Changes In Tumor Volume Research Articles

Mathematical Model of Triple-Negative Breast Cancer in Response to Combination Chemotherapies.

Triple-negative breast cancer (TNBC) is a heterogenous disease that is defined by its lack of targetable receptors, thus limiting treatment options and resulting in higher rates of metastasis and recurrence. Combination chemotherapy treatments, which inhibit tumor cell proliferation and regeneration, are a major component of standard-of-care treatment of TNBC. In this manuscript, we build a coupled ordinary differential equation model of TNBC with compartments that represent tumor proliferation, necrosis, apoptosis, and immune response to computationally describe the biological tumor affect to a combination of chemotherapies, doxorubicin (DRB) and paclitaxel (PTX). This model is parameterized using longitudinal [18F]-fluorothymidine positron emission tomography (FLT-PET) imaging data which allows for a noninvasive molecular imaging approach to quantify the tumor proliferation and tumor volume measurements for two murine models of TNBC. Animal models include a human cell line xenograft model, MDA-MB-231, and a syngeneic 4T1 mammary carcinoma model. The mathematical models are parameterized and the percent necrosis at the end time point is predicted and validated using histological hematoxylin and eosin (H&E) data. Global Sobol' sensitivity analysis is conducted to further understand the role each parameter plays in the model's goodness of fit to the data. In both the MDA-MB-231 and the 4T1 tumor models, the designed mathematical model can accurately describe both tumor volume changes and final necrosis volume. This can give insight into the ordering, dosing, and timing of DRB and PTX treatment. More importantly, this model can also give insight into future novel combinations of therapies and how the immune system plays a role in therapeutic response to TNBC, due to its calibration to two types of TNBC murine models.

A clinical study on microwave ablation of multifocal (≤ 3) T1N0M0 papillary thyroid carcinoma.

To evaluate the feasibility, efficiency, and safety of microwave ablation (MWA) for T1N0M0 multifocal (≤ 3) papillary thyroid carcinoma (PTC). This was a retrospective study, and patients who underwent MWA for multifocal (≤ 3) PTC were reviewed between October 2016 and December 2020. After ablation, the changes in tumor size and volume, as well as the rate of technical success, tumor disappearance, disease progression, and complications were assessed. There were a total of 57 cases enrolled in the present study, which included 18 males and 39 females. The mean age was 44 ± 11 years (22-66 years); the mean follow-up time was 18 ± 11 months (6-48 months). Complete ablation was achieved in all enrolled cases. Therefore, the technical success rate was 100%. Due to expanding ablation, the MD and volume of the ablation zone, as well as the VRR, increased at the 1st and 3rd months after ablation and decreased at 12 and 18 months after ablation (p < 0.05 for all). The total complete tumor disappearance rate was 43.9% (25/57), including 54% (24/44) in the T1a subgroup vs. 7.7% (1/13) in the T1b subgroup (p = 0.003). The total disease progression rate was 7% (4/57), including 9.1% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.142). The overall complication rate was 5.3% (3/57), including 6.8% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.206). This preliminary study indicates that MWA is a safe and effective treatment for T1N0M0 multifocal (≤ 3) PTC. • MWA is a promising alternative method for T1N0M0 multifocal (≤ 3) PTC.

MNG-3 STRATIFICATION OF TUMOR GROWTH BY RISK FACTORS AND PREDICTED TUMOR VOLUME CURVES FOR SUPRATENTORIAL MENINGIOMAS

Abstract Background The natural history of meningiomas is still unclear, and no guidelines have been established based on objective indices regarding the necessity and timing of therapeutic intervention.Objective: We attempted to provide statistics on the characteristics of tumor volume change, stratify tumor growth by risk factors, and generate a predictive tumor volume curve based on the statistics, with the aim of describing the natural history of meningiomas. Methods 313 cases were included in the study, with the origin of meningioma being the circumflex and parasagittal sinus areas and the cerebral sickle region, and with multiple MRI scans performed at intervals of at least 3 months. Relative growth rate (RGR) and annual volume change (AVC) were calculated by measuring tumor volume, and the patients were classified into three groups according to the combination of gender, age, and MRI T2WI signal intensity, and compared. Results The median RGR and AVC of the entire cohort were 6.1% and 0.20 cm3/year, respectively, and there were significant differences between groups in gender (p=0.018) and MRI T2WI (p &amp;lt; 0.001) for RGR and tumor location (p=0.025) and initial tumor volume (p &amp;lt; 0.001)for AVC. The median RGR and AVC in the classification were 17.5% and 1.05 cm3/year for the very high growth group, 8.2% and 0.33 cm3/year for the high growth group, and 3.4% and 0.04 cm3/year for the low growth group, showing significant differences between the groups (p &amp;lt; 0.001). The predicted tumor volume curve showed an average 2.24-fold or 5.24 cm3 increase in volume over 5 years in the very high-growth group, while little tumor volume change was observed in the low-growth group. Conclusion The combination of growth risk factors allowed stratification of tumor growth and provided a predictive tumor volume curve for each county. The results may assist in the treatment of meningiomas.

Automated segmentation of lungs and lung tumors in mouse micro-CT scans.

Here, we have developed an automated image processing algorithm for segmenting lungs and individual lung tumors in invivo micro-computed tomography (micro-CT) scans of mouse models of non-small cell lung cancer and lung fibrosis. Over 3000 scans acquired across multiple studies were used to train/validate a 3D U-net lung segmentation model and a Support Vector Machine (SVM) classifier to segment individual lung tumors. The U-net lung segmentation algorithm can be used to estimate changes in soft tissue volume within lungs (primarily tumors and blood vessels), whereas the trained SVM is able to discriminate between tumors and blood vessels and identify individual tumors. The trained segmentation algorithms (1) significantly reduce time required for lung and tumor segmentation, (2) reduce bias and error associated with manual image segmentation, and (3) facilitate identification of individual lung tumors and objective assessment of changes in lung and individual tumor volumes under different experimental conditions.

