Diverse Tumor Types Research Articles

Endothelial Protein C Receptor (EPCR), Protease Activated Receptor-1 (PAR-1) and Their Interplay in Cancer Growth and Metastatic Dissemination.

Endothelial protein C receptor (EPCR) and protease activated receptor 1 (PAR-1) by themselves play important role in cancer growth and dissemination. Moreover, interactions between the two receptors are essential for tumor progression. EPCR is a cell surface transmembrane glycoprotein localized predominantly on endothelial cells (ECs). It is a vital component of the activated protein C (APC)—mediated anticoagulant and cytoprotective signaling cascade. PAR-1, which belongs to a family of G protein–coupled cell surface receptors, is also widely distributed on endothelial and blood cells, where it plays a critical role in hemostasis. Both EPCR and PAR-1, generally considered coagulation-related receptors, are implicated in carcinogenesis and dissemination of diverse tumor types, and their expression correlates with clinical outcome of cancer patients. Existing data explain some mechanisms by which EPCR/PAR-1 affects cancer growth and metastasis; however, the exact molecular basis of cancer invasion associated with the signaling is still obscure. Here, we discuss the role of EPCR and PAR-1 reciprocal interactions in cancer progression as well as potential therapeutic options targeted specifically to interact with EPCR/PAR-1-induced signaling in cancer patients.

Isolation and Quantification of Metabolite Levels in Murine Tumor Interstitial Fluid by LC/MS.

Cancer is a disease characterized by altered metabolism, and there has been renewed interest in understanding the metabolism of tumors. Even though nutrient availability is a critical determinant of tumor metabolism, there has been little systematic study of the nutrients directly available to cancer cells in the tumor microenvironment. Previous work characterizing the metabolites present in the tumor interstitial fluid has been restricted to the measurement of a small number of nutrients such as glucose and lactate in a limited number of samples. Here we adapt a centrifugation-based method of tumor interstitial fluid isolation readily applicable to a number of sample types and a mass spectrometry-based method for the absolute quantitation of many metabolites in interstitial fluid samples. In this method, tumor interstitial fluid (TIF) is analyzed by liquid chromatography-mass spectrometry (LC/MS) using both isotope dilution and external standard calibration to derive absolute concentrations of targeted metabolites present in interstitial fluid. The use of isotope dilution allows for accurate absolute quantitation of metabolites, as other methods of quantitation are inadequate for determining nutrient concentrations in biological fluids due to matrix effects that alter the apparent concentration of metabolites depending on the composition of the fluid in which they are contained. This method therefore can be applied to measure the absolute concentrations of many metabolites in interstitial fluid from diverse tumor types, as well as most other biological fluids, allowing for characterization of nutrient levels in the microenvironment of solid tumors.

ATG12 Deficiency Leads to Tumor Cell Oncosis Owing to Diminished Mitochondrial Biogenesis and Reduced Cellular Bioenergetics

Liu et al. find a non-canonical role for an autophagy-related protein, ATG12, in regulating mitochondrial biogenesis and cellular bioenergetics. Cells deficient in ATG12 show distinct global metabolic features, decreasing β-oxidation (FAO), glycolysis, Krebs cycle (TCA cycle) activity, mitochondrial respiration and mitochondrial biogenesis as compared to control cells, leading in consequence to an insufficient energy supply and finally oncotic cell death, which does not occur in ATG12-deficient fibroblasts. ATG12, that we could detect partly at a mitochondrial localization, was upregulated in diverse types of solid tumors compared to the normal tissues in a multi-organ tissue microarray (TMA), thus suggesting a potential role for ATG12 in regulating cancer cell metabolism. Inducing oncosis by imposing an ATG12 deficiency in solid tumors might represent an anti-cancer therapy preferable to conventional caspase-dependent apoptosis that often shows undesirable consequences, such as incomplete cancer cell killing and silencing of the host immune system.

