FTO demethylates YAP mRNA promoting oral squamous cell carcinoma tumorigenesis.

N6-methyladenosine (m6A) is the most common internal reversible modification of mRNA, which occurs on the N6 nitrogen of adenosine. Fat mass and obesity-associated (FTO) is a demethylase that erases m6A modification and has recently been linked to cancer. Herein, we explored the role of FTO in oral squamous cell carcinoma (OSCC). High FTO mRNA and protein levels were observed in OSCC cell lines and tissues as compared to normal controls. OSCC patients with high FTO displayed larger tumor size, higher TNM stage, poorer differentiation, and shorter survival time than those with low FTO. Stable knockdown of FTO inhibited OSCC cell viability, colony formation, and tumor growth. Further, FTO depletion increased YAP1 m6A modification at mRNA 3'-untranslated region, accelerating the degradation of YAP1 mRNA, a well-documented oncogene promoting OSCC progression. Importantly, nucleocytoplasmic shuttling of FTO is critical for YAP1 mRNA demethylation and decay following YTHDF2 reading and recognition. Our results highlight the role of FTO in regulating YAP1 mRNA stability, and targeting of FTO/YAP1 axis may be a promising intervention for OSCC patients.

A novel method in the removal of impacted mandibular third molar: buccal drainage.

Food impaction after impacted mandibular third molar extraction is a serious problem that should not be ignored. Incomplete suturing of the distal incision in the conventional method is the main cause of food impaction and delayed wound healing. The present study introduces a novel suture and drainage technology that requires hermetic suturing of the distal incision and rubber drainage for buccal drainage. 76 patients with horizontally/mesially impacted third molars (bilateral) were enrolled in this prospective study. An impacted tooth on one side of each patient was extracted by occlusal drainage using the conventional method, whereas the other side tooth was extracted by buccal drainage using the novel method. The differences in wound healing, facial swelling, bleeding and dry socket between the two sides of each patient were compared postoperatively, and the trends for patient selection of the surgical method were also compared. The results indicated that buccal drainage had obvious advantages in wound healing and reduced the risk of postoperative bleeding, and most patients preferred this technique; there were no significant differences in postoperative facial swelling or pain. Thus, buccal drainage can solve the problem of long-term food impaction induced by traditional incision postoperatively and is worthy of clinical promotion.

Platelet-derived growth factor BB enhances osteoclast formation and osteoclast precursor cell chemotaxis.

Enhanced osteoclast formation increases bone resorption, which triggers bone remodeling. Platelet-derived growth factor BB (PDGF-BB) enhances precursor cell homing, angiogenesis, and bone healing, and thereby could also treat osteoporosis. However, the effect of PDGF-BB on osteoclast formation is not fully understood. We investigated whether exogenous recombinant PDGF-BB directly affects osteoclast formation and osteoclast precursor cell chemotaxis. The murine monocyte-macrophage cell line RAW264.7 and bone-marrow-derived macrophages were cultured with recombinant mouse PDGF-BB with or without a platelet-derived growth factor receptor ß inhibitor (AG-1295) or a Janus kinase 2 inhibitor (AG-490) to analyze the effect on osteoclastogenesis in vitro. PDGF-BB with or without AG-490 or AG-1295 was locally administrated in the mandibular fracture of 16-week-old Sprague Dawley rats (n = 18) for 1-2 weeks to analyze the effect on osteoclastogenesis in vivo. The effect of the treatments on osteoclast formation, osteoclast precursor cell migration, and expression of osteoclastogenic signaling molecules was analyzed. PDGF-BB enhanced osteoclast formation both in vitro and in vivo, but AG-490 and AG-1295 inhibited this effect. PDGF-BB enhanced phosphorylation of extracellular-signal-regulated kinase 1/2 (ERK1/2), Akt, and signal transducer and activator of transcription 3 (STAT3) in RAW264.7 cells. AG-490 inhibited PDGF-BB-induced STAT3 phosphorylation. PDGF-BB enhanced RAW264.7 cell migration and gene expression of osteoclastogenic signaling molecules (i.e., nuclear factor of activated T cells 1, dendrocyte-expressed seven transmembrane protein, and B-cell lymphoma 2), and treatment with AG-1295, AG-490, or S3I-201 (a STAT3 inhibitor) reduced this effect. PDGF-BB enhanced osteoclast formation, osteoclast precursor cell chemotaxis, and phosphorylation of STAT3, Akt, and ERK1/2. but AG-1295 and AG-490 reduced this effect. These findings reflect the complexity of PDGF-BB in bone biology.

