Reduced Tumor Growth Research Articles

The diverse landscape of RNA modifications in cancer development and progression.

RNA modifications, a central aspect of epitranscriptomics, add a regulatory layer to gene expression by modifying RNA function without altering nucleotide sequences. These modifications play vital roles across RNA species, influencing RNA stability, translation, and interaction dynamics, and are regulated by specific enzymes that add, remove, and interpret these chemical marks. This review examines the role of aberrant RNA modifications in cancer progression, exploring their potential as diagnostic and prognostic biomarkers and as therapeutic targets. We focus on how altered RNA modification patterns impact oncogenes, tumor suppressor genes, and overall tumor behavior. We performed an in-depth analysis of recent studies and advances in RNA modification research, highlighting key types and functions of RNA modifications and their roles in cancer biology. Studies involving preclinical models targeting RNA-modifying enzymes were reviewed to assess therapeutic efficacy and potential clinical applications. Aberrant RNA modifications were found to significantly influence cancer initiation, growth, and metastasis. Dysregulation of RNA-modifying enzymes led to altered gene expression profiles in oncogenes and tumor suppressors, correlating with tumor aggressiveness, patient outcomes, and response to immunotherapy. Notably, inhibitors of these enzymes demonstrated potential in preclinical models by reducing tumor growth and enhancing the efficacy of existing cancer treatments. RNA modifications present promising avenues for cancer diagnosis, prognosis, and therapy. Understanding the mechanisms of RNA modification dysregulation is essential for developing targeted treatments that improve patient outcomes. Further research will deepen insights into these pathways and support the clinical translation of RNA modification-targeted therapies.

NK cells-derived extracellular vesicles potency in the B cell lymphoma biotherapy

IntroductionExtracellular vesicles of Natural Killer cells (NKEV) exert an antitumor effect towards hematopoietic and solid tumors and have an immune modulating effect, suggesting a promising role in immune and biotherapy. In this study, a continuation of our former works, we demonstrated a network by mass spectrometry analysis between NKEV protein cargo and antitumor effects. Human healthy NKEV, both exosomes and microvesicles, have a significant and direct cytotoxic effect against human B cell lymphoma in in vitro and in vivo conditions.MethodsWe isolated extracellular vesicles from in vitro amplified healthy human NK cells and their treatment efficacy was monitored by cytometry analyses, in vivo MRI/MRS measurements, ex vivo MRS analyses and immunohistochemistry.ResultsWe observed a remarkable NKEV cytotoxic effect, mainly by apoptosis, on B cell lymphoma in vitro when exosomes and microvesicles were administered simultaneously. In vivo results showed metabolic alterations in SCID mice xenografts after NKEV treatment, associated with a significant reduction of tumor growth (64%). In the in vivo1H MR spectra we found a significant increase in the tumor lipid/lactate and in taurine signals, both considered as apotosis markers. Ex vivo lymphoma metabolomics revealed a significant increase in fatty acid (FA) pool and decrease in unsaturated and mono-unsaturated FA in treated groups, as compared to control one, thus suggesting an alteration of tumor homeostasis. Immunohistochemistry analyses confirmed the reduction of B-cell lymphoma proliferation rate, as well as the induction of apoptosis following the NKEV treatment. ConclusionsThis study underscore the importance of NKEV as a novel biological acellular tool for B-cell lymphoma treatment, probably having a greater effect on combined treatment regimens. These nanovesicles have an extraordinary potential in innovative cancer immunotherapy, representing a safe and efficient tool naturally circulating in healthy individuals and ready to maintain the immune homeostasis, and therefore a good organism healthy state.

