Cancer. Awakening immunity

A minimalist multifunctional nano-prodrug for drug resistance reverse and integration with PD-L1 mAb for enhanced immunotherapy of hepatocellular carcinoma

Clinical treatment of hepatocellular carcinoma (HCC) with 5-fluorouracil (5-FU), the primary anticancer agent, remains unsatisfactory due to the glutathione (GSH)-associated drug resistance and immunosuppressive microenvironment of HCC. To develop a facile yet robust strategy to overcome 5-FU resistance for enhanced immunotherapy treatment of HCC via all dimensional GSH exhaustion, we report in this study construction of a minimalist prodrug consisting of 5-FU linked to an indoleamine-(2,3)-dioxygenase (IDO) inhibitor (IND) via a disulfide bridge, FU-SS-IND that can further self-assemble into stabilized nanoparticles, FU-SS-IND NPs. Specifically, besides the disulfide linker-induced GSH exhaustion, IND inhibits GSH biosynthesis and enhances the effector function of T cells for turning a "cold" tumor to a "hot" one, which synergistically achieving a tumor inhibition rate (TIR) of 92.5% in a 5-FU resistant mice model. Most importantly, FU-SS-IND NPs could upregulate programmed death ligand 1 (PD-L1) expression on the surface of tumor cells, which enables facile combination with immune checkpoint blockade (ICB) for a ultimate prolonged survival lifetime of 5-FU-resistant tumors-bearing mice. Overall, the minimalist bioreducible nano-prodrug developed herein demonstrates great translatable potential for efficiently reversing drug resistance and enhancing immunotherapy of HCC.

The reactive stroma response regulates the immune landscape in prostate cancer

Prostate cancer remains the most commonly diagnosed and the second leading cause of cancer-related deaths in men in the United States. The neoplastic transformation of prostate epithelia, concomitant with modulations in the stromal compartment, known as reactive stromal response, is critical for the growth, development, and progression of prostate cancer. Reactive stroma typifies an emergent response to disrupted tissue homeostasis commonly observed in wound repair and pathological conditions such as cancer. Despite the significance of reactive stroma in prostate cancer pathobiology, our understanding of the ontogeny, phenotypic and functional heterogeneity, and reactive stromal regulation of the immune microenvironment in prostate cancer remains limited. Traditionally characterized to have an immunologically "cold" tumor microenvironment, prostate cancer presents significant challenges for advancing immunotherapy compared to other solid tumors. This review explores the detrimental role of reactive stroma in prostate cancer, particularly its immunomodulatory function. Understanding the molecular characteristics and dynamic transcriptional program of the reactive stromal populations in tandem with tumor progression could offer insights into enhancing immunotherapy efficacy against prostate cancer.

Case Report: Exploration of changes in serum immunoinflammation-related protein complexes of patients with metastatic breast cancer

Patients with advanced breast cancer are difficult to treat and have poor prognosis. At present, the commonly used methods to monitor the disease progression of breast cancer are imaging examinations such as breast ultrasound, mammography and peripheral blood tumor markers such as carcinoembryonic antigen (CEA) and carbohydrate antigen 15-3 (CA15-3). However, none of them can detect tumor progression at an early stage. Serum immunoinflammation-related protein complexes (IIRPCs) showed potential to indicate cancer progression. Therefore, we attempted to monitor the level of IIRPCs in peripheral blood of patients with metastatic breast cancer and compare it with patients' treatment and disease progression, and here we performed case reports of two of them.

