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Background: Older patients with cancer have a higher risk for malnutrition and impaired quality of life (QoL). The present study aimed to investigate the relationship between malnutrition diagnosed according to the Global Leadership Initiative Malnutrition (GLIM) criteria and QoL across various tumor types, and to evaluate the combined prognostic value of malnutrition and QoL in predicting survival among older patients with cancer., Methods: This multicenter, observational cohort study included 5310 older patients with cancer and 2184 with malnutrition (moderate stage, n = 1023; severe stage, n = 1161). An empirical cumulative distribution curve was performed to illustrate the correlation between malnutrition and QoL. The primary objective was to investigate the association between malnutrition and QoL using logistic regression analysis. Survival analyses were performed to assess the combined prognostic value of malnutrition and QoL., Results: The median age of the patients (66.9% male, 33.1% female) was 70 years (interquartile range [IQR] 67-74 years) years. The median QoL score was highest in patients without malnutrition (91.88 [IQR 84.44-97.44]), followed by those with moderate (86.15 [IQR 76.18-93.85) and severe (82.31 [IQR 69.87-91.11]) malnutrition. Logistics regression revealed that the risk for developing impaired QoL increased 1.98 (95% confidence interval [CI] 1.64-2.38; P < 0.001) and 2.33 (95% CI 1.93-2.81; P < 0.001) times in patients with moderate and severe malnutrition, respectively. Kaplan-Meier curves showed that QoL in combination with GLIM criteria demonstrated a significant discriminative performance for survival and served as an independent prognostic factor among older patients with cancer, especially for lung and gastric cancers., Conclusions: Malnutrition diagnosed according to the GLIM criteria was a predictor of impaired QoL. Additionally, the combination of QoL and malnutrition demonstrated utility for predicting survival outcomes in older patients with cancer., (Copyright © 2024. Published by Elsevier Masson SAS.)

Herein, we developed a doxorubicin (Dox)-loaded and 4T1 cancer cell membrane-modified hydrogenated manganese oxide nanoparticles (mHMnO-Dox) to elicit systemic antitumor immune responses. The results revealed that mHMnO-Dox actively recognized tumor cells and then effectively delivered Dox into the cells. Upon entering tumor cells, the mHMnO-Dox underwent rapid degradation and abundant release of Mn 2+ and chemotherapeutic drugs. The released Mn 2+ not only catalysed a Fenton-type reaction to produce excessive reactive oxygen species (ROS) but also activated the cGAS-STING pathway to boost dendritic cell (DC) maturation. This process increased cytotoxic T lymphocyte infiltration as well as natural killer cell recruitment into the tumor site. In addition, the released Dox could contribute to a chemotherapeutic effect, while activating DC cells and subsequently intensifying immune responses through immunogenic cell death (ICD) of tumor cells. Consequently, the mHMnO-Dox suppressed the primary and distal tumor growth and inhibited tumor relapse and metastasis, as well as prolonged the lifespan of tumor-bearing mice. Thus, the mHMnO-Dox multimodally activated DC cells to demonstrate synergistic antitumor activity, which was mediated via the activation of the cGAS-STING signalling pathway to regulate tumor microenvironment, ICD-mediated immunotherapy and ROS-mediated CDT. These findings suggest the therapeutic potential of mHMnO-Dox in cancer immunotherapy. STATEMENT OF SIGNIFICANCE: A cancer cell membrane-camouflaged hydrogenated mesoporous manganese oxide (mHMnO) has been developed as a cGAS-STING agonist and ICD inducer. The mHMnO effectively induced abundance of ROS production in cancer cells, which caused cancer cell death and then promoted DC maturation via tumour-associated antigen presentation. Meanwhile, the mHMnO significantly activated cGAS-STING pathway to facilitate DC maturation and cytotoxic T lymphocyte infiltration as well as natural killer cell recruitment, which further enhanced tumour immune response. In addition, the combination of the mHMnO and Dox could synergistically promote tumour ICD and then multimodally induce DC maturation, achieving an enhanced CIT. Overall, this study provides a potential strategy to design novel immunologic adjuvant for enhanced CIT., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The formation of blood vessel system under a relatively higher Cu 2+ ion level is an indispensable precondition for tumor proliferation and migration, which was assisted in forming the tumor immune microenvironment. Herein, a copper ions nano-reaper (LMDFP) is rationally designed not only for chelating copper ions in tumors, but also for combination with photothermal therapy (PTT) to improve antitumor efficiency. Under 808 nm laser irradiation, the fabricated nano-reaper converts light energy into thermal energy to kill tumor cells and promotes the release of D-penicillamine (DPA) in LMDFP. Photothermal properties of LMDFP can cause tumor ablation in situ, which further induces immunogenic cell death (ICD) to promote systematic antitumor immunity. The released DPA exerts an anti-angiogenesis effect on the tumor through chelating copper ions, and inhibits the expression of programmed death ligand 1 (PD-L1), which synergizes with PTT to enhance antitumor immunity and inhibit tumor metastasis. Meanwhile, the nanoplatform can emit near-infrared-IIb (NIR-IIb) fluorescence under 980 nm excitation, which can be used to track the nano-reaper and determine the optimal time point for PTT. Thus, the fabricated nano-reaper shows powerful potential in inhibiting tumor growth and metastasis, and holds great promise for the application of copper nanochelator in precise tumor treatment., (© 2024. The Author(s).)