Asparagus officinalis L. extract exhibits anti-proliferative and anti-invasive effects in endometrial cancer cells and a transgenic mouse model of endometrial cancer

IntroductionEndometrial cancer is the most common malignancy of the female reproductive system in the United States. Asparagus officinalis is a versatile, nutrient-dense, low-calorie vegetable that contains various bioactive metabolites that have shown a variety of biologic functions beneficial to health. The metabolites from asparagus officinalis extracts or asparagus officinalis extracts exhibit significant anti-tumorigenic activity in some pre-clinical models of cancer.MethodsEndometrial cancer cells were used to study the effects of asparagus officinalis on anti-proliferation, anti-invasion and increased sensitivity to cisplatin, and obese and lean Lkb1fl/flp53fl/fl mouse model of endometrial cancer was used to study the role of asparagus officinalis in tumor growth.ResultsTreatment with increasing concentrations of Asparagus officinalis extracts significantly inhibited cell proliferation, reduced glycolytic activity, induced cellular stress and apoptosis, caused cell cycle G1 arrest, increased the sensitivity of cells to cisplatin, reduced cell adhesion and invasion, and activation of AMPK and inhibition of the AKT/mTOR and MAPK signaling pathways in endometrial cancer cells. Moreover, asparagus officinalis extracts suppressed cell adhesion and invasion through the modulation of the epithelial-to-mesenchymal transition process. Asparagus officinalis extract treatment for 4 weeks resulted in a significant reduction in tumor growth in Lkb1fl/flp53fl/fl mice under both obese and lean conditions, with a decrease in Ki-67 and vascular endothelial growth factor expression and an increase in Bip expression in endometrial tumors.DiscussionThese findings provide strong preclinical evidence for the potential therapeutic benefit of asparagus officinalis extract as a novel dietary strategy in the treatment of endometrial cancer. Further clinical trials of dietary intervention of asparagus officinalis or combination with cisplatin in patients with endometrial cancer are warranted.

Durable antitumor response via an oncolytic virus encoding decoy-resistant IL-18

BackgroundInterleukin-18 (IL-18), or interferon (IFN)-γ-inducing factor, potentiates T helper 1 and natural killer cell activation as well as CD8+ T-cell proliferation. Recombinant IL-18 has displayed limited clinical efficacy in part...

A stearate-rich diet and oleate restriction directly inhibit tumor growth via the unfolded protein response.

Fatty acids are known to have significant effects on the properties of cancer cells. Therefore, these compounds have been incorporated into therapeutic strategies. However, few studies have examined the effects of individual fatty acids and their interactions in depth. This study analyzed the effects of various fatty acids on cancer cells and revealed that stearic acid, an abundant saturated fatty acid, had a stronger inhibitory effect on cell growth than did palmitic acid, which is also an abundant saturated fatty acid, by inducing DNA damage and apoptosis through the unfolded protein response (UPR) pathway. Intriguingly, the negative effects of stearate were reduced by the presence of oleate, a different type of abundant fatty acid. We combined a stearate-rich diet with the inhibition of stearoyl-CoA desaturase-1 to explore the impact of diet on tumor growth. This intervention significantly reduced tumor growth in both ovarian cancer models and patient-derived xenografts (PDXs), including those with chemotherapy resistance, notably by increasing stearate levels while reducing oleate levels within the tumors. Conversely, the negative effects of a stearate-rich diet were mitigated by an oleate-rich diet. This study revealed that dietary stearate can directly inhibit tumor growth through mechanisms involving DNA damage and apoptosis mediated by the UPR pathway. These results suggest that dietary interventions, which increase stearic acid levels while decreasing oleic acid levels, may be promising therapeutic strategies for cancer treatment. These results could lead to the development of new cancer treatment strategies.

Peimine induces apoptosis of glioblastoma cells through regulation of the PI3K/AKT signaling pathway.

