Mesenchymal stem cells (MSCs) possess the capacity for self-renewal and multipotency. The traditional approach to manipulating MSC's fate choice predominantly relies on biochemical stimulation. Accumulating evidence also suggests the role of physical input in MSCs differentiation. Therefore, investigating mechanotransduction at the molecular level and related to tissue-specific cell functions sheds light on the responses secondary to mechanical forces. In this review, a new frontier aiming to optimize the cultural parameters was illustrated, i.e. spatial boundary condition, which recapitulates in vivo physiology and facilitates the investigations of cellular behavior. The concept of mechanical memory was additionally addressed to appreciate how MSCs store imprints from previous culture niches. Besides, different types of forces as physical stimuli were of interest based on the association with the respective signaling pathways and the differentiation outcome. The downstream mechanoreceptors and their corresponding effects were further pinpointed. The cardiovascular system or immune system may share similar mechanisms of mechanosensing and mechanotransduction; for example, resident stem cells in a vascular wall and recruited MSCs in the bloodstream experience mechanical forces such as stretch and fluid shear stress. In addition, baroreceptors or mechanosensors of endothelial cells detect changes in blood flow, pass over signals induced by mechanical stimuli and eventually maintain arterial pressure at the physiological level. These mechanosensitive receptors transduce pressure variation and regulate endothelial barrier functions. The exact signal transduction is considered context dependent but still elusive. In this review, we summarized the current evidence of how mechanical stimuli impact MSCs commitment and the underlying mechanisms. Future perspectives are anticipated to focus on the application of cardiovascular bioengineering and regenerative medicine.

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Acute kidney injury (AKI) is one of the most challenging clinical problems in kidney disease due to serious complications and high mortality rate, which can lead to acute lung injury (ALI) through inflammatory reactions and oxidative stress. Adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway has been reported to be involved in the development of renal ischemia-reperfusion through autophagy and it remains unclear whether AMPK/mTOR pathway has an effect on the AKI-induced ALI. In this study, we aimed to investigate the effects of autophagy-related AMPK/mTOR signaling pathway on inflammatory factors and oxidative stress in an AKI-induced ALI model. The 48 male Sprague–Dawley rats were divided into four groups randomly: (i) sham, (ii) ischemia/reperfusion injury (IRI), (iii) IRI + rapamycin (RA), and (iv) IRI + 3-methyladenine (3-MA). Unilateral flank incisions were made and right kidneys were excised. The left kidney was subjected to 60 min of ischemia followed by 12, 24, 48, and 72 h of reperfusion. The levels of Scr, blood urea nitrogen (BUN), Wet/Dry ratio, indexes of inflammation, and oxidative stress were assayed. Histological examinations were performed. The protein expression of AMPK, mTOR, LC3-II/LC3-I ratio, and Beclin-1, ULK1 was evaluated by western blotting and immunohistochemistry. Compared to the rats from the sham group, IRI rats showed significantly pulmonary damage after AKI with increased Scr, BUN, Wet/Dry ratio, indexes of inflammation, and oxidative stress. The expression of AMPK, LC3-II/LC3-I ratio, Beclin-1, and ULK1 and were increased, while p62 and mTOR were decreased. In addition, RA treatment significantly attenuated lung injury by promoting autophagy through the activation of the AMPK/mTOR pathway, and 3-MA treatment exhibited adverse effects inversely. Therefore, the activation of the AMPK/mTOR pathway after renal IRI induction could significantly attenuate kidney injury and following AKI-induced ALI by inducing autophagy, which alienates inflammation, oxidative stress, and apoptosis.

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Prenatal opioid exposure may impede the development of adaptive responses to environmental stimuli by altering the stress-sensitive brain circuitry located at the paraventricular nucleus of the hypothalamus (PVH) and locus coeruleus (LC). Corticotropin-releasing factor (CRF) released from neurons in the PVH has emerged as a key molecule to initiate and integrate the stress response. Methadone (Meth) and buprenorphine (Bu) are two major types of synthetic opioid agonists for first-line medication-assisted treatment of opioid (e.g., morphine, Mor) use disorder in pregnant women. No studies have compared the detrimental effects of prenatal exposure to Meth versus Bu on the stress response of their offspring upon reaching adulthood. In this study, we aimed to compare stress-related neuronal activation in the PVH and LC induced by restraint (RST) stress in adult male rat offspring with prenatal exposure to the vehicle (Veh), Bu, Meth, or Mor. CFos-immunoreactive cells were used as an indicator for neuronal activation. We found that RST induced less neuronal activation in the Meth or Mor exposure groups compared with that in the Bu or Veh groups; no significant difference was detected between the Bu and Veh exposure groups. RST-induced neuronal activation was completely prevented by central administration of a CRF receptor antagonist (α-helical CRF_9-41, 10 μg/3 μL) in all exposure groups, suggesting the crucial role of CRF in this stress response. In offspring without RST, central administration of CRF (0.5 μg/3 μL)-induced neuronal activation in the PVH and LC. CRF-induced neuronal activation was lessened in the Meth or Mor exposure groups compared with that in the Bu or Veh groups; no significant difference was detected between the Bu and Veh exposure groups. Moreover, RST- or CRF-induced neuronal activation in the Meth exposure group was comparable with that in the Mor exposure group. Further immunohistochemical analysis revealed that the Meth and Mor exposure groups displayed less CRF neurons in the PVH of offspring with or without RST compared with the Bu or Veh groups. Thus, stress-induced neuronal activation in the PVH and LC was well preserved in adult male rat offspring with prenatal exposure to Bu, but it was substantially lessened in those with prenatal exposure to Meth or Mor. Lowered neuronal activation found in the Meth or Mor exposure groups may be, at least in part, due to the reduction in the density of CRF neurons in the PVH.

