Arsenic trioxide synergizes with B7H3-mediated immunotherapy to eradicate hepatocellular carcinomas

B7 homolog 3 in pancreatic cancer

Despite advances in cancer treatment, pancreatic cancer (PC) remains a disease with high mortality rates and poor survival outcomes. The B7 homolog 3 (B7-H3) checkpoint molecule is overexpressed among many malignant tumors, including PC, with low or absent expression in healthy tissues. By modulating various immunological and nonimmunological molecular mechanisms, B7-H3 may influence the progression of PC. However, the impact of B7-H3 on the survival of patients with PC remains a subject of debate. Still, most available scientific data recognize this molecule as a suppressive factor to antitumor immunity in PC. Furthermore, it has been demonstrated that B7-H3 stimulates the migration, invasion, and metastasis of PC cells, and enhances resistance to chemotherapy. In preclinical models of PC, B7-H3-targeting monoclonal antibodies have exerted profound antitumor effects by increasing natural killer cell-mediated antibody-dependent cellular cytotoxicity and delivering radioisotopes and cytotoxic drugs to the tumor site. Finally, PC treatment with B7-H3-targeting antibody-drug conjugates and chimeric antigen receptor T cells is being tested in clinical studies. This review provides a comprehensive analysis of all PC-related studies in the context of B7-H3 and points to deficiencies in the current data that should be overcome by future research.

Can arsenic do anything good? Arsenic nanodrugs in the fight against cancer - last decade review

Arsenic has been an element of great interest among scientists for many years as it is a widespread metalloid in our ecosystem. Arsenic is mostly recognized with negative connotations due to its toxicity. Surely, most of us know that a long time ago, arsenic trioxide was used in medicine to treat, mainly, skin diseases. However, not everyone knows about its very wide and promising use in the treatment of cancer. Initially, in the seventies, it was used to treat leukemia, but new technological possibilities and the development of nanotechnology have made it possible to use arsenic trioxide for the treatment of solid tumours. The most toxic arsenic compound - arsenic trioxide - as the basis of anticancer drugs in which they function as a component of nanoparticles is used in the fight against various types of cancer. This review aims to present the current solutions in various cancer treatment using arsenic compounds with different binding motifs and methods of preparation to create targeted nanoparticles, nanodiamonds, nanohybrids, nanodrugs, or nanovehicles.

B7-H3 chimeric antigen receptor-modified T cell shows potential for targeted treatment of acute myeloid leukaemia

BACKGROUND AND AIMS

Chimeric antigen receptor (CAR)-T cell therapy is a novel type of immunotherapy. However, the use of CAR-T cells to treat acute myeloid leukaemia (AML) has limitations. B7-H3 is expressed in several malignancies, including some types of AML cells. However, its expression in normal tissues is low. Therefore, B7-H3 is ideal for targeted AML therapy.

MATERIALS AND METHODS

First, we constructed B7-H3 CAR that can target B7-H3, and then constructed B7-H3-CAR-T cells in vitro, which were co-incubated with six AML cell lines expressing different levels of B7-H3, respectively. The toxicity and cytokines were detected by flow cytometry. In vivo, AML model was established in B-NSG mice to study the toxicity of B7-H3-CAR T on AML cells.

RESULTS

In vitro functional tests showed that B7-H3-CAR-T cells were cytotoxic to B7-H3-positive AML tumor cells and had good scavenging effect on B7-H3-expressing AML cell lines, and the cytokine results were consistent. In vivo, B7-H3-CAR-T cells significantly inhibited tumor cell growth in a mouse model of AML, prolonging mouse survival compared with controls.

CONCLUSION

B7-H3-CAR-T cells may serve as a novel therapeutic method for the targeted treatment of AML.

Nanocarrier-based delivery of arsenic trioxide for hepatocellular carcinoma therapy

Hepatocellular carcinoma (HCC) poses a severe threat to human health and economic development. Despite many attempts at HCC treatment, most are inevitably affected by the genetic instability and variability of tumor cells. Arsenic trioxide (ATO) has shown to be effective in HCC. However, time-consuming challenges, especially the optimal concentration in tumor tissue and bioavailability of ATO, remain to be overcome for its transition from the bench to the bedside. To bypass these issues, nanotechnology-based delivery systems have been developed for prevention, diagnosis, monitoring and treatment in recent years. This article is a systematic overview of the latest contributions and detailed insights into ATO-loaded nanocarriers, with particular attention paid to strategies for improving the efficacy of nanocarriers of ATO.

ALYREF associated with immune infiltration is a prognostic biomarker in hepatocellular carcinoma

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ALYREF is a potential prognostic marker for hepatocellular carcinoma.

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ALYREF affects the biological function of hepatocellular carcinoma cells.

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ALYREF is associated with immune infiltration in hepatocellular carcinoma.

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The model constructed based on ALYREF-related immune genes provides a reference for the evaluation of immunotherapy.

Background

Although ALYREF has been demonstrated to have a role in a number of malignancies, its role in hepatocellular carcinoma (HCC) has received little attention. Our objective was to research at the prognostic value, biological role and relevance of ALYREF to the immune system in HCC.

Methods

The expression of ALYREF and its relationship with clinical parameters of HCC patients were analyzed by liver cancer cohort (LIHC) of The Cancer Genome Atlas. The expression and prognosis were verified by immunohistochemistry experiments. Gene transfection, CCK-8, scratch healing, transwell invasion and flow cytometry were used to assess the molecular function of ALYREF in vitro. The TIMER and TISIDB online data portals were used to assess the relevance of ALYREF to immunization. Stepwise regression analysis of ALYREF-related immune genes in the LIHC training set was used to construct a prognostic risk prediction model. Also, construct a nomogram to predict patient survival. The testing set for internal verification.

