Search Results (452)

Elevated extracellular potassium (K⁺) in the tumor microenvironment (TME) of breast and other cancers is increasingly recognized as a critical factor influencing tumor progression and immune suppression. Current methods for noninvasive mapping of the potassium distribution in tumors are limited. Here, we employed photoacoustic chemical imaging (PACI) with a solvatochromic dye-based, potassium-sensitive nanoprobe (SDKNP) to quantitatively visualize extracellular potassium levels in an orthotopic metaplastic breast cancer mouse model, Ccn6-KO. Tumors of three distinct sizes (5 mm, 10 mm, and 20 mm) were imaged using multi-wavelength photoacoustic imaging at five laser wavelengths (560, 576, 584, 605, and 625 nm). Potassium concentration maps derived from spectral unmixing of the photoacoustic images at the five laser wavelengths revealed significantly increased potassium levels in larger tumors, confirmed independently by inductively coupled plasma mass spectrometry (ICP-MS). The PACI results matched ICP-MS measurements, validating PACI as a robust, noninvasive imaging modality for potassium mapping in tumors in vivo. This work establishes PACI as a promising tool for studying the chemical properties of the TME and provides a foundation for future studies evaluating the immunotherapy response through ionic biomarker imaging. Full article

Breast cancer (BC) is the most common malignancy and the second-leading cause of cancer-related mortalities in women. Epidemiological studies suggested the reduced BC incidence in Mediterranean populations due to the daily consumption of diets rich in extra-virgin olive oil (EVOO). EVOO secoiridoid phenolics are widely known for their positive outcomes on multiple cancers, including BC. The current study investigates the suppressive effects of individual and combined EVOO phenolics for BC progression and motility. Screening of a small library of EVOO phenolics at a single dose of 10 µM against the viability of the BC cell lines ZR-75-1 (luminal A) and MDA-MB-231 (triple negative BC, TNBC) identified oleocanthal (OC) and ligstroside aglycone (LA) as the most active hits. Screening of EVOO phenolics for BC cells migration inhibition identified OC, LA, and the EVOO lignans acetoxypinoresinol and pinoresinol as the most active hits. Combination studies of different olive phenolics showed that OC combined with LA had the best synergistic inhibitory effects against the TNBC MDA-MB-231 cells migration. A combination of 5 µM of each of OC and LA potently suppressed the migration and invasion of the MDA-MB-231 cells versus LA and OC individual therapies and vehicle control (VC). Animal studies using the ZR-75-1 BC cells orthotopic xenografting model in female nude mice showed significant tumor progression suppression by the combined OC-LA, 5 mg/kg each, ip, 3X/week treatments compared to individual LA and OC treatments and VC. The BC suppressive effects of the OC-LA combination were associated with the modulation of SMYD2–EZH2–STAT3 signaling pathway. A metastasis–clonogenicity animal study model using female nude mice subjected to tail vein injection of MDA-MB-231-Luc TNBC cells also revealed the effective synergy of the combined OC-LA, 5 mg/kg each, compared to their individual therapies and VC. Thus, EVOO cultivars rich in OC with optimal LA content can be useful nutraceuticals for invasive hormone-dependent BC and TNBC progression and metastasis. Full article

The application of personalized medicine to lung adenocarcinoma has resulted in new therapies based on specific oncogenic drivers that have improved patient outcomes. However, oncogene-defined subsets of patients exhibit a significant heterogeneity of response to these agents. Defining the factors that mediate the varied depth and duration of response are critical to developing new therapeutic strategies. While the examination of patient samples can provide important correlations, definitive mechanistic studies require the use of relevant preclinical models. Based on a large body of data, interactions between cancer cells and the surrounding tumor microenvironment, comprised of inflammatory, immune, and vascular cells, represent a critical determinant of therapeutic response. In this review, we focus on preclinical models that can be used to explore these interactions, identify new therapeutic targets, and test combination therapies. In particular, we will describe the use of implantable orthotopic immunocompetent models employing a panel of murine lung adenocarcinoma cell lines with oncogenic drivers common to human lung adenocarcinoma as a powerful system to develop new treatment approaches. Full article

