Tumor Growth Rate Research Articles

Tumor Oxygenation in an Orthotopic Model of Breast Cancer: Impact of Dietary Nitrate Supplementation

Introduction: Breast cancer (BC), the predominant non-melanoma cancer among women, is projected to escalate to more than 3 million new cases and ~1 million fatalities globally by 2040. Chronic and fluctuating low oxygen (O2) conditions within tumors favor malignant growth, decreased responsiveness to therapeutic interventions, and reduced patient survivability. Treatment strategies to combat tumor hypoxia are desperately needed. Dietary nitrate supplementation via beetroot juice (BRJ), which increases nitric oxide (NO) production through the nitrate-nitrite-NO pathway, has been demonstrated to increase skeletal muscle blood flow, improve mitochondrial effciency, and reduce metabolic demands. Specifically, BRJ improves interstitial oxygen pressures (PO2 is) in acidic, low oxygen environments such as that found in the tumor microenvironment. Therefore, we hypothesized that BRJ supplementation would increase PO2 is in BC tumors. Methods: Female Fischer 344 retired breeder rats (6-8 months old) were used in this investigation. Adenocarcinoma cells (MAT B III at 6 x 103) were injected into the mammary duct and tumor growth was monitored over 2 weeks. Once tumors reached ~5 mm in diameter, rats were randomly assigned to consume BRJ (1 mmol/kg/day; BRJ, n=3) or water (CON; n=3) for 5 days. Under pentobarbital anesthesia, tumor PO2 is measurements were obtained using phosphorescence quenching. Results: Tumor growth rate was decreased in BRJ compared to CON rats (0.5 ± 0.1 vs. 1.0 ± 0.1 mm/day; p<0.05). Heart rate and mean arterial pressure were not different between groups (P>0.05). Blood lactate was significantly decreased in BRJ compared to CON rats (0.5 ± 0.1 vs. 1.2 ± 0.1 mmol/L, p<0.05). There was an increase in mean tumor PO2 is in BRJ vs. control rats (6.9 ± 1.3 vs. 3.7 ± 0.47; p<0.05). Conclusions: This study offers promising preliminary insights into the potential of dietary nitrate supplementation as an adjunctive approach to BC treatment to increase tumor PO2 is and reduce tumor growth rate. Future and ongoing studies will increase the sample size, use fluorescent microspheres to measure tumor blood flow, and explore the potential for BRJ and other NO agonists to combat tumor hypoxia and the skeletal muscle dysfunction associated with cancer progression. This research was funded by the following sources: the Johnson Cancer Research Center Innovative Research Award and Sustained Momentum for Investigators with Laboratories Established (SMILE) Grants at Kansas State University, the National Institute on Aging (Grant 1R15AG078060), and Ruth L. Kirschstein National Research Service Awards from the National Heart, Lung, and Blood Institute (Grants 1F31HL167618-01 and 1F31HL170643-01). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Ferric Oxide Nanoparticles Enhance Cytotoxicity and Reduce the Occurrence and Development of Cervical Cancer Metastases

Fe3O4 nanoparticles can be used in diagnostic imaging and therapeutic applications. However, poor solubility limits its use in tumors. In this study, we used ferric oxide and nanoparticles to covalently bind ferric oxide nanoparticles as a strategy for treatment of cervical cancer metastases. We aimed to evaluate their biological effects on cervical cancer metastases in vivo. Confocal microscopy was used to detect transfection efficiency, ferric oxide or ferric oxide nanoparticles were used to intervene cervical cancer cell lines, and flow cytometry explored cell apoptosis. The mouse model of cervical cancer metastasis was further treated with ferric oxide or ferric tetroxide nanoparticles through intraperitoneal injection. The tumor volume was counted and size was measured. Cell proliferation and apoptosis were detected by IHC and Western-blot was used to detect protein expression. Nanoparticles significantly enhanced the cellular uptake of Fe3O4, which inhibited cell proliferation and promoted cell apoptosis. In the in vivo transplanted tumor model, the same was observed in mice. In the mice model, ferric oxide nanoparticles significantly inhibited the growth of tumors, slowed down tumor growth rate, and accelerated apoptosis. Our research results showed that nanoparticles contributed to the uptake of oxidized particles, and Fe3O4 nanoparticles regulated studied tumors by enhancing cytotoxicity, thereby inhibiting cell proliferation and promoting cell apoptosis, achieving Fe3O4 nanoparticles. The particles significantly inhibited tumor growth, slowed down multiplication rate, and accelerated apoptosis, suggesting that Fe3O4 nanoparticles have a significant inhibitory effect on cervical cancer transplanted tumors.

Clinicopathological characteristics of secondary trigeminal neuralgia due to cerebellopontine angle tumors.

