Application of a combined clinical prediction model based on enhanced T1-weighted image(T1WI) full volume histogram in peripheral nerve invasion (PNI) and lymphatic vessel invasion (LVI) in rectal cancer.

PURPOSE: This study aims to use a combined clinical prediction model based on enhanced T1-weighted image(T1WI) full volume histogram to predict preoperative peripheral nerve invasion (PNI) and lymphatic vessel invasion (LVI) in rectal cancer. METHODS: We included a total of 68 PNI patients and 80 LVI patients who underwent surgical resection and pathological confirmation of rectal cancer. According to the PNI/LVI status, patients were divided into PNI positive group (n = 39), the PNI negative group (n = 29), LVI positive group (n = 48), and the LVI negative group (n = 32). External validation included a total of 42 patients with nerve and vascular invasion in patients with surgically resected and pathologically confirmed rectal cancer at another healthcare facility, with a PNI positive group (n = 32) and a PNI-negative group (n = 10) as well as an LVI positive group (n = 35) and LVI-negative group (n = 7). All patients underwent 3.0T magnetic resonance T1WI enhanced scanning. We use Firevoxel software to delineate the region of interest (ROI), extract histogram parameters, and perform univariate analysis, LASSO regression, and multivariate logistic regression analysis in sequence to screen for the best predictive factors. Then, we constructed a clinical prediction model and plotted it into a column chart for personalized prediction. Finally, we evaluate the performance and clinical practicality of the model based on the area under curve (AUC), calibration curve, and decision curve. RESULTS: Multivariate logistic regression analysis found that variance and the 75th percentile were independent risk factors for PNI, while maximum and variance were independent risk factors for LVI. The clinical prediction model constructed based on the above factors has an AUC of 0.734 (95% CI: 0.591-0.878) for PNI in the training set and 0.731 (95% CI: 0.509-0.952) in the validation set; The training set AUC of LVI is 0.701 (95% CI: 0.561-0.841), and the validation set AUC is 0.685 (95% CI: 0.439-0.932). External validation showed an AUC of 0.722 (95% CI: 0.565-0.878) for PNI; and an AUC of 0.706 (95% CI: 0.481-0.931) for LVI. CONCLUSIONS: This study indicates that the combination of enhanced T1WI full volume histogram and clinical prediction model can be used to predict the perineural and lymphovascular invasion status of rectal cancer before surgery, providing valuable reference information for clinical diagnosis.

Thyroid Metastases from Breast Cancer Case Report and Literature Review.

BACKGROUND: Thyroid metastasis arising from primary breast cancer is a rare phenomenon, with only a handful of cases documented in both national and international literature. The management approach and prognosis of this occurrence have sparked debates and uncertainties. CASE PRESENTATION: Herein, we report the case of a 55-year-old woman with breast cancer. She previously underwent extensive excision of the breast lesion with adjuvant chemotherapy and endocrine therapy. After 9 years, she presented with neck discomfort and examination suggested right thyroid metastasis and lymph node metastasis in the neck. Imaging showed pulmonary and bone metastases. Furthermore, the patient received endocrine therapy. After 7 months of follow- up, the patient survived without any new distant metastases. Thyroid metastases originating from breast cancer often unfold with a subtle, intricate nature, making early detection challenging. They tend to emerge inconspicuously, intertwining with widespread systemic metastases, hinting at a less favorable prognosis. CONCLUSION: Given the unusual clinical indicators, identifying heterochronic thyroid metastases in patients with tumors poses a distinct challenge, requiring clinicians to navigate the follow-up process with heightened sensitivity. The key lies in timely detection and early intervention, factors that can significantly enhance the overall quality of life for patients.

Cytochrome b561 regulates iron metabolism by activating the Akt/mTOR pathway to promote Breast Cancer Cells proliferation.

