Targeted immune cell therapy for hepatocellular carcinoma using expanded liver mononuclear cell-derived natural killer cells

Natural killer (NK) cells are a promising cellular therapy for T cell-refractory cancers but are frequently deficient or dysfunctional in patients with hepatocellular carcinoma (HCC). In the present study, we explored a novel therapy for HCC using NK cells derived from donor liver graft perfusate. These liver-derived NK cells, named LMNC-NK cells, are more abundant in liver mononuclear cells (LMNCs) than in peripheral blood mononuclear cells (PBMCs) from the same donor. We developed a method to expand LMNC-NK cells by 33.8±54.4-fold, enhancing their cytotoxic properties and cytokine production, including granzyme B, CD107a, TNF-α, and IFN-γ. These cells also showed an increased expression of cytotoxicity receptors. An RNA-seq analysis revealed considerable differences in gene expression between LMNC-NK and PBMC-NK cells, with 453 genes upregulated and 449 downregulated in LMNC-NK cells. These genes are involved in the mitogen-activated protein kinase cascade and cell differentiation, explaining the increased activity of LMNC-NK cells. Quantitative reverse transcription polymerase chain reaction confirmed the significant upregulation of TLR6, KIT, MMP14, IRF8, TCF7, FCERIG, LEF1, NLRp3, and IL16 in LMNC-NK cells. LMNC-NK cells effectively eliminated HepG-2-Luc cells in vitro, and in an orthotopic murine model of HCC, they exhibited a potent anti-tumor effect, outperforming PBMC-NK cells. The expression of the activation marker CD69+ in LMNC-NK cells was also significantly higher among tumor-infiltrating lymphocytes compared to PBMC-NK cells. Our research suggests that the adoptive transfer of LMNC-NK cells could be a promising treatment for HCC, offering a novel and effective source of NK cells with superior cytotoxic functions.

PAX5 functions as a tumor suppressor by RB-E2F-mediated cell cycle arrest in Kaposi sarcoma-associated herpesvirus-infected primary effusion lymphoma

Primary effusion lymphoma (PEL) is a malignant B-cell lymphoma attributable to Kaposi sarcoma-associated herpesvirus (KSHV) infection. PEL is characterized by invasive behavior, showing recurrent effusions in body cavities. The clinical outcome and typical prognosis in patients with PEL are poor and potentially lethal. Clarification of the pathogenesis in PEL is urgently needed in order to develop novel therapies. PEL cells generally lack B-cell surface markers, and we therefore hypothesized that the B-cell transcription factor, PAX5, would be down-regulated in PEL. The expression of PAX5 is detected from the pro-B to the mature B-cell stage and is indispensable for the differentiation of B-cells. PAX5 was silenced in PEL cells via its promoter methylation. Up-regulation of PAX5 induced several genes coding for B-cell surface marker mRNA, but not protein level. PAX5 inhibited cell growth via G1 cell cycle arrest. PAX5 bound to RB and increased its protein expression. RB/E2F-regulated genes were significantly down-regulated in microarray analysis and PCR experiments. To elucidate the in vivo role of PAX5, we examined the restoration of PAX5 in a PEL mouse model. The ascites volume and organ invasions were significantly suppressed by PAX5 restoration. Reduction of PAX5 has played a crucial role in the oncogenesis of PEL, and PAX5 is a tumor suppressor in PEL. Targeting PAX5 could represent a novel therapeutic strategy for patients with PEL.

A live single-cell reporter system reveals drug-induced plasticity of a cancer stem cell-like population in cholangiocarcinoma

Cancer stem cells (CSC) play an important role in carcinogenesis and are acknowledged to be responsible for chemoresistance in cholangiocarcinoma (CCA). Studying CCA CSC has been challenging, due to lack of consensus CSC markers, and to their plastic nature. Since dual expression of the core pluripotent factors SOX2/OCT4 has been shown to correlate with poor outcome in CCA patients, we selected the SOX2/OCT4 activating short half-life GFP-based live reporter (SORE6-dsCopGFP) to study CSC dynamics at the single-cell level. Transduction of five human CCA cell lines resulted in the expression of 1.8-13.1% GFP-positive (SORE6POS) cells. By live imaging, we found that SORE6POS CCA cells possess self-renewal capacity and that they can be induced to differentiate. Significantly, the SORE6POS cells were highly tumorigenic, both in vitro and in vivo, thus implicating the characteristics of primary CSCs. When we then analyzed for selected CSC-related markers, we found that the majority of both CD133+/CD44+, and CD133+/LGR5+ CCA cells were SORE6POS cells. Exposing transduced cells to standard CCA chemotherapy revealed higher growth rate inhibition at 50% (GR50s) for SORE6POS cells compared to GFP-negative (SORE6NEG) ones indicating that these CSC-like cells were more resistant to the treatment. Moreover, the chemotherapy induced SORE6POS from SORE6NEG cells, while retaining the existing SORE6POS population. Finally, treatment of transduced cells with CDK4/6 inhibitors in vitro for 3 days resulted in a lowered CSC number in the culture. Thus, applying a live reporter system allowed us to elucidate the stem cell diversity and drug-induced plasticity of CCA CSCs. These findings have clear implications for future management of such patients.

