Unraveling the mystery: a Mendelian randomized exploration of gut microbiota and different types of obesity.

Background: Numerous studies have demonstrated the influence of gut microbiota on the development of obesity. In this study, we utilized Mendelian randomization (MR) analysis to investigate the gut microbiota characteristics among different types of obese patients, aiming to elucidate the underlying mechanisms and provide novel insights for obesity treatment. Methods: Two-sample multivariable Mendelian randomization (MR) analysis was employed to assess causal relationships between gut microbiota and various obesity subtypes. Gut microbiota data were obtained from the international consortium MiBioGen, and data on obese individuals were sourced from the Finnish National Biobank FinnGen. Eligible single-nucleotide polymorphisms (SNPs) were selected as instrumental variables. Various analytical methods, including inverse variance weighted (IVW), MR-Egger regression, weighted median, MR-RAPS, and Lasso regression, were applied. Sensitivity analyses for quality control included MR-Egger intercept tests, Cochran's Q tests, and leave-one-out analyses and others. Results: Mendelian randomization studies revealed distinct gut microbiota profiles among European populations with different obesity subtypes. Following multivariable MR analysis, we found that Ruminococcaceae UCG010 [Odds Ratio (OR): 0.842, 95% confidence interval (CI): 0.766-0.926, Adjusted P value: 0.028] independently reduced the risk of obesity induced by excessive calorie intake, while Butyricimonas [OR: 4.252, 95% CI: 2.177-8.307, Adjusted P value: 0.002] independently increased the risk of medication-induced obesity. For localized adiposity, Pasteurellaceae [OR: 0.213, 95% CI: 0.115-0.395, Adjusted P value: <0.001] acted as a protective factor. In the case of extreme obesity with alveolar hypoventilation, lactobacillus [OR: 0.724, 95% CI: 0.609-0.860, Adjusted P value: 0.035] reduced the risk of its occurrence. Additionally, six gut microbiota may have potential roles in the onset of different types of obesity. Specifically, the Ruminococcus torques group may increase the risk of its occurrence. Desulfovibrio and Catenabacterium may serve as protective factors in the onset of Drug-induced obesity. Oxalobacteraceae, Actinomycetaceae, and Ruminiclostridium 9, on the other hand, could potentially increase the risk of Drug-induced obesity. No evidence of heterogeneity or horizontal pleiotropy among SNPs was found in the above studies (all P values for Q test and MR-Egger intercept > 0.05). Conclusion: Gut microbiota abundance is causally related to obesity, with distinct gut microbiota profiles observed among different obesity subtypes. Four bacterial species, including Ruminococcaceae UCG010, Butyricimonas, Pasteurellaceae and lactobacillus independently influence the development of various types of obesity. Probiotic and prebiotic supplementation may represent a novel approach in future obesity management.

Bacteroidaceae, Bacteroides, and Veillonella: emerging protectors against Graves' disease.

Background: Graves' disease (GD) is the most common cause of hyperthyroidism, and its pathogenesis remains incompletely elucidated. Numerous studies have implicated the gut microbiota in the development of thyroid disorders. This study employs Mendelian randomization analysis to investigate the characteristics of gut microbiota in GD patients, aiming to offer novel insights into the etiology and treatment of Graves' disease. Methods: Two-sample Mendelian randomization (MR) analysis was employed to assess the causal relationship between Graves' disease and the gut microbiota composition. Gut microbiota data were sourced from the international consortium MiBioGen, while Graves' disease data were obtained from FINNGEN. Eligible single nucleotide polymorphisms (SNPs) were selected as instrumental variables. Multiple analysis methods, including inverse variance-weighted (IVW), MR-Egger regression, weighted median, weighted mode, and MR-RAPS, were utilized. Sensitivity analyses were conducted employing MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis as quality control measures. Results: The Mendelian randomization study conducted in a European population revealed a decreased risk of Graves' disease associated with Bacteroidaceae (Odds ratio (OR) [95% confidence interval (CI)]: 0.89 [0.89 ~ 0.90], adjusted P value: <0.001), Bacteroides (OR: [95% CI]: 0.555 [0.437 ~ 0.706], adjusted P value: <0.001), and Veillonella (OR [95% CI]: 0.632 [0.492 ~ 0.811], adjusted P value: 0.016). No significant evidence of heterogeneity, or horizontal pleiotropy was detected. Furthermore, the preliminary MR analysis identified 13 bacterial species including Eubacterium brachy group and Family XIII AD3011 group, exhibiting significant associations with Graves' disease onset, suggesting potential causal effects. Conclusion: A causal relationship exists between gut microbiota and Graves' disease. Bacteroidaceae, Bacteroides, and Veillonella emerge as protective factors against Graves' disease development. Prospective probiotic supplementation may offer a novel avenue for adjunctive treatment in the management of Graves' disease in the future.

