Significant Difference In Tumor Volume Research Articles

The effects of glycemic index on prostate cancer progression in a xenograft mouse model

Abstract Background Previously, we found low-carbohydrate diets slowed prostate cancer (PC) growth and increased survival vs. a Western diet in mice, by inhibiting the insulin/IGF-1 axis. Thus, we tested whether modifying carbohydrate quality to lower glycemic index (GI) without changing quantity results in similar benefits as with reduced quantity. Methods Male SCID mice injected with LAPC-4 cells were single-housed and randomized when their tumors reached 200 mm3 on average to a LoGI (48% carbohydrate kcal, from Hylon-VII) or HiGI Western diet (48% carbohydrate kcal, from sucrose). Body weight and tumor volume were measured weekly. Body composition was assessed 35 days after randomization. Blood glucose and serum insulin, IGF-1 and IGFBP3 were measured at study end when tumor volumes reached 800 mm3. We analyzed gene expression of mice tumors by RNA-sequencing and human tumors using the Prostate Cancer Transcriptome Atlas. Results There were no significant differences in tumor volume (P > 0.05), tumor proliferation (P = 0.29), and overall survival (P = 0.15) between groups. At 35 days after randomization, the LoGI group had 30% lower body fat (P = 0.007) despite similar body weight (P = 0.58). At sacrifice, LoGI mice had smaller livers (P < 0.001) and lower glucose (P = 0.15), insulin (P = 0.11), IGF-1 (P = 0.07) and IGF-1:IGFBP3 ratio (P = 0.05), and higher IGFBP3 (P = 0.09) vs. HiGI, although none of these metabolic differences reached statistical significance. We observed differential gene expression and pathway enrichment in mice tumors by diet. The most upregulated and downregulated gene in the LoGI group showed expression patterns more closely resembling expression in human benign prostate tissue vs. PC. Conclusions In this single mouse xenograft model, consuming a low GI diet did not delay PC growth or survival vs. a high GI diet despite suggestions of decreased activation of the insulin/IGF-1 pathway. These data suggest that improving carbohydrate quality alone while consuming a high carbohydrate diet may not effectively slow PC growth.

Delivery of α-Particles By a Human-Rat Chimeric CD82 Monoclonal Antibody Potently Inhibits the Proliferation of CD82-Expressing Acute Myeloid Leukemia Cells in a Murine Xenograft Model

[Background] We previously found that acute myeloid leukemia (AML) cells aberrantly express CD82, a member of the tetraspanin family, on their surface. Functional analyses of CD82 by either depletion or forced expression of CD82 revealed that CD82 plays a role in the adhesion of AML cells to the bone marrow microenvironment in association with the inhibition of matrix metallopeptidase 9 (IJC 2013). In addition, CD82 transactivates several signaling pathways and upregulates anti-apoptotic Bcl-2L12 molecules in AML cells (Ikezoe T, et al. Int J Cancer. 2014;134:55, PLoS One. 2015;10: e0125017, Leukemia 2015;29:2296, Canc Sci. 2017;108:685). Alpha particle-emitting radionuclides are very attractive for cancer therapy, especially for micrometastases and isolated cancer cells commonly observed in leukemia, because of their high linear energy transfer and short effective path length in tissues. Astatine-211 ( 211At), with an appropriate half-life (7.2 hours), emits α-particles with higher energy in a shorter distance than ß-particles. It is ideal for cancer therapy through targeting tumor cells with α-particles by breaking double-stranded DNA while minimizing damage to normal cells. We have recently generated 211At-labeled human-rat chimeric CD82 monoclonal antibody ( 211At-h/r CD82 mAb) to deliver α-particles to CD82-expressing AML cells. [Aims] We conducted this study to evaluate the efficacy of a treatment strategy targeting CD82-expressing AML cells with 211At-h/r CD82 mAb. [Methods] Immunohistochemical staining was conducted to evaluate the binding of h/r CD82 mAb to U937 AML cells. 211At was produced by 209Bi(α, 2n) 211At nuclear reactions using an cyclotron (MP-30, Sumitomo Heavy Industries Ltd., Tokyo, Japan) at our institution, and h/r CD82 mAb was radiolabeled as described in our previous report (Oriuchi N, et al. Sci Rep. 2020;10:6810). A high-level CD82-expressing human AML cells xenograft (U937) was established in nude mice. In the biodistribution study, the mice were intravenously injected with 0.25 MBq of 211At-h/r CD82 mAb, and sacrificed at 1 min, 1, 3, 6, and 24 h after the injections (n=3 in each group). Blood, organs, and tumor tissues were collected, weighed, and measured for radioactivity using a gamma counter. The radioactivities of the blood, organs, and tumor tissues are presented as percent injected radioactivity dose per gram (%ID/g). In the treatment study, the mice were randomly divided into a nontreated (control, n=3) and two treated groups after the formation of palpable tumors. The mice in the treated groups were intravenously injected with either non-radiolabeled h/r CD82 mAb (h/r CD82 mAb, n=5) or 63.6 MBq of 211At-h/r CD82 mAb (n=4) on day 0. The tumor size of each mouse was measured daily until day 40 treatment. When the surface of the tumor tissue ruptured or the tumor diameter exceeded 20 mm, the tumor size measurement was stopped, and the mice were euthanized. [Results] Dense staining of CD82 by h/r CD82 mAb in a block of U937 cells was confirmed by immunohistochemical staining. The uptake levels of 211At-h/r CD82 mAb in the tumor significantly increased over time, which were 1.3 ± 0.3%ID/g, 6.3 ± 0.4%ID/g, 8.4 ± 2.0%ID/g, and 8.7 ± 0.8%ID/g at 1 min, and 1, 3, and 6 h after the injection, respectively. The highest tumor uptake level was achieved 6 h after the injection. This study revealed that the tumor volume significantly increased over time in the control and h/r CD82 mAb groups (from 106.9±36.6 mm 3 on day 0 to 4195 ± 1359.7 mm 3 on day16 in the control group, p<0.001; from 115.5 ± 11.7 on day 0 to 4045.5 ± 1912.1 mm 3 on day16 in the h/r CD82 mAb group, p<0.001). There was no significant difference in tumor volume between the control and h/r CD82 mAb groups. In contrast, the tumor volume significantly decreased over time after treatment with 211At-h/r CD82 mAb until day 10 (from 200.9±44.4 mm 3 on day 0 to 45.0 ± 60.5 mm 3 on day10, p<0.001 vs control and h/r CD82 mAb groups). Notably, two mice had no palpable tumor on day 45, indicating complete elimination of AML cells. [Conclusion] Delivery of α-particles by h/r CD82 mAb to CD82-expressing AML cells may be a promising strategy to overcome this lethal disease.