A 20-Year Experience With Resection of Primary Cardiac Tumors and Metastatic Tumors of the Heart

Cardiac tumors are uncommon, occurring in less than 1% of the population, and are comprised of numerous tumor types. Management of certain tumors types such as sarcoma have evolved and improved in the recent era. We evaluate the outcomes of patients who underwent resection of benign or malignant cardiac tumors with a focused review of cardiac sarcomas. Institutional data were reviewed from 1997 to 2017, and 180 patients who underwent tumor resection were identified. Outcomes and survival were examined based on tumor type. Two-thirds of patients (119 of 180) had benign tumors. Of 61 malignant tumors, 23 were sarcomas, 24were cavoatrial tumors, and 8 were T4 lung tumors. Inthe sarcoma group, operative mortality was 2 of 23 (9.1%). Neoadjuvant therapy was administered to 8 of 23patients (34.8%) with R0 resection achieved in 5 of 8 patients (62.5%). R0 resection was successful in 7 of 15 patients (46.7%) without neoadjuvant therapy. Mean survival with neoadjuvant therapy was 2.76 ± 3.85 years versus 1.28 ± 1.31 years without neoadjuvant therapy (p= 0.428). Mean survival with R0 resection was 2.79 ± 4.23 years compared with 1.64 ± 1.63 years without (p= 0.407). In the T4 lung tumor group, operative mortality was zero and R0 resection was achieved in 6 of 8 (75%). The cavoatrial tumors were mostly renal cell carcinoma resected with a mortality of 4.5%. Cardiac tumors are comprised of diverse tumor types. Indications for, and benefits of, resecting benign tumors and many malignant tumor types are clear, and operative outcomes are generally good. Cardiac sarcomas benefit from neoadjuvant therapy, which improves the rate of complete resection, thus improving survival.

Analysis of NTRK Alterations in Pan-Cancer Adult and Pediatric Malignancies: Implications for NTRK-Targeted Therapeutics.

Fusions that involve neurotrophic-tropomyosin receptor kinase (NTRK) genes are known drivers of oncogenesis. Therapies that target these ultra-rare, constitutionally active NTRK fusions have been remarkably effective. Herein, we analyze the prevalence of the full array of NTRK alterations-fusions, mutations, copy number alterations, and increased transcript expression-in diverse adult and pediatric tumor types to understand the landscape of NTRK aberrations in cancer. We assessed 13,467 samples available from The Cancer Genome Atlas (adult tumors) and the St Jude PeCan database (pediatric tumors) for the prevalence of NTRK fusions, as well as associated genomic and transcriptomic co-aberrations in different tumor types. NTRK fusions were observed in 0.31% of adult tumors and in 0.34% of pediatric tumors. The most common gene partners were NTRK3 (0.16% of adult tumors) followed by NTRK1 (0.14% of pediatric tumors). NTRK fusions were found more commonly in pediatric melanoma (11.1% of samples), pediatric glioma (3.97%), and adult thyroid cancers (2.34%). Additional genomic and transcriptomic NTRK alterations- mutation, amplification, and mRNA overexpression-occurred in 14.2% of samples, whereas the frequency of alterations that implicated NTRK ligands and the NTRK co-receptor (p75NTR) ranged from 3.8% to 5.4%. Among 31 adult samples carrying NTRK fusions, co-alterations occurred often and usually involved the downstream phosphoinositide-3-kinase signaling pathway, cell-cycle machinery, other tyrosine-kinase receptors, and mitogen-activated protein kinase signals. Whereas NTRK fusions are exceedingly rare, other NTRK abnormalities affect 14% of patients with cancer. Affecting these alterations has not yet been achievable in cancer. Genomic co-alterations occur frequently with NTRK fusions, but it is not known if co-targeting them can attenuate primary or secondary resistance to NTRK inhibitors.

MicroRNA-183-5p Inhibits Aggressiveness of Cervical Cancer Cells by Targeting Integrin Subunit Beta 1 (ITGB1).

BackgroundAccumulating studies demonstrate that microRNAs play crucial roles in multiple processes of cancer progression. Lower levels of miR-183 have ben observed in diverse types of tumors but the mechanism and precise function of miR-183-5p in cervical cancer have largely not been investigated.Material/MethodsThe level of miR-183-5p in different cervical cancer cell lines and clinical tissues was detected qRT-PCR assays. Transwell and wound-healing migration assays were conducted to assess the functional roles of miR-183-5p in over-expressing cervical cancer cells in vitro. Rescue assays were carried out to confirm the contribution of integrin subunit Beta 1 (ITGB1) to the aggressiveness of cancer cells regulated by miR-183-5p.ResultsmiR-183-5p was reduced in clinical tissues of cervical cancer and cell lines when compared to the normal subjects and normal cervical epithelial cell line, respectively. In addition, over-expression of miR-183-5p markedly inhibited migration and invasion in cervical cancer cells, and increased aggressiveness was observed in miR-183-5p inhibitor transfected cells. Furthermore, the luciferase reporter assays revealed that ITGB1 was the gene directly regulated by miR-183-5p. Notably, a negative association between the ITGB1 and miR-183-5p was found, and the gene expressions of ITGB1 was mediated by miR-183-5p in cervical cancer cells.ConclusionsmiR-183-5p serves as a latent anti-oncogene by targeting the metastasis-promoter gene, ITGB1.

