In early pregnancy, fetal skin wounds can heal quickly and undergo a transition period from scarless healing to scar formation. The aim of the present study was to identify potential biomarkers associated with scarless repair of cleft lips, in order to determine the intrinsic factors leading to scar formation in embryonic tissue. A stable model of cleft lip was established using microsurgery by constructing a wedge‑shaped cleft lip‑like defect in fetal rats at gestational age (GA) 16.5 and GA18.5. The GA16.5 and GA18.5 groups were used to model scarless healing and scar formation, respectively. The fetuses were returned to the uterus following surgery, then removed 72 h after the procedure. Macroscopic observation of the cleft defect and histological examination were carried out. Reverse transcription‑quantitative (RT‑q) PCR and parallel reaction monitoring (PRM) were used to detect mRNA and protein expression levels, respectively. The upper‑left lip completely healed 72 h after surgery in the GA16.5 group of fetal rats. However, this was not the case in the GA18.5 group. Histological examination indicated new follicles visible under the epidermis of the scarless group (GA16.5). Scarring was visible on the upper‑left cleft lip wound of the fetal rats in the GA18.5 group. The expression of some growth and pro‑inflammatory factors, including TNF‑α, were also different between two groups. Label‑free quantification was used to identified differentially expressed proteins and five differentially expressed proteins (Smad4, Fabp5, S100a4, S100a8 and S100a9) were identified. The relative expression of these molecules at the mRNA and protein levels were measured using RT‑qPCR and PRM. These molecules may represent potential biomarkers for the scarless repair of fetal rat cleft lip wounds.

The present study aimed to investigate the molecular pathology of Waardenburg syndrome type II in three families, in order to provide genetic diagnosis and hereditary counseling for family members. Relevant clinical examinations were conducted on the probands of the three pedigrees. Peripheral blood samples of the probands and related family members were collected and genomic DNA was extracted. The coding sequences of paired box 3 (PAX3), microphthalmia‑associated transcription factor (MITF), sex‑determining region Y‑box 10 (SOX10) and snail family zinc finger 2 (SNAI2) were analyzed by polymerase chain reaction and DNA sequencing. The heterozygous mutation, c.649_651delAGA in exon 7 of the MITF gene was detected in the proband and all patients of pedigree 1; however, no pathological mutation of the relevant genes (MITF, SNAI2, SOX10 or PAX3) was detected in pedigrees 2 and 3. The heterozygous mutation c.649_651delAGA in exon 7 of the MITF gene is therefore considered the disease‑causing mutation in pedigree 1. However, there are novel disease‑causing genes in Waardenburg syndrome type II, which require further research.

Hyperoxia may cause pulmonary fibrosis in neonates and is characterized by the epithelial‑to‑mesenchymal transition (EMT) of alveolar epithelial cells. The placental growth factor (PLGF) gene is a member of the vascular endothelial growth factor family and is highly expressed in lung tissues that have been exposed to hyperoxia. The aim of the present study was to assess the role of PLGF in the EMT of lung tissue. Lung tissue exhibiting low PLGF expression was obtained by injecting rats exposed to hyperoxia with a PLGF‑silencing lentiviral plasmid. Western blot analysis and immunohistochemistry revealed that expression levels of the EMT‑related protein epithelial‑cadherin were increased, whereas its inhibitor protein zinc‑finger E‑box binding homeobox 2 was decreased in these rats. These data demonstrated that PLGF silencing may significantly mitigate hyperoxia‑induced EMT in rat lung tissue. Additionally, an increase in phosphorylated‑p38 MAPK protein expression indicated that PLGF may be able to regulate hyperoxia‑induced lung injury in rats via the p38 MAPK pathway.

Chaperone‑mediated autophagy (CMA) is a selective type of autophagy whereby a specific subset of intracellular proteins is targeted to the lysosome for degradation. The present study investigated the mechanisms underlying the response and resistance to 5‑fluorouracil (5‑FU) in colorectal cancer (CRC) cell lines. In engineered 5‑FU‑resistant CRC cell lines, a significant elevation of lysosome‑associated membrane protein 2A (LAMP2A), which is the key molecule in the CMA pathway, was identified. High expression of LAMP2A was found to be responsible for 5‑FU resistance and to enhance PLD2 expression through the activation of NF‑κB pathway. Accordingly, loss or gain of function of LAMP2A in 5‑FU‑resistant CRC cells rendered them sensitive or resistant to 5‑FU, respectively. Taken together, the results of the present study suggested that chemoresistance in patients with CRC may be mediated by enhancing CMA. Thus, CMA is a promising predictor of chemosensitivity to 5‑FU treatment and anti‑CMA therapy may be a novel therapeutic option for patients with CRC.

