Neighboring Cells Research Articles

Abstract 6789: Development of an in vitro gastric cancer 3D co-culture platform using a microphysiological system (MPS) to improve outcomes in oncology clinical trials

Abstract Introduction: Despite significant advancements in scientific and diagnostic technologies, clinical trials for cancer often fail due to a lack of efficacy. Access to a platform that accurately predicts patient response is crucial to increase the success rate of clinical studies, and to minimize unnecessary exposure to ineffective and potentially harmful drug testing for patients. Because of the complexity of the disease, it would be beneficial to deploy patient samples for drug testing in a side-by-side comparison during the clinical trial. An accurate prediction of patient response earlier in the clinical study would aid decision making to determine the appropriate duration of treatment for each patient. Methods: We developed a 3D human cell co-culture model using our proprietary MPS technology, the Curio-spheroid Curiochip. Using patient samples isolated and expanded from either ascites fluids or biopsies to recapitulate the clinical phenotypes of advanced gastric cancer, we quantified the migratory properties of the patient cancer cells (i.e., the unique metastatic potential), and measured the level of secretion of VEGF. Somatic mutational analyses using NGS and RNAseq were performed for subtyping and clustering the samples. The patient cancer cells were expanded within 2 weeks post-collection, and used to form a spheroid that was loaded into a hydrogel embedded within the Curio-Spheroid, enabling the patient spheroids to interact through the hydrogel with neighboring (healthy) human endothelial cells. The patient spheroids induced aggressive vasculogenesis in the co-culture model, which was subdued by the anti-VEGFR2 antibody Ramucirumab. The platform was retrospectively validated with the Standard-of-Care (SOC) treatments that the patients received. Results: The patient cell testing took 3-4 weeks from sample collection to imaging. The patient cells preserved their migratory capacity, pro-angiogenic potential and drug responses in the vascularized model. The dose responses to SOC in the platform were consistent with the actual patient response assessments based on RECIST criteria, supporting the potential to use this platform to accurately predict patient clinical responses. Conclusions: The Curio-spheroid 3D co-culture model of vascularized gastric cancer provides a dynamic microenvironment to preserve the phenotypes of the patient cells and cell-cell interactions that are known to influence drug responses. This platform is compatible with high-throughput screening (HTS) for target or drug discovery with a good assay window. The ability to accurately recapitulate patient responses to SOC in the clinic make the Curio-Spheroid platform a promising method to test patient samples and measure drug responses of patients in real time during ongoing clinical trials. Citation Format: Yeongmin Choi, Sumin Kim, Youngsook Song, Yangji Kim, Jin Hawn Jang, Suryong Kim, Jihye Baek, Delaney Donnelly, Bushra Rajiput, Byungjun Lee, Woo Sun Kwon, Tsung-Li Liu, Kyusuk Baek, Sanghee Yoo, Sun Young Rha. Development of an in vitro gastric cancer 3D co-culture platform using a microphysiological system (MPS) to improve outcomes in oncology clinical trials [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 6789.

Abstract 2118: SGN-CEACAM5C/SAR445953, a novel topoisomerase I inhibitor antibody-drug conjugate targeting CEACAM5, has potent anti-tumor activity in CRC, PDAC, GC and lung cancer tumor models

