Preconditioning thermal therapy: flipping the switch on IL-6 for anti-tumour immunity

Silencing PADI-2 induces antitumor effects by downregulating NF-κB, Nrf2/HO-1 and AKT1 in A549 lung cancer cells

OBJECTIVE

This study aimed to investigate the tumorigenic role and regulatory pathways of peptidyl arginine deiminase 2 (PAD-2) in A549 lung cancer cells following treatment with small interfering RNA (PADI-2 siRNA) or the pharmacological pan-PAD inhibitor BB-Cl amidine.

MATERIALS AND METHODS

A549 lung cancer cells were treated with PADI-2 siRNA to knock down PADI-2 expression or with BB-Cl amidine to inhibit PAD2 activity. The effects on cell proliferation, migration, invasion, and cell cycle phases were assessed. Additionally, the expression levels of nuclear factor erythroid 2 p45-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), AKT serine/threonine kinase 1 (AKT), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin 6 (IL6), and p53 were analyzed to elucidate the underlying mechanisms involved.

RESULTS

The manipulation of PAD-2 expression or activity significantly influenced tumor cell behavior. Knockdown of PADI-2 in A549 cells reduced cell proliferation by inhibiting the S and G2 phases and decreasing cell migration and invasion. Inhibition of PADI-2 expression also suppressed the protein levels of Nrf2 and HO-1 via suppression of the AKT/NF-κB pathway. Furthermore, this inhibition enhanced the senescence-associated secretory phenotype (SASP) through the regulation of IL6 and p53, resulted in significant upregulation of SASP factors mainly, p21, Lamin B1 and HMGB1.

CONCLUSION

Downregulation of PADI-2 attenuated the proliferation, migration, and invasion of A549 lung cancer cells by modulating the Nrf2/HO-1/AKT signaling pathway. It also increased senescence in A549 lung cancer cells via IL6 and p53 key regulators. These findings highlight the potential of PADI-2 as a therapeutic target in lung cancer treatment.

Immune-inflammatory modulation by natural products derived from edible and medicinal herbs used in Chinese classical prescriptions

BACKGROUND

Edible and medicinal herbs1 (EMHs) refer to a class of substances with dual attribution of food and medicine. These substances are traditionally used as food and also listed in many international pharmacopoeias, including the European Pharmacopoeia, the United States Pharmacopoeia, and the Chinese Pharmacopoeia. Some classical formulas that are widely used in traditional Chinese medicine include a series of EMHs, which have been shown to be effective with obvious characteristics and advantages. Notably, these EMHs and Chinese classical prescriptions2 (CCPs) have also attracted attention in international herbal medicine research because of their low toxicity and high efficiency as well as the rich body of experience for their long-term clinical use.

PURPOSE

Our purpose is to explore the potential therapeutic effect of EMHs with immune-inflammatory modulation for the study of modern cancer drugs.

STUDY DESIGN

In the present study, we present a detailed account of some EMHs used in CCPs that have shown considerable research potential in studies exploring modern drugs with immune-inflammatory modulation.

METHODS

Approximately 500 publications in the past 30 years were collected from PubMed, Web of Science and ScienceDirect using the keywords, such as natural products, edible and medicinal herbs, Chinese medicine, classical prescription, immune-inflammatory, tumor microenvironment and some related synonyms. The active ingredients instead of herbal extracts or botanical mixtures were focused on and the research conducted over the past decade were discussed emphatically and analyzed comprehensively.

RESULTS

More than ten natural products derived from EMHs used in CCPs are discussed and their immune-inflammatory modulation activities, including enhancing antitumor immunity, regulating inflammatory signaling pathways, lowering the proportion of immunosuppressive cells, inhibiting the secretion of proinflammatory cytokines, immunosuppressive factors, and inflammatory mediators, are summarized.

CONCLUSION

Our findings demonstrate the immune-inflammatory modulating role of those EMHs used in CCPs and provide new ideas for cancer treatment in clinical settings.

Immunomodulatory and Anticancer Effects of Fridericia chica Extract-Loaded Nanocapsules in Myeloid Leukemia

