Hypothesis: hematogenous metastatic cancer cells of solid tumors may disguise themselves as memory macrophages for metastasis.

German pathologist Otto Aichel suggested, a century ago, that the cancer cell acquired its metastatic property from a leukocyte via cell-cell fusion. Since then, several revised versions of this theory have been proposed. Most of the proposals attribute the generation of the metastatic cancer cell to the fusion between a primary cancer cell and a macrophage. However, these theories have not addressed several issues, such as dormancy and stem cell-like self-renewal, of the metastatic cancer cell. On the other hand, recent studies have found that, like T- and B-/plasma cells, macrophages can also be categorized into naïve, effector, and memory/trained macrophages. As a memory/trained macrophage can enter dormancy/quiescence, be awakened from the dormancy/quiescence by acquainted primers, and re-populate via stem cell-like self-renewal, we, therefore, further specify that the macrophage fusing with the cancer cell and contributing to metastasis, belongs with the memory/trained macrophage, not other subtypes of macrophages. The current theory can explain many puzzling clinical features of cancer, including the paradoxal effects (recurrence vs. regression) of microbes on tumors, "spontaneous" and Coley's toxin-induced tumor regression, anticancer activities of ß-blockers and anti-inflammatory/anti-immune/antibiotic drugs, oncotaxis, surgery- and trauma-promoted metastasis, and impact of microbiota on tumors. Potential therapeutic strategies, such as Coley's toxin-like preparations, are proposed. This is the last article of our trilogy on carcinogenesis theories.

circSORBS1 inhibits lung cancer progression by sponging miR-6779-5p and directly binding RUFY3 mRNA.

Lung cancer is the primary cause of cancer-related death worldwide, and its global incidence and mortality rates remain high. The differential expression of circular RNAs (circRNAs) can affect the development of cancer, but the mechanisms by which circRNAs regulate lung cancer progression remain unclear. In this study, we identified circSORBS1, a circRNA that has not been previously described in lung cancer and is significantly underexpressed in lung cancer tissues, blood and cell lines, and the low expression of circSORBS1 correlated with tumour grade and prognosis. In vitro and in vivo functional experiments revealed that circSORBS1 overexpression inhibited cell proliferation and migration while enhancing apoptosis. Mechanistically, circSORBS1 acts as a sponge for miR-6779-5p, indirectly inhibiting RUFY3 mRNA degradation. Simultaneously, it binds to RUFY3 mRNA to enhance its stability. This dual regulatory mechanism leads to an increase in RUFY3 protein levels, which ultimately activates the YWHAE/BAD/BCL2 apoptotic signalling pathway and suppresses lung cancer progression. Our findings not only increase the knowledge about the regulatory pattern of circRNA expression but also provide new insights into the mechanisms by which circRNAs regulate lung cancer development.

Health Messaging Strategies for Vaping Prevention and Cessation Among Youth and Young Adults: A Systematic Review.

This systematic review evaluates health messaging strategies for the prevention and cessation of e-cigarette use among youth and young adults. Health messaging strategies were defined as the strategic process of developing messages with the intent to shape, reinforce, or change recipients' health attitudes and behaviors. McGuire's Communication/Persuasion Model guided the analysis of the messaging strategies, focusing on the model's five communication inputs (i.e. source, message, channel, audience, destination) and 14 persuasive outcomes. Nine databases were searched from January 2007 to September 2023. The inclusion criteria encompassed studies in English that presented quantitative data on messaging strategies aimed at discouraging vaping among youth and young adults. Each study was also coded for study characteristics and the utilization of theory. Out of 6,045 studies, 25 met the inclusion criteria. The reviewed studies exhibit a diverse array of research methods and a consistent integration of theories. The review emphasizes the nuanced main and interaction effects of various communication inputs, such as message features and audience characteristics, while also pointing out a research gap in message sources. In addition, the utilization of social media for effective messaging to engage the audience requires further research. Only one study specifically evaluated messaging strategies for vaping cessation. More research is imperative to develop targeted and tailored messages that effectively prevent and reduce vaping, especially among populations at higher risk of vaping-related harms, while also leveraging effective channels and innovative communication technologies to engage the audience.