Macropinocytosis As a Means of Selectively Targeting RAS-Mutant Multiple Myeloma

Introduction Roughly, 50% of multiple myeloma (MM) is driven by mutant RAS, both at presentation and more at relapse. Currently, in MM there are no clinical approaches to target this disease subset and ongoing strategies to inhibit RAS function or downstream effectors have had limited clinical success in other tumors. This has prompted our team to look into other more indirect modes of RAS-selective targeting. Oncogenic RAS-driven cancers use a unique actin-driven endocytosis pathway, termed macropinocytosis (MP), to increase the nutrient supply and sustain proliferation. To create a strategy for targeting RAS mutant MM, we have investigated whether RAS-mutant MM cells undergo MP and whether this process can be exploited as a therapeutic vulnerability, by utilizing this pro-oncogenic biochemical mechanism to selectively deliver a toxin to the MM clone using a MP selective monobody-drug conjugate (MDC). Methods The MDC relies on a proprietary fibronectin-based scaffold (monobody) identified based on its physiochemical properties that facilitates MP selective internalization, and therefore targets RAS-mutant MM tumor cells, with a very favorable pharmacokinetic profile. MMAE was attached to the monobody with a cathepsin-cleavable linker and a maleimide group for conjugation to the C-terminal free cysteine on the monobody protein (MDC-MMAE). MDC-MMAE was pre-clinically evaluated both in-vitro and in-vivo, in human MM cell lines, patient cells and a doxycycline inducible mutant KRAS cell system. Results In-vitro cell line and patient cell studies demonstrated that RAS-mutant MM cells undergo MP whereas wild type (WT) cells do not. To understand the role of mutant RAS in driving uptake of the MDC, a doxycycline-inducible mutant KRAS V12 KMS11 system was established. The functionality of the inducibility of the cell system was verified using protein expression and membrane ruffling in the presence of doxycycline. Fluorescently-labeled monobody (MDC-Cy5.5) and TMR-Dextran underwent a high level of uptake in the presence of induced mutant RAS. In contrast, in conditions where MP was absent, no uptake of MDC-Cy5.5 and TMR-Dextran was seen. Furthermore, when KMS11 KRASV12 and WT KMS11 were treated with MDC-MMAE, a 2-fold increase in cell death was observed in the mutant RAS cell line compared to wild type RAS. In-vivo studies showed that the pharmacological properties of the drug when conjugated to the monobody enabled faster serum clearance compared to antibody drug conjugates (ADCs) and nanomaterials, while maintaining cellular impermeability allowing enhanced drug uptake via MP. Importantly, in-vivo the MDC-MMAE technology had an improved toxicity profile compared to ADC-MMAE, increasing tolerable drug delivery by upwards of 15-fold. To test the anti-tumor effects in-vivo, the L363 (NRAS Q61), WT KMS11, and KMS11 KRASV12 cell lines were subcutaneously injected into MM murine models. After tumors were established, 0.5mg/kg MDC-MMAE was administered every 7 days. Mutant RAS L363 and KMS11 KRASV12 tumors treated with MDC-MMAE exhibited roughly a 6-fold decrease in tumor size after 21 days while WT KMS11 tumors showed no significant difference in tumor volume. MDC-MMAE at 5mg/kg showed complete tumor regression as a single agent in L363 tumors. Improved outcomes were seen with MDC-MMAE in combination with standard of care options at lower doses. Additionally, MDC-MMAE has displayed enhanced immunogenic cell death that has not been seen with other chemotherapeutic options, making it an ideal partner for immunotherapy combination. Conclusion Limited clinical options exist for the treatment of mutant RAS MM tumors. We show that by taking advantage of MP, a process upregulated in RAS-mutant cancers, MDC-MMAE specifically targets and inhibits MM growth and improves survival in murine models. It can also be combined with other MM standard of care drugs and with immunotherapy drugs to have a potentially important clinical effect. In collaboration with Tezcat Biosciences, the MDC-MMAE technology has achieved a phase II SBIR for advancement to clinical application.

NCMP-17. IMPROVEMENT IN CRANIAL NEUROPATHIES FOLLOWING STEREOTACTIC RADIOTHERAPY ALONE FOR SKULL BASE MENINGIOMAS

Abstract Cranial neuropathies are a common presenting symptom in skull base meningiomas. Many of these tumors are not amenable to surgical resection; for these patients, stereotactic radiotherapy (SRT) is a viable option. Our study sought to investigate the efficacy of SRT for improving cranial neuropathies and identify predictors that portend favorable response. A single-institution retrospective analysis was performed for patients with skull base meningiomas causing cranial neuropathies who received SRT as sole treatment from 2001 to 2021. Clinical variables were collected and analyzed for predictors of improvement. Subgroup analysis for each type of cranial neuropathy was also performed. Overall 101 patients were included, of which 51 (50.4%) had an improvement in cranial neuropathy following SRT. There was no difference in gender or age between patients with and without improvement. The most common tumor location was cerebellopontine angle (n=38), followed by cavernous sinus (n=27) and optic canal (n=25). Cranial nerve II was most frequently affected (n=34), followed by VI (n=28) and V (n=27). There was no significant difference in tumor volume, radiation dose, location, or specific cranial nerve affected between patients with and without improvement. Median time to improvement was 8 months (IQR 3-15). In subgroup analysis, patients with optic neuropathy who experienced improvement after SRT were significantly younger (50.7 vs. 60.1 years, p=0.03), while patients with trigeminal neuropathy who experienced improvement were significantly older (69.6 vs. 58.7 years, p=0.03). For patients with extraocular movement neuropathies or vestibulocochlear dysfunction, there were no significant factors associated with improvement. Half of patients with cranial neuropathy from skull base meningiomas experience symptomatic improvement following sole SRT. Age may play a role in predicting improvement, with younger patients more likely to have improved vision and older patients more likely to experience improvement in trigeminal neuropathy.