Chimeric antigen receptor (CAR)-T cell immunotherapy is approved in the treatment of hematological malignancies, but remains far from satisfactory in solid tumor treatment due to inadequate intra-tumor CAR-T cell infiltration. Herein, an injectable supramolecular hydrogel system, based on self-assembly between cationic polymer mPEG-PCL-PEI (PPP) conjugated with T cell targeting anti-CD3e f(ab')2 fragment and α-cyclodextrin (α-CD), is designed to load plasmid CAR (pCAR) with a T cell specific CD2 promoter, which successfully achieves in situ fabrication and effective accumulation of CAR-T cells at the tumor site in humanized mice models. More importantly, due to this tumor microenvironment reprogramming, secretion of cellular inflammatory cytokines (interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ)) or tumor killer protein granzyme B is significantly promoted, which reverses the immunosuppressive microenvironment and significantly enhances the intra-tumor CAR-T cells and cytotoxic T cells infiltration. To the best of the current knowledge, this is a pioneer report of using injectable supramolecular hydrogel for in situ reprogramming CAR-T cells, which might be beneficial for solid tumor CAR-T immunotherapy., (© 2023 Wiley-VCH GmbH.)

Cancers remain the leading cause of mortality worldwide. It is crucial to detect cancer at an early stage for improving survival rates. Biomarkers have precise implications for cancer progression. Here, we built a straightforward DNA probe system that could be activated by near-infrared light to detect dual miRNAs with a high specificity. This probe is built on the basis of upconversion nanoparticles, which could emit ultraviolet light and activate DNA probes adsorbed on the outer layer. The DNA probe system is remotely controlled through manipulation of the near-infrared (NIR) light, enabling simultaneous detection of dual miRNAs. The DNA nanosystem could be effectively endocytosed by cancer cells and reflect expression levels of dual miRNAs. Overall, this study demonstrates a promising remote-controlled DNA nanoplatform for the simultaneous detection of dual miRNAs, which has tremendous potential for precise cancer diagnostics and therapies.