Glioblastoma (GBM) is one of the most malignant forms of intracranial tumors, with high mortality rates and invariably poor prognosis, due to the limited clinical treatment strategies available. As a natural compound, peimine's favorable pharmacological activities have been widely revealed. However, potential inhibitory effects of peimine on GBM have not been explored. In the present study, both in vitro and in vivo experiments were performed to elucidate the effects of peimine on GBM and to further delineate the underlying molecular mechanism of action. Different doses (0, 25 and 50 µM) of peimine were added to U87 cells, before MTT, colony formation, wound healing, Transwell migration and invasion, reactive oxygen species and mitochondrial transmembrane potential assays were used to measure proliferation, migration, invasion and apoptosis. Furthermore, western blotting was used to examine the possible effects of peimine on the expression of proteins associated with apoptosis and the PI3K/AKT signaling pathway. Subsequently, a GBM mouse xenograft model was used to assess the effects of peimine in vivo. The findings showed that peimine inhibited GBM proliferation, migration and invasion in a dose-dependent manner, whilst also inducing apoptosis. Peimine also reduced tumor growth in vivo. Mechanistically, peimine downregulated the expression of Bcl-2 and Caspase 3, whilst upregulating the protein expression levels of p53, Bax and Cleaved-Caspase 3 in a dose-dependent manner. In addition, PI3K and AKT phosphorylation levels were found to be decreased by peimine in a dose-dependent manner. In conclusion, these findings suggest that peimine may limit GBM growth by regulating the PI3K/AKT signaling pathway both in vitro and in vivo. These findings may have promising clinical implications.

Mitochondrial-Targeting Strategies with Homoharringtonine: A Novel Approach for Chemoresistant Rectal Cancer

5-Fluorouracil (5-FU) resistance poses a significant challenge in the treatment of rectal cancer, driving the need for novel therapeutic strategies. In this study, we established 5-FU-resistant rectal cancer cell lines (SW837-r, SNU-C1-r) and identified homoharringtonine (HHT) as a potent and selective anticancer agent through high-throughput drug screening of 291 compounds. HHT displayed the highest selective drug sensitivity score (sDSS), showing strong activity against resistant cells while sparing normal rectal epithelial cells. Further investigations revealed that 5-FU-resistant cells exhibited enhanced mitochondrial biogenesis and function compared to normal cells, and HHT exerted its cytotoxic effects by targeting mitochondrial respiration. HHT significantly reduced oxygen consumption rate (OCR), mitochondrial complex I activity, and ATP production in resistant cells, with mitochondrial respiration-deficient ρ0 cells showing reduced sensitivity to HHT. In vivo, HHT alone reduced tumor growth by 60% in the resistant xenograft model. In the sensitive xenograft model, combination therapy with 5-FU achieved an 85% reduction in tumor volume compared to controls, with tumors in the combination group displaying minimal regrowth. These results demonstrate that HHT effectively targets mitochondrial function in resistant rectal cancer cells and, in combination with 5-FU, offers synergistic antitumor effects and prolonged tumor suppression. The favorable safety profile of HHT further highlights its potential as a promising therapeutic agent for overcoming 5-FU resistance in rectal cancer.

Investigation of Effectiveness of Nowarta110 Against Murine Malignant Melanoma in an Implanted Animal Model.

Melanoma is a prevalent and severe disease, making the development of new treatments essential. Nowata110 has demonstrated significant therapeutic efficacy in phase II clinical study against plantar warts. It has shown promising anti-cancer effects in both in vitro and in vivo studies using HPV-16 and HPV-18-induced cervical cancer models. This study evaluated the effectiveness of Nowarta110 in murine melanoma-implanted animals. Nowata110 is a novel compound composed of colloidal silver and fig extract. Male and female immunodeficient C(Cg)-Cd 79 atm 1 (cre) and immunocompetent BALB/c mice were used. Murine melanoma cancer cells (B16-F10) were implanted subcutaneously in experimental animals. Once the top cross-sectional area of tumors reached a minimum of 5 mm2 and approximately 4 mm depth, mice were anesthetized and treated with Nowarta110 intravenously or intratumorally. Control mice received no treatment. In non-treated immunodeficient mice, tumor growth progressed over five weeks, whereas Nowarta110-treated mice drastically reduced tumor volume until five weeks after treatment was initiated. Similarly, in untreated BALB/c mice, tumor growth persisted over five weeks. However, Nowarta110-treated mice exhibited a notable reduction in tumor size. Although intravenous administration of Nowarta110 did not result in complete tumor regression in immunodeficient mice, it did lead to reduced tumor growth. In BALB/c immunocompetent mice, intravenous treatment generally stalled tumor progression. Intratumoral and intravenous administration of Nowarta110 effectively treated murine melanoma in immunodeficient and immunocompetent mice. The Nowarta110 antitumoral efficacy was more pronounced in immunocompetent mice treated intravenously than immunodeficient mice. Clinical studies to examine the efficacy of Nowarta110 in human melanoma and skin cancers are warranted.