Facilitating cholangiocarcinoma inhibition by targeting CD47

Immune evasion is one of the mechanisms by which cancer cells acquire immunity during cancer development and progression. One of these is the increased expression of cluster of differentiation 47 (CD47), a transmembrane glycoprotein that protects cells from phagocytic elimination. The interaction between CD47 and signal regulatory protein alpha (SIRPα) on macrophages alleviates the phagocytic signal. The present group previously reported high CD47 expression in cholangiocarcinoma (CCA), a major health problem in Thailand and East Asia, and that blocking CD47 using anti-CD47 antibodies promoted the removal of CCA. However, the mechanism through which CD47 inhibition attenuates CCA growth remains unclear. This study explored the clinical significance of targeting CD47 in CCA. Expression levels of CD47 and the macrophage marker CD68 were determined in CCA tissues by immunohistochemistry and correlated with clinical parameters. The role of CD47 in CCA cells was established using CD47-deficient KKU-213A CCA clones in vitro and in vivo. The results showed that CD47 was highly expressed in CCA tissues and significantly correlated with lymph node metastasis (P = 0.038). Moderate-to-dense CD68-positive infiltrating cells in CCA tissues were significantly associated with shorter survival of patients (P = 0.019) and were an independent prognostic factor of CCA patients as determined by the Cox proportional hazard model (hazard ratio, 2.040; 95 % confidence interval, 1.109-3.752; P = 0.022). Three CD47-deficient KKU-213A clones (#19, #23, and #28) were generated. The elimination of CD47 did not affect cell proliferation but increased monocyte-derived macrophage-mediated phagocytosis in vitro. Decreased tumor weights and volumes were observed in mice injected with CD47-deficient CCA clones. This revealed a significant role for CD47 in CCA, with a focus on protecting cancer cells from macrophage phagocytosis.

Evaluating the Use of Sacran, a Polysaccharide Isolated from Aphanothece sacrum, as a Possible Microbicide for Preventing HIV-1 Infection

Since combination antiretroviral therapy (cART) was introduced to treat human immunodeficiency virus type-1 (HIV-1)/acquired immunodeficiency syndrome (AIDS), the AIDS mortality rate has markedly decreased, and convalescence in individuals with HIV has improved drastically. However, sexual transmission has made HIV-1 a global epidemic. Sacran is a megamolecular polysaccharide extracted from cyanobacterium Aphanothece sacrum that exhibits numerous desirable characteristics for transdermic applications, such as safety as a biomaterial, a high moisture retention effect, the ability to form a film and hydrogel, and an anti-inflammatory effect. In this study, we evaluated the anti-HIV-1 effects in sacran as a barrier to HIV-1 transmission. Sacran inhibited HIV-1 infection and envelope-dependent cell-to-cell fusion. Moreover, we used a Transwell assay to confirm that sacran inhibited viral diffusion and captured viruses. The synergistic effects of sacran and other anti-HIV infection drugs were also evaluated. HIV-1 infections can be reduced through the synergistic effects of sacran and anti-HIV-1 drugs. Our study suggests using sacran gel to provide protection against HIV-1 transmission.

Augmented Global Protein Acetylation Diminishes Cell Growth and Migration of Cholangiocarcinoma Cells

We have previously shown that the overexpression of acetyl-CoA carboxylase 1 (ACC1) was associated with the poor prognosis of cholangiocarcinoma (CCA) patients, and suppression of its expression in CCA cell lines deteriorated cell growth. The present study explored the mechanism by which ACC1 inhibition affects global protein acetylation, using genetic knockdown and pharmacological inhibition with an ACC1 inhibitor ND-646 as models. Both ACC1 knockdown and ACC1-inhibitor-treated cells displayed the hyperacetylation of proteins, accompanied by impaired growth and migration. The immunoprecipitation of hyperacetylated proteins using the anti-acetylated lysine antibody, followed by tandem mass spectrometry, identified three potential verification candidates, namely POTE ankyrin domain family member E, peroxisomal biogenesis factor 1, and heat shock protein 90 beta (HSP90B). HSP90 acetylation was the candidate selected for the verification of protein acetylation. To establish the effects of protein hyperacetylation, treatment with suberoylanilide hydroxamic acid (SAHA), a lysine deacetylase inhibitor, was conducted, and this served as an independent model. Decreased tumor growth but increased acetylated protein levels were observed in ACC1-KD xenograft tumors. Hyperacetylated-alleviated cell growth and migration were consistently observed in the SAHA-treated models. The molecular linkage between protein hyperacetylation and the AKT/GSK3β/Snail pathway was demonstrated. This study highlighted the importance of protein acetylation in CCA progression, suggesting that ACC1 and KDAC are potential targets for CCA treatment.