Abstract Carcinoembryonic antigen cell adhesion molecule 5, CEACAM5, is a glycosylphosphatidylinositol-anchored glycoprotein expressed on the cell surface of most of the colorectal cancer (CRC) and pancreatic ductal adenocarcinoma (PDAC) and of more than 2/3 of gastric cancer (GC) and non-small cell lung cancer (NSCLC) while normal tissue expression is limited. The high prevalence of CEACAM5 expression prompted us to develop a novel CEACAM5 topoisomerase I inhibitor (Topo1i) antibody drug conjugate (ADC) with a DAR of 8, SGN-CEACAM5C/SAR445953. The anti-CEACAM5 antibody was chosen based on its high selectivity for CEACAM5 and its potential to direct cytotoxic payloads to tumor. The Topo1i payload was optimized for potency and enhanced bystander activity. SGN-CEACAM5C/SAR445953 is rapidly internalized and demonstrates in vitro cytotoxicity with EC50 values in the sub-nM range while it induces no toxicity on CEACAM5-negative cells. The potent anti-tumor activity is mediated by direct cytotoxicity on CEACAM5-expressing tumor cells and by a strong bystander effect due to the diffusion of the payload to the neighboring CEACAM5-negative tumor cells. Accordingly, the ADC incubated in a co-culture of CEACAM5-positive and -negative cells at a ratio of 1/1 induces a ~50% growth inhibition of CEACAM5-negative cells. Interestingly, with incubated ADC, only 1% of CEACAM5-positive cells in co-culture are sufficient to provide 11% growth inhibition of CEACAM5-negative cells. In vivo, SGN-CEACAM5C/SAR445953 is stable in circulation in SCID mice with a t1/2 close to 15 days. In vivo efficacy at 1, 3 and 10 mg/kg (single administration) was evaluated in panels of 4 CRC, 3 PDAC, 4 NSCLC and 3 GC patient-derived xenograft (PDX) models. At 10 mg/kg, the ADC elicits antitumor regression in 14/14 models. At 3 mg/kg, tumor regression occurs in 12/14 models. This potent, specific and dose dependent anti-tumor activity was further confirmed in Single Mouse Trials (SMT) of 20 CRC PDX models, 31 lung cancer PDX models and 19 gastric cancer PDX models. SMT consists in use of one animal per PDX model per treatment arm and for which the evaluation of efficacy is based on RECIST (Response Evaluation Criteria In Solid Tumors) criteria used in clinic. In CRC, gastric and lung cancer SMT, disease control rates are 95%, 84% and 87%, respectively with overall response rates of 55%, 68% and 71% including 15%, 10% and 26% of complete responses, respectively. The high anti-tumor activity across panels of PDX models of several CEACAM5 positive indications supports further evaluation of SGN-CEACAM5C/SAR445953 in patients with CRC, PDAC, GC and lung cancers (NCT06131840). Citation Format: Yves Baudat, Celine Nicolazzi, Johann Petur Sigurjonsson, Celine Amara, Astrid Clarke, Ryan lyski, Dave Meyer, Valeria Fantin, Marielle Chiron, Stephanie Decary. SGN-CEACAM5C/SAR445953, a novel topoisomerase I inhibitor antibody-drug conjugate targeting CEACAM5, has potent anti-tumor activity in CRC, PDAC, GC and lung cancer tumor models [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 2118.

Abstract 4700: Induced phenotype targeted ADC by using caspase enzymatic cleavable peptide linker to overcome tumor heterogeneity

Abstract Antibody-drug conjugates (ADCs) have ushered in a new era of precision cancer therapy, and the caspase-3-cleavable linker has demonstrated its potential as a game-changing addition to the ADC toolkit. The DEVD peptide, specifically cleaved by caspase and lysosomal enzymes, in combination with the KG peptide, provides the necessary flexibility to achieve targeted cancer cell apoptosis. This research explores the key attributes and actions of the linker, aiming to highlight its potential for revolutionizing ADC therapy. The caspase-3-cleavable linker operates through caspase-3 activation during apoptosis. After targeting cancer cells with specific antigens, the ADC is internalized into the cells, and the linker is cleaved by caspase-3, releasing the drug and initiating apoptosis. The specificity of caspase-3 extends the drug’s effect to neighboring cells, even those lacking the target antigen. This cascade effect ensures the continuous activation of ADCs until all cancer cells are eradicated. Firstly, it overcomes tumor heterogeneity by activating the drug outside of the cell. Traditional bystander killing effects rely on internalization followed by drug release and penetration of neighbor cancer cells. However, this linker's unique mechanism ensures that the drug is activated by caspase-3 outside the cell without the need for internalization, effectively targeting all cancer cells within the tumor tissue. This is achieved through the induced phenotype targeting effect (IPTE), which involves caspase-3 cleavage of the linker, inducing a phenotype in the tumor tissue that targets all cancer cells, regardless of their specific markers. Secondly, it maintains therapeutic efficacy even as the target antigen decreases. Current targeted therapies face a challenge as target antigens may diminish during treatment, leading to reduced drug effectiveness. However, the unique mechanism of the linker ensures that the drug continues to be activated as long as there is caspase-3 secretion, resulting in continuous activation of ADCs in the tumor, with a feedback amplification loop that ensures therapeutic efficacy until all cancer cells are eliminated. Lastly, the linker's superior physicochemical properties allow for a maximum drug-to-antibody ratio (DAR). Its hydrophilic nature enables independent drug conjugation, increasing therapeutic potential and mitigating aggregation issues. This innovation addresses the current limitations in ADC conjugation technologies. In summary, the caspase-3-cleavable linker represents a significant leap forward in the field of ADCs. Its unique attributes offer promising prospects for more effective and targeted cancer treatments. This linker is poised to revolutionize the landscape of targeted cancer therapy, bringing us one step closer to the dream of eradicating cancer cells with precision and efficiency. Citation Format: Ha Kyeong Lee, Byoungmo Kim, Hyo Won Chang, Sang Yoon Kim, Youngro Byun. Induced phenotype targeted ADC by using caspase enzymatic cleavable peptide linker to overcome tumor heterogeneity [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 4700.