Results

Knockdown of ALYREF changed the biological phenotypes of HCC cells, such as proliferation, apoptosis, and invasion. In addition, the expression of ALYREF in HCC affected the level of immune cell infiltration and correlated with the overall survival time of patients. The constructed immune prognostic model allows for a valid assessment of patients.

Conclusion

ALYREF is increased in HCC, has an impact on cellular function and the immune system, and might be used as a prognostic marker.

Serum soluble B7-H3 is a prognostic marker for patients with non-muscle-invasive bladder cancer

Background

B7-H3 is a member of the B7 family of immune-regulatory ligands and is a costimulatory molecule promoting the T cell response in vitro. We herein investigated the clinical utility of serum soluble B7-H3 (sB7-H3) in patients with non-muscle invasive bladder cancer (NMIBC).

Methods

We analyzed 555 patients in whom NMIBC was diagnosed at Tokyo Metropolitan Tama Medical Center between 2008 and 2013. We measured the serum sB7-H3 (sB7-H3) level using the enzyme-linked immunosorbent assay (ELISA) and evaluated the utility of sB7-H3 as a prognostic biomarker for NMIBC. We used the Cox proportional hazards regression model to assess recurrence-free survival (RFS) and progression-free survival (PFS) with the sB7-H3 level.

Results

We detected high levels of sB7-H3 in the sera of 47% of patients with NMIBC versus only 8% in healthy donors. The increase of sB7-H3 was significantly associated with poor RFS and PFS. Multivariate analysis showed that elevated sB7-H3 was an independent prognostic factor of RFS and PFS. According to the European Organization for Research and Treatment of Cancer (EORTC), in intermediate-low and intermediate-high risk groups, the presence of sB7-H3 significantly determined the rate of recurrence and progression.

Conclusions

Our data suggested that evaluating serum sB7-H3 expression is a useful tool for predicting the prognosis of patients with NMIBC.

Old dog, new trick: Trivalent arsenic as an immunomodulatory drug

Trivalent arsenic (As(III)) is recently found to be an immunomodulatory agent. As(III) has therapeutic potential in several autoimmune and inflammatory diseases in vivo. In vitro, it selectively induces apoptosis of immune cells due to different sensitivity. At a non-toxic level, As(III) shows its multifaceted nature by inducing either pro- or anti-inflammatory functions of immune subsets. These effects are exerted by either As(III)-protein interactions or as a consequence of As(III)-induced homeostasis imbalance. The immunomodulatory properties also show synergistic effects of As(III) with cancer immunotherapy. In this review, we summarize the immunomodulatory effects of As(III), focusing on the effects of As(III) on immune subsets in vitro, on mouse models of immune-related diseases, and the role of As(III) in cancer immunotherapy. Updates of the mechanisms of action, the pioneer clinical trials, dosing, and adverse events of therapeutic As(III) are also provided.

Cancer vaccines and immunotherapeutic approaches in hepatobiliary and pancreatic cancers

Hepatobiliary and pancreatic cancers along with other gastrointestinal malignancies remain the leading cause of cancer-related deaths worldwide. Strategies developed in the recent years on immunotherapy and cancer vaccines in the setting of primary liver cancer as well as in pancreatic cancer are the scope of this review. Significance of orthotopic and autochthonous animal models which mimic and/or closely reflect human malignancies allowing for a prompt and trustworthy analysis of new therapeutics is underlined. Combinational approaches that on one hand, specifically target a defined cancer-driving pathway, and on the other hand, restore the functions of immune cells, which effector functions are often suppressed by a tumor milieu, are shown to have the strongest perspectives and future directions. Among combinational immunotherapeutic approaches a personalized- and individual cancer case-based therapy is of special importance.

Emerging targets in cancer immunotherapy

The first generation of immune checkpoint inhibitors (anti-CTLA-4 and anti-PD-1/PD-L1) targeted natural immune homeostasis pathways, co-opted by cancers, to drive anti-tumor immune responses. These agents led to unprecedented results in patients with previously incurable metastatic disease and may become first-line therapies for some advanced cancers. However, these agents are efficacious in only a minority of patients. Newer strategies are becoming available that target additional immunomodulatory mechanisms to activate patients' own anti-tumor immune responses. Herein, we present a succinct summary of emerging immune targets with reported pre-clinical efficacy that have progressed to active investigation in clinical trials. These emerging targets include co-inhibitory and co-stimulatory markers of the innate and adaptive immune system. In this review, we discuss: 1) T lymphocyte markers: Lymphocyte Activation Gene 3 [LAG-3], T-cell Immunoglobulin- and Mucin-domain-containing molecule 3 [TIM-3], V-domain containing Ig Suppressor of T cell Activation [VISTA], T cell ImmunoGlobulin and ITIM domain [TIGIT], B7-H3, Inducible T-cell Co-stimulator [ICOS/ICOS-L], CD27/CD70, and Glucocorticoid-Induced TNF Receptor [GITR]; 2) macrophage markers: CD47/Signal-Regulatory Protein alpha [SIRPα] and Indoleamine-2,3-Dioxygenase [IDO]; and 3) natural killer cell markers: CD94/NKG2A and the Killer Immunoglobulin-like receptor [KIR] family. Finally, we briefly highlight combination strategies and potential biomarkers of response and resistance to these cancer immunotherapies.

