Tepilamide Fumarate as a Novel Potentiator of Virus-Based Therapy.

Oncolytic virotherapy, using viruses such as vesicular stomatitis virus (VSVΔ51) and Herpes Simplex Virus-1 (HSV-1) to selectively attack cancer cells, faces challenges such as cellular resistance mediated by the interferon (IFN) response. Dimethyl fumarate (DMF) is used in the treatment of multiple sclerosis and psoriasis and is recognized for its anti-cancer properties and has been shown to enhance both VSVΔ51 and HSV-1 oncolytic activity. Tepilamide fumarate (TPF) is a DMF analog currently undergoing clinical trials for the treatment of moderate-to-severe plaque psoriasis. The aim of this study was to evaluate the potential of TPF in enhancing the effectiveness of oncolytic viruses. In vitro, TPF treatment rendered 786-0 carcinoma cells more susceptible to VSVΔ51 infection, leading to increased viral replication. It outperformed DMF in both increasing viral infection and increasing the killing of these resistant cancer cells and other cancer cell lines tested. Ex vivo studies demonstrated TPF's selective boosting of oncolytic virus infection in cancer cells without affecting healthy tissues. Effectiveness was notably high in pancreatic and ovarian tumor samples. Our study further indicates that TPF can downregulate the IFN pathway through a similar mechanism to DMF, making resistant cancer cells more vulnerable to viral infection. Furthermore, TPF's impact on gene therapy was assessed, revealing its ability to enhance the transduction efficiency of vectors such as lentivirus, adenovirus type 5, and adeno-associated virus type 2 across various cell lines. This data underscore TPF's potential role in not only oncolytic virotherapy but also in the broader application of gene therapy. Collectively, these findings position TPF as a promising agent in oncolytic virotherapy, warranting further exploration of its therapeutic potential.

Octyl itaconate enhances VSVΔ51 oncolytic virotherapy by multitarget inhibition of antiviral and inflammatory pathways.

The presence of heterogeneity in responses to oncolytic virotherapy poses a barrier to clinical effectiveness, as resistance to this treatment can occur through the inhibition of viral spread within the tumor, potentially leading to treatment failures. Here we show that 4-octyl itaconate (4-OI), a chemical derivative of the Krebs cycle-derived metabolite itaconate, enhances oncolytic virotherapy with VSVΔ51 in various models including human and murine resistant cancer cell lines, three-dimensional (3D) patient-derived colon tumoroids and organotypic brain tumor slices. Furthermore, 4-OI in combination with VSVΔ51 improves therapeutic outcomes in a resistant murine colon tumor model. Mechanistically, we find that 4-OI suppresses antiviral immunity in cancer cells through the modification of cysteine residues in MAVS and IKKß independently of the NRF2/KEAP1 axis. We propose that the combination of a metabolite-derived drug with an oncolytic virus agent can greatly improve anticancer therapeutic outcomes by direct interference with the type I IFN and NF-κB-mediated antiviral responses.

Optimal delivery of RNA interference by viral vectors for cancer therapy.

In recent years, there has been a surge in the innovative modification and application of the viral vector-based gene therapy field. Significant and consistent improvements in the engineering, delivery, and safety of viral vectors have set the stage for their application as RNA interference (RNAi) delivery tools. Viral vector-based delivery of RNAi has made remarkable breakthroughs in the treatment of several debilitating diseases and disorders (e.g., neurological diseases); however, their novelty has yet to be fully applied and utilized for the treatment of cancer. This review highlights the most promising and emerging viral vector delivery tools for RNAi therapeutics while discussing the variables limiting their success and suitability for cancer therapy. Specifically, we outline different integrating and non-integrating viral platforms used for gene delivery, currently employed RNAi targets for anti-cancer effect, and various strategies used to optimize the safety and efficacy of these RNAi therapeutics. Most importantly, we provide great insight into what challenges exist in their application as cancer therapeutics and how these challenges can be effectively navigated to advance the field.