Clinical features and risk factors for postoperative recurrence in patients with Cushing's syndrome of different etiologies.

The clinical characteristics of Cushing's syndrome (CS) vary with etiology, and few studies have investigated the risk factors affecting CS recurrence after surgery. This retrospective study involved 202 patients diagnosed with CS between December 2012 and December 2022. The patients were divided into three groups according to etiology: Cushing's disease (CD), adrenocortical adenoma (ACA), and ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS). Of the patients with CS, 41.9% had hypokalemia and 15.0% had hypophosphatemia. The cortisol levels were negatively correlated with blood potassium, blood chlorine, and blood phosphorus. Moreover, 22.4% of patients had an abnormal heart structure, 11.2% had centripetal remodeling, 5.6% had centripetal hypertrophy, and 5.6% had centrifugal hypertrophy. The overall recurrence rate of CS caused by pituitary tumors and adrenal adenoma was 25.7%. The recurrence times were longer in the ACA group versus the CD group, in patients < 50 years of age versus in patients ≥ 50 years old group, and in patients with CD with tumors ≥ 1 cm versus tumors < 1 cm. Age, preoperative cortisol level, postoperative cortisol level, and absolute neutrophil value were closely related to postoperative recurrence, and etiology was an independent predictor of tumor recurrence in patients with CS. The results of this study showed that CS caused by different etiologies showed different clinical manifestations, blood electrolyte characteristics, and that CS could affect patient cardiac structure and function. Etiology is an independent predictor of tumor recurrence in patients with CS.

Causality between sarcopenia and diabetic nephropathy: a bidirectional Mendelian randomization study.

Background and purpose: Observational studies have shown that sarcopenia and diabetic nephropathy (DN), are closely related; however, the causal relationship is unclear. This study aims to address this issue using a bidirectional Mendelian randomization (MR) study. Methodology: We data from genome-wide association studies including appendicular lean mass (n = 244,730), grip strength (right: n = 461,089, left: n = 461026), walking speed (n = 459,915), and DN (3283 cases and 181,704 controls) to conduct a bidirectional MR study. First, we conducted a Forward MR analysis to evaluate the causality of sarcopenia on the risk of DN from the genetic perspective with appendicular lean mass, grip strength, and walking speed as exposure and DN as the outcome. Then, DN as the exposure, we performed a Reverse MR analysis to determine whether DN impacted the appendicular lean mass, grip strength, and walking speed of the appendices. Finally, a series of sensitivity studies, such as heterogeneity tests, pleiotropy evaluations, and Leave-one-out analyses, were conducted to assess the MR analysis's accuracy further. Results: According to a forward MR analysis, a genetically predicted decrease in appendicular lean mass is associated with an increased risk of developing DN risk (inverse variance weighting[IVW]: odd ratio [OR] = 0.863, 95% confidence interval [CI] 0.767-0.971; P = 0.014). According to reverse MR results, grip strength decreased as DN progressed (IVW: right ß = 0.003, 95% CI: - 0.021 to - 0.009, P = 5.116e-06; left ß = 0.003, 95% CI: - 0.024 to - 0.012, P = 7.035e-09). However, the results of the other MR analyses were not statistically different. Conclusion: Notably, our findings suggest that the causal relationship between sarcopenia and DN cannot be generalized. According to analysis of the individual characteristic factors of sarcopenia, reducing in appendicular lean mass increases the risk of developing DN and DN is linked to reduced grip strength. But overall, there is no causal relationship between sarcopenia and DN, because the diagnosis of sarcopenia cannot be determined by one of these factors alone.