The third group of the B7-CD28 immune checkpoint family: HHLA2, TMIGD2, B7x, and B7-H3

The B7-CD28 family of ligands and receptors play important roles in T-cell co-stimulation and co-inhibition. Phylogenetically they can be divided into three groups. The recent discovery of the new molecules (B7-H3 [CD276], B7x [B7-H4/B7S1], and HHLA2 [B7H7/B7-H5]/TMIGD2 [IGPR-1/CD28H]) of the group III has expanded therapeutic possibilities for the treatment of human diseases. In this review, we describe the discovery, structure, and function of B7-H3, B7x, HHLA2, and TMIGD2 in immune regulation. We also discuss their roles in important pathological states such as cancers, autoimmune diseases, transplantation, and infection. Various immunotherapeutical approaches are emerging including antagonistic monoclonal antibodies and agonistic fusion proteins to inhibit or potentiate these molecules and pathways in cancers and autoimmune diseases.

Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells

Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells.

Chinese medicines for prevention and treatment of human hepatocellular carcinoma: current progress on pharmacological actions and mechanisms

Hepatocellular carcinoma (HCC) is one of leading causes of death in the world. Although various treatments have been developed, the therapeutic side effects are far from desirable. Chinese medicines (CMs, including plants, animal parts and minerals) have drawn a great deal of attention in recent years for their potential in the treatment of HCC. Most studies have shown that CMs may be able to retard HCC progression with multiple actions, either alone or in combination with other conventional therapies to improve quality of life in HCC patients. Additionally, CMs are used for preventing HCC occurrence. The aim of this study is to review the potential prophylactic and curative effects of CMs on human HCC and the possible mechanisms that underlie these pharmacological actions. Publications were collected and reviewed from PubMed and China National Knowledge Infrastructure from 2000 to 2014. Keywords for literature searches include "Chinese medicine", "Chinese herb", "traditional Chinese Medicine", "hepatocellular carcinoma" and "liver cancer". CMs in forms of pure compounds, isolated fractions, and composite formulas are included. Combination therapies are also considered. Both in vitro and in vivo efficacies of CMs are being discussed and the translational potential to bedside is to be discussed with clinical cases, which show the actions of CMs on HCC may include tumor growth inhibition, antimetastatic activities, anti-inflammation, anti-liver cancer stem cells, reversal on multi-drug resistance and induction/reduction of oxidative stress. Multiple types of molecules are found to contribute in the above actions. The review paper indicated that CMs might have potential to both prevent HCC occurrence and retard HCC progression with several molecular targets involved.

T cell coinhibition in prostate cancer: new immune evasion pathways and emerging therapeutics

T cell-mediated adaptive immune response is controlled by both positive costimulation and negative coinhibition, generated mainly by the interaction between the B7 family and their receptor CD28 family. Coinhibition is exploited by prostate cancer as an immune evasion pathway. Overexpression of coinhibitory B7x and B7-H3 in prostate cancer correlates with poor disease outcome, whereas tumor-infiltrating immune cells have enhanced expression of PD-L1 and its receptor PD-1. New insights into the complex mechanisms governing B7 expression in the tumor microenvironment have been reported and therapies aimed at overcoming T cell coinhibition with antagonistic monoclonal antibodies are emerging as effective tumor immunotherapies. Therapies that block B7x and B7-H3, either as monotherapies or in synergism with traditional therapies, should be pursued.

Effect of Sodium Arsenite on Mouse Skin Carcinogenesis

Arsenic is carcinogenic in human beings, and environmental exposure to arsenic is a public health issue that affects large populations worldwide. Thus, studies are needed to determine the mode of action of arsenic and prevent harmful effects arising from arsenic intake. The present study assessed the influence of sodium arsenite (As(3+)) on potentially carcinogenic processes that are either pre-existing or concomitant with chronic intake of water containing As(3+). Experiments using SenCar mice were designed to evaluate the effect of chronic administration of As(3+) (2, 20, or 200 mg of As(3+)/L) in drinking water that overlapped to varying degrees with a 2-stage carcinogenesis protocol carried out over 9 months. The results showed a time-dependent pattern. During early stages of carcinogenesis (6-12 weeks), animals exposed to As(3+) and the carcinogenesis protocol showed increased numbers of tumors compared to control animals. During late carcinogenesis (16-30 weeks), the number of tumors stabilized to below control values, but the tumors showed increased malignancy. These findings indicate that the outcomes of the 2-stage skin carcinogenesis protocol are modified by the presence of arsenite in drinking water, which increases the rate of carcinoma development.

Upregulation of the B7/CD28 family member B7-H3 in bladder cancer

Dysregulation of B7-H3 has been observed in a variety of types of human cancers. In the present study, the mRNA expression level of B7-H3 was analyzed in bladder cancer by performing semi-quantitative reverse transcription-polymerase chain reaction on clinical specimens from transitional cell carcinomas (TCCs) and their normal adjacent tissues (NATs). Immunohistochemical analysis was performed to compare the protein expression level of B7-H3 in TCCs and the paired NATs. The present study indicated that the B7-H3 mRNA expression level was significantly higher in the TCC samples compared with the paired NAT samples. Furthermore, immunohistochemical analyses indicated that the B7-H3 protein expression level was significantly upregulated in the TCC samples compared with in the paired NAT samples, indicating that B7-H3 dysregulation may be important in the progression of bladder cancer.