Pevonedistat, a first-in-class NEDD8-activating enzyme inhibitor, sensitizes cancer cells to VSVΔ51 oncolytic virotherapy.

The clinical efficacy of VSVΔ51 oncolytic virotherapy has been limited by tumor resistance to viral infection, so strategies to transiently repress antiviral defenses are warranted. Pevonedistat is a first-in-class NEDD8-activating enzyme (NAE) inhibitor currently being tested in clinical trials for its antitumor potential. In this study, we demonstrate that pevonedistat sensitizes human and murine cancer cells to increase oncolytic VSVΔ51 infection, increase tumor cell death, and improve therapeutic outcomes in resistant syngeneic murine cancer models. Increased VSVΔ51 infectivity was also observed in clinical human tumor samples. We further identify the mechanism of this effect to operate via blockade of the type 1 interferon (IFN-1) response through neddylation-dependent interferon-stimulated growth factor 3 (ISGF3) repression and neddylation-independent inhibition of NF-κB nuclear translocation. Together, our results identify a role for neddylation in regulating the innate immune response and demonstrate that pevonedistat can improve the therapeutic outcomes of strategies using oncolytic virotherapy.

Safety and efficacy of autologous cell vaccines in solid tumors: a systematic review and meta-analysis of randomized control trials.

We conducted a systematic review and meta-analysis of randomized control trials to formally assess the safety and efficacy of autologous whole cell vaccines as immunotherapies for solid tumors. Our primary safety outcome was number, and grade of adverse events. Our primary efficacy outcome was clinical responses. Secondary outcomes included survival metrics and correlative immune assays. We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published between 1946 and August 2020 using any autologous whole cell product in the treatment of any solid tumor. The Cochrane Randomized Controlled Trial risk of bias tool was used to assess risk of bias. Eighteen manuscripts were identified with a total of 714 patients enrolled in control and 808 in vaccine arms. In 698 patients receiving at least one dose of vaccine, treatment was well tolerated with a total of 5 grade III or higher adverse events. Clinical response was reported in a minority (n = 2, 14%) of studies. Autologous cell vaccines were associated with improved overall (HR 1.28, 95% CI 1.01-1.63) and disease-free survival (HR 1.33, 95% CI 1.05-1.67) over thirteen and ten trials respectively. Where reported, immune assays correlated well with clinical outcomes. Our results suggest that autologous whole cell vaccination is safe and efficacious in increasing survival in patients undergoing treatment for solid tumors.Registration: PROSPERO CRD42019140187.

Unlocking the potential of dimethyl fumarate: enhancing oncolytic HSV-1 efficacy for wider cancer applications.

Immunotherapy and specifically oncolytic virotherapy has emerged as a promising option for cancer patients, with oncolytic herpes simplex virus-1 (oHSV-1) expressing granulocyte macrophage colony stimulating factor being the first OV to be approved by the FDA for treatment of melanoma. However, not all cancers are sensitive and responsive to oncolytic viruses (OVs). Our group has demonstrated that fumaric and maleic acid esters (FMAEs) are very effective in sensitizing cancer cells to OV infection. Of note, these FMAEs include dimethyl fumarate (DMF, also known as Tecfidera®), an approved treatment for multiple sclerosis and psoriasis. This study aimed to assess the efficacy of DMF in combination with oncolytic HSV-1 in preclinical cancer models. We demonstrate herewith that pre-treatment with DMF or other FMAEs leads to a significant increase in viral growth of oHSV-1 in several cancer cell lines, including melanoma, while decreasing cell viability. Additionally, DMF was able to enhance ex vivo oHSV-1 infection of mouse-derived tumor cores as well as human patient tumor samples but not normal tissue. We further reveal that the increased viral spread and oncolysis of the combination therapy occurs via inhibition of type I IFN production and response. Finally, we demonstrate that DMF in combination with oHSV-1 can improve therapeutic outcomes in aggressive syngeneic murine cancer models. In sum, this study demonstrates the synergistic potential of two approved therapies for clinical evaluation in cancer patients.