The temporal variation of CH4 emissions embodied in Chinese supply chains, 2000-2020.

Although the issue of embodied pollutants in China's supply chains has garnered increasing attention, the dynamic changes occurring within them are unclear. Several existing studies analyze one-year or short-term data in supply chain. China's overall CH4 emissions have risen from 41.1 Tg in 2000 to 60 Tg in 2020, so conducting long-term analyses can yield a deeper understanding of the dynamic changes across the entire supply chain from production to consumption. This study uses the environmentally extended input-output analysis (EEIOA) and structural path analysis (SPA) methods to investigate the dynamic variation of China's embodied CH4 emissions in 20 industry sectors from 2000 to 2020, aiming to determine the key supply chain and key sectors. The results reveal that from the final demand perspective, consumption, investment and export drove 52.1%, 32%, and 15.9% of embodied CH4 emissions in 2020. The sector with the highest embodied CH4 emissions has changed from "Agriculture" in 2000 to "Construction" in 2010 to "Other service and activities" in 2020. The top listed supply chain path of embodied CH4 emissions has also evolved (starting from production to consumption) from "Agriculture → Rural consumption" in 2000 to "Agriculture → Food and tobacco → Urban consumption" in 2010 to "Agriculture → Urban consumption" in 2020. Notably, the high-ranked path, "Agriculture → Food and tobacco → Rural consumption", shows that the embodied CH4 emission flowing between agriculture and the food industry cannot be ignored. The supply chain path "Coal Mining → Nonmetal Mineral Products → Construction → Capital Formation" has risen from 17th in 2000 to 3rd in 2020. Thus, it is necessary to control CH4 emissions from sectors upstream, which are predominantly influenced by the construction industry, and a coordinated effort between sectors is also required to effectively reduce emissions. By 2020, the CH4 emissions driven by urban consumption were 3.1 times that of rural consumption. This study provides a comprehensive analysis of China's supply chain over the past two decades. In particular, it suggests policy interventions by controlling critical supply chain paths and key sectors associated with embodied CH4 emission, thereby facilitating the coordinated reduction of anthropogenic CH4 emissions.

Social media use, brand engagement, and tobacco product initiation among youth: Evidence from a prospective cohort study.

OBJECTIVE: To evaluate whether frequent social media use and liking/following tobacco brand accounts was associated with increased risk of tobacco and polytobacco initiation over approximately 1-year follow-up among youth with no prior tobacco use. METHODS: Associations between measures of social media engagement (daily social media use and liking/following tobacco brands) and tobacco initiation risk were examined using data from Waves 2 and 3 (2014-2015) of the US Population Assessment for Tobacco and Health study. Separate log-binomial models, accounting for missing data via multiple imputation and using propensity score adjustment to address confounding, estimated the adjusted relative risk (aRR) of any tobacco initiation and poly-use (2 + products) initiation at 1-year follow-up. RESULTS: Among the 8,672 youth with no prior tobacco use (49.3% female, mean [SD] age 14.1 [1.7]), 63.5% used social media at least daily, and 3.3% reported liking/following ≥ 1 tobacco brands on social media. Those reporting daily or more frequent social media use (compared to less) were at increased risk for tobacco (aRR 1.67; 95% CI 1.38-2.02) and polytobacco initiation (aRR 1.32; 95% CI 0.98-1.78). Although results were imprecise, liking/following ≥ 1 tobacco brands on social media (versus none) was associated with tobacco (aRR 1.34; 95% CI 0.95-1.89) or polytobacco initiation (aRR 1.60; 95% CI 0.99-2.60). In sensitivity analyses, liking/following cigarette or cigarillo brands was associated with polytobacco initiation. CONCLUSIONS: This study adds to a growing evidence-base describing the exposure of youth to tobacco-related social media content. Such content-often generated by tobacco companies-may contribute to youth tobacco initiation.

A Specific Mini-Intrabody Mediates Lysosome Degradation of Mutant Huntingtin.