Breast cancer (BC) is the leading cause of cancer-related mortality in women, necessitating the development of novel therapeutic targets. While cytochrome b561 (CYB561) expression is associated with poor prognosis in BC, the precise role of CYB561 in BC and its potential mechanisms remain unclear. In the present study, we found that CYB561 plays an essential role in BC growth. CYB561 expression was up-regulated in surgically resected cancerous tissues and in six BC cell lines. Lentivirus-mediated CYB561 knockdown in BC cells significantly reduced their proliferation, migration, and invasiveness. CYB561 participates in the regulation of iron metabolism in BC. CYB561 knockdown reduced total iron content, increased ferrous iron content, and down-regulated the expression of proteins associated with iron metabolism (transferrin receptor 1, divalent metal transporter 1, and ferritin heavy chain 1). Conversely, up-regulation of CYB561 through co-incubation with exogenous iron (ferric ammonium citrate) produced contrary outcomes. Additionally, CYB561 activated the protein kinase B/mammalian target of rapamycin (Akt/mTOR) signaling pathway in BC cells. Down-regulation of CYB561 expression inhibited the Akt/mTOR signaling pathway activity. The application of an mTOR agonist (MHY1485) rescued this negative effect, as well as the inhibitory effect of CYB561 knockdown on cell proliferation. Importantly, the dual mTOR inhibitor MLN0128 (50 nM, 48 h) down-regulated CYB561 expression and the iron metabolism-related proteins transferrin receptor, divalent metal transporter 1, and ferritin heavy chain 1, whereas the mTOR agonist MHY1485 rescued the down-regulation of CYB561 knockdown on iron metabolism-related proteins. We conclude that CYB561 promotes the proliferation of BC cells by regulating iron metabolism through the activation of the Akt/mTOR signaling pathway.

Phosphorylation of PBK/TOPK Tyr74 by JAK2 promotes Burkitt lymphoma tumor growth.

Burkitt lymphoma (BL), which is characterized by high invasiveness, is a subgroup of non-Hodgkin lymphoma. Although BL is regarded as a highly curable disease, especially for children, some patients unfortunately still do not respond adequately. The understanding of the etiology and molecular mechanisms of BL is still limited, and targeted therapies are still lacking. Here, we found that T-LAK cell-derived protein kinase (TOPK) and phosphorylated Janus kinase 2 (p-JAK2) are highly expressed in the tissues of BL patients. We report that TOPK directly binds to and is phosphorylated at Tyr74 by JAK2. Histone H3, one of the downstream targets of TOPK, is also phosphorylated in vivo and in vitro. Furthermore, we report that the phosphorylation of TOPK at Tyr74 by JAK2 plays a vital role in the proliferation of BL cells and promotes BL tumorigenesis in vivo. Phosphorylation of TOPK at Tyr74 by JAK2 enhances the stability of TOPK. Collectively, our results suggest that the JAK2/TOPK/histone H3 axis plays a key role in the proliferation of BL cells and BL tumorigenesis in vivo.

Spontaneous Rupture and Hemorrhage of WON: A Case Report.

Background: Pancreatic pseudocysts are characterized by the leakage of pancreatic juice caused by various reasons, which leads to pancreatic juice accumulates around the pancreas, and stimulates the greater omentum and other tissues to form an area of fibrotic loculated effusion with an integrated capsule. Approximately, one-third of patients experienced recurrent pancreatic juice leakage, compression symptoms, infection, and bleeding, which requires surgical intervention, but spontaneous rupture cases are extremely rare. Case presentation: We here present the case of 40-year-old male who presented with abdominal pain and vomiting for two days and 10 h, respectively. He had a history of chronic pancreatitis and pseudocysts. The symptoms of abdominal pain worsened in the second day. Laboratory tests showed a progressive decrease in hemoglobin. Then, emergency pancreatoduodenectomy was performed. Intraoperative exploration found a small blood clot in the abdominal cavity and a hematoma that had formed in the intestinal cavity and retroperitoneum. Conclusion: This case showed that pseudocysts of the pancreas can rupture under certain circumstances, leading to intraperitoneal bleeding and hematoma formation, which can endanger the life of the patient. And surgical treatment can be the first choice for hemorrhagic pseudocysts.

Momordica charantia Exosome-Like Nanoparticles Exert Neuroprotective Effects Against Ischemic Brain Injury via Inhibiting Matrix Metalloproteinase 9 and Activating the AKT/GSK3ß Signaling Pathway.