Background: TNBC patients respond poorly to chemotherapy, leading to high mortality rates and a worsening prognosis. Here, we investigated the effect of M-I on TNBC tumor growth suppression and its potential mechanisms. Methods: Signaling pathways were analyzed to study the effect of M-I on TNBC cells (human MDA-MB-231 and mouse 4T1). We used orthotopic mouse models to examine the anti-tumor efficacy of M-I. Tumor volume and the status of tumor-associated macrophages (TAMs) were assessed by qRT-PCR or FACS analysis. Results: We found a significant dose- and time-dependent inhibition of TNBC cell proliferation following treatment with M-I. Cell cycle analysis revealed a shortened S phase in M-I-treated cells and downregulation of AURKA, PLK1, CDC25c, CDK1, and cyclinB1. Furthermore, M-I treatment reduced the expression of pSTAT3, cyclinD1, and c-Myc in TNBC cells. To evaluate the anti-tumor efficacy of M-I, we employed orthotopic TNBC mouse models and observed a significant reduction in tumor growth without measurable toxicity. Next, we analyzed RNA from control and M-I-treated tumors to further assess the status of TAMs and observed a significant decrease in M2-like macrophages in the M-I-treated group. Immortalized bone marrow-derived mouse macrophages (iMacs) exposed to conditioned media (CM) of TNBC cells with or without M-I treatment indicated that the M-I treated CM of TNBC cells significantly reduce the M2phenotype in iMacs. Mechanistically, we found that M-I specifically targets the IL-4/MAPK signaling axis to reduce immunosuppressive M2 macrophage polarization. Conclusions: Our study reveals a novel mechanism by which M-I inhibits TNBC cell proliferation by regulating intracellular signaling and altering TAMs in the tumor microenvironment and highlights its potential as a promising candidate for TNBC therapy. Full article

Lobelia nummularia Lam. is a traditional medicinal herb of which the anticancer mechanisms remain largely unexplored. Here, we demonstrated that its ethanolic extract (LNE) exerts potent anti-breast cancer activity by inducing ROS-dependent mitochondrial apoptosis in MDA-MB-231 cells, a mechanism confirmed via rescue experiments with the antioxidant N-acetylcysteine (NAC). This pro-apoptotic program is driven by a dual mechanism: potent suppression of the pro-survival EGFR/PI3K/AKT signaling pathway and simultaneous activation of the TP53-mediated apoptotic cascade, culminating in the cleavage of executor caspase-3. Phytochemical analysis identified numerous flavonoids, and quantitative HPLC confirmed that key bioactive compounds, including luteolin and apigenin, are substantially present in the extract. These mechanisms translated to significant in vivo efficacy, where LNE administration suppressed primary tumor growth and lung metastasis in a 4T1 orthotopic model in BALB/c mice. Furthermore, a validated molecular docking protocol provided a plausible structural basis for these multi-target interactions. Collectively, this study provides a comprehensive, multi-layered validation of LNE’s therapeutic potential, establishing it as a mechanistically well-defined candidate for natural product-based anticancer drug discovery. Full article

This study aimed to clarify the alterations in gene expression in metastatic renal cell carcinoma (mRCC) during disease progression and in response to treatment with immune checkpoint inhibitors using a syngeneic mouse mRCC model. RENCA cells were orthotopically implanted in BALB/c mice. Mice received first-line treatment with cabozantinib, anti-PD-1 antibody, or a combination. Tumor progression was monitored using serial micro-computed tomography. Lung metastasis samples were collected, and RNA sequencing was performed. Mice with apparent disease progression received second-line treatment with axitinib, everolimus, or lenvatinib after combination therapy. The median overall survival was 28, 34, 34, and 49 days in untreated mice and those treated with cabozantinib, anti-PD-1, or their combination, respectively (p < 0.05). RNA sequencing revealed upregulation of the fibroblast growth factor pathway in lung metastases after monotherapy, whereas mTOR pathway activation was observed only after combination therapy. Treatment-specific gene expression changes occur in mRCC, suggesting that the optimal target for sequential therapy in mRCC varies depending on prior treatment. Full article

