The Fast Spiking Subpopulation of Striatal Neurons Coding for Temporal Cognition of Movements.

Background: Timing dysfunctions occur in a number of neurological and psychiatric disorders such as Parkinson's disease, obsessive-compulsive disorder, autism and attention-deficit-hyperactivity disorder. Several lines of evidence show that disrupted timing processing is involved in specific fronto-striatal abnormalities. The striatum encodes reinforcement learning and procedural motion, and consequently is required to represent temporal information precisely, which then guides actions in proper sequence. Previous studies highlighted the temporal scaling property of timing-relevant striatal neurons; however, it is still unknown how this is accomplished over short temporal latencies, such as the sub-seconds to seconds range. Methods: We designed a task with a series of timing behaviors that required rats to reproduce a fixed duration with robust action. Using chronic multichannel electrode arrays, we recorded neural activity from dorso-medial striatum in 4 rats performing the task and identified modulation response of each neuron to different events. Cell type classification was performed according to a multi-criteria clustering analysis. Results: Dorso-medial striatal neurons (n = 557) were recorded, of which 113 single units were considered as timing-relevant neurons, especially the fast-spiking subpopulation that had trial-to-trial ramping up or ramping down firing modulation during the time estimation period. Furthermore, these timing-relevant striatal neurons had to calibrate the spread of their firing pattern by rewarded experience to express the timing behavior accurately. Conclusion: Our data suggests that the dynamic activities of timing-relevant units encode information about the current duration and recent outcomes, which is needed to predict and drive the following action. These results reveal the potential mechanism of time calibration in a short temporal resolution, which may help to explain the neural basis of motor coordination affected by certain physiological or pathological conditions.

[Detection of lymph node micrometastasis for patients with extrahepatic cholangiocarcinoma and its prognostic significance].

OBJECTIVE: To observe the expression of antibodies of cytokeratin 19 and 20 in lymph node micrometastasis in patients with extrahepatic cholangiocarcinoma (EHCC), evaluate the prognostic significance of lymph node (LN) micrometastasis and study the correlation between lymph node micrometastasis and clinicopathological features, CA19-9 and CEA. METHODS: A total of 279 lymph nodes was intra-operatively collected from 59 EHCC patients and routine histological examination performed. Immunohistochemical staining was performed on all samples by the murine antibodies of anti-CK19 and anti-CK20 respectively. Then the micrometastasis was identified microscopically according to the color of cells. The results were analyzed according to clinical, pathological and follow-up data. And the relation of micrometastasis with clinical pathological factors and its impact upon survival rate were analyzed. RESULTS: Among 59 EHCC patients, 14 (23.72%) LN metastasis were found with HE staining and 21 micrometastases with CK staining. The incidence of nodal involvement in 59 EHCC patients increased from 5.37% (15/279) by HE staining to 13.98% (39/279) by CK staining. Among 45 patients not positive for LN metastases with HE staining, CK staining was positive in 7 patients and the incidence of micrometastasis was 15.56%. The preoperative serum CA19-9 levels in patients with LN micrometastasis was higher than that those without LN metastasis (P < 0.05). And there was a positive correlation between occult nodal micrometastasis and serum concentrations of CA19-9 (r(s) = 0.371, P < 0.05). The histological type and lymphatic vessel infiltration of tumor were the most importance factors for LN micrometastasis through Logistic regression analysis (P < 0.05). CONCLUSION: The CK immunohistochemical staining can detect the micrometastases in HE negative LN. And LN micrometastasis can more accurately predict the prognosis of EHCC patients.

[Study of intra-operative radiotherapy in primary liver cancer].