Cerebellopontine angle (CPA) tumors are a common cause of secondary trigeminal neuralgia (TN), characterized by their concealed location, slow progression, and difficulty in early detection. This study aims to explore the clinicopathological characteristics of patients with secondary TN due to CPA tumors to enhance understanding and management of secondary TN. A retrospective analysis was conducted on clinical data and pathological results of 116 patients with CPA tumor-related TN treated at Xiangya Hospital of Central South University from January 1, 2017 to December 31, 2022. The study analyzed the relationship of tumor pathological types with clinical manifestations, tumor location, surgical methods, and treatment outcomes. Among the cases, 95.7% (111/116) were benign tumors, 3.4% (4/116) were malignant tumors, and 0.9% (1/116) were borderline tumors. Benign tumors were predominantly acoustic neuromas, meningiomas, and schwannomas. Among the patients, 46.6% (54/116) presented with isolated TN, while 53.4% (62/116) exhibited other associated symptoms depending on factors such as tumor growth location and rate. The complete resection rate in this group was over 90%, with 41.4% (48/116) of patients undergoing concurrent microvascular decompression after tumor resection, predominantly for schwannomas. The overall effective rate of surgical treatment reached 93.9%, with schwannomas showing higher efficacy rates compared with acoustic neuromas and meningiomas (P<0.05). The recurrence rate of acoustic neuromas was significantly higher than that of meningiomas and schwannomas (P<0.05). CPA tumors are a major cause of secondary TN, predominantly benign, with occasional underdiagnosed malignant tumors. Early diagnosis and treatment significantly impact prognosis. Different tumor types vary in clinical symptoms, surgical approaches, and treatment efficacy. Surgical strategies should balance tumor resection extent and neural function preservation, with microvascular decompression as necessary.

Anti-Netrin-1 decorated nanoparticles combined with chemotherapy for the treatment of triple-negative breast cancer

Nanoparticle's success as drug delivery systems for cancer treatment has been achieved through passive targeting mechanisms. However, tumor heterogeneity and rapid drug clearance limit the treatment efficacy. Improved outcomes and selective drug release can be achieved by grafting ligands at the surface of nanocarriers that bind molecules overexpressed in the tumor microenvironment (TME). In this work, we developed a docetaxel-loaded nanoemulsions (NEs) binding an anti-netrin-1 monoclonal antibody (NP137) to selectively target the netrin-1 protein overexpressed in many different tumors. The goal is to refine a combined approach utilizing NP137 and docetaxel as an improved tumor-targeting chemotherapeutic agent for addressing triple-negative breast cancer (TNBC). Several factors have been considered for the optimization of the active targeted drug delivery system via the click-chemistry conjugation, as the impact of PEGylated surfactant that stabilize the NEs shell on conjugation efficiency, cytocompatibility with EMT6 cell line and colloidal stability over time of NEs. Results showed that a 660 Da PEG chain length contributed to NEs colloidal stability and had no impact on cell viability or on the antibody binding ability for its ligand after surface conjugation. Moreover, docetaxel was encapsulated into the oily core of NEs, with an encapsulation efficiency of 70 %. To validate our treatment strategy in vivo, the 4T1 murine breast cancer model was used. As a result, the comparison of active-targeted and non-targeted NEs revealed that only active-targeted NE could decrease the tumor growth rate.

20-hydroxyecdysone suppresses bladder cancer progression via inhibiting USP21: A mechanism associated with deubiquitination and degradation of p65

Bladder cancer is one of the most common malignancies of the urinary tract and a prevalent cancer worldwide, still requiring efficient therapeutic agents and approaches. 20-Hydroxyecdysone (20-HE), a steroid hormone, can be found in insects and few plants and mediate numerous biological events to control the progression of varying diseases; however, its impacts on bladder cancer remain unclear. In the study, we found that 20-HE treatments effectively inhibited the viability and proliferation of bladder cancer cells and induced apoptosis by activating Caspase-3. The migratory and invasive potential of bladder cancer cells was markedly repressed by 20-HE in a dose-dependent manner. The inhibitory effects of 20-HE on bladder cancer were confirmed in an established xenograft mouse model, as indicated by the markedly reduced tumor growth rates and limited lung and lymph node metastasis. High-throughput RNA sequencing was performed to explore dysregulated genes in bladder cancer cells after 20-HE treatment. We identified ubiquitin-specific protease 21 (USP21) as a key deubiquitinating enzyme for bladder cancer progression and a positive correlation between USP21 and nuclear factor-κB (NF-κB)/p65 in patients. Furthermore, 20-HE treatments markedly reduced USP21 expression, NF-κB/p65 mRNA, stability and phosphorylated NF-κB/p65 expression levels in bladder cancer cells, which were validated in animal tumor tissues. Mechanistic studies showed that USP21 directly interacted with and stabilized p65 by deubiquitinating its K48-linked polyubiquitination in bladder cancer cells, which could be abolished by 20-HE treatment, contributing to p65 degradation. Finally, we found that USP21 overexpression could not only facilitate the proliferation, migration, and invasion of bladder cancer cells, but also significantly eliminated the suppressive effects of 20-HE on bladder cancer. Notably, 20-HE could still perform its anti-tumor role in bladder cancer when USP21 was knocked down with decreased NF-κB/p65 expression and activation, revealing that USP21 suppression might not be the only way for 20-HE during bladder cancer treatment. Collectively, all our results clearly demonstrated that 20-HE may function as a promising therapeutic strategy for bladder cancer treatment mainly through reducing USP21/p65 signaling expression.