FABP7 promotes cell proliferation and survival in colon cancer through MEK/ERK signaling pathway.

Colon cancer (CC), one of the most frequently diagnosed malignancies deriving from the digestive system, has greatly threatened human health and life. Fatty acid binding protein 7 (FABP7), an intracellular protein with the tissue-specific expression pattern, has been reported to be implicated in diverse types of human tumors. However, the biological role of FABP7 in CC is still poorly understood. The current study aimed to investigate the role of FABP7 in CC and illuminate the potential molecular mechanisms. In this present study, we found that FABP7 was highly expressed in CC tissues and cell lines, suggesting the possible involvement of FABP7 in CC tumorigenesis. Moreover, functional investigations showed that FABP7-overexpression promoted CC cell proliferation, colony formation, cell cycle progression and inhibited cell apoptosis; on the contrary, FABP7 knockdown produced an inhibitory effects on CC cell proliferation and survival. Notably, FABP7 knockdown inhibited colon tumor growth in vivo. In addition, mechanistic investigations demonstrated that FABP7 exerted its promoting effects on CC cell proliferation and survival through activation of the MEK/ERK signaling pathway. Collectively, our data indicate that FABP7 may be used as a novel diagnostic bio-marker and a potential therapeutic target for CC.

Methylation of Aurora kinase A by MMSET reduces p53 stability and regulates cell proliferation and apoptosis.

The histone methyltransferase multiple myeloma SET domain protein (MMSET/WHSC1) is highly expressed in diverse tumor types, and its expression appears to be involved in cell proliferation. In this study, we report that MMSET interacts with and methylates Aurora kinase A (AURKA). We show that MMSET-mediated methylation of AURKA induces interaction with p53 as well as enhanced kinase activity of AURKA, which results in the proteasomal degradation of p53. MMSET-mediated p53 degradation increases cell proliferation and results in oncogenic activity. Furthermore, knockdown of MMSET potently inhibits tumorigenic cells and renders them sensitive to growth inhibition by the therapeutic drug, alisertib (AURKA inhibitor). Taken together, our results suggest that MMSET is a regulator of p53 stability via methylation of AURKA in proliferating cells and might be a potential therapeutic target in solid tumors.

Abstract 2569: CAR19 T cells secreting antigen-retargeting fusion proteins have remarkable potency against diverse tumor types

Abstract Introduction. CAR-CD19 T cell therapeutics are approved to treat B cell leukemias and lymphomas. Previously we showed that providing CAR19 T cells with a retargeting fusion protein (FP), consisting of soluble CD19 protein linked to an scFv, redirects CAR19 T cell cytotoxic activity to other tumor antigens. Further, exposure of CAR19 T cells to normal or malignant B cells expressing CD19 improves effector function and phenotype, due to the provision of costimulatory signals. Such signals are missing when CAR-T cells engage antigens on solid tumor cells. In addition, lack of sufficient antigen for expansion and persistence is a critical issue for CAR T therapeutics targeting solid tumors in the clinical setting. We have redirected CAR19 T cells to other tumor antigens via novel FP and bispecific FP (biFP) expression cassettes. CAR19 T cells that express FP or biFP solve critical issues in the cell therapy field by 1) promoting CAR19 T cell expansion, efficacy and persistence by engaging CD19 on B cells; 2) addressing antigen heterogeneity/escape in hematologic malignancies and solid tumors. FP- and biFP-mediated cytotoxicity is extremely potent at pM concentrations. Here we provide examples of in vitro and in vivo modeling to characterize the activity of the CAR19 T cells that are retargeted to kill other tumor types. Experimental Procedures. A CAR-CD19 construct was created as the recipient for FP and biFP expression cassettes, in a lentiviral vector with an MCSV promoter. The CAR consists of the FMC63 scFv, a stalk, TM and CD28 and/or 4-1BB cytoplasmic signaling domains, and the CD3ε cytoplasmic signaling domain. FP and biFP cassettes were designed to encode the extracellular domain of the CD19 protein, followed by an scFv or VHH to one (FP) or two (biFP) antigens, separated from the CAR sequence by a P2A cleavage site. Results. Flow cytometry and binding analyses demonstrated FP and bi-FP-mediated bridging between target tumor cells and CAR19 T cells. In vitro cytotoxicity studies showed robust redirected killing of antigen+ (CD19-) tumor cells by CAR19 T cells. This cytotoxicity is specifically mediated by the secreted FP or biFP and correlated with antigen affinity. The efficiency of cytotoxicity was enhanced by the presence of CD19+ B cells. Tumor xenograft models using Her2+ and CD38+ tumor lines demonstrated effective tumor killing in vivo, with or without the presence of CD19+ cells. Conclusions. Redirected CAR19 T cells potently kill diverse tumor cells in vitro and in vivo. The strategy of redirecting CAR19 T cells to other tumor cell types by encoding novel FP and biFP expression cassettes solves critical issues in cell therapy by supporting CAR19 T cell activation and expansion and by providing a simple and modular multi-antigen targeting system. Further technology refinements include the creation of inducible promoters for FP expression, adding anti-PD-L1 activity, and providing cytokine support. Citation Format: Paul Rennert, Fay Dufort, Lihe Su, Lan Wu, Alyssa Birt, Roy Lobb, Christine Ambrose. CAR19 T cells secreting antigen-retargeting fusion proteins have remarkable potency against diverse tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2569.