Adoptive T-cell therapy against solid tumours is limited by the apoptosis resistance mechanisms of tumour cells and by the extracellular, immunosuppressive tumour microenvironment. Here we report a temperature-sensitive genome-editing nanodevice that can deliver a Cas9 editor with an external trigger which can be used to edit the genome of tumour cells to reduce resistance to apoptosis and modulate the tumour microenvironment via a mild heating trigger. After local or systemic delivery of Cas9, mild heating is induced by non-invasive near-infrared (NIR) light or focused ultrasound (FUS) to activate Cas9, which initiates simultaneous genome editing of HSP70 (HSPA1A) and BAG3 in tumour cells. This disrupts the apoptotic resistance machinery of the tumour cells against adoptive T cells. At the same time, an NIR- or FUS-induced mild thermal effect reshapes the extracellular tumour microenvironment by disrupting the physical barriers and immune suppression. This facilitates the infiltration of adoptive T cells and enhances their therapeutic activity. Mild thermal Cas9 delivery is demonstrated in different murine tumour models which mimic a range of clinical indications, including a tumour model based on humanized patient-derived xenografts. As a result, the non-invasive thermal delivery of Cas9 significantly enhances the therapeutic efficacies of tumour-infiltrating lymphocytes and chimeric antigen receptor T and shows potential for clinical application., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Chemodynamic therapy of cancer is limited by insufficient endogenous H 2 O 2 generation and acidity in the tumor microenvironment (TME). Herein, we developed a biodegradable theranostic platform (pLMOFePt-TGO) involving composite of dendritic organosilica and FePt alloy, loaded with tamoxifen (TAM) and glucose oxidase (GOx), and encapsulated by platelet-derived growth factor-B (PDGFB)-labeled liposomes, that effectively uses the synergy among chemotherapy, enhanced chemodynamic therapy (CDT), and anti-angiogenesis. The increased concentration of glutathione (GSH) present in the cancer cells induces the disintegration of pLMOFePt-TGO, releasing FePt, GOx, and TAM. The synergistic action of GOx and TAM significantly enhanced the acidity and H 2 O 2 level in the TME by aerobiotic glucose consumption and hypoxic glycolysis pathways, respectively. The combined effect of GSH depletion, acidity enhancement, and H 2 O 2 supplementation dramatically promotes the Fenton-catalytic behavior of FePt alloys, which, in combination with tumor starvation caused by GOx and TAM-mediated chemotherapy, significantly increases the anticancer efficacy of this treatment. In addition, T 2 -shortening caused by FePt alloys released in TME significantly enhances contrast in the MRI signal of tumor, enabling a more accurate diagnosis. Results of in vitro and in vivo experiments suggest that pLMOFePt-TGO can effectively suppress tumor growth and angiogenesis, thus providing an exciting potential strategy for developing satisfactory tumor theranostics., (© 2023. The Author(s).)

Immunotherapy has paved the way for the future of cancer therapy, but there are still significant challenges to be overcome, such as the occurrence of immune escape or suppression. Adenosine is essential in modulating the immune responses of immune cells and maintaining immune tolerance. Emerging adenosine pathway inhibitors are considered a breakthrough in cancer immunotherapy, with emphasis first being placed on the top-down blockade of adenosine signaling axis, followed by combination therapy. However, these therapeutic strategies rely on adenosine inhibitors, mainly small molecules or antibody proteins, which are limited by a single route of administration and off-target toxicity. Therefore, synergistic nanomedicine with accurate delivery targeting deeper tumors is focused on in preclinical studies. This review discusses how adenosine reshapes immunosuppressive microenvironments through its effects on immune cells, including lymphocytes and myeloid cells. Additionally, it will be the first discussion of a comprehensive strategy of biomaterials in modulating the adenosine signaling pathway, including inhibition of adenosine production, inhibition of adenosine binding to immune cells, and depletion of adenosine in the microenvironments. Furthermore, biomaterials integrating multiple therapeutic modalities with adenosine blocking are also discussed as a promising strategy for promoting cancer immunotherapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wei, Zhang, Zhao, Cheng, Xin and Ding.)