Background: To overcome the limitations of conventional CRC (colorectal cancer) mouse models in replicating metastasis and enabling efficient therapeutic evaluation, we developed a novel implantation method using tissue adhesive to establish reproducible orthotopic and metastatic tumors. Conventional models using injection or suturing techniques often suffer from technical complexity, inconsistent tumor establishment, and limited metastatic reliability. Methods: We developed and validated a novel orthotopic and metastatic CRC model utilizing tissue adhesive for tumor transplantation. Uniform tumor fragments derived from bioluminescent HCT116/Luc xenografts were affixed to the cecum of nude mice. Tumor growth and metastasis were monitored through bioluminescence imaging and confirmed by the results of histological analysis of metastatic lesions. The model’s utility for therapeutic testing was evaluated using MK801, an NMDA receptor antagonist. Results: The biological-based model demonstrated rapid and reproducible tumor implantation (<5 min), consistent primary tumor growth, and robust metastasis to the liver and lungs. The biological-based approach achieved 80% tumor engraftment (4/5), with consistent metastasis to the liver and lungs in all mice, compared with lower and variable metastasis rates in injection (0%, 0/5) and suturing (20%, 1/5) methods. MK801 treatment significantly suppressed both primary tumor growth and metastasis, validating the model’s suitability for preclinical drug evaluation. Conclusions: By enabling rapid, reproducible, and spontaneous formation of metastatic lesions using a minimally invasive tissue adhesive technique, our model represents a significant methodological advancement that supports high-throughput therapeutic screening and bridges the gap between experimental modeling and clinical relevance in colorectal cancer research. Full article

Pancreatic cancer is the third leading cause of cancer-related death in the US. First-line chemotherapy regimens for pancreatic ductal adenocarcinoma (PDAC) include FOLFIRINOX or gemcitabine (Gem) with or without paclitaxel (Ptx); however, 5-year survival with these regimens remains poor. Previous work has demonstrated protein arginine methyltransferase 5 (PRMT5) to be a promising therapeutic target in combination with Gem for the treatment of PDAC; however, these findings have yet to be confirmed in relevant preclinical models of PDAC. To test the possibility of PRMT5 as a viable therapeutic target, clinically relevant orthotopic and metastatic patient-derived xenograft (PDX) mouse models of PDAC growth were utilized to evaluate the effect of PRMT5 knockout (KO) or pharmacologic inhibition on treatment with Gem alone or Gem with Ptx. Primary endpoints included tumor volume, tumor weight, or metastatic tumor burden as appropriate. The results showed that Gem-treated PRMT5 KO tumors exhibited decreased growth and were smaller in size compared to Gem-treated wild-type (WT) tumors. Similarly, the Gem-treated PRMT5 KO metastatic burden was lower than the Gem-treated WT metastatic burden. The addition of a PRMT5 pharmacologic inhibitor to Gem and Ptx therapy resulted in a lower final tumor weight and fewer metastatic tumors. The depletion of PRMT5 results in increased DNA damage in response to Gem and Ptx treatment. Thus, PRMT5 genetic depletion or inhibition in combination with Gem-based therapy improved the response in primary and metastatic PDAC in clinically relevant mouse models, suggesting that PRMT5 is a viable therapeutic target for combination therapy in PDAC. Full article

Glioblastoma (GBM) is the most aggressive form of malignant gliomas, with the eicosanoid-synthesizing enzyme cyclooxygenase-2 (COX-2) playing a pivotal role in its progression via the COX-2/prostaglandin E2/4 axis. COX-2 upregulations in tumor cells induces a pro-inflammatory tumor microenvironment (TME), affecting the behavior of invading bone marrow-derived macrophages (Mϕ) and brain-resident microglia (MG) through unclear autocrine and paracrine mechanisms. Using CRISPR/Cas9 technology, we generated COX-2 knockout U87 glioblastoma cells. In spheroids and in vivo xenografts, this resulted in a significant inhibition of tumorigenic properties, while not observed in standard adherent monolayer culture. Here, the knockout induced a G1 cell cycle arrest in adherent cells, accompanied by increased ROS, mitochondrial activity, and cytochrome c-mediated apoptosis. In spheroids and xenograft models, COX-2 knockout led to notable growth delays and increased cell death, characterized by features of both apoptosis and autophagy. Interestingly, these effects were partially reversed in subcutaneous xenografts after co-culture with Mϕ, while co-culture with MG enhanced the growth-suppressive effects. In an orthotopic model, COX-2 knockout tumors displayed reduced proliferation (fewer Ki-67 positive cells), increased numbers of GFAP-positive astrocytes, and signs of membrane blebbing. These findings highlight the potential of COX-2 knockout and suppression as a therapeutic strategy in GBM, particularly when combined with suppression of infiltrating macrophages and stabilization of resident microglia populations to enhance anti-tumor effects. Full article