Accumulation of misfolded proteins leads to many neurodegenerative diseases that can be treated by lowering or removing mutant proteins. Huntington's disease (HD) is characterized by the intracellular accumulation of mutant huntingtin (mHTT) that can be soluble and aggregated in the central nervous system and causes neuronal damage and death. Here, an intracellular antibody (intrabody) fragment is generated that can specifically bind mHTT and link to the lysosome for degradation. It is found that delivery of this peptide by either brain injection or intravenous administration can efficiently clear the soluble and aggregated mHTT by activating the lysosomal degradation pathway, resulting in amelioration of gliosis and dyskinesia in HD knock-in (KI-140Q) mice. These findings suggest that the small intrabody peptide linked to lysosomes can effectively lower mutant proteins and provide a new approach for treating neurodegenerative diseases that are caused by the accumulation of mutant proteins.

Generation of inactivated IL2RG and RAG1 monkeys with severe combined immunodeficiency using base editing.

Severe combined immunodeficiency (SCID) encompasses a range of inherited disorders that lead to a profound deterioration of the immune system. Among the pivotal genes associated with SCID, RAG1 and IL2RG play crucial roles. IL2RG is essential for the development, differentiation, and functioning of T, B, and NK cells, while RAG1 critically contributes to adaptive immunity by facilitating V(D)J recombination during the maturation of lymphocytes. Animal models carrying mutations in these genes exhibit notable deficiencies in their immune systems. Non-human primates (NHPs) are exceptionally well-suited models for biomedical research due to their genetic and physiological similarities to humans. Cytosine base editors (CBEs) serve as powerful tools for precisely and effectively modifying single-base mutations in the genome. Their successful implementation has been demonstrated in human cells, mice, and crop species. This study outlines the creation of an immunodeficient monkey model by deactivating both the IL2RG and RAG1 genes using the CBE4max system. The base-edited monkeys exhibited a severely compromised immune system characterized by lymphopenia, atrophy of lymphoid organs, and a deficiency of mature T cells. Furthermore, these base-edited monkeys were capable of hosting and supporting the growth of human breast cancer cells, leading to tumor formation. In summary, we have successfully developed an immunodeficient monkey model with the ability to foster tumor growth using the CBE4max system. These immunodeficiency monkeys show tremendous potential as valuable tools for advancing biomedical and translational research.

Compliance With the US Food and Drug Administration's Guidelines for Health Warning Labels and Engagement in Little Cigar and Cigarillo Content: Computer Vision Analysis of Instagram Posts.

Background: Health warnings in tobacco advertisements provide health information while also increasing the perceived risks of tobacco use. However, existing federal laws requiring warnings on advertisements for tobacco products do not specify whether the rules apply to social media promotions. Objective: This study aims to examine the current state of influencer promotions of little cigars and cigarillos (LCCs) on Instagram and the use of health warnings in influencer promotions. Methods: Instagram influencers were identified as those who were tagged by any of the 3 leading LCC brand Instagram pages between 2018 and 2021. Posts from identified influencers, which mentioned one of the three brands were considered LCC influencer promotions. A novel Warning Label Multi-Layer Image Identification computer vision algorithm was developed to measure the presence and properties of health warnings in a sample of 889 influencer posts. Negative binomial regressions were performed to examine the associations of health warning properties with post engagement (number of likes and comments). Results: The Warning Label Multi-Layer Image Identification algorithm was 99.3% accurate in detecting the presence of health warnings. Only 8.2% (n=73) of LCC influencer posts included a health warning. Influencer posts that contained health warnings received fewer likes (incidence rate ratio 0.59, P<.001, 95% CI 0.48-0.71) and fewer comments (incidence rate ratio 0.46, P<.001, 95% CI 0.31-0.67). Conclusions: Health warnings are rarely used by influencers tagged by LCC brands' Instagram accounts. Very few influencer posts met the US Food and Drug Administration's health warning requirement of size and placement for tobacco advertising. The presence of a health warning was associated with lower social media engagement. Our study provides support for the implementation of comparable health warning requirements to social media tobacco promotions. Using an innovative computer vision approach to detect health warning labels in influencer promotions on social media is a novel strategy for monitoring health warning compliance in social media tobacco promotions.