Trastuzumab, a monoclonal anti-HER2 antibody modulates cytotoxicity against cholangiocarcinoma via multiple mechanisms

Cholangiocarcinoma (CCA) is an aggressive and fatal cancer. The prognosis is very poor and no optimal chemotherapy has been established. Human epidermal growth factor receptor 2 (HER2, neu, and erbB2) is highly-expressed in breast cancer and is expressed in many other tumors but poorly expressed in CCA. The anti-HER2 antibody, trastuzumab, has been used for the treatment of HER2-positive breast and gastric cancer. In this study, we examined the surface expression of HER2 on seven Thai liver-fluke-associated CCA cell lines by flow cytometry, and found all of these CCA cells were weakly positive for HER2. MTT assay revealed that trastuzumab directly suppressed the growth of CCA. By using FcR-bearing recombinant Jurkat T-cell-expressing firefly luciferase gene under the control of NFAT response elements, we defined the activities of antibody-dependent cytotoxicity (ADCC) and antibody-dependent cell phagocytosis (ADCP). ADCC was confirmed by using expanded NK cells. ADCP was confirmed by using mouse peritoneal macrophages and human monocyte-derived macrophages as effector cells. Rabbit serum was administered to test the complement-dependent cytotoxicity (CDC) activity of trastuzumab. Finally, we evaluated the efficacy of trastuzumab in in vivo patient-derived cell xenograft and patient-derived xenograft (PDX) models. Our results showed that a distinct population of CCA (liver-fluke-associated CCA) expressed HER2. Trastuzumab demonstrated a potent inhibitory effect on even HER2 weakly positive CCA both in vitro and in vivo via multiple mechanisms. Thus, HER2 is a promising target in anti-CCA therapy, and trastuzumab can be considered a promising antibody immunotherapy agent for the treatment of CCA.

Anti-Tumor and Chemosensitizing Effects of the CDK Inhibitor Dinaciclib on Cholangiocarcinoma In Vitro and In Vivo

BACKGROUND/AIM

Cholangiocarcinoma (CCA) is a highly aggressive disease. Most of CCA patients are diagnosed in an advanced stage of the disease, when it is unresectable and there is chemoresistance, resulting in poor prognosis. However, effective therapeutic regimens and molecular targets for CCA remain poor. Cyclin-dependent kinases (CDKs) are key regulatory enzymes in cell cycle progression. Aberrant CDK activation is a hallmark of cancer. Dinaciclib is a small molecule inhibitor of multiple CDKs, currently under clinical evaluation for treating advanced malignancies. The efficacy of anti-tumor activity of dinaciclib against chemotherapy resistant CCA cells was examined in vitro and in vivo.

MATERIALS AND METHODS

In this study, the effect of dinaciclib on growth and cell cycle in CCA cell lines were determined using the MTT assay and cell cycle analysis. The anti-tumor activity of dinaciclib was investigated in CCA-inoculated mice. In addition, the chemosensitizing effect of dinaciclib was investigated in gemcitabine-treated CCA cell lines.

RESULTS

Dinaciclib significantly suppressed cell proliferation, induced G1/S phase cell cycle arrest and apoptosis of CCA cell lines. It significantly suppressed the growth of CCA cells in xenograft mouse models. We also found that dinaciclib significantly inhibited the growth of gemcitabine-resistant CCA cell lines (KKU-213A-GemR and KKU-100-GemR). Furthermore, dinaciclib significantly enhanced the anti-tumor activity of gemcitabine in CCA cell lines.

CONCLUSION

Dinaciclib has the potential to be an effective therapeutic agent to control tumor cell growth of both parental and gemcitabine-resistant CCA cells.

Involvement of interleukin-1β in high glucose-activated proliferation of cholangiocarcinoma

Background

Diabetes mellitus (DM) is associated with the increased risk of development and the advancement of cholangiocarcinoma (CCA). High glucose levels were previously shown for upregulating interleukin-1β (IL-1β) in CCA cells with unclear functions. The present study, thus, aimed to investigate molecular mechanisms linking DM to CCA progression, with IL-1β hypothesized as a communicating cytokine.