Ligustilide Inhibits Tumor Angiogenesis by Downregulating VEGFA Secretion from Cancer-Associated Fibroblasts in Prostate Cancer via TLR4

CAFs secrete VEGFA in the tumor microenvironment to induce angiogenesis and promote tumor growth. The downregulation of VEGFA secretion from CAFs helps block angiogenesis and exerts an anti-tumor effect. In vivo experiments showed that the angiogenesis of the tumor-bearing mice in the ligustilide group was significantly reduced. The results of MTT, tube formation, Transwell and scratch experiments showed that ligustilide did not affect the proliferation of HUVECs in a certain concentration range (<60 μM), but it inhibited the proliferation, tube formation and migration of HUVECs induced by CAFs. At this concentration, ligustilide did not inhibit CAF proliferation. The qPCR and WB results revealed that ligustilide downregulated the level of VEGFA in CAFs via the TLR4-ERK/JNK/p38 signaling pathway, and the effect was attenuated by blockers of the above molecules. Ligustilide also downregulated the autocrine VEGFA of HUVECs induced by CAFs, which inhibited angiogenesis more effectively. In addition, ligustilide inhibited glycolysis and HIF-1 expression in CAFs. Overall, ligustilide downregulated the VEGFA level in CAFs via the TLR4-ERK/JNK/p38 signaling pathway and inhibited the promotion of angiogenesis. This study provides a new strategy for the anti-tumor effect of natural active molecules, namely, blockade of angiogenesis, and provides a new candidate molecule for blocking angiogenesis in the tumor microenvironment.

FAPI-04 PET/CT Using [18F]AlF Labeling Strategy: Automatic Synthesis, Quality Control, and In Vivo Assessment in Patient

⁶⁸Ga labeled FAPI is the current standard for FAPI-PET, but its batch activity is limited. [¹⁸F]AlF-NOTA-FAPI-04 is a promising alternative combining the advantages of a chelator-based radiolabeling method with the unique properties of fluorine-18. The objective of this study was to develop a quick automatic method for synthesis of [¹⁸F]AlF-NOTA-FAPI-04 using a AllinOne synthesis system, and perform PET imaging with [¹⁸F]AlF-NOTA-FAPI-04 on patients. [¹⁸F]AlF-NOTA-FAPI-04 was produced, and its quality control was conducted by HPLC equipped with a radioactive detector. [¹⁸F]AlF-NOTA-FAPI-04 PET/CT imaging was performed in normal BALB/c mice (n = 3) and 4T1 breast cancer models (n = 3) to determine its biodistribution. Then [¹⁸F]AlF-NOTA-FAPI-04 and ¹⁸F-fluorodeoxyglucose (FDG) PET/CT imaging were performed in an invasive ductal carcinoma patient (female, 54 years old). The synthesis time of [¹⁸F]AlF-NOTA-FAPI-04 was about 25 min, and the radiochemical yield was 26.4 ± 1.5% (attenuation correction, n = 10). The radiochemical purity was above 99.0% and was above 98.0% after 6 h. The product was colorless transparent solution with pH value of 7.0-7.5, and the specific activity was 49.41 ± 3.19 GBq/μmol. PET/CT imaging in mice showed that physiological uptake of [¹⁸F]AlF-NOTA-FAPI-04 was mainly in the biliary system and bladder, and [¹⁸F]AlF-NOTA-FAPI-04 highly concentrated in tumor xenografts. PET/CT imaging in the patient showed that [¹⁸F]AlF-NOTA-FAPI-04 obtained high tumor background ratio (TBR) value of 8.44 in segment V and VI, while TBR value was 2.55 by ¹⁸F-FDG. [¹⁸F]AlF-NOTA-FAPI-04 could be synthesized with high radiochemical yield and batch production by AllinOne module and show excellent diagnosis performance in cancer patients.

Antitumor immunity targeting fibroblast activation protein-α in a mouse Lewis lung carcinoma model

The tumor stromal microenvironment is an integral part of the occurrence and development of tumor. Cancer-associated fibroblasts (CAFs) are a key component of most tumor stromal microenvironments. The present study aimed to investigate the use of CAFs-targeted immunotherapy to fibroblast activation protein-α (FAP-α) expressed in CAFs. Recombinant adenoviral vectors containing the mouse FAP-α cDNA (rAd-FAP-α) were constructed. C57BL/6 mice were immunized with rAd-FAP-α infected dendritic cells (DCs) against FAP-α, which is overexpress in CAFs. The results demonstrated that mice vaccinated with rAd-FAP-α DCs gave rise to potent FAP-α-specific cytotoxic T lymphocytes capable of lysing Lewis lung cancer (LLC) CAFs. Furthermore, mice vaccinated with rAd-FAP-α-transduced DCs induced an effective therapeutic or protective antitumor immunity to LLC in a subcutaneous model, and prolonged overall survival time compared with mice vaccinated with the control recombinant adenovirus-transduced DCs (rAd-c DCs) or DCs alone. The results of the present study suggested that FAP-α, which is preferentially expressed in CAFs, may be considered as a potential target for killing or destroying CAFs within the tumor stromal microenvironment, and may be exploited to develop immunogenic tumor vaccines.