Abstract 3452: Senescence-associated secretory phenotype (SASP) aging index is associated with cancer risk in the Atherosclerosis Risk in Communities (ARIC) Study

Abstract Background: The accumulation of senescent cells, which release SASP proteins damaging neighboring cells, contributes to aging and age-related diseases, such as cancer. Therefore, SASP proteins could be used as biomarkers for individuals’ aging process, but no studies have tested if SASP protein-based aging index is associated with cancer risk. We created a SASP-aging index based on the 72 SASP proteins reported in Tanaka et al. [2018] and examined its association with cancer risk in the ARIC study. Methods: ARIC is an ongoing cohort of White and Black females and males initiated in 1987, followed for cancer until 2015 (median follow-up=17.3 yrs). At Visit 2 (1990-92), 5000 plasma proteins were measured using SomaScan – an aptamer-based assay in 10,834 participants (aged 46-70 yrs, 55% female, 76% White): 3,347 participants developed cancer during follow-up and 7,487 participants stayed cancer-free. In the training set of 67% randomly selected cancer-free participants, we constructed the SASP-aging index by applying Ridge regression to train the 72 SASP proteins against chronological age. The SASP-aging index was validated in the remaining 33% of cancer-free participants (test set). We calculated age acceleration as residuals after regressing the SASP-aging index on age in participants after excluding the training set. We used Cox proportional hazards regression to estimate hazard ratio (HR) and 95% confidence intervals (CI) for the risk of any type of cancer per 5 years increase in age acceleration, employing Barlow’s method [1994] to account for the exclusion of the training set. HR was adjusted for age, sex, race, center, education, BMI, smoking status, alcohol intake, aspirin use, diabetes, and eGFR. We also estimated HRs for obesity-related, smoking-related, and the most common cancers (breast, prostate, colorectal, and lung). Results: In the test set, Pearson correlation coefficient between the SASP-aging index and age was 0.50. Age acceleration was significantly associated with the risk of any type of cancer [HR (95% CI) per 5 years=1.21 (1.08-1.36)]. There was a suggestion of a higher HR for any type of cancer in females [1.26 (1.07-1.48)] than males [1.18 (1.00-1.39)] [p-interaction=0.08], but HRs were similar across race and smoking status [p-interaction>0.50]. Age acceleration was significantly associated with the risk of obesity-related cancers [1.36 (1.20-1.54)]. A significant association was also found with smoking-related cancers [1.43 (1.24-1.65)] and this association remained significant even among never smokers [1.39 (1.07- 1.82)]. Age acceleration was also significantly associated with colorectal [1.34 (1.03-1.75)] and lung cancer risk [1.63 (1.31-2.02)] but not with breast or prostate cancer risk. Conclusion: SASP protein-based aging index shows promise as a potential biomarker for cancer risk. Funding: NHLBI, NCI, NPCR Citation Format: Shuo Wang, Zexi Rao, Anne H. Blaes, Josef Coresh, Corinne E. Joshu, James S. Pankow, Bharat Thyagarajan, Peter Ganz, Elizabeth A. Platz, Weihua Guan, Anna Prizment. Senescence-associated secretory phenotype (SASP) aging index is associated with cancer risk in the Atherosclerosis Risk in Communities (ARIC) Study [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 3452.

Abstract 1152: Pan-cancer single-cell and subcellular characterization of lymphoid aggregates and tertiary lymphoid structures using high-plex spatial molecular imaging

Abstract Tertiary lymphoid structures (TLSs), clusters of immune cells that form in non-lymphoid tissues, are frequently identified in a wide range of solid tumors. They function as immunological “hubs”, driving anti-tumor responses. Previous studies have demonstrated that the presence of TLSs is often associated with improved responses to immunotherapy and superior clinical outcomes. Despite these insights, our understanding of their phenotypic diversity, spatial organization, intercellular communication, and interactions with cancer cells and the tumor microenvironment remains incomplete. Existing methods lack the resolution, depth, and scale required for a thorough understanding of these complex structures. We have obtained in-house and public spatial multi-omics data generated on various tissues across 9 different cancer types using the cutting-edge single-cell spatial transcriptomics and high-plex spatial molecular imaging platforms. We have developed innovative computational approaches for the detailed characterization of TLSs at single-cell and subcellular resolution and carried out an extensive analysis of lymphoid aggregates (LAs) and TLSs in tissue sections across these different solid cancer types. We defined the phenotypic state of each individual cell within TLSs including B/plasma cells, follicular helper/regulatory/stressed/exhausted T cells, follicular dendritic cells, fibroblasts and high endothelial venules. Then, we performed unbiased phenotyping and classification of TLSs based on their cellular states, compositions and organization patterns across various types of tissues. Additionally, we performed spatial neighborhood analysis, characterized the neighboring cells of each TLS and analyzed their cell-cell communication networks. Our approach allowed an unprecedented examination of the spatial phenotypes of TLSs in large, complex tissues at super resolution, in ways that were not previously described. We comprehensively characterized TLSs across different solid tumor types. Our analysis revealed a high degree of spatial and phenotypic heterogeneity in LAs and TLSs. We created a comprehensive spatial atlas of LAs and TLSs across solid tumor types, profiled TLSs at various maturation states with distinct cellular composition and organization patterns, and discovered new TLS states. Notably, we observed distinct communication networks associated with TLS phenotypic states. Our innovative methods and analytical approaches offer a more comprehensive way to study LAs and TLSs, enhancing detection capabilities and providing deeper insights into their spatial interaction and functional phenotypes. This research holds the potential to significantly advance our understanding of TLSs and their roles in immunobiology and immunotherapy responses across a broad range of cancers and diseases. Citation Format: Yunhe Liu, Yuanyuan Zhang, Guangchun Han, Guangsheng Pei, Kyung Serk Cho, Enyu Dai, Yanshuo Chu, Jiahui Jiang, Ansam Sinjab, Luisa M. Soto, Alejandra Serrano, Jianjun Gao, Humam Kadara, Catherine Fridman, Wolf Herve Fridman, Linghua Wang. Pan-cancer single-cell and subcellular characterization of lymphoid aggregates and tertiary lymphoid structures using high-plex spatial molecular imaging [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 1152.

