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Da Wang,1,&ast; Chao Chen,1,&ast; Xiaoxu Ge,1,2 Qi Yang,2 Yuhuai Huang,1 Tianyi Ling,1 Tian Jin,1 Shaojun Yu,1 Jian Wang,1 Lifeng Sun1 1Department of Colorectal Surgery and Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People’s Republic of China; 2Department of Cancer Institute, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Da Wang; Lifeng SunDepartment of Colorectal Surgery and Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, People’s Republic of ChinaTel +86-571-87784720; +86-571-87783586Email wangda0618@zju.edu.cn; sunlifeng@zju.edu.cnPurpose: This study aimed to analyze clinicopathological, survival, prognostic factors, as well as the timing of brain metastases (BM) in colorectal cancer (CRC) using data from a Chinese center.Patients and Methods: Data of 65 consecutive CRC patients with BM were collected from a single institution in China. The time from primary tumor surgery to the occurrence of BM was calculated. Kaplan-Meier analysis was used to evaluate cumulative survival of patients. Factors associated with prognosis of overall survival (OS) were explored using Cox’s proportional hazard regression models.Results: The median time interval from CRC surgery to the diagnosis of BM was 24 months. After diagnosis of BM, median OS values for patients were 11 months. Extracranial metastases occurred in 45 cases (69.2%) when BM was diagnosed, and 58.5% of these patients with lung metastases Time of BMs (P=0.018), presence of extracranial metastases (P=0.033), treatment (P=0.003), CA199 (P=0.034), CA125 (P< 0.001), CA242 (P=0.018), and CA211 (P=0.012) were associated with OS of patients through univariate analysis. Multivariate analysis using a Cox regression model showed that only treatment was an independent predictor for OS (conservative treatment; HR=1.861, 95% CI=1.077– 3.441; P=0.048).Conclusion: Surgical treatment of metastatic lesions may be an alternative choice for CRC patients with BM. Identifying the timing of brain metastases can help to detect this disease early, leading to a better survival outcome.Keywords: colorectal cancer, brain metastases, prognosis factors, surgery

Background The transforming growth factor‐β (TGF‐β) pathway plays a pivotal role in inducing epithelial‐mesenchymal transition (EMT), which is a key step in cancer invasion and metastasis. However, the regulatory mechanism of TGF‐β in inducing EMT in colorectal cancer (CRC) has not been fully elucidated. In previous studies, it was found that S100A8 may regulate EMT. This study aimed to clarify the role of S100A8 in TGF‐β‐induced EMT and explore the underlying mechanism in CRC. Methods S100A8 and upstream transcription factor 2 (USF2) expression was detected by immunohistochemistry in 412 CRC tissues. Kaplan‐Meier survival analysis was performed. In vitro, Western blot, and migration and invasion assays were performed to investigate the effects of S100A8 and USF2 on TGF‐β‐induced EMT. Mouse metastasis models were used to determine in vivo metastasis ability. Luciferase reporter and chromatin immunoprecipitation assay were used to explore the role of USF2 on S100A8 transcription. Results During TGF‐β‐induced EMT in CRC cells, S100A8 and the transcription factor USF2 were upregulated. S100A8 promoted cell migration and invasion and EMT. USF2 transcriptionally regulated S100A8 expression by directly binding to its promoter region. Furthermore, TGF‐β enhanced the USF2/S100A8 signaling axis of CRC cells whereas extracellular S100A8 inhibited the USF2/S100A8 axis of CRC cells. S100A8 expression in tumor cells was associated with poor overall survival in CRC. USF2 expression was positively related to S100A8 expression in tumor cells but negatively related to S100A8‐positive stromal cells. Conclusions TGF‐β was found to promote EMT and metastasis through the USF2/S100A8 axis in CRC while extracellular S100A8 suppressed the USF2/S100A8 axis. USF2 was identified as an important switch on the intracellular and extracellular S100A8 feedback loop., In colorectal cancer, S100A8 in tumor cells predicts poor prognosis but that in stroma cells indicates good prognosis. We first proved that TGF‐β promotes metastasis through upregulated intracellular USF2/S100A8 axis, and USF2 maybe is the switcher on the opposite function of intracellular and extracellular S100A8.