Plant exosome-like nanoparticles (ELNs) have shown great potential in treating tumor and inflammatory diseases, but the neuroprotective effect of plant ELNs remains unknown. In the present study, we isolated and characterized novel ELNs from Momordica charantia (MC) and investigated their neuroprotective effects against cerebral ischemia-reperfusion injury. In the present study, MC-ELNs were isolated by ultracentrifugation and characterized. Male Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) and MC-ELN injection intravenously. The integrity of the blood-brain barrier (BBB) was examined by Evans blue staining and with the expression of matrix metalloproteinase 9 (MMP-9), claudin-5, and ZO-1. Neuronal apoptosis was evaluated by TUNEL and the expression of apoptotic proteins including Bcl2, Bax, and cleaved caspase 3. The major discoveries include: 1) Dil-labeled MC-ELNs were identified in the infarct area; 2) MC-ELN treatment significantly ameliorated BBB disruption, decreased infarct sizes, and reduced neurological deficit scores; 3) MC-ELN treatment obviously downregulated the expression of MMP-9 and upregulated the expression of ZO-1 and claudin-5. Small RNA-sequencing revealed that MC-ELN-derived miRNA5266 reduced MMP-9 expression. Furthermore, MC-ELN treatment significantly upregulated the AKT/GSK3ß signaling pathway and attenuated neuronal apoptosis in HT22 cells. Taken together, these findings indicate that MC-ELNs attenuate ischemia-reperfusion-induced damage to the BBB and inhibit neuronal apoptosis probably via the upregulation of the AKT/GSK3ß signaling pathway.

KAP1 phosphorylation promotes the survival of neural stem cells after ischemia/reperfusion by maintaining the stability of PCNA.

AIMS: To explore the function of phosphorylation of KAP1 (p-KAP1) at the serine-824 site (S824) in the proliferation and apoptosis of endogenous neural stem cells (NSCs) after cerebral ischemic/reperfusion (I/R). METHODS: The apoptosis and proliferation of C17.2 cells transfected with the p-KAP1-expression plasmids and the expression of proliferation cell nuclear antigen (PCNA) and p-KAP1 were detected by immunofluorescence and Western blotting after the Oxygen Glucose deprivation/reperfusion model (OGD/R). The interaction of p-KAP1 and CUL4A with PCNA was analyzed by immunoprecipitation. In the rats MCAO model, we performed the adeno-associated virus (AAV) 2/9 gene delivery of p-KAP1 mutants to verify the proliferation of endogenous NSCs and the colocalization of PCNA and CUL4A by immunofluorescence. RESULTS: The level of p-KAP1 was significantly down-regulated in the stroke model in vivo and in vitro. Simulated p-KAP1(S824) significantly increased the proliferation of C17.2 cells and the expression of PCNA after OGD/R. Simulated p-KAP1(S824) enhanced the binding of p-KAP1 and PCNA and decreased the interaction between PCNA and CUL4A in C17.2 cells subjected to OGD/R. The AAV2/9-mediated p-KAP1(S824) increased endogenous NSCs proliferation, PCNA expression, p-KAP1 binding to PCNA, and improved neurological function in the rat MCAO model. CONCLUSIONS: Our findings confirmed that simulated p-KAP1(S824) improved the survival and proliferation of endogenous NSCs. The underlying mechanism is that highly expressed p-KAP1(S824) promotes binding to PCNA, and inhibits the binding of CUL4A to PCNA. This reduced CUL4A-mediated ubiquitination degradation to increase the stability of PCNA and promote the survival and proliferation of NSCs.

Expression and clinical prognostic value of CYB561 in breast cancer.