Structural insights into the assembly of gp130 family cytokine signaling complexes.

The interleukin-6 (IL-6) family cytokines signal through gp130 receptor homodimerization or heterodimerization with a second signaling receptor and play crucial roles in various cellular processes. We determined cryo-electron microscopy structures of five signaling complexes of this family, containing full receptor ectodomains bound to their respective ligands ciliary neurotrophic factor, cardiotrophin-like cytokine factor 1 (CLCF1), leukemia inhibitory factor, IL-27, and IL-6. Our structures collectively reveal similarities and differences in the assembly of these complexes. The acute bends at both signaling receptors in all complexes bring the membrane-proximal domains to a ~30 angstrom range but with distinct distances and orientations. We also reveal how CLCF1 engages its secretion chaperone cytokine receptor-like factor 1. Our data provide valuable insights for therapeutically targeting gp130-mediated signaling.

Moralization of E-cigarette Use and Regulation: A Mixed-Method Computational Analysis of Opinion Polarization.

E-cigarette use, or vaping, is undergoing a process of moralization in which issues about vaping evolve from being morally neutral to having discernible moral implications. Using Moral Foundations Theory, this study compared the moral narratives underlying polarized views about e-cigarette use and regulation. We integrated computational and human strategies by conducting the Chow test on the time series data and classification, topic modeling, and Chi-square tests on posts (N = 2,669) from 26 pro-vaping and 19 anti-vaping Facebook Pages. The observation period (August 1, 2019 to March 5, 2020) encompassed the outbreak of "e-cigarette or vaping product use associated lung injury" (EVALI), deaths and subsequent legislation. Results revealed that pro-vaping posts were more likely than anti-vaping posts to mention Fairness/cheating and Authority/subversion, involving a conspiracy belief in an "e-cigarettes vs. Big Tobacco" rivalry, while anti-vaping posts were more likely to mention Sanctity/degradation. There were no significant differences between pro-vaping and anti-vaping posts in the likelihood of mentioning Care/harm or Loyalty/betrayal. Nevertheless, according to the topic modeling results, the use of moral foundations varied between pro-vaping and anti-vaping narratives, with the meanings of Care/harm and Loyalty/betrayal dependent on the post author's group affiliation. Health interventions can tailor persuasive messages to different moral values and debunk misinformation about public health policies to mitigate the vaping epidemic. Theoretical implications are also discussed.

CREAMMIST: an integrative probabilistic database for cancer drug response prediction.

Extensive in vitro cancer drug screening datasets have enabled scientists to identify biomarkers and develop machine learning models for predicting drug sensitivity. While most advancements have focused on omics profiles, cancer drug sensitivity scores precalculated by the original sources are often used as-is, without consideration for variabilities between studies. It is well-known that significant inconsistencies exist between the drug sensitivity scores across datasets due to differences in experimental setups and preprocessing methods used to obtain the sensitivity scores. As a result, many studies opt to focus only on a single dataset, leading to underutilization of available data and a limited interpretation of cancer pharmacogenomics analysis. To overcome these caveats, we have developed CREAMMIST (https://creammist.mtms.dev), an integrative database that enables users to obtain an integrative dose-response curve, to capture uncertainty (or high certainty when multiple datasets well align) across five widely used cancer cell-line drug-response datasets. We utilized the Bayesian framework to systematically integrate all available dose-response values across datasets (>14 millions dose-response data points). CREAMMIST provides easy-to-use statistics derived from the integrative dose-response curves for various downstream analyses such as identifying biomarkers, selecting drug concentrations for experiments, and training robust machine learning models.

The Impact of Influencers on Cigar Promotions: A Content Analysis of Large Cigar and Swisher Sweets Videos on TikTok.