The application of chemodynamic therapy (CDT) for cancer is a serious challenge owing to the low efficiency of the Fenton catalyst and insufficient H 2 O 2 expression in cells. Herein, we fabricated a PDGFB targeting, biodegradable FePt alloy assembly for magnetic resonance imaging (MRI)-guided chemotherapy and starving-enhanced chemodynamic therapy for cancer using PDGFB targeting, pH-sensitive liposome-coated FePt alloys, and GOx (pLFePt-GOx). We found that the Fenton-catalytic activity of FePt alloys was far stronger than that of traditional ultrasmall iron oxide nanoparticle (UION). Upon entry into cancer cells, pLFePt-GOx nanoliposomes degraded into many tiny FePt alloys and released GOx owing to the weakly acidic nature of the tumor microenvironment (TME). The released GOx-mediated glucose consumption not only caused a starvation status but also increased the level of cellular H 2 O 2 and acidity, promoting Fenton reaction by FePt alloys and resulting in an increase in reactive oxygen species (ROS) accumulation in cells, which ultimately realized starving-enhanced chemodynamic process for killing tumor cells. The anticancer mechanism of pLFePt-GOx involved ROS-mediated apoptosis and ferroptosis, and glucose depletion-mediated starvation death. In the in vivo assay, the systemic delivery of pLFePt-GOx showed excellent antitumor activity with low biological toxicity and significantly enhanced T 2 -weighted magnetic resonance imaging (MRI) signal of the tumor, indicating that pLFePt-GOx can serve as a highly efficient theranostic tool for cancer. This work thus describes an effective, novel multi-modal cancer theranostic system., (© 2022. The Author(s).)

Therapeutic monoclonal antibodies (mAbs) blocking immune checkpoints have been mainly used as monotherapy. Recently, combination therapy targeting multiple immune checkpoints has recently been explored to increase anti-cancer efficacy. Particularly, a single molecule targeting more than one checkpoints has been investigated. As dual blocking of PD-1/PD-L1 and VEGF/VEGFR has demonstrated synergism in anti-tumor activities, we developed a novel bispecific antibody, termed HB0025, which is formed via fusing the domain 2 of vascular endothelial growth factor receptor 1 (VEGFR1D2) and anti-PD-L1 mAb by using mAb-Trap technology. HB0025 almost completely retains the binding affinities and the biological activities in-vitro when compared with the parent anti-PD-L1 mAb or VEGFR1D2 fusion protein. Preclinical data demonstrated that HB0025 was more effective in inhibiting cancer growth than anti PD-L1 mAb or VEGFR1D2 fusion protein. Thus, our bispecific antibody may bring about greater clinical benefits and broader indications., Competing Interests: Authors XCu, HJ, SC, SX, XL, WX, XCh, YF, XW, HY, YW, YZ XZ were employed by company Huabo Biopharma and authors LZ and XZ were employed by Huaota Biopharma. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cui, Jia, Xin, Zhang, Chen, Xia, Li, Xu, Chen, Feng, Wei, Yu, Wang, Zhan, Zhu and Zhang.)

The precise release of drugs is essential to improve cancer therapeutic efficacy. In this work, a tandem responsive strategy was developed based on a triple-layered metal-organic framework (MOF) hybrid. The MOF nanoprobe was stepwise fabricated with a telomerase-responsive inner, a pH-sensitive MOF filling and H 2 O 2 -responsive coordination complex shell of Fe 3+ and eigallocatechin gallate (EGCG). In the tumor microenvironment, the shell was dissociated by endogenous H 2 O 2 and simultaneously produced highly reactive hydroxyl radicals by a Fenton reaction. Meanwhile, the released EGCG could downregulate the expression of P-glycoprotein responsible for drug resistance. After the dissociation of the framework by protons, telomerase could trigger the release of the drug from the DNA duplex on the exposed inner shell. By integrating confined drug release, inhibited efflux pump and chemodynamic therapy, the all-in-one chemotherapy strategy was identified with enhanced therapeutic efficacy in drug-resistant cancer cells., (© 2021 Wiley-VCH GmbH.)