The role of lipotoxicity in kidney disease: From molecular mechanisms to therapeutic prospects.

Lipotoxicity is the dysregulation of the lipid environment and/or intracellular composition that leads to accumulation of harmful lipids and ultimately to organelle dysfunction, abnormal activation of intracellular signaling pathways, chronic inflammation and cell death. It plays an important role in the development of acute kidney injury and chronic kidney disease, including diabetic nephropathy, obesity-related glomerulopathy, age-related kidney disease, polycystic kidney disease, and the like. However, the mechanisms of lipid overload and kidney injury remain poorly understood. Herein, we discuss two pivotal aspects of lipotoxic kidney injury. First, we analyzed the mechanism of lipid accumulation in the kidney. Accumulating data indicate that the mechanisms of lipid overload in different kidney diseases are inconsistent. Second, we summarize the multiple mechanisms by which lipotoxic species affect the kidney cell behavior, including oxidative stress, endoplasmic reticulum stress, mitochondrial dysfunction, dysregulated autophagy, and inflammation, highlighting the central role of oxidative stress. Blocking the molecular pathways of lipid accumulation in the kidney and the damage of the kidney by lipid overload may be potential therapeutic targets for kidney disease, and antioxidant drugs may play a pivotal role in the treatment of kidney disease in the future.

Structural Relationships between Counselors' Sense of Calling, Meaning of Work, Living a Calling, and Psychological Burnout.

This study examined the influence of counselors' sense of calling on psychological burnout, mediated by meaning of work and living a calling, based on the work as a calling theory (WCT) and preceding studies. Furthermore, the sequential mediating effects of meaning of work and living a calling were investigated. Data were collected from 420 Korean counselors working in counseling centers located nationwide and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results revealed that a sense of calling negatively impacted psychological burnout. Second, the sense of calling did not affect psychological burnout through the mediation of meaning of work. Third, the sense of calling negatively impacted psychological burnout through the mediation of living a calling. Fourth, the sense of calling negatively affected psychological burnout through the sequential mediation of meaning of work and living a calling. Based on this study's findings, implications can be provided to enhance counselors' professional calling and reduce psychological burnout, thereby aiding them in resolving their psychological issues during counseling practice and providing higher-quality psychological services to clients. Suggestions for improvements and future research are also discussed.

Pathogenesis, clinical features, and treatment of plurihormonal pituitary adenoma.

Plurihormonal pituitary adenoma (PPA) is a type of pituitary tumor capable of producing two or more hormones and usually presents as an aggressive, large adenoma. As yet, its pathogenesis remains unclear. This is the first study to systematically summarize the underlying pathogenesis of PPA. The pathogenesis is related to plurihormonal primordial stem cells, co-transcription factors, hormone co-expression, differential gene expression, and cell transdifferentiation. We conducted a literature review of PPA and analyzed its clinical characteristics. We found that the average age of patients with PPA was approximately 40 years, and most showed only one clinical symptom. The most common manifestation was acromegaly. Currently, PPA is treated with surgical resection. However, recent studies suggest that immunotherapy may be a potentially effective treatment.

Pathogenesis of central nervous system germ cell tumors.

Intracranial germ cell tumors (IGCTs) are clinically rare. They are more common in children and adolescents and the incidence in Asia is higher than in Western countries. Histologically, IGCTs are divided into germinoma and non-germinomatous germ cell tumor (NGGCT). Germinoma is sensitive to radiotherapy and chemotherapy and therefore, patients with germinoma have a good prognosis. However, NGGCTs, especially those with malignant components, are not sensitive to radiotherapy and chemoradiotherapy, leading to a poor prognosis. The pathogenesis of IGCTs is not fully understood. By summarizing previous literature, we found that the occurrence of IGCTs may be related to the following factors: chromosomal instability, MAPK and/or PI3K pathway changes, and DNA hypomethylation in pure germ cell tumors.

A new perspective of hypothalamic disease: Shapiro's syndrome.