Prostate cancer is the second leading cause of cancer-related death in men, with metastatic castration-resistant prostate cancer (mCRPC) and bone metastases representing a critical clinical challenge. Although radium-223 (Ra-223) is approved for treating mCRPC with bone metastases, its efficacy remains limited, necessitating the development of more effective therapies. This study investigates the therapeutic potential of ¹⁷⁷Lu-PSMA-617, a PSMA-targeted radiopharmaceutical, in a murine model of prostate cancer bone metastases. To our knowledge, this is the first study to systematically evaluate ¹⁷⁷Lu-PSMA-617 in an orthotopic bone metastatic prostate cancer model, providing a clinically relevant preclinical platform to assess both imaging and therapeutic performance. We conducted comprehensive preclinical evaluations, including synthesis, stability analysis, cell binding assays, nuclear imaging, in vivo biodistribution, pharmacokinetics, and antitumor efficacy. The synthesis of ¹⁷⁷Lu-PSMA-617 demonstrated high radiochemical yield (99.2%), molar activity (25.5 GBq/μmol), and purity (>98%), indicating high product quality. Stability studies confirmed minimal release of free Lutetium-177, maintaining the compound’s integrity under physiological conditions. In vitro assays showed selective binding and internalization in PSMA-positive LNCaP prostate cancer cells, with negligible uptake in PSMA-negative PC-3 cells. In vivo biodistribution studies demonstrated efficient tumor targeting, with peak uptake in LNCaP tumors (23.31 ± 0.94 %IA/g) at 4 h post-injection. The radiopharmaceutical exhibited favorable pharmacokinetics, with high tumor-to-background ratios (tumor-to-blood, 434.4; tumor-to-muscle, 857.4). Therapeutic efficacy was confirmed by significant survival extension in treated mice (30.7% for 37 MBq and 53.8% for 111 MBq), with median survival times of 34 and 40 days, respectively, compared to 26 days in the control group. Radiation dosimetry analysis indicated a favorable safety profile with a calculated effective dose of 0.127 mSv/MBq. These findings highlight the novelty and translational relevance of using ¹⁷⁷Lu-PSMA-617 in a clinically relevant bone metastasis model, reinforcing its potential as a dual-purpose agent for both targeted therapy and molecular imaging in advanced prostate cancer. Full article

Background/Objectives: Pancreatic cancer is the fourth leading cause of deaths related to cancer. It is a highly aggressive malignancy and often metastasizes quickly to other parts of the body and organs. The most effective cure is surgical resection, which also is limited by tumor identification and clear tumor margin visualization. Previously, we used MUC4 antibodies labeled with IRDye800CW (anti-MUC4-IR800) to target primary human pancreatic cancer in orthotopic cell line mouse models. Methods: In the present study, we established a pancreatic cancer liver metastasis mouse model by implanting a tumor fragment in the liver and a peritoneal carcinomatosis mouse model by injecting pancreatic cancer cells interperitoneally. Once the tumors were established, anti-MUC4-IR800 was administered to the mice by tail vein injection. Laparotomy was performed and tumors were imaged under white-light and near-infrared (NIR) fluorescence with the Pearl Small Animal Imaging System. Results: NIR imaging after 72 h shows the bright targeting of pancreatic cancer metastasis in both mouse models with high tumor-to-background ratios. Conclusions: Anti-MUC4-IR800 was able to successfully target and brightly label metastatic pancreatic cancer as small as 1 mm. Future clinical applications of the results of the present study are discussed. Full article

Background/Objectives:Cancer vaccine targets mostly include mutations and overexpressed proteins. However, cancer-associated post-translational modifications (PTMs) may also induce immune responses. Previously, our group established the enzyme protein arginine deiminase type-2 (PADI2), which catalyzes citrullination modification, is highly expressed in triple-negative breast cancer (TNBC), promoting antigenicity. Methods: Here, we show the workflow of designing citrullinated enolase 1 (citENO1) vaccine peptides identified from breast cancer cells by mass spectrometry and demonstrate TNBC vaccine efficacy in the mouse model. Immunized mice with citENO1 peptides or the corresponding unmodified peptides, plus Poly I:C as an adjuvant, were orthotopically implanted with a TNBC murine cell line. Results: Vaccination with citENO1, but not unmodified ENO1 (umENO1), induced a greater percentage of activated CD8+ PD-1+ T cells and effector memory T cells in skin-draining lymph nodes (SDLNs). Remarkably, the citENO1 vaccine delayed tumor growth and prolonged overall survival, which was further enhanced by PD-1 blockade. Conclusions: Our data suggest that cancer-restricted post-translational modifications provide a source of vaccines that induce an anti-cancer immune response. Full article