Abstract 182: Superior targeting of tumor-stromal interactions and endothelial migration with a bispecific antibody to α5 and αv integrins

Abstract Introduction: The integrin α5β1 has been implicated in the adhesive and migratory response of prostate cancer cells induced by fibronectin fragments secreted by human bone-marrow derived mesenchymal stromal cells (hBM-MSCs) [Joshi, Cell Adh and Migr 2016). Genetic inactivation of integrin α5 in PC-3 cells downregulated the bcl-2 family of proteins and induced programmed cell death (Ren, Mol Cell Res 2017) - linking hBM-MSCs to a putative bone marrow niche survival program for prostate cancer cells. We hypothesized that the fibronectin-binding integrins α5β1 and integrin αv collaborate in broader tumor-stromal interactions and sought to examine the impact of combinatorial inactivation of these integrins. Methods: Monospecific antibodies to α5 (or its obligate α5β1 heterodimer) and to integrin alpha v (or the αvβ3 heterodimer) were utilized to assess the efficacy of a combinatorial neutralization approach over either single agent in α5/αv co-expressing cells from diverse tumor types including prostate, breast, glioma, cervix and uterine cancer. Assays included adhesion, migration, cell survival and the induction of endothelial migration in co-culture with stromal cells. To address the hypothesis that a bispecific integrin targeting antibody would be superior to a combinatorial approach with monospecific integrin antibodies, a bispecific antibody prototype that simultaneously targets the α5β1 and αv integrins [Bsα5β1/αvAb] was constructed and deployed in comparative assays. Results: Combined α5 and av neutralization with dual monospecific antibodies was superior to individual single agents in blocking adhesion, migration and the induction of endothelial chemotaxis across diverse tumor types that co-expressed α5 and αv integrins. However, a significant superiority of the Bsα5β1/αvAb was noted over the combinatorial approach with monospecific antibodies in these assays. In addition, a significant reduction in cell survival was noted in selected tumor types with the Bsα5β1/αvAb. Strikingly, the Bsα5β1/αvAb was significantly more potent than bevacizumab in the inhibition of endothelial migration induced by tumor-stromal cell interactions Conclusions: Combinatorial α5 and av integrin targeting in tumor cells that co-express α5 and av integrins effectively abrogates tumor-stromal interactions and the resultant endothelial migratory response. A Bsα5β1/αvAb demonstrates a significant improvement over combinatorial monospecific antibodies likely through diverse mechanisms including cross-priming. Targeting tumor, stromal and endothelial cells simultaneously with a Bsα5β1/αvAb approach represents a potentially effective therapeutic strategy for targeting diverse mechanisms of progressive disease in the tumor microenvironment. Citation Format: Raghav Joshi, Wenying Ren, Paul Mathew. Superior targeting of tumor-stromal interactions and endothelial migration with a bispecific antibody to α5 and αv integrins [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 182.