Inflammation serves a key role in chronic obstructive pulmonary disease (COPD). However, changes in the immune profiles of patients with COPD remain unclear. The present prospective observational study aimed to determine the expression profiles of immune cells and inflammatory factors of patients with COPD and healthy controls, and to analyze the relationship between immune profiles and smoking history. A total of 140 subjects were enrolled in the present study between September 2018 and April 2019 at West China Hospital of Sichuan University (Chengdu, China). These included 87 patients with stable COPD and 24 patients with acute exacerbated COPD, as well as 29 healthy controls. Baseline characteristics were recorded during the screening period, and levels of immune cells were examined using flow cytometry. In addition, levels of inflammatory factors were measured using ELISAs. The results revealed increased expression of the CD64+/CD14+ mononuclear phagocyte system (MPS) and CD16+CD66+ neutrophils, and decreased expression of CD3+CD4+ T cells and CD3+ CD8+ T cells (all P<0.05) in the peripheral blood of patients with COPD and smokers relative to non‑smoking controls. In addition, significant differences were observed in protein levels of IL‑6, IL‑1β, TNF‑α, TGF‑α, IFN‑γ, IL‑8, IL‑17A and CRP among the three groups (all P<0.05). Furthermore, the IL‑17A, TNF and NF‑κB signaling pathways were found to serve a key role in the inflammatory network of COPD. Pearson's correlation analysis revealed a positive correlation between CD3+T lymphocyte counts and pulmonary function, and a negative correlation with smoking and exacerbations. Furthermore, neutrophils and MPS were negatively associated with pulmonary function, and IL‑8 was positively associated with cough. There was also a negative association between CRP and IL‑17A with pulmonary function but a positive correlation with symptoms and exacerbation. Club cell secretory protein was also negatively associated with emphysema parameters. In conclusion, the present findings revealed significant differences in profiles of immune factors among patients with COPD, smokers and non‑smoking controls and their association with clinical characteristics. The clinical trial registration number of the present study is: ChiCTR1800015700 (registered with http://www.chictr.org.cn/index.aspx, 2018/04/16).

Ganoderma lucidum has featured in traditional Chinese medicine for >1,000 years. Ganoderma polysaccharides (GL-PS), a major active ingredient in Ganoderma, confer immune regulation, antitumor effects and significant antioxidant effects. The aim of the present study was to investigate the efficacy and mechanism of GL‑PS‑associated inhibition of ultraviolet B (UVB)‑induced photoaging in human fibroblasts in vitro. Primary human skin fibroblasts were cultured, and a fibroblast photoaging model was built through exposure to UVB. Cell viability was measured by MTT assay. Aged cells were stained using a senescence‑associated β-galactosidase staining (SA‑β‑gal) kit. ELISA kits were used to analyze matrix metalloproteinase (MMP) ‑1 and C‑telopeptides of Type I collagen (CICP) protein levels in cellular supernatant. ROS levels were quantified by flow cytometry. Cells exposed to UVB had decreased cell viability, increased aged cells, decreased CICP protein expression, increased MMP‑1 protein expression, and increased cellular ROS levels compared with non‑exposed cells. However, cells exposed to UVB and treated with 10, 20 and 40 µg/ml GL‑PS demonstrated increased cell viability, decreased aged cells, increased CICP protein expression, decreased MMP‑1 protein expression, and decreased cellular ROS levels compared with UVB exposed/GL‑PS untreated cells. These results demonstrate that GL‑PS protects fibroblasts against photoaging by eliminating UVB‑induced ROS. This finding indicates GL‑PS treatment may serve as a novel strategy for antiphotoaging.

Long non-coding RNA (lncRNA), transcripts of >200 bp in length that do not appear to exhibit any coding capacity, are important in the occurrence and development of cancer, cardiovascular and neurological diseases. However, effects of lncRNAs on photo‑aging remain to be elucidated. To explore the potential effects of the lncRNA metastasis‑associated lung adenocarcinoma transcript 1 (MALAT1) on photo‑aging in fibroblasts, MALAT1 expression was silenced in fibroblasts using small interference RNA. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to examine MALAT1 expression in normal and silenced fibroblasts following irradiation with 60 mJ/cm2 ultraviolet B (UVB) and an ELISA assay was used to identify matrix metalloproteinase‑1 (MMP‑1) content in the cellular supernatant. A β-galactosidase kit was applied to measure the number of senescent cells and a western blot assay was used to detect extracellular signal‑regulated kinase (ERK), c‑Jun N‑terminal kinase (JNK) and p38 phosphorylation levels. RT‑qPCR was additionally used to detect changes in MALAT1 expression following suppression of UVB‑induced reactive oxygen species (ROS) generation with N‑acetyl‑L‑cysteine (NAC). Fibroblasts irradiated with 60 mJ/cm2 UVB demonstrated increased MALAT1 expression, MMP‑1 secretory volume and number of senescent cells, and greater levels of ERK, p38 and JNK phosphorylation. Following silencing of MALAT1 expression in photo‑aged fibroblasts, decreases were observed in MMP‑1 secretory volume, number of senescent cells and phosphorylation levels of ERK. NAC reduced ROS content, however, it did not affect MALAT1 expression. Therefore, it was concluded that MALAT1 may participate in UVB‑induced photo‑aging via regulation of the ERK/mitogen‑activated protein kinase signaling pathway and UVB‑induced MALAT1 expression is independent of ROS generation.

