Exploration of novel clusters and prognostic value of immune­related signatures and identify HAMP as hub gene in colorectal cancer.

Immune checkpoint inhibitors currently serve an important role in prolonging patients' overall survival. However, the prognostic signatures of immune checkpoint inhibitors in colorectal cancer (CRC) remain uncertain and more knowledge on the genetic characteristics of colorectal cancer is needed. Patients with CRC from The Cancer Genome Atlas were classified into high-immunity group and low-immunity group based on median scores from single-sample gene set enrichment analysis using the GSVA package. We explored immune status by immune scores, stromal scores and tumor purity scores in ESTIMATE package and surveyed the difference of immune cells distribution with CIBERSORT package. Eighteen genes were selected using the LASSO Cox regression method and a prognostic risk model was constructed. Compared with patients in the low-risk group, those in the high-risk group had a significantly shorter survival time. For assessment of the prognostic validity of the risk model, receiver operating characteristic curves with areas under the curve of 0.769, 0.774 and 0.771 for 1, 3 and 5 years respectively. Differences in molecular mechanisms between high- and low-risk groups were analyzed using the clusterProfiler package. Tumor Immune Dysfunction and Exclusion data were downloaded and analyzed. The top 5 enriched pathways in the high-risk group involved 'calcium signaling', 'dilated cardiomyopathy', 'extracellular matrix receptor interaction', 'hypertrophic cardiomyopathy' and 'neuroactive ligand receptor interaction'. HAMP was identified as a hub gene, which was highly expressed in tumor samples. The results of the present study indicate that the prognostic model based on both immune-related genes and HAMP has the potential to support personalized treatment.

Relationship among positive self-esteem, physical literacy, and physical activity in college students: a study of a mediation model.

Background: In light of the substantial decline in physical activity during college years, this study aims to examine the relationship between positive self-esteem, physical literacy, and physical activity in order to investigate the mechanisms for improving physical activity in college students and to provide a foundation for future interventions. Methods: A cross-sectional study design was employed in this study. A total of 5,184 Participants, aged between 17 and 21 years (M = 18.97, SD = 1.10), completed the Positive Version of Rosenberg Self-esteem Scales, Perceived Physical Literacy Instruments, and the International Physical Activity Questionnaires. A mediation model was utilized to explore the associations among the three concepts. Results: The three regression models were as follows: Physical literacy = 18.03 + 0.98 *Self-esteem, Physical activity = 43.23 + 0.16 *Self-esteem, and Physical activity = 28.18 + 0.11 *Physical literacy. Positive self-esteem, physical literacy, and physical activity were significantly linked with each other. Physical literacy mediated 26.93% of the effect, indicating a partial mediator in the relationship between positive self-esteem and physical activity. Conclusion: The mediating effect of physical literacy on the relationship between positive self-esteem and physical activity was identified. Our findings support the development of positive self-esteem and physical literacy in college physical education curricula as part of an overall program to address students' physical inactivity at school and in the future. This study provides a new intervention perspective for improving physical inactivity in college students.

Development of an interpretable machine learning-based intelligent system of exercise prescription for cardio-oncology preventive care: A study protocol.

Background: Cardiovascular disease (CVD) and cancer are the first and second causes of death in over 130 countries across the world. They are also among the top three causes in almost 180 countries worldwide. Cardiovascular complications are often noticed in cancer patients, with nearly 20% exhibiting cardiovascular comorbidities. Physical exercise may be helpful for cancer survivors and people living with cancer (PLWC), as it prevents relapses, CVD, and cardiotoxicity. Therefore, it is beneficial to recommend exercise as part of cardio-oncology preventive care. Objective: With the progress of deep learning algorithms and the improvement of big data processing techniques, artificial intelligence (AI) has gradually become popular in the fields of medicine and healthcare. In the context of the shortage of medical resources in China, it is of great significance to adopt AI and machine learning methods for prescription recommendations. This study aims to develop an interpretable machine learning-based intelligent system of exercise prescription for cardio-oncology preventive care, and this paper presents the study protocol. Methods: This will be a retrospective machine learning modeling cohort study with interventional methods (i.e., exercise prescription). We will recruit PLWC participants at baseline (from 1 January 2025 to 31 December 2026) and follow up over several years (from 1 January 2027 to 31 December 2028). Specifically, participants will be eligible if they are (1) PLWC in Stage I or cancer survivors from Stage I; (2) aged between 18 and 55 years; (3) interested in physical exercise for rehabilitation; (4) willing to wear smart sensors/watches; (5) assessed by doctors as suitable for exercise interventions. At baseline, clinical exercise physiologist certificated by the joint training program (from 1 January 2023 to 31 December 2024) of American College of Sports Medicine and Chinese Association of Sports Medicine will recommend exercise prescription to each participant. During the follow-up, effective exercise prescription will be determined by assessing the CVD status of the participants. Expected outcomes: This study aims to develop not only an interpretable machine learning model to recommend exercise prescription but also an intelligent system of exercise prescription for precision cardio-oncology preventive care. Ethics: This study is approved by Human Experimental Ethics Inspection of Guangzhou Sport University. Clinical trial registration: http://www.chictr.org.cn, identifier ChiCTR2300077887.