OBJECTIVE: To study the feasibility of intraoperative radiotherapy (IORT) in primary liver cancer. METHODS: Based on the target of dose curves, the dose-volume histogram (DVH) and cost of radiation equipment and radiation therapy, IORT was compared with protonbeam therapy (PBT) and 3DCRT in 16 patients with primary liver cancer using the therapy plan system (TPS). RESULTS: IORT had significantly better performance than 3DCRT to allow a target region surrounded by 90% of the dose lines. IORT was similar to protonbeam therapy in terms of target region surroundings and absorbed dose in the normal organs, but the cost of IORT was significantly lower. CONCLUSION: The TPS of IORT is better than 3DCRT and similar to protonbeam therapy in the treatment of primary liver cancer with similar cost to 3DCRT. IORT can effectively protect the neighboring sensitive organs and improve the absorbed dose in the tumors and the local control rate.

Long-range retrograde spread of LTP and LTD from optic tectum to retina.

Neural activity can induce persistent strengthening or weakening of synapses, known as long-term potentiation (LTP) or long-term depression (LTD), respectively. As potential cellular mechanisms underlying learning and memory, LTP and LTD are generally regarded as synapse-specific "imprints" of activity, although there is evidence in vitro that LTP/LTD may spread to adjacent synapses. Here, we report that LTP and LTD induced in vivo at retinotectal synapses of Xenopus tadpoles undergo rapid long-range retrograde spread from the optic tectum to the retina, resulting in potentiation and depression of bipolar cell synapses on the dendrites of retinal ganglion cells, respectively. The retrograde spread of LTP and LTD required retrograde signaling initiated by brain-derived neurotrophic factor and nitric oxide in the tectum, respectively. Such bidirectional adjustment of the strength of input synapses in accordance to that of output synapses may serve to coordinate developmental refinement and learning functions of neural circuits.

Serum from radiofrequency-injured livers induces differentiation of bone marrow stem cells into hepatocyte-like cells.

BACKGROUND: Roles that bone marrow stem cells (BMSCs) play in liver repair after liver injury and the cell therapy for liver diseases are widely accepted. However, the availability of hepatocyte-like cells from BMSCs and possible animal diseases association with culturing in fetal calf serum (FCS) are the major limitations of clinical therapy. Therefore, this study was designed to search for a new cell source for the treatment of liver injuries through investigating whether serum from radiofrequency ablation-injured rabbit livers can induce the differentiation of BMSCs into hepatocyte-like cells. METHODS: Serum was collected from rabbits 36 h after radiofrequency ablation (RFA) treatment of the liver. BMSCs were isolated from rabbit bone marrow and were cultured in the collected serum. Cellular morphology and cell cycle were observed. Hepatocyte markers of the differentiated cells were detected by immunohistochemistry. RESULTS: After induction for 7 d, spindle-shaped BMSCs turned into round cells that resembled the morphology of hepatocyte-like cells. Flow cytometry showed that the percentage of cells in the S/G2/M phase was higher in the RFA group than that in the FCS group and HGF groups. This result suggests that BMSC can transform into mature cells from stem cell phase. Albumin and CK18 were considered as typical marker of hepatocytes. Following induction for 14 d, the differentiated cells expressed immunofluorescence of FITC-labeled albumin and TRITC-labeled CK18. CONCLUSION: BMSCs treated with serum collected from radiofrequency ablation-injured livers can differentiate into hepatocyte-like cells providing a cell source to cell therapy.

[Expression of Survivin protein in extrahepatic cholangiocarcinoma and its relationship with the prognosis].