Predictive significance of FGFR4 p.G388R polymorphism in metastatic colorectal cancer patients receiving trifluridine/tipiracil (TAS-102) treatment

BackgroundTAS-102 (Lonsurf®) is an oral fluoropyrimidine consisting of a combination of trifluridine (a thymidine analog) and tipiracil (a thymidine phosphorylation inhibitor). The drug is effective in metastatic colorectal cancer (mCRC) patients refractory to fluorouracil, irinotecan and oxaliplatin. This study is a real-world analysis, investigating the interplay of genotype/phenotype in relation to TAS-102 sensitivity.MethodsForty-seven consecutive mCRC patients were treated with TAS-102 at the National Cancer Institute of Naples from March 2019 to March 2021, at a dosage of 35 mg/m2, twice a day, in cycles of 28 days (from day 1 to 5 and from day 8 to 12). Clinical-pathological parameters were described. Activity was evaluated with RECIST criteria (v1.1) and toxicity with NCI-CTC (v5.0). Survival was depicted through the Kaplan-Meyer curves. Genetic features of patients were evaluated with Next Generation Sequencing (NGS) through the Illumina NovaSeq 6000 platform and TruSigt™Oncology 500 kit.ResultsMedian age of patients was 65 years (range: 46–77). Forty-one patients had 2 or more metastatic sites and 38 patients underwent to more than 2 previous lines of therapies. ECOG (Eastern Cooperative Oncology Group) Performance Status (PS) was 2 in 19 patients. The median number of TAS-102 cycles was 4 (range: 2–12). The most frequent toxic event was neutropenia (G3/G4 in 16 patients). There were no severe (> 3) non-haematological toxicities or treatment-related deaths. Twenty-six patients experienced progressive disease (PD), 21 stable disease (SD). Three patients with long-lasting disease control (DC: complete, partial responses or stable disease) shared an FGFR4 (p.Gly388Arg) mutation. Patients experiencing DC had more frequently a low tumour growth rate (P = 0.0306) and an FGFR4 p.G388R variant (P < 0.0001). The FGFR4 Arg388 genotype was associated with better survival (median: 6.4 months) compared to the Gly388 genotype (median: 4 months); the HR was 0.25 (95% CI 0.12- 0.51; P = 0.0001 at Log-Rank test).ConclusionsThis phenotype/genotype investigation suggests that the FGFR4 p.G388R variant may serve as a new marker for identifying patients who are responsive to TAS-102. A mechanistic hypothesis is proposed to interpret these findings.Graphical

Deferral of Treatment for Small Choroidal Melanoma and the Risk of Metastasis: An Investigation Using the Liverpool Uveal Melanoma Prognosticator Online (LUMPO).

We estimated metastatic-death risk when the treatment of small choroidal melanomas is deferred until growth is observed. In 24 patients with choroidal melanoma (median diameter 5.85 mm), the exponential growth rate estimated by a mixed-effects model was 4.3% per year. Using the Liverpool Uveal Melanoma Prognosticator Online v.3 (LUMPO3), we measured changes in 15-year metastatic and non-metastatic death risks according to whether the tumor is treated immediately or after observing growth 4 or 12 months later, considering age, sex, and metastasis predictors. In 40-year-old females with 10 mm, disomy 3 and monosomy 3 choroidal melanomas (prevalence 16%), the 15-year absolute risks of metastatic death are 4.2% and 76.6%, respectively, increasing after a 4-month delay by 0.0% and 0.2% and by 3.0% and 2.3% with tumor growth rates of 5.0% and 20.0%, respectively. With 12-month delays, these risks increase by 0.0% and 0.5% and by 1.0% and 7.1%, respectively. Increases in metastatic-death risk are less with smaller tumors and with a higher risk of non-metastatic death. Deferring treatment of choroidal melanomas until documentation of growth may delay iatrogenic visual loss by months or years and is associated with minimal increase in metastatic mortality, at least with small tumors with usual growth rates of up to 40% per year.

Quantitative Assessment of Drug Efficacy and Emergence of Resistance in Patients with Metastatic Renal Cell Carcinoma Using a Longitudinal Exposure-Tumor Growth Inhibition Model: Apitolisib (Dual PI3K/mTORC1/2 Inhibitor) Versus Everolimus (mTORC1 Inhibitor).

Cancer remains a significant global health challenge, and despite remarkable advancements in therapeutic strategies, poor tolerability of drugs (causing dose reduction/interruptions) and/or the emergence of drug resistance are major obstacles to successful treatment outcomes. Metastatic renal cell carcinoma (mRCC) accounts for 2% of global cancer diagnoses and deaths. Despite the initial success of targeted therapies in mRCC, challenges remain to overcome drug resistance that limits the long-term efficacy of these treatments. Our analysis aim was to develop a semi-mechanistic longitudinal exposure-tumor growth inhibition model for patients with mRCC to characterize and compare everolimus (mTORC1) and apitolisib's (dual PI3K/mTORC1/2) ability to inhibit tumor growth, and quantitate each drug's efficacy decay caused by emergence of tumor resistance over time. Model-estimated on-treatment tumor growth rate constant was 1.7-fold higher for apitolisib compared to everolimus. Estimated half-life for loss of treatment effect over time for everolimus was 16.1 weeks compared to 7.72 weeks for apitolisib, suggesting a faster rate of tumor re-growth for apitolisib patients likely due to the emergence of resistance. Goodness-of-fit plots including visual predictive check indicated a good model fit and the model was able to capture individual tumor size-time profiles. Based on our knowledge, this is the first clinical report to quantitatively assess everolimus (mTORC1) and apitolisib (PI3K/mTORC1/2) efficacy decay in patients with mRCC. These results highlight the difference in overall efficacy of 2 drugs due to the quantified efficacy decay caused by emergence of resistance, and emphasize the importance of model-informed drug development for targeted cancer therapy.