MRI Assessment of Changes in Tumor Vascularization during Neoadjuvant Anti-Angiogenic Treatment in Locally Advanced Breast Cancer Patients.

Anti-VEGF (vascular endothelial growth factor) treatment improves response rates, but not progression-free or overall survival in advanced breast cancer. It has been suggested that subgroups of patients may benefit from this treatment; however, the effects of adding anti-VEGF treatment to a standard chemotherapy regimen in breast cancer patients are not well studied. Understanding the effects of the anti-vascular treatment on tumor vasculature may provide a selection of patients that can benefit. The aim of this study was to study the vascular effect of bevacizumab using clinical dynamic contrast-enhanced MRI (DCE-MRI). A total of 70 women were randomized to receive either chemotherapy alone or chemotherapy with bevacizumab for 25 weeks. DCE-MRI was performed at baseline and at 12 and 25 weeks, and in addition 25 of 70 patients agreed to participate in an early MRI after one week. Voxel-wise pharmacokinetic analysis was performed using semi-quantitative methods and the extended Tofts model. Vascular architecture was assessed by calculating the fractal dimension of the contrast-enhanced images. Changes during treatment were compared with baseline and between the treatment groups. There was no significant difference in tumor volume at any point; however, DCE-MRI parameters revealed differences in vascular function and vessel architecture. Adding bevacizumab to chemotherapy led to a pronounced reduction in vascular DCE-MRI parameters, indicating decreased vascularity. At 12 and 25 weeks, the difference between the treatment groups is severely reduced.

Whole-Lesion Apparent Diffusion Coefficient Histogram Analysis for Assessing Normal-Sized Lymph Node Metastasis in Cervical Cancer: Comparison Between Readout-Segmented and Single-Shot Echo-Planar Diffusion-Weighted Imaging.

To compare the value of whole-lesion apparent diffusion coefficient (ADC) histogram analysis derived from readout-segmented echo-planar imaging (RS-EPI) and single-shot echo-planar imaging (SS-EPI) diffusion-weighted imaging (DWI) in evaluating normal-sized lymph node metastasis (LNM) in cervical cancer. Seventy-six pathologically confirmed cervical cancer patients (stages IB and IIA) were enrolled, including 61 patients with non-LNM (group A) and 15 patients with normal-sized LNM (group B). The recorded tumor volume on T2-weighted imaging was the reference against which both DWIs were evaluated. Each ADC histogram parameter (including ADC max , ADC 90 , ADC median , ADC mean , ADC 10 , ADC min , ADC skewness , ADC kurtosis , and ADC entropy ) was compared between SS-EPI and RS-EPI and between the 2 groups. There was no significant difference in tumor volume between the 2 DWIs and T2-weighted imaging (both P > 0.05). Higher ADC max and ADC entropy but lower ADC 10 , ADC min and ADC skewness were found in SS-EPI than those in RS-EPI (all P < 0.05). For SS-EPI, lower ADC 90 and higher ADC kurtosis were found in group B than those in group A (both P < 0.05). For RS-EPI, lower ADC 90 and higher ADC kurtosis and ADC entropy were found in group B than those in group A (all P < 0.05). Readout-segmented echo-planar imaging ADC kurtosis showed the highest area under the curve of 0.792 in the differentiation of the 2 groups (sensitivity, 80%; specificity, 73.77%). Compared with SS-EPI, the ADC histogram parameters derived from RS-EPI were more accurate, and ADC kurtosis held great potential in differentiating normal-sized LNM in cervical cancer.

Abstract C035: ACKR1 expression in stromal cells regulates immune infiltration in triple negative breast cancer

Abstract Triple-negative breast cancer (TNBC), a highly aggressive and metastatic subtype of breast cancer, lacks expression of the estrogen and progesterone receptors and amplification of HER2 and comprises 15-20% of all breast cancer. Incidence and mortality of TNBC are higher in Black Americans than in other racial/ethnic groups. Conversely, Black patients are underrepresented in clinical breast cancer drug trials, limiting our understanding of differential treatment responses. Leukocyte infiltration is a key modulator of TNBC outcome, and Black patients show immunological differences that may contribute to differential outcomes in TNBC. About 60-80% of Black Americans are homozygous for a polymorphism in the Atypical Chemokine Receptor 1 (ACKR1) promoter region that causes loss of ACKR1 expression on red blood cells, also known as the “Duffy-null” serotype. ACKR1 is expressed on tumor cells, red blood cells, and endothelial cells, and can act as a chemokine sink or chemokine concentrator, depending on the context. Whole-tumor RNA analysis shows that overall loss of ACKR1 expression in TNBC tumors correlates strongly with decreased survival, but it is unclear which ACKR1-expressing cell type(s) contribute to this effect. Under inflammatory conditions, ACKR1 expression in endothelial cells localizes chemotactic cytokines at the endothelial junction, and loss of endothelial ACKR1 blocks the ability of leukocytes to extravasate through the endothelial barrier into surrounding tissues. We hypothesized that loss of endothelial/stromal ACKR1 reduces immune infiltration and activation in TNBC and racial/ethnic differences in ACKR1 expression may contribute to health disparities. To determine the role of ACKR1 in tumor immune infiltration, we chose a syngeneic immunocompetent mouse model to incorporate species-matched stromal-tumor interactions. We orthotopically inoculated E0771.LMB cells, a C57BL6/J syngeneic TNBC cell line, into ACKR1null and ACKR1het female mice. Tumor growth was measured triweekly, and tumor mass was measured at the 28-day endpoint. To measure immune infiltration, we fluorescently stained representative tumor cryosections with CD45 to detect all classes of infiltrating hematopoietic cells involved in immune response. There was no significant difference in tumor volume and mass among the ACKR1null and ACKR1het controls. Tumors implanted in ACKR1het controls showed broadly infiltrated leukocytes clusters, while tumors in ACKR1nullhosts showed sparse and infrequent leukocyte infiltration. Conclusion: Stromal ACKR1 does not have a strong effect on primary tumor growth. Loss of stromal ACKR1 reduces infiltration of leukocytes into the tumor microenvironment even when ACKR1 is not manipulated in the tumor cells, suggesting that ACKR1 in endothelial or other stromal cells regulates immune response in TNBC. Impact: Understanding the immunogenic functions of ACKR1 allelic variation will elucidate mechanisms of racially distinct therapeutic response in TNBC, enhance precision oncology, and promote cancer health equity. Citation Format: Chinwe Obianuju Ewenighi-Amankwah, Tanner Roach, Joseph Dufraine, Naiche Adler, Jan Kitajewski. ACKR1 expression in stromal cells regulates immune infiltration in triple negative breast cancer [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C035.