Little is known about the content, promotions, and individuals in cigar-related videos on TikTok. TikTok videos with large cigar and Swisher Sweets-related hashtags between July 2016 and September 2020 were analyzed. Follower count was used to identify influencers. We compared content characteristics and demographics of featured individuals between cigar types, and by influencer status. We also examined the association between content characteristics and video engagement. Compared to large cigar videos, Swisher Sweets videos were more likely to feature arts and crafts with cigar packages, cannabis use, and flavored products. In addition, Swisher Sweets videos were also more likely to feature females, Black individuals, and younger individuals. Both Swisher Sweets and large cigar influencers posted more videos of cigar purchasing behaviors than non-influencers, which was associated with more video views. None of the videos disclosed sponsorship with #ad or #sponsored. Videos containing the use of cigar packages for arts and crafts, and flavored products highlight the importance of colorful packaging and flavors in the appeal of Swisher Sweets cigars, lending support for plain packaging requirements and the prohibition of flavors in cigar products to decrease the appeal of cigars. The presence and broad reach of cigar promotions on TikTok requires stricter enforcement of anti-tobacco promotion policies.

TFEB, a master regulator of autophagy and biogenesis, unexpectedly promotes apoptosis in response to the cyclopentenone prostaglandin 15d-PGJ2.

Transcriptional factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis, is generally regarded as a pro-survival factor. Here, we identify that besides its effect on autophagy induction, TFEB exerts a pro-apoptotic effect in response to the cyclopentenone prostaglandin 15-deoxy-∆-12,14-prostaglandin J2 (15d-PGJ2). Specifically, 15d-PGJ2 promotes TFEB translocation from the cytoplasm into the nucleus to induce autophagy and lysosome biogenesis via reactive oxygen species (ROS) production rather than mTORC1 inactivation. Surprisingly, TFEB promotes rather than inhibits apoptosis in response to 15d-PGJ2. Mechanistically, ROS-mediated TFEB translocation into the nucleus transcriptionally upregulates the expression of ATF4, which is required for apoptosis elicited by 15d-PGJ2. Additionally, inhibition of TFEB activation by ROS scavenger N-acetyl cysteine or inhibition of protein synthesis by cycloheximide effectively compromises ATF4 upregulation and apoptosis in response to 15d-PGJ2. Collectively, these results indicate that ROS-induced TFEB activation exerts a novel role in promoting apoptosis besides its role in regulating autophagy in response to 15d-PGJ2. This work not only evidences how TFEB is activated by 15d-PGJ2, but also unveils a previously unexplored role of ROS-dependent activation of TFEB in modulating cell apoptosis in response to 15d-PGJ2.

Intravenous AAV9 administration results in safe and widespread distribution of transgene in the brain of mini-pig.

Animal models are important for understanding the pathogenesis of human diseases and for developing and testing new drugs. Pigs have been widely used in the research on the cardiovascular, skin barrier, gastrointestinal, and central nervous systems as well as organ transplantation. Recently, pigs also become an attractive large animal model for the study of neurodegenerative diseases because their brains are very similar to human brains in terms of mass, gully pattern, vascularization, and the proportions of the gray and white matters. Although adeno-associated virus type 9 (AAV9) has been widely used to deliver transgenes in the brain, its utilization in large animal models remains to be fully characterized. Here, we report that intravenous injection of AAV9-GFP can lead to widespread expression of transgene in various organs in the pig. Importantly, GFP was highly expressed in various brain regions, especially the striatum, cortex, cerebellum, hippocampus, without detectable inflammatory responses. These results suggest that intravenous AAV9 administration can be used to establish large animal models of neurodegenerative diseases caused by gene mutations and to treat these animal models as well.

JUUL the heartbreaker: Twitter analysis of cardiovascular health perceptions of vaping.