Abstract 1747: Hyaluronan (HA) accumulation restricts CD8+ T cell numbers and skews tumor-associated macrophage (TAM) phenotype in mouse syngeneic pancreatic tumors

Abstract The glycosaminoglycan hyaluronan (HA) is abundant in the tumor microenvironment (TME) of diverse solid tumor types, and tumor accumulation of HA is associated with poor patient outcome. We previously demonstrated, in multiple HA-rich mouse syngeneic tumor models, that enzymatic degradation of HA using PEGylated recombinant human hyaluronidase PH20 (pegvorhyaluronidase alfa; PEGPH20) enhanced tumor growth inhibition and increased tumor accumulation of T and NK cells when combined with a checkpoint inhibitor. However, the ability of HA accumulation in the TME to alter the composition of tumor-infiltrating immune cells has not been well characterized. Here, we addressed this question by performing a detailed immune phenotypic analysis of HA-poor and HA-rich tumors using a mouse syngeneic pancreatic tumor model. To achieve this, we transduced Pan02 cells with a lentivirus encoding hyaluronan synthase 3 (HAS3, Pan02-HAS3) or empty vector (EV, Pan02-EV). After peritibial implantation, Pan02-HAS3 tumors contained 13.4-fold higher levels of HA than Pan02-EV tumors, as determined by HA ELISA. Both variants grew with similar kinetics to the Pan02 parental line. Flow cytometric analysis of tumor-infiltrating immune cells in four independent and identical studies revealed an average 6.2-fold reduction in the number of CD8+ T cells in Pan02-HAS3 tumors compared with Pan02-EV. Likewise, numbers of CD4+ T cells and NK cells were reduced by an average of 4.8- and 2.9-fold, respectively, in Pan02-HAS3 tumors compared with Pan02-EV. In contrast, we did not observe consistent differences in the numbers of tumor-associated macrophages (TAMs), neutrophils/granulocytic myeloid-derived suppressor cells (G-MDSC), monocytes/monocytic (M)-MDSC, or dendritic cells (DCs) between the two tumor variants. However, within the TAM population, cells displaying an “M2-like” phenotype (CD206high MHCIIlow) were present at an average 10.5-fold higher frequency in Pan02-HAS3 tumors compared with Pan02-EV. Similarly, the percentage of DCs that were CD103+ CD11b- was reduced by 1.4-fold in Pan02-HAS3 tumors compared with Pan02-EV. Together, our data indicate that HAS3-driven HA accumulation in Pan02 mouse syngeneic tumors induces several aspects of immunosuppression: it restricts the numbers of tumor-infiltrating lymphocytes, and skews TAMs and DCs toward immunosuppressive phenotypes. These findings are consistent with our previous work, which demonstrated that combining PEGPH20 with anti-PD-L1 increased tumor-infiltrating lymphocyte numbers and reduced the frequency of CD206high MHCIIlow TAMs in Pan02-HAS3 tumors. Our results support the ongoing clinical evaluation of PEGPH20 in combination with immunotherapy in HA-rich tumor indications (NCT02563548 and NCT03193190). Citation Format: Benjamin Thompson, Trevor Kimbler, Jisook Lee, Chunmei Zhao, Kelly Chen, Renee Clift, Curtis B. Thompson, Sanna Rosengren, Daniel C. Maneval. Hyaluronan (HA) accumulation restricts CD8+ T cell numbers and skews tumor-associated macrophage (TAM) phenotype in mouse syngeneic pancreatic tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1747.

Abstract 4711: Modulation of NFκ-B signaling to optimize antitumor characteristics in macrophages

Abstract While it is known that nuclear factor κ-B (NF-κB) signaling within macrophages regulates expression of downstream targets that can mediate either pro- or antitumor functions, the mechanisms that define predominant characteristics are not well understood. As macrophages are present in the tumor microenvironment of diverse tumor types, their characteristics have the potential to either support or hinder tumor growth and metastatic spread. Therefore, a method to shift the balance of tumor associated macrophages from pro- to antitumor functions could potentially target tumor cells directly and also recruit and activate other immune cells, resulting in significant therapeutic benefit. Our studies are designed to gain an understanding of how to use modulation of NF-κB signaling as the “pinch point” to generate antitumor phenotypes and determine how to achieve this modulation in a patient. We are using immortalized bone marrow-derived macrophages or ex vivo tumor-associated macrophages in cell culture approaches and inducible transgenic mice in in vivo approaches to investigate the mechanisms by which NF-κB defines macrophage characteristics. Interactions with tumor cells are also being investigated using co-culture and murine models. Our data suggests that high levels of NFκ-B activity in macrophages induce both direct tumor cell killing and immune stimulating responses. We are testing two different translational approaches. The first is liposomal muramyl tripeptide ethanolamine that acts as an immune stimulant by increasing NF-κB activity in macrophages. The second is preferential delivery of siRNA against the inhibitor of NFκ-B (IκB-alpha) to tumor-associated macrophages using polymeric nanoparticles. We hope to better understand the mechanisms by which NFκ-B regulates macrophage functions to inform development of a novel macrophage-based immunotherapy that could be effective across a wide spectrum of solid tumors and metastatic disease. Citation Format: Esther Liu, Alyssa A. Hoover, Whitney R. Harris, Whitney Barham, Oleg Tikhomirov, Dineo Khabele, Zahra Mirafzahli, Todd D. Giorgio, Andrew J. Wilson, Fiona E. Yull. Modulation of NFκ-B signaling to optimize antitumor characteristics in macrophages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4711.