Role of synthetical amynoquinone ethyl 2-(1,4-dioxo-1,4-dihydronaphthalen-2-ylamino) acetate in inhibition of Ehrlich’s tumor

Quinones are naturally or synthetically occurring secondary metabolites that have various bio-dynamics, highlighting their antitumor potential. This has been explored through their selective cytotoxicity, and studies in medicinal chemistry about the relation between biological activity versus chemical structure may lead to the solution of the toxicity problems associated with quinones. In this context, the antitumor effect of a synthetic naphthoquinone, named Ethyl 2-(1,4-Dioxo-1,4-Dihydronaphthalen-2-Ylamino) Acetate, was tested using mice transplanted with Ehrlich ascitic tumor as an experimental model. The acute toxicity test was performed using 30 mice that received the aminoquinone at doses of 100, 200, 300, and 600mg/kg. After evaluation of the clinical findings in the spontaneous activity tests, the LD50 calculation for the test substance showed low levels of toxicity at doses lower than 244.11±23.29mg/kg. Thus, three experimental groups were established, where animals transplanted with tumor cells received NaCl vehicle solution (control, n=6), and the others were treated with 71.7mg/kg of Methotrexate (n=6) or 20mg/kg of Aminoquinone (n=6). All administrations were intraperitoneal, in a single dose. Three days after the implantation of the tumor cells the animals were weighed daily and evaluated for tumor biometry and development. The treatments occurred five days after the implantation of the tumor cells and were extended for 7 more days. At the end of the 12-day experimental period, all animals were euthanized for biochemical and histopathological analyses of the tumors and vital organs. The spontaneous activity test showed that the amount of responses associated with the nervous system tends to increase with the increase in dosage, highlighting the excitatory effect on the central nervous system in almost all dosages employed, followed by depressant activities on this system. There was a significant tumor reduction, both in animals treated with methotrexate (71.7 %) and in those treated with aminoquinone (91.6 %) in the control group. There was no significant difference in tumor volume between the animals treated with aminoquinone or methotrexate. The histopathological analysis revealed that in both treatments there were fewer mitoses in the tumor mass compared to the control group. However, there was apparent toxicity to the liver, heart, and left kidney in the treatment with methotrexate compared to aminoquinone. The significant capacity for tumor reduction presented by aminoquinone allows pointing it as a promising alternative for the development of a more efficient drug to control tumor development, being necessary for the development of new studies to deepen the knowledge about its mechanisms of action.

Probiotics enhances anti-tumor immune response induced by gemcitabine plus cisplatin chemotherapy for urothelial cancer.

Chemotherapy drugs, such as gemcitabine and cisplatin (GC), are frequently administered to patients with advanced urothelial carcinoma, however the influence of the gut microbiota on their action is unclear. Thus, we investigated the effects of GC on the gut microbiome and determined whether oral supplementation with a probiotics mixture of Lactobacillus casei Shirota and Bifidobacterium breve enhanced the anti-tumor immune response. After subcutaneous inoculation with MBT2 murine bladder cancer cells, syngenic C3H mice were randomly allocated into eight groups. The gut microbiome cluster pattern was altered in both the GC and oral probiotics groups (p=0.025). Both tumor-bearing conditions (no treatment) and GC chemotherapy influenced Pseudoclostridium, Robinsoniella, Merdimonas, and Phocea in the gut. Furthermore, comparison of the GC-treated and GC + probiotics groups revealed an association of four methyltransferase family enzymes and two short-change fatty acid-related enzymes with oral probiotics use. A significant difference in tumor volume was observed between the GC and GC + probiotics groups at week 2 of treatment. Additionally, decreased recruitment of cancer-associated fibroblasts and regulatory T cells, and activation of CD8+ T cells and dendritic cells were observed in the tumor microenvironment. Our findings reveal the positive effects of a probiotics mixture of Lactobacillus and Bifidobacterium in enhancing anti-tumor effects through the gut-tumor immune response axis. Future clinical trials are needed to evaluate the full benefits of this novel supplement with oral probiotics in patients with advanced urothelial carcinoma.