Nanocapsules provide selective delivery and increase the bioavailability of bioactive compounds. In this study, we examined the anticancer and immunomodulatory potential of Fridericia chica (crajiru) extract encapsulated in nanocapsules targeting myeloid leukemias. Nanocapsules containing crajiru (nanocapsules-CRJ) were prepared via interfacial polymer deposition and solvent displacement. Size and polydispersity were measured by dynamic light scattering. Biological assays were performed on leukemia cell lines HL60 and K562 and on non-cancerous Vero cells and human PBMC. The anticancer activity was evaluated using cytotoxicity and clonogenic assays, while the immunomodulatory activity was evaluated by measuring the levels of pro- and anti-inflammatory cytokines in PBMC supernatants treated with concentrations of nanocapsules-CRJ. Nanocapsules-CRJ exhibited significant cytotoxic activity against HL60 and K562 cells at concentrations ranging from 0.75 to 50 μg/mL, with the greatest reductions in cell viability observed at 50 μg/mL (p < 0.001 for HL60; p < 0.01 for K562), while not affecting non-cancerous Vero cells and human PBMCs. At concentrations of 25 μg/mL and 50 μg/mL, nanocapsules-CRJ reduced the formation of HL60 and K562 colonies by more than 90% (p < 0.0001). Additionally, at a concentration of 12 μg/mL, nanocapsules-CRJ induced the production of the cytokines IL-6 (p = 0.0002), IL-10 (p = 0.0005), IL-12 (p = 0.001), and TNF-α (p = 0.005), indicating their immunomodulatory potential. These findings suggest that nanocapsules-CRJ hold promise as a potential therapeutic agent with both cytotoxic and immunomodulatory properties.

The exercise IL-6 enigma in cancer

Interleukin (IL)-6 elicits both anticancer and procancer effects depending on the context, which we have termed the 'exercise IL-6 enigma'. IL-6 is released from skeletal muscles during exercise to regulate short-term energy availability. Exercise-induced IL-6 provokes biological effects that may protect against cancer by improving insulin sensitivity, stimulating the production of anti-inflammatory cytokines, mobilising immune cells, and reducing DNA damage in early malignant cells. By contrast, IL-6 continuously produced by leukocytes in inflammatory sites drives tumorigenesis by promoting chronic inflammation and activating tumour-promoting signalling pathways. How can a molecule have such opposing effects on cancer? Here, we review the roles of IL-6 in chronic inflammation, tumorigenesis, and exercise-associated cancer prevention and define the factors that underpin the exercise IL-6 enigma.

Pharmacological assessment of the antineoplastic and immunomodulatory properties of a new spiroindolone derivative (7',8'-Dimethoxy-1',3'-dimethyl-1,2,3',4'-tetrahydrospiro[indole-3,5'-pyrazolo[3,4-c]isoquinolin]-2-one) in chronic myeloid leukemia

The discovery and development of effective novel compounds is paramount in oncology for improving cancer therapy. In this study, we developed a new derivative of spiroindolone (7',8'-Dimethoxy-1',3'-dimethyl-1,2,3',4'-tetrahydrospiro[indole-3,5'- pyrazolo[3,4-c]isoquinolin]-2-one) and evaluated its anticancer- and immunomodulatory potential in a vitro model of chronic leukemia. We utilized the chronic leukemia cell line K562, as well as non-cancerous peripheral blood mononuclear cells (PBMC) and Vero cells (kidney epithelium of Cercopithecus aethiops). We assessed the cytotoxicity of the compound using the MTT assay, and performed cell cycle assays to determine its impact on different stages of the cell cycle. To evaluate its antineoplastic activity, we conducted a colony formation test to measure the effect of the compound on the clonal growth of cancer cells. Furthermore, we evaluated the immunomodulatory activity of the compound by measuring the levels of pro and anti-inflammatory cytokines. The study findings demonstrate that the spiroindolone-derived compound exerted noteworthy cytotoxic effects against K562 cells, with an IC50 value of 25.27 µg/mL. Additionally, it was observed that the compound inhibited the clonal proliferation of K562 cells while displaying minimal toxicity to normal cells. The compound exhibited its antiproliferative activity by inducing G2/M cell cycle arrest, preventing the entry of K562 cells into mitosis. Notably, the compound demonstrated an immunomodulatory effect by upregulating the production of cytokines IL-6 and IL-12/23p40. In conclusion, the spiroindolone-derived compound evaluated in this study has demonstrated significant potential as a therapeutic agent for the treatment of chronic myeloid leukemia. Further investigations are warranted to explore its clinical applications.

Interleukin-6 in Hepatocellular Carcinoma: A Dualistic Point of View

Hepatocellular Carcinoma (HCC) is a pressing health concern, demanding a deep understanding of various mediators' roles in its development for therapeutic progress. Notably, interleukin-6 (IL-6) has taken center stage in investigations due to its intricate and context-dependent functions. This review delves into the dual nature of IL-6 in HCC, exploring its seemingly contradictory roles as both a promoter and an inhibitor of disease progression. We dissect the pro-tumorigenic effects of IL-6, including its impact on tumor growth, angiogenesis, and metastasis. Concurrently, we examine its anti-tumorigenic attributes, such as its role in immune response activation, cellular senescence induction, and tumor surveillance. Through a comprehensive exploration of the intricate interactions between IL-6 and the tumor microenvironment, this review highlights the need for a nuanced comprehension of IL-6 signaling in HCC. It underscores the importance of tailored therapeutic strategies that consider the dynamic stages and diverse surroundings within the tumor microenvironment. Future research directions aimed at unraveling the multifaceted mechanisms of IL-6 in HCC hold promise for developing more effective treatment strategies and improving patient outcomes.