RNA binding protein RBM22 suppresses non-small cell lung cancer tumorigenesis by stabilizing LATS1 mRNA.

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related mortality worldwide. Despite advancements in diagnostics and therapeutics, the prognosis for NSCLC remains poor, highlighting the urgent need for novel treatment options. RNA binding proteins, particularly RBM22, have emerged as significant contributors to cancer progression by influencing RNA splicing and gene expression. This study investigates the role of RBM22 in NSCLC and its potential as a therapeutic target. We focus on the effects of RBM22 on cell proliferation, invasion, stemness, and its interaction with LATS1 mRNA. RBM22 expression was assessed in samples and cell lines of NSCLC through techniques such as real-time PCR and western blot analysis. To modify RBM22 levels, overexpression and knockdown methods were employed utilizing vectors and siRNAs. We conducted assays for cell proliferation, invasion, and stemness to evaluate the effects of altering RBM22. The interaction between RBM22 and LATS1 mRNA was investigated using RNA immunoprecipitation. In addition, in vivo studies involving subdermal tumor and lung metastasis models in athymic mice were carried out to evaluate how changes in RBM22 influence the tumorigenic and metastatic characteristics of NSCLC. Our analysis revealed a significant underexpression of RBM22 in NSCLC tissues compared to adjacent healthy tissues. Increasing RBM22 expression in NSCLC cell lines led to a marked decrease in cellular proliferation, invasiveness, and stemness, while silencing RBM22 produced opposing effects. Further investigations confirmed that RBM22 directly interacts with LATS1 mRNA, thereby stabilizing and enhancing its expression. In vivo studies validated that elevated RBM22 expression substantially reduced tumor formation and pulmonary metastases, as evidenced by decreased tumor size, mass, and Ki-67 proliferation marker expression, along with a significant reduction in the number of metastatic nodules in the lungs. Our study demonstrates that RBM22 suppresses NSCLC by stabilizing LATS1 mRNA, which in turn reduces tumor growth and metastasis. Consequently, RBM22 emerges as a valuable therapeutic target for NSCLC, offering new strategies for addressing this challenging condition.

Albumin and Polysorbate-80 Coated Sterile Nanosuspensions of Mebendazole for Glioblastoma Therapy.

The scarcity of existing and novel therapies for brain cancer has significantly affected the survival rate of glioblastoma patients. Mebendazole (MBZ), an antiparasitic agent demonstrated promising activity against brain cancer. However, poor solubility, multiple polymorphs, and insufficient permeability through blood-brain barrier (BBB) restricts its therapeutic efficacy through parenteral administration. The current study aimed to develop, optimize, and characterize sterile, injectable nanosuspension of mebendazole using parenterally acceptable stabilizers. Albumin and polysorbate 80 (PS-80) coated MBZ Nanosuspension (NS) was prepared using wet media milling technique. Design of experiment (DoE) approach was used to understand effect of drug loading versus stabilizer concentration. The optimized MBZ NS showed hydrodynamic diameter of 208.36 ± 0.24 nm with a poly dispersibility index (PDI) of 0.210 ± 0.03 and zeta potential of -20.41 ± 0.36 mV. The IC50 value of MBZ NS in U-87 MG and LN-229 cell lines were found to be 0.49 ± 0.02 μM and 0.48 ± 0.05 μM, respectively. Additionally, MBZ NS demonstrated a 2.65-fold decrease in colony-forming efficiency and a 1.16-fold reduction in migration of the bridging area compared to MBZ. In 3D spheroids of the U-87 MG glioma cell line, MBZ NS exhibited a 50% reduction in tumor growth and increased cell apoptosis compared to the control. MBZ NS formulations were sterilized by gamma irradiation and tested as per the USP sterility test. Albumin-PS 80 coated NS is rendered to be useful parenteral delivery of mebendazole for the treatment of brain cancer.