PURPOSE: The expression of cytochrome B561 (CYB561) and its role in breast cancer (BC) prognosis remain unclear. We analyzed the differential expression and prognostic value of CYB561 using online databases and a clinical cohort through bioinformatics and immunohistochemistry. METHODS: The differential expression of CYB561 and its association with BC were analyzed using the tumor immune estimation resource (TIMER), gene expression profiling interaction analysis2 (GEPIA2), Human Protein Atlas, Cancer Cell Line Encyclopedia, and Kaplan-Meier Plotter website. Important pathways of CYB561 enrichment were explored using gene set enrichment analysis. Immunohistochemistry detected CYB561 expression in normal breast, breast hyperplasia, ductal carcinoma in situ (DCIS), para-cancer, and invasive BC groups. Association between CYB561 expression and BC prognosis was analyzed using Kaplan-Meier and Cox regression analyses. RESULTS: CYB561 mRNA expression was higher in GEPIA and TIMER BC patients than in para-cancer tissues. CYB561 was expressed in the glandular epithelium and myoepithelium, with positive localization in the cytoplasm and cell membrane. CYB561 protein expression significantly differed among the groups. CYB561 expression was correlated with ERBB2/HER2 and infiltrating CD4+ T cells in GEPIA and TIMER BC patients and associated with HER2 status, histological grade, and molecular subtypes in the clinical cohort but not related to tumor-infiltrating lymphocytes. CYB561 mRNA overexpression predicted reduced recurrence-free survival and overall survival in BC. Patients with CYB561 expression had significantly reduced overall survival and increased risk of death. CONCLUSION: CYB561 can serve as an effective clinical prognostic biomarker for BC.

Male-specific long non-coding RNA testis-specific transcript, Y-linked 15 promotes gastric cancer cell growth by regulating Wnt family member 1/ß-catenin signaling by sponging microRNA let-7a-5p.

The present study is aimed to investigate the regulatory effects and related mechanism of long non-coding RNA testis-specific transcript, Y-linked 15 (TTTY15) in gastric carcinoma (GC) cell proliferation, migration, invasion, apoptosis and epithelial-mesenchymal transition (EMT). TTTY15 expression in GC tissue samples and cells was detected by quantitative real-time PCR (qRT-PCR), and the correlation between TTTY15 expression and GC clinicopathological indicators was analyzed. Cell counting kit-8 (CCK-8), BrdU, flow cytometry and Transwell assays were performed for detecting GC cell proliferation, migration, invasion and apoptosis. Western blot was performed for detecting the expressions of EMT-associated proteins (N-cadherin and E-cadherin), Wnt family member 1 (Wnt1) protein and ß-catenin protein. Bioinformatics analysis was conducted to predict, and RNA immunoprecipitation (RIP) assay and dual-luciferase reporter gene assay were performed to verify the targeted relationships of microRNA let-7a-5p (let-7a-5p) with TTTY15 and Wnt1 mRNA 3'UTR. It was found that TTTY15 expression was significantly up-regulated in GC tissues and cells, and was associated with advanced TNM stage and poor tumor differentiation. TTTY15 overexpression promoted GC cell proliferation, migration and invasion, the expressions of N-cadherin, Wnt1 and ß-catenin protein, and inhibited the apoptosis and E-cadherin expression, while knocking down TTTY15 had the opposite effects. TTTY15 directly targeted let-7a-5p and negatively regulated its expression. Wnt1 was the target gene of let-7a-5p, and TTTY15 could indirectly and positively regulate Wnt1 expression. In conclusion, TTTY15 promotes GC progression, by regulating the let-7a-5p/Wnt1 axis to activate the Wnt/ß-catenin pathway.

CD20-positive extranodal NK/T cell lymphoma: clinicopathologic and prognostic features.

Extranodal natural killer (NK)/T cell lymphoma (ENKTCL) with aberrant CD20 expression is extremely rare. Here, we describe the clinicopathologic features of 11 CD20-positive ENKTCLs from three institutions in China along with a literature review. Membranous expression of CD20 was identified in 1.29% (11/851) of ENKTCLs. CD20-positive ENKTCLs primarily occurred in extra-nasal sites (72.2%, 13/18) rather than in the nasal cavity (27.8%, 5/18). Most evaluated patients (71.4%, 10/14) presented ENKTCL at advanced stage IV. The percentage of CD20-positive tumor cells ranged from 20 to 90%, and the CD20 staining intensity was dimmer in tumor cells than in normal B cells. Among four cases with multiple biopsies, three cases showed discordant expression of CD20 between the disseminated and primary lesions. All evaluated cases were negative for other B cell markers, including PAX5, CD79a, and CD19, except for one case that showed focally positive for CD79a. Patients with CD20-positive ENKTCL more frequently had advanced diseases (stage III/IV: 70% vs 17%, p = 0.001), with older age (median age at diagnosis: 60 years vs. 43.5 years, p = 0.006) and had inferior outcome (median survival: 18.7 moths vs 36.0 moths, p = 0.017) compared with CD20-negative cases. Four nonsynonymous single nucleotide variants (C > T) and one stop-gain mutation (C > T) in the exonic region of CD20 gene (MS4A1) were detected in one of seven cases with target region next-generation sequencing. Thus, ENKTCL with aberrant CD20 expression is rare, tends to occur in older patients, and is characterized by a highly aggressive clinical course and poor outcomes. The mechanism underlying the expression of CD20 in ENKTC still remains unknown.