Expressions of m6A RNA methylation regulators and their clinical predictive value in cervical squamous cell carcinoma and endometrial adenocarcinoma.

The mortality caused by cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) ranks second among female malignant tumour deaths, but their diagnostic and therapeutic targets are still limited. N6-methyladenosine (m6A) is the most common and extensive modification in mRNA molecules, and its methylation regulators participate in regulating the occurrence and development of many tumours. However, whether m6A RNA methylation regulators can be used as independent prognostic indicators of CESC remains unknown. This study unveiled differential expression of 20 m6A RNA methylation regulators between normal and CESC tumour samples, which RNA sequence data and clinical information were obtained from TCGA database. As a result, five m6A RNA methylation regulators (FTO, HNRNPA2B1, RBM15, IGF2BP1, IGF2BP3) were identified to be significantly linked to CESC tumour status. After Lasso cox regression analysis, six m6A RNA methylation regulators (YTHDC2, YTHDC1, ALKBH5, ZC3H13, RBMX, YTHDF1) were chosen to construct a risk signature. CESC patients were then classified as high-risk and low-risk group based on the median risk score. The overall survival (OS) of the CESC patients in high-risk group was significantly lower than that in low-risk group, and the area under curve (AUC) is 0.718. Moreover, the risk model can be an independent prognosis factors for CESC patients and can predict OS of CESC patients with different clinical factors. In conclusion, m6A RNA methylation regulators are closely correlated with CESC clinical characteristics and the selected six m6A RNA methylation regulators may be useful for CESC patients personalized treatment.

Loss of Fbxw7 in Sertoli cells impairs testis development and causes infertility in mice†.

F-box and WD-40 domain protein 7 (Fbxw7) is a component of the Skp1-Cdc53/Cullin-F-box-protein complex (SCF/ß-TrCP), which is an E3 ubiquitin ligase that mediates protein degradation. This complex has recently been shown to negatively regulate spermatogonial stem cell self-renewal; however, its roles in Sertoli cell (SC) proliferation, differentiation, and function remain to be established. In this study, we generated conditional mutant mice with SC-specific deletion of Fbxw7 via the Cre-loxP system. Fbxw7 deficiency in SCs impaired testis development, which is characterized by age-dependent tubular atrophy, excessive germ cell loss, and spermatogenic arrest, and the mutant males were infertile at 7 months old. Fbxw7 ablation also compromised cytoskeletal organization and cell polarity of SCs, as well as integrity of the blood-testis barrier. In addition, the transcript levels of cell markers for germ cells, Leydig cells, and SCs were significantly decreased in Fbxw7 mutant mice. Importantly, protein levels of GATA-4, a transcription factor that plays a crucial role in SC maturation and testis development, were progressively decreased in control SCs after postnatal day 14, whereas levels were aberrantly elevated in Fbxw7-deleted SCs. Interestingly, the Gata-4 messenger RNA levels remained stable following Fbxw7 deletion. Fbxw7 silencing in SCs also induced progressive Leydig cell inefficiency and testosterone insufficiency. Collectively, these results demonstrate that Fbxw7 expression is required for SC maturation and function, potentially through degradation of GATA-4, to support pubertal testis development and spermatogenesis.

[AMPK regulates mitochondrial oxidative stress in C2C12 myotubes induced by electrical stimulations of different intensities].