Arsenic trioxide potentiates the anti-cancer activities of sorafenib against hepatocellular carcinoma by inhibiting Akt activation

Sorafenib is the standard first-line systemic drug for advanced hepatocellular carcinoma (HCC), but it also induces the activation of Akt, which contributes to the mechanisms for the resistance to sorafenib. Arsenic trioxide (ATO) is a currently clinically used anticancer drug and displays its anticancer activities by inhibiting Akt activation. Therefore, we hypothesized that ATO may potentiate the anti-cancer activities of sorafenib against HCC. The results have demonstrated that ATO synergized with sorafenib to inhibit the proliferation and promote the apoptosis of HCC cells by diminishing the increased activation of Akt by sorafenib. ATO was shown to inhibit the expression or activation of Akt downstream factors, including glycogen synthase kinase (GSK)-3β, mammalian target of rapamycin (mTOR), ribosomal protein S6 kinase (S6K), and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1), which regulate cell apoptosis and were upregulated or activated by sorafenib. Both sorafenib and ATO downregulated the expression of cyclin D1, resulting in HCC cells arrested at G0/G1 phase. ATO downregulated the expression of Bcl-2 and Bcl-xL and upregulated the expression of Bax, indicating that ATO could induce the apoptosis of HCC cells through the intrinsic pathways; but sorafenib showed little effects on these proteins of Bcl-2 family. ATO synergized with sorafenib to suppress the growth of HCC tumors established in mice by inhibiting the proliferation and inducing the apoptosis of HCC cells in situ. These results indicate that ATO may be a potential agent that given in combination with sorafenib acts synergistically for treating HCC.

B7-H3 is expressed in human hepatocellular carcinoma and is associated with tumor aggressiveness and postoperative recurrence

B7-H3, a novel B7 family member, positively or negatively regulates T-cell responses. We investigated the clinical relevance and prognostic significance of B7-H3 in hepatocellular carcinoma (HCC). Western blotting showed B7-H3 upregulation in 17 of 24 (70.8 %) HCC tissues compared with nontumor liver tissues (p = 0.028). B7-H3 immunostaining on tissue microarrays containing 240 HCC patient samples indicated that 225 (93.8 %) tumors had aberrant B7-H3 expression, with strong intensity in 79 (32.9 %) cases, whereas B7-H3 expression in peritumor liver cells was weak in most cases (226; 94.2 %). Notably, patients with high/moderate tumor cell B7-H3 expression showed significantly poorer survival (p = 0.009) and increased recurrence (p = 0.002). After multivariable adjustment, high/moderate B7-H3 expression remained significant for an increased risk of recurrence (hazard ratio = 1.79; 95 % confidence interval = 1.19-2.70; p = 0.005). B7-H3 expression correlated with invasive phenotypes like vascular invasion and advanced tumor stage, and the metastatic potential of HCC cell lines. Flow cytometry showed that B7-H3 expression is inversely correlated with proliferation and interferon-γ production by infiltrating T cells. Interferon-γ stimulation significantly upregulated B7-H3 expression in HCC cells in vitro, implicating B7-H3 expression as a feedback mechanism to evade anti-tumor immunity. Importantly, the prognostic value of B7-H3 expression was validated in an independent cohort of 206 HCC patients. Collectively, our data suggest that B7-H3 was abundantly expressed in HCC and was associated with adverse clinicopathologic features and poor outcome. Thus, B7-H3 represents an attractive target for diagnostic and therapeutic manipulation in human HCC.

Cell-penetrating properties of the transactivator of transcription and polyarginine (R9) peptides, their conjugative effect on nanoparticles and the prospect of conjugation with arsenic trioxide

Cell-penetrating peptides (CPPs) are short chains of amino acids with the distinct ability to cross cell plasma membranes. They are usually between seven and 30 residues in length. The mechanism of action is still a highly debated subject among researchers; it seems that a commonality between all CPPs is the presence of positively charged residues within the amino acid chain. Polyarginine and the transactivator of transcription peptide are two widely used CPPs. One distinct application of these CPPs is the ability to further enhance the therapeutic properties of a range of different agents. One group of agents of particular importance are nanoparticles (NPs). Most NPs have no mechanism for cellular uptake. Hence, by conjugating CPPs to NPs, the amount of NPs taken up by cells can be increased, and therefore, the therapeutic benefits can be maximized. Some examples of this will be explored further in this review. In addition to CPPs, the concept of conjugation with the anticancer drug arsenic trioxide is reviewed and the prospect of transactivator of transcription-conjugated arsenic trioxide albumin microspheres is also discussed. Recent locked nucleic acid technology to stabilize nucleotides (RNA or DNA) aptamer complexes able to target cancer cells more specifically and selectively to kill tumour cells and spare normal body cells. NPs tagged with modified locked nucleic acid-aptamers have the potential to kill cancer cells more specifically and effectively while sparing normal cells.

ABT-737 Synergizes with Arsenic Trioxide to Induce Apoptosis of Gastric Carcinoma Cells In Vitro and In Vivo

OBJECTIVE: This study investigated the potential synergistic effects of two inducers of apoptosis: the small molecule ABT-737 and arsenic trioxide (ATO). METHODS: Human gastric carcinoma cell lines SGC-7901 and MGC-803 were used to determine the effects of ABT-737 and ATO (alone or in combination) on cell proliferation and apoptosis in vitro. In vivo effects of these drugs were investigated in SGC-7901 solid tumours, grown in immunodeficient mice. RESULTS: ABT-737 and ATO inhibited proliferation and induced apoptosis in SGC-7901 and MGC-803 cells in concentration- and time-dependent manners, and showed a synergistic effect. ABT-737 disturbed the binding of B cell lymphoma (Bcl)-2 homologous antagonist killer and Bcl-extra large; ATO downregulated myeloid cell leukaemia (Mcl)-1 protein and upregulated Mcl-1short, the short splicing variant. ABT-737 and ATO significantly suppressed SGC-7901 xenograft growth, synergistically inhibited tumour growth and induced apoptosis in vivo. CONCLUSIONS: This study provides preclinical evidence that ABT-737 and ATO synergize to induce apoptosis of gastric carcinoma cells, suggesting that further investigation of these agents (as potential treatments for gastric cancer) is warranted.