MPSSS impairs the immunosuppressive function of cancer-associated fibroblasts via the TLR4-NF-κB pathway

The polysaccharides MPSSS was extracted from Lentinus edodes and has been reported to effectively inhibit tumor growth and eliminate the function of myeloid-derived immune suppressor cell-mediated T cell inhibition, thus improving the efficacy of cancer therapy. The exploration of how MPSSS affects the functions of cancer-associated fibroblasts (CAFs) will provide a new perspective for understanding the antitumor effects of MPSSS. In the present study, prostate CAFs were selected as target cells to study whether MPSSS affected cell proliferation and function. The results showed that MPSSS did not directly inhibit the growth of prostate CAFs but interfered with CAF-mediated T cell inhibition and affected the immunosuppressive function of prostate CAFs. Mechanistic studies were further performed and showed that MPSSS activated key node proteins in the NF-κB pathway that were dependent on MyD88, and a TLR4 inhibitor blocked the changes in these proteins and the effect of MPSSS. We hypothesize that MPSSS can activate the MyD88-dependent TLR4-NF-κB signaling pathway to change the function of CAFs. In conclusion, these results demonstrate that MPSSS can not only effectively inhibit the growth of prostate cancer as we previously reported but also alter the function of prostate CAFs by activating the TLR4-NF-κB pathway, providing a new strategy for the comprehensive treatment of tumors.

Overexpression of interleukin-35 in intrahepatic cholangiocarcinoma is a prognostic indicator after curative resection

Interleukin‐35 (IL‐35) is implicated in tumorigenesis, but its exact impact on intrahepatic cholangiocarcinoma (ICC) is not clear. The aim of the present study was to explore the specific effect of IL‐35 on patient prognosis. Additionally, we formulated an effective prognostic nomogram for ICC patients after curative resection. Immunohistochemistry was applied to explore IL‐35 expression as well as IL‐35 receptor (IL‐35R) in 102 ICC patients. Results showed that IL‐35 was highly expressed in ICC tumor tissues and was positively associated with lymph node metastasis (LNM), TNM stage and vascular invasion and was an independent prognostic factor for patients' overall survival (OS) and recurrence‐free survival (RFS). High expression of IL‐35R (gp130 and IL‐12Rβ2) was also observed in ICC cancer tissues, but only gp130 was an independent prognostic factor for OS and RFS and was indispensable in IL‐35‐mediated ICC clinical prognosis. The nomogram comprising carcinoembryonic antigen, LNM, IL‐35 and gp130 expression achieved better predictive accuracy compared with TNM stage for OS. Our data support that high IL‐35 expression correlates with ICC aggressiveness and emerges as a valuable biomarker for evaluating ICC progression and prognosis in clinical work.

Pericyte-targeting prodrug overcomes tumor resistance to vascular disrupting agents