A Pilot Study of Intralesional Injection of Triamcinolone Acetonide for Desmoid Tumors: Two-Year Outcomes.

The purpose of this pilot study was to examine the clinical efficacy and safety of serial triamcinolone injections for the treatment of desmoid tumors. Nine patients were enrolled into this prospective study and underwent three serial ultrasound-guided triamcinolone injections (120 mg) at 6-week intervals. MRI was compared at baseline and every 6 months, out to 24 months. Safety and tolerability were assessed by clinical evaluation and questionnaires, including the 12-item short form survey (SF-12), visual analog scale (VAS), and desmoid patient-reported outcome (PRO) tool. At 24 months, 8 (88.9%) patients demonstrated a reduction in the volume of their tumor while 1 (11.1%) enlarged. Median tumor volume change was -26.9% (-81.1% to 34.6%; P = 0.055) All 9 tumors remained stable based on World Health Organization criteria, whereas 2 (22.2%) demonstrated partial response based on RECIST. There was a significant decrease in the tumor:muscle postcontrast mean signal intensity ratio at 6 months (P = 0.008) and 24 months (P = 0.004). There was a similar decrease in the tumor:muscle T2 mean signal intensity ratio at 24 months (P = 0.02). We found no difference in the SF-12 and VAS scores, but there were significant improvements in the desmoid PRO. Treatment of desmoid tumors with serial triamcinolone injections appears safe and well tolerated by patients, with a 22% partial response based on RECIST. Further research is needed to confirm our results and determine factors predictive of response.

Proteogenomic landscape and clinical characterization of GH-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors

The clinical characteristics of growth hormone (GH)-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors (GHomas/somatotroph PitNETs) vary across patients. In this study, we aimed to integrate the genetic alterations, protein expression profiles, transcriptomes, and clinical characteristics of GHomas/somatotroph PitNETs to identify molecules associated with acromegaly characteristics. Targeted capture sequencing and copy number analysis of 36 genes and nontargeted proteomics analysis were performed on fresh-frozen samples from 121 sporadic GHomas/somatotroph PitNETs. Targeted capture sequencing revealed GNAS as the only driver gene, as previously reported. Classification by consensus clustering using both RNA sequencing and proteomics revealed many similarities between the proteome and the transcriptome. Gene ontology analysis was performed for differentially expressed proteins between wild-type and mutant GNAS samples identified by nontargeted proteomics and involved in G protein–coupled receptor (GPCR) pathways. The results suggested that GNAS mutations impact endocrinological features in acromegaly through GPCR pathway induction. ATP2A2 and ARID5B correlated with the GH change rate in the octreotide loading test, and WWC3, SERINC1, and ZFAND3 correlated with the tumor volume change rate after somatostatin analog treatment. These results identified a biological connection between GNAS mutations and the clinical and biochemical characteristics of acromegaly, revealing molecules associated with acromegaly that may affect medical treatment efficacy.

Effect of Guizhi Fuling Capsule on Apoptosis of Myeloma Cells Through Mitochondrial Apoptosis Pathway.

To observe the effects of Guizhi Fuling Capsule (GZFLC) on myeloma cells and explore the mechanisms. MM1S and RPMI 8226 cells were co-cultured with different concentrations of serum and the cell experiments were divided into negative (10%, 20% and 40%) groups, GZFLC (10%, 20%, and 40%) groups and a control group. Cell counting kit-8 (CCK-8) assays and flow cytometry were used to detect the viability and apoptosis levels of myeloma cells. The effects on mitochondria were examined by reactive oxygen specie (ROS) and tetrechloro-tetraethylbenzimidazol carbocyanine iodide (JC-1) assays. Western blot was used to detect the expression of B cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), cleaved caspase-3, -9, cytochrome C (Cytc) and apoptotic protease-activating factor 1 (Apaf-1). RPMI 8226 cells (2 × 107) were subcutaneously inoculated into 48 nude mice to study the in vivo antitumor effects of GZFLC. The mice were randomly divided into four groups using a completely randomized design, the high-, medium-, or low-dose GZFLC (840, 420, or 210 mg/kg per day, respectively) or an equal volume of distilled water, administered daily for 15 days. The tumor volume changes in and survival times of the mice in the GZFLC-administered groups and a control group were observed. Cytc and Apaf-1 expression levels were detected by immunohistochemistry. GZFLC drug serum decreased the viability and increased the apoptosis of myeloam cells (P<0.05). In addition, this drug increased the ROS levels and decreased the mitochondrial membrane potential (P<0.01). Western blot showed that the Bcl-2/Bax ratios were decreased in the GZFLC drug serum-treated groups, whereas the expression levels of cleaved caspase-3, -9, Cytc and Apaf-1 were increased (all P<0.01). Over time, the myeloma tumor volumes of the mice in the GZFLC-administered groups decreased, and survival time of the mice in the GZFLC-administered groups were longer than that of the mice in the control group. Immunohistochemical analysis of tumor tissues from the mice in the GZFLC-administered groups revealed that the Cytc and Apaf-1 expression levels were increased (P<0.05). GZFLC promoted apoptosis of myeloma cells through the mitochondrial apoptosis pathway and significantly reduced the tumor volumes in mice with myeloma, which prolonged the survival times of the mice.

Computational analysis of 5-fluorouracil anti-tumor activity in colon cancer using a mechanistic pharmacokinetic/pharmacodynamic model.