Novel alginate-enclosed chitosan-calcium phosphate-loaded iron-saturated bovine lactoferrin nanocarriers for oral delivery in colon cancer therapy

AIM

To develop polymeric-ceramic nanocarriers (NCs) in order to achieve oral delivery of the anticancer neutraceutical iron-saturated bovine lactoferrin (Fe-bLf) protein.

MATERIALS & METHODS

Fe-bLf or paclitaxel (Taxol®) were adsorbed onto calcium phosphate nanocores, enclosed in biodegradable polymers chitosan and alginate. The Fe-bLf or Taxol-loaded NCs indicated as AEC-CP-Fe-bLf or AEC-CP-Taxol NCs, respectively, were made by combination of ionic gelation and nanoprecipitation. Size distribution, morphology, internalization and release profiles of the NCs were studied along with evaluation of in vitro and in vivo anticancer activities and compared with paclitaxel.

RESULTS

AEC-CP-Fe-bLf NCs obtained spherical morphology and showed enhanced endocytosis, transcytosis and anticancer activity in Caco-2 cells in vitro. AEC-CP-Fe-bLf NCs were supplemented in an AIN 93G diet and fed to mice in both prevention and treatment human xenograft colon cancer models. AEC-CP-Fe-bLf NCs were found to be highly significantly effective when given orally, as a pretreatment, 1 week before Caco-2 cell injections. None of the mice from the AEC-CP-Fe-bLf NC-fed group developed tumors or showed any signs of toxicity, while the mice fed the control AIN 93G diet showed normal tumor growth. Fe-bLf or Taxol, when given orally in a diet as nanoformulations post-tumor development, showed a significant regression in the tumor size with complete inhibition of tumor growth later, while intratumoral injection of Taxol just delayed the growth of tumors. The pharmacokinetic and bioavailability studies indicated that nanoformulated Fe-bLf was predominantly present on tumor cells compared to non-nanoformulated Fe-bLf. Fe-bLf-loaded NCs were found to help in absorption of iron and thus may have utility in enhancing the iron uptake during iron deficiency without interfering with the absorption of calcium.

CONCLUSION

With the promising results of our study, the future potential of NC-loaded Fe-bLf in chemoprevention and in the treatment of human colon cancer, deserves further investigation for translational research and preclinical studies of other malignancies.

A study on the thermochemotherapy effect of nanosized As2O3/MZF thermosensitive magnetoliposomes on experimental hepatoma in vitro and in vivo

In this paper, we describe the synthesis and characterization of a nanosized, thermosensitive magnetoliposome encapsulating magnetic nanoparticles (MZFs) and antitumor drugs (As(2)O(3)). The nanoliposomes were spherical and mostly single volume, with an average diameter of 128.2 nm. Differential scanning calorimetry (DSC) showed a liposome phase transition temperature of 42.71 °C. After that, we studied the liposomes' anti-hepatoma effect in vitro and in vivo. The antitumor effect of the nanoliposomes on human hepatoma cells, SMMC-7721, and changes in expression of apoptosis-related proteins were examined in vitro. The results show that As(2)O(3)/MZF thermosensitive magnetoliposomes combined with hyperthermia had a great impact on the Bax/Bcl-2 ratio, which increased to 1.914 and exhibited a rapid response to induce apoptosis of tumor cells. An in situ rabbit liver tumor model was established and used to evaluate the antitumor effect of combined hyperthermia and chemotherapy following transcatheter arterial embolization with As(2)O(3)/MZF thermosensitive magnetoliposomes. The results demonstrated a strong anti-hepatoma effect, with a tumor volume inhibition rate of up to 85.22%. Thus, As(2)O(3)/MZF thermosensitive magnetoliposomes may play a great role in the treatment of hepatocarcinoma.

Re-inventing intratumoral immunotherapy for melanoma

Immunotherapeutics have been applied intratumorally to manage accessible lesions and to induce systemic immunity in malignant melanoma. Intratumoral bacillus Calmette-Guérin (BCG) has been used for 40 years, and intratumoral BCG, IL-2, IFN-α and imiquimod are recommended as treatment options for patients with in-transit melanoma metastases. Regression of cutaneous metastases can be achieved. Subcutaneous metastases are more refractory, and regression of uninjected, visceral metastases is infrequent. Other microbial products, cytokines, chemicals, immune cells, antibody and viral and plasmid vectors expressing immunologically active molecules have been tested. Antitumor activity has not been demonstrated to be superior to that of intratumoral BCG. There are few controlled trials, and whether survival is impacted with any approach has not yet been established. The immunotherapeutics applied and the intratumoral administration procedure itself can activate responses that are immune inhibitory. More rigorous clinical testing and improved understanding and modulation of regulatory immune responses are necessary.

A study on the preparation and characterization of plasmid DNA and drug-containing magnetic nanoliposomes for the treatment of tumors

Purpose:

To explore the preparation and characterization of a novel nanosized magnetic liposome containing the PEI-As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex.

Methods:

Mn_0.5Zn_0.5Fe₂O₄ and As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ nanoparticles were prepared by chemical coprecipitation and loaded with PEI. The PEI- As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex was characterized using transmission electron and scanning electron microscopy, X-ray diffraction, energy dispersive spectrometry, and Fourier transform infrared spectroscopy. Cell transfection experiments were performed to evaluate the transfect efficiency. Magnetic nanoliposomes were prepared by rotatory evaporation and their shape, diameter, and thermodynamic characteristics were observed.