OBJECTIVES: To investigate the expression of Survivin in patients with extrahepatic cholangiocarcinoma (EHCC) and its relationship with clinicopathological features of EHCC, and the correlation between the expression of Survivin and lymph node micrometastasis, tumor markers, and the prognosis of EHCC. METHODS: The expression of Survivin protein in paraffin-embedded specimens of 59 patients with EHCC and their 20 para-carcinoma tissues were evaluated by S-P method of immunohistochemical staining. The correlation between the expression of Survivin and the lymph node micrometastasis, clinicopathological features of EHCC and the prognosis of EHCC were analyzed. RESULTS: The positive expression rate of Survivin protein was 67.8% (40/59) in paraffin-embedded specimens of 59 patients with EHCC and was 20.0% (4/20) in para-carcinoma tissues, and difference between carcinoma tissues and para-carcinoma tissues was significant (P<0.01). Histological differentiation in EHCC had a negative correlation with the expression of Survivin protein, while the expression of Survivin protein in EHCC had a positive correlation with TNM of EHCC, lymphatic vessel infiltration, lymph node metastasis and perineural invasion (P<0.05). The serum CA19-9 levels in the positive group with expression of Survivin protein was (290,300+/-55 500) U/L and was obviously higher than that in the negative group [(113,300+/-31,400) U/L, P<0.05]. The mean survival time of the patients with negative expression of Survivin protein was higher than that of the patients with positive expression (43.5 vs. 21.1 months, P<0.01). Screened to significance univariate, the multivariate analysis through Cox proportional hazard model analysis showed that lymph node metastasis, residual tumor margins, and expression of Survivin protein were independent prognosis factors of the patients with EHCC (P<0.05, P<0.01, P<0.01). CONCLUSIONS: The expression of Survivin protein in EHCC has a negative correlation with histological differentiation, while has a positive correlation with lymphatic vessel infiltration and serum CA19-9 concentrations. The expression of Survivin protein maybe an independent prognosis factor of the patients with EHCC.

[GC-box is not a key cis-acting element in human insulin gene promoter].

OBJECTIVE: To identify whether GC-box (-348 to -338) in human insulin gene promoter is a key cis-acting element. METHODS: Human insulin gene promoter was sub-cloned into secreted alkaline phosphatase (SEAP) reporter plasmid. The deletion and mutation of GC-box in insulin gene promoter was performed. The activity of human insulin gene promoter was determined by evaluating the activity of SEAP in the supernatant of cell culture after the reporter plasmids were transfected in beta cell line betaTC3. RESULT: Deletion and mutation of GC box in human insulin gene promoter did not result in significant changes of the activity of the promoter in betaTC3. CONCLUSION: The GC-box is not a key cis-acting element in human insulin gene promoter.

[Clinicopathological significance of homeobox BP1 mRNA expression in lung cancer tissue].

OBJECTIVE: To investigate the expression of beta-protein 1 (BP(1)) gene, a novel member of DLX homeobox gene family, in lung cancer tissue and its relationship with clinical features of lung cancer. METHODS: RT-PCR was employed for detecting BP(1) gene expression in the lung cancer tissues, adjacent tissues, non-cancer lung tissues of 46 lung cancer patients. RESULTS: Thirty-six lung cancer tissues and 6 adjacent tissues but none of the normal tissues were found to have BP(1) gene overexpression, showing significant difference in BP(1) expression between the tissues (P<0.01). Significant difference in BP1 gene overexpression was noted between well differentiated cancers (13 of out 21) and poorly differentiated cancers (22 of the 25), but not between cancers of different stages or between squamous carcinoma and adenocarcinoma. CONCLUSION: BP(1) gene expression is up-regulated in human lung cancer in related to the differentiation level of lung cancer but not to the clinical stage.

[Effect of prostaglandin E1 on monocyte chemotactic protein-1 expression in Kupffer cells of rats with hepatic ischemia-reperfusion injury].

OBJECTIVE: To observe the effect of prostaglandin E(1) (PGE(1)) on the expression of monocyte chemotactic protein-1 (MCP-1) in Kupffer cells (KCs) of rats with hepatic ischemia-reperfusion injury (IRI). METHODS: Seventy-two SD rats were randomized into sham operation group, ischemia-reperfusion group (I/R group) and PGE(1) treatment group (PGE(1) group). Rat models of partial warm ischemia-reperfusion injury of the liver was established, and in PGE(1) group, PGE(1) were given 10 min before the operation. At 1, 6, 12 and 24 h after the reperfusion, blood sample was taken from the inferior vena cava for measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. The KCs were isolated and incubated in vitro, and tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in the supernatant were measured by enzyme-linked immunosorbent assay. MCP-1 expression in the KCs was detected by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: ALT and AST levels of the PGE(1) group were significantly lower than I/R group (P<0.01). The mRNA and protein expression of MCP-1 and the TNF-alpha and IL-1beta levels in the I/R group significantly increased in the course of reperfusion and slightly decreased at 24 h, but were still significantly higher than those in the sham operation group (P<0.05). The expression of these factors were markedly decreased after PGE(1) treatment as compared with the I/R group (P<0.05). CONCLUSION: PGE(1) can protect against ischemia-reperfusion injury of the rat liver partially by suppressing KCs activation, reducing excessive release of TNF-alpha and IL-1beta from KCs and decreasing the high expression of MCP-1 protein and mRNA.