INTRODUCTION: The public most frequently associates tobacco use solely with pulmonary health risks, despite heart disease being the leading cause of death in smokers. The health perceptions of e-cigarettes, especially cardiovascular health, have not been well studied. We aimed to evaluate the prevalence and health perceptions of tweets related to cardiovascular, pulmonary, and brain health - three organ systems for which tobacco use is a major disease risk factor. METHODS: We examined the cardiovascular, pulmonary, and brain health perceptions of vaping and JUUL on Twitter, followed by a content analysis of tweets pertaining to the cardiovascular risks. A Twitter firehose API scraped about 6.2 million publicly available tweets from 2015-2019 that contained vaping-related terms, and a separate dataset of about 1.9 million tweets that contained the term JUUL. A quantitative content analysis (n=2145) of tweets was subsequently conducted to assess the health perceptions of vaping and JUUL. Two trained coders independently assessed the posts and Twitter profiles to determine age (<18 or ≥18 years), sex, race, sentiment towards JUUL, and vaping-related topics. RESULTS: The majority of tweets containing vaping or JUUL-related terms did not also contain cardiovascular, pulmonary, or brain health terms (97.99% and 96.67%, respectively). Multiple linear regression analysis showed that youth (<18 years), females, non-White individuals, mention of a flavor, and mention of cardiovascular health harm words were associated with more positive sentiments towards JUUL. Pearson's chi-squared analyses indicated that youth were more likely to mention a JUUL flavor. Females and youth were more likely to reference cardiovascular terms with humor. CONCLUSIONS: The cardiovascular health risks of vaping are not fully recognized by the public. Vulnerable populations such as youth and females reference JUUL with cardiovascular-related words that downplay the severity of tobacco as a major risk factor for cardiovascular disease.

Mechanical stretch activates glycometabolism-related enzymes via estrogen in C2 C12 myoblasts.

Moderate exercise improves glycometabolic disorder and type 2 diabetes mellitus in menopausal females. So far, the effect of exercise-induced estrogen on muscular glycometabolism is not well defined. The current study was designed to explore the effect of mechanical stretch-induced estrogen on glycometabolism in mouse C2 C12 myoblasts. The mouse C2 C12 myoblasts in vitro were assigned randomly to the control (C), stretch (S), and stretch plus aromatase inhibitor anastrozole (SA) groups. Cells in the S group were stretched by the Flexcell FX-5000™ system (15% magnitude, 1 Hz frequency, and 6-hr duration) whereas those in the SA group were treated with 400 µg/ml anastrozole before the same stretching. Glucose uptake, estradiol levels, PFK-1 levels, and oxygen consumption rate were determined, and the expression of HK, PI3K, p-AKT, AKT, and GLUT4 proteins were semiquantified with western blot analysis. Compared to the control, the estradiol level, oxygen consumption rate, expression of HK, PI3K, and PFK-1 proteins, the ratio of p-AKT to AKT, and the ratio of GLUT4 in the cell membrane to that in the whole cell were higher in the S group. On the other hand, the estradiol level, glucose uptake, expression of PFK-1 and GLUT4 proteins, oxygen consumption rate, expression of HK protein, and the ratio of p-AKT/AKT were lower in the myoblasts in the SA group than those in the S group. The level of estradiol was positively correlated with glucose uptake (p < .01, r = .818). Therefore, mechanical stretch-induced estrogen increased the expression of glycometabolism-related enzymes and proteins in the mouse C2 C12 myoblasts.

Constructing 2D BiOIO3/MoS2 Z-scheme heterojunction wrapped by C500 as charge carriers transfer channel: Enhanced photocatalytic activity on gas-phase heavy metal oxidation.

A new ternary composite BiOIO3/MoS2/C500 was prepared via sol-gel and hydrothermal method. The energy bands, surface structures and optical properties of the as-prepared samples were characterized by XRD, SEM, TEM, UV-vis DRS, BET, XPS, PL, ESR and electrochemical measurement. The density functional theory (DFT) was adopted to explore the capability as well. It is discovered that BiOIO3/MoS2/C500 possesses excellent Z-scheme heterostructure for separating photogenerated electron-hole pairs mainly provided by BiOIO3/MoS2, and large specific surface area as charge carriers transfer channel mainly provided by C500, which can accelerate charges to transfer to the surface reaction area for photocatalytic oxidation. Then, the ternary catalyst was utilized to remove gas-phase Hg0 including its oxidation product, and possessed the highest removal efficiency of 78.32%, which is much higher than that of its pure component. Meanwhile, the photocatalytic activity of ternary catalyst are of high stability, and the product after the reaction is HgO and can be adsorbed on BiOIO3/MoS2/C500, which is detected by high resolution XPS. The loading manner provides a new vision for both photocatalysis and adsorption.