Abstract 2962: Chemotherapy induced senescence drives peripheral neuropathy

Abstract Chemotherapy is a mainstay of cancer therapy. Unfortunately, while chemotherapy can profoundly impact disease free survival, it is often accompanied with devastating side effects including hair loss, bone loss, cognitive impairment (referred to as "brain fog"), and peripheral neuropathies. While many of these side effects may subside after the completion of chemotherapy, some persist for a lifetime, substantially compromising the quality of life for survivors. Particularly insidious is chemotherapy-induced peripheral neuropathy (CIPN), which can impair a patient's ability to care for themselves. Shockingly, in over 30% of patients, CIPN persists even after the cessation of chemotherapy, subjecting them to a lifetime of numbness and/or pain. Paclitaxel (PTX), a common treatment for breast cancer, induces CIPN in 61-92% of patients depending on the administered dose. Unfortunately, there are currently no preventative or curative measures for CIPN resulting in side effects that persist for months or even years after the cessation of chemotherapy. Considering chemotherapy can trigger cellular senescence, leading to the release of a diverse array of factors collectively known as the senescence-associated secretory phenotype (SASP) that are capable of negatively influencing neighboring cells. To determine if senescence played a role in CIPN we treated with PTX and found that animals displayed reduced axon innervation in the paws and diminished paw withdrawal responses during the von Frey assay, characteristic symptoms of CIPN. To determine if senescent drove PTX-induced CIPN, we utilized the INKATTAC (INK) mouse, a model in which a p16INK4a promoter drives an inducible suicide transgene to eliminate p16+ senescent cells following treatment with AP20187 (AP). Employing the INK mouse, we successfully prevented CIPN by eliminating PTX-induced senescent cells. Furthermore, through bone marrow (BM) transplant studies using BM from INK mice into wildtype recipients, we failed to prevent CIPN. This result establishes that senescent immune cells, do not contribute to CIPN. In an independent approach, we found that senolytic drugs (kill senescent cells), such as dasatinib and quercetin (DQ) or ABT737 (ABT), effectively prevented and reversed CIPN in mice. Additionally, since the p38MAPK pathway has been shown to regulate SASP mRNA stability, we treated with p38 and MK2 inhibitors and found that inhibition prevented CIPN in mice. To address the mechanism behind CIPN we have carried out single cell RNA sequencing (scRNA-seq) to identify the cell population senescing in response to chemotherapy. These analyses will allow us to understand the mechanisms that drive CIPN and may lead to new treatments for patients suffering from CIPN. Citation Format: Taylor Malachowski, Ganesh Kumar Raut, Xianmin Luo, Satarupa Mullick Bagchi, Sheila Stewart. Chemotherapy induced senescence drives peripheral neuropathy [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 2962.