Blood vessels in the tumor periphery have high pericyte coverage and are resistant to vascular disrupting agents (VDAs). VDA treatment resistance leads to a viable peripheral tumor rim that contributes to treatment failure and disease recurrence. Here, we provide evidence to support a hypothesis that shifting the target of VDAs from tumor vessel endothelial cells to pericytes disrupts tumor peripheral vessels and the viable rim, circumventing VDA treatment resistance. Through chemical engineering, we developed Z-GP-DAVLBH (from the tubulin-binding VDA desacetylvinblastine monohydrazide [DAVLBH]) as a prodrug that can be selectively activated by fibroblast activation protein α (FAPα) in tumor pericytes. Z-GP-DAVLBH selectively destroys the cytoskeleton of FAPα-expressing tumor pericytes, disrupting blood vessels both within the core and around the periphery of tumors. As a result, Z-GP-DAVLBH treatment eradicated the otherwise VDA-resistant tumor rim and led to complete regression of tumors in multiple lines of xenografts without producing the drug-related toxicity that is associated with similar doses of DAVLBH. This study demonstrates that targeting tumor pericytes with an FAPα-activated VDA prodrug represents a potential vascular disruption strategy in overcoming tumor resistance to VDA treatments.

Fibroblast activation protein is dispensable in the anti-influenza immune response in mice

Fibroblast activation protein alpha (FAP) is a unique dual peptidase of the S9B serine protease family, being capable of both dipeptidyl peptidase and endopeptidase activities. FAP is expressed at low level in healthy adult organs including the pancreas, cervix, uterus, submaxillary gland and the skin, and highly upregulated in embryogenesis, chronic inflammation and tissue remodelling. It is also expressed by cancer-associated stromal fibroblasts in more than 90% of epithelial tumours. FAP has enzymatic and non-enzymatic functions in the growth, immunosuppression, invasion and cell signalling of tumour cells. FAP deficient mice are fertile and viable with no gross abnormality, but little data exist on the role of FAP in the immune system. FAP is upregulated in association with microbial stimulation and chronic inflammation, but its function in infection remains unknown. We showed that major populations of immune cells including CD4+ and CD8+ T cells, B cells, dendritic cells and neutrophils are generated and maintained normally in FAP knockout mice. Upon intranasal challenge with influenza virus, FAP mRNA was increased in the lungs and lung-draining lymph nodes. Nonetheless, FAP deficient mice showed similar pathologic kinetics to wildtype controls, and were capable of supporting normal anti-influenza T and B cell responses. There was no evidence of compensatory upregulation of other DPP4 family members in influenza-infected FAP-deficient mice. FAP appears to be dispensable in anti-influenza adaptive immunity.

A whole-cell tumor vaccine modified to express fibroblast activation protein induces antitumor immunity against both tumor cells and cancer-associated fibroblasts

Cancer-associated fibroblasts (CAFs) are common components of the tumor-suppressive microenvironment, and are a major determinant of the poor outcome of therapeutic vaccination. In this study, we modified tumor cells to express the fibroblast activation protein (FAP), which is highly expressed by CAFs, to potentially improve whole-cell tumor vaccines by targeting both tumor cells and CAFs. Tumor cells were transfected with murine FAP plasmids bearing the cationic lipid DOTAP. Its antitumor effects were investigated in three established tumor models. Vaccination with tumor cells expressing FAP eliminated solid tumors and tumors resulting from hematogenous dissemination. This antitumor immune response was mediated by CD8+ T cells. Additionally, we found that CAFs were significantly reduced within the tumors. Furthermore, this vaccine enhanced the infiltration of CD8+ T lymphocytes, and suppressed the accumulation of immunosuppressive cells in the tumor microenvironment. Our results indicated that the FAP-modified whole-cell tumor vaccine induced strong antitumor immunity against both tumor cells and CAFs and reversed the immunosuppressive effects of tumors by decreasing the recruitment of immunosuppressive cells and enhancing the recruitment of effector T cells. This conclusion may have important implications for the clinical use of genetically modified tumor cells as cancer vaccines.

Preoperative neutrophil-to-lymphocyte ratio predicts recurrence of patients with single-nodule small hepatocellular carcinoma following curative resection: a retrospective report

BACKGROUND

Preoperative neutrophil-to-lymphocyte ratio (NLR) has been identified as a predictor for the recurrence of hepatocellular carcinoma (HCC), but the cut-off of NLR is inconsistent in various studies. Thus, we detected the prognostic value of preoperative NLR in the single-nodule small HCC (SHCC) patients using X-tile for cutpoint.