OBJECTIVE: To study effect of electrical stimulations of different intensities on mitochondrial oxidative stress in C2C12 myotubes and explore the molecular mechanisms. METHODS: After 7 days of differentiation, C2C12 myotubes were subjected to electrical stimulations (15 V, 3Hz, 30 ms) for 60, 120, or 180 min, and the morphological changes of muscular tubes were observed under inverted microscope. The levels of MDA and SOD activity of the cells were detected, and flow cytometry was used to detect mitochondrial reactive oxygen species (ROS) and membrane potential. Western blotting was used to detect the expression of PGC1, AMPK-Ser485, AMPK-Thr172, and AMPK in the cells. RESULTS: No significant changes occurred in the morphology of C2C12 myotubes in response to electrical stimulations. Electrical stimulation for 60 min resulted in significantly increased levels of MDA, AMPK-Ser485 and AMPK-Thr172 in the cells (P<0.05); simulations of the cells for 120 and 180 min caused significantly increased MDA, ROS, mitochondrial ROS, AMPK-Ser485 and PGC1 along with marked reduction of mitochondrial membrane potential (P<0.05). CONCLUSION: Electrical stimulation significantly activates oxidative stress, and a longer stimulation time causes stronger mitochondrial oxidation. AMPK-Thr172 regulates oxidative stress induced by stimulations for a moderate time length, while AMPK-Ser485 and PGC1 function to modulate oxidative stress following prolonged stimulations.

[Rictor/mTORC2 regulates blood-testis barrier and spermatogenesis in mice].

OBJECTIVE: To investigate the role of Rictor/mTORC2 in the formation of blood testis barrier (BTB), testicular development, and spermatogenesis. METHODS: Amh Cre positive mice homozygous for rictor loxP with Sertoli cell specific deletion of rictor were obtained by cross breeding Amh Cre mice with rictor loxP mice. The histology of the reproductive organs, seminiferous tubules and epididymis of the transgenic mice was observed with HE staining. The cell subgroups of the germ cells in the seminiferous tubule were detected by flow cytometry with propidium iodide labeling. The expression levels of Ki 67 and separase were detected with immunofluorescence assay, and the expression levels of BTB associated proteins were detected with immunofluorescence and Western blotting. RESULTS: Compared with the control (Amh Cre-, rictorloxP/loxP or rictorloxP/-) mice, the mice with Sertoli cell specific rictor deletion showed significantly decreased testicular weight and epididymis weight (P<0.05), significantly increased diploid cells (P<0.01), and decreased haploid cells (P<0.01) but comparable tetraploid cells and similar expression levels of Ki 67 and separase. The mice with rictor knockout also showed aberrant localization of BTB associated proteins, which were scattered over the whole seminiferous epithelium, but the expression levels of the protein remained stable. CONCLUSION: Rictor in testicular Sertoli cells is essential for maintaining BTB integrity and function and ensuring normal spermatogenesis in mice.

Rictor Regulates Spermatogenesis by Controlling Sertoli Cell Cytoskeletal Organization and Cell Polarity in the Mouse Testis.

Maintenance of cell polarity is essential for Sertoli cell and blood-testis barrier (BTB) function and spermatogenesis; however, the signaling mechanisms that regulate the integrity of the cytoskeleton and polarity of Sertoli cells are not fully understood. Here, we demonstrate that rapamycin-insensitive component of target of rapamycin (TOR) (Rictor), a core component of mechanistic TOR complex 2 (mTORC2), was expressed in the seminiferous epithelium during testicular development, and was down-regulated in a cadmium chloride-induced BTB damage model. We then conditionally deleted the Rictor gene in Sertoli cells and mutant mice exhibited azoospermia and were sterile as early as 3 months old. Further study revealed that Rictor may regulate actin organization via both mTORC2-dependent and mTORC2-independent mechanisms, in which the small GTPase, ras-related C3 botulinum toxin substrate 1, and phosphorylation of the actin filament regulatory protein, Paxillin, are involved, respectively. Loss of Rictor in Sertoli cells perturbed actin dynamics and caused microtubule disarrangement, both of which accumulatively disrupted Sertoli cell polarity and BTB integrity, accompanied by testicular developmental defects, spermiogenic arrest and excessive germ cell loss in mutant mice. Together, these findings establish the importance of Rictor/mTORC2 signaling in Sertoli cell function and spermatogenesis through the maintenance of Sertoli cell cytoskeletal dynamics, BTB integrity, and cell polarity.

Rictor/mTORC2 pathway in oocytes regulates folliculogenesis, and its inactivation causes premature ovarian failure.