[Diabetes mellitus and the female reproductive system tumors]

The article discusses various pathophysiological conditions and processes that lead to the development of tumors in diabetes mellitus. These include obesity, hyperglycemia, hyperinsulinemia, inflammation, and oxidative stress. The data of epidemiological studies are given, in which it was found that diabetes mellitus (both type 1 and type 2) increases the risk of developing the female reproductive system tumors, such as ovarian cancer, endometrial cancer, while for cervical cancer, vaginal cancer and vulvar cancer, such a relationship has not been clearly identified.

Cytotoxic and immunomodulatory potential of a novel [2-(4-(2,5-dimethyl-1H-pyrrol-1-yl)-1H-pyrazol-3-yl)pyridine] in myeloid leukemia

Cancer ranks among the leading causes of mortality worldwide. However, the efficacy of commercially available anticancer drugs is compromised by the emerging challenge of drug resistance. This study aimed to investigate the anticancer and immunomodulatory potential of a recently developed a novel [2-(4-(2,5-dimethyl-1 H-pyrrol-1-yl)- 1 H-pyrazol-3-yl) pyridine]. The cytotoxic potential of the compound was assessed using the MTT assay on both cancerous HL60 (acute myeloid leukemia) and K562 (chronic myeloid leukemia) cell lines, as well as non-cancerous Vero cells and human peripheral blood mononuclear cells (PBMCs). A clonogenic assay was employed to evaluate the anticancer efficacy of the compound, while flow cytometry was utilized to investigate its effect on cell cycle arrest. Furthermore, the immunomodulatory potential of the compound was assessed by quantifying inflammatory and anti-inflammatory biomarkers in the supernatant of PBMCs previously treated with the compound. Our study revealed that the novel pyridine ensemble exhibits selective cytotoxicity against HL60 (IC₅₀ = 25.93 µg/mL) and K562 (IC₅₀ = 10.42 µg/mL) cell lines, while displaying no significant cytotoxic effect on non-cancerous cells. In addition, the compound induced a decrease of 18% and 19% in the overall activity of COX-1 and COX-2, respectively. Concurrently, it upregulated the expression of cytokines including IL4, IL6, IL10, and IL12/23p40, while downregulating INFγ expression. These findings suggest that the compound has the potential to serve as a promising candidate for the treatment of acute and chronic myeloid leukemias due to its effective antiproliferative and immunomodulatory activities, without causing cytotoxicity in non-cancerous cells.

Hyperthermic Extracorporeal Applied Tumor Therapy for Six Cycles for Recurrent Metastatic Peritoneal Serous Papillary Carcinoma

An elderly female with failed third-line peritoneal serous papillary carcinoma with metastasis (ovarian cancer) was treated by our proprietary method of whole-body hyperthermia-a recirculating extracorporeal circuit at 42°C for 120 minutes. She received six cycles, 28 days apart. Five index lesions were measured prior to and after each treatment. Results showed stable disease with reduced standard uptake volume. She then restarted six cycles of a previously failed chemotherapy, resulting in no evidence of disease for nine months; she survived for 27 months. Using our technology, the patient experienced an improvement in the quality of life and an increase in survival.

Combination of STING and TLR 7/8 Agonists as Vaccine Adjuvants for Cancer Immunotherapy

Immunostimulatory adjuvants that potently activate antigen-presenting cells and (in turn) prime cytotoxic T cells are a key component of anticancer vaccines. In this study, we investigated a multi-adjuvant approach combining a TLR 7/8 agonist (522) and a STING agonist (DMXAA) to promote enhanced antigen cross-presentation, stimulate specific antitumor T-cell responses, and provide improved anticancer efficacy. In vitro experiments using bone marrow-derived dendritic cells (BMDCs) confirmed enhanced activation with the 522-DMXAA combination based on both co-stimulatory molecule expression and pro-inflammatory cytokine secretion. The immunization of mice with vaccines comprising both 522 and DMXAA resulted in greater antitumor efficacy in B16F10 melanoma and MB49 bladder tumor models relative to mono-agonist vaccines. Flow cytometry-based analysis of immune cells from immunized mice revealed the significant activation of antigen-presenting cells, increased numbers of activated and Ag-specific CD8+ T cells in the spleen and lymph nodes, modest NK cell activation, and an overall reduction in CD206⁺ macrophages. These results were supported by an increase in the levels of IFN-γ and a reduction in IL-10 levels in the sera. Taken together, these findings demonstrate the potential of the TLR7/8 and STING agonist combination as vaccine adjuvants to activate both innate and adaptive immune responses.