A comparison between triplet and doublet chemotherapy in improving the survival of patients with advanced gastric cancer: a systematic review and meta-analysis.

BACKGROUND: Chemotherapy can improve the survival of patients with advanced gastric cancer. However, whether triplet chemotherapy can further improve the survival of patients with advanced gastric cancer compared with doublet chemotherapy remains controversial. This study reviewed and updated all published and eligible randomized controlled trials (RCTs) to compare the efficacy, prognosis, and toxicity of triplet chemotherapy with doublet chemotherapy in patients with advanced gastric cancer. METHODS: RCTs on first-line chemotherapy in advanced gastric cancer on PubMed, Embase, and the Cochrane Register of Controlled Trials and all abstracts from the annual meetings of the European Society for Medical Oncology (ESMO) and the American Society of Clinical Oncology conferences up to October 2018 were searched. The primary outcome was overall survival, while the secondary outcomes were progression-free survival (PFS), time to progress (TTP), objective response rate (ORR), and toxicity. RESULTS: Our analysis included 23 RCTs involving 4540 patients and 8 types of triplet and doublet chemotherapy regimens, and systematic review and meta-analysis revealed that triplet chemotherapy was superior compared with doublet chemotherapy in terms of improving median OS (HR = 0.92; 95% CI, 0.86-0.98; P = 0.02) and PFS (HR = 0.82; 95% CI, 0.69-0.97; P = 0.02) and TTP (HR = 0.92; 95% CI, 0.86-0.98; P = 0.02) and ORR (OR = 1.21; 95% CI, 1.12-1.31; P < 0.0001) among overall populations. Compared with doublet chemotherapy, subgroup analysis indicated that OS improved with fluoropyrimidine-based (HR = 0.80; 95% CI, 0.66-0.96; P = 0.02), platinum-based (HR = 0.75; 95% CI, 0.57-0.99; P = 0.04), and other drug-based triplet (HR = 0.79; 95% CI, 0.69-0.90; P = 0.0006) chemotherapies while not with anthracycline-based (HR = 0.70; 95% CI, 0.42-1.15; P = 0.16), mitomycin-based (HR = 0.81; 95% CI, 0.47-1.39; P = 0.44), taxane-based (HR = 0.91; 95% CI, 0.81-1.01; P = 0.07), and irinotecan-based triplet (HR = 1.01; 95% CI, 0.82-1.24; P = 0.94) chemotherapies. For different patients, compared with doublet chemotherapy, triplet chemotherapy improved OS (HR = 0.89; 95% CI, 0.81-0.99; P = 0.03) among Western patients but did not improve (HR = 0.96; 95% CI, 0.86-1.07; P = 0.47) that among Asian patients. CONCLUSIONS: Compared with doublet chemotherapy, triplet chemotherapy improved OS, PFS, TTP, and ORR in patients with advanced gastric cancer in the population overall, and improved OS in Western but not in Asian patients.

Effects of Pulse Parameters on Weld Microstructure and Mechanical Properties of Extra Pulse Current Aided Laser Welded 2219 Aluminum Alloy Joints.