Lysophosphatidic acid upregulates connective tissue growth factor expression in osteoblasts through the GPCR/PKC and PKA pathways.

Lysophosphatidic acid (LPA) is an efficient, bioactive phospholipid involved in various biological processes. In this study, LPA-induced connective tissue growth factor (CTGF/CCN2) expression and the underlying mechanisms were investigated using the MC3T3-E1 cell line. The MC3T3-E1 cells were stimulated with an inhibitor of LPA receptors, an activator and inhibitor of protein kinase C (PKC) and protein kinase A (PKA) for indicated periods of time. RT-qPCR and western blot analyses were used to measure the expression levels of CCN2. Immunofluorescence staining was used to observe the translocation of PKC. The mRNA expression level of CCN2 was increased following stimulation of the cells with LPA; LPA transiently induced the mRNA expression of CCN2; maximum expression levels were observed 2 h following stimulation with LPA. This increase was accompanied by CCN2 protein synthesis. LPA receptor1/3 was inhibited by Ki16425, a specific inhibitor of LPA1/3; as a result, the LPA-induced increase in CCN2 expression was abrogated. LPA also induced the membrane translocation of PKC and enhanced PKC activity in the osteoblasts. Pre-treatment of the osteoblasts with staurosporine prevented the increase in CCN2 expression by induced by LPA, and the activation of PKC by phorbol 12-myristate 13-acetate (PMA) enhanced CCN2 expression, indicating that the PKC pathway is involved in the LPA-induced increase in CCN2 expression. The interference of PKA signaling also led to the induction of CCN2 expresion by LPA. These data indicate that LPA increases CCN2 expression through the activation of PKC and PKA. Thus, the regulatory functions of the PKC and PKA pathways are implicated in the LPA-induced increase in CCN2 expression.

Multiple Inoculations of Bone Marrow Stromal Cells into Beta-Tricalcium Phosphate/Chitosan Scaffolds Enhances the Formation and Reconstruction of New Bone.

PURPOSE: To compare the effects of different cell inoculation strategies on cellular attachment and viability as well as on osteogenic differentiation capacity and subsequent bone graft functionality after implantation of cellularized scaffolds in a mandibular defect rabbit model. MATERIALS AND METHODS: Bone marrow stromal cells (BMSCs) were inoculated into the scaffolds of beta-tricalcium phosphate/chitosan (ß-TCP/CS) either once or multiple times and their efficiency assessed based on cell viability, initial seeding efficiency, alkaline phosphatase activity in cell lysates, mineralization activity in cryosections of cell-seeded scaffolds by von Kossa staining, and osteogenic differentiation on reverse transcriptase polymerase chain reaction. RESULTS: Compared with one-time inoculation of BMSCs, multiple inoculations led to higher cell viability, increased proliferation, more homogeneous distribution in the scaffold, better in vitro osteogenic differentiation, and improved in vivo bone repair in a rabbit model of mandibular defect. CONCLUSION: Multiple inoculations have many advantages over the one-time inoculation method and should be further researched for bone tissue engineering.

Prognostic factors in the surgical treatment of caudate lobe hepatocellular carcinoma.

AIM: To evaluate the short- and long-term outcomes of liver resection for caudate lobe hepatocellular carcinoma (HCC). METHODS: We retrospectively analyzed 114 consecutive patients with HCC, originating from the caudate lobe, who underwent resection between January 2001 and January 2007. Univariate and multivariate analyses were performed on several clinicopathologic variables to determine the factors affecting long-term outcome and intrahepatic recurrence. RESULTS: Overall mortality and morbidity were 0% and 18%, respectively. After a median follow-up of 31 mo (interquartile range, 11-66 mo), tumor recurrence had occurred in 76 patients (66.7%). The 1-, 3-, and 5-year disease-free survival rates were 65.7%, 38.1%, and 18.4%, respectively. The 1-, 3-, and 5-year overall survival rates were 76.1%, 54.7%, and 31.8%, respectively. Univariate analysis showed that subsegmental location of the tumor (45.7% vs 16.2%, P = 0.01), liver cirrhosis (12.3% vs 47.9%, P = 0.03), surgical margin (18.5% vs 54.6%, P = 0.04), vascular invasion (37.9% vs 23.2%, P = 0.04) and extended caudate resection (42.1% vs 15.4%, P = 0.04) were related to poorer long-term survival. Multivariate analysis showed that only subsegmental location of the tumor, liver cirrhosis and surgical margin were significant independent prognostic factors. CONCLUSION: Hepatectomy was an effective treatment for HCC in the caudate lobe. The subsegmental location of the tumor, liver cirrhosis and surgical margin affected long-term survival.