Dependency of EGFR activation in vanadium-based sensitization to oncolytic virotherapy.

Oncolytic virotherapy is a clinically validated approach to treat cancers such as melanoma; however, tumor resistance to virus makes its efficacy variable. Compounds such as sodium orthovanadate (vanadate) can overcome viral resistance and synergize with RNA-based oncolytic viruses. In this study, we explored the basis of vanadate mode of action and identified key cellular components in vanadate's oncolytic virus-enhancing mechanism using a high-throughput kinase inhibitor screen. We found that several kinase inhibitors affecting signaling downstream of the epidermal growth factor receptor (EGFR) pathway abrogated the oncolytic virus-enhancing effects of vanadate. EGFR pathway inhibitors such as gefitinib negated vanadate-associated changes in the phosphorylation and localization of STAT1/2 as well as NF-κB signaling. Moreover, gefitinib treatment could abrogate the viral sensitizing response of vanadium compounds in vivo. Together, we demonstrate that EGFR signaling plays an integral role in vanadium viral sensitization and that pharmacological EGFR blockade can counteract vanadium/oncolytic virus combination therapy.

Complex Germline K757N Mutation in Non-Small-Cell Lung Cancer: A Case Report.

Epidermal growth factor receptor (EGFR) mutations are usually oncogenic drivers of lung tumor development and progression. While common sensitizing mutations respond well to targeted therapy, the relevance of germline EGFR mutations is less clear. We describe a 65-year-old, previously healthy, male diagnosed with non-small-cell lung cancer. Familial history for lung cancer is negative. Targeted next-generation sequencing on the tumor biopsy sample revealed an atypical EGFR K757N mutation at 50% allele frequency and genetic review of a previously acquired gastric sample confirms the mutation as a germline change. He received standard first-line chemoimmunotherapy with carboplatin, pemetrexed, and pembrolizumab, and after 8 months therapy continues, with stable disease, to receive maintenance pemetrexed and pembrolizumab. To our knowledge, this is the first report of an atypical, germline K757N EGFR mutation. While the clinical relevance of this mutation is unclear, standard reporting of the allelic frequency of novel, atypical mutations can detect potential germline changes.

Safety and efficacy of autologous whole cell vaccines in hematologic malignancies: A systematic review and meta-analysis.

Autologous cell vaccines use a patient's tumor cells to stimulate a broad antitumor response in vivo. This approach shows promise for treating hematologic cancers in early phase clinical trials, but overall safety and efficacy remain poorly described. We conducted a systematic review assessing the use of autologous cell vaccination in treating hematologic cancers. Primary outcomes of interest were safety and clinical response, with secondary outcomes including survival, relapse rate, correlative immune assays and health-quality related metrics. We performed a search of MEDLINE, Embase and the Cochrane Register of Controlled Trials including any interventional trial employing an autologous, whole cell product in any hematologic malignancy. Risk of bias was assessed using a modified Institute of Health Economics tool. Across 20 single arm studies, only 341 of 592 enrolled participants received one or more vaccinations. Primary reasons for not receiving vaccination included rapid disease progression/death and manufacturing challenges. Overall, few high-grade adverse events were observed. One death was reported and attributed to a GM-CSF producing allogeneic cell line co-administered with the autologous vaccine. Of 58 evaluable patients, the complete response rate was 21.0% [95% CI, 10.4%-37.8%)] and overall response rate was 35.8% (95% CI, 24.4%-49.0%). Of 97 evaluable patients for survival, the 5-years overall survival rate was 64.9% (95% CI, 52.6%-77.2%) and disease-free survival was 59.7% (95% CI, 47.7%-71.7%). We conclude that, in hematologic malignancies, based on limited available data, autologous cell vaccines are safe and display a trend towards efficacy but that challenges exist in vaccine manufacture and administration.

Preoperative imaging of gastric GISTs underestimates pathologic tumor size: A retrospective, single institution analysis.