Abstract 1901: Disitamab vedotin, a clinical stage HER2-directed antibody-drug conjugate, shows potent antitumor activity as a monotherapy in preclinical urothelial cancer models

Abstract Disitamab vedotin (DV, RC48-ADC) is an antibody-drug conjugate (ADC) that selectively delivers cytotoxic drug to HER2-expressing cancer cells. DV is composed of disitamab, a HER2-directed monoclonal antibody, and a vedotin linker-payload system, which enables conjugation of the microtubule-disrupting agent monomethyl auristatin E (MMAE) to the antibody via a protease-cleavable linker. The proposed mechanism of action (MOA) of DV occurs through direct cytotoxicity of HER2-expressing tumor cells following internalization of DV and intracellular release of MMAE. DV may also induce antitumor activity through bystander-mediated cytotoxicity of neighboring cells and via the inhibition of HER2 signaling pathways. Moreover, cellular response to MMAE includes the induction of immunogenic cell death and recruitment of immune cells to the tumor site. DV is currently being evaluated globally in subjects with HER2-expressing locally advanced or metastatic urothelial carcinoma (la/mUC) and has gained conditional approval in China following an overall response rate of 50.5% (pooled analysis from studies NCT03507166 and NCT03809013). RNA sequencing data from a large cohort of urothelial cancer patient tumors revealed expression of HER2 in many urothelial tumors; however, the relationship between HER2 expression and efficacy of DV is not well understood. Here, we sought to evaluate the antitumor activity of DV monotherapy in preclinical urothelial cancer models with varying levels of HER2 expression. Multiple patient-derived xenografts (PDX) and patient-derived 3D in vitro urothelial cancer models showed potent antitumor response to DV monotherapy in tumors with varying HER2 expression levels including HER2-low tumors. Overall, these findings support ongoing clinical trials in subjects with HER2-expressing la/mUC and provide scientific rationale to further explore DV monotherapy in HER2-positive and HER2-low urothelial cancer clinical settings. Citation Format: Renee Hein, Kelsi Willis, Gina LoMastro, Suhas Vasaikar, Vinita Gupta, Katie Snead, Sharsti Sandall, Anita Kulukian. Disitamab vedotin, a clinical stage HER2-directed antibody-drug conjugate, shows potent antitumor activity as a monotherapy in preclinical urothelial cancer models [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 1901.

Abstract 4265: ZEB1-regulated hyaluronan network in the lung tumor microenvironment

Abstract In the tumor microenvironment, hyaluronan surrounds neighboring cells as one of the major components of the extracellular matrix and stimulates the epithelial-mesenchymal transition (EMT) of various epithelial cancer cells. However, the mechanism of how the hyaluronic network is formed by cancer cells and regulates cancer progression and metastasis has not been known in detail. Therefore, we investigated the role of the hyaluronan network built-up by cancer cells in regulating cancer progression and metastasis in the tumor microenvironment. Our study demonstrated that ZEB1, an EMT-inducing transcription factor, reconstructs the hyaluronan network to induce the expression of ITIH2, a hyaluronan-binding protein, and hyaluronic acid synthase-2 (HAS2), ZEB1 was also shown to control the isoform switching of CD44, a hyaluronan receptor. ITIH2 knockdown and HAS inhibition reduced the formation of hyaluronan cables and inhibited cancer cell migration and invasion. In addition, the treatment of a specific ITIH2 inhibitor identified through deep learning-based screening suppressed the formation of hyaluronan cables, cell migration, and metastasis. These findings suggest that targeting the hyaluronan network could be a novel strategy for suppressing lung cancer progression and metastasis in the tumor microenvironment. Citation Format: Sieun Lee, Jihye Park, Eun Ju Kim, Seongran Cho, Sungsoo Park, Jonathan M Kurie, Young-Ho Ahn. ZEB1-regulated hyaluronan network in the lung tumor microenvironment [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 4265.

Gene transfer agents: The ambiguous role of selfless viruses in genetic exchange and bacterial evolution.

Gene transfer agents (GTAs) are genetic elements derived from ancestral bacteriophages that have become domesticated by the host. GTAs are present in diverse prokaryotic organisms, where they can facilitate horizontal gene transfer under certain conditions. Unlike typical bacteriophages, GTAs do not exhibit any preference for the replication or transfer of the genes encoding them; instead, they exhibit a remarkable capacity to package chromosomal, and sometimes extrachromosomal, DNA into virus-like capsids and disseminate it to neighboring cells. Because GTAs resemble defective prophages, identification of novel GTAs is not trivial. The detection of candidates relies on the genetic similarity to known GTAs, which has been fruitful in α-proteobacterial lineages but challenging in more distant bacteria. Here we consider several fundamental questions: What is the true prevalence of GTAs in prokaryote genomes? Given there are high costs for GTA production, what advantage do GTAs provide to the bacterial host to justify their maintenance? How is the bacterial chromosome recognized and processed for inclusion in GTA particles? This article highlights the challenges in comprehensively understanding GTAs' prevalence, function and DNA packaging method. Going forward, broad study of atypical GTAs and use of ecologically relevant conditions are required to uncover their true impact on bacterial chromosome evolution.