METHODS

Between January 2007 and December 2010, a total of 222 single-nodule SHCC patients underwent curative resection and were examined for the prognostic roles of preoperative NLR by X-tile.

RESULTS

In this study, all patients were divided into the low-NLR subgroup (NLR ≤ 2.1) and the high-NLR subgroup (NLR > 2.1) by X-tile. Preoperative NLR showed predictive value for time to recurrence (TTR) and overall survival (OS). Moreover, NLR was associated with total bilirubin, white blood cell counts, and HBsAg, respectively (P = 0.012, <0.001, and 0.011, respectively). Especially, NLR could discriminate the outcome of patients in the subgroup with alpha-fetoprotein (AFP) levels of ≤400 ng/mL. Importantly, postoperative transcatheter arterial chemoembolization (TACE) had close relationship with OS (P = 0.001) and TTR (P ≤ 0.001).

CONCLUSIONS

Therefore, this study indicates that preoperative NLR, divided by X-tile for the cutpoint, is a simple prognostic marker for the patients with single-nodule SHCC after curative resection.

Strategies for modern biomarker and drug development in oncology

Technological advancements in the molecular characterization of cancers have enabled researchers to identify an increasing number of key molecular drivers of cancer progression. These discoveries have led to multiple novel anticancer therapeutics, and clinical benefit in selected patient populations. Despite this, the identification of clinically relevant predictive biomarkers of response continues to lag behind. In this review, we discuss strategies for the molecular characterization of cancers and the importance of biomarkers for the development of novel antitumor therapeutics. We also review critical successes and failures in oncology, and detail the lessons learnt, which may aid in the acceleration of anticancer drug development and biomarker discovery.

Inter-cellular signaling network reveals a mechanistic transition in tumor microenvironment

We conducted inter-cellular cytokine correlation and network analysis based upon a stochastic population dynamics model that comprises five cell types and fifteen signaling molecules inter-connected through a large number of cell-cell communication pathways. We observed that the signaling molecules are tightly correlated even at very early stages (e.g. the first month) of human glioma, but such correlation rapidly diminishes when tumor grows to a size that can be clinically detected. Further analysis suggests that paracrine is shown to be the dominant force during tumor initiation and priming, while autocrine supersedes it and supports a robust tumor expansion. In correspondence, the cytokine correlation network evolves through an increasing to decreasing complexity. This study indicates a possible mechanistic transition from the microenvironment-controlled, paracrine-based regulatory mechanism to self-sustained rapid progression to fetal malignancy. It also reveals key nodes that are responsible for such transition and can be potentially harnessed for the design of new anti-cancer therapies.

Contribution of bone marrow derived cells to the pancreatic tumor microenvironment

Pancreatic cancer is a complex, aggressive, and heterogeneous malignancy driven by the multifaceted interactions within the tumor microenvironment. While it is known that the tumor microenvironment accommodates many cell types, each playing a key role in tumorigenesis, the major source of these stromal cells is not well-understood. This review examines the contribution of bone marrow-derived cells (BMDC) to pancreatic carcinogenesis, with respect to their role in constituting the tumor microenvironment. In particular, their role in supporting fibrosis, immunosuppression, and neovascularization will be discussed.

In silico experimentation of glioma microenvironment development and anti-tumor therapy

Tumor cells do not develop in isolation, but co-evolve with stromal cells and tumor-associated immune cells in a tumor microenvironment mediated by an array of soluble factors, forming a complex intercellular signaling network. Herein, we report an unbiased, generic model to integrate prior biochemical data and the constructed brain tumor microenvironment in silico as characterized by an intercellular signaling network comprising 5 types of cells, 15 cytokines, and 69 signaling pathways. The results show that glioma develops through three distinct phases: pre-tumor, rapid expansion, and saturation. We designed a microglia depletion therapy and observed significant benefit for virtual patients treated at the early stages but strikingly no therapeutic efficacy at all when therapy was given at a slightly later stage. Cytokine combination therapy exhibits more focused and enhanced therapeutic response even when microglia depletion therapy already fails. It was further revealed that the optimal combination depends on the molecular profile of individual patients, suggesting the need for patient stratification and personalized treatment. These results, obtained solely by observing the in silico dynamics of the glioma microenvironment with no fitting to experimental/clinical data, reflect many characteristics of human glioma development and imply new venues for treating tumors via selective targeting of microenvironmental components.