5-Fluorouracil (5-FU) is a standard chemotherapeutic agent to treat solid cancers such as breast, colon, head, and neck. Computational modeling plays an essential role in predicting the outcome of chemotherapy and developing optimal dosing strategies. We developed an integrated mechanistic pharmacokinetics/pharmacodynamics (PK/PD) model examining the influence of 5-FU, as an S-phase specific double-strand break (DSB)-inducing agent, on tumor proliferation. The proposed mechanistic PK/PD model simulates the dynamics of critical intermediate components and provides the accurate tumor response prediction. The integrated model is composed of PK, cellular, and tumor growth inhibition (TGI) sub-models, quantitatively capturing the essential drug-related physiological processes. In the cellular model, thymidylate synthase (TS) inhibition, resultant deoxynucleoside triphosphate (dNTP) pool imbalance, and DSB induction are considered, as well as 5-FU incorporation into RNA and DNA. The amount of 5-FU anabolites and DSBs were modeled to drive the kinetics of the pharmacological tumor response. Model parameters were estimated by fitting to literature data. Our simulation results successfully describe the kinetics of the intermediates regulating the 5-FU cytotoxic events and the pattern of tumor suppression. The comprehensive model simulated the tumor volume change under various dose regimens, and its generalizability was attested by comparing it with literature data. The potential causes of the tumor resistance to 5-FU are also investigated through Monte Carlo analysis. The simulation of various dosage regimens helps quantify the relationship between treatment protocols and chemotherapy potency, which will lead to the development of efficacy optimization.

Upconversion Optogenetic Engineered Bacteria System for Time-Resolved Imaging Diagnosis and Light-Controlled Lymphoma Therapy

Purpose Engineering bacteria can achieve targeted and controllable cancer therapy by utilizing synthetic biology technology and the characteristics of tumor microenvironment. Besides, the accurate tumor diagnosis and visualization of treatment process are also vital for bacterial therapy. In this study, lymphoma was used as a model. A series of experiments in vitro and in vivo were used to test the tumor targeting and accurate drug release ability of the drug system, to evaluate its visual diagnosis and antitumor effect, and to evaluate the safety of the live biotherapeutics and carrier system. Results As shown in Figure 1, light control engineered bacteria system based on upconversion nanoparticles (UCNP) mediated time-resolved imaging (TRI) was constructed for lymphoma theranostic and therapy. The engineered bacteria were named as EcN-pDawn-φx174E/TRAIL, which lysed by blue light irradiation and then released tumor apoptosis-related inducing ligand (TRAIL). When the tumor was irradiated by blue light, TRAIL was released from bacteria to trigger tumor cell death. And then, UCNP with short luminous lifetime (UCNP(s)) were connected with anaerobic probiotics EcN-pDawn-φx174E/TRAIL to prepare EcN@UCNP(s), which targets tumor through the hypoxia targeting ability of EcN. UCNP with long luminous lifetime were modified with folic acid (FA) to prepare FA@UCNP, which targets tumor through the active targeting ability of FA. EcN@UCNP(s) and FA@UCNP were injected through tail vein, and both of them were co-located at tumor site. They can be distinguished with each other and used to precisely indicate the presence of tumor by TRI. In vitro results showed that the released TRAIL from EcN could induce tumor cell death. In addition, the EcN-pDawn-φx174E/TRAIL+blue group showed the strongest therapeutic effect, which laid foundations for in vivo light control tumor treatment. Subcutaneous Raji, U937 and Jurkat tumor model was constructed to evaluate the blue light control treatment effects. As indicated in bio-distribution studies, there were no bacteria accumulation in heart, spleen and lung tissues, the most bacteria were accumulated in tumor and they expanded over time. To explore whether the bacteria at the tumor site can function normally, the EcN-GFP were used for intuitive observation. The research demonstrated that GFP was expressed in tumor tissues, indicating that EcN-GFP@UCNP(s) targeted tumor, survived and expressed proteins. Besides, the TRAIL expression in tumor tissue was studied by ELISA assay, which showed that TRAIL could be normally expressed and released in therapy group. The mice weight and tumor volume changes were measured every two days. There were no obvious changes in body weight of all mice. In addition, the blood routine and blood biochemical analysis were carried out after the experiment completed, and all indicators were within the normal range. And then HE staining of main organs in all groups explained the biosafety of these therapeutic materials The tumor volume changes in each group were illustrated. In the blue light control tumor inhibition experiment, the therapy group displayed the smallest tumor volume (402 mm3), while the tumor volume in dark group was 1999 mm3, which was similar to that in control (2120 mm3) and FA@UCNP(l) group (2033 mm3). The therapy group revealed the highest tumor growth inhibition compared with other groups. The changes of cytokine concentration in tumor tissues were also measured by ELISA assays. Obviously increased TNF-α, IFN-γ and IL-6 level were observed in therapy group. Besides, more tumor apoptosis was observed in therapy group. All these findings indicated that EcN-pDawn-φX174E/TRAIL could inhibit tumor growth in a blue light-dependent manner. Conclusion In this paper, upconversion optogenetic engineered bacteria system was developed for time-resolved imaging diagnosis and light-controlled cancer therapy. The system had the characteristics of accurate diagnosis and controllable treatment. Both EcN@UCNP(s) and FA@UCNP target tumor tissue and the colocation accurately indicated the existence and location of tumor by TRI. In addition, EcN-pDawn-φX174E/TRAIL accumulated at tumor site were induced by blue light to lyse and release TRAIL, thus inducing tumor cell death. We expect that this engineered bacteria system provides a new technology for intelligent bacterial therapy and the construction of lymphoma theranostics. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