A new perspective on prostate cancer treatment: the interplay between cellular senescence and treatment resistance.

The emergence of resistance to prostate cancer (PCa) treatment, particularly to androgen deprivation therapy (ADT), has posed a significant challenge in the field of PCa management. Among the therapeutic options for PCa, radiotherapy, chemotherapy, and hormone therapy are commonly used modalities. However, these therapeutic approaches, while inducing apoptosis in tumor cells, may also trigger stress-induced premature senescence (SIPS). Cellular senescence, an entropy-driven transition from an ordered to a disordered state, ultimately leading to cell growth arrest, exhibits a dual role in PCa treatment. On one hand, senescent tumor cells may withdraw from the cell cycle, thereby reducing tumor growth rate and exerting a positive effect on treatment. On the other hand, senescent tumor cells may secrete a plethora of cytokines, growth factors and proteases that can affect neighboring tumor cells, thereby exerting a negative impact on treatment. This review explores how radiotherapy, chemotherapy, and hormone therapy trigger SIPS and the nuanced impact of senescent tumor cells on PCa treatment. Additionally, we aim to identify novel therapeutic strategies to overcome resistance in PCa treatment, thereby enhancing patient outcomes.

Hierarchical cluster analysis and nonlinear mixed-effects modelling for candidate biomarker detection in preclinical models of cancer.

BackgroundPreclinical models of cancer can be of translational benefit when assessing how different biomarkers are regulated in response to particular treatments. Detection of molecular biomarkers in preclinical models of cancer is difficult due inter-animal variability in responses, combined with limited accessibility of longitudinal data. MethodsNonlinear mixed-effects modelling (NLME) was used to analyse tumour growth data based on expected tumour growth rates observed 7 days after initial doses (DD7) of Radiotherapy (RT) and Combination of RT with DNA Damage Response Inhibitors (DDRi). Cox regression was performed to confirm an association between DD7 and survival. Hierarchical Cluster Analysis (HCA) was then used to identify candidate biomarkers impacting responses to RT and RT/DDRi and these were validated using NLME. ResultsCox regression confirmed significant associations between DD7 and survival. HCA of RT treated samples, combined with NLME confirmed significant associations between DD7 and Cluster specific CD8+ Ki67 MFI, as well as DD7 and cluster specific Natural Killer cell density in RT treated mice. ConclusionApplication of NLME, as well as HCA of candidate biomarkers may provide additional avenues to assess the effect of RT in MC38 syngeneic tumour models. Additional studies would need to be conducted to confirm association between DD7 and biomarkers in RT/DDRi treated mice.

Anti-tumor effect of high doses of carbon ions and x-rays during irradiation of Ehrlich ascites carcinoma cells ex vivo

The effect of carbon ions (12C) with the energy of 400 MeV/nucleon on the dynamics of induction and growth rate of solid tumors in mice under irradiation of Ehrlich’s ascites carcinoma cells (EAC) ex vivo at doses of 5–30 Gy relative to the action of equally effective doses of X-ray radiation was studied. The dynamics of tumor induction under the action of 12C and X-rays had a similar character and depended on the dose during 3 months of observation. The value of the latent period, both when irradiating cells with 12C and X-ray, increased with increasing dose, and the interval for tumor induction decreased. The rate of tumor growth after ex vivo irradiation of EAC cells was independent of either dose or type of radiation. The dose at which EAC tumors are not induced within 90 days was 30 Gy for carbon ions and 60 Gy for X-rays. The value of the relative biological effectiveness of carbon ions, calculated from an equally effective dose of 50% probability of tumors, was 2.59.

Tumors Established in a Defective Immune Environment Reprogram the Oncogenic Signaling Pathways to Escalate Tumor Antigenicity.

Tumors developed in immunocompromised hosts are more immunogenic. However, few studies have addressed the potential mechanisms underlying the high immunogenicity of tumors found in a suppressed immune system. Therefore, we aimed to elucidate the impacts of the immune system on tumor behaviors and immunogenicity sculpting. A murine colorectal adenocarcinoma cell line, CT26wt, was administrated into immunocompetent (BALB/c) and immunocompromised (NOD.SCID) mice, respectively. On day 11, the CT26 cells slowly progressed in the NOD.SCID mice compared to the BALB/c mice. We then performed liquid chromatography-tandem mass spectrometry (LC-MS/MS) and analyzed the differentially expressed proteins (DEPs). The DEPs participated in numerous oncogenic pathways, PI3K/AKT/mTOR cell signaling, and the silencing of several tumor suppressors, such as PTEN and RBL1, during tumorigenesis. On day 34, the CT26/SCID tumors inversely became malignant counterparts; then the CT26/SCID tumors were harvested and re-inoculated into immunocompetent mice (CT26/SCID-Re tumors) to determine the immunogenicity. The CT26/SCID-Re tumor growth rate significantly decreased. Furthermore, increased infiltrations of dendritic cells and tumor-infiltrating T lymphocytes were found in the CT26/SCID-Re tumors. These findings suggest that immunogenic tumors might express multiple tumor rejection antigens, unlike wild-type tumors, and attract more immune cells, therefore decreasing the growth rate. Collectively, our study first revealed that in immunodeficient hosts, tumor suppressors were silenced and oncogenic signaling pathways were changed during the initial phase of tumor development. With tumor progression, the tumor antigens were overexpressed, exhibiting elevated immunogenicity. This study offers a hint on the mechanisms of tumorigenesis and provides a niche for investigating the interaction between host immunity and cancer development.