Although photodynamic therapy (PDT) has been an attractive strategy for several cancer treatments in the clinical setting, PDT efficacy is attenuated by consumption of oxygen. To address this photodynamic issue, we adopted a phototherapy-chemotherapy combination strategy based on targeted delivery of the near-infrared photosensitizer indocyanine green (ICG), photothermal conversion agent polydopamine (PDA), and tirapazamine (TPZ), a hypoxia-activated prodrug. Under laser irradiation, ICG consumption of oxygen and aggravated hypoxia in tumor sites can activate TPZ to damage DNA. In parallel, ICG produces reactive oxygen species which work in synergy with PDA to enhance phototherapeutic efficiency. Herein, hybrid CaCO 3 /TPGS nanoparticles delivering ICG, PDA, and TPZ (ICG-PDA-TPZ NPs) were designed for effective and safe cancer therapy. ICG-PDA-TPZ NPs showed significantly improved cellular uptake and accumulation in tumors. Furthermore, we demonstrated that ICG-PDA-TPZ NPs showed intensive photodynamic and photothermal effects in vitro and in vivo, which synergized with TPZ in subcutaneous U87 malignant glioma growth and orthotopic B16F10 tumor inhibition, with negligible side effects. Thus, ICG-PDA-TPZ NPs could be an effective strategy for improvement of PDT.

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

Harnessing immune system to treat cancer requires simultaneous generation of tumor-specific CTLs and curtailment of tumor immunosuppressive environment. Here, we developed an immunotherapeutic regimen capable of eliminating large established mouse tumors using HMGN1, a DC-activating TLR4 agonist capable of inducing anti-tumor immunity. Intratumoral delivery of HMGN1 with low dose of Cytoxan cured mice bearing small (∅ ≈ 0.5 cm), but not large (∅ ≈ 1.0 cm) CT26 tumors. Screening for activators capable of synergizing with HMGN1 in activating DC identified R848. Intratumoral delivery of HMGN1 and R848 plus Cytoxan eradicated large established CT26 tumors. The resultant tumor-free mice were resistant to subsequent challenge with CT26, indicating the generation of CT26-specific protective immunity. This immunotherapeutic regimen caused homing of tumor-infiltrating DC to draining lymph nodes and increased infiltration of T cells into tumor tissues. Cytoxan in this regimen could be replaced by anti-CTLA4) or anti-PD-L1. Importantly, this immunotherapeutic regimen was also curative for large established mouse Renca and EG7 tumors. Thus, we have developed a curative therapeutic vaccination regimen dubbed 'TheraVac' consisting of HMGN1 and R848 plus a checkpoint inhibitor, that can, without using exogenous tumor-associated antigen(s), eliminate various large tumors and induce tumor-specific immunity.

A "relay drug delivery" system based on two distinct modules, which is composed of a signal transmission nanocarrier A (NC A ) that can specifically induce tumor blood vessel inflammation generation and an execution biomimetic nanocarrier B (NC B ) that can accumulate at the tumor site by receiving the broadcasting signals generated by NC A , is developed for amplifying active tumor targeting signal and enhancing antitumor therapy., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Human cancers are endowed with sustained vascularization capability, and their growth, invasion, and metastasis are vascularization dependent. Recently, accumulated body of evidence suggests that endothelial progenitor cells (EPCs) can support vasculogenesis and induce angiogenesis through paracrine mechanisms. In addition, numerous clinical studies have revealed the increase in the number of EPCs in the peripheral blood of cancer patients and demonstrated the correlation of circulating EPCs (CEPCs) with the clinical outcomes. This review highlights current enrichment procedures and methods for the detection of CEPCs and different biomarkers to identify CEPCs as well as the functions of EPCs in tumor vascularization. Furthermore, we systematically review available studies on the clinical relevance of CEPCs in cancer patients to explore the potential diagnostic and prognostic values of CEPCs. Although several contrasting results exist, CEPCs can conceivably serve as a promising biomarker for the early diagnosis, prognosis prediction, and treatment response indication in the future. Additionally, further well-designed clinical studies with larger sample size and unique, specific enumeration procedures are warranted to achieve further insight into the clinical implications of CEPCs.