Shapiro's syndrome (SS) is characterized by spontaneous periodic hypothermia. It occurs to patients regardless of age or sex. To date, <60 cases have been reported worldwide. Current knowledge of the disease is limited to clinical feature since the pathogenesis and etiology are still controversial. In this review, the clinical characteristics, pathological mechanism, and possible etiology of the syndrome were reviewed to improve the clinical understanding of the disease.

Thyroid storm complicated by corpus callosum infarction in a young patient: A case report and literature review.

RATIONALE: Thyroid storm (TS) is a rare life-threatening hypermetabolic thyrotoxicosis with an incidence of 0.57-0.76/100,000. The coexistence of TS and acute cerebral infarction is rare. Previous studies have shown that hyperthyroidism complicated by cerebral infarction mainly occurs in the intracranial basal ganglia; however, there are no reports of corpus callosum infarction. We report a case of TS complicated by cerebral infarction of the corpus callosum at our hospital. PATIENT CONCERNS: A 31-year-old male patient with a history of hyperthyroidism was admitted to the hospital because of fatigue, palpitations, fever, and profuse sweating accompanied by a mild decrease in the muscle strength of the left limb. Diagnosis of a TS was confirmed by the laboratory test results. The patient's clinical symptoms gradually improved after treatment. However, his left limb muscle strength progressively decreased, and the bilateral pathological signs were positive at the same time. Magnetic resonance imaging (MRI) of the head revealed acute cerebral infarction of the corpus callosum and pons. DIAGNOSIS: The diagnosis was thyroid strom with acute cerebral infarction of the corpus callosum and pons and severe stenosis or occlusion of the basilar artery. INTERVENTIONS: The patient was given 300 mg hydrocortisone intravenously per day, propylthiouracil tablets of 200 mg 3 times a day by nasal feeding, and 20 mg propranolol three times a day by nasal feeding. Aspirin and clopidogrel were administered to prevent platelet aggregation, and atorvastatin calcium was administered to lower lipid levels to stabilize plaques. OUTCOMES: The patient's left limb muscle strength recovered to grade 4+, and he could walk beside the bed with support. Simultaneously, thyroid function was better than before. LESSONS: Careful physical examination should be performed in patients with thyroid storm, and head imaging examination should be improved for the early detection of cerebral infarction.

Mechanism, diagnosis, and treatment of cyclic Cushing's syndrome: A review.

Cushing's syndrome (CS) is caused by hypercortisolemia, leading to the occurrence of characteristic clinical symptoms. A small number of patients with CS have periodic and intermittent increases in cortisol levels, resulting in recurrent episodes of clinical symptoms. Such patients are known as having cyclic CS (CCS). The cortisol secretion cycle of patients with CCS is unpredictable, and laboratory tests often show negative results during the normal cortisol secretion period; therefore, the diagnosis and treatment of the disease are currently difficult. Although the pathogenesis of CCS remains uncertain, recent studies have suggested that it may be closely related to hypothalamic factors, feedback mechanisms, and tumor infarction. Our review summarizes the current state of research on the potential mechanisms, diagnosis, and treatment of CS and provides an outlook for future studies.

ABO blood type and risk of hepatocellular carcinoma: a meta-analysis.

BACKGROUND: ABO blood type is an invariant factor. There is a link between ABO blood type and some malignancies, such as gastric, pancreatic, and skin cancer. The role of ABO blood type in the pathogenesis of hepatocellular carcinoma (HCC) remains controversial. We performed a meta-analysis to explore the relationship between ABO blood type and risk of HCC. METHODS: Literature search was conducted among the PubMed, EMBASE, and Cochrane Library databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS: Seven papers were included. They included 92,847 healthy subjects, 5,463 patients with hepatitis, 294 cirrhotic patients, and 3,322 HCC patients. The proportion of blood type O was significantly lower in HCC patients than healthy subjects (OR = 0.76, 95%CI = 0.66-0.87, P < 0.0001) without any significant heterogeneity (P = 0.55, I2 = 0%). The proportions of blood types A, B, and AB were not significantly different between HCC patients and healthy subjects. The proportion of ABO blood type was not significantly different between patients with HCC and those with hepatitis or cirrhosis. CONCLUSION: HCC patients might have a lower proportion of blood type O than healthy subjects. Among the patients with chronic liver diseases, ABO blood type might not be associated with the risk of HCC.