Abstract CT257: Hyperprogressive disease following bintrafusp alfa and DNA damaging chemotherapy in relapsed small cell lung cancer

Abstract Background: Small cell lung cancer (SCLC) is the most aggressive type of lung cancer. Current therapies have limited efficacy in SCLC, and despite a highly mutated genome, SCLC is largely unresponsive to immunotherapy. We sought to leverage the immune surveillance triggered by DNA damage in patients with relapsed SCLC using bintrafusp alfa, a bifunctional fusion protein targeting both PD-L1 and TGF-beta. Hyperprogressive disease (HPD), characterized by the rapid acceleration of tumor growth, has been reported in approximately 13% of patients treated with immune checkpoint inhibitors. However, the mechanistic basis is poorly understood. Methods: This is a safety run-in and phase II clinical trial. Cohort 1 enrolled patients with relapsed SCLC across Arms A (bintrafusp alfa 2400 mg q3 wks), B (bintrafusp alfa 2400 mg on D1 plus topotecan 1 mg/m2/day on D1-5 q3 wks), and C (bintrafusp alfa 1200 mg on D1 q2 wks plus temozolomide 200 mg/m2/day on D1-5 q4 wks). The primary endpoint was objective response rate (ORR). Results: Thirty-seven patients enrolled. Grade 3 treatment-related adverse events (TRAE) included transaminitis (27.0%), anemia (24.4%), lymphopenia (10.8%), and maculopapular rash (5.4%). Grade 4 TRAE included thrombocytopenia (8.1%), lymphopenia (5.4%) and transaminitis (5.4%). One patient experienced grade 5 tumor hemorrhage. By RECIST 1.1, partial responses were observed in 5 (13.5%), stable disease in 11 (29.7%), and progressive disease in 21 (56.8%) patients. Importantly, 13 (35.1%) patients developed HPD (≥ 2x increase in tumor growth rate from pre-trial vs on-trial, time to treatment failure ≤ 2 months, and ≥ 50% increase tumor burden). Changes in circulating cell-free DNA (n=20) tumor fraction using DELFI-TF, a mutation-independent, low-coverage whole genome sequencing approach, correlated with treatment responses. Pre-treatment serum from HPD (n=10 vs. 9 non-HPD) patients showed significantly lower levels of inflammatory cytokines (CXCL10, CCL13, CCL8, CCL19, TRAIL) and Granzyme H, and higher levels of anti-inflammatory cytokine IL10. Consistently, pre-treatment tumor transcriptomes of HPD (n=5 vs. 7 non-HPD) patients revealed suppression of IFN-gamma response, allograft rejection, and inflammatory response pathways. Conclusions: Concomitant TGF-beta and PD-L1 blockade is associated with a high frequency of HPD in SCLC patients. cfDNA could be critical for monitoring HPD. Tumor and blood immune signatures may inform the likelihood of HPD, with immune excluded tumors more likely to develop HPD. NCT Number: NCT03554473 Bintrafusp alfa was provided by EMD Serono (CrossRef Funder ID: 10.13039/100004755) Citation Format: Brett Schroeder, Nobuyuki Takahashi, Howard Yang, Renee Donahue, Zachary Skidmore, Alissa Konicki, Michael Nirula, Max Greenberg, George Chrisafis, Yang Zhang, Yo-Ting Tsai, Linda Sciuto, Samantha Nichols, Melissa Abel, Parth Desai, Rajesh Kumar, Christopher Schultz, Danielle Pinkiert, Chante Graham, Ajit Sharma, Justin Malin, Manan Krishnamurthy, Sophie Zhuang, Maxwell Lee, Lorenzo Rinaldi, Jeffrey Schlom, Lalage Wakefield, Anish Thomas. Hyperprogressive disease following bintrafusp alfa and DNA damaging chemotherapy in relapsed small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT257.

Abstract LB279: The combination therapy with B7-H3 antibody drug conjugates for effective radiation treatment