Limited penetration of antineoplastic agents is one of the contributing factors for chemotherapy failure of many solid tumors. In order to enhance drug penetration into solid cancer, especially, into the avascular regions inside tumors, we proposed cyclic RGD peptide functionalized PEGylated poly(trimethylene carbonate) nanoparticles (c(RGDyK)-NP). By integrin-mediated transcytosis and enhanced drug permeation, c(RGDyK)-NP could access the neoplastic cells distant from blood vessels, and consequently, avoiding the capability of cancer regeneration from these tumor cells. In the present study, the solid tumor penetration, homing specificity and anticancer efficacy were evaluated both on the ex vivo 3D tumor spheroids and on the subcutaneous xenograft mice model. In comparison with conventional nanoparticles (NP/PTX) and Taxol, c(RGDyK)-NP/PTX showed the strongest penetration and accumulation into 3D tumor spheroids, a marked tumor-homing specificity in vivo and the greatest tumor growth inhibitory effect in vitro and in vivo. Histochemistry analysis revealed that no obvious histopathological abnormalities or lesions were observed in major organs after intravenous administration with the treatment doses. In conclusion, cyclic RGD peptide-conjugated PEG-PTMC nanoparticle could facilitate drug penetration and accumulation in tumor tissues and may be a promising vehicle for enhancing the chemotherapy of solid cancers., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Cyclic RGD peptide-decorated polymeric micellar-like nanoparticles (MNP) based on PEGylated poly (trimethylene carbonate) (PEG-PTMC) were prepared for active targeting to integrin-rich cancer cells. An amphiphilic diblock copolymer, α-carboxyl poly (ethylene glycol)-poly (trimethylene carbonate) (HOOC-PEG-PTMC), was synthesized by ring-opening polymerization. The c(RGDyK) ligand, a cyclic RGD peptide that can bind to the integrin proteins predominantly expressed on the surface of tumor cells with high affinity and specificity, was conjugated to the NHS-Activated PEG terminus of the copolymer. The c(RGDyK)-functionalized PEG-PTMC micellar nanoparticles encapsulating PTX (c(RGDyK)-MNP/PTX) was fabricated by the emulsion/solvent evaporation technique and characterized in terms of morphology, size and zeta potential. Cellular uptake of c(RGDyK)-MNP/PTX was found to be higher than that of MNP/PTX due to the integrin protein-mediated endocytosis effect. In vitro cytotoxicity, cell apoptosis and cell cycle arrest studies also revealed that c(RGDyK)-MNP/PTX was more potent than those of MNP/PTX and Taxol. Pharmacokinetic study in rats demonstrated that the polymeric micellar nanoparticles significantly enhanced the bioavailability of PTX than Taxol. In vivo multispectral fluorescent imaging indicated that c(RGDyK)-MNP/PTX had high specificity and efficiency in tumor active targeting. Therefore, the results demonstrated that c(RGDyK)-decorated PEG-PTMC MNP developed in this study could be a potential vehicle for delivering hydrophobic chemotherapeutic agents to integrin-rich tumors., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Interactions between tumor and immune cells either enhance or inhibit cancer progression. We show here that Stat3 signaling within the tumor microenvironment induces a procarcinogenic cytokine, IL-23, while inhibiting a central anticarcinogenic cytokine, IL-12, thereby shifting the balance of tumor immunity toward carcinogenesis. Stat3 induces expression of IL-23, which is mainly produced by tumor-associated macrophages, via direct transcriptional activation of the IL-23/p19 gene. Furthermore, Stat3 inhibits NF-kappaB/c-Rel-dependent IL-12/p35 gene expression in tumor-associated dendritic cells. Tumor-associated regulatory T cells (Tregs) express IL-23 receptor, which activates Stat3 in this cell type, leading to upregulation of the Treg-specific transcription factor Foxp3 and the immunosuppressive cytokine IL-10. These results demonstrate that Stat3 promotes IL-23-mediated procarcinogenic immune responses while inhibiting IL-12-dependent antitumor immunity.