Outcomes for patients with acute myeloid leukemia (AML) remain poor due to the inability of current therapies to fully eradicate disease initiating leukemia stem cells (LSCs) (Shlush et al., 2017). Many studies have demonstrated that LSCs have unique metabolic properties compared to AML blasts (Jones et al., 2021). However, the metabolite profiles of human LSCs and hematopoietic stem and progenitor cells (HSPCs) have not yet been directly compared. To examine metabolite levels in enriched LSCs and HSPCs we used mass spectrometry-based metabolomics analysis on enriched LSCs from 18 AML patients and HSPCs from 9 normal bone marrow (BM) specimens. Pathway analysis showed that arginine metabolism and biosynthesis were the most significantly enriched pathways in LSCs compared to HSPCs. Clinical studies have shown limited efficacy of targeting arginine levels using arginine degrading enzymes; therefore, we sought to target pathways downstream of arginine. Stable isotope labeled tracing analysis showed arginine was metabolized through the urea cycle into polyamines in human LSCs. Polyamines are cationic compounds which have been previously shown to be important for the growth of various cancers but their role in AML LSCs has yet to be determined. To investigate if polyamines are essential for LSC survival and function, we treated LSCs and HSPCs with N1,N11-diethylnorspermine (DENSpm), a polyamine analog causing polyamine depletion through increased cellular export. DENSpm treatment decreased the viability of LSCs and AML blasts in 10 out of 12 of patients tested but had no impact on HSPC viability. Further, treatment with DENSpm resulted in decreased engraftment potential of the 4 AML specimens examined in immune deficient mice but did not alter the engraftment of normal HSPCs, suggesting that targeting polyamines represents a promising approach to kill LSCs while sparing HSPCs. We then investigated the mechanisms regulated by polyamines in LSCs. Using RNA-sequencing analysis on enriched LSCs from 5 AML patients and HSPCs from 3 normal BM specimens we observed decreased expression of genes involved in protein synthesis in DENSpm-treated LSCs but not normal HSPCs. Protein synthesis and its regulation are critical for AML survival (Chen et al., 2019; Messling et al., 2022) but the role of polyamines in protein translation in LSCs has not been explored. Polyamines stimulate translation notably by serving as precursors for the hypusination of eukaryotic translation initiation factor 5A (eIF5A) (Park et al., 2010). Accordingly, DENSpm led to reduced protein synthesis level in MOLM13 AML cell line and primary AML samples. Strikingly, protein synthesis and viability were rescued upon co-treatment with spermidine, suggesting that DENSpm induces AML cells death at least in part through decreased eIF5A-mediated protein translation. Altogether, our data demonstrates that depletion of polyamines decreased LSC function while sparing normal HSPCs. Mechanistically, our data suggest that LSC targeting is accomplished through polyamine regulated protein synthesis. Citation Format: Vincent Rondeau, Cristiana O’Brien, Jacob M Berman, Duhan Yendi, Tianyi Ling, Aleksandra Bourdine, Aarushi Gupta, Jonathan St-Germain, Rachel Culp-Hill, Julie A Reisz, Soheil Jahangiri-Tazehkand, Anastasia Tikhonova, Andrea Arruda, Mark D Minden, Angelo D’Alessandro, Brian Raught, Courtney L Jones. Polyamines are required for AML LSC function through their role in regulating eIF5A dependent protein synthesis [abstract]. In: Proceedings of the AACR Special Conference: Acute Myeloid Leukemia and Myelodysplastic Syndrome; 2023 Jan 23-25; Austin, TX. Philadelphia (PA): AACR; Blood Cancer Discov 2023;4(3_Suppl):Abstract nr A54.

Acute myeloid leukemia (AML) is a devastating hematologic malignancy diagnosed in over 20,000 patients each year in the United States. The five-year survival rate in adult AML is less than 30%, highlighting the need for novel therapies to treat this malignancy. Current therapeutic approaches fail in part due of their inability to fully eradicate the disease-initiating leukemia stem cells (LSCs). Our previous work and the work of many others has demonstrated that LSCs have unique metabolic dependencies compared to the more differentiated AML blasts population. Importantly, these metabolic differences can be targeted to specifically eradicate the LSC population. To date, limited studies have examined the difference in metabolism between human LSCs and their normal counterparts, hematopoietic stem cells (HSCs), at the level of individual metabolites. To address this gap in our knowledge, we performed an unbiased mass spectrometry-based metabolomics analysis hematopoietic stem and progenitor cells (HSPCs) enriched from the bone marrow of 7 healthy donors and LSCs enriched from 18 primary AML patient specimens. This analysis revealed 38 metabolites that were significantly different between LSCs and HSPCs (FDR Citation Format: Vincent Rondeau, Rachel Culp-Hill, Cristiana O’Brien, Jacob Berman, Julie A. Reisz, Duhan Yendi, Tianyi Ling, Soheil Janangiri, Anastasia Tikhonova, Angelo D’Alessandro, Courtney Jones. Targeting polyamines metabolism in acute myeloid leukemia stem cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr NG07.