RNA N6-Methyladenosine-Binding Protein YTHDFs Redundantly Attenuate Cancer Immunity by Downregulating IFN-γ Signaling in Gastric Cancer.

Immunotherapy holds potential as a treatment for gastric cancer (GC), though immune checkpoint inhibitor (ICI) resistance remains an obstacle. One resistance mechanism involves defects in interferon-γ (IFN-γ) signaling, in which IFN-γ is linked to improved responsiveness to ICIs. Herein, the roles of RNA N6-methyladenosine (m6A) modifications in regulation of IFN-γ signaling and the responsiveness to ICIs are unveiled. The m6A-binding protein YTH N6-methyladenosine RNA-binding protein F1 (YTHDF1) is overexpressed in GC tissues, correlating with the suppression of cancer immunity and poorer survival rates. YTHDF1 overexpression impaired the responsiveness to IFN-γ in GC cells, and knockdown studies indicated the redundant effects of YTHDF2 and YTHDF3 with YTHDF1 in IFN-γ responsiveness. RNA immunoprecipitation sequencing revealed YTHDFs directly target interferon regulatory factor 1 (IRF1) mRNA, a master regulator of IFN-γ signaling, leading to reduced RNA stability and consequent downregulation of IFN-γ signaling. Furthermore, in mouse syngeneic tumor models, Ythdf1 depletion in cancer cells resulted in reduced tumor growth and increased tumor-infiltrating lymphocytes, which are attributed to the augmentation of IFN-γ signaling. Collectively, these findings highlight how YTHDFs modulate cancer immunity by influencing IFN-γ signaling through IRF1 regulation, suggesting their viability as therapeutic targets in cancer immunotherapy.

FAK inhibition suppresses breast cancer progression via DNA methylation-mediated DAB2 gene reactivation.

Epigenetic silencing of tumor suppressor genes is one of the main drivers of tumor progression. Without these tumor suppressors to reduce proliferation, tumor cells proliferate unchecked. Focal adhesion kinase (FAK) is a tyrosine kinase which is often upregulated in various tumors and promotes cell proliferation and migration. Recent studies have demonstrated that pharmacological or genetic FAK inhibition can reduce suppressive DNA methylation in vascular cells. Mechanistically, this is through nuclear FAK-mediated ubiquitination and proteasomal degradation of DNA methyltransferase 3A (DNMT3A). Treatment of breast cancer cell lines with FAK inhibitor (FAK-I) was able to reduce both FAK activity and DNMT3A protein expression. Further, global DNA methylation was reduced in breast cancer cell lines treated with FAK-I. This decrease in DNA methylation was correlated with decreased cell proliferation. We further showed that FAK-I reduced DNMT3A expression in breast cancer cells and that treatment with the proteasome inhibitor MG132 prevented loss of DNTM3A protein stability. To identify how FAK-I and DNMT3A loss could reduce breast cancer cell growth we compared RNA sequencing data from breast cancer cells treated with or without FAK-I or in shRNA DNMT3A knockdown. We have identified a potential tumor suppressor, DAB2, as being regulated by the nuclear FAK-DNMT3A axis. DAB2 is often downregulated in cancers and has been shown to play a vital role in switching TGFβ signaling from proliferative to apoptotic by altering TGFβRI binding partners. Immunoblotting and immunostaining indeed revealed that FAK-I and shDNMT3A could induce DAB2 protein expression. Further, FAK-I treatment showed efficacy in reducing tumor growth in vivo using the murine 4T1 tumor model. Immunostaining of 4T1 tumors showed FAK-I decreased DNMT3A, DNA methylation (5-methylcytosine, 5-mC), and increased DAB2 expression. Taken together, these data suggest that nuclear FAK-mediated regulation of DNMT3A can alter the epigenetic landscape and induce tumor suppressor gene expression.