NIMG-68. IMAGING PHOSPHOLIPID BIOSYNTHESIS ENABLES NON-INVASIVE ASSESSMENT OF BRAIN TUMOR RESPONSE TO THERAPY

Abstract Elevated phospholipid biosynthesis is a metabolic hallmark of cancer. Due to the high membrane turnover associated with uncontrolled proliferation, tumor cells invariably upregulate phospholipid biosynthesis. Choline is a dietary nutrient that is phosphorylated to phosphocholine (PC) and subsequently incorporated into phosphatidylcholine, which is the primary membrane phospholipid in mammalian cells. Choline kinase α (CKα) is the key enzyme in this pathway and its expression is elevated in most cancers. Identifying non-invasive methods of imaging CKα activity, can, therefore, enable assessment of tumor burden and response to therapy. Deuterium magnetic resonance spectroscopy (DMRS) following administration of 2H-labeled substrates recently emerged as a simple, robust, clinically translatable method of assessing metabolic activity in vivo. The goals of the current study were to determine whether DMRS-based assessment of PC production from [2H9]-choline tracks CKα activity and to establish the utility of [2H9]-choline for glioma imaging in vivo. First, we show that [2H9]-choline metabolism to PC can be observed in live patient-derived glioma cells (GBM6 and BT88). Silencing CKα abrogates PC production from [2H9]-choline in both GBM6 and BT88 models, thereby confirming that [2H9]-choline provides a readout of CKα activity. Next, we examined the ability of [2H9]-choline to monitor tumor burden and response to therapy in vivo. [2H9]-choline metabolism to PC can be observed in mice bearing orthotopic patient-derived GBM6 or BT257 tumors, but not in tumor-free healthy controls. Importantly, following treatment of mice bearing orthotopic BT257 tumors with temozolomide, which is standard of care for glioma patients, PC production from [2H9]-choline is reduced at early timepoints when changes in tumor volume cannot be detected by anatomical imaging. Taken together, our studies, for the first time, identify [2H9]-choline as a probe of CKα activity and highlight its ability to assess tumor burden and early response to therapy, which is a challenge in glioma imaging.

RF07 | PSUN355 Downstream Targets of the Steroidogenic Factor-1 (SF-1) Antagonist OR-449 in PDX Models of ACC

Abstract Background Adrenocortical cancer (ACC) is a rare endocrine malignancy frequently diagnosed at an advanced stage when prognosis is dismal. Mitotane, the only approved therapy for locally advanced or metastatic disease, is minimally effective, and recent clinical trials with multi-kinase inhibitors or immunotherapies have been disappointing. OR-449 is a potent, selective, and orally bioavailable small molecule antagonist to steroidogenic factor-1 (SF-1 or NR5A1), a nuclear receptor and a transcription factor essential for the growth and development of the adrenal gland. SF-1 was recently described as a candidate "master transcription factor" in adult ACC (1). We previously reported that OR-449, dosed orally at 30 mg/kg for 28 days, completely blocked the growth of SJ-ACC3, a pediatric ACC patient-derived tumor xenograft (PDX), in immunocompromised mice. To help identify biomarkers for following the action of OR-449 in patient tumors, we evaluated a second pediatric ACC PDX, SW1939, which has high SF-1 expression and responded to OR-449 (10, 30 or 100 mg/kg) with inhibition of tumor growth and improved event-free survival over 24 days of dosing (an event is a 4-fold increase in tumor volume). Methods We first measured circulating steroids, steroid precursors and steroid sulfates in SW1939 tumor-bearing mice with or without OR-449 treatment using liquid chromatography/tandem mass spectrometry. Second, we investigated common pathways of gene regulation by OR-449 in SW1939 and SJ-ACC3 tumors by RNAseq after seven days of dosing (100 mg/kg or 30 mg/kg, respectively). Results Cortisol, DHEAS, steroid precursors (11-deoxycortisol, 17OH-progesterone, 17OH-pregnenolone) and sulfated Δ5 steroid precursors (pregnenolone sulfate, 17OH-pregnenolone sulfate, androstenediol-sulfate) were elevated in serum from SW1939 tumor-bearing mice compared to CD-1 non tumor-bearing mice, consistent with tumor-derived origin. Moreover, DHEAS, pregnenolone sulfate, 17OH-pregnenolone sulfate and androstenediol-sulfate were significantly suppressed (12-fold, 7.6-fold, 10.6-fold and 4.4-fold, respectively) following administration of OR-449 (100 mg/kg/day for 24 days) in SW1939 tumor-bearing mice. Final tumor weights were ∼2-fold lower than controls, indicating that circulating steroid reduction was disproportionately greater than the change in tumor volume. Global gene expression was significantly altered following 7-day exposure to OR-449 in both tumors. Significantly, PAPSS2 and SULT2A1 within the sulfation pathway were down-regulated in both SW1939 (2.3-fold and 1.2-fold, respectively) and SJ-ACC3 (1.6-fold and 5-fold, respectively). Conclusions OR-449 reduces steroid production, alters gene expression, and suppresses growth of two PDX models of ACC in mice. Tumor gene expression and steroid regulation by OR-449 are currently under investigation in other pediatric and adult ACC PDX models to evaluate these endpoints as potential biomarkers of SF-1 receptor engagement for initial clinical trials of OR-449 in ACC. Reference: (1) Corces et al., Science. 2018 Oct 26;362(6413): eaav1898; Reddy et al., Sci Adv. 2021 Nov 26;7(48): eabf6123. Presentation: Saturday, June 11, 2022 1:06 p.m. - 1:11 p.m., Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

OR27-3 Long-Term Results from the Phase III LINC 4 Study: Osilodrostat Maintained Normal Mean Urinary Free Cortisol in Patients with Cushing's Disease, with a Favorable Safety Profile