In order to expand the application range of laser welding and improve weld quality, an extra pulse current was used to aid laser-welded 2219 aluminum alloy, and the effects of pulse current parameters on the weld microstructure and mechanical properties were investigated. The effect mechanisms of the pulse current interactions with the weld pool were evaluated. The results indicated that the coarse dendritic structure in the weld zone changed to a fine equiaxed structure using an extra pulse current, and the pulse parameters, including medium peak current, relatively high pulse frequency, and low pulse duty ratio benefited to improving the weld structure. The effect mechanisms of the pulse current were mainly ascribed to the magnetic pinch effect, thermal effect, and electromigration effect caused by the pulse current. The effect of the pulse parameters on the mechanical properties of welded joints were consistent with that of the weld microstructure. The tensile strength and elongation of the optimal pulse current-aided laser-welded joint increased by 16.4% and 105%, respectively, compared with autogenous laser welding.

Combined resection of the right liver lobe and retrohepatic inferior vena cava to treat hepatic alveolar echinococcosis: A case report.

RATIONALE: Hepatic alveolar echinococcosis (HAE) is a potentially fatal and chronically progressive infestation that is caused by the multivesicular metacestode of Echinococcus multilocularis (EM). HAE behaves like a malignant tumor and has been referred to as "worm cancer." The main treatment method for HAE is surgical resection. PATIENT CONCERNS: We present a 41-year-old Tibetan alveolar echinococcosis (AE) patient with AE lesions invading the right liver lobe and retrohepatic inferior vena cava (RHIVC). DIAGNOSES: The patient was diagnosed with HAE based on results obtained from ultrasound examination, computed tomography, liver 3-dimensional reconstruction, serology tests, clinical presentation, and surgical exploration. The final pathology report confirmed the diagnosis as HAE. INTERVENTIONS: A radical surgery that combined resection of the liver and RHIVC was performed successfully. OUTCOMES: The patient had an uneventful postoperative recovery and a good prognosis. LESSONS: When lesions of the liver significantly violate the RHIVC, resecting the RHIVC without reconstruction may be considered if possible.

Identification of an Association of TNFAIP3 Polymorphisms With Matrix Metalloproteinase Expression in Fibroblasts in an Integrative Study of Systemic Sclerosis-Associated Genetic and Environmental Factors.

OBJECTIVE: Systemic sclerosis (SSc) is a fibrotic disease attributed to both genetic susceptibility and environmental factors. This study was undertaken to investigate the associations between SSc-associated genetic variants and the expression of extracellular matrix (ECM) genes in human fibroblasts stimulated with silica particles in time-course and dose-response experiments. METHODS: A total of 200 fibroblast strains were examined for ECM gene expression after stimulation with silica particles. The fibroblasts were genetically profiled using Immunochip assays and then subjected to whole-genome genotype imputation. Associations of genotypes and gene expression were first analyzed in a Caucasian cohort and then validated in a meta-analysis combining the results from Caucasian, African American, and Hispanic subjects. A linear mixed model for longitudinal data analysis was used to identify genetic variants associated with the expression of ECM genes, and the associations were validated by using a haplotype-based longitudinal association test on regions that included the loci identified. RESULTS: The single-nucleotide polymorphism rs58905141 in TNFAIP3 was consistently associated with time-course and/or dose-response expression of MMP3 and MMP1 in the fibroblasts stimulated with silica particles in both the analysis of Caucasian subjects only and the meta-analysis. Results of the haplotype-based analysis validated the association signals. CONCLUSION: Our findings indicate that a genetic variant of TNFAIP3 is strongly associated with the silica-induced profibrotic response of fibroblasts. In silico functional analysis based on the ENCODE database revealed that rs58905141 might affect the binding activities of the transcription factors for TNFAIP3. This is the first genome-wide study of interactions between genetic and environmental factors in a complex SSc fibroblast model.

Clinical epidemiology of gastric cancer in Hehuang valley of China: a 10-year epidemiological study of gastric cancer.