Modulation of tumor tolerance in primary central nervous system malignancies

Central nervous system tumors take advantage of the unique immunology of the CNS and develop exquisitely complex stromal networks that promote growth despite the presence of antigen-presenting cells and tumor-infiltrating lymphocytes. It is precisely this immunological paradox that is essential to the survival of the tumor. We review the evidence for functional CNS immune privilege and the impact it has on tumor tolerance. In this paper, we place an emphasis on the role of tumor-infiltrating myeloid cells in maintaining stromal and vascular quiescence, and we underscore the importance of indoleamine 2,3-dioxygenase activity as a myeloid-driven tumor tolerance mechanism. Much remains to be discovered regarding the tolerogenic mechanisms by which CNS tumors avoid immune clearance. Thus, it is an open question whether tumor tolerance in the brain is fundamentally different from that of peripheral sites of tumorigenesis or whether it simply stands as a particularly strong example of such tolerance.

Recruitment and activation of pancreatic stellate cells from the bone marrow in pancreatic cancer: a model of tumor-host interaction

BACKGROUND AND AIMS

Chronic pancreatitis and pancreatic cancer are characterised by extensive stellate cell mediated fibrosis, and current therapeutic development includes targeting pancreatic cancer stroma and tumor-host interactions. Recent evidence has suggested that circulating bone marrow derived stem cells (BMDC) contribute to solid organs. We aimed to define the role of circulating haematopoietic cells in the normal and diseased pancreas.

METHODS

Whole bone marrow was harvested from male β-actin-EGFP donor mice and transplanted into irradiated female recipient C57/BL6 mice. Chronic pancreatitis was induced with repeat injections of caerulein, while carcinogenesis was induced with an intrapancreatic injection of dimethylbenzanthracene (DMBA). Phenotype of engrafted donor-derived cells within the pancreas was assessed by immunohistochemistry, immunofluorescence and in situ hybridisation.

RESULTS

GFP positive cells were visible in the exocrine pancreatic epithelia from 3 months post transplantation. These exhibited acinar morphology and were positive for amylase and peanut agglutinin. Mice administered caerulein developed chronic pancreatitis while DMBA mice exhibited precursor lesions and pancreatic cancer. No acinar cells were identified to be donor-derived upon cessation of cerulein treatment, however rare occurrences of bone marrow-derived acinar cells were observed during pancreatic regeneration. Increased recruitment of BMDC was observed within the desmoplastic stroma, contributing to the activated pancreatic stellate cell (PaSC) population in both diseases. Expression of stellate cell markers CELSR3, PBX1 and GFAP was observed in BMD cancer-associated PaSCs, however cancer-associated, but not pancreatitis-associated BMD PaSCs, expressed the cancer PaSC specific marker CELSR3.

CONCLUSIONS

This study demonstrates that BMDC can incorporate into the pancreas and adopt the differentiated state of the exocrine compartment. BMDC that contribute to the activated PaSC population in chronic pancreatitis and pancreatic cancer have different phenotypes, and may play important roles in these diseases. Further, bone marrow transplantation may provide a useful model for the study of tumor-host interactions in cancer and pancreatitis.

Enhancing Cell therapies from the Outside In: Cell Surface Engineering Using Synthetic Nanomaterials

Therapeutic treatments based on the injection of living cells are in clinical use and preclinical development for diseases ranging from cancer to cardiovascular disease to diabetes. To enhance the function of therapeutic cells, a variety of chemical and materials science strategies are being developed that engineer the surface of therapeutic cells with new molecules, artificial receptors, and multifunctional nanomaterials, synthetically endowing donor cells with new properties and functions. These approaches offer a powerful complement to traditional genetic engineering strategies for enhancing the function of living cells.