[Effect of the amount of portal blood stasis removal on endotoxemia and liver function after liver transplantation].

OBJECTIVE: To investigate the influence of the amount of portal blood stasis removal on endotoxemia and liver function after liver transplantation. METHODS: Forty-seven patients who received liver transplantation from February 2006 to November 2007 were divided into 2 groups according to the amount of portal blood stasis removal during operation: group A (n = 26) 50 ml and group B (n = 21) 200 ml of portal blood stasis removal respectively. The levels of plasma endotoxin, D-lactate, tumor necrosis factor-alpha, interleukin-6, liver function and blood coagulation were examined and analyzed. RESULTS: Under the condition of no significant difference in sex, age, primary liver diseases and Child-pugh's classification, cold ischemic time, total operation and anhepatic time, operation methods, volume of blood loss and transfusion, and all preoperative observations. Most of observations showed the restoration of the patients in group B was better than that in group A. The plasma levels of endotoxin, D-lactate, tumor necrosis factor-alpha, interleukin-6, alanine aminotransferase, aspartate aminotransferase, prothrombin time and activated partial thromboplastin time in group B were significantly lower than those in group A (P < 0.05). The level of plasma prealbumin in group B was significantly higher than that in group A (P < 0.05). CONCLUSIONS: The removal of 200 ml portal blood stasis leads to a better results than that of 50 ml, and it can help alleviate endotoxemia and facilitate the restoration of the liver function after liver transplantation.

[The effect of portal blood stasis on lung and renal injury induced by hepatic ischemia reperfusion in a rabbit model].

OBJECTIVE: To investigate the effect and mechanism of portal blood stasis on lung and renal injury induced by hepatic ischemia reperfusion. METHODS: A rabbit hepatic ischemia reperfusion injury model was established by hepatic portal occlusion and in situ hypothermic irrigation for 30 min. Twenty-four New Zealand white rabbits were employed and randomly divided into 3 groups equally by different dosage of portal blood stasis removal: group A5 (5 ml blood removal), group A10 (10 ml blood removal),and group B (no blood removal). Eight rabbits were served as controls with no hepatic portal occlusion and hypothermic irrigation. After reperfusion 4 h serum endotoxin content, tumor necrosis factor-alpha (TNF-alpha), urea nitrogen (BUN), and creatinine (Cr) were examined respectively, meantime lung and kidney tissues were sampled to determine the content of malondialdehyde (MDA), superoxide dismutase (SOD), the pathology, and wet to dry weight ratio, broncho-alveolar lavage fluid protein content in lung tissues. RESULTS: Removing portal blood stasis ameliorated lung and renal injury as shown by decreasing the level of serum endotoxin, TNF-alpha, BUN, Cr, wet to dry weight ratio, broncho-alveolar lavage fluid protein content, MDA, SOD. TNF-alpha, Cr, broncho-alveolar lavage fluid protein content in lung tissues and MDA in kidney tissue in group A5 were significantly reduced compared with those in group B (P < 0.05), while in lung tissue in group A10 were also markedly reduced (P < 0.05). The activation of SOD in group A5 were significantly increased (P < 0.05). CONCLUSIONS: Removal of portal blood stasis before the resume of splanchnic circulation may ameliorate the lung and renal injury induced by hepatic ischemia reperfusion. The possible mechanism may be that portal blood stasis removal reduces endotoxin absorption, and further decreases production of serum TNF-alpha.

Clinical features of solitary necrotic nodule of the liver.