Abstract Background Osilodrostat, a potent oral 11β-hydroxylase inhibitor, provided rapid and sustained normalization of mean urinary free cortisol (mUFC) in patients with Cushing's disease (CD) during the 48-week (W) core period of LINC 4 (NCT02697734), and was well tolerated. We report long-term efficacy and safety results from the LINC 4 core and extension phases combined. Methods 73 adults with CD and mUFC &amp;gt;1.3× the upper limit of normal (ULN) were enrolled. LINC 4 comprised a 12W, randomized, double-blind, placebo-controlled period followed by 36W of open-label osilodrostat. At W48, patients could enter an optional extension. Dose adjustments were permitted based on efficacy/tolerability (range during open-label treatment 1–30 mg bid). LINC 4 ended when all patients transitioned to a separate long-term safety study (not reported) or discontinued treatment. Efficacy/safety are reported for all patients unless otherwise stated, and excludes data collected during W1–12 for placebo recipients. Results Of the 65 patients who completed the core phase, 60 entered the extension. Median (range) osilodrostat exposure from core baseline to study end was 87.1 (2–127) W; median average (IQR) dose was 4.6 (3.7–9.2) mg/day. 15 patients discontinued osilodrostat; 7 after W48 (6 because of adverse events [AEs]). The proportion of patients with normal mUFC (≤138 nmol/24h [50 µg/24h]) was 68.5% (n=50/73) at W48, 61.5% (n=40/65) at W72 and 72.4% (n=42/58) at the end-of-treatment extension (EOT) visit. Median mUFC decreased from 2.5×ULN (core baseline) to 0.5×ULN (W48 and W72), to 0.4×ULN (EOT). Median late-night salivary cortisol decreased from 2.8×ULN (core baseline) to 1.2×ULN (W48 and W72), to 1.1×ULN (EOT).The most common AEs during the entire study were decreased appetite (46.6%), arthralgia (45.2%), fatigue (39.7%), nausea (37.0%), headache (34.2%) and dizziness (30.1%). Hypocortisolism- and adrenal-hormone-precursor-accumulation-related AEs occurred in 28.8% (21/73) and 61.6% (45/73) of patients during the entire study, less frequently in the extension than the core. Most were grade 1/2 and resolved with dose reduction/interruption and/or concomitant medication. During the extension, hirsutism and acne were reported as AEs by 1 and 0 patients, respectively.Median ACTH increased from 1.1×ULN (core baseline) to 3.0×ULN (W48), to 3.6×ULN (W72), to 3.5×ULN (EOT). Median change (95% CI) in pituitary tumor volume (assessed by MRI) from core baseline to last available assessment was 4.0 mm3 (−24.1–169.8); pituitary-tumor-enlargement-related AEs led to drug discontinuation in 2 and 0 patients during the core and extension, respectively. No trend was observed between tumor volume change and osilodrostat dose. Conclusion Osilodrostat provided long-term control of cortisol production during LINC 4. Fewer AEs related to hypocortisolism and accumulation of adrenal-hormone-precursors occurred during the extension than during the core. Osilodrostat is an effective and well-tolerated long-term treatment option for CD patients. Presentation: Tuesday, June 14, 2022 10:15 a.m. - 10:30 a.m.

Intravoxel Incoherent Motion MRI and PET in Locally Advanced Cervical Carcinoma Undergoing Concurrent Chemoradiation Therapy

<h3>Purpose/Objective(s)</h3> Dynamic contrast enhanced (DCE) CT or MRI and FDG PET have been used to evaluate the impact of tumor perfusion and metabolism on the course and effectiveness of concurrent chemoradiation therapy (CCRT) for cervical cancer. Combining perfusion and metabolic measures allows better identification of radioresistant sub-volumes: however, use of contrast and additional dose are barriers to frequent dual perfusion-metabolic imaging. Here, we investigated a contrast-free, non-ionizing alternative to DCE: intravoxel incoherent motion (IVIM) MRI which provides both perfusion and diffusion measurements. Our objective was to evaluate changes of PET and IVIM parameters in cervical cancer patients before and during CCRT and to correlate these parameters and their changes with tumor volume response during CCRT. <h3>Materials/Methods</h3> Pre- and on-treatment IVIM scans were performed on 15 cervical cancer patients undergoing definitive chemoradiation (median [range] age: 66 [29 to 85]; FIGO: 1 IB1, 1 IIA, 3 IIB, 1 IIIB, 1 IIIC, 5 IIIC1, 2 IIIC2, 1 IVA; hist: 11 squamous cell carcinoma, 3 endocervical adenocarcinoma, 1 large cell neuroendocrine carcinoma), of whom 14 also underwent pre-treatment PET scans. The on-treatment MRI occurred generally during the last week or shortly after completing EBRT. Diffusion weighted images (DWIs) were acquired at 3T scanners using a free-breathing single shot spin echo planar imaging (EPI) sequence. IVIM MRI maps were generated by Bayesian fitting of a two-compartment IVIM model to the DWIs. Three-dimensional co-registered maps of PET standardized uptake value (SUV) and IVIM diffusion coefficient (D), perfusion fraction (f), and pseudo-diffusion coefficient (D*) were generated. Summary statistics (mean +/- standard deviation) for these and other imaging parameters were calculated pre- and on-treatment. Univariate analysis was performed to determine relationships between relative change in gross tumor volume (ΔGTV) and pre-treatment imaging measurements. <h3>Results</h3> In tumors, pre- versus on-treatment values significantly changed for the following parameters: ΔGTV (66.8 +/- 43.2 vs. 32.0+/-23.0 ml, p<.001) and D (0.00109 +/- 0.00023 vs. 0.00120 +/- 0.00026 mm²/s, p=.02). The perfusion fraction f increased and D* decreased, but not significantly (f: 0.127 +/- 0.022 vs. 0.154 +/- 0.057 %, p=.07, D*: 0.0137 +/- 0.0035 vs. 0.0133 +/- 0.0039 mm²/s, p=.6). Pre-treatment SUV_max (r=.76, p=.002) and SUV_mean (r=.70, p=.007) were positively related with ΔGTV, while pre-treatment f, D*, and D were negatively but not significantly related with ΔGTV (r=-.44, p=.1; D*: r=-.14, p=.6; D: r=-.12, p=.7). <h3>Conclusion</h3> Both perfusion fraction and diffusion coefficient IVIM increased in locally advanced cervical carcinoma patients undergoing CCRT – reflecting changes in the tumor microenvironment during treatment. These weak relationships observed here suggest a potential complementary role and motivating the combined use of these modalities for tumor characterization.