Abstract Purpose: Antibody-drug conjugate (ADC) is a promising treatment modality because it enables effective tumor-specific delivery of anticancer drugs by targeting cancer antigens with antibodies. By using ADC, each treatment can be used at an optimal dose, thereby minimizing side effects, and maximizing treatment effects. The ADC used in this experiment targets B7-H3, and the B7-H3 protein is highly expressed in various cancer types. Recent studies have shown that B7-H3 is increased by radiation in various cancer cells. This study aims to demonstrate the efficacy of the B7-H3 ADC and confirm its combined effect with radiotherapy. Method: In vitro, colony forming assay, CCK-8 assay, FACs and western blotting were performed in JIMT-1 and HCT116 cell lines. In vivo, JIMT-1, HCT116 and Colon PDX models were developed to monitor tumor growth and survival rate. Biodistribution was performed through the IVIS (In Vivo Imaging System) spectrum. Result: The B7-H3 ADC used in the experiment was developed by combining DUBA as a toxin with anti-B7-H3 antibody In in vitro experiments, the combined treatment of radiation and B7-H3 ADC reduced cell viability via apoptosis more effectively than treatment alone. In the in vivo mouse models, we observed that the combined treatment of radiation and B7-H3 ADC was more effective in inhibiting tumor growth than the single treatment groups. The survival rate of the mice was also improved when the radiation was combined with B7-H3 ADC treatment compared to the other treatment groups alone. In the biodistribution results, the accumulation of B7-H3 ADC-Cy7 was further enhanced when irradiated. Conclusion: The results show that B7-H3 ADC can be used as a promising therapeutic agent and the combined treatment with radiation can obtain an improved anticancer effect than the single treatment, suggesting another cancer treatment method. Citation Format: Gawon Son, Eunjin Ju, Jin Park, Seolhwa Shin, Eunjeong Ko, Miri Kwon, Hyewon Lee, Beomseok Seo, Sangkwang Lee, Seoksoon Park, Seongyun Jeong, Siyeol Song, Eunkyung Choi. The combination therapy with B7-H3 antibody drug conjugates for effective radiation treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB279.

IRX4204 Induces Senescence and Cell Death in HER2-positive Breast Cancer and Synergizes with Anti-HER2 Therapy.

Rexinoids, agonists of nuclear retinoid X receptor (RXR), have been used for the treatment of cancers and are well tolerated in both animals and humans. However, the usefulness of rexinoids in treatment of breast cancer remains unknown. This study examines the efficacy of IRX4204, a highly specific rexinoid, in breast cancer cell lines and preclinical models to identify a biomarker for response and potential mechanism of action. IRX4204 effects on breast cancer cell growth and viability were determined using cell lines, syngeneic mouse models, and primary patient-derived xenograft (PDX) tumors. In vitro assays of cell cycle, apoptosis, senescence, and lipid metabolism were used to uncover a potential mechanism of action. Standard anti-HER2 therapies were screened in combination with IRX4204 on a panel of breast cancer cell lines to determine drug synergy. IRX4204 significantly inhibits the growth of HER2-positive breast cancer cell lines, including trastuzumab and lapatinib-resistant JIMT-1 and HCC1954. Treatment with IRX4204 reduced tumor growth rate in the MMTV-ErbB2 mouse and HER2-positive PDX model by 49% and 44%, respectively. Mechanistic studies revealed IRX4204 modulates lipid metabolism and induces senescence of HER2-positive cells. In addition, IRX4204 demonstrates additivity and synergy with HER2-targeted mAbs, tyrosine kinase inhibitors, and antibody-drug conjugates. These findings identify HER2 as a biomarker for IRX4204 treatment response and demonstrate a novel use of RXR agonists to synergize with current anti-HER2 therapies. Furthermore, our results suggest that RXR agonists can be useful for the treatment of anti-HER2 resistant and metastatic HER2-positive breast cancer.

Abstract LB376: Tirzepatide inhibits tumor growth in mice with diet-induced obesity

Abstract Tirzepatide, a drug used in management of type II diabetes, is an activator of both glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) receptors. Tirzepatide treatment leads to weight loss in murine models of obesity, and clinical trials have shown the drug can achieve ∼ 20% weight loss in obese patients. Obesity has been shown to increase risk and/or to worsen prognosis of certain common cancers, including colon cancer, but the effect of tirzepatide on neoplasia has not been examined in detail. We studied the effects of this drug on mouse weight and energy balance and on the murine MC38 colon cancer model, which was previously shown to exhibit accelerated growth in hosts with diet-induced obesity. Tirzepatide led to substantial reductions in food intake, to reduced adipose tissue mass, and to significant decreases in circulating levels of insulin and leptin. Tirzepatide did not cause tumor regression, but reduced tumor growth rates by ∼ 50%. Tirzepatide had no effect on MC38 cancer cell proliferation in vitro, and the effect of tirzepatide on tumor growth in vivo could be phenocopied in placebo treated mice simply by restricting food intake to the amount consumed mice receiving the drug. This provides evidence that the drug acts indirectly to inhibit tumor growth. Our findings raise the possibility that use of tirzepatide or similar agents may benefit patients with obesity-related cancers. Citation Format: Michael N. Pollak, Jibin Zeng, Linxuan Huang, Ye Wang, Janane Rahbani, Lawrence Kazak. Tirzepatide inhibits tumor growth in mice with diet-induced obesity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB376.