BACKGROUND: Solitary necrotic nodule of the liver is a rare nonmalignant lesion. The present study aimed to clarify the clinical features of the disease. METHOD: The medical records of 51 patients with histologically confirmed solitary necrotic nodule of the liver who received surgical resection at our institution were retrospectively reviewed. RESULTS: Solitary necrotic nodule of the liver was found mainly in males (68.6%, 35/51), and patients ranged in age from 5 to 69 years with a mean of 45.3. Most of the patients (72.5%) had no significant symptoms, with negative results for the serum tumor markers alpha-fetoprotein, carbohydrate antigen 19-9 and carcinoembryonic antigen. The mean diameter of the nodule was 23 mm (range 10-55 mm). Compared with ultrasonographic and computed tomography findings, the specific features of magnetic resonance imaging were more helpful for differential diagnosis of the disease. CONCLUSIONS: Solitary necrotic nodule of the liver is a rare nonmalignant lesion, showing no notable symptoms and potential complications. The pathological change of the disease is not significant over a lifetime. Conservative treatment and clinical follow-up are recommended.

Clinical features of hepatic angiomyolipoma.

BACKGROUND: Hepatic angiomyolipoma (HAML) is a rare hepatic mesenchymal tumor. This study was designed to explore its clinical features. METHODS: Clinical data from 26 patients who had been pathologically confirmed with HAML and had received surgical resection at our hospital were analyzed retrospectively. RESULTS: HAML was seen more frequently in females (18/26) in this series, and most of the patients presented no significant symptoms except for one who had a spontaneous rupture hemorrhage. Serum alpha-fetoprotein (AFP), carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were negative in all patients. Imaging presentations were diverse. Pre-operative diagnosis was made in only 3 patients. Pathological study showed that the tumor was composed of adipose tissue, smooth muscle and blood vessels in different proportions. One patient showed hepatic vessel invasion. HMB-45 immunohistochemical staining was positive in all tumors. All patients underwent surgical resection without significant complications. Except for one patient who died 14 months after operation because of recurrent disease, no tumor recurrence was observed in the remaining 25 patients during a 2-3 years follow-up. CONCLUSIONS: Pre-operative diagnosis of HAML is difficult. There are potential risks of spontaneous rupture and malignant transformation. Surgical resection is the treatment of choice for HAML.

Risk factors for intrahepatic cholangiocarcinoma: a case-control study in China.

AIM: To carry out a hospital-based case-control study to investigate risk factors for intrahepatic cholangiocarcinoma (ICC) in China. METHODS: A total of 312 ICC cases and 438 matched controls were included in the study. The presence of diabetes mellitus, hypertension, hepatolithiasis, primary sclerosing cholangitis, liver fluke infection (Clonorchis sinensis), was investigated through clinical records. Blood from all participants was tested for hepatitis B surface antigen (HBsAg) and anti-HCV antibodies. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using conditional logistic regression. RESULTS: Compared with controls, ICC patients had a higher prevalence of HBsAg seropositivity (48.4% vs 9.6%, P<0.000), and hepatolithiasis (5.4% vs 1.1%, P=0.001). By multivariate analysis, the significant risk factors for development of ICC were HBsAg seropositivity (adjusted OR, 8.876, 95% CI, 5.973-13.192), and hepatolithiasis (adjusted OR, 5.765, 95% CI, 1.972-16.851). The prevalence of anti-HCV seropositivity, diabetes mellitus, hypertension, cigarette smoking, and alcohol consumption were not significantly different between cases and controls. CONCLUSION: These findings suggest that HBV infection and hepatolithiasis are strong risk factors for development of ICC in China.

Combined hepatocellular carcinoma and cholangiocarcinoma: a case report and review of the literature.

BACKGROUND: Combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) is a rare histopathologic form of primary liver cancer. We report a case of cHCC-CC and review the literature. METHOD: The clinicopathological features of a 61-year-old male were retrospectively analyzed. RESULTS: Hepatocellular carcinoma (HCC) was preoperatively considered on the basis of clinical findings resembling those associated with HCC. Hepatectomy was therefore performed. Microscopically, the specimen displayed histological features of cHCC-CC. The patient has remained alive after follow-up for 3 months without evidence of recurrence and metastasis. CONCLUSION: It is difficult to make a correct preoperative diagnosis of cHCC-CC and hepatic resection is the treatment of choice.