AIM: To investigate the clinical epidemiological characteristics of gastric cancer in the Hehuang valley, China, to provide a reference for treatment and prevention of regional gastric cancer. METHODS: Between February 2003 and February 2013, the records of 2419 patients with gastric cancer were included in this study. The patient's characteristics, histological and pathological features, as well as the dietary habits of the patients, were investigated. RESULTS: The clinical data showed that adenocarcinoma was the leading histological type of gastric cancer in this area. Characteristics of gastric cancer in different ethnic groups and age showed that the 60.55-65.50 years group showed the high incidence of gastric cancer in all ethnic groups. There were more male gastric cancer patients than female. Intestinal was the most common type of gastric cancer in the Hehuang valley. There was no significant difference in the proportion of sex in terms of Helicobacter pylori infection. The impact of dietary habits on gastric cancer showed that regular consumption of fried or grilled food, consumption of high-salt, high-fat and spicy food and drinking strong Boiled brick-tea were three important factors associated with gastric cancer in males and females. CONCLUSION: Differences existed in race, sex, and age of patients according to the epidemiology of gastric cancer in the Hehuang valley. Moreover, dietary habits was also an important factor contributing to gastric cancer.

BRAF exon 15 T1799A mutation is common in melanocytic nevi, but less prevalent in cutaneous malignant melanoma, in Chinese Han.

Frequent somatic mutations of BRAF (v-raf murine sarcoma viral oncogene homolog B) exon T1799A, which are implicated in the initial events of promutagenic cellular proliferation, are detected in both malignant melanomas (MM) and melanocytic nevi (MN). Most of the data regarding BRAF exon T1799A mutation have been from Caucasian cohorts, and a comprehensive screening of a homogeneous population is lacking. A total of 379 cases of MN and 195 cases of MM were collected from Chinese Han living in three geographical regions in China, i.e., northeast, southwest, and northwest China. BRAF exon T1799A mutation was detected by PCR and sequencing from microdissected tumors. In all, 59.8% cases of MN harbored BRAF exon T1799A mutation. Samples from regions with high UV exposure had higher detection rates than regions with lower UV exposure (73.5, 67.0, and 38.9%, respectively; χ(2) = 31.674, P = 1.59E-7). There were no differences in mutation rates between congenital and acquired MN; however, acquired MN with advanced age of onset had a higher mutation rate than those with younger age of onset (χ(2) = 13.23, P = 0.02). In all, 15.0% cases of MM harbored the BRAF mutation. The mutation rate in MM was not affected by region, histological type, gender, pattern of UV exposure, and age. The study suggests that the mutation is not necessarily associated with malignant transformation.

Attenuation of fibrosis in vitro and in vivo with SPARC siRNA.

INTRODUCTION: SPARC is a matricellular protein, which, along with other extracellular matrix components including collagens, is commonly over-expressed in fibrotic diseases. The purpose of this study was to examine whether inhibition of SPARC can regulate collagen expression in vitro and in vivo, and subsequently attenuate fibrotic stimulation by bleomycin in mouse skin and lungs. METHODS: In in vitro studies, skin fibroblasts obtained from a Tgfbr1 knock-in mouse (TBR1CA; Cre-ER) were transfected with SPARC siRNA. Gene and protein expressions of the Col1a2 and the Ctgf were examined by real-time RT-PCR and Western blotting, respectively. In in vivo studies, C57BL/6 mice were induced for skin and lung fibrosis by bleomycin and followed by SPARC siRNA treatment through subcutaneous injection and intratracheal instillation, respectively. The pathological changes of skin and lungs were assessed by hematoxylin and eosin and Masson's trichrome stains. The expression changes of collagen in the tissues were assessed by real-time RT-PCR and non-crosslinked fibrillar collagen content assays. RESULTS: SPARC siRNA significantly reduced gene and protein expression of collagen type 1 in fibroblasts obtained from the TBR1CA; Cre-ER mouse that was induced for constitutively active TGF-beta receptor I. Skin and lung fibrosis induced by bleomycin was markedly reduced by treatment with SPARC siRNA. The anti-fibrotic effect of SPARC siRNA in vivo was accompanied by an inhibition of Ctgf expression in these same tissues. CONCLUSIONS: Specific inhibition of SPARC effectively reduced fibrotic changes in vitro and in vivo. SPARC inhibition may represent a potential therapeutic approach to fibrotic diseases.

Attenuation of collagen production with small interfering RNA of SPARC in cultured fibroblasts from the skin of patients with scleroderma.