Results:

Mn_0.5Zn_0.5Fe₂O₄ and PEI-As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ nanoparticles were spherical, with an average diameter of 20–40 nm. PEI-As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ was an appropriate carrier for the delivery of a foreign gene to HepG2 cells. Energy dispersive spectrometry results confirmed the presence of the elements nitrogen and arsenic. Nanoliposomes of approximately 100 nm were observed under a transmission electron microscope. Upon exposure to an alternating magnetic field, they also had good magnetic responsiveness, even though Mn_0.5Zn_0.5Fe₂O₄was modified by PEI and encased in liposomes. Temperatures increased to 37°C–54°C depending on different concentrations of PEI-As₂O₃/Mn_0.5Zn_0.5Fe₂O₄and remained stable thereafter.

Conclusion:

Our results suggest that PEI-As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ magnetic nanoliposomes are an excellent biomaterial, which has multiple benefits in tumor thermotherapy, gene therapy, and chemotherapy.

Genistein potentiates the effect of arsenic trioxide against human hepatocellular carcinoma: role of Akt and nuclear factor-κB

Hepatocellular carcinoma (HCC) is a highly lethal malignancy mostly because of de novo and acquired resistance to conventional chemotherapy. Constitutive activation of Akt and nuclear factor-κB (NF-κB) represent major cellular abnormalities associated with both the pathogenesis and therapeutic resistance of HCC. The aim of the present study was to determine whether genistein, a natural Akt/NF-κB inhibitor, could enhance the anti-HCC efficacy of ATO both in vitro and in vivo. Our results demonstrated that genistein not only potentiated the proliferation-inhibiting and apoptosis-inducing effect of ATO on human HCC cell lines in vitro, but also dramatically augmented its suppressive effect on both tumor growth and angiogenesis in nude mice. The mechanism is at least partially due to the suppressive effect of genistein both on the proper and ATO-induced Akt activation, and on the activity of NF-κB, and the latter correlated with the suppression of NF-κB regulated gene products, including cyclin D1, Bcl-xL, Bcl-2, c-myc, COX-2, and VEGF. These data suggest that the combination of ATO with genistein presents a promising therapeutic approach for the treatment of HCC.

The conformation change of Bcl-2 is involved in arsenic trioxide-induced apoptosis and inhibition of proliferation in SGC7901 human gastric cancer cells

Background

Arsenic trioxide has been established as a first-line agent for treating acute promyelocytic leukemia. Experimental data suggest that arsenic trioxide also can have a potential use as chemotherapeutic agent for other malignancies. The precise mechanisms of action of arsenic trioxide have though not been elucidated. As the role of Bcl-2 in arsenic trioxide-mediated cell apoptosis and conformation change of Bcl-2 in response to arsenic trioxide treatment has not been studied. The aim of the present study was to determine whether conformation change of Bcl-2 is involved in the action of arsenic trioxide.

Methods

Human gastric cancer SGC7901 cells were exposed to different concentrations of arsenic trioxide. Proliferation was measured by using the Kit-8 cell counting assay. Analysis of nuclear morphology was observed by DAPI staining. The apoptosis rates of cells treated with arsenic trioxide were analyzed by flow cytometry using Annexin V-FITC staining. The conformation change of Bcl-2 and Bax activation were detected by immunostaining and Western blot analysis. Total expression of Bcl-2 and Bax were examined by Western blot analysis.

Results

Arsenic trioxide inhibited the growth of human gastric cancer SGC7901 cells and induced apoptosis. There were two Bcl-2 phenotypes coexisting in SGC7901 cells and the Bcl-2 cytoprotective phenotype could change into a cytodestructive phenotype following conformational change of Bcl-2, triggered by arsenic trioxide exposure. Bax activation might also be involved in arsenic trioxide-induced Bcl-2 conformational change. Arsenic trioxide did not change levels of total Bcl-2 expression, but up-regulated total Bax expression for the treatment time ranging from 3 to 24 hours.

Conclusion

Arsenic trioxide induces apoptosis through induction of Bcl-2 conformational change, Bax activation and up-regulation of total Bax expression rather than affecting total Bcl-2 expression in human gastric cancer SGC7901 cells. The conformational change of Bcl-2 may be a novel described mechanism of arsenic trioxide-induced apoptosis in cancer cells.

Genistein synergizes with arsenic trioxide to suppress human hepatocellular carcinoma

Arsenic trioxide (ATO) is of limited therapeutic benefit for the treatment of solid tumors. Genistein exhibits anticancer and pro-oxidant activities, making it a potential candidate to enhance the efficacy of ATO whose cytotoxicity is oxidation-sensitive. This study sought to determine whether genistein synergizes with ATO to combat hepatocellular carcinoma (HCC). Three human HCC cell lines, namely HepG2, Hep3B, and SK-Hep-1, were incubated with ATO, genistein, or ATO + genistein. The cells were also pretreated with antioxidant agents N-acetyl-L-cysteine (NAC) or butylated hydroxyanisole (BHA). Cell viability, apoptosis, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (DeltaPsim), expression of Bcl-2, Bax, caspase-9, and -3, and release of cytochrome c into the cytosol were examined. The synergistic effect of ATO and genistein was also assessed using HepG2 xenografts subcutaneously established in BALB/c nude mice. The results show that genistein synergized with ATO to reduce viability, induce apoptosis, and diminish the DeltaPsim of cells. The combination therapy down-regulated Bcl-2 expression, up-regulated Bax expression, enhanced the activation of caspase-9 and -3, and increased the release of cytochrome c. The synergistic effect of ATO and genistein was diminished by pretreatment with NAC or BHA. Genistein increased the production of intracellular ROS, while ATO had little effect. Genistein synergized with a low dose of ATO (2.5 mg/kg) to significantly inhibit the growth of HepG2 tumors, and suppress cell proliferation and induce apoptosis in situ. There were no obvious side effects, as seen with a high dose of ATO (5 mg/kg). Combining genistein with ATO warrants investigation as a therapeutic strategy to combat HCC.