Brain Tumor Detection based on Multiple Deep Learning Models for MRI Images

INTRODUCTION: Medical imaging techniques are used to analyze the inner workings of the human body. In today's scientific world, medical image analysis is the most demanding and rising discipline, with brain tumor being the most deadly and destructive kind of malignancy. A brain tumor is an abnormal growth of cells within the skull that disrupts normal brain function by damaging neighboring cells. Brain tumors are regarded as one of the most dangerous, visible, and potentially fatal illnesses in the world. Because of the fast proliferation of tumor cells, brain tumors kill thousands of people each year all over the world. To save the lives of thousands of individuals worldwide, prompt analysis and automated identification of brain tumors are essential.
 OBJECTIVES: To design a enhanced deep learning model for brain tumor detection and classification from MRI analysis.
 METHODS: The proposed models Densenet-121, Resnet-101 Mobilenet-V2 is used to perform the task of Brain tumor detection for multi- class classification.
 RESULTS: The proposed models achieved an accuracy of up to 99% in our evaluations, and when compared to competing models, they yield superior results.
 CONCLUSION: The MRI image collection has been used to train deep learning models. The experimental findings show that the Densnet-121 model delivers the highest accuracy (99%) compared to other models. The system will have significant applications in the medical field. The presence or absence of a tumour can be ascertained using the proposed method.

Design guidelines to prevent thermal propagation and maximize packing density within battery systems with tabless cylindrical lithium-ion cells

Large-format tabless cylindrical lithium-ion cells are a promising candidate to not only enhance performance and reduce cost of next generation vehicles but also increase safety compared to other cell formats. In this study, numerical models are developed and validated based on sophisticated mass-produced large-format tabless cylindrical cells that allow analyzing the thermal propagation resilience. Experiments are conducted to prove cylindrical cells may locally drastically exceed common trigger temperatures obtained from accelerating rate calorimetry. A thermal propagation risk map is introduced that establishes an understanding on the influence of the convective and conductive heat paths on different timescales. The influence of varying dimensions and housing materials is revealed and the minimal cell-to-cell spacing is determined that maximizes packing density while still obeying strict no-thermal propagation philosophy. Results show great emphasize must be put on design measures to prevent hot venting gas to introduce heat into the neighboring cells through convection. Afterwards, the cells mass loss and spacing should be optimized to counter the leftover conductive heat path and optimize packing density. The larger the diameter, the further the cells need to be positioned apart. Cells with aluminum housing require less spacing and enable tighter packing density compared to regular deep-drawn steel housings due to the ability to dissipate heat in circumferential and axial direction away from the critical area with highest active material temperatures.

Gap junctions in polycystic ovary syndrome: Implications for follicular arrest.

Gap junctions are specialized intercellular conduits that provide a direct pathway between neighboring cells, which are involved in numerous physiological processes, such as cellular differentiation, cell growth, and metabolic coordination. The effect of gap junctional hemichannels in folliculogenesis is particularly obvious, and the down-regulation of connexins is related to abnormal follicle growth. Polycystic ovary syndrome (PCOS) is a ubiquitous endocrine disorder of the reproductive system, affecting the fertility of adult women due to anovulation. Exciting evidence shows that gap junction is involved in the pathological process related to PCOS and affects the development of follicles in women with PCOS. In this review, we examine the expression of connexins in follicular cells of PCOS and figure out whether such communication could have consequences for PCOS women. While along with results from clinical and related animal studies, we summarize the mechanism of connexins involved in the pathogenesis of PCOS.

Manipulating the physical distance between cells during soil colonization reveals the importance of biotic interactions in microbial community assembly

BackgroundMicrobial communities are of tremendous importance for ecosystem functioning and yet we know little about the ecological processes driving the assembly of these communities in the environment. Here, we used an unprecedented experimental approach based on the manipulation of physical distance between neighboring cells during soil colonization to determine the role of bacterial interactions in soil community assembly. We hypothesized that experimentally manipulating the physical distance between bacterial cells will modify the interaction strengths leading to differences in microbial community composition, with increasing distance between neighbors favoring poor competitors.ResultsWe found significant differences in both bacterial community diversity, composition and co-occurrence networks after soil colonization that were related to physical distancing. We show that reducing distances between cells resulted in a loss of bacterial diversity, with at least 41% of the dominant OTUs being significantly affected by physical distancing. Our results suggest that physical distancing may differentially modulate competitiveness between neighboring species depending on the taxa present in the community. The mixing of communities that assembled at high and low cell densities did not reveal any “home field advantage” during coalescence. This confirms that the observed differences in competitiveness were due to biotic rather than abiotic filtering.ConclusionsOur study demonstrates that the competitiveness of bacteria strongly depends on cell density and community membership, therefore highlighting the fundamental role of microbial interactions in the assembly of soil communities.