A retrospective investigation of the relationship between neuroblastoma response to anti-GD2 monoclonal antibodies and exposure to opioids for pain management.

Recent increased awareness and research studies reflect possible associations between opioid exposure and cancer outcomes. Children with neuroblastoma (NB) often require opioid treatment for pain. However, associations between tumor response to chemotherapy and opioid exposure have not been investigated in clinical settings. This is a single-institution retrospective review of patients with NB treated between 2013 and 2016. We evaluated opioid consumption quantified in morphine equivalent doses (mg/kg) based on nurse- or patient-controlled analgesia during antibody infusions. We also analyzed their associations with change in primary tumor volume and total tumor burden. Of 42 patients given opioids for pain related to anti-disialoganglioside monoclonal antibodies (anti-GD2 mAb), data completion was achieved for 36, and details of statistical analyses were entered. Median total weight-based morphine equivalent (over 8days) was 4.71mg/kg (interquartile range 3.49-7.96). We found a statistically insignificant weak negative relationship between total weight-based morphine equivalents and tumor volume ratio (correlation coefficient -.0103, p-value .9525) and a statistically insignificant weak positive relationship between total weight-based morphine equivalent and Curie score ratio (correlation coefficient .1096, p-value .5247). Our study found no statistically significant correlation between opioid consumption and natural killer (NK) cell-mediated killing of NB cells as measured by effects on tumor volume/tumor load.

TRIBBLES1 (TRIB1) Pseudokinase Induces Treatment Resistance in GBM by Promoting Survival of Tumor Cells through the Akt Pathway

<h3>Purpose/Objective(s)</h3> Glioblastoma (GBM; WHO grade IV) is the most aggressive form of glioma with a dismal 5-year survival rate. The current therapies are largely ineffective and therapy resistance is commonly encountered. Therefore, there is an urgent need to identify druggable therapeutic targets in GBM. In this study we identified TRIB1, a Ser/Thr pseudokinase that functions as a scaffold to initiate Ubiquitin Proteasome System-mediated degradation of target proteins in the cell. It has also been shown to activate the MAPK and Akt signaling cascades in various cell types. Reports also suggest that TRIB1 contributes to chemotherapy resistance in various cancers. Therefore, we evaluated the role of TRIB1 in GBM cell proliferation/ survival and its contribution to therapy resistance. <h3>Materials/Methods</h3> We utilized patient-centered reverse translational approach to identify novel therapeutic targets. To this end, TRIB1 was identified by statistical association (Cox regression analysis) of the patient-derived mRNA profiling data publicly available from TCGA GBM cohort. TRIB1 was functionally validated <i>in vitro</i> by generating stable overexpression cell lines by antibiotic selection. TRIB1 was conditionally knocked down by doxycycline induction. Co-immunoprecipitation was performed to evaluate protein-protein interactions. Protein levels were detected by western blotting. Site-directed mutagenesis was performed to mutate specific amino acid. Patient derived primary cell lines overexpressing the wild type and mutant (W337A) Trib1 transgenes were injected intracranially to create tumors in nude mice. Changes in tumor volume and overall survival (OS) were determined. <h3>Results</h3> The mRNA profiling of TCGA GBM cohort revealed that increased <i>TRIB1</i> gene expression was associated with worse OS of GBM patients (HR=1.3 (1.0-1.5); P=0.019). Mice bearing TRIB1 transgene overexpressing tumors had highest tumor volume and lowest OS whereas mice bearing TRIB1-W337A tumors had the highest OS and lower tumor volume when measured. We also observed that overexpression of TRIB1 caused a decrease in apoptosis of primary GBM cell lines after RT and TMZ treatments <i>in vitro</i>. Overexpression of TRIB1 also increased the phosphorylation/activation of Akt in patient derived primary cell lines. Akt activation was similarly decreased after TRIB1 knockdown. TRIB1 bound directly to Akt in these cells. Following PI3K inhibition, Akt phosphorylation was detected to a greater level in TRIB1 overexpressing cells. <h3>Conclusion</h3> Our data suggest that heightened expression of TRIB1 in GBM cells contributes to RT/TMZ resistance by activating the prosurvival Akt signaling cascades. Therefore, targeting TRIB1 mediated Akt activation could provide a therapeutic benefit over targeting Akt directly, which may reduce Akt's oncogenic signal without risking the toxicity associated with available Akt- specific inhibitors.