Accelerated 3D high-resolution T2-weighted breast MRI with deep learning constrained compressed sensing, comparison with conventional T2-weighted sequence on 3.0 T

PurposeTo evaluate the feasibility of isotropic 3D high-resolution T2-weighted imaging (T2WI) MRI sequences and compare the images reconstructed by integrating artificial intelligence-compressed sensing (AI-CS), compressed sensing (CS), and conventional 2D T2WI sequences for quality. Materials and methodsFifty-two female patients (ages: 26–80 years) with suspected breast cancer were enrolled. They underwent breast MRI examinations using three sequences: conventional T2WI, CS 3D T2WI, and AI-CS 3D T2WI. Image quality, signal-to-noise ratio (SNR), contrast-to-noise ratio, tumor volume, and maximal tumor diameter were compared using the Friedman test. Image quality was scored on a 5-point scale, with 1 indicating nonassessable quality and 5 indicating excellent quality. Tumor volume and maximal tumor diameter were compared based on AI-CS 3D T2WI (slightly high signal), conventional T2WI, and dynamic contrast-enhanced (DCE) sequences. ResultsAll three T2WI were successfully performed in all patients. 3D CS and AI-CS were significantly better than conventional T2WI in terms of lesion conspicuity and morphology, structural details, overall image quality, diagnostic information for breast lesions, and breast tissue delineation (P < 0.001). The SNR of conventional T2WI was significantly higher for 3D T2WI sequences. The contrast-to-noise ratio was significantly higher for AI-CS 3D T2WI than for conventional T2WI sequence. There was no significant difference in tumor volume between DCE (8.08 ± 16.51) and AI-CS 3D T2WI (8.25 ± 16.29) sequences and no significant differences in tumor diameter among DCE, AI-CS 3D T2WI, and conventional T2WI sequences. ConclusionIsotropic-resolution 3D T2WI sequences can be acquired using AI-CS while maintaining image quality and diagnostic value, which may pave the way for isotropic 3D high-resolution T2WI for clinical application.

Preoperative Evaluation of 3D-MRI on the Depth of Myometrial Invasion of Endometrial Carcinoma: 3D Study of Endometrial Carcinoma

Background: To evaluate the preoperative diagnostic efficacy of 3D-MRI for the depth of myometrial invasion of endometrial carcinoma. Methods: A total of 116 patients with endometrial carcinoma who had undergone pelvic MRI before surgery were included. Mimics 21.0 (Materialize Co., Belgium) software was used to reconstruct three-dimensional MRI models (3D-MRI). The tumor volume and surface area, uterine volume and surface area were measured, and the tumor volume ratio was calculated. TVR (Tumor Volume Ratio) = tumor volume/uterine volume, TAR (Tumor Area Ratio) = tumor surface area/uterine surface area. Postoperative pathology was used as the gold standard to compare the accuracy, sensitivity, specificity, negative predictive value, and positive predictive value of conventional MRI and 3D-MRI in preoperative assessment of endometrial carcinoma myometrial invasion. Results: The accuracy and specificity of 3D-MRI in the diagnosis of deep myometrial invasion were better than conventional MRI (p &lt; 0.05). There was no statistically significant difference in tumor volume or surface area between stage IA and stage IB (p &gt; 0.05), while TVR and TAR showed significant statistical differences (8.05 ± 0.66 vs. 19.12 ± 3.20, p &lt; 0.01; 21.38 ± 1.04 vs. 35.15 ± 3.42, p &lt; 0.01). Further analysis, the area under the ROC curve of TVR is 0.738, p &lt; 0.01, and the best cut-off value is 13.59%; the area under the ROC curve of TAR is 0.770, p &lt; 0.01, and the best cut-off value is 27.41%. Conclusions: Preoperative 3D-MRI can effectively assess the myometrial invasion of endometrial carcinoma.

Abstract 719: Preclinical testing of CD73 inhibitors for pancreatic cancer immunoprevention

Abstract Introduction: Pancreatic ductal adenocarcinoma (PDAC) is characterized by a profoundly immunosuppressive microenvironment. Innovative therapeutic strategies are urgently needed to stop the progression of precancerous lesions into aggressive PDAC, which remains a lethal malignancy. The goal of this research project is to test the immunopreventive strategies by targeting the ectonucleotidase CD73, one of the gatekeeper enzymes responsible for adenosine production and the formation of immunosuppressive tumor microenvironment in this malignancy. We hypothesize that inhibition of CD73 will prevent pancreatic intraepithelial neoplasia (PanIN) formation and progression to PDAC by reversing immunosuppression. Materials and methods: A syngeneic PDAC mouse model was employed by injecting 100k murine pancreatic cancer (KPC) cells in flanks of C57BL/6 female mice. Oral gavage of AB680 (small molecule CD73 inhibitor) was given three days/week at 10mg/kg starting the day after KPC injections and tumor sizes were measured weekly. Toxicity was analyzed by serum ALT analysis. At the time of death 6 weeks post-KPC inoculation, tumor volume and mass were recorded. In another experiment, AB680 was administered 3 days/week at 10mg/kg for 5 weeks. CyTOF immunoprofiling of digested tumors from control and AB680 treated mice and HPLC analysis on serum from the time of death were performed. Results: In experiment 1, by week three of the study, there was a significant difference in tumor volume between the control and AB680 treated groups (P=0.02). However, in weeks 4-5 AB680 reduced tumor growth compared to vehicle controls, but the grouped statistical analysis was not significant. When observing individual tumors, there was a reduction in tumor size in 30% of the AB680 treated mice between weeks 3-5, but the difference was not statistically different. ALT analysis determined AB680 does not induce liver toxicity. For experiment 2 (3x/week treatment with AB680), there was a significant reduction in tumor growth. Activated CD8-positive T cells, dendritic cells, and macrophages were significantly increased in the syngeneic tumors from AB680 treated mice. The intratumoral adenosine levels were significantly decreased in AB680 treated mice compared to vehicle treated mice. Conclusion: We conclude oral gavage delivery of CD73 inhibitor AB680 at 10mg/kg (6x/week) reduces tumor growth in KPC syngeneic tumor bearing mice. Treatment with AB680 at 10mg/kg 3x/week significantly increases tumor doubling time, significantly alters intratumoral immune cell populations, and results in a significant decrease in intratumoral adenosine levels. In addition, we observed a significant increase in infiltration of activated CD8-positive T cells indicating oral gavage delivery using AB680 reverses immunosuppression in vivo. [Supported by NCI 75N91019D00021/75N91020F00002] Citation Format: Kanchan Singh, Vidhi Chandra, Lincoln Ballew, Tingting Mills, Erika Y. Faraoni, Trent Clark, Lana A. Vornik, Michelle I. Savage, Holger K. Eltzschig, Altaf Mohammed, Shizuko Sei, Powel H. Brown, Florencia McAllister, Jennifer Bailey-Lundberg. Preclinical testing of CD73 inhibitors for pancreatic cancer immunoprevention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 719.