Vanadyl sulfate-enhanced oncolytic virus immunotherapy mediates the antitumor immune response by upregulating the secretion of pro-inflammatory cytokines and chemokines

Oncolytic viruses (OVs) are promising anticancer treatments that specifically replicate in and kill cancer cells and have profound immunostimulatory effects. We previously reported the potential of vanadium-based compounds such as vanadyl sulfate (VS) as immunostimulatory enhancers of OV immunotherapy. These compounds, in conjunction with RNA-based OVs such as oncolytic vesicular stomatitis virus (VSVΔ51), improve viral spread and oncolysis, leading to long-term antitumor immunity and prolonged survival in resistant tumor models. This effect is associated with a virus-induced antiviral type I IFN response shifting towards a type II IFN response in the presence of vanadium. Here, we investigated the systemic impact of VS+VSVΔ51 combination therapy to understand the immunological mechanism of action leading to improved antitumor responses. VS+VSVΔ51 combination therapy significantly increased the levels of IFN-γ and IL-6, and improved tumor antigen-specific T-cell responses. Supported by immunological profiling and as a proof of concept for the design of more effective therapeutic regimens, we found that local delivery of IL-12 using VSVΔ51 in combination with VS further improved therapeutic outcomes in a syngeneic CT26WT colon cancer model.

Hyperthermia-mediated changes in the tumor immune microenvironment using iron oxide nanoparticles

Iron oxide nanoparticles (IONPs) have often been investigated for tumor hyperthermia. IONPs act as heating foci in the presence of an alternating magnetic field (AMF). It has been shown that hyperthermia can significantly alter the tumor immune microenvironment. Typically, mild hyperthermia invokes morphological changes within the tumor, which elicits a secretion of inflammatory cytokines and tumor neoantigens. Here, we focused on the direct effect of IONP-induced hyperthermia on the various tumor-resident immune cell subpopulations. We compared direct intratumoral injection to systemic administration of IONPs followed by application of an external AMF. We used the orthotopic 4T1 mouse model, which represents aggressive and metastatic breast cancer with a highly immunosuppressive microenvironment. A non-inflamed and 'cold' microenvironment inhibits peripheral effector lymphocytes from effectively trafficking into the tumor. Using intratumoral or systemic injection, IONP-induced hyperthermia achieved a significant reduction of all the immune cell subpopulations in the tumor. However, the systemic delivery approach achieved superior outcomes, resulting in substantial reductions in the populations of both innate and adaptive immune cells. Upon depletion of the existing dysfunctional tumor-resident immune cells, subsequent treatment with clinically approved immune checkpoint inhibitors encouraged the repopulation of the tumor with 'fresh' infiltrating innate and adaptive immune cells, resulting in a significant decrease of the tumor cell population.

The Interplay between Oxidative Stress, Inflammation and Angiogenesis in Bladder Cancer Development

In 2018, 550,000 people were diagnosed with bladder cancer (BC), of which nearly 200,000 people died. Moreover, men are 4 times more likely than women to be diagnosed with BC. The risk factors include exposure to environmental and occupational chemicals, especially tobacco smoke, benzidine and genetic factors. Despite numerous studies, the molecular basis of BC development remains unclear. A growing body of evidence suggests that inflammation, oxidant-antioxidant imbalance and angiogenesis disorders may play a significant role in the development and progression of bladder cancer. The patients with bladder cancer were characterised by an increased level of reactive oxygen species (ROS), the products of lipid peroxidation, proinflammatory cytokines and proangiogenic factors as compared to controls. Furthermore, it was shown that polymorphisms localised in genes associated with these pathways may modulate the risk of BC. Interestingly, ROS overproduction may induce the production of proinflammatory cytokines, which finally activated angiogenesis. Moreover, the available literature shows that both inflammation and oxidative stress may lead to activation of angiogenesis and tumour progression in BC patients.

Rapid tumor inhibition via magnetic hyperthermia regulated by caspase 3 with time-dependent clearance of iron oxide nanoparticles

Among conventional cancer therapies, radio-frequency magnetic hyperthermia (MHT) has widely been investigated for use with magnetic nanoparticles (MNPs). However, the majority of in vivo biodistribution studies have tested very low MNP dosages (equivalent to magnetic resonance imaging (MRI) applications) to check for clearance rate; which is far below the clinical dose of MHT. Due to this poor validation in preclinical scenarios, quite a few MNPs already in clinical use were later discontinued, on grounds of unexpected clinical outcomes in terms of inflammation, and prolonged clearance in vivo. By exploiting an economical method of synthesis, we have developed chitosan-coated Fe₃O₄ nanoparticles with high heating efficiency performance. Their anti-tumor response was evaluated in an ectopic tumor model of C6 glioblastoma by MHT. The intratumoral injection of MNPs on days 1 and 7 resulted in rapid tumor inhibition rate of 69.4% within 8 days, with complete inhibition within 32 days, and no recurrence recorded over a 5-month follow-up. Notably, the MNP-mediated MHT therapy achieved the highest degree of therapeutic efficacy required for complete tumor ablation by combining controlled temperature range (<44 °C), reduced MNP dosage; much lower than in most reported studies, and AMF parameters (time of exposure and frequency) within the clinical safety limit. Periodic body weight measurements confirmed negligible adverse side effects in rats. The anti-tumor activity was validated by severe apoptosis (TUNEL, cleaved Caspase-3), reduced proliferation (Ki 67) and disrupted vasculature (CD 31) in the Fe₃O₄-MHT-treated group. Real-time gene expression of pro-inflammatory cytokines (IL-6, TNF-α, IL-1α, IL-1β) confirmed the intratumoral activation of IL-6, suggesting the role of immunomodulation in triggering the adaptive immune response for faster tumor regression in the treated group. In addition, the biodistribution and clearance rate of MNPs monitored using ICP-OES confirmed their time-dependent biodegradation via excretion (urine, feces), phagocytosis (liver) and circulatory system (blood), with negligible deposition in other major organs (kidney, heart, lungs). Although we could not show complete clearance of our MNPs within the time frame tested, future studies should focus on combining MHT with immunotherapy, and target tumors at a much-reduced iron dose, consequently improving in vivo clearance rate, and hence overcoming the limitations of MHT in clinical therapy.