Clinical study on Ganbi decoction in treating antituberculotic agent-caused liver injury.

OBJECTIVE: To study the effect and mechanism of Ganbi decoction (GBD) in treating patients with antituberculotic agent caused liver injury (ATB-LI). METHODS: One hundred and twenty-eight patients with ATB-LI were randomly assigned to the treated group (n = 66) and the control group (n = 62) with the envelop method. Meanwhile, 60 healthy persons were selected as the healthy control group. The treated group was treated by GBD one dose every day with the constituents modified depending on patients' symptoms, and the control group was treated with glucuronolactone tablets and inosine injection. One week was taken as one treatment course. The changes of clinical syndromes, physical signs, T-lymphycyte sub-groups and serum level of nitric oxide (NO) were observed before and after treatment and the recovery time of liver function was recorded. The outcome was compared with that in the healthy control group. RESULTS: In the treated group, 28 patients (42.4%) were cured, 30 (45.5%) improved and 8 (12.1%) ineffectively cured, the total effective rate being 87.9% (58/66). In the control group, 17 patients (27.4%) were cured, 24 (38.7%) improved, and 21 (33.9%) ineffectively cured, the total effective rate being 66.1% (41/62). The total effective rate in the treated group was significantly higher than that in the control group (P < 0.05). Liver function was improved in both groups, recovery time in the treated group was 12.0 +/- 7.0 days, which was significantly shorter than that in the control group (16.0 +/- 8.0 days), showing significant difference between the two groups (P < 0.05). The levels of CD3, CD4 and CD8 were significantly higher and level of NO significantly lower in the two groups of patients than those in the healthy control group (P < 0.05), but these parameters were improved more significantly in the treated group after treatment, when compared with those before treatment or with those in the control group, all showing significant difference (P < 0.05). CONCLUSION: GBD could prevent ATB-LI, and its mechanism could be by way of reducing NO production induced by endotoxin of macrophage and stimulating the proliferation of T-lymphycyte to elevate immunity.

Expression of macrophage inflammatory protein-1alpha in Kupffer cells following liver ischemia or reperfusion injury in rats.

AIM: To explore the expression of macrophage inflammatory protein-1alpha (MIP-1alpha) in Kupffer cells (KCs) following liver ischemia/reperfusion injury IRI in rats. METHODS: Forty male SD rats were divided randomly into five groups. A model of partial warm ischemia/reperfusion injury in the rat liver was established. KCs were isolated and incubated one hour, six hours, 12 h, and 24 h after the reperfusion. Tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in the supernatants were measured by ELISA. MIP-1alpha in KCs was detected by immunocytochemical and RT-PCR. RESULTS: No or few MIP-1alpha protein and mRNA were expressed in the KCs of the control group. Its expression in the IRI group had a significant increase after the reperfusion (P < 0.05), which was contrary to the control group. CONCLUSION: The active behavior of the MIP-1alpha gene in KCs following liver ischemia/reperfusion injury is assumed to be one of the major causes for the hepatic ischemia/reperfusion injury.

Expression of angiostatin cDNA in human gallbladder carcinoma cell line GBC-SD and its effect on endothelial proliferation and growth.