Methods

CCA cells were cultured in media with normal (5.6 mM) or high (25 mM) glucose, resembling euglycemia and hyperglycemia, respectively. Expressions of IL-1β and IL-1 receptor (IL-1R) in CCA tissues from patients with and without DM were examined using immunohistochemistry. Functional analyses of IL-1β were performed using siRNA and recombinant human IL-1R antagonist (rhIL-1RA), in which Western blots investigated the knockdown efficacy. BALB/c Rag-2-/- Jak3-/- (BRJ) mice were implanted with CCA xenografts to investigate hyperglycemia's effects on CCA growth and the anti-tumor effects of IL-1RA.

Results

CCA tumors from patients with hyperglycemia showed significantly higher IL-1β expression than those from non-DM patients, while IL-1β was positively correlated with fasting blood glucose (FBG) levels. CCA cells cultured in high glucose showed increased IL-1β expression, resulting in increased proliferation rates. Suppressing IL-1β signaling by si-IL-1β or rhIL-1RA significantly reduced CCA cell proliferation in vitro. Anakinra, a synthetic IL-1RA, also exerted significant anti-tumor effects in vivo and significantly reversed the effects of hyperglycemia-induced growth in CCA xenografts.

Conclusions

IL-1β plays a crucial role in CCA progression in a high-glucose environment. Targeting IL-1β might, then, help improve therapeutic outcomes of CCA in patients with DM and hyperglycemia.

Establishment and characterization of TK-ALCL1: a novel NPM-ALK-positive anaplastic large-cell lymphoma cell line

TK-ALCL1, a novel anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALK+ ALCL) cell line, was established from the primary tumor site of a 59-year-old Japanese male patient. The immune profile of TK-ALCL1 corresponds to that seen typically in primary ALCL cells, i.e., positive for ALK, CD30, EMA, and CD4, but negative for CD2, CD3, CD5, CD8a, and EBV-related antigens. The rearrangement of the T cell receptor-gamma locus shows that TK-ALCL1 is clonally derived from T-lineage lymphoid cells. FISH and RT-PCR analysis revealed that TK-ALCL1 has the nucleophosmin (NPM)-ALK fusion transcript, which is typical for ALK+ ALCL cell lines. When TK-ALCL1 was subcutaneously inoculated into 6-week-old BALB/c Rag2-/-/Jak3-/- (BRJ) mice, it formed tumor masses within 4-6 weeks. Morphological, immunohistochemical, and molecular genetic investigations confirmed that the xenograft and the original ALCL tumor were identical. The ALK inhibitors Alectinib and Lorlatinib suppressed proliferation in a dose-dependent manner. Thus, TK-ALCL1 provides a useful in vitro and in vivo model for investigation of the biology of ALK+ ALCL and of novel therapeutic approaches targeting ALK.

Promising immunotherapeutic approaches for primary effusion lymphoma

Primary effusion lymphoma (PEL) is a large B-cell neoplasm usually presenting as a serious effusion in body cavities without detectable tumor masses. It is an AIDS-related non-Hodgkin's lymphoma (HL) with human herpes virus 8 (HHV8)/Kaposi sarcoma-associated herpes virus (KSHV) infection. A combination antiretroviral therapy (cART) prolongs the lifespan of AIDS and AIDS-related malignant lymphoma patients, but PEL continues to have a dismal prognosis. PEL showed disappointing outcomes with standard chemotherapy such as CHOP or CHOP-like regimens. A PEL status highlights the urgent need for new therapeutic approaches and treatment strategies and improve clinical outcomes. This review discusses the current knowledge and some recent clinical trials for PEL in the platform of immunotherapy as well as promising future immunotherapeutic approaches for PEL.

Liraglutide exhibits potential anti-tumor effects on the progression of intrahepatic cholangiocarcinoma, in vitro and in vivo

Glucagon-like peptide 1 receptor (GLP-1R) agonist is an emerging anti-diabetic medication whose effects on the risk and progression of cholangiocarcinoma (CCA) are controversial. This study aimed to elucidate the roles of GLP-1R and its agonists on intrahepatic CCA (iCCA) progression. Expressions of GLP-1R in iCCA tissues investigated by immunohistochemistry showed that GLP-1R expressions were significantly associated with poor histological grading (P = 0.027). iCCA cell lines, KKU-055 and KKU-213A, were treated with exendin-4 and liraglutide, GLP-1R agonists, and their effects on proliferation and migration were assessed. Exendin-4 and liraglutide did not affect CCA cell proliferation in vitro, but liraglutide significantly suppressed the migration of CCA cells, partly by inhibiting epithelial-mesenchymal transition. In contrast, liraglutide significantly reduced CCA tumor volumes and weights in xenografted mice (P = 0.046). GLP-1R appeared downregulated when CCA cells were treated with liraglutide in vitro and in vivo. In addition, liraglutide treatment significantly suppressed Akt and STAT3 signaling in CCA cells, by reducing their phosphorylation levels. These results suggested that liraglutide potentially slows down CCA progression, and further clinical investigation would benefit the treatment of CCA with diabetes mellitus.