Characterization of KEAP1-NRF2 genomic alterations across diverse tumor types: Co-occurring alterations, survival outcomes, and implications for targeting cancer metabolism.

2558Background: CRISPR–Cas9-based genetic screening and metabolomic analyses have revealed that KEAP1-NRF2-mutated cancers depend on increased glutaminolysis and are vulnerable to glutaminase inhib...

Collagen IV-conveyed signals can regulate chemokine production and promote liver metastasis.

Liver metastases remain a major cause of death from gastrointestinal tract cancers as well as from other malignancies such as breast and lung carcinomas and melanoma. Understanding the underlying biology is essential for the design of effective targeted therapies. We previously reported that collagen IV α1/α2 overexpression in non-metastatic lung carcinoma (M27colIV) cells increased their metastatic ability, specifically to the liver and documented high collagen IV levels in surgical resections of liver metastases from diverse tumor types. Here, we aimed to elucidate the functional relevance of collagen IV to metastatic outgrowth in the liver. Gene expression profiling revealed in M27colIVcells significant increases in the expression of chemokines CCL5 (5.7-fold) and CCL7 (2.6-fold) relative to wild-type cells, and this was validated by qPCR and western blotting. Similarly, in human colon carcinoma KM12C and KM12SM cells with divergent liver-colonizing potentials, CCL7 and CCL5 production correlated with type IV collagen expression and the metastatic phenotype. CCL7 silencing by short hairpin RNA (shRNA) reduced experimental liver metastasis in both cell types, whereas CCL5 silencing reduced metastasis of M27colIV cells, implicating these cytokines in metastatic expansion in the liver. Subsequent functional analyses implicated both MEK/ERK and PI3K signaling upstream of CCL7 upregulation and identified CCL7 (but not CCL5) as a critical migration/invasion factor, acting via the chemokine receptor CCR3. Chemokine CCL5 was identified as a regulator of the T-cell immune response in the liver. Loss of CCL7 in KM12SM cells was also associated with altered E-cadherin and reduced vimentin and Snail expression, implicating it in epithelial-to-mesenchymal transition in these cells. Moreover, in clinical specimens of colon cancer liver metastases analyzed by immunohistochemistry, CCL5 and CCL7 levels paralleled those of collagen IV. The results identify the chemokines CCL5 and CCL7 as type IV collagen-regulated genes that promote liver metastasis by distinct and complementary mechanisms.

Tumor-agnostic therapy gets on TRK

Cancer In precision oncology, treatment is tailored to match the specific mutations that drive tumor growth. To date, this targeted approach has emphasized highly recurrent mutations specific to certain tumor types—for example, the BRAF mutations that occur in about 40% of melanomas. This paradigm of tumor type–specific therapy is changing, however, with the recognition that diverse tumor types can share the same low-frequency mutations. Recent clinical work illustrates the promise of “tumor-agnostic” targeted therapy. Drilon et al. studied 55 patients with 17 distinct tumor types that harbored rare chromosomal fusions involving tropomyosin receptor kinase (TRK) genes. They found that larotrectinib, a TRK inhibitor, produced durable responses in about 70% of the patients, regardless of their tumor's tissue of origin. New Engl. J. Med. 378 , 731 (2018).