Interleukin-34 contributes to poor prognosis in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a subtype characterized by the absence of therapeutic targets. It shows rapid progression, higher relapse, and poor prognosis, so the establishment of an effective therapeutic target is required. We focused on interleukin-34 (IL-34) that is a novel cytokine relating to inflammation and tumorigenesis. It has been reported that IL-34 correlates with poor prognosis of various cancers. In this study, we evaluated the relationship of IL-34 and prognosis in TNBC using human clinical information and mice model. We found that IL-34 was highly expressed in TNBC, and the survival rate in TNBC was significantly lower in patients with high IL-34 expression. Furthermore, multivariate analysis revealed that IL-34 independently affects prognosis. In murine TNBC model, IL-34 deficiency in tumor cells decreased in vivo tumor growth and increased inflammatory cytokine production from macrophages. These results suggest that tumor-derived IL-34 creates a favorable environment for TNBC cells. Thus, we showed a novel pathological role of IL-34 in TNBC and the potential of IL-34 as a therapeutic target for it.

Anticancer and Immunomodulatory Activities of a Novel Water-Soluble Derivative of Ellipticine

Cancer still remains a major public health concern around the world and the search for new potential antitumor molecules is essential for fighting the disease. This study evaluated the anticancer and immunomodulatory potential of the newly synthetized ellipticine derivate: sodium bromo-5,11-dimethyl-6H-pyrido[4,3-b]carbazole-7-sulfonate (Br-Ell-SO₃Na). It was prepared by the chlorosulfonation of 9-bromoellipticine. The ellipticine-7-sulfonic acid itself is not soluble, but its saponification with sodium hydroxide afforded a water-soluble sodium salt. The cytotoxicity of Br-Ell-SO₃Na was tested against cancerous (K562 cell line) and non-cancerous cells (Vero cell line and human peripheral blood mononuclear cells (PBMC)) using a Methylthiazoletetrazolium (MTT) assay. Cell cycle arrest was assessed by flow cytometry and the immunomodulatory activity was analyzed through an enzyme-linked immunosorbent assay (ELISA)_. The results showed that the Br-Ell-SO₃Na molecule has specific anticancer activity (IC₅₀ = 35 µM) against the K562 cell line, once no cytotoxicity effect was verified against non-cancerous cells. Cell cycle analysis demonstrated that K562 cells treated with Br-Ell-SO₃Na were arrested in the phase S. Moreover, the production of IL-6 increased and the expression of IL-8 was inhibited in the human PBMC treated with Br-Ell-SO₃Na. The results demonstrated that Br-Ell-SO₃Na is a promising anticancer molecule attested by its noteworthy activity against the K562 tumor cell line and immunomodulatory activity in human PBMC cells.

The Role of Hyperthermia in the Multidisciplinary Treatment of Malignant Tumors

Hyperthermia is often used in combination with chemotherapy and radiotherapy for cancer treatment. Recently, immunotherapy has become a popular research area, breaking exciting new ground with concurrent immunotherapy and hyperthermia. Much evidence has demonstrated the effectiveness of multidisciplinary synergistic therapy, and the underlying mechanism has been gradually explored. In this review, we focus on the mechanism of various cancer treatments in the current literature and recent advances in hyperthermia. Additionally, we review clinical studies of hyperthermia combined with other therapies in the previous 10 years and propose future prospects for hyperthermia in multidisciplinary synergistic therapy.