Analysis of the effect of CCR7 on the microenvironment of mouse oral squamous cell carcinoma by single-cell RNA sequencing technology

BackgroundStudies have shown that CCR7, an important inflammatory factor, can promote the proliferation and metastasis of oral squamous cell carcinoma (OSCC), but its role in the tumor microenvironment (TME) remains unclear. This paper explores the role of CCR7 in the TME of OSCC.MethodsIn this work, we constructed CCR7 gene knockout mice and OSCC mouse models. Single-cell RNA sequencing (scRNA-seq) and bioinformatics were used to analyze the differences in the OSCC microenvironment between three CCR7 gene knockout mice (KO) and three wild-type mice (WT). Immunohistochemistry, immunofluorescence staining, and flow cytometry were used to analyze the expression of key genes in significantly different cell types between the KO and WT groups. An in vitro experiment was used to verify the effect of CCR7 on M2 macrophage polarization.ResultsIn the mouse OSCC models, the tumor growth rate in the KO group was significantly lower than that in the WT group. Eight main cell types (including tumor cells, fibroblasts, macrophages, granulocytes, T cells, endothelial cells, monocytes, and B cells) were identified by Seurat analysis. The scRNA-seq results showed that the proportion of tumor cells was lower, but the proportion of inflammatory cells was significantly higher in the KO group than in the WT group. CellPhoneDB analysis results indicated a strong interaction relationship between tumor cells and macrophages, T cells, fibroblasts, and endothelial cells. Functional enrichment results indicated that the expression level of the Dusp1 gene in the KO group was generally higher than that in the WT group in various cell types. Macrophage subclustering results indicated that the proportion of M2 macrophages in the KO group was lower than that in the WT group. In vitro experimental results showed that CCR7 can promote M2 macrophage polarization, thus promoting the proliferation, invasion and migration of OSCC cells.ConclusionsCCR7 gene knockout can significantly inhibit the growth of mouse oral squamous cell carcinoma by promoting the polarization of M2 macrophages.

Abstract 478: Targeted combination nano-drug delivery system to enhance anti-cancer efficacy and reduce side effects

Abstract Background: Colorectal cancer (CRC) is a global health concern, with significant morbidity and mortality. Oxaliplatin (OXL) is a common treatment for CRC but its effectiveness is hampered by side effects, including gastrointestinal and neurotoxic effects. APX3330 exerts anti-angiogenic and neuroprotective effects. It is proposed that the combined use of OXL and APX3330-loaded nanoparticles (NPs) would improve drug delivery to cancer cells with enhanced therapeutic efficacy while reducing side effects of OXL. Methods: We developed dual-loaded NPs containing OXL and APX3330 linked to a cancer targeting monoclonal antibody (NPs+mAb). We characterized the physicochemical properties of the NPs and evaluated their cytotoxicity and drug release using CRC cell lines. In vivo, we assessed their therapeutic efficiency and side effects using an orthotopic CRC mouse model. Results: NPs exhibited an average size of 229±26 nm with a zeta potential of -24.1±2.1 mV. The drug loading and encapsulation efficiency were 3.3±0.2% and 71.9%, respectively. Morphological analysis via scanning electron microscopy confirmed NP structure. In vitro drug release studies showed a slower release profile from NPs compared to free OXL, with a cumulative release of 34% (w/w) after 48 hours. Notably, cytotoxicity evaluation on CT-26 cells revealed a significant reduction in the IC50 for NPs compared to free APX3330 and OXL. In vivo studies demonstrated a remarkable 31% reduction in tumor growth rate in animals treated with NPs+mAb compared to those receiving free forms of OXL and APX3330. Body weight for animals treated with NPs+mAb remained similar to the healthy group, indicating minimal systemic toxicity. Moreover, the length of the colon in healthy organs remained steady compared to animals treated with OXL, which experienced a reduction in colon length. Animals treated with the free form of OXL exhibited diarrhoea, while the stool water content for animals treated with NPs+mAb remained at a similar level as the healthy group, suggesting reduced gastrointestinal side effects. Conclusions: This study demonstrates the potential of NPs with improved retention and encapsulation efficiency for effective drug delivery. Our research validates our novel method for creating NPs with mAb conjugation, enhancing cytotoxicity against CRC cell lines. In conclusion, the designed NPs+mAb formulation improves OXL treatment efficacy, providing targeted delivery of anti-cancer drugs to the tumor site and reducing tumor size while minimizing side effects. Citation Format: Niloufar Rashidi, Majid Davidson, Vasso Apostolopoulos, Mark R. Kelley, Kulmira Nurgali. Targeted combination nano-drug delivery system to enhance anti-cancer efficacy and reduce side effects [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 478.

Abstract 2286: Clonal sweep dynamics: A marker of tumor fitness and predictor of clinical outcomes