BACKGROUND: How well imaging size agrees with pathologic size of gastric gastrointestinal stromal tumors (GISTs) is unknown. GIST risk stratification is based on pathologic size, location, and mitotic rate. To inform decision making, the size discrepancy between imaging and pathology for gastric GISTs was investigated. METHODS: Imaging and pathology reports were reviewed for 113 patients. Bland-Altman analyses and intraclass correlation (ICC) assessed agreement of imaging and pathology. Changes in clinical risk category due to size discrepancy were identified. RESULTS: Computed tomography (CT) (n = 110) and endoscopic ultrasound (EUS) (n = 50) underestimated pathologic size for gastric GISTs by 0.42 cm, 95% confidence interval (CI): (0.11, 0.73), p = 0.008 and 0.54 cm, 95% CI: (0.25, 0.82), p < 0.001, respectively. ICCs were 0.94 and 0.88 for CT and EUS, respectively. For GISTs ≤ 3 cm, size underestimation was 0.24 cm for CT (n = 28), 95% CI: (0.01, 0.47), p = 0.039 and 0.56 cm for EUS (n = 26), 95% CI: (0.27, 0.84), p < 0.0001. ICCs were 0.72 and 0.55 for CT and EUS, respectively. Spearman's correlation was ≥0.84 for all groups. For GISTs ≤ 3 cm, 6/28 (21.4% p = 0.01) on CT and 7/26 (26.9% p = 0.005) on EUS upgraded risk category using pathologic size versus imaging size. No GISTs ≤ 3 cm downgraded risk categories. Size underestimation persisted for GISTs ≤ 2 cm on EUS (0.39 cm, 95% CI: [0.06, 0.72], p = 0.02, post hoc analysis). CONCLUSION: Imaging, particularly EUS, underestimates gastric GIST size. Caution should be exercised using imaging alone to risk-stratify gastric GISTs, and to decide between surveillance versus surgery.

The Diminishing Importance of Primary Site Identification in Cancer of Unknown Primary: A Canadian Single-Center Experience.

BACKGROUND: Cancer of unknown primary (CUP) describes patients with metastatic disease without an identified primary tumor site. Successful diagnosis and treatment of these patients remains difficult. Published guidelines on CUP have highlighted "favorable" subtype groups. We investigated a series of CUP patients to review adherence to guidelines, and identification of primary cancers or "favorable" subtypes. METHODS: Patients with histologically confirmed CUP at an academic institution from 2012 to 2018 were identified. Patient demographics, tumor presentation, diagnostic work-up and treatment information were retrospectively collected from electronic data records for descriptive analysis and compared to published clinical guidelines. The primary endpoint was the proportion of patients where the primary site was identified. Multivariable logistic regression models were used to identify factors associated with primary site identification. Kaplan-Meier survival curves were used to determine factors associated with poorer OS. RESULTS: Three hundred and five patients were included with a median follow-up time of 4.3 months. Primary tumor sites were identified in 109 patients (37.5%), which was most commonly lung cancer (33%). Statistical analyses did not identify any demographic or initial presentation factors associated with identifying the primary or not. More diagnostic tests did not increase the likelihood of primary site identification (P=0.44). Patients with an identified primary did not have longer OS than other patients (median 5.2 months vs. 4.7 months, P=0.47). 57 patients (18.7%) who had a defined "favorable" subtype experienced superior OS (36.6 months vs. 3.8 months; P<0.0001). Further, patients with good prognostic status who followed published treatment guidelines had longer OS (17.6 months vs. 13.2 months; P=0.04). CONCLUSIONS: CUP remains a difficult cancer to diagnose and treat. These results suggest identifying the primary has less impact than anticipated, but particular efforts to identify patients with "favorable" subtypes of CUP is important prognostically.

Perioperative blood transfusion is not an independent predictor for worse outcomes in retroperitoneal sarcoma surgery.