Molecular and biological rationale of hyperthermia as radio- and chemosensitizer

Mild hyperthermia, local heating of the tumour up to temperatures <43 °C, has been clinically applied for almost four decades and has been proven to substantially enhance the effectiveness of both radiotherapy and chemotherapy in treatment of primary and recurrent tumours. Clinical results and mechanisms of action are discussed in this review, including the molecular and biological rationale of hyperthermia as radio- and chemosensitizer as established in in vitro and in vivo experiments. Proven mechanisms include inhibition of different DNA repair processes, (in)direct reduction of the hypoxic tumour cell fraction, enhanced drug uptake, increased perfusion and oxygen levels. All mechanisms show different dose effect relationships and different optimal scheduling with radiotherapy and chemotherapy. Therefore, obtaining the ideal multi-modality treatment still requires elucidation of more detailed data on dose, sequence, duration, and possible synergisms between modalities. A multidisciplinary approach with different modalities including hyperthermia might further increase anti-tumour effects and diminish normal tissue damage.

Racial Differences in Immunological Landscape Modifiers Contributing to Disparity in Prostate Cancer

Prostate cancer affects African Americans disproportionately by exhibiting greater incidence, rapid disease progression, and higher mortality when compared to their Caucasian counterparts. Additionally, standard treatment interventions do not achieve similar outcome in African Americans compared to Caucasian Americans, indicating differences in host factors contributing to racial disparity. African Americans have allelic variants and hyper-expression of genes that often lead to an immunosuppressive tumor microenvironment, possibly contributing to more aggressive tumors and poorer disease and therapeutic outcomes than Caucasians. In this review, we have discussed race-specific differences in external factors impacting internal milieu, which modify immunological topography as well as contribute to disparity in prostate cancer.

PNU-74654 enhances the antiproliferative effects of 5-FU in breast cancer and antagonizes thrombin-induced cell growth via the Wnt pathway

The Wnt/β-catenin pathway is one of the most common pathways dysregulated in breast cancer, and may, therefore, be a potential-therapeutic target. We have investigated the effects of PNU-74654 in breast cancer, as a Wnt/β-catenin inhibitor, either alone or in combination with fluorouracil (5-FU). PNU-74654 suppressed cell growth at an IC 50 of 122 ± 0.4 μmol/L and synergistically enhanced the antiproliferative activity of gemcitabine by modulating the Wnt pathway. Using a 3D cell culture model, we found that the PNU-74654 caused tumor shrinkage. It reduced the migration of MCF-7 cells (by an 18% reduction in invasive behavior) after the treatment with PNU-74654 through perturbation of E-cadherin and MMP3/9. PNU-74654/5-FU combination enhanced the percentages of cells in S-phase and significantly increased apoptosis. Moreover, our data showed that this agent was able to inhibit the growth of tumor in a xenograft model, although this effect was more pronounced in the animals treated with PNU-74654 plus 5-FU. These data show the ability of PNU-74654 to specifically target Wnt pathway, interfere with cell proliferation, induce-apoptosis, reduce-migration, and synergistically interact with 5-FU, supporting further studies on this novel therapeutic-approach for breast cancer.

IL-6 Activities in the Tumour Microenvironment. Part 1

The predominant role of IL-6 in cancer is its key promotion of tumour growth. IL-6 binds IL-6 receptor (IL-6R) and the membrane-bound glycoprotein gp130. The complex I-6/IL-6R/gp130 starts the Janus kinases (JAKs) and signal transducer and activator of transcription 3 (STAT3) or JAK/STAT3 pathway. IL-6 R exits in two forms: a membrane-bound IL-6Rα subunit (mIL-6R) that participates in classic signalling pathway and soluble IL-6R subunit (sIL-6R) engaged in trans-signalling. The pro-tumour functions of IL-6 are associated with STAT3, a major oncogenic transcription factor that triggers up-regulation of target genes responsible for tumour cell survival. IL-6 combined with TGF-β induces proliferation of pathogenic Th17 cells. The anti-tumour function of IL-6 is the promotion of anti-tumour immunity. IL-6 trans-signaling contributed to transmigration of lymphocytes in high endothelial venules (HEV). Dendritic cell (DC) secreted IL-6 in the lymph node influences the activation, distribution and polarisation of the immune response. Elevated serum levels of IL-6 and increased expression of IL-6 in tumour tissue are negative prognostic marker for patients' survival.

Non-Invasive Radiofrequency Field Treatment of 4T1 Breast Tumors Induces T-cell Dependent Inflammatory Response

Previous work using non-invasive radiofrequency field treatment (RFT) in cancer has demonstrated its therapeutic potential as it can increase intratumoral blood perfusion, localization of intravenously delivered drugs, and promote a hyperthermic intratumoral state. Despite the well-known immunologic benefits that febrile hyperthermia can induce, an investigation of how RFT could modulate the intra-tumoral immune microenvironment had not been studied. Thus, using an established 4T1 breast cancer model in immune competent mice, we demonstrate that RFT induces a transient, localized, and T-cell dependent intratumoral inflammatory response. More specifically we show that multi- and singlet-dose RFT promote an increase in tumor volume in immune competent Balb/c mice, which does not occur in athymic nude models. Further leukocyte subset analysis at 24, 48, and 120 hours after a single RFT show a rapid increase in tumoral trafficking of CD4+ and CD8+ T-cells 24 hours post-treatment. Additional serum cytokine analysis reveals an increase in numerous pro-inflammatory cytokines and chemokines associated with enhanced T-cell trafficking. Overall, these data demonstrate that non-invasive RFT could be an effective immunomodulatory strategy in solid tumors, especially for enhancing the tumoral trafficking of lymphocytes, which is currently a major hindrance of numerous cancer immunotherapeutic strategies.