Tri-specific killer engager: unleashing multi-synergic power against cancer

Cancer continues to be a global health concern, necessitating innovative solutions for treatment. Tri-specific killer engagers (TriKEs) have emerged as a promising class of immunotherapeutic agents, offering a multifaceted approach to cancer treatment. TriKEs simultaneously engage and activate natural killer (NK) cells while specifically targeting cancer cells, representing an outstanding advancement in immunotherapy. This review explores the generation and mechanisms of TriKEs, highlighting their advantages over other immunotherapies and discussing their potential impact on clinical trials and cancer treatment. TriKEs are composed of three distinct domains, primarily antibody-derived building blocks, linked together by short amino acid sequences. They incorporate critical elements, anti-cluster of differentiation 16 (CD16) and interleukin-15 (IL-15), which activate and enhance NK cell function, together with specific antibody to target each cancer. TriKEs exhibit remarkable potential in preclinical and early clinical studies across various cancer types, making them a versatile tool in cancer immunotherapy. Comparative analyses with other immunotherapies, such as chimeric antigen receptor-T (CAR-T) cell therapy, immune checkpoint inhibitors (ICIs), cytokine therapies, and monoclonal antibodies (mAbs), reveal the unique advantages of TriKEs. They offer a safer pathway for immunotherapy by targeting cancer cells without hyperactivating T cells, reducing off-target effects and complications. The future of TriKEs involves addressing challenges related to dosing, tumor-associated antigen (TAA) expression, and NK cell suppression. Researchers are exploring innovative dosing strategies, enhancing specificity through tumor-specific antigens (TSAs), and combining TriKEs with other therapies for increased efficacy.

Reprogramming of pyrimidine nucleotide metabolism supports vigorous cell proliferation of normal and malignant T cells

ABSTRACT

Adult T-cell leukemia/lymphoma (ATL) is triggered by infection with human T-cell lymphotropic virus-1 (HTLV-1). Here, we describe the reprogramming of pyrimidine biosynthesis in both normal T cells and ATL cells through regulation of uridine-cytidine kinase 2 (UCK2), which supports vigorous proliferation. UCK2 catalyzes the monophosphorylation of cytidine/uridine and their analogues during pyrimidine biosynthesis and drug metabolism. We found that UCK2 was overexpressed aberrantly in HTLV-1-infected T cells but not in normal T cells. T-cell activation via T-cell receptor (TCR) signaling induced expression of UCK2 in normal T cells. Somatic alterations and epigenetic modifications in ATL cells activate TCR signaling. Therefore, we believe that expression of UCK2 in HTLV-1-infected cells is induced by dysregulated TCR signaling. Recently, we established azacitidine-resistant (AZA-R) cells showing absent expression of UCK2. AZA-R cells proliferated normally in vitro, whereas UCK2 knockdown inhibited ATL cell growth. Although uridine and cytidine accumulated in AZA-R cells, possibly because of dysfunction of pyrimidine salvage biosynthesis induced by loss of UCK2 expression, the amount of UTP and CTP was almost the same as in parental cells. Furthermore, AZA-R cells were more susceptible to an inhibitor of dihydroorotic acid dehydrogenase, which performs the rate-limiting enzyme of de novo pyrimidine nucleotide biosynthesis, and more resistant to dipyridamole, an inhibitor of pyrimidine salvage biosynthesis, suggesting that AZA-R cells adapt to UCK2 loss by increasing de novo pyrimidine nucleotide biosynthesis. Taken together, the data suggest that fine-tuning pyrimidine biosynthesis supports vigorous cell proliferation of both normal T cells and ATL cells.

Novel Midkine Inhibitor Induces Cell Cycle Arrest and Apoptosis in Multiple Myeloma

BACKGROUND/AIM

Multiple myeloma (MM), the second most common hematological malignancy, is characterized by the accumulation of malignant plasma cells within the bone marrow. Despite various drug classes for MM treatment, it remains incurable, necessitating novel and efficacious agents. This study aims to explore the anti-cancer activity of a midkine inhibitor, iMDK (C21H13FN2O2S), in myeloma cell lines.

MATERIALS AND METHODS

This study assessed the antiproliferative activity using the MTT assay. Cell cycle and apoptosis were evaluated using flow cytometry. To further investigate the inhibitory mechanism, western blotting was used to detect cell cycle-related proteins, pro-apoptotic proteins, and anti-apoptotic proteins.