AIM: To explore the influence of angiostatin up-regulation on the biologic behavior of gallbladder carcinoma cells in vitro and in vitro, and the potential value of angiostatin gene therapy for gallbladder carcinoma. METHODS: A eukaryotic expression vector of pcDNA3.1(+) containing murine angiostatin was constructed and identified by restriction endonuclease digestion and sequencing. The recombinant vector pcDNA3.1-angiostatin was transfected into human gallbladder carcinoma cell line GBC-SD with Lipofectamine 2000, and paralleled with the vector and mock control. The resistant clone was screened by G418 filtration. Angiostatin transcription and protein expression were examined by RT-PCR, immunofluorescence and Western-blot. The supernatant was collected to treat endothelial cells. Cell proliferation and growth in vitro were observed under microscope. RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). After 14 d of transfection and selection with G418, macroscopic resistant cell cloning was formed in the experimental group transfected with pcDNA 3.1(+)-angiostatin and vector control. But untreated cells died in the mock control. Angiostatin was detected by RT-PCR and protein expression was detected in the experimental group by immunofluorescence and Western-blot. Cell proliferation and growth in vitro in the three groups were observed respectively under microscope. No significant difference was observed in the growth speed of GBC-SD cells between groups that were transfected with and without angiostatin. After treatment with supernatant, significant differences were observed in endothelial cell (ECV-304) growth in vitro. The cell proliferation and growth were inhibited. CONCLUSION: Angiostatin does not directly inhibit human gallbladder carcinoma cell proliferation and growth in vitro, but the secretion of angiostatin inhabits endothelial cell proliferation and growth.

Association of cyclin D1, p16 and retinoblastoma protein expressions with prognosis and metastasis of gallbladder carcinoma.

AIM: To investigate the role of cyclin D1, p16 and retinoblastoma in cancerous process of gallbladder carcinomas and to assess the relation between cyclin D1, p16, Rb and the biological characteristics of gallbladder carcinoma. METHODS: Forty-one gallbladder carcinoma, 7 gallbladder adenoma and 14 chronic cholecystitis specimens were immunohistochemically and histopathologically investigated for the relation of cyclin D1, p16 and Rb with Nevin staging and pathologic grading. RESULTS: The expression rates of abnormal cyclin D1 in gallbladder carcinoma (68.3%) and gallbladder adenoma (57.1%) were significantly higher than those in chronic cholecystitis (7.1%) (P<0.05). No significant difference was found both among the pathological grades G(1), G(2) and G(3) and among Nevin stagings S(1)-S(2), S(3) and S(4)-S(5) of gallbladder carcinoma. The positive rates of p16 (48.8%) and Rb (58.5%) in gallbladder carcinoma were significantly lower compared to those in adenoma (100.0%) and cholecystitis (100.0%) (P<0.05). The positive rates of p16 and Rb in Nevin stagings S(1)-S(2) (80.0% and 90.0%) and S(3) (46.2% and 61.5%) gallbladder carcinomas were significantly higher than those in S(4)-S(5) (33.3% and 38.8%) (P<0.05), and those in pathologic grades G(1) (54.5% and 81.8%) and G(2) (50.0% and 62.5%) gallbladder carcinoma were significantly higher than those in G(3) (28.6% and 35.7%) (P<0.05). The protein expression of p16 and Rb had a negative-correlation in gallbladder carcinoma (r = -0.2993, P<0.05), and this negative-correlation was correlated with Nevin staging (P<0.05). Moreover, the protein expression of p16 and cyclin D1 had a negative-correlation in gallbladder carcinoma (r = -0.9417, P<0.05). CONCLUSION: Cyclin D1 may play a role in the early stage of gallbladder carcinoma. Mutation of p16 and Rb genes might be correlated with progression of gallbladder carcinoma. Analysis of p16 and Rb can estimate the prognosis of gallbladder carcinoma. Expression of p16 and Rb may be correlated with Nevin staging and pathologic grading in gallbladder carcinoma.

Relationship between inducible nitric oxide synthase expression and angiogenesis in primary gallbladder carcinoma tissue.