Human gingival fibroblasts (HGFs) are responsible for connective tissue repair and scarring, and are exposed to mechanical forces under physiological and pathological conditions. The exact mechanisms underlying gingival tissue reconstruction under mechanical forces remain unclear. The present study aimfed to investigate the effects of mechanical forces on the proliferation and extracellular matrix synthesis in HGFs by establishing a 3‑dimensional (3D) HGF culture model using poly(lactide‑co‑glycolide) (PLGA) scaffolds. HGFs were cultured in 3D PLGA scaffolds and a mechanical force of 0, 5, 15, 25 or 35 g/cm2 was applied to HGFs for 24 h. A mechanical force of 25 g/cm2 induced the highest proliferation rate, and thus was selected for subsequent experiments. Cell viability was determined using the MTT assay at 0, 24, 48 and 72 h. The expression levels of type I collagen (COL‑1) and matrix metallopeptidase (MMP)‑1 were examined by reverse transcription‑quantitative polymerase chain reaction and ELISA, and transforming growth factor (TGF)‑β expression was evaluated by ELISA. The application of mechanical force on HGFs cultured on the 3D PLGA scaffolds resulted in a significant increase in cell proliferation and COL‑1 expression, as well as a decrease in MMP‑1 expression. A TGF‑β1 inhibitor was also applied, which attenuated the effects of mechanical force on HGF proliferation, and COL‑1 and MMP‑1 expression, thus suggesting that TGF‑β signaling pathways may mediate the mechanical force‑induced alterations observed in HGFs. In conclusion, these findings helped to clarify the mechanisms underlying mechanical force‑induced HGF proliferation and ECM synthesis, which may promote the development of targeted therapeutics to treat various diseases, including gingival atrophy caused by orthodontic treatment.

Camurati-Engelmann disease (CED) is a rare autosomal dominant bone disorder caused by a mutation in transforming growth factor β1 (TGFβ1). The present study aimed to identify a Chinese family with suspected CED based on the clinical symptoms, including pain in extremities, waddling gait, muscle weakness, cortical thickening of the diaphysis of the long bones, and sclerosis of the skull, facial bone, and pelvis. Molecular analysis revealed the presence of the p.Glu169Lys (E169K) mutation in exon 2 of TGFβ1 in patients when compared with the controls. Therefore, the Chinese family was diagnosed with CED due to the presence of the E169K mutation. The present study emphasized the importance of clinical and genetic evidence for the diagnosis of CED. The data presented in the present study are of significance to clinicians, as well as genetic counselors, in the prenatal screening of CED.

As a heat shock protein 90 inhibitor, 17-allylamino-17‑demethoxygeldanamycin (17-AAG) has been studied in numerous types of cancer, however the effects of 17-AAG on apoptosis and the cell cycle of H446 cells remain unclear. In the current study, the MTT method was used to evaluate the inhibitory effects of different durations and doses of 17‑AAG treatment on the proliferation of H446 cells. The cells were stained with Annexin-fluorescein isothiocyanate/propidium iodide and measured by flow cytometry, and the gene and protein expression levels of signal transducer and activator of transcription 3 (STAT3), survivin, cyclin D1, cyt‑C, caspase 9 and caspase 3 were determined by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. The results indicated that with treatment with 1.25‑20 mg/l 17‑AAG for 24 and 48 h, significant inhibition of H446 cell proliferation was observed in a time‑ and dose‑dependent manner. With treatment of 3.125, 6.25 and 12.5 mg/l 17‑AAG for 48 h, significant apoptosis and cell cycle arrest was observed. The results indicated that the gene and protein expression levels of STAT3, survivin and cyclin D1 were downregulated, and cyt‑C, caspase 9 and caspase 3 were upregulated by 17‑AAG in a dose-dependent manner when the cells were treated with 3.125 and 6.25 mg/l 17-AAG for 48 h. The results indicated that 17‑AAG is able to inhibit the cell proliferation, induce apoptosis and G2/M arrest and downregulate the gene and protein expression levels of STAT3, survivin and cyclin D1, and upregulate gene and protein expression of cyt‑C, caspase 9, caspase 3.