RESULTS

iMDK inhibits MM cell proliferation in a dose- and time-dependent manner, inducing cell cycle arrest and apoptosis. The reduction in Cdc20 expression by iMDK treatment leads to G2/M phase cell cycle arrest. Furthermore, iMDK down-regulates anti-apoptotic proteins (Bcl-2, Bcl-xL, Mcl-1, and c-FLIP), thereby activating both intrinsic and extrinsic apoptosis pathways.

CONCLUSION

iMDK could be a potential candidate for MM treatment.

Reversal of Hyperglycemia by Subcutaneous Islet Engraftment Using an Atelocollagen Sponge as a Scaffold

Type 1 diabetes mellitus (T1DM) affects 8.4 million people worldwide, with patients primarily relying on exogenous insulin injections to maintain blood glucose levels. Islet transplantation via the portal vein has allowed for the direct internal release of insulin by glucose-sensitive islets. However, this method might not be desirable for future cell therapy transplanting pluripotent stem cell-derived β cells, facing challenges including difficulties in cell retrieval and graft loss due to the instant blood-mediated inflammatory reaction (IBMIR). Here, we established a subcutaneous transplantation protocol using an atelocollagen sponge as a scaffold. While the subcutaneous site has many advantages, the lack of a vascular bed limits its application. To address this issue, we performed angiogenesis stimulation at the transplantation site using bFGF absorbed in a gelatin sponge (Spongel), significantly improving the microvascular area. Our in vivo experiments also revealed angiogenesis stimulation is crucial for reversing hyperglycemia in streptozotocin (STZ)-induced diabetic mice. In addition to the angiogenic treatment, an atelocollagen sponge is used to carry the islets and helps avoid graft leakage. With 800 mouse islets delivered by the atelocollagen sponge, the STZ-induced diabetic mice showed a reversal of hyperglycemia and normalized glucose intolerance. Their normoglycemia was maintained until the graft was removed. Analysis of the harvested islet grafts exhibited a high vascularization and preserved morphologies, suggesting that using an atelocollagen sponge as a scaffold helps maintain the viability of the islet grafts.

The IL-17-IL-17RA axis is required to promote osteosarcoma progression in mice

Osteosarcoma is rare but is the most common bone tumor. Diagnostic tools such as magnetic resonance imaging development of chemotherapeutic agents have increased the survival rate in osteosarcoma patients, although 5-year survival has plateaued at 70%. Thus, development of new treatment approaches is needed. Here, we report that IL-17, a proinflammatory cytokine, increases osteosarcoma mortality in a mouse model with AX osteosarcoma cells. AX cell transplantation into wild-type mice resulted in 100% mortality due to ectopic ossification and multi-organ metastasis. However, AX cell transplantation into IL-17-deficient mice significantly prolonged survival relative to controls. CD4-positive cells adjacent to osteosarcoma cells express IL-17, while osteosarcoma cells express the IL-17 receptor IL-17RA. Although AX cells can undergo osteoblast differentiation, as can patient osteosarcoma cells, IL-17 significantly inhibited that differentiation, indicating that IL-17 maintains AX cells in the undifferentiated state seen in malignant tumors. By contrast, IL-17RA-deficient mice transplanted with AX cells showed survival comparable to wild-type mice transplanted with AX cells. Biopsy specimens collected from osteosarcoma patients showed higher expression of IL-17RA compared to IL-17. These findings suggest that IL-17 is essential to maintain osteosarcoma cells in an undifferentiated state and could be a therapeutic target for suppressing tumorigenesis.

Folate-Appended Hydroxypropyl-β-Cyclodextrin Induces Autophagic Cell Death in Acute Myeloid Leukemia Cells

Acute myeloid leukemia (AML) is a heterogenous myeloid neoplasm that remains challenging to treat. Because intensive conventional chemotherapy reduces survival rates in elderly patients, drugs with lower toxicity and fewer side effects are needed urgently. 2-Hydroxypropyl-β-cyclodextrin (HP-β-CyD) is used clinically as a pharmaceutical excipient for poorly water-soluble drugs. Previously, we showed that HP-β-CyD exerts antitumor activity by disrupting cholesterol homeostasis. Recently, we developed folate-conjugated HP-β-CyD (FA-HP-β-CyD) and demonstrated its potential as a new antitumor agent that induces not only apoptosis, but also autophagic cell death; however, we do not know whether FA-HP-β-CyD exerts these effects against AML. Here, we investigated the effects of FA-HP-β-CyD on folate receptor (FR)-expressing AML cells. We found that the cytotoxic activity of FA-HP-β-CyD against AML cells was stronger than that of HP-β-CyD. Also, FA-HP-CyD induced the formation of autophagosomes in AML cell lines. FA-HP-β-CyD increased the inhibitory effects of cytarabine and a BCL-2-selective inhibitor, Venetoclax, which are commonly used treat elderly AML patients. Notably, FA-HP-β-CyD suppressed the proliferation of AML cells in BALB/c nude recombinase-activating gene-2 (Rag-2)/Janus kinase 3 (Jak3) double-deficient mice with AML. These results suggest that FA-HP-β-CyD acts as a potent anticancer agent for AML chemotherapy by regulating autophagy.