AIM: To explore the relationship between angiogenesis and biological behaviors of primary gallbladder carcinoma (PGBC), the relationship between the expression of inducible nitric oxide synthase (iNOS) and biological behaviors of PGBC and its relationship with the expression of iNOS and angiogenesis of PGBC. METHODS: The expression of iNOS and micro-vessel density (MVD) were assessed by immunohistochemical method and image analysis system in 40 specimens of PGBC and in 8 specimens of normal gallbladder. The immunostaining results and related clinicopathologic materials were analyzed by statistical methods. RESULTS: MVD in PGBC was significantly higher than that in normal gallbladder tissue (46+/-14 vs 14+/-6, P<0.05), and was not related with age, gender, tumor size and histological type. MVD of poorly and undifferentiated tumor tissues was higher than that of moderately-differentiated and well-differentiated tumor tissues (52+/-9 vs 43+/-9 vs 33+/-6, P<0.01). MVD of Nevin IV and V stages was higher than that of Nevin I, II and III stages (52+/-8 vs 37+/-13, P<0.01). MVD of cases with lymphatic or liver metastasis was significantly higher than that without liver metastasis (55+/-6 vs 42+/-10, P<0.05)or lymphatic metastasis (53+/-8 vs 38+/-8, P<0.01). The positive level index (PLI) of iNOS in PGBC was 0.435+/-0.134, and was not related with age, gender, tumor size, histological type, differentiation and clinical stage of PGBC. The PLI of iNOS in cases with lymphatic metastasis was higher than that without lymphatic metastasis (0.573+/-0.078 vs 0.367+/-0.064, P<0.01). The PLI of iNOS in cases with liver metastasis was higher than that without liver metastasis (0.533+/-0.067 vs 0.424+/-0.084, P<0.05). There was a significant correlation between PLI of iNOS and MVD in PGBC (P<0.05). CONCLUSION: Angiogenesis of PGBC is significantly related to the biological behaviors of PGBC. The expression of iNOS is related to the biological behaviors of PGBC. The detection of MVD and the expression of iNOS in PGBC can be used as parameters to determine the degree of malignancy and prognosis.

Effects of bile acids on proliferation and ultrastructural alteration of pancreatic cancer cell lines.

AIM: Pancreatic cancer in the head is frequently accompanied by jaundice and high bile acid level in serum. This study focused on the direct effects of bile acids on proliferation and ultrastructural alteration of pancreatic cancer. METHODS: Pancreatic cancer cell lines PANC-1, MIA PaCa-2 and PGHAM-1 were explored in this study. The cell lines were cultured in media supplemented with certain bile acids, CA, DCA, LCA, TCDC, TDCA and GCA. Their influence on cell growth was measured with MTT assay after 72 h of incubation. Cell cycles of PANC-1 cells in 40 microM of bile acids media were analyzed by flow cytometry. Ultrastructural alteration of PANC-1 cells induced by DCA was observed using scanning and transmission electron microscope (SEM and TEM). RESULTS: At various concentrations of bile acids and incubation time, no enhanced effects of bile acids on cell proliferation were observed. Significant inhibitory effects were obtained in almost all media with bile acids. DCA and CA increased the percentage of G0+G1 phase cells, while GCA and TDCA elevated the S phase cell number. After 48 h of incubation in DCA medium, PANC-1 cells showed some structural damages such as loss of their microvilli and vacuolization of organelles in cytoplasm. CONCLUSION: Bile acids can reduce proliferation of pancreatic cancer cells due to their direct cytotoxicity. This result implies that elevation of bile acids in jaundiced serum may inhibit pancreatic cancer progression.

Expression of proliferating cell nuclear antigen and CD44 variant exon 6 in primary tumors and corresponding lymph node metastases of colorectal carcinoma with Dukes' stage C or D.

AIM: To study changes in characteristics of colorectal carcinoma during the metastatic process and to investigate the correlation between cell proliferation activity and metastatic ability of patients with Dukes' stage C or D. METHODS: Formalin fixed and paraffin embedded materials