Evaluation of Silicon Phthalocyanine 4 Photodynamic Therapy against Human Cervical Cancer Cells in Vitro and in Mice

Background: Cervical cancer is the second most common cancer in women worldwide [1]. Photodynamic therapy has been used for cervical intraepithelial neoplasia with good responses, but few studies have used newer phototherapeutics. We evaluated the effectiveness of photodynamic therapy using Pc 4 in vitro and in vivo against human cervical cancer cells. Methods: CaSki and ME-180 cancer cells were grown as monolayers and spheroids. Cell growth and cytotoxicity were measured using a methylthiazol tetrazolium assay. Pc 4 cellular uptake and intracellular distribution were determined. For in vitro Pc 4 photodynamic therapy, cells were irradiated at 667 nm at a fluence of 2.5 J/cm2 at 48 h. SCID mice were implanted with CaSki and ME-180 cells both subcutaneously and intracervically. Forty-eight hours after Pc 4 photodynamic therapy was administered at 75 and 150 J/cm2. Results: The IC50s for Pc 4 and Pc 4 photodynamic therapy for CaSki and ME-180 cells as monolayers were, 7.6 μM and 0.016 μM and >10 μM and 0.026 μM;as spheroids, IC50s of Pc 4 photodynamic therapy were, 0.26 μM and 0.01 μM. Pc 4 was taken up within cells and widely distributed in tumors and tissues. Intracervical photodynamic therapy resulted in tumor death, however mice died due to gastrointestinal toxicity. Photodynamic therapy resulted in subcutaneous tumor death and growth delay. Conclusions: Pc 4 photodynamic therapy caused death within cervical cancer cells and xenografts, supporting development of Pc 4 photodynamic therapy for treatment of cervical cancer. Support: P30-CA47904, CTSI BaCCoR Pilot Program.

Unsynchronized butyrophilin molecules dictate cancer cell evasion of Vγ9Vδ2 T-cell killing

Vγ9Vδ2 T cells are specialized effector cells that have gained prominence as immunotherapy agents due to their ability to target and kill cells with altered pyrophosphate metabolites.In our effort to understand how cancer cells evade the cell-killing activity of Vγ9Vδ2 T cells,we performed a comprehensive genome-scale CRISPR screening of cancer cells.We found that four molecules belonging to the butyrophilin(BTN)family,specifically BTN2A1,BTN3A1,BTN3A2,and BTN3A3,are critically important and play unique,nonoverlapping roles in facilitating the destruction of cancer cells by primary Vγ9Vδ2 T cells.The coordinated function of these BTN molecules was driven by synchronized gene expression,which was regulated by IFN-γsignaling and the RFX complex.Additionally,an enzyme called QPCTL was shown to play a key role in modifying the N-terminal glutamine of these BTN proteins and was found to be a crucial factor in Vγ9Vδ2 T cell killing of cancer cells.Through our research,we offer a detailed overview of the functional genomic mechanisms that underlie how cancer cells escape Vγ9Vδ2 T cells.Moreover,our findings shed light on the importance of the harmonized expression and function of gene family members in modulating T-cell activity.

Dissecting the multifactorial nature of demyelinating disease

Chondroitin sulfate proteoglycan-4（CSPG4） is a surface component of two key cell types（oligodendrocyte progenitor cells（OPCs） and myeloid cells） present in lysolecithin-induced lesions in mouse spinal cord.Two types of CSPG4 manipulations have been used to study the roles of these cells in myelin damage and repair：（1） OPC and myeloid-specific ablation of CSPG4,and（2） transplantation of enhanced green fluorescent protein（EGFP）-labeled progenitors to distinguish between bone marrow-derived macrophages and resident microglia.Ablation of CSPG4 in OPCs does not affect myelin damage,but decreases myelin repair,due to reduced proliferation of CSPG4-null OPCs that diminishes generation of mature oligodendrocytes for remyelination.Ablation of CSPG4 in myeloid cells greatly decreases recruitment of macrophages to spinal cord lesions,resulting in smaller initial lesions,but also in significantly diminished myelin repair.In the absence of macrophage recruitment,OPC proliferation is greatly impaired,again leading to decreased generation of myelinating oligodendrocytes.Macrophages may promote OPC proliferation via phagocytosis of myelin debris and/or secretion of factors that stimulate OPC mitosis.Microglia are not able to substitute for macrophages in promoting OPC proliferation.An additional feature of lesions in myeloid-specific CSPG4 null mice is the persistence of poorly-differentiated platelet-derived growth factor receptor α（PDGFRα） ＋ macrophages that may prolong damage.