Despite adequately expressing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptors DR4/DR5, malignant cells are frequently refractory to the cytotoxic effect of this apoptosis-inducing ligand. The susceptibility of cancer cells to TRAIL can be potentiated by cisplatin (CDDP). This study was designed to evaluate the ability of cisplatin to enhance the cytotoxic effect of TRAIL gene therapy using the recombinant adenovirus-mediated tumor-selective expression of membrane-bound green fluorescence protein (GFP)-TRAIL fusion protein (AdVgTRAIL) on thoracic cancer cells and to elucidate the putative mechanisms responsible for this synergistic combination effect. While causing little death of cultured thoracic cancer cells by itself, AdVgTRAIL in combination with CDDP, on the other hand, mediated profound supra-additive cytotoxicity and apoptosis via a strong bystander effect. CDDP/AdVgTRAIL-induced cytotoxicity was completely abrogated either by the pancaspase inhibitor zVAD-fmk or by the selective caspase 9 inhibitor or by transient knockdown of caspase 9 by siRNA, indicating that this process was caspase-mediated and mitochondria-dependent. This was confirmed by the observation that Bcl2 overexpression protected the cells from combination-induced cytotoxicity. Robust activation of caspase 8 activity in combination-treated cells was blocked by overexpression of Bcl2, indicating that caspase 8 activation was secondary to the mitochondria-mediated amplification feedback loop. Combining CDDP with AdVgTRAIL greatly enhances its tumoricidal efficacy in cultured thoracic cancer cells in vitro. The two agents interact to mediate profound activation of caspase cascade via recruitment of the mitochondria and positive feedback loop. The CDDP/AdVgTRAIL combination also exhibits a strong antitumor effect in in vivo animal model of human cancer xenografts.

The CX3C chemokine fractalkine (CX3CL1) exists as both a membrane-bound form promoting firm cell-cell adhesion and a soluble form chemoattracting leukocytes expressing its receptor CX3CR1. When adenoviral vector expressing mouse fractalkine (AdFKN) was transduced to the tumor cells, fractalkine was expressed as both membrane-bound form on the tumor cells and soluble form in the supernatant in vitro. Intratumoral injection of AdFKN (1 x 10(9)PFU/tumor) into C26 and B16F10 tumors resulted in marked reduction of tumor growth compared to control (C26: 86.5%, p<0.001; B16F10: 85.5%, p<0.001). Histological examination of tumor tissues revealed abundant infiltration of NK cells, dendritic cells, and CD8(+) T lymphocytes 3 and/or 6 days after treatment with AdFKN. Splenocytes from mice treated by AdFKN developed tumor-specific cytotoxic T cells, and thereby protected from rechallenging with parental tumor cells. Antitumor effects by AdFKN were completely abrogated in both NK cell-depleted mice and CD8(-/-) mice, and partially blocked in CD4(-/-) mice. These data indicated that fractalkine mediates antitumor effects by both NK cell-dependent and T cell-dependent mechanisms. This study suggests that fractalkine can be a suitable candidate for immunogene therapy of cancer because fractalkine induces both innate and adaptive immunity.

Studies have revealed that human adenovirus-encoded E1A protein promotes cell proliferation through the targeted interaction with cellular proteins that act as key negative regulators of cell growth. The targets of E1A protein include the retinoblastoma tumor suppressor protein (pRb). Because p202, an interferon (IFN)-inducible murine protein (52-kDa), negatively regulates cell growth in part through the pRb/E2F pathway, we tested whether the p202 is a target of the adenovirus-encoded E1A protein for functional inactivation. Here we report that the expression of E1A protein overcame p202-mediated inhibition of cell growth and this correlated with an alleviation of p202-mediated inhibition of the transcriptional activity of E2F. Furthermore, E1A protein relieved p202-mediated inhibition of the specific DNA-binding activity of E2F complexes, including those containing the pocket proteins. Additionally, the E1A protein bound to p202 both in vitro and in vivo and a deletion of four amino acids in the conserved region 2 (CR2) of E1A protein significantly reduced the binding of E1A to p202. Interestingly, ectopic expression of p202 under reduced serum conditions significantly reduced E1A-mediated apoptosis. Taken together, our observations provide support to the idea that the p202 and adenovirus E1A protein functionally counteract each other and E1A protein targets p202 to promote cell proliferation.