Clinical importance of B7-H3 expression in human pancreatic cancer

Background:

B7-H3 is a new member of the B7 ligand family and regulates T-cell responses in various conditions. However, the role of B7-H3 in tumour immunity is largely unknown. The purpose of this study was to evaluate the clinical significance of B7-H3 expression in human pancreatic cancer and the therapeutic potential for cancer immunotherapy.

Methods:

We investigated B7-H3 expression in 59 patients with pancreatic cancer by immunohistochemistry and real-time PCR. Furthermore, we examined the anti-tumour effect of B7-H3-blocking monoclonal antibody in vivo in a murine pancreatic cancer model.

Results:

Tumour-related B7-H3 expression was abundant in most human pancreatic cancer tissues and was significantly higher compared with that in non-cancer tissue or normal pancreas. Moreover, its expression was significantly more intense in cases with lymph node metastasis and advanced pathological stage. B7-H3 blockade promoted CD8⁺ T-cell infiltration into the tumour and induced a substantial anti-tumour effect on murine pancreatic cancer. In addition, the combination of gemcitabine with B7-H3 blockade showed a synergistic anti-tumour effect without overt toxicity.

Conclusion:

Our data show for the first time that B7-H3 may have a critical role in pancreatic cancer and provide the rationale for developing a novel cancer immunotherapy against this fatal disease.

Preparation of a nanosized as(2)o(3)/mn(0.5)zn(0.5)fe(2)o(4) complex and its anti-tumor effect on hepatocellular carcinoma cells

Manganese-zinc-ferrite nanoparticles (Mn_0.5Zn_0.5Fe₂O₄, MZF-NPs) prepared by an improved co-precipitation method and were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). Then thermodynamic testing of various doses of MZF-NPs was performed in vitro. The cytotoxicity of the Mn_0.5Zn_0.5Fe₂O₄ nanoparticles in vitro was tested by the MTT assay. A nanosized As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex was made by an impregnation process. The complex’s shape, component, envelop rate and release rate of As₂O₃ were measured by SEM, EDS and atom fluorescence spectrometry, respectively. The therapeutic effect of nanosized As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex combined with magnetic fluid hyperthermia (MFH) on human hepatocelluar cells were evaluated in vitro by an MTT assay and flow cytometry. The results indicated that Mn_0.5Zn_0.5Fe₂O₄ and nanosized As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex were both prepared successfully. The Mn_0.5Zn_0.5Fe₂O₄ nanoparticles had powerful absorption capabilities in a high-frequency alternating electromagnetic field, and had strong magnetic responsiveness. Moreover, Mn_0.5Zn_0.5Fe₂O₄ didn’t show cytotoxicity in vitro. The therapeutic result reveals that the nanosized As₂O₃/Mn_0.5Zn_0.5Fe₂O₄ complex can significantly inhibit the growth of hepatoma carcinoma cells.

Fine tuning the immune response through B7-H3 and B7-H4

SUMMARY

B7-H3 and B7-H4 belong to a new class of immune regulatory molecules, which primarily execute their functions in peripheral tissues to fine tune immune responses in target organs. In normal circumstances, while the mRNA for both molecules is broadly distributed, tight control at the post-transcriptional level is imposed. Under a pathogenic environment, such as inflammation and cancer, the control is often aberrant. Upon engaging their receptors, these molecules regulate the immune response in positive or negative ways depending on the expression and type of cells bearing the receptors. Thus, manipulation of the expression of these molecules and/or their receptors may represent a realistic opportunity to fine tune immune responses and to design new immunotherapeutic approaches.

Nanosized As2O3/Fe2O3 complexes combined with magnetic fluid hyperthermia selectively target liver cancer cells

AIM: To study the methods of preparing the magnetic nano-microspheres of Fe₂O₃ and As₂O₃/Fe₂O₃ complexes and their therapeutic effects with magnetic fluid hyperthermia (MFH).

METHODS: Nanospheres were prepared by chemical co-precipitation and their shape and diameter were observed. Hemolysis, micronucleus, cell viability, and LD₅₀ along with other in vivo tests were performed to evaluate the Fe₂O₃ microsphere biocompatibility. The inhibition ratio of tumors after Fe₂O₃ and As₂O₃/Fe₂O₃ injections combined with induced hyperthermia in xenograft human hepatocarcinoma was calculated.

RESULTS: Fe₂O₃ and As₂O₃/Fe₂O₃ particles were round with an average diameter of 20 nm and 100 nm as observed under transmission electron microscope. Upon exposure to an alternating magnetic field (AMF), the temperature of the suspension of magnetic particles increased to 41-51°C, depending on different particle concentrations, and remained stable thereafter. Nanosized Fe₂O₃ microspheres are a new kind of biomaterial without cytotoxic effects. The LD₅₀ of both Fe₂O₃ and As₂O₃/Fe₂O₃ in mice was higher than 5 g/kg. One to four weeks after Fe₂O₃ and As₂O₃/Fe₂O₃ complex injections into healthy pig livers, no significant differences were found in serum AST, ALT, BUN and Cr levels among the pigs of all groups (P > 0.05), and no obvious pathological alterations were observed. After exposure to alternating magnetic fields, the inhibition ratio of the tumors was significantly different from controls in the Fe₂O₃ and As₂O₃/Fe₂O₃ groups (68.74% and 82.79%, respectively; P < 0.01). Tumors of mice in treatment groups showed obvious necrosis, while normal tissues adjoining the tumor and internal organs did not.