Quantifying the Abscopal Effect in Breast Cancer Using Granzyme B PET Imaging

<h3>Purpose/Objective(s)</h3> Radiation can alter the tumor microenvironment and produce a corresponding immune response in tumors that have not been irradiated by generating a local inflammatory response and enhancing recognition of distant tumor cells, which is termed the "abscopal effect". We previously designed a positron emission tomography (PET) tracer, [⁶⁸Ga]-NOTA-GZP, which non-invasively detects granzyme B, a cytotoxic protease released by cytotoxic CD8⁺ lymphocytes and NK cells that initiates apoptosis of target tumor cells. [⁶⁸Ga]-NOTA-GZP PET imaging has been previously demonstrated to be predictive of response to checkpoint blockade in murine models, and is currently in clinical trials. We hypothesized that the abscopal effect could be induced by a single fraction of 12Gy irradiation and quantified by [⁶⁸Ga]-NOTA-GZP PET imaging. <h3>Materials/Methods</h3> To test this hypothesis, 4T1 breast cancer cells were implanted bilaterally in the mammary fat pad and one of the tumors received a single fraction of 12Gy irradiation followed by combination of PD-1 and CTLA-4 blockade concurrently. Tumor growth of the irradiated and contralateral tumors was measured and compared to irradiation only, immunotherapy only and control groups. Changes in granzyme B were assessed with [⁶⁸Ga]-NOTA-GZP PET imaging every three days until day 9. <h3>Results</h3> From days 0 to 9, there was no obvious change of PET uptake in the control and immunotherapy only groups. However, for the irradiation group and concurrent combination treatment group, PET uptake of the irradiated side increased slightly but not significantly. A significant elevation in the non-irradiated tumor of concurrent combination treatment group (p<0.05) was observed on day 9. Accordingly, a single fraction of 12Gy irradiation caused growth delay of the primary tumors (57.94±20.42 mm³) but had no effect on the contralateral tumors outside the radiation field (782.61±16.37 mm³) by day 30. Additionally, no tumor control was observed in the immunotherapy only group (p=0.7641). For the concurrent combination treatment group, both the irradiated tumor (17.02±5.71 mm³, p <0.0001) and the non-irradiated tumor volume decreased significantly (23.059±1.70 mm³, p <0.0001), consistent with the abscopal effect. The mean number of lung metastasis was lower in concurrent combination treatment group than other groups (p=0.037). <h3>Conclusion</h3> Concurrent combination treatment of a single fraction of 12Gy irradiation and PD-1 and CTLA-4 blockade activated the abscopal effect on non-irradiated tumors. [⁶⁸Ga]-NOTA-GZP PET imaging was able to non-invasively quantify the abscopal effect prior to subsequent tumor volume changes. This clinically relevant non-invasive approach is a promising potential tool to guiding combination radiation and immunotherapy to better understand and activate the abscopal effect in patients.

Tumor Volume Regression of Rectal Cancer in Daily MRI during Preoperative Chemoradiotherapy with Capecitabine

<h3>Purpose/Objective(s)</h3> Although cone beam computed tomography (CBCT) has been available for over a decade, the pattern of tumor volume change in rectal cancer during preoperative concurrent chemoradiotherapy (CCRT) has been under the veil due to poor soft tissue contrast of registration CBCT. This study was conducted to investigate daily rectal tumor volume change using registration magnetic resonance imaging (MRI). <h3>Materials/Methods</h3> Patients diagnosed with cT3-4 and/or cN+ rectal adenocarcinoma undergoing preoperative CCRT with capecitabine on the pelvis up to 50 Gy in 25 daily fractions from November 2018 to June 2019 were consecutively included. Rectal tumor volume was uniformly measured by single physician (YKK) in daily 0.35T MRI obtained with MR-guided linear accelerator. The mean +/- standard deviation (SD) of daily tumor volume (cc), difference of tumor volume between first fraction and daily fraction (baseline tumor volume at first fraction – daily tumor volume), and tumor volume reduction rate (%, [baseline tumor volume at first fraction – daily tumor volume]/baseline tumor volume at first fraction x 100) were calculated. Statistical significance of differences were tested using the Wilcoxon's signed rank test and paired t-test. <h3>Results</h3> Twenty patients were included. Median age was 64 and majority of the patients were male (90%). Most tumors were T3 (70%) and N1-2 (95%). Tumors were located median 6.9 cm (range: 1 – 12) above anal verge. Median follow-up was 32 months (range: 2.5 – 36.8) and 4 patients had recurred at the time of analysis (2 local and 2 distant). Tumor volume steadily regressed with daily administration of CCRT (mean 2.47 +/- 4.46 cc; Figure 1). Significant tumor volume reduction compared to baseline was observed from 4^th fraction (mean 13.95 +/- 17.78 cc; <i>P</i> < 0.0001). The difference of tumor volume between baseline and the last fraction was mean 46.62 +/- 56.01 cc (<i>P</i> < 0.0001). The tumor volume reduction rate was significantly increased since 4^th fraction (mean 16.64 +/- 10.9 %; <i>P</i> < 0.0001). The tumor volume reduction rate at the last fraction was – 68.18 +/- 15.68 % (<i>P</i> < 0.0001). <h3>Conclusion</h3> For the first time, this study demonstrated daily tumor volume regression in preoperative rectal CCRT with capecitabine using daily MRI. Steady pattern of tumor regression may be explained in part by daily administration of capecitabine. Based on the hypothesis-generating observation, this study may warrant initiation of further investigations on rectal tumor volume change with CCRT using daily MRI.

Assessment of Interfraction Change in Gross Tumor Volume of Anal Carcinoma Patients Undergoing Curative Chemoradiotherapy