Cancer Res:HDAC抑制剂可促进单抗药物对HER2阳性肿瘤的治疗效果

最近来自澳大利亚墨尔本的研究人员发现组蛋白去乙酰化酶抑制剂可以发动宿主免疫作为其抗肿瘤效应的一个基础。该研究为增强一些肿瘤免疫治疗药物的杀伤作用提供了新的方向。在这项发表在国际学术期刊Cancer Research上的研究中，研究人员发现组蛋白去乙酰化酶抑制剂panobinostat可以通过宿主免疫增强trastuzumab这种单抗治疗药物的抗肿瘤效果。

IFN-γ^(+) cytotoxic CD4^(+) T lymphocytes are involved in thepathogenesis of colitis induced by IL-23 and the foodcolorant Red 40

The food colorant Red 40 is an environmental risk factor for colitis development in mice with increased expression of interleukin(IL)-23.This immune response is mediated by CD4^(+)T cells,but mechanistic insights into how these CD4^(+)T cells trigger andperpetuate colitis have remained elusive.Here,using single-cell transcriptomic analysis,we found that several CD4^(+)T-cell subsetsare present in the intestines of colitic mice,including an interferon(IFN)-γ-producing subset.In vivo challenge of primed mice withRed 40 promoted rapid activation of CD4^(+)T cells and caused marked intestinal epithelial cell(IEC)apoptosis that was attenuated bydepletion of CD4^(+)cells and blockade of IFN-γ.Ex vivo experiments showed that intestinal CD4^(+)T cells from colitic mice directlypromoted apoptosis of IECs and intestinal enteroids.CD4^(+)T cell-mediated cytotoxicity was contact-dependent and required FasL,which promoted caspase-dependent cell death in target IECs.Genetic ablation of IFN-γconstrained IL-23-and Red 40-inducedcolitis development,and blockade of IFN-γinhibited epithelial cell death in vivo.These results advance the understanding of themechanisms regulating colitis development caused by IL-23 and food colorants and identify IFN-γ^(+)cytotoxic CD4^(+)T cells as a newpotential therapeutic target for colitis.

Inhibition of tumor autophagy:a strategy to improve antitumor immunity?

In a study recently published in Nature,Lawson et al.confirm several pathways previously implicated in tumor cell sensitivity to cytotoxic T lymphocytes(CTLs),and identify autophagy as an additional pathway involved in mediating tumor immune evasion.1 Autophagy is a regulated and conserved multistep process that enables cells to degrade and recycle intracellular components and is critical for cellular homeostasis.Autophagy has recently been associated with tumor immune evasion in pancreatic ductal adenocarcinoma,2 whereby this process selectively targeted the degradation of major histocompatibility complex I(MHC-I),limiting recognition,and anti-tumor responses by CTLs.Here,Lawson et al.identify an additional role for autophagy in tumor immune evasion,by mediating resistance to cytokine-mediated cell death.

Inhibition of tumor autophagy: a strategy to improve antitumorimmunity?

In a study recently published in Nature,Lawson et al.confirm several pathways previously implicated in tumor cell sensitivity to cytotoxic T lymphocytes(CTLs),and identify autophagy as an additional pathway involved in mediating tumor immune evasion.1 Autophagy is a regulated and conserved multistep process that enables cells to degrade and recycle intracellular components and is critical for cellular homeostasis.Autophagy has recently been associated with tumor immune evasion in pancreatic ductal adenocarcinoma,2 whereby this process selectively targeted the degradation of major histocompatibility complex I(MHC-I),limiting recognition,and anti-tumor responses by CTLs.Here,Lawson et al.identify an additional role for autophagy in tumor immune evasion,by mediating resistance to cytokine-mediated cell death.