Atrial fibrillation (AF) is the most common cardiac arrhythmia. It tends to cause multiple cardiac conditions, such as cerebral artery blockage, stroke, and heart failure. The morbidity and mortality of AF have been progressively increasing over the past few decades, which has raised widespread concern about unobtrusive AF detection in routine life. The up-to-date non-invasive AF detection methods include electrocardiogram (ECG) signals and cardiac dynamics signals, such as the ballistocardiogram (BCG) signal, the seismocardiogram (SCG) signal and the photoplethysmogram (PPG) signal. Cardiac dynamics signals can be collected by cushions, mattresses, fabrics, or even cameras, which is more suitable for long-term monitoring. Therefore, methods for AF detection by cardiac dynamics signals bring about extensive attention for recent research. This paper reviews the current unobtrusive AF detection methods based on the three cardiac dynamics signals, summarized as data acquisition and preprocessing, feature extraction and selection, classification and diagnosis. In addition, the drawbacks and limitations of the existing methods are analyzed, and the challenges in future work are discussed.

Riboswitch, a part of regulatory mRNA (50–250nt in length), has two main classes: aptamer and expression platform. One of the main challenges raised during the classification of riboswitch is imbalanced data. That is a circumstance in which the records of a sequences of one group are very small compared to the others. Such circumstances lead classifier to ignore minority group and emphasize on majority ones, which results in a skewed classification. We considered sixteen riboswitch families, to be in accord with recent riboswitch classification work, that contain imbalanced sequences. The sequences were split into training and test set using a newly developed pipeline. From 5460 k-mers (k value 1 to 6) produced, 156 features were calculated based on CfsSubsetEval and BestFirst function found in WEKA 3.8. Statistically tested result was significantly difference between balanced and imbalanced sequences (p < 0.05). Besides, each algorithm also showed a significant difference in sensitivity, specificity, accuracy, and macro F-score when used in both groups (p < 0.05). Several k-mers clustered from heat map were discovered to have biological functions and motifs at the different positions like interior loops, terminal loops and helices. They were validated to have a biological function and some are riboswitch motifs. The analysis has discovered the importance of solving the challenges of majority bias analysis and overfitting. Presented results were generalized evaluation of both balanced and imbalanced models, which implies their ability of classifying, to classify novel riboswitches. The Python source code is available at https://github.com/Seasonsling/riboswitch., Author summary Machine learning application has been used in many ways in bioinformatics and computational biology. Its use in riboswitch classification is still limited. Existing attempts showed challenges due to imbalanced sequences. Algorithms can classify sequences with majority and minority groups, but they tend to ignore minority group and emphasize on majority class, consequential return a skewed classification. We used a new pipeline including SMOTE for balancing sequences that showed better-classified riboswitch as well as improved performance of algorithms selected. Statistically significant difference observed between balanced and imbalanced in sensitivity, specificity, accuracy and F-score, this proved balanced sequences better for classification of riboswitch. Biological functions and motif search of k-mers in riboswitch families revealed their presence in interior loops, terminal loops and helices. Some of the k-mers were reported to be riboswitch motifs of aptamer domains and critical for metabolite binding. The pipeline can be used in machine learning and deep learning study in other domains of bioinformatics and computational biology suffering from imbalanced sequences. Finally, scientific community can use python source code, the work done and flow to develop packages.