<h3>Purpose/Objective(s)</h3> Radiation with concurrent chemotherapy (CRT) represents standard definitive therapy for anal cancer. CRT protocols result in excellent local control but are associated with significant acute and late morbidity. Adaptive planning techniques may allow for decrease in treatment volume and reduce toxicity. In this study, we used serial MRI scans to assess changes in gross tumor volume (GTV) during curative CRT. <h3>Materials/Methods</h3> Since 2019, we have instituted a REB-approved prospective registry study of de-escalated radiotherapy for patients undergoing CRT for anal cancer. Patients received a total dose of 45-63 Gy in 25-35 fractions with concurrent Capecitabine and a single dose of Mitomycin-C on day 1. In addition to pre-treatment (pre-tx) CT and MR simulation, patients also underwent MR simulation at fraction 11 (fx11) and fraction 21 (fx21). The GTV was contoured separately on individual axial T2 sequences. Median (inter-quartile-range) was used for descriptive statistics and the Mann-Whitney-Wilcoxon was used between groups of interfractional contours to determine statistically significant differences in tumor size between fractions. The Kruskal-Wallace test was used to determine significance between all 3 GTV volumes. P-values of <0.05 were considered statistically significant. <h3>Results</h3> A total of 24 patients were accrued. All patient completed RT without interruptions. All 24 had pre-tx MRI. During CRT course, 22 had a second MRI scan (fx11), and 19 had a third (fx21) scan. Table 1 shows the median (IQR) pre-tx GTV and the absolute and percent reduction in the GTV at fx11 and fx21 compared to pre-treatment GTV. Median (IQR) reduction in GTV between pre-tx and fx11 and fx21 MRI was 6.1cc (3.8-12.1) and 7.8cc (5.7-14.6), respectively. Median reduction in GTV between fx11 and fx21 was 2.9cc (1.3-6.6). After normalizing volumes as the percentage of pre-tx GTV, median (IQR) volume was 62.5% (51.6-69.7) (p<0.001) at fx11 and 43.6% (34.2-55.6) (p<0.001) at fx21. Based on Kruskal-Wallace test, overall change between GTVs at all 3 time points was found to be significant, p=0.042. <h3>Conclusion</h3> For patients undergoing CRT for anal cancer, there appears to be an early and significant reduction in the tumor volume over time. This study helps define planning adaptation parameters using serial MRI during CRT and will inform strategies to reduce normal tissue exposure

Chlorin e6-loaded goat milk-derived extracellular vesicles for Cerenkov luminescence-induced photodynamic therapy.

Photodynamic therapy (PDT) is a promising cancer treatment strategy with rapid progress in preclinical and clinical settings. However, the limitations in penetration of external light and precise delivery of photosensitizers hamper its clinical translation. As such, the internal light source such as Cerenkov luminescence (CL) from decaying radioisotopes offers new opportunities. Herein, we show that goat milk-derived extracellular vesicles (GEV) can act as a carrier to deliver photosensitizer Chlorin e6 (Ce6) and tumor-avid 18F-FDG can activate CL-induced PDT for precision cancer theranostics. GEV was isolated via differential ultracentrifugation of commercial goat milk and photosensitizer Ce6 was loaded by co-incubation to obtain Ce6@GEV. Tumor uptake of Ce6@GEV was examined using confocal microscopy and flow cytometry. To demonstrate the ability of 18F-FDG to activate photodynamic effects against cancer cells, apoptosis rates were measured using flow cytometry, and the production of 1O2 was measured by reactive oxygen species (ROS) monitoring kit. Moreover, we used the IVIS device to detect Cherenkov radiation and Cerenkov radiation energy transfer (CRET). For animal experiments, a small-animal IVIS imaging system was used to visualize the accumulation of the GEV drug delivery system in tumors. PET/CT and CL images of the tumor site were performed at 0.5, 1, and 2 h. For in vivo antitumor therapy, changes of tumor volume, survival time, and body weight in six groups of tumor-bearing mice were monitored. Furthermore, the blood sample and organs of interest (heart, liver, spleen, lungs, kidneys, and tumor) were collected for hematological analysis, immunohistochemistry, and H&E staining. Confocal microscopy of 4T1 cells incubated with Ce6@GEV for 4 h revealed strong red fluorescence signals in the cytoplasm, which demonstrated that Ce6 loaded in GEV could be efficiently delivered into tumor cells. When Ce6@GEV and 18F-FDG co-existed incubated with 4T1 cells, the cell viability plummeted from more than 88.02 ± 1.30% to 23.79 ± 1.59%, indicating excellent CL-induced PDT effects. In vivo fluorescence images showed a peak tumor/liver ratio of 1.36 ± 0.09 at 24 h after Ce6@GEV injection. For in vivo antitumor therapy, Ce6@GEV + 18F-FDG group had the best tumor inhibition rate (58.02%) compared with the other groups, with the longest survival rate (35 days, 40%). During the whole treatment process, neither blood biochemical analysis nor histological observation revealed vital organ damage, suggesting the biosafety of this treatment strategy. The simultaneous accumulation of 18F-FDG and Ce6 in tumor tissues is expected to overcome the deficiency of traditional PDT. This strategy has the potential to extend PDT to a variety of tumors, including metastases, using targeted radiotracers to provide internal excitation of light-responsive therapeutics. We expect that our method will play a critical role in precision treatment of deep solid tumors.

A traffic light protocol workflow for image-guided adaptive radiotherapy in lung cancer patients.

Image-guided radiotherapy using cone beam-CT (CBCT) images is used to evaluate patient anatomy and positioning before radiotherapy. In this study we analyzed and optimized a traffic light protocol (TLP) used in lung cancer patients to identify patients requiring treatment adaptation. First, CBCT review requests of 243 lung cancer patients were retrospectively analyzed and divided into 6 pre-defined categories. Frequencies and follow-up actions were scored. Based on these results, the TLP was optimized and evaluated in the same way on 230 patients treated in 2018. In the retrospective study, a total of 543 CBCT review requests were created during treatment in 193/243 patients due to changed anatomy of lung (24%), change of tumor volume (24%), review of match (18%), shift of the mediastinum (15%), shift of tumor (15%) and other (4%). The majority of requests (474, 87%) did not require further action. In 6% an adjustment of the match criteria sufficed; in 7% treatment plan adaptation was required. Plan adaptation was frequently seen in the categories changed anatomy of lung, change of tumor volume and shift of tumor outside the PTV. Shift of mediastinum outside PRV and shift of GTV outside CTV (but inside PTV) never required plan adaptation and were omitted to optimize the TLP, which reduced the CBCT review requests by 23%. The original TLP selected patients that required a treatment adaptation, but with a high false positive rate. The optimized TLP reduced the amount of CBCT review requests, while still correctly identifying patients requiring adaptation.