A review of immune therapy in cancer and a question: can thermal therapy increase tumor response?

Immune therapy is a successful cancer treatment coming into its own. This is because checkpoint molecules, adoptive specific lymphocyte transfer and chimeric antigen T-cell (CAR-T) therapy are able to induce more durable responses in an increasing number of malignancies compared to chemotherapy. In addition, immune therapies are able to treat bulky disease, whereas standard cytotoxic therapies cannot treat large tumour burdens. Checkpoint inhibitor monoclonal antibodies are becoming widely used in the clinic and although more complex, adoptive lymphocyte transfer and CAR-T therapies show promise. We are learning that there are nuances to predicting the successful use of the checkpoint inhibitors as well as to specific-antigen adoptive and CAR-T therapies. We are also newly aware of a here-to-fore unrealised natural force, the status of the microbiome. However, despite better understanding of mechanisms of action of the new immune therapies, the best responses to the new immune therapies remain 20-30%. Likely the best way to improve this somewhat low response rate for patients is to increase the patient's own immune response. Thermal therapy is a way to do this. All forms of thermal therapy, from fever-range systemic thermal therapy, to high-temperature HIFU and even cryotherapy improve the immune response pre-clinically. It is time to test the immune therapies with thermal therapy in vivo to test for optimal timing of the combinations that will best enhance tumour response and then to begin to test the immune therapies with thermal therapy in the clinic as soon as possible.

The cryo-thermal therapy-induced IL-6-rich acute pro-inflammatory response promoted DCs phenotypic maturation as the prerequisite to CD4+ T cell differentiation

In our previous studies, a novel tumour therapeutic modality of the cryo-thermal therapy has been developed leading to long-term survival in 4T1 murine mammary carcinoma model. The cryo-thermal therapy induced the strong acute inflammatory response and IL-6 was identified in an acute profile. In this study, we found that the cryo-thermal therapy triggered robust acute inflammatory response with high expression of IL-6 locally and systemically. The phenotypic maturation of dendritic cells (DCs) was induced by acute IL-6 following the treatment. The mature DCs promoted CD4⁺ T cell differentiation. Moreover, the production of interferon γ (IFN γ) in the serum and CD4⁺ T cells were both abrogated by IL-6 neutralisation following the treatment. Our findings revealed that the cryo-thermal therapy-induced acute IL-6 played an important role in initiating the cascading innate and adaptive anti-tumour immune responses, resulting in CD4⁺ T cell differentiation. It would be interesting to investigate acute IL-6 as an early indicator in predicating tumour therapeutic effect.

It's Getting Hot in Here: Targeting Cancer Stem-like Cells with Hyperthermia

Cancer stem-like cells (CSCs) are a subset of cancer cells that are resistant to conventional radiotherapy and chemotherapy. As such, CSCs have been recognized as playing a large role in tumor initiation and recurrence. Although hyperthermia is broadly used in cancer treatment either alone or in combination with radio- or chemo-therapy, its potential to target CSCs is not well understood. In this review, we discuss different types of hyperthermia and potential mechanisms of action in cancer treatment, particularly in regards to killing CSCs.

Epidemiology and Cytokine Levels among Children with Nosocomial Multidrug-Resistant Acinetobacter baumannii Complex in a Tertiary Hospital of Eastern China

BACKGROUND AND AIM

The present study was aimed at assessing the characteristics of children with nosocomial multidrug-resistant Acinetobacter baumannii complex (MDR ABC) in a tertiary hospital of eastern China. MDR ABC poses a serious threat to public health. However, information on nosocomial MDR ABC in children is lacking.

METHOD

This study retrospectively reviewed the cases in a tertiary hospital of eastern China between January 1, 2011, and December 31, 2014 (excluding outpatients).

RESULTS

A total of 377 non-duplicated nosocomial ABC isolates were collected from various samples including 200 (53.1%) MDR ABC isolates. Moreover, 158 of the 200 MDR ABC isolates were collected from intensive care units (ICUs; MDR constituent ratios, 62.5%), while 98 of the 200 MDR ABC isolates were collected from children older than 1 year (MDR constituent ratios, 62.8%). Multivariate logistic analysis revealed that being in the surgical intensive care unit (SICU), prolonged hospital stay, surgical intervention, and mechanical ventilation were independent risk factors for MDR acquisition among children with nosocomial ABC. The interleukin (IL)-6 level of children with nosocomial MDR ABC was significantly lower than that of the children with nosocomial non-MDR ABC.