Dual-phase nanoscissors disrupt vasculature-breast cancer stem cell crosstalk for breast cancer treatment

Clinical treatment effects of breast cancer are heavily frustrated by the malignant crosstalk between tumor vasculature and breast cancer stem cells (BCSCs). This study introduces a two-phase therapeutic strategy targeting the interplay between tumor vasculature and BCSCs to overcome this challenge. Here, we designed an FLG/ZnPc nanoscissor, which combines mild photodynamic therapy (PDT) to generate reactive oxygen species (ROS) with vascular normalization therapy (VNT) to break the crosstalk between tumor vessels and BCSCs. In the first phase, our approach breaks the vascular niche that supports BCSCs by restoring tumor vascular function and promoting ROS-induced BCSCs differentiation into less malignant forms, enhancing treatment sensitivity. The second phase employs high-impact photothermal therapy (PTT) to ablate tumor masses. This integrated “mild PDT-PTT” approach aims to reduce tumor growth and metastasis, offering a comprehensive strategy for effective breast cancer management.

Heme oxygenase 1 inhibitor discovery and formulation into nanostructured lipid carriers as potent and selective treatment against triple negative metastatic breast cancer

Heme oxygenase-1 (HO-1) has been identified as a potential new target in anticancer therapy, being overexpressed in different tumors and crucial for cell proliferation. Advances in the development of specific HO-1 inhibitors should support the understanding of controlling HO-1 activity as antitumoral strategies, opening the path for future therapeutic applications. In the present study, small series of new HO-1 inhibitors were synthesized by joining a butylimidazolic pharmacophore together with a hydrophobic moiety spaced by a 2-oxybenzamide central linker. The most active and selective HO-1 inhibitor, VP 21–04, 2-(4-(1H-imidazol-1-yl)butoxy)-N-benzyl-5-iodobenzamide (7b) was identified. This ligand showed strong cytotoxic activity against melanoma and breast cancer cell lines. Encapsulation of VP 21–04 in nanostructured lipid carriers (NLC 21–04) was performed to exploit its therapeutic potential by passive-targeting delivery ameliorating water-solubility and toxicity. Interestingly, NLC 21–04 showed a marked antiproliferative effect in both cancer cell lines, and an improved safety profile with a wider therapeutic window when compared to the free drug. Finally, NLC 21–04 showed a marked tumor growth reduction while being safe in an in ovo tumor model, highlighting the therapeutic potential of the developed nanoparticles against triple negative metastatic breast cancer.

Platelet factor 4-induced TH1-Treg polarization suppresses antitumor immunity.

The tumor microenvironment (TME) contains a number of immune-suppressive cells such as T helper 1-polarized regulatory T cells (TH1-Treg cells). However, little is known about the mechanism behind the abundant presence of TH1-Treg cells in the TME. We demonstrate that selective depletion of arginase I (Arg1)-expressing tumor-associated macrophages (Arg1+ TAMs) inhibits tumor growth and concurrently reduces the ratio of TH1-Treg cells in the TME. Arg1+ TAMs secrete the chemokine platelet factor 4 (PF4), which reinforces interferon-γ (IFN-γ)-induced Treg cell polarization into TH1-Treg cells in a manner dependent on CXCR3 and the IFN-γ receptor. Both genetic PF4 inactivation and PF4 neutralization hinder TH1-Treg cell accumulation in the TME and reduce tumor growth. Collectively, our study highlights the importance of Arg1+ TAM-produced PF4 for high TH1-Treg cell levels in the TME to suppress antitumor immunity.