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This study aimed to explore the effects of PPAPDC1A on the malignant phenotype of breast cancer (BC) in vivo and in vitro. PPAPDC1A expression was examined in BC tissues and cell lines by real-time polymerase chain reaction and Western blot. In this article, cell proliferation was evaluated by Cell Counting Kit-8 assay and colony formation assay, and cell migration and invasion were evaluated by wound healing assay and transwell assays. Furthermore, in vivo cell growth and pulmonary metastasis experiments were also performed using nude mice. The results showed that compared with normal tissues and cells, the PPAPDC1A expression in BC tissues and cell lines were both significantly increased. The PPAPDC1A targeting sequence significantly inhibited the PPAPDC1A expression and cell proliferation, migration, and invasion. The results of xenograft showed that knockdown of PPAPDC1A inhibited tumor growth and lung metastasis of BC. Then, the Dual-Luciferase Reporter Assay confirmed that miR-598-5p targeted the regulation of PPAPDC1A expression. In addition, the miR-598-5p expression in BC tissues was lower than that in the normal tissues. The rescue experiment showed that PPAPDC1A overexpression reversed the inhibitory effect of miR-598-5p mimic on cell proliferation, migration, and invasion. In conclusion, PPAPDC1A was highly expressed in BC tissues and cell lines, and miR-598-5p inhibited the malignant phenotype of BC by targeting PPAPDC1A.

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Gastric cancer is a type of digestive tract cancer with a high morbidity and mortality, which leads to a major health burden worldwide. More research into the functions of the immune system will improve therapy and survival in gastric cancer patients. We attempted to identify potential biomarkers or targets in gastric cancer via bioinformatical analysis approaches. Three gene expression profile datasets (GSE79973, GSE103236, and GSE118916) of gastric tissue samples were obtained from the Gene Expression Omnibus database. There were 65 overlapping differentially expressed genes (DEGs) identified from three microarrays. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway were carried out for the key functions and pathways enriched in the DEGs. Then, ten hub genes were identified by protein–protein interaction network. In addition, we observed that collagen type V alpha 2 (COL5A2) was linked to gastric cancer prognosis as well as M2 macrophage infiltration. Furthermore, COL5A2 enhanced gastric cancer cell proliferation through the PI3K-AKT signaling pathway and polarized M2 macrophage cells. Therefore, in this study, we found that COL5A2 was associated with the development of gastric cancer which might function as a potential therapeutic target for the disease.

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Nasopharyngeal carcinoma (NPC) is a prevalent malignant tumor worldwide. FKBP3 has been reported to participate in tumorigenesis. Nevertheless, the role and mechanism of FKBP3 in NPC remains unclear. In this study, FKBP3 expression was observed to upregulate in NPC patients and cells. Moreover, knockdown of FKBP3 suppressed cell growth, invasion, and migration in HK1 and C666-1 cells. Mechanically, FKBP3 could enhance the p-p65 expression and activated p65 signaling pathway and increased interleukin-6 (IL-6) expression through enhancing histone deacetylase 2 (HDAC2) expression. In rescued experiment, the overexpression of HDAC2 restored diminished cell growth, invasion, and migration caused by FKBP3 depletion. In summary, the knockdown of FKBP3 suppressed NPC cell growth, invasion and migration, deactivated nuclear factor-κB/IL-6 signaling pathway through inhibiting HDAC2 expression, providing a potential therapeutic strategy for NPC treatment.

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Stanniocalcin 2 (STC2) is identified as a glycosylated peptide hormone and estrogen-responsive gene in cancer cells. STC2 participates in angiogenesis, cell development, cytoprotection, and calcium and phosphate regulation during the development of cancer. The role of STC2 in endometrial cancer (EC) remains unclear. The data from the bioinformatic and immunohistochemical analysis showed that STC2 was upregulated in the EC tissues. The EC cells were treated with 17β-estradiol (E2), and 0.1 μmol/L E2 increased the expression of STC2 in the EC cells. E2 also increased cell viability, promoted proliferation, and inhibited apoptosis of EC. However, the knockdown of STC2 decreased cell viability, reduced proliferation, and promoted apoptosis of E2-stimulated EC. Moreover, silencing of STC2 attenuated E2-induced downregulation of phosphorylated-AMP-activated protein kinase (AMPK) in the EC cells. The loss of STC2 reduced E2-stimulated tumor growth EC in vivo. In conclusion, STC2 deficiency suppressed E2-stimulated proliferation and tumor growth of EC through the activation of AMPK signaling.

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