CONCLUSION

Nosocomial MDR ABC infection is a serious concern in pediatric patients. Being in the SICU, prolonged hospital stay, surgical intervention, and mechanical ventilation increased the risk of nosocomial MDR ABC. IL-6 might be involved in developing nosocomial MDR ABC among children.

Temperature matters! And why it should matter to tumor immunologists

A major goal of cancer immunology is to stimulate the generation of long-lasting, tumor antigen-specific immune responses that recognize and destroy tumor cells. This article discusses advances in thermal medicine with the potential to improve cancer immunotherapy. Accumulating evidence indicates that survival benefits are accorded to individuals who achieve an increase in body temperature (i.e. fever) following infection. Furthermore, accumulating evidence indicates that physiological responses to hyperthermia impact the tumor microenvironment through temperature-sensitive check-points that regulate tumor vascular perfusion, lymphocyte trafficking, inflammatory cytokine expression, tumor metabolism, and innate and adaptive immune function. Nevertheless, the influence of thermal stimuli on the immune system, particularly the antitum or immune response, remains incompletely understood. In fact, temperature is still rarely considered as a critical variable in experimental immunology. We suggest that more attention should be directed to the role of temperature in the regulation of the immune response and that thermal therapy should be tested in conjunction with immunotherapy as a multi-functional adjuvant that modulates the dynamics of the tumor microenvironment.

Fever and the thermal regulation of immunity: the immune system feels the heat

Fever is a cardinal response to infection that has been conserved in warm-blooded and cold-blooded vertebrates for more than 600 million years of evolution. The fever response is executed by integrated physiological and neuronal circuitry and confers a survival benefit during infection. In this Review, we discuss our current understanding of how the inflammatory cues delivered by the thermal element of fever stimulate innate and adaptive immune responses. We further highlight the unexpected multiplicity of roles of the pyrogenic cytokine interleukin-6 (IL-6), both during fever induction and during the mobilization of lymphocytes to the lymphoid organs that are the staging ground for immune defence. We also discuss the emerging evidence suggesting that the adrenergic signalling pathways associated with thermogenesis shape immune cell function.

The two faces of IL-6 in the tumor microenvironment

Within the tumor microenvironment, IL-6 signaling is generally considered a malevolent player, assuming a dark visage that promotes tumor progression. Chronic IL-6 signaling is linked to tumorigenesis in numerous mouse models as well as in human disease. IL-6 acts intrinsically on tumor cells through numerous downstream mediators to support cancer cell proliferation, survival, and metastatic dissemination. Moreover, IL-6 can act extrinsically on other cells within the complex tumor microenvironment to sustain a pro-tumor milieu by supporting angiogenesis and tumor evasion of immune surveillance. A lesser known role for IL-6 signaling has recently emerged in which it plays a beneficial role, presenting a fairer face that opposes tumor growth by mobilizing anti-tumor T cell immune responses to attain tumor control. Accumulating evidence establishes IL-6 as a key player in the activation, proliferation and survival of lymphocytes during active immune responses. IL-6 signaling can also resculpt the T cell immune response, shifting it from a suppressive to a responsive state that can effectively act against tumors. Finally, IL-6 plays an indispensable role in boosting T cell trafficking to lymph nodes and to tumor sites, where they have the opportunity to become activated and execute their cytotoxic effector functions, respectively. Here, we discuss the dual faces of IL-6 signaling in the tumor microenvironment; the dark face that drives malignancy, and the fairer aspect that promotes anti-tumor adaptive immunity.

Plasma membranes as heat stress sensors: from lipid-controlled molecular switches to therapeutic applications

The classic heat shock (stress) response (HSR) was originally attributed to protein denaturation. However, heat shock protein (Hsp) induction occurs in many circumstances where no protein denaturation is observed. Recently considerable evidence has been accumulated to the favor of the "Membrane Sensor Hypothesis" which predicts that the level of Hsps can be changed as a result of alterations to the plasma membrane. This is especially pertinent to mild heat shock, such as occurs in fever. In this condition the sensitivity of many transient receptor potential (TRP) channels is particularly notable. Small temperature stresses can modulate TRP gating significantly and this is influenced by lipids. In addition, stress hormones often modify plasma membrane structure and function and thus initiate a cascade of events, which may affect HSR. The major transactivator heat shock factor-1 integrates the signals originating from the plasma membrane and orchestrates the expression of individual heat shock genes. We describe how these observations can be tested at the molecular level, for example, with the use of membrane perturbers and through computational calculations. An important fact which now starts to be addressed is that membranes are not homogeneous nor do all cells react identically. Lipidomics and cell profiling are beginning to address the above two points. Finally, we observe that a deregulated HSR is found in a large number of important diseases where more detailed knowledge of the molecular mechanisms involved may offer timely opportunities for clinical interventions and new, innovative drug treatments. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.