Polyamine-mediated ferroptosis amplification acts as a targetable vulnerability in cancer

Targeting ferroptosis, an iron-dependent form of regulated cell death triggered by the lethal overload of lipid peroxides, in cancer therapy is impeded by our limited understanding of the intersection of tumour’s metabolic feature and ferroptosis vulnerability. In the present study, arginine is identified as a ferroptotic promoter using a metabolites library. This effect is mainly achieved through arginine’s conversion to polyamines, which exerts their potent ferroptosis-promoting property in an H2O2-dependent manner. Notably, the expression of ornithine decarboxylase 1 (ODC1), the critical enzyme catalysing polyamine synthesis, is significantly activated by the ferroptosis signal——iron overload——through WNT/MYC signalling, as well as the subsequent elevated polyamine synthesis, thus forming a ferroptosis-iron overload-WNT/MYC-ODC1-polyamine-H2O2 positive feedback loop that amplifies ferroptosis. Meanwhile, we notice that ferroptotic cells release enhanced polyamine-containing extracellular vesicles into the microenvironment, thereby further sensitizing neighbouring cells to ferroptosis and accelerating the “spread” of ferroptosis in the tumour region. Besides, polyamine supplementation also sensitizes cancer cells or xenograft tumours to radiotherapy or chemotherapy through inducing ferroptosis. Considering that cancer cells are often characterized by elevated intracellular polyamine pools, our results indicate that polyamine metabolism exposes a targetable vulnerability to ferroptosis and represents an exciting opportunity for therapeutic strategies for cancer.

Type 1 fimbriae-mediated collective protection against type 6 secretion system attacks.

Bacterial competition may rely on secretion systems such as the type 6 secretion system (T6SS), which punctures and releases toxic molecules into neighboring cells. To subsist, bacterial targets must counteract the threats posed by T6SS-positive competitors. In this study, we used a comprehensive genome-wide high-throughput screening approach to investigate the dynamics of interbacterial competition. Our primary goal was to identify deletion mutants within the well-characterized E. coli K-12 single-gene deletion library, the Keio collection, that demonstrated resistance to T6SS-mediated killing by the enteropathogenic bacterium Cronobacter malonaticus. We identified 49 potential mutants conferring resistance to T6SS and focused our interest on a deletion mutant (∆fimE) exhibiting enhanced expression of type 1 fimbriae. We demonstrated that the presence of type 1 fimbriae leads to the formation of microcolonies and thus protects against T6SS-mediated assaults. Collectively, our study demonstrated that adhesive structures such as type 1 fimbriae confer collective protective behavior against T6SS attacks.IMPORTANCEType 6 secretion systems (T6SS) are molecular weapons employed by gram-negative bacteria to eliminate neighboring microbes. T6SS plays a pivotal role as a virulence factor, enabling pathogenic gram-negative bacteria to compete with the established communities to colonize hosts and induce infections. Gaining a deeper understanding of bacterial interactions will allow the development of strategies to control the action of systems such as the T6SS that can manipulate bacterial communities. In this context, we demonstrate that bacteria targeted by T6SS attacks from the enteric pathogen Cronobacter malonaticus, which poses a significant threat to infants, can develop a collective protective mechanism centered on the production of type I fimbriae. These adhesive structures promote the aggregation of bacterial preys and the formation of microcolonies, which protect the cells from T6SS attacks.

TNFRSF1B Signaling Blockade Protects Airway Epithelial Cells from Oxidative Stress.

Progressive respiratory airway destruction due to unresolved inflammation induced by periodic infectious exacerbation episodes is a hallmark of cystic fibrosis (CF) lung pathology. To clear bacteria, neutrophils release high amounts of reactive oxygen species (ROS), which inflict collateral damage to the neighboring epithelial cells causing oxidative stress. A former genome-wide small interfering RNA (siRNA) screening in CF submucosal gland cells, instrumental for mucociliary clearance, proposed tumor necrosis factor receptor superfamily member 1B (TNFRSF1B; TNFR2) as a potential hit involved in oxidative stress susceptibility. Here, we demonstrate the relevance of TNFRSF1B transcript knock-down for epithelial cell protection under strong oxidative stress conditions. Moreover, a blockade of TNFR signaling through its ligand lymphotoxin-α (LTA), overexpressed in airway epithelial cells under oxidative stress conditions, using the anti-tumor necrosis factor (TNF) biologic etanercept significantly increased the viability of these cells from a toxic oxidizing agent. Furthermore, bioinformatic analyses considering our previous RNA interference (RNAi) screening output highlight the relevance of TNFRSF1B and of other genes within the TNF pathway leading to epithelial cell death. Thus, the inhibition of the LTα3-TNFR2 axis could represent a useful therapeutic strategy to protect the respiratory airway epithelial lining from the oxidative stress challenge because of recurrent infection/inflammation cycles faced by CF patients.

P53 and BCL-2 family proteins PUMA and NOXA define competitive fitness in pluripotent cell competition.