Background/Objectives: Cryotherapy involves the insertion of cryoprobes into tumors to induce cell destruction through exposure to extremely low temperatures over several minutes. This localized treatment modality may enhance the efficacy of established therapies, such as radiotherapy, particularly for glioblastomas. Our study aimed to provide proof-of-concept for the efficacy of combining cryotherapy and radiotherapy in the treatment of subcutaneous murine brain tumors (GL-261) in immunocompetent C57BL/6 mice. Methods: Tumor growth, survival and response were evaluated using MRI and histological analysis. Results: Partial cryotherapy alone showed no therapeutic efficacy. However, combining cryotherapy with radiotherapy significantly potentiated treatment outcomes. A statistically significant survival benefit was observed in the combined therapy group compared to control, cryotherapy and radiotherapy groups. Notably, 40% of mice receiving the combined treatment exhibited complete responses, with no detectable tumor cells on MRI or histological analysis. Furthermore, MRI-based monitoring revealed that the Apparent Diffusion Coefficient (ADC) map could predict complete response 14 days post-treatment, unlike caliper-based measurements. Conclusions: These findings suggest that cryotherapy may enhance radiotherapy efficacy, resulting in complete tumor regression in 4 out of 10 cases. ADC distribution may serve as a predictive marker for therapeutic response. However, given the limitations of the model, further studies in orthotopic models are needed to validate these findings and assess their clinical relevance. Full article

Background/Objectives: Our laboratory has been developing a Sindbis viral (SV) vector platform for treatments of several types of cancers. In this study, we assess treatment efficacy for metastatic and immunosuppressive pancreatic cancer. Methods: Orthotopic mouse models were generated by injection of tumor cells into the pancreatic parenchyma. Sindbis vectors were inoculated intraperitoneally. Imaging of tumors was performed by either MRI or in vivo imaging using luciferase. Flow cytometry, multi-immunofluorescence and elispot analysis were performed for certain tumors. Results: SV can infect and reduce pancreatic tumors in three mouse model systems: a model bearing human pancreatic tumors, a highly metastatic model, and a model that reflects the highly immunosuppressive, desmoplastic microenvironment common to human pancreatic cancer. Conclusions: Combination of SV vector expressing IL12 with an immune co-stimulatory agent, anti-OX40, can reduce tumors, facilitate an influx of immune response cells into the tumor microenvironment, and prevent tumors in mice rechallenged with tumor cells promising an effective treatment for pancreatic cancer. Full article

Dauricine has been shown to possess intriguing anti-cancerous activities against various malignancies. The current study examined the inhibitory effects of dauricine against lung adenocarcinoma with cell lines and animal models. MTT assay was performed in three different lung adenocarcinoma cell lines using a concentration range of dauricine. Colony formation, wound healing, Edu incorporation, and cell cycle analysis were conducted to investigate the impact of dauricine on lung adenocarcinoma cells in vitro. Moreover, flow cytometry was performed to observe the effect of dauricine on cellular ROS levels. The expression of redox regulator Nrf2 and apoptosis-related markers was assessed by Western blot. Importantly, the anti-tumor efficacy of dauricine was studied in vivo with two lung adenocarcinoma animal models, including a subcutaneous cell line-derived syngeneic model and an inducible orthotopic KRAS^G12D-driven lung adenocarcinoma model. The proliferation and migration of lung adenocarcinoma cells were significantly reduced by dauricine treatment. Flow cytometry analysis revealed that dauricine treatment resulted in cell cycle arrest at G0/G1 phases in A549, H1299, and A427 cells. Intracellular ROS levels were markedly augmented by dauricine treatment. Notably, dauricine led to the downregulation of the master redox regulator Nrf2. Meanwhile, dauricine treatment resulted in decreased Bcl-2 levels but elevated expression of BAX and cleaved Caspase 3. Finally, dauricine demonstrated significant efficacy in restricting tumor progression in both subcutaneous syngeneic and orthotopic lung adenocarcinoma models. Our results corroborate the anti-cancer effects of dauricine against lung adenocarcinoma with in vivo and in vitro analyses. Our findings also provide mechanistic evidence that links the impact of dauricine to cell cycle blockage and ROS-mediated apoptosis. Full article