Mapping of the T Cell Landscape of Biliary Tract Cancer Unravels Anatomical Subtype-Specific Heterogeneity.

Biliary tract cancer (BTC), encompassing diseases such as intrahepatic (ICC), extrahepatic cholangiocarcinoma (ECC), and gallbladder cancer (GBC), is not only on the rise but also poses a significant and urgent health threat due to its high malignancy. Genomic differences point to the possibility that these subtypes represent distinct diseases. Elucidation of the specific distribution of T cell subsets, critical to cancer immunity, across these diseases could provide better insights into the unique biology of BTC subtypes and help identify potential precision medicine strategies. To address this, we conducted scRNA-seq and scTCR-seq on CD3+ T cells from 36 samples from 16 BTC patients across all subtypes and analyzed 355 pathological slides to examine the spatial distribution of T cells and tertiary lymphoid structures (TLS). Compared to ICC and GBC, ECC possessed a unique immune profile characterized by T cell exhaustion, elevated CXCL13 expression in CD4+ T helper-like and CD8+CXCL13+ exhausted T cells, more mature TLS, and fewer desert immunophenotypes. Conversely, ICC displayed an inflamed immunophenotype with an enrichment of interferon related pathways and high expression of LGALS1 in activated regulatory T cells, associated with immunosuppression. Inhibition of LGALS1 reduced tumor growth and Treg prevalence in ICC mouse models. Overall, this study unveils T cell diversity across BTC subtypes at the single-cell and spatial level that could open paths for tailored immunotherapies.

Novel Amanitin-based Antibody Drug Conjugates (ATAC®) targeting TROP2 for the treatment of Pancreatic Cancer.

Trophoblast cell surface antigen 2 (TROP2) exhibits aberrant expression in pancreatic cancer, correlating with metastasis, advanced tumor stage and poor prognosis of pancreatic ductal adenocarcinoma (PDAC) patients. TROP2 has been recognized as a promising therapeutic target for antibody drug conjugates (ADCs), as evidenced by the approval of the anti-TROP2 ADC Trodelvy® for the treatment of triple negative breast cancer. In this study we report the generation of novel second-generation amanitin based ADCs (ATAC®s) targeting TROP2, comprising the humanized RS7 antibody of Trodelvy® (hRS7) and the highly potent payload amanitin. The specific in vitro binding, efficient antigen internalization, and high cytotoxicity of hRS7 ATAC®s with half maximal effective concentration (EC50) values in the picomolar range in TROP2-expressing cells constituted the foundation for preclinical in vivo evaluation. The hRS7 ATAC®s demonstrated a significant reduction in tumor growth in vivo in subcutaneous xenograft mouse models of pancreatic cancer and triple negative breast cancer at well-tolerated doses. The antitumor efficacy correlated with the level of TROP2 expression on the tumors and the in vivo tumor uptake of the ATAC®s. The long half-life of 9.7-10.7 days of hRS7 ATAC®s without premature payload release in serum supported a high therapeutic index. Notably, the efficacy of the hRS7 ATAC®s was superior to that of Trodelvy® with complete tumor eradication in both, refractory pancreatic and triple negative breast cancer xenograft models. In summary, hRS7 ATAC®s represent a highly effective and well-tolerated targeted therapy, and our data support their development for pancreatic cancer and other TROP2-expressing tumors.

Development and Characterization of an Oncolytic Human Adenovirus-Based Vector Co-Expressing the Adenovirus Death Protein and p14 Fusion-Associated Small Transmembrane Fusogenic Protein.