Radical prostatectomy findings and oncologic outcomes in patients with prostate cancer detected on systematic sextant biopsy only, MRI-targeted biopsy only, or both.

Magnetic resonance imaging-targeted biopsy (T-Bx) has been shown to more accurately detect clinically significant prostate cancer. However, the clinical significance of cancer detection on T-Bx, followed by definitive treatment, needs to be further investigated. We herein investigated unique cohorts of patients with prostate cancer detected on systematic sextant biopsy (S-Bx) and/or T-Bx. We assessed consecutive patients who had undergone T-Bx with concurrent S-Bx (6 sites, ≥12 cores), followed by radical prostatectomy from 2015 to 2019. Within our Surgical Pathology database, we identified a total of 222 men who met the inclusion criteria for prostatic adenocarcinoma on either S-Bx or T-Bx, or both (B-Bx). Radical prostatectomy findings and oncologic outcomes were then compared among groups. Prostate cancer was detected on S-Bx only (n = 32; 14%), T-Bx only (n = 40; 18%), or B-Bx (n = 150; 68%). Compared to cases with cancer detected on S-Bx only, those on T-Bx only or B-Bx showed significantly higher tumor grade (highest Grade Group in each patient) on biopsy and significantly larger estimated tumor volume on prostatectomy. There were no significant differences in tumor volume on biopsy, tumor grade on prostatectomy (except S-Bx vs. B-Bx), pT or pN stage category, surgical margin status, or preoperative prostate-specific antigen level between cases where cancer was detected on S-Bx only vs. T-Bx only or B-Bx. There were also no significant differences in any of these clinicopathologic features between cancers detected on T-Bx only vs. B-Bx. Kaplan-Meier analysis revealed a significantly higher risk of biochemical recurrence after prostatectomy in patients whose cancer was detected on T-Bx only (P = 0.020) or B-Bx (P = 0.032) than in those on S-Bx only. No significant difference in recurrence-free survival between T-Bx only vs. B-Bx cases (P = 0.601) was seen. In multivariate analysis, cancer detection on T-Bx only (vs. S-Bx only) showed significance for recurrence (hazard ratio = 8.482, P = 0.045). Detection of prostate cancer on T-Bx, in addition to or instead of S-Bx, was found to be associated with larger tumor volume as well as worse prognosis. However, no significant clinicopathologic impact of simultaneous tumor detection on S-Bx was indicated in patients with prostate cancer present on T-Bx.

A Systematic Review of Cervical Ganglioneuromas

ObjectiveTo perform a systematic review of the literature evaluating clinical characteristics and management of cervical ganglioneuromas (CGNs).Data SourcesPubMed, Embase, and Cochrane Library databases were searched. Data such as patient demographics, imaging, and treatments were obtained.Review MethodsPertinent studies were downloaded, and the full text was reviewed by 4 authors (N.P., S.S., C.F., D.T.). Results were reported via the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta‐analyses).ResultsFifty‐two studies with 58 patients were identified in the literature. Of the 58 patients, 22 were adults and 36 were pediatric. The most common reported location of CGN was within the parapharyngeal space (76%), followed by the retropharyngeal (19%) and paravertebral/prevertebral (7%) spaces. The most common presenting symptoms included a nontender mass (29.3%), dysphagia (17.2%), and hoarseness (10.3%). Interestingly, the average tumor volume for patients with postoperative Horner’s syndrome was 183 mm3 (n = 21, 47.7%) vs 946 mm3 in patients without Horner’s syndrome (n = 23, 52.3%). This represents a statistically significant finding (P =. 018). There exists no significant difference in tumor volumes between adult and pediatric patients with Horner’s syndrome (P =. 645).ConclusionCGN is a rare tumor of the sympathetic nervous system. Management should involve complete surgical excision with biopsy. We found that patients with small‐volume CGNs are significantly more likely to experience postoperative Horner’s syndrome. This finding is independent of age and should therefore be taken into consideration in any patient with suspected CGN.

Predictors of Recurrence After Sub-total or Near-total Resection of Vestibular Schwannoma: Importance of Tumor Volume and Ventral Extension.

To evaluate the predictors of remnant tumor regrowth and need for salvage therapy after less than gross total resection (GTR) of vestibular schwannoma (VS). Retrospective chart review. Tertiary neurotologic referral center. Patients who underwent VS resection between 2008 and 2019 either with GTR, near total resection (NTR), and subtotal resection (STR). Microsurgical resection, salvage radiosurgery. Regrowth free interval, salvage free interval, tumor doubling rate. Three hundred eighty five cases (GTR = 236, NTR = 77, and STR = 71) from 2008 to 2019 were included. STR cohort had much larger and complex tumors with significant differences in tumor volume, ventral extension and brainstem compression (p < 0.001). On single predictor analysis, tumor volume, ventral extension, brainstem compression as well as STR strategy was associated with significant increased risk of regrowth and need for salvage therapy. Multivariate analysis revealed STR strategy as significant predictor of regrowth (hazard ratio 3.79, p < 0.0005). Absolute remnant volume and extent of resection (EOR) did not predict regrowth. A small proportion of cases (NTR = 4%, STR = 15%) eventually needed salvage radiosurgery with excellent ultimate local tumor control with no known recurrence to date. Conservative surgical strategy employing NTR or STR can be employed safely in large and complex VS. While there is increased risk of regrowth in the STR cohort, excellent local control can be achieved with appropriate use of salvage radiosurgery. No disceret radiologic or operative predictors of regrowth were identified.