Mechanical stretch enhances sex steroidogenesis in C2C12 skeletal muscle cells.

Skeletal muscle contains estrogens and estrogen synthesis-related enzymes. However, it has not been reported whether myoblasts cultured in vitro also express these enzymes. The purpose of the current study was to address these issues and to explore the effects of mechanical stretch on the enzyme system. The in vitro cultured C2C12 mouse myoblasts were divided into the control, stretch, testosterone and stretch plus testosterone groups. Cells in the stretch and stretch plus testosterone groups were mechanically stretched with the Flexercell cell stress loading device at an amplitude of 10% and in a frequency of 0.5 Hz for 8 h. Cells in the testosterone and stretch plus testosterone groups were incubated with 100 nM testosterone for 24 h before distraction. Following the treatments, cell proliferation and estradiol levels, as well as the expressions of 17ß-hydroxysteroid (17ß-HSD), 3ß-hydroxysteroid (3ß-HSD) and aromatase were analyzed. Compared to the control, the cell proliferation in all experimental groups increased significantly, the estradiol levels in the mechanically stretched groups were significantly higher, and, moreover, the estradiol levels were positively correlated with the cell proliferation (r = 0.615, p < 0.01). Additionally, analyses of aromatase protein and mRNA showed that, compared to the control, their levels were significantly increased upon stretching and testosterone exposure. Similarly, the protein and mRNA levels of both 3ß-HSD and 17ß-HSD in the stretched cells differed significantly from the control. In the presence of aromatase and 5α-reductase inhibitors, the protein and mRNA levels of these enzymes altered significantly compared to the control. Conclusions: Steroid synthases were detected in the C2C12 myoblasts cultured in vitro, the synthesized estrogen was closely related to the cell proliferation, and mechanical stretch was the external factor that affected the expression of the estrogen synthesis-related enzymes.

Sensitive and Precise Characterization of Combinatorial Histone Modifications by Selective Derivatization Coupled with RPLC-EThcD-MS/MS.

Deciphering the combinatorial histone codes has been a long-standing interest in the epigenetics field, which requires the reliable and robust characterization of the post-translational modifications (PTMs) coexisting on histones. To this end, weak cation exchange hydrophilic interaction liquid chromatography is commonly used in middle-down liquid chromatography-mass spectrometry approaches for online separation of variously modified histone peptides. Here we provide a novel strategy that combines the selective histone peptide derivatization using N-hydroxysuccinimide propionate ester with reversed-phase liquid chromatography (RPLC) for the robust, sensitive, and reliable characterization of combinatorial histone PTMs. Derivatization amplifies the subtle physical differences between similarly modified histone peptides, thereby allowing baseline separation of these peptides by standard RPLC. Also, the sensitivity of MS is enhanced greatly by derivatization due to the increased peptide hydrophobicity and concentrated charge-state envelope during electrospray ionization. Furthermore, we systematically optimized the dual electron transfer and higher energy collision dissociation and achieved near-complete peptide sequence coverage in MS/MS spectra, allowing highly precise and reliable PTM identification. Using this method, we identified 311 and 293 combinations of histone H3 PTMs from the lymphoma cells Karpas-422 with/without drug treatment, confirming the advantages of our method in serving as a platform for profiling combinatorial histone PTMs.

Low-fidelity alternative DNA repair carcinogenesis theory may interpret many cancer features and anticancer strategies.

We have proposed that the low-fidelity compensatory backup alternative DNA repair pathways drive multistep carcinogenesis. Here, we apply it to interpret the clinical features of cancer, such as mutator phenotype, tissue specificity, age specificity, diverse types of cancers originated from the same type of tissue, cancer susceptibility of patients with DNA repair-defective syndromes, development of cancer only for a selected number of individuals among those that share the same genetic defect, invasion and metastasis. Clinically, the theory predicts that to improve the efficacy of molecular targeted or synthetic lethal therapy, it may be crucial to inhibit the low-fidelity compensatory alternative DNA repair either directly or by blocking the signal transducers of the sustained microenvironmental stress.