Abstract Cancer evolution is a complex process driven by cellular adaptations to environmental pressures. Understanding a tumor's evolutionary path is crucial for tailoring therapeutic strategies based on its genomic profile. We developed a method that estimates tumor 'fitness' (w) by analyzing the time of every clonal sweep. This is quantified by driver copy number or point mutations through analytical solutions derived from the branching process of tumor evolution. The method incorporates tumor size and growth rate, assessed through in-vivo BrdU staining, to determine the tumor's age, diversity, and aggressiveness. Using our method in the Yates et al. 2015 multi-region study, we analyzed 303 breast cancer tumors from 45 patients using whole-genome and exome sequencing (WES), focusing on ER+ (N=26) and ER- (N=19) subtypes. A negative correlation was observed between clonal cytoband alterations and fitness (ER+, R=-0.41; P=0.04; ER-, R=-0.72; P&amp;lt;0.001). Expanding the analysis with the METABRIC study (Curtis et al. 2012), clonal cytoband alterations (CA) were linked to survival outcomes for both ER+ and ER- subtypes. Additionally, in the TRACERx NSCLC study (Jamal-Hanjani et al. 2017) of 327 tumors from 100 patients who underwent WES, the median tumor fitness was associated with a higher risk of recurrence or death. Survival analyses are detailed in Table 1 below. Multivariate analysis was adjusted for tumor size, nodal status, and CD8α expression in the breast cancer study, and according to the authors' methodology in the TRACERx study, respectively. The observed tumor growth rates in both studies align with known doubling times, demonstrating our method's accuracy. This approach successfully identifies tumor profiles linked to worse outcomes in breast and NSCLC cancers. Our findings suggest that analyzing clonal composition in tumors can improve patient stratification, particularly in infiltrated tumors, potentially enhancing immunotherapy response due to increased neoantigen exposure. Table 1 Survival Analysis Study and Endpoint Parameter Univariate HR (95% CI) Multivariate HR (95% CI) METABRIC: ER- (N=128) on RFS CA &amp;gt; 3 (Ref: CA ≤ 3) 0.61 (0.40, 0.93), P=0.02 0.49 (0.32, 0.75), P&amp;lt;0.001 METABRIC: ER- (N=128) on OS CA &amp;gt; 3 (Ref: CA ≤ 3) 0.68 (0.47, 1), P=0.05 0.60 (0.4, 0.88), P=0.01 METABRIC: ER+ (N=458) on RFS CA &amp;gt; 3 (Ref: CA ≤ 3) 1.61 (1.33, 1.94), P&amp;lt;0.001 1.51 (1.25, 1.82), P&amp;lt;0.001 METABRIC: ER+ (N=458) on OS CA &amp;gt; 3 (Ref: CA ≤3) 1.44 (1.23, 1.68), P&amp;lt;0.001 1.38 (1.18, 1.61), P&amp;lt;0.001 TRACERx NSCLC (N=43) on RFS Med. w &amp;gt; 1.031 (Ref: w ≤ 1.031) 3.24 (1.38, 7.62),P=0.007 4.11 (1.12, 15.1), P=0.033 Citation Format: Luis E. Lara Gonzalez, Sherene Loi, Anthony T. Papenfuss, David L. Goode. Clonal sweep dynamics: A marker of tumor fitness and predictor of clinical outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2286.

Abstract 4185: Neutralizing human IFN-β combined with anti-human PD-L1 and anti-human CTLA-4 treatment increased control of endometrial tumor growth in a novel HLA-A matched BLT humanized mice

Abstract High concentrations of type I interferon can induce growth arrest and apoptosis in cancer cells upon acute exposure, while low concentrations of the same can provide significant pro-survival benefits upon chronic exposure. In vitro data show the dependence of cancer cells on self-generated IFN-I leads to their demise if the IFN-β gene is disrupted, but they manage to persist when provided with IFN-β from an external source. Importantly, murine models show that inhibition of myeloid-associated INF-β can limit tumor growth. As blockage of type I interferon can also restore the CD8+ T cell function after chronic viral infection, we sought to determine the effects of neutralizing anti-human IFN-β antibody 7859 (N-anti-IFN-β) when added to T-cell directed immunotherapy in BLT humanized mice implanted with HLA-A matched human endometrial cancer PDX specimens. Specifically, we tested the combination of immunotherapy with N-anti-IFN-β combined with anti-human PD-L1 and anti-human CTLA-4. N-anti-IFN-β was first characterized for neutralizing activity to confirm specific neutralization of IFNβ and not human IFN-β. HLA-A matched genotyped CD34 stem cells and thymus (BLT humanized mice) and clinical endometrial tumors (PDX) were joined in BLT humanized mice before infusions with N-anti-IFN-β with or without anti-human PD-L1 and anti-human CTLA-4, anti-human PD-L1 and anti-human CTLA-4 alone, and IgG control antibodies intraperitoneally twice per week over three weeks. Tumor sizes were measured weekly and weighted at the end of the study. Human leukocytes infiltrating PDX were assessed by IHC and flow cytometry. Leukocyte subset activation, exhaustion, and tumor-specific T-cell function were measured. Anti-human PD-L1 and anti-human CTLA-4 reduced tumor growth by 82.9% (p&amp;lt;0.0001), but quickly increased the T cell exhaustion markers PD-1 and LAG3. The addition of N-anti-IFN-β to immunotherapy significantly decreased the tumor growth rate by 96.2% (p&amp;lt;0.0001) also significantly different from immunotherapy alone (p=0.0009) N-anti-IFN-β monotherapy reduced tumor growth rate by 42.4% (p=0.0032). While there was an increase in infiltrating CD4 and CD8 T-cells in combination therapy, reductions in expression of PD-1 and LAG3 were observed when compared to immunotherapy or N-IFN-β groups alone Analysis was done with Prism software. The use of a novel HLA-A matched BLT humanized mice with human tumor PDX model shows that neutralization of IFN-β can increase the T-cell anti-tumor activity and tumor repression of immunotherapy with anti-human PD-L1 and anti-human CTLA-4 treatment. Citation Format: Zhe Yuan, Guorui Zu, Xiao Sun, Emmanouil Papasavvas, Lily Lu, Joel Cassel, Peter L. Lutes, Mark Cadungog, Joseph Salvino, Luis J. Montaner. Neutralizing human IFN-β combined with anti-human PD-L1 and anti-human CTLA-4 treatment increased control of endometrial tumor growth in a novel HLA-A matched BLT humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4185.