Treatment Effect of a Vascular-Disrupting Agent Dynamically Monitored by DWI: An Animal Experimental Study.

Objective To investigate the treatment effect of a vascular-disrupting agent, M410, using diffusion-weighted imaging in a rabbit model of hepatic VX2 tumor. Methods 28 New Zealand white rabbit models with VX2 liver tumors were established and were randomly divided into M410 (intravenous injection of M410 at a dose of 25 mg/kg every three days) and control (intravenous injection of saline every three days) groups. Conventional and diffusion-weighted imaging (DWI) were acquired on a 3.0 T MR unit at baseline, 4 h, d 1, d 4, d 7, and d 14 posttreatment. B-value with 700 (s/mm2) was chosen during DWI examinations. Tumor volume and apparent diffusion coefficient (ADC) values of the entire tumor and solid component of the tumor at every time point were measured. Two randomly chosen rabbits from each group were sacrificed for H&E staining and CD34 immunohistochemical assessments at each time point. An independent sample t-test was used to assess differences in tumor sizes and ADC values of the entire tumor and solid component of tumors between two groups, with P < 0.05 considered statistically significant. Result There was no significant difference in tumor volume between the two groups at baseline, 4 h, and d 1. With time, the tumors in the control group grew significantly faster than those in the M410 group, and the average ADC values of the M410 group were lower than those of the control group at d 1 and higher than those of the control group at d 4; as such, there were statistical differences between the two groups at these two time points but not at the other four time points. The following pathological results reflected the underlying morphological changes and vascular alterations. Conclusions M410 performed well in inhibiting the growth of the hepatic VX2 tumor which could be noninvasively monitored by DWI metrics.

A Conjugation Strategy to Modulate Antigen Binding and FcRn Interaction Leads to Improved Tumor Targeting and Radioimmunotherapy Efficacy with an Antibody Targeting Prostate-Specific Antigen.

Simple SummaryThe present study demonstrates that a radiolabeling strategy can positively modify hu5A10′s capacity to bind PSA and complex with the FcRn receptor, which results in a more homogenous activity distribution in tumors and enhanced therapy efficacy. These new innovative radiochemistry ideas could potentially decrease relapse of tumors in patients treated with internalizing antibodies.Background: The humanized monoclonal antibody (mAb) hu5A10 specifically targets and internalizes prostate cancer cells by binding to prostate specific antigen (PSA). Preclinical evaluations have shown that hu5A10 is an excellent vehicle for prostate cancer (PCa) radiotheranostics. We studied the impact of different chelates and conjugation ratios on hu5A10′s target affinity, neonatal fc-receptor interaction on in vivo targeting efficacy, and possible enhanced therapeutic efficacy. Methods: In our experiment, humanized 5A10 (hu5A10) was conjugated with DOTA or DTPA at a molar ratio of 3:1, 6:1, and 12:1. Surface plasmon resonance (SPR) was used to study antigen and FcRn binding to the antibody conjugates. [111In]hu5A10 radio-immunoconjugates were administered intravenously into BALB/c mice carrying subcutaneous LNCaP xenografts. Serial Single-photon emission computed tomography (SPECT) images were obtained during the first week. Tumors were harvested and radionuclide distribution was analyzed by autoradiography along with microanatomy and immunohistochemistry. Results: As seen by SPR, the binding to PSA was clearly affected by the chelate-to-antibody ratio. Similarly, FcRn (neonatal fc-receptor) interacted less with antibodies conjugated at high ratios of chelator, which was more pronounced for DOTA conjugates. The autoradiography data indicated a higher distribution of radioactivity to the rim of the tumor for lower ratios and a more homogenous distribution at higher ratios. Mice injected with ratio 3:1 111In-DOTA-hu5A10 showed no significant difference in tumor volume when compared to mice given vehicle over a time period of 3 weeks. Mice given a similar injection of ratio 6:1 111In-DOTA-hu5A10 or 6:1 111In-DTPA-hu5A10 or 12:1 111In-DTPA-hu5A10 showed significant tumor growth retardation. Conclusions: The present study demonstrated that the radiolabeling strategy could positively modify the hu5A10′s capacity to bind PSA and complex with the FcRn-receptor, which resulted in more homogenous activity distribution in tumors and enhanced therapy efficacy.

Abstract 3198: Hyperactive c-Met and ErbB signaling detected in a sub-group of ovarian patient tumors: Patient sub-group may benefit from c-Met and pan-HER combination therapy