γ-aminobutyric acid B2 receptor: A potential therapeutic target for cholangiocarcinoma in patients with diabetes mellitus

BACKGROUND

The association between diabetes mellitus (DM) and the increased risk and progression of cholangiocarcinoma (CCA) has been reported with unclear underlying mechanisms. Previous studies showed that γ-aminobutyric acid (GABA) B2 receptor (GABBR2) was upregulated in CCA cells cultured in high glucose (HG) conditions. Roles of GABA receptors in CCA progression have also been studied, but their association with DM and hyperglycemia in CCA remains unclarified.

AIM

To investigate the effects of hyperglycemia on GABBR2 expression and the potential use of GABBR2 as a CCA therapeutic target.

METHODS

CCA cells, KKU-055 and KKU-213A, were cultured in Dulbecco Modified Eagle's Medium supplemented with 5.6 mmol/L (normal glucose, NG) or 25 mmol/L (HG) glucose and assigned as NG and HG cells, respectively. GABBR2 expression in NG and HG cells was investigated using real-time quantitative polymerase chain reaction and western blot. Expression and localization of GABBR2 in CCA cells were determined using immunocytofluorescence. GABBR2 expression in tumor tissues from CCA patients with and without DM was studied using immunohistochemistry, and the correlations of GABBR2 with the clinicopathological characteristics of patients were analyzed using univariate analysis. Effects of baclofen, a GABA-B receptor agonist, on CCA cell proliferation and clonogenicity were tested using the MTT and clonogenic assays. Phospho-kinases arrays were used to screen the affected signaling pathways after baclofen treatment, and the candidate signaling molecules were validated using the public transcriptomic data and western blot.

RESULTS

GABBR2 expression in CCA cells was induced by HG in a dose- and time-dependent manner. CCA tissues from patients with DM and hyperglycemia also showed a significantly higher GABBR2 expression compared with tumor tissues from those with euglycemia (P < 0.01). High GABBR2 expression was significantly associated with a poorer non-papillary histological subtype but with smaller sizes of CCA tumors (P < 0.05). HG cells of both tested CCA cell lines were more sensitive to baclofen treatment. Baclofen significantly suppressed the proliferation and clonogenicity of CCA cells in both NG and HG conditions (P < 0.05). Phospho-kinase arrays suggested glycogen synthase kinase 3 (GSK3), β-catenin, and the signal transducer and activator of transcription 3 (STAT3) as candidate signaling molecules under the regulation of GABBR2, which were verified in NG and HG cells of the individual CCA cell lines. Cyclin D1 and c-Myc, the common downstream targets of GSK3/β-catenin and STAT3 involving cell proliferation, were accordingly downregulated after baclofen treatment.

CONCLUSION

GABBR2 is upregulated by HG and holds a promising role as a therapeutic target for CCA regardless of the glucose condition.

Diminishing acetyl-CoA carboxylase 1 attenuates CCA migration via AMPK-NF-κB-snail axis

Cholangiocarcinoma (CCA), a cancer of the biliary tract, is a significant health problem in Thailand. Reprogramming of cellular metabolism and upregulation of lipogenic enzymes have been revealed in CCA, but the mechanism is unclear. The current study highlighted the importance of acetyl-CoA carboxylase 1 (ACC1), a rate-limiting enzyme in de novo lipogenesis, on CCA migration. ACC1 expression in human CCA tissues was determined by immunohistochemistry. The results demonstrated that increased ACC1 was related to the shorter survival of CCA patients. Herein, ACC1-deficient cell lines (ACC1-KD) were generated by the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (cas9) system and were used for the comparative study. The ACC1 levels in ACC1-KD were 80-90 % lower than in parental cells. Suppression of ACC1 significantly reduced intracellular malonyl-CoA and neutral lipid contents. Two-fold growth retardation and 60-80 % reduced CCA cell migration and invasion were observed in ACC1-KD cells. The reduced 20-40 % of intracellular ATP levels, AMPK activation, lowered NF-κB p65 nuclear translocation, and snail expression were emphasized. Migration of ACC1-KD cells was restored by supplementation with palmitic acid and malonyl-CoA. Altogether, the importance of rate-limiting enzyme in de novo fatty acid synthesis, ACC1, and AMPK-NF-κB-snail axis on CCA progression was suggested herein. These might be the novel targets for CCA drug design. (ACC1, AMPK, Cholangiocarcinoma, De novo lipogenesis, NF-κB, Palmitic acid).