Molecular basis of ovarian folliculogenesis and etiopathogenesis of premature ovarian failure (POF), a common cause of infertility in women, are not fully understood. Mechanistic target of rapamycin complex 2 (mTORC2) is emerging as a central regulator of cell metabolism, proliferation, and survival. However, its role in folliculogenesis and POF has not been reported. Here, we showed that the signaling activity of mTORC2 is inhibited in a 4-vinylcyclohexene diepoxide (VCD)-induced POF mouse model. Notably, mice with oocyte-specific ablation of Rictor, a key component of mTORC2, demonstrated POF phenotypes, including massive follicular death, excessive loss of functional ovarian follicles, abnormal gonadal hormone secretion, and consequently, secondary subfertility in conditional knock-out (cKO) mice. Furthermore, reduced levels of Ser-473-phosphorylated Akt and Ser-253-phosphorylated Foxo3a and elevated pro-apoptotic proteins, Bad, Bax, and cleaved poly ADP-ribose polymerase (PARP), were observed in cKO mice, replicating the signaling alterations in 4-VCD-treated ovaries. These results indicate a critical role of the Rictor/mTORC2/Akt/Foxo3a pro-survival signaling axis in folliculogenesis. Interestingly, loss of maternal Rictor did not cause obvious developmental defects in embryos or placentas from cKO mice, suggesting that maternal Rictor is dispensable for preimplantation embryonic development. Our results collectively indicate key roles of Rictor/mTORC2 in folliculogenesis, follicle survival, and female fertility and support the utility of oocyte-specific Rictor knock-out mice as a novel model for POF.

Inhibition of endometrial cancer by n-3 polyunsaturated fatty acids in preclinical models.

Although preclinical and epidemiologic studies have shown the importance of n-3 polyunsaturated fatty acids (PUFA) in the prevention of hormone-responsive cancers such as breast cancer, evidence of the association between n-3 PUFAs and endometrial cancer risk is limited and no previous study has examined the effect of n-3 PUFAs on endometrial cancer in cellular and animal models. In this study, we demonstrated that docosahexenoic acid (DHA) dose- and time-dependently inhibited endometrial cancer cell proliferation, colony formation, and migration and promoted apoptosis. Dietary n-3 PUFAs efficiently prevented endometrial cancer cell growth in xenograft models. Moreover, ectopic expression of fat-1, a desaturase, catalyzed the conversion of n-6 to n-3 PUFAs and produced n-3 PUFAs endogenously, also suppressed endometrial tumor cell growth and migration, and potentiated apoptosis in endometrial cancer cell lines. Interestingly, implanted endometrial cancer cells were unable to grow in fat-1 transgenic SCID mice. Further study revealed that mTOR signaling, which plays an essential role in cell proliferation and endometrial tumorigenesis, is a target of n-3 PUFAs. Exogenous or endogenous n-3 PUFAs efficiently suppressed both mTOR complex 1 (mTORC1) and mTORC2 in vitro and in vivo. Moreover, both dietary n-3 PUFAs and transgenic expression of fat-1 in mice effectively repressed mTORC1/2 signaling and endometrial growth elicited by unopposed estrogen. Taken together, our findings provide comprehensive preclinical evidences that n-3 PUFAs efficiently prevent endometrial cancer and establish mTORC1/2 as a target of n-3 PUFAs.

Activation of mTORC1 in collecting ducts causes hyperkalemia.

Mutation of TSC (encoding tuberous sclerosis complex protein) and activation of mammalian target of rapamycin (mTOR) have been implicated in the pathogenesis of several renal diseases, such as diabetic nephropathy and polycystic kidney disease. However, the role of mTOR in renal potassium excretion and hyperkalemia is not known. We showed that mice with collecting-duct (CD)-specific ablation of TSC1 (CDTsc1KO) had greater mTOR complex 1 (mTORC1) activation in the CD and demonstrated features of pseudohypoaldosteronism, including hyperkalemia, hyperaldosteronism, and metabolic acidosis. mTORC1 activation caused endoplasmic reticulum stress, columnar cell lesions, and dedifferentiation of CD cells with loss of aquaporin-2 and epithelial-mesenchymal transition-like phenotypes. Of note, mTORC1 activation also reduced the expression of serum- and glucocorticoid-inducible kinase 1, a crucial regulator of potassium homeostasis in the kidney, and decreased the expression and/or activity of epithelial sodium channel-α, renal outer medullary potassium channel, and Na(+), K(+)-ATPase in the CD, which probably contributed to the aldosterone resistance and hyperkalemia in these mice. Rapamycin restored these phenotypic changes. Overall, this study identifies a novel function of mTORC1 in regulating potassium homeostasis and demonstrates that loss of TSC1 and activation of mTORC1 results in dedifferentiation and dysfunction of the CD and causes hyperkalemia. The CDTsc1KO mice provide a novel model for hyperkalemia induced exclusively by dysfunction of the CD.