Evaluating the efficacy of Tigecycline to target multiple cancer-types: A Review

Tigecycline (TIG) is a Food and Drug Administration (FDA)-approved antibiotic that has recently demonstrated its anti-cancer properties in diverse tumour types. This review will discuss current research findings and future directions pertaining to the use of TIG in mitigating acute myeloid leukemia (AML), non-small cell lung cancer (NSCLC), gastric cancer, hepatocellular carcinoma (HCC), breast cancer, melanoma, cervical squamous cell carcinoma (CSCC), and glioblastoma (GM). TIG exerts its therapeutic effects via inhibition of mitochondrial functionality, interference of various signal transduction pathways, and acting synergistically with pre-existing chemotherapy drugs, all of which contribute to cell death. In comparison to conventional treatments such as chemotherapy, TIG may result in less severe and reduced side effects; this may be attributed to its selectivity and non-invasiveness. Upon evaluation of TIG’s efficacy in targeting multiple cancer-types, future efforts should aim to validate findings through human trials, broadening the scope of cancers targeted, establishing novel TIG derivatives, and assessing its performance when used in combination with other treatments.

1,25-Dihydroxy vitamin D prevents tumorigenesis by inhibiting oxidative stress and inducing tumor cellular senescence in mice.

Human epidemiological studies suggest that 1,25(OH)2 D3 deficiency might increase cancer incidence, but no spontaneous tumors have been reported in mice lacking 1,25(OH)2 D3 or deficient in its receptor. In our study, we detected, for the first time, diverse types of spontaneous tumors in l,25(OH)2 D3 deficient mice more than 1 year of age. This was associated with increased oxidative stress, cellular senescence and senescence-associated secretory phenotype molecules, such as hepatocyte growth factor, mediated via its receptor c-Met. Furthermore, 1,25(OH)2 D3 prevented spontaneous tumor development. We also demonstrated that l,25(OH)2 D3 deficiency accelerates allograft tumor initiation and growth by increasing oxidative stress and DNA damage, activating oncogenes, inactivating tumor suppressor genes, stimulating malignant cell proliferation and inhibiting their senescence; in contrast, supplementation with exogenous l,25(OH)2 D3 or antioxidant, or knock-down of the Bmi1 or c-Met oncogene, largely rescued the phenotypes of allograft tumors. Results from our study suggest that 1,25(OH)2 D3 deficiency enhances tumorigenesis by increasing malignant cell oxidative stress and DNA damage, stimulating microenvironmental cell senescence and a senescence-associated secretory phenotype, and activating oncogenes and inactivating tumor suppressor genes, thus increasing malignant cell proliferation. Our study provides direct evidence supporting the role of vitamin D deficiency in increasing cancer incidence. Conversely, 1,25(OH)2 D3 prevented spontaneous tumor development, suggesting that this inhibitory effect prevents the initiation and progression of tumorigenesis, thus provides a mechanistic basis for 1,25(OH)2 D3 to prevent tumorigenesis in an aging organism.

Knockdown of EPCR inhibits the proliferation and migration of human gastric cancer cells via the ERK1/2 pathway in a PAR-1-dependent manner.

Endothelial proteinC receptor (EPCR) has been implicated in the carcinogenesis of diverse tumor types. This tumor-promoting effect of EPCR is associated with the upregulation of activated proteinC and the activation of protease-activated receptor1(PAR-1). However, the exact role of EPCR in gastric cancer(GC) and the mechanisms underlying the regulation of EPCR remain elusive. In the present study, we investigated the effects of EPCR on human GC cells, as well as the underlying mechanisms. An siRNA inference system was used to knock down the expression of EPCR in GC cells, and CCK-8, colony formation and Transwell assays were performed to determine the effects of EPCR knockdown on the proliferation and migration of the tumor cells. Additionally, cell cycle distribution and apoptosis were assessed by flow cytometry, and activated PAR-1 levels were determined by cell ELISA. The results indicated that the proliferation, clonogenicity and migration were significantly reduced and that the cell cycle was arrested in the Gap1phase by EPCR knockdown in SGC7901 and AGS cells. Meanwhile, apoptosis was promoted by EPCR knockdown in the two cell lines. The activation of PAR-1 on the cell surface of SGC7901 and AGS cells was significantly reduced after the knockdown of EPCR. By contrast, blockade of PAR-1 reduced the proliferation and migration of gastric cells in vitro. Additionally, after the knockdown of EPCR or treatment with PAR-1 antibody, the expression of pERK1/2 was significantly downregulated in the SGC7901 and AGS cells, while the expression levels of p-AKT(S473) and p-AKT(T308) were unchanged. The findings of the present study demonstrated that EPCR exerts pro-carcinogenic effects in GC cells in a PAR-1-dependent manner via the ERK1/2-MAPK pathway. Thus, EPCR may be a potential molecular diagnostic or therapeutic target for GC.

Improving immunotherapy for colorectal cancer using dendritic cells combined with anti-programmed death-ligand in vitro.