Cell Competition is a process by which neighboring cells compare their fitness. As a result, viable but suboptimal cells are selectively eliminated in the presence of fitter cells. In the early mammalian embryo, epiblast pluripotent cells undergo extensive Cell Competition, which prevents suboptimal cells from contributing to the newly forming organism. While competitive ability is regulated by MYC in the epiblast, the mechanisms that contribute to competitive fitness in this context are largely unknown. Here, we report that P53 and its pro-apoptotic targets PUMA and NOXA regulate apoptosis susceptibility and competitive fitness in pluripotent cells. PUMA is widely expressed specifically in pluripotent cells in vitro and in vivo. We found that P53 regulates MYC levels in pluripotent cells, which connects these two Cell Competition pathways, however, MYC and PUMA/NOXA levels are independently regulated by P53. We propose a model that integrates a bifurcated P53 pathway regulating both MYC and PUMA/NOXA levels and determines competitive fitness.

An Improved Interference Mitigation Scheme for Femtocell Networks

Femtocell networks have gained significant attention in recent years due to their ability to improve indoor wireless coverage and capacity. However, they are susceptible to interference from neighboring cells, which significantly degrade their performance and quality of service to the end-user. The study introduced an adaptive power control technique that causes the power level of the femtocell base station to adjust dynamically to reduce the interference caused by adjacent femtocell networks, thereby adjusting the system bandwidth, carrier frequency, path loss and femtocell Base Station (BS) transmission power based on the request made by the users. The interference mitigation scheme was optimized by tuning the parameters of the power control algorithm, such as the transmit power levels and the interference thresholds. The algorithm was simulated with MATLAB simulation tools. Throughput, Signal to Interference Noise Ratio (SINR), coverage enhancement and user satisfaction were used as measurement metrics for the model using descriptive statistics. The results showed that the average performance obtained for the throughput increased by 25.88% from 3.40 X 1010 (bps) to 4.28 X 1010 (bps), and the SINR increased by 35.29% from 1.70 X 109 dB to 2.30 X109 dB for the benchmarked power control and improved power control techniques respectively. Coverage enhancement and user satisfaction were nearly 0, which indicates that the technique was of average performance. This study concluded that the new scheme enhances wider coverage to reach more users and mitigate interference while maintaining a higher level of femtocell user satisfaction.

Using embryo models to understand the development and progression of embryonic lineages: a focus on primordial germ cell development.

Recapitulating mammalian cell type differentiation in vitro promises to improve our understanding of how these processes happen in vivo, while bringing additional prospects for biomedical applications. The establishment of stem cell-derived embryo models and embryonic organoids, which have experienced explosive growth over the last few years, open new avenues for research due to their scale, reproducibility, and accessibility. Embryo models mimic various developmental stages, exhibit different degrees of complexity, and can be established across species. Since embryo models exhibit multiple lineages organised spatially and temporally, they are likely to provide cellular niches that, to some degree, recapitulate the embryonic setting and enable "co-development" between cell types and neighbouring populations. One example where this is already apparent is in the case of primordial germ cell-like cells (PGCLCs). While directed differentiation protocols enable the efficient generation of high PGCLC numbers, embryo models provide an attractive alternative as they enable the study of interactions of PGCLCs with neighbouring cells, alongside the regulatory molecular and biophysical mechanisms of PGC competency. Additionally, some embryo models can recapitulate post-specification stages of PGC development (including migration or gametogenesis), mimicking the inductive signals pushing PGCLCs to mature and differentiate, and enabling the study of PGCLC development across stages. Therefore, in vitro models may allow us to address questions of cell type differentiation, and PGC development specifically, that have hitherto been out of reach with existing systems. This review evaluates the current advances in stem cell-based embryo models, with a focus on their potential to model cell type-specific differentiation in general, and in particular to address open questions in PGC development and gametogenesis.

Cancer-associated fibroblasts produce matrix-bound vesicles that influence endothelial cell function.

Intercellular communication between different cell types in solid tumors contributes to tumor growth and metastatic dissemination. The secretome of cancer-associated fibroblasts (CAFs) plays major roles in these processes. Using human mammary CAFs, we showed that CAFs with a myofibroblast phenotype released extracellular vesicles that transferred proteins to endothelial cells (ECs) that affected their interaction with immune cells. Mass spectrometry-based proteomics identified proteins transferred from CAFs to ECs, which included plasma membrane receptors. Using THY1 as an example of a transferred plasma membrane-bound protein, we showed that CAF-derived proteins increased the adhesion of a monocyte cell line to ECs. CAFs produced high amounts of matrix-bound EVs, which were the primary vehicles of protein transfer. Hence, our work paves the way for future studies that investigate how CAF-derived matrix-bound EVs influence tumor pathology by regulating the function of neighboring cancer, stromal, and immune cells.