BACKGROUND: Surgery for retroperitoneal soft tissue sarcoma (RPS) is technically challenging, often requiring perioperative red blood cell transfusion (PBT). In other cancers, controversy exists regarding the association of PBT and oncologic outcomes. No study has assessed this association in primary RPS, or identified factors associated with PBT. METHODS: Data was collected on all resected primary RPS between 2006 and 2020 at The Ottawa Hospital (Canada) and University Hospital Birmingham (United Kingdom). 'PBT' denotes transfusion given one week before surgery until discharge. Multivariable regression (MVA) identified clinicopathologic factors associated with PBT and assessed PBT association with oncologic outcomes. Surgical complexity was measured using resected organ score (ROS) and patterns of resection. RESULTS: 192 patients were included with 98 (50.8%) receiving PBT. Median follow-up was 38.2 months. High tumour grade (OR 2.20, P = 0.048), preoperative anemia (OR 2.78, P = 0.020), blood loss >1000 mL (OR 4.89, P = 0.004) and ROS >2 (OR 2.29, P = 0.026) were associated with PBT on MVA. A direct linear relationship was observed between higher ROS and increasing units of PBT (ß = 0.586, P = 0.038). Increasingly complex patterns of resection were associated with increasing odds of PBT. PBT was associated with severe post-operative complications (P = 0.008) on MVA. Univariable association between PBT and 5-year disease-free or overall survival was lost upon MVA. CONCLUSIONS: Surgical complexity and high tumour grade are potentially related to PBT. Oncologic outcomes are not predicted by PBT but are better explained by tumour grade which subsequently may increase surgical complexity. Strategies to reduce PBT should be considered in primary RPS patients.

Author Correction: Dynamic fibroblast contractions attract remote macrophages in fibrillar collagen matrix.

The original version of this Article contained an error in the spelling of the author Christopher A. McCulloch, which was incorrectly given as Christopher McCulloch. This has now been corrected in both the PDF and HTML versions of the Article.

Dynamic fibroblast contractions attract remote macrophages in fibrillar collagen matrix.

Macrophage (Mϕ)-fibroblast interactions coordinate tissue repair after injury whereas miscommunications can result in pathological healing and fibrosis. We show that contracting fibroblasts generate deformation fields in fibrillar collagen matrix that provide far-reaching physical cues for Mϕ. Within collagen deformation fields created by fibroblasts or actuated microneedles, Mϕ migrate towards the force source from several hundreds of micrometers away. The presence of a dynamic force source in the matrix is critical to initiate and direct Mϕ migration. In contrast, collagen condensation and fiber alignment resulting from fibroblast remodelling activities or chemotactic signals are neither required nor sufficient to guide Mϕ migration. Binding of α2ß1 integrin and stretch-activated channels mediate Mϕ migration and mechanosensing in fibrillar collagen ECM. We propose that Mϕ mechanosense the velocity of local displacements of their substrate, allowing contractile fibroblasts to attract Mϕ over distances that exceed the range of chemotactic gradients.

ANG1 treatment reduces muscle pathology and prevents a decline in perfusion in DMD mice.

Vascular endothelial growth factor (VEGF) and other pro-angiogenic growth factors have been investigated to enhance muscle tissue perfusion and repair in Duchenne muscular dystrophy (DMD). Current understanding is limited by a lack of functional data following in vivo delivery of these growth factors. We previously used dynamic contrast-enhanced computed tomography to monitor disease progression in murine models of DMD, but no study to date has utilized this imaging technique to assess vascular therapy in a preclinical model of DMD. In the current study, we locally delivered VEGF and ANG1 alone or in combination to dystrophic hind limb skeletal muscle. Using functional imaging, we found the combination treatment as well as ANG1 alone prevented decline in muscle perfusion whereas VEGF alone had no effect compared to controls. These findings were validated histologically as demonstrated by increased alpha-smooth muscle actin-positive vessels in muscles that received either VEGF+ANG1 or ANG1 alone compared to the sham group. We further show that ANG1 alone slows progression of fibrosis compared to either sham or VEGF treatment. The findings from this study shed new light on the functional effects of vascular therapy and suggest that ANG1 alone may be a candidate therapy in the treatment of DMD.