was independent of Raf/MEK/ERK signaling activity. However, c-Jun NH2-terminal kinase (JNK) kinase activation occurred preferentially in sorafenib-sensitive cells. Small interfering RNA–mediated knockdown of GADD45βor JNK kinase limited the proapoptotic effects of sorafenib in sorafenib-sensitive cells. We defined the −339/−267 region in the GADD45β promoter containing activator protein-1 and SP1-binding sites as a crucial region for GADD45β induction by sorafenib. Together, our findings suggest that GADD45β induction contributes to sorafenib-induced apoptosis in HCC cells, prompting further studies to validate its potential value in predicting sorafenib efficacy. Cancer Res; 70(22); 9309–18. ©2010 AACR.

Hypermethylation of the distal CEBPA promoter region has been reported to result in the downregulation of CEBPA expression in several malignancies. However, the clinical implication of CEBPA hypermethylation in acute myeloid leukemia (AML) remains unclear. To investigate the correlation between CEBPA hypermethylation and clinical features in AML, quantitative MassARRAY analyses for CEBPA methylation status were performed on a cohort of 193 patients. High CEBPA methylation group (CEBPA(high-meth), n=28) and low methylation group (CEBPA(low-meth), n=165) were defined by using two-way hierarchical clustering. With a median follow-up of 48 months, among the 125 patients receiving standard induction therapy, CEBPA(high-meth) was associated with better treatment response (complete remission rate 93.3% versus 73.6%, P=0.116). In patients with normal karyotype and without CEBPA and NPM1 mutations, the CEBPA(high-meth) had longer overall survival (OS) than the CEBPA(low-meth) (P=0.028). Multivariate analysis further supported that the CEBPA methylation was an independent prognostic factor for disease free-survival (hazard ratio=0.416; 95% confidence interval, 0.223-0.777, P=0.006) and OS (hazard ratio=0.406; 95% confidence interval, 0.166-0.996, P=0.050). We conclude that CEBPA methylation status is a useful prognostic biomarker for AML patients.