Establishment and characterization of a novel cancer stem-like cell of cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive malignant tumor of bile duct epithelia. Recent evidence suggests the impact of cancer stem cells (CSC) on the therapeutic resistance of CCA; however, the knowledge of CSC in CCA is limited due to the lack of a CSC model. In this study, we successfully established a stable sphere-forming CCA stem-like cell, KKU-055-CSC, from the original CCA cell line, KKU-055. The KKU-055-CSC exhibits CSC characteristics, including 1) the ability to grow stably and withstand continuous passage for a long period of culture in the stem cell medium, 2) high expression of stem cell markers, 3) low responsiveness to standard chemo-drugs, 4) multi-lineage differentiation, and 5) faster and constant expansive tumor formation in xenograft mouse models. To identify the CCA-CSC-associated pathway, we have performed a global proteomics and functional cluster/network analysis. Proteomics identified the 5925 proteins in total, and the significantly upregulated proteins in CSC compared with FCS-induced differentiated CSC and its parental cells were extracted. Network analysis revealed that high mobility group A1 (HMGA1) and Aurora-A signaling via the STAT-3 pathways were enriched in KKU-055-CSC. Knockdown of HMGA1 in KKU-055-CSC suppressed the expression of stem cell markers, induced the differentiation followed by cell proliferation, and enhanced sensitivity to chemo drugs including Aurora A inhibitors. In silico analysis demonstrated that the expression of HMGA1 was correlated with Aurora-A expressions and poor survival of CCA patients. In conclusion, we have established a unique CCA stem-like cell model and identified the HMGA1-Aurora-A signaling as an important pathway for CSC-CCA.

Shikonin Induces ROS-Dependent Apoptosis Via Mitochondria Depolarization and ER Stress in Adult T Cell Leukemia/Lymphoma

Adult T cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy that develops in some elderly human T-cell leukemia virus (HTVL-1) carriers. ATLL has a poor prognosis despite conventional and targeted therapies, and a new safe and efficient therapy is required. Here, we examined the anti-ATLL effect of Shikonin (SHK), a naphthoquinone derivative that has shown several anti-cancer activities. SHK induced apoptosis of ATLL cells accompanied by generation of reactive oxygen species (ROS), loss of mitochondrial membrane potential, and induction of endoplasmic reticulum (ER) stress. Treatment with a ROS scavenger, N-acetylcysteine (NAC), blocked both loss of mitochondrial membrane potential and ER stress, and prevented apoptosis of ATLL cells, indicating that ROS is an upstream trigger of SHK-induced apoptosis of ATLL cells through disruption of the mitochondrial membrane potential and ER stress. In an ATLL xenografted mouse model, SHK treatment suppressed tumor growth without significant adverse effects. These results suggest that SHK could be a potent anti-reagent against ATLL.

Dihydroartemisinin Induced Apoptosis and Synergized With Chemotherapy in Pleural Effusion Lymphoma Cells

BACKGROUND/AIM

Primary effusion lymphoma (PEL) is a rare aggressive B-cell lymphoma associated with HHV-8. With a median survival of fewer than six months, the prognosis of the disease with current standard therapies is usually dismal. Dihydroartemisinin (DHA) is a derivative of artemisinin, originally designed as an antimalarial drug. Several studies have shown that this compound also demonstrates anti-cancer activity in various types of cancer, including hematologic malignancies.

MATERIALS AND METHODS

Anti-proliferation activity of DHA on 5 PEL cell lines was assessed by MTT assay. Cell cycle arrest was determined by propidium iodide staining and flow cytometry analysis. DHA-induced PEL apoptosis was shown by annexin V/PI staining and western blotting for cleaved caspases 3, 8, and 9. An inhibitory effect on PEL growth was evaluated in a PEL-xenograft mouse model. A synergistic effect of DHA and doxorubicin combination treatment was shown in vitro.

RESULTS

DHA showed anti-proliferative activity on PEL and induced caspase-dependent apoptosis in a time- and dose-dependent manner. DHA-induced cell death appeared to be triggered by increased levels of reactive oxygen species (ROS). N-acetylcysteine treatment inhibited DHA-induced ROS elevation and suppressed expression of cleaved caspases leading to significantly reduced PEL apoptosis. DHA treatment also demonstrated an inhibitory effect on PEL cell growth in an in-vivo xenograft model. Moreover, we found that a combination treatment of DHA and doxorubicin, the standard chemotherapy drug for PEL, demonstrated a synergistic effect on PEL cell lines.

CONCLUSION

DHA is a potentially effective candidate drug for PEL treatment.