Acute myeloid leukemia (AML) in adults has a 5-year survival of approximately 30% and a high rate of disease recurrence in part due to our inability to eliminate the disease-initiating leukemic stem cells (LSCs) (Shlush et al. Nature, 2017). Previous studies have shown that LSCs uniquely rely on oxidative phosphorylation (OXPHOS) for survival (Lagadinou et al. Cell Stem Cell, 2013). Thus, novel therapies that are designed to target LSC metabolism have the potential to improve patient outcomes. Work from our group and others has demonstrated that a critical metabolite for OXPHOS regulation in LSCs is the coenzyme NAD + (Jones et al. Cell Stem Cell, 2020; Mitchell et al. Blood Advances 2019). One family of NAD + dependent proteins important in cancer biology, and AML specifically (Yan et al. Blood Cancer Discovery, 2021), are sirtuins. To determine if any sirtuins are important in LSC function we knocked down each sirtuin family member (sirtuin 1-7) with siRNA in four primary AML specimens and measured viability and colony forming ability. Knockdown of sirtuin 3 (SIRT3) decreased viability and colony forming potential of all AML specimens tested. SIRT3 is a mitochondrial de-acetylase with a multi-faceted role in metabolic regulation and oncogenesis (Finley, et al. Trends in Molecular Medicine, 2016). SIRT3 interacts with pathways upstream of OXPHOS including the tricarboxylic acid (TCA) and fatty acid oxidation (FAO). Importantly, a SIRT3 inhibitor (YC8-02) has been developed and has been shown to be effective pre-clinically for the treatment of B-cell lymphoma (Li et al. Cancer Cell, 2019). To further understand the significance of SIRT3 in LSCs, we assessed viability and colony forming potential upon YC8-02 treatment. LSCs were enriched from primary specimens based upon relative reactive oxygen species (ROS) level as previously described (Lagadinou et al. Cell Stem Cell, 2013). LSCs and blasts enriched from ten primary AML, and four AML cell lines (MOLM13, TEX, OCI-AML2, OCI-AML3) were cultured for 48 hours with or without YC8-02 before assessing viability and colony forming ability. YC8-02 treatment resulted in a significant decrease in colony forming potential of AML cells compared to control (data not shown). Similarly, LSCs, blasts, and cell lines showed a significant decrease in viability upon YC8-02 treatment (Fig 1A and data not shown). Cord blood and mobilized peripheral blood samples conversely did not show a change in colony forming potential following SIRT3 knockdown or YC8-02 treatment, respectively (data not shown). To assess YC8-02's effect on LSC function, three AML samples were treated with 10µM of drug for 24 hours and transplanted into NSG-S mice. YC8-02 treatment resulted in a significant decrease in AML engraftment, indicating a decrease in LSC function (Fig 1B). To determine the mechanism by which SIRT3 inhibition causes cell death, LSCs enriched from three primary specimens were treated with YC8-02; metabolite and lipid levels were determined by mass spectrometry. This analysis revealed a significant accumulation of fatty acids post YC8-02 treatment. To further characterize these changes, MOLM13 cells were treated with 13C 16-palmitic acid following 4 hours of incubation with 10µM YC8-02. Cells were collected 4 and 16 hours after introduction of palmitic acid and metabolic tracing was assessed by mass spectrometry. We found an accumulation of long and very long chain fatty acids and a decrease in TCA cycle intermediates (Fig 1C). FAO normally supplies TCA with intermediate acetyl-CoA; thus, these data indicate a decrease in FAO upon YC8-02 treatment. Accordingly, we measured changes in OXPHOS in response to treatment with YC8-02, in primary LSCs (Fig 1D) and AML cell lines (data not shown) and found a significant decrease in basal oxygen consumption. Further, ATP levels were significantly decreased upon YC8-02 treatment in LSCs (Fig 1E). In conclusion, we show that SIRT3 plays a pivotal role in FAO and LSC function. When SIRT3 is inhibited, FAO activity decreases resulting in the accumulation of long and very long chain fatty acids. This change in FAO activity reduces the availability of products for the TCA cycle, limiting necessary intermediates for OXPHOS, decreasing ATP production, and ultimately causing cell death. Therefore, our data suggests that SIRT3 is a potential therapeutic target for LSCs and should be considered in future pre-clinical and clinical investigations. Figure 1 Figure 1. Disclosures Melnick: Constellation: Consultancy; Epizyme: Consultancy; Daiichi Sankyo: Research Funding; Sanofi: Research Funding; Janssen Pharmaceuticals: Research Funding; KDAC Pharma: Membership on an entity's Board of Directors or advisory committees. Minden: Astellas: Consultancy. D'Alessandro: Omix Thecnologies: Other: Co-founder; Rubius Therapeutics: Consultancy; Forma Therapeutics: Membership on an entity's Board of Directors or advisory committees.