Monoclonal antibodies recognizing programmed death-ligand 1 (PD-L1) have been used for the clinical treatment of diverse tumor types as a form of immune checkpoint inhibitor, with a favorable therapeutic effect. Dendritic cells (DCs) are potent antigen-presenting cells that serve a pivotal role in the activation of T cells, particularly cytotoxic T lymphocytes (CTLs). DC vaccines loaded with tumor antigens, DC-CTLs and activated T cells have been revealed to be a safe and effective treatment approach against colorectal cancer within a clinical setting. In addition to tumor cells, PD-L1 is also highly expressed on DCs. As research examining the association between anti-PD-L1 and DCs is lacking, the present study compared the expression of PD-L1 on DCs in the peripheral blood of healthy donors and patients with colorectal cancer. Following the application of anti-PD-L1, the DC phenotypes, function of DC-mediated T cell induction and the cytotoxicity of CTLs were investigated by flow cytometry. The present study revealed that treatment with anti-PD-L1 may promote the maturation of DCs and enhance the functionality of the DC1 subtype. It may also increase the number of CTLs that are activated and produce CTL cells with more potent anti-tumor activity. Therefore, the creation of DC vaccines in conjunction with anti-PD-L1 may be an effective future treatment strategy for patients with colorectal cancer.

Population Genetics Approaches to Quantify Clonal Evolution

Cancer results from the acquisition of somatic alterations in an evolutionary process that typically occurs over many years, much of which is occult. Understanding the evolutionary dynamics that are operative at different stages of progression in individual tumors might inform the earlier detection, diagnosis, and treatment of cancer. For decades, tumor progression has been described as a gradual stepwise process, and it is through this lens that the underlying mechanisms have been interpreted and therapeutic strategies have been developed. Although these processes cannot be directly observed, the resultant spatiotemporal patterns of genetic variation amongst tumor cells encode their evolutionary histories. Cancer genome sequencing has thus yielded unprecedented insights into intra-tumor heterogeneity (ITH) and these data enable the inference of tumor dynamics using population genetics techniques. The application of such approaches suggests that tumor evolution is not necessarily gradual, but rather can be punctuated, resulting in revision of the de facto sequential clonal expansion model. For example, we previously described a Big Bang model of human colorectal tumor growth, wherein after transformation the neoplasm grows predominantly as a single terminal expansion in the absence of stringent selection, compatible with effectively neutral evolution1. In the Big Bang model, the timing of a mutation is the fundamental determinant of its frequency in the final tumor such that all major clones persist during growth and most detectable intra-tumor heterogeneity (ITH) occurs early. By analyzing multi-region and single gland genomic profiles in colorectal adenomas and carcinomas within a spatial agent-based tumor growth model and Bayesian statistical inference framework, we demonstrated the early origin of ITH and verified several other predictions of the Big Bang model. This new model provides a quantitative framework for understanding tumor progression with several clinical implications. In particular, rare but potentially aggressive subclones may be undetectable, providing a rich substrate for the emergence of resistance under treatment selective pressure. These data also suggest that some tumors may be born to be bad, wherein malignant potential is specified early. While not all tumors exhibit Big Bang dynamics, effectively neutral evolution has since been reported in other tumors and hence may be relatively common. These findings emphasize the need for methods to infer the role of selection in established human tumors and the systematic evaluation of distinct modes of evolution across tumor types and disease stages. To address this need, we developed an extensible population genetics framework to simulate spatial tumor growth and evaluate evidence for different evolutionary modes based on patterns of genetic variation derived from multi-region sequencing (MRS) data2. We demonstrate that while it is feasible to distinguish strong positive selection from neutral tumor evolution, weak selection and neutral evolution were indistinguishable in current data. Building on these findings, we developed a classifier that exploits novel measures of ITH and applied this to MRS data from diverse tumor types, revealing different evolutionary modes amongst treatment naïve tumors. To better understand evolutionary tempos during disease progression, we further characterized longitudinally sampled specimens. These findings have implications for forecasting tumor evolution and designing more effective treatment strategies.1. Sottoriva A, Kang H, Ma Z, et al. A Big Bang model of human colorectal tumor growth. Nature Genetics. 2015;47:209-16.2. Sun R, Hu Z, Sottoriva A, et al. Between-region genetic divergence reflects the mode and tempo of tumor evolution. Nature Genetics. 2017;49:1015-24. DisclosuresNo relevant conflicts of interest to declare.