OBJECTIVE: Recently, it was observed that SPARC (secreted protein, acidic and rich in cysteine) is overexpressed in the fibroblasts of skin biopsy specimens obtained from patients with systemic sclerosis (SSc; scleroderma), and that specific inhibition of SPARC expression in normal human fibroblasts attenuated the profibrotic effect of transforming growth factor beta (TGFbeta). The purpose of this study was to examine whether inhibition of SPARC with small interfering RNA (siRNA) can be used to ameliorate the overproduction of major extracellular matrix components in SSc fibroblasts. METHODS: Fibroblasts obtained from biopsy specimens of the unaffected skin of 3 patients with diffuse SSc and 3 age- and sex-matched healthy controls were cultured and transfected with SPARC siRNA. Before and after transfection, real-time quantitative reverse transcription-polymerase chain reaction, immunostaining, and Western blotting were used to examine the transcription and/or protein levels of SPARC, connective tissue growth factor (CTGF), type I collagen, type II collagen, TGFbeta receptor 1 (TGFbetaR1), and Smad3. Student's paired t-tests were used to determine the significance of the results. RESULTS: SSc fibroblasts showed overexpression of SPARC, COL1A2, COL3A1, and CTGF, which is consistent with an activated fibroblast phenotype. Upon inhibition of SPARC with siRNA, these activated SSc fibroblasts showed decreased gene expression of COL1A2, COL3A1, and CTGF (43%, 54%, and 58%, respectively). In addition, the overproduction of type I collagen protein in SSc fibroblasts was inhibited and was shown to parallel levels of SPARC expression. In contrast, the expression of TGFBR1 and Smad3 did not change significantly nor was the level of phosphorylation of Smad3 reduced upon SPARC siRNA silencing in unstimulated cultured SSc fibroblasts. CONCLUSION: Overproduction of collagens in SSc skin fibroblasts can be attenuated through SPARC silencing. This inhibition may be associated either with direct interaction between SPARC and collagens or with inhibition of CTGF, which is a downstream effector of TGFbeta signaling. However, SPARC silencing in SSc fibroblasts appears not to be associated with TGFBR1- and Smad3-dependent processes. Application of SPARC silencing represents a potential therapeutic approach to SSc.

Small interfering RNA inhibition of SPARC attenuates the profibrotic effect of transforming growth factor beta1 in cultured normal human fibroblasts.

OBJECTIVE: SPARC (secreted protein, acidic and rich in cysteine), or osteonectin, is a matricellular protein. Recently, it was observed to be overexpressed in fibroblasts obtained from the skin of patients with scleroderma, as well as in different tissues from patients with several other fibrotic disorders. Moreover, a genetic polymorphism in SPARC has been associated with susceptibility to scleroderma. Transforming growth factor beta1 (TGFbeta1) is a profibrotic cytokine that stimulates excessive collagen production in patients with scleroderma or other fibrotic diseases. The purpose of this study was to examine whether specific inhibition of SPARC can influence the expression of type I collagen and ameliorate the profibrotic activity of TGFbeta1 on normal human fibroblasts. METHODS: Fibroblasts obtained from the skin of 4 healthy individuals were cultured and transfected with SPARC small interfering RNA (siRNA). TGFbeta was used as a fibrosis stimulus in cultured fibroblasts. Real-time quantitative reverse transcriptase-polymerase chain reaction and Western blotting were used to measure transcription and protein levels of SPARC and type I collagen, respectively. RESULTS: The fibroblasts transfected with SPARC siRNA showed decreased expression of both SPARC and type I collagen. Exogenous TGFbeta1 induced increased expression of both SPARC and type I collagen in cultured normal human fibroblasts, but this response was significantly blunted in the fibroblasts transfected with SPARC siRNA. CONCLUSION: TGFbeta1 can induce increased expression of both SPARC and type I collagen. Specific inhibition of SPARC led to decreased expression of type I collagen and attenuated the profibrotic effect of TGFbeta1 in cultured normal human fibroblasts. Use of siRNA to silence SPARC represents a potential therapeutic approach to fibrotic disorders such as scleroderma.