CONCLUSION: Fe₂O₃ and As₂O₃/Fe₂O₃ complexes exerted radiofrequency-induced hyperthermia and drug toxicity on tumors without any liver or kidney damage. Therefore, nanospheres are ideal carriers for tumor-targeted therapy.

Antiangiogenic therapy enhances the efficacy of transcatheter arterial embolization for hepatocellular carcinomas

Transcatheter arterial embolization (TAE) is a well-established technique for unresectable hepatic malignancies. However, TAE can temporally halt the growth of hepatic tumors by blocking their arterial supply, but often tumors rapidly develop collateral blood vessels via angiogenesis. We have previously demonstrated that intraportal delivery of adeno-associated viral particles expressing angiostatin leads to long-term expression of angiostatin capable of inhibiting angiogenesis and suppressing the outgrowth of tumors in the liver. Thus, we hypothesize that adeno-associated virus (AAV)-mediated antiangiogenic therapy could enhance the efficacy of TAE to combat liver cancers. To achieve this objective, we engineered a recombinant AAV vector encoding rat angiostatin. Intraportal delivery of this vector led to long term and stable transgenic expression of angiostatin locally in rat hepatocytes and suppressed the growth of CBRH7919 hepatocellular carcinomas established in rat livers by inhibiting formation of neovessels. Although TAE therapy led to necrosis of liver tumors and suppressed their growth, the neovessels of tumors were rapidly reformed 3 weeks after TAE. However, intraportal injection of AAV-angiostatin inhibited the angiogenesis stimulated by TAE, synergized with TAE in suppressing growth of tumors established in livers and prolonged the survival of rats. In conclusion, these encouraging results warrant future investigation of the use of antiangiogenic therapy for enhancing the therapeutic efficacy of TAE to treat unresectable liver cancers.

Complete eradication of hepatocellular carcinomas by combined vasostatin gene therapy and B7H3-mediated immunotherapy

BACKGROUND/AIMS

B7H3 immunogene therapy is able to completely eradicate tumors when combined with an anti-vascular agent. The aim of this study was to determine whether vasostatin, a potent anti-angiogenic agent, could synergize with B7H3-mediated immunotherapy to combat hepatocellular carcinoma (HCC).

METHODS

Vasostatin and B7H3 expression plasmids were constructed, and the in vitro and in vivo expression and anti-angiogenic activity of recombinant vasostatin were measured. The anti-tumor activities of B7H3 and vasostatin alone and in combination were assessed using single and multiple H22 tumor models.

RESULTS

Gene transfer of vasostatin inhibited the proliferation of aortic endothelial cells, and angiogenesis in the chorioallantoic membrane assay. Subcutaneous H22 tumors established in BALB/c mice were completely eradicated in response to intratumoral injection of B7H3-expressing plasmids followed 24h later by vasostatin-expressing plasmids. In contrast, neither vasostatin nor B7H3 monotherapy was effective. Gene transfer of vasostatin inhibited tumor angiogenesis and enhanced infiltration of NK cells, whereas B7H3 therapy activated CD8+ and NK cells and increased their infiltration into tumors, and enhanced the levels of circulating IFN-gamma. B7H3 and vasostatin combination gene therapy was effective in combating a systemic challenge of parental H22 cells, and caused the complete regression of multiple distant tumor nodules.

CONCLUSIONS

Combining vasostatin anti-angiogenic therapy with B7H3-mediated immunotherapy warrants investigation as a therapeutic strategy to combat HCC, and other malignancies.

Opposing effects of arsenic trioxide on hepatocellular carcinomas in mice

Arsenic trioxide (As2O3) is a potent antitumor agent used to treat acute promyelocytic leukemia (APL) and, more recently, solid tumors. However, the dose of As2O3 required to suppress human xenographs in mice is markedly higher than that used to treat APL in humans. Paradoxically, low doses of As2O3 stimulate angiogenesis, which might be expected to promote tumor growth. Clearly, appropriate dosages of As2O3 are required to treat human patients to avoid toxicity and undesirable side effects. In the present study, we investigated As2O3 with respect to its toxicity and effects on tumor growth, angiogenesis and cell apoptosis using H22 hepatocellular carcinoma (HCC) cells in a mouse model of HCC. As2O3 inhibited tumor growth and angiogenesis, and enhanced tumor cell apoptosis at doses greater than 1 mg/kg, but mice lost weight and failed to thrive at doses of 4 mg/kg and greater. In contrast, low doses (<1 mg/kg) of As2O3 promoted tumor growth, upregulated the expression of vascular endothelial growth factor and tumor angiogenesis, and had no effect on tumor cell apoptosis. In vitro studies demonstrated that As2O3 inhibited the proliferation of H22 tumor cells and bovine aortic endothelial cells, and induced their apoptosis in a dose- and time-dependent fashion, suggesting that the mechanism of As2O3-mediated inhibition of tumor growth is due to direct effects of the drug on both tumor cells and endothelia. In summary, different doses of As2O3 have opposing effects on tumor growth and angiogenesis. The results demonstrate that As2O3 has a narrow window of therapeutic opportunity with respect to dosage, and that low doses of the drug as used in metronomic therapy should be used with extreme caution.