Abstract Background: Sub-groups of breast, lung, and colon cancer patients with genetic variants associated with dysregulated ErbB signaling benefit from treatment with ErbB targeted therapies. No sub-groups of ovarian cancer patients with actionable ErbB genetic variants have yet been found. Measurement of biological factors other than genetic variants, such as ErbB signaling activity, may identify ovarian cancer patients likely to benefit from ErbB targeted therapies. We have previously reported studies detecting dysregulated ErbB and c-Met signaling activity in 20%-25% of HER2-negative breast cancer patient tumors using the CELx Multi-Pathway (MP) Signaling Function Test. To determine whether ErbB or c-Met signaling dysregulation is involved in ovarian cancer, the CELx MP test was adapted to analyze ovarian tumor cells. The current study set out to: 1) characterize c-Met and ErbB family signaling activity in ovarian patient tumor cells and ovarian tumor cell lines; 2) evaluate in vivo response to pan-HER and c-Met inhibitors in an ovarian tumor xenograft model. Methods: For the ex vivo studies, a set of fresh tumor specimens from 15 ovarian cancer patients (90% high-grade serous, 10% endometrioid) and a set of 12 ovarian cancer cell lines was obtained. Cell samples were cultured from each patient specimen. Real-time live cell response to specific ErbB and c-Met agonists (NRG1b, EGF, or HGF) with or without an antagonist (2C4, a HER2 dimerization inhibitor or tepotinib, a c-Met kinase inhibitor) was measured and quantified using an xCELLigence impedance biosensor (Agilent Technologies). Signaling activity above a previously established cut-off value was used to identify abnormal levels of EGFR, HER2 and c-Met signaling activity. For the xenograft study, OVCAR-4, an ovarian cancer cell line, determined to have abnormal HER2, EGFR, and c-Met signaling with the CELx MP Test, was studied. 40 female NSG mice were injected with two million OVCAR-4 cells. Mice were randomly assigned to either a control group that received Captisol excipient or a treatment group that received neratinib, tepotinib, or neratinib and tepotinib for 16 days. Results: Of the patient cell and cell lines samples tested ex vivo with the CELx MP test, 4 of 27 (15%; 95% CI=6%-32%) had hyperactive HER2 and c-Met signaling pathways. In the xenograft study, there was no significant difference in tumor volume between the control and tepotinib-treated or neratinib groups after 16 days of treatment. Tumor volumes relative to tumor size before treatment were reduced by 40% in the tepotinib + neratinib treated group. Conclusions: These findings suggest that a significant sub-group of ovarian cancer patients have abnormal ErbB and c-Met signaling activity that may respond to treatment with a combination of ErbB and c-Met inhibitors. A clinical trial to evaluate treatment response of this patient sub-set to combined c-Met and pan-HER inhibitors is warranted. Citation Format: Stefano Rossetti, Catherine Kuzmicki, Aaron Broege, Joanna Sabat, Salmaan Khan, Ian MacNeil, Brian Sullivan, Lance Laing. Hyperactive c-Met and ErbB signaling detected in a sub-group of ovarian patient tumors: Patient sub-group may benefit from c-Met and pan-HER combination therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3198.

Test identifies ovarian cancer patients with hyperactive c-Met and ErbB signaling tumors who may benefit from c-Met and pan-HER combination therapy.

e18038 Background: No sub-groups of ovarian cancer patients with clinically actionable ErbB genetic variants have yet been found. Measurement of ErbB signaling activity rather than genetic variants may identify ovarian cancer patients likely to benefit from ErbB targeted therapies. We have previously reported studies detecting dysregulated ErbB and c-Met signaling activity in 20%-25% of HER2-negative breast cancer patient tumors using the CELx Signaling Function Test. To determine whether ErbB or c-Met signaling dysregulation is involved in ovarian cancer, the CELx Test was adapted to analyze ovarian tumor cells. The current study set out to: 1) characterize c-Met and ErbB family signaling activity in ovarian patient tumor cells and tumor cell lines; 2) evaluate in vivo response to pan-HER and c-Met inhibitors in an ovarian tumor xenograft model. Methods: For the ex vivo studies, a set of fresh tumor specimens from 15 ovarian cancer patients and a set of 12 ovarian cancer cell lines was obtained. Cell samples were cultured from each. Live cell response to ErbB and c-Met agonists (NRG1b, EGF, or HGF) with or without an antagonist (2C4, a HER2 dimerization inhibitor or tepotinib, a c-Met kinase inhibitor) was measured using an xCELLigence impedance biosensor (Agilent Technologies). Signaling activity above a previously established cut-off value was used to identify abnormal levels of EGFR, HER2 and c-Met signaling activity. For the xenograft study, OVCAR-4, an ovarian cancer cell line, determined to have abnormal HER2, EGFR, and c-Met signaling with the CELx Test, was studied. 40 female NSG mice were each injected with two million cells. Mice were randomly assigned to either a control group or a treatment group that received neratinib, tepotinib, or neratinib and tepotinib for 16 days. Results: Of the patient cell and cell lines samples tested ex vivo with the CELx Test, 4 of 27 (15%; 95% CI = 6%-32%) had hyperactive HER2 and c-Met signaling pathways. In the xenograft study, tumor volume change was 40% less in the tepotinib + neratinib treated group than in the control arm change. There was no significant difference in tumor volume between the control and tepotinib or neratinib groups. Conclusions: These findings suggest that a significant sub-group of ovarian cancer patients have abnormal ErbB and c-Met signaling activity that may respond to treatment with a combination of ErbB and c-Met inhibitors. A clinical trial to evaluate treatment response of this patient sub-set to combined c-Met and pan-HER inhibitors is warranted.

Baseline and early 3D-CUBE volume reconstruction of locally advanced rectal cancer to predict tumor response after neoadjuvant chemotherapy.

To explore whether volumetric measurements of 3D-CUBE sequences based on baseline and early treatment time can predict neoadjuvent chemotherapy (NCT) efficacy of locally advanced rectal cancer (LARC). 73 patients with LARC were enrolled from February 2014 to January 2018. All patients underwent MRIs during the baseline period before NCT (BL-NCT) and the first month of NCT (FM-NCT), and tumor volume (TV) was measured using 3D-CUBE, and tumor volume reduction (TVR) and tumor volume reduction rate (TVRR) were calculated. In addition, tumor invasion depth, tumor maximal length, range of tumor involvement in the circumference of intestinal lumen and distance from inferior part of tumor to the anal verge were measured using baseline high-spatial-resolution T2-weighted MRIs. All patients were categorized into sensitive and insensitive groups based on post-surgical pathology after completion of the full courses of NCT. The receiver operating characteristic (ROC) curve was used to analyze the value of different MRI parameters in predicting efficacy of NCT. Statistically significant differences in TV of BL-NCT, TVR and TVRR from BL-NCT to FM-NCT were detected between sensitive and insensitive groups (P < 0.05, respectively). The areas under the curves (AUC) of ROC of TVR and TVRR in predicting efficacy of NCT (0.890 [95% CI, 0.795∼0.951], 0.839 [95% CI, 0.735∼0.915]) were significantly better than that of TV (0.660 [95% CI, 0.540∼0.767]) (P < 0.05, respectively). Reconstruction of 3D-CUBE volume in the first month of NCT is necessary, and both TVR and TVRR can be used as early predictors of NCT efficacy.