Human adenovirus (HAdV)-based oncolytic vectors, which are designed to preferentially replicate in and kill cancer cells, have shown modest efficacy in human clinical trials in part due to poor viral distribution throughout the tumor mass. Previously, we showed that expression of the p14 fusion-associated small transmembrane (FAST) fusogenic protein could enhance oncolytic HAdV efficacy and reduce tumor growth rate in a human xenograft mouse model of cancer. We now explore whether co-expression of the adenovirus death protein (ADP) with p14 FAST protein could synergize to further enhance oncolytic vector efficacy. ADP is naturally encoded within the early region 3 (E3) of HAdV, a region which is frequently removed from HAdV-based vectors, and functions to enhance cell lysis and progeny release. We evaluated a variety of approaches to achieve optimal expression of the two proteins, the most efficient method being insertion of an expression cassette within the E3 deletion, consisting of the coding sequences for p14 FAST protein and ADP separated by a self-cleaving peptide derived from the porcine teschovirus-1 (P2A). However, the quantities of p14 FAST protein and ADP produced from this vector were reduced approximately 10-fold compared to a similar vector-expressing only p14 FAST protein and wildtype HAdV, respectively. Compared to our original oncolytic vector-expressing p14 FAST protein alone, reduced expression of p14 FAST protein and ADP from the P2A construct reduced cell-cell fusion, vector spread, and cell-killing activity in human A549 adenocarcinoma cells in culture. These studies show that a self-cleaving peptide can be used to express two different transgenes in an armed oncolytic HAdV vector, but also highlight the challenges in maintaining adequate transgene expression when modifying vector design.

Repurposing colforsin daropate to treat MYC-driven high-grade serous ovarian carcinomas.

High-grade serous ovarian cancer (HGSOC) is one of the deadliest cancers for women, with a low survival rate, no early detection biomarkers, a high rate of recurrence, and few therapeutic options. Forskolin, an activator of cyclic AMP signaling, has several anticancer activities, including against HGSOC, but has limited use in vivo. Its water-soluble derivative, colforsin daropate, has the same mechanism of action as forskolin and is used to treat acute heart failure. Here, we investigated the potential of colforsin daropate as a treatment for HGSOC. We found that colforsin daropate induced cell cycle arrest and apoptosis in cultured HGSOC cells and spheroids but had negligible cytotoxicity in immortalized, nontumorigenic fallopian tube secretory cells and ovarian surface epithelial cells. Colforsin daropate also prevented HGSOC cells from invading ovarian surface epithelial cell layers in culture. In vivo, colforsin daropate reduced tumor growth, synergized with cisplatin (a standard chemotherapy in ovarian cancer care), and improved host survival in subcutaneous and intraperitoneal xenograft models. These antitumor effects of colforsin daropate were mediated in part by its reduction in the abundance and transcriptional activity of the oncoprotein c-MYC, which is often increased in HGSOC. Our findings demonstrate that colforsin daropate may be a promising therapeutic that could be combined with conventional therapies to treat HGSOC.

Transcriptomics-Based Liquid Biopsy for Early Detection of Recurrence in Locally Advanced Gastric Cancer.

The study presents a transcriptomics-based liquid biopsy approach for early recurrence detection in locally advanced gastric cancer (LAGC). Four mRNA biomarkers (AGTR1, DNER, EPHA7, and SUSD5) linked to recurrence are identified through transcriptomic data analysis. A Risk Stratification Assessment (RSA) model combining these biomarkers with clinical features showed superior predictive accuracy for postoperative recurrence, with AUCs of 0.919 and 0.935 in surgical and liquid biopsy validation cohorts, respectively. Functional studies using human gastric cancer cell lines AGS and HGC-27 demonstrated that silencing the identified mRNA panel genes impaired cell migration, invasion, and proliferation. In vivo experiments further showed reduced tumor growth, metastasis, and lymphangiogenesis in mice, possibly mediated by the cAMP signaling pathway. This non-invasive approach offers significant potential for enhancing recurrence detection and enabling personalized treatment strategies, thereby improving patient outcomes in the management of LAGC.