Hemocoagulase might not control but worsen gastrointestinal bleeding in an elderly patient with type II respiratory failure.

Hemocoagulase has been successfully used for the management of bleeding in patients undergoing surgery. Local spray of hemocoagulase during endoscopic therapy may be effective for the management of gastrointestinal bleeding. In China, intravenous infusion of hemocoagulase is given by some physicians for the treatment of gastrointestinal bleeding. However, the potential adverse events secondary to hemocoagulase, such as hypofibrinogenemia, are poorly recognized. In this paper, we reported an elderly patient with type II respiratory failure in whom hemocoagulase might induce hypofibrinogenemia and further worsen gastrointestinal bleeding. We highlighted that fibrinogen levels should be cautiously monitored in patients receiving hemocoagulase.

Pro-Brain Natriuretic Peptide and Troponin T-Hypersensitivity Levels Correlate With the Severity of Liver Dysfunction in Liver Cirrhosis.

BACKGROUND: Increased pro-brain natriuretic peptide (pro-BNP) or troponin T-hypersensitivity (TnT-HSST) levels are common in liver cirrhosis. We conducted a retrospective observational study aimed to evaluate the correlation of pro-BNP and TnT-HSST levels with the clinical characteristics, laboratory data and in-hospital outcomes of patients with liver cirrhosis. MATERIALS AND METHODS: We selected cirrhotic patients admitted to our hospital between January 2011 and June 2014. All eligible patients had pro-BNP or TnT-HSST data, or both. The pro-BNP and TnT-HSST data were further divided according to the presence of cardiac diseases. RESULTS: The prevalence of pro-BNP level >900pg/mL was 41.72% (63 of 151 patients). The prevalence of TnT-HSST level >0.05ng/mL was 11.22% (45 of 401 patients). In the overall analysis, pro-BNP level significantly correlated with red blood cell (RBC), platelet, ascites, blood urea nitrogen (BUN), creatinine (Cr), Child-Pugh score, model for end-stage liver disease (MELD) score and in-hospital death; TnT-HSST level significantly correlated with white blood cell, ascites, albumin (ALB), BUN, Cr, Child-Pugh score, MELD score and in-hospital death. In patients with cardiac diseases, pro-BNP level significantly correlated with RBC, ascites, BUN, Cr, Child-Pugh score and MELD score; TnT-HSST level significantly correlated with sex, ascites, white blood cell, ALB, BUN, Cr, Child-Pugh score, MELD score and in-hospital death. In patients without cardiac diseases, pro-BNP level significantly correlated with ascites, RBC, platelet, BUN, Cr, MELD score and in-hospital death; TnT-HSST level significantly correlated with age, ascites, RBC, ALB, BUN, Cr, Child-Pugh score, MELD score and in-hospital death. CONCLUSIONS: Pro-BNP and TnT-HSST levels significantly correlated with the severity of liver dysfunction and in-hospital mortality in cirrhosis.

Serum Liver Fibrosis Markers in the Prognosis of Liver Cirrhosis: A Prospective Observational Study.

BACKGROUND The prognostic role of serum liver fibrosis markers in cirrhotic patients remains unclear. We performed a prospective observational study to evaluate the effect of amino-terminal pro-peptide of type III pro-collagen (PIIINP), collagen IV (CIV), laminin (LN), and hyaluronic acid (HA) on the prognosis of liver cirrhosis. MATERIAL AND METHODS All patients who were diagnosed with liver cirrhosis and admitted to our department were prospectively enrolled. PIIINP, CIV, LN, and HA levels were tested. RESULTS Overall, 108 cirrhotic patients were included. Correlation analysis demonstrated that CIV (coefficient r: 0.658, p<0.001; coefficient r: 0.368, p<0.001), LN (coefficient r: 0.450, p<0.001; coefficient r: 0.343, p<0.001), and HA (coefficient r: 0.325, p=0.001; coefficient r: 0.282, p=0.004) levels, but not PIIINP level (coefficient r: 0.081, p=0.414; coefficient r: 0.090, p=0.363), significantly correlated with Child-Pugh and MELD scores. Logistic regression analysis demonstrated that HA (odds ratio=1.00003, 95% confidence interval [CI]=1.000004-1.000056, p=0.022) was significantly associated with the 6-month mortality. Receiver operating characteristics analysis demonstrated that the area under the curve (AUC) of HA for predicting the 6-month mortality was 0.612 (95%CI=0.508-0.709, p=0.1531). CONCLUSIONS CIV, LN, and HA levels were significantly associated with the severity of liver dysfunction, but might be inappropriate for the prognostic assessment of liver cirrhosis.

Endocrine gland­derived vascular endothelial growth factor modulates proliferation, apoptosis and migration in pancreatic cancer cells.

Endocrine gland­derived vascular endothelial growth factor (EG­VEGF) is a newly cloned factor that selectively acts on the endothelium of endocrine gland cells. EG­VEGF was previously identified as an important cytokine, involved in the modulation of apoptosis in pancreatic cancer cell lines. The present study examined the effects of EG­VEGF proliferation and migration, in pancreatic cancer cells. To determine the potential for EG­VEGF as a therapeutic target for pancreatic cancer, the expression of EG­VEGF were measured in pancreatic cancer tissue, and the association between its expression and the clinicopathological characteristics of the pancreatic cancer patients was determined. The results of the present study suggest that EG­VEGF may act as a novel tumor gene in pancreatic cancer. EG­VEGF was rarely expressed in the normal pancreatic tissue, but was highly expressed in the pancreatic cancer tissue. These data suggest that EG­VEGF may be a cancer­specific, and possibly tissue­specific, survival factor in the pancreas. In the Mia PaCa­2 pancreatic cancer cell line, EG­VEGF was shown to promote proliferation and cellular invasion, and modulate the phosphorylation of mitogen­activated protein kinase, a modulator for the malignant phenotype.

KAI1 inhibits lymphangiogenesis and lymphatic metastasis of pancreatic cancer in vivo.

BACKGROUND: Several studies have shown that KAI1 inhibits tumor metastasis, but its mechanism is not clear. The present study aimed to determine the role of KAI1 in lymphatic metastasis, specifically in pancreatic cancer. METHODS: The KAI1 gene was transfected into the pancreatic cancer cell line MIA PaCa-2 and PANC-1 by using liposomes and selected by G418, and the protein was measured by Western blotting. After successful infection, the cell growth curve was studied by MTT, vascular endothelial growth factor C (VEGF-C) secretion by pancreatic cancer cell were measured by ELISA. The KAI1 and pCMV transfected MIA PaCa-2 cells were renamed as MIA PaCa-2-K and MIA PaCa-2-p. These two kinds of cells were injected into the subcuticular layer of nude mice; both tumor growth and metastasis through the lymphatic nodes were assessed. Lymphangiogenesis in tumors was measured by immunohistochemistry. RESULTS: The VEGF-C secretion was significantly reduced in MIA PaCa-2 cells compared with PANC-1 cells after being transfected with the KAI1 gene. The growth rate of subcutaneous tumors was similar after the injection of MIA PaCa-2-K, MIA PaCa-2, and MIA PaCa-2-p. MIA PaCa-2-K tumors showed slower lymphangiogenesis and lymph node metastasis compared with MIA PaCa-2 and MIA PaCa-2-p tumors. CONCLUSION: The overexpression of KAI1 inhibits the lymphangiogenesis and lymph node metastasis of MIA PaCa-2 pancreatic tumors.

Generation of CTL responses against pancreatic cancer in vitro using dendritic cells co-transfected with MUC4 and survivin RNA.

Pancreatic cancer (PC) is one of the most devastating human malignancies without effective therapies. Tumor vaccine based on RNA-transfected dendritic cells (DCs) has emerged as an alternative therapeutic approach for a variety of human cancers including advanced PC. In the present study we compared the cytotoxic T lymphocyte (CTL) responses against PC cells in vitro, which were induced by DCs co-transfected with two mRNAs of tumor associated-antigens (TAA) MUC4 and survivin, versus DCs transfected with a single mRNA encoding either MUC4 or survivin. DCs co-transfected with two TAA mRNAs were found to induce stronger CTL responses against PC target cells in vitro, compared with the DCs transfected with a single mRNA. Moreover, the antigen-specific CTL responses were MHC class I-restricted. These results provide an experimental foundation for further clinical investigations of DC vaccines encoding multiple TAA epitopes for metastatic PC.

Endocrine glands-derived vascular endothelial growth factor protects pancreatic cancer cells from apoptosis via upregulation of the myeloid cell leukemia-1 protein.

Endocrine glands-derived vascular endothelial growth factor (EG-VEGF, also termed as Prok1)--a novel cytokine that selectively acts on the endothelial cells of endocrine glands--was recently reported to be involved in the regulation of tumor cell growth and survival. However, its roles in the regulation of pancreatic cancer progression remain unclear. In this report, we investigated the suppressive effects of EG-VEGF on pancreatic cancer cell apoptosis and the relevant mechanisms. By using reverse-transcriptase polymerase chain reaction (RT-PCR) we found that the Mia PaCa II cells of the pancreatic cancer cell line express the mRNAs of both EG-VEGF (Prok1) and its receptors. EG-VEGF protects pancreatic cancer cells from apoptosis through upregulation of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein of the bcl-2 family. Treatment of pancreatic cancer cells with EG-VEGF results in the rapid phosphorylation of mitogen-activated protein kinase (MAPK), STAT3, and AKT, which are involved in the upregulation of Mcl-1 expression. EG-VEGF (Prok1) protects Mia PaCa II cells from apoptosis through G protein-coupled receptor (GPR)-induced activation of multiple signal pathways, and hence can be a novel target for pancreatic cancer therapy.

KAI1 is a potential target for anti-metastasis in pancreatic cancer cells.

AIM: To investigate whether KAI1, as a metastasis suppressor gene, is associated with invasive and metastatic ability of pancreatic cancer cells. METHODS: KAI1 gene was transfected into pancreatic cancer cell line MiaPaCa II by liposomes selected with G418. Expression of transfected cells was measured by Western blotting, immunofluorescence and immunocytochemistry. Tumor cell invasion and metastatic ability were detected through gelatinase activity and reconstituted basement membrane (Matrigel) assay. pCMV-KAI1 was directly injected into the heterotopic human pancreatic adenocarcinoma successfully established in the groin of BALB/C nude mice, by subcutaneous injection of MiaPaCa II pancreatic cancer cells. The statistical analysis between groups was determined by Student's two tailed t test. RESULTS: By Western blotting, MiaPaCa II cells transfected by KAI1 gene indicated KAI1 expression at approximately 29.1 kDa. Cytoplasm staining was positive and uniformly spread in transfected cancer cells, using immunohistochemistry and immunofluorescence. The most obvious difference was present after 30 h (MiaPaca II 43.6 +/- 9.42, pCMV-MiaPaca II 44.8 +/- 8.56, pCMV-KAI1-MiaPaca II 22.0 +/- 4.69, P < 0.05). Gelatinolysis revealed a wider and clearer band of gelatinolytic activity in non-transfected than in transfected cells (MiaPaCa II cells 30.8 +/- 0.57, transfected cells 28.1 +/- 0.65, P < 0.05). In vivo tumor growth rates of KAI1 transfectants with KAI1-Lipofectamine 1.22 +/- 0.31 in A group were lower than control 4.61 +/- 1.98 and pCMV-KAI 11.67 +/- 0.81. Analyses of metastases with and without KAI1 transfection in mice were different in liver and lung between controls 1.62 +/- 0.39, 0.45 +/- 0.09, pCMV-KAI 1.01 +/- 0.27, 0.33 +/- 0.09 and KAI1-Lipofectamine 0.99 +/- 0.21, 0.30 +/- 0.09 respectively (P < 0.05). CONCLUSION: High expression of KAI1 gene was found in transfected MiaPaCa II human pancreatic cancer cells with lower metastatic ability. KAI1 gene plays an important role in inhibiting metastasis of pancreatic cancer after direct injection into pancreatic adenocarcinoma. These results show that the suppressed invasion and motor function of pancreatic cancer cells may be a key reason why the KAI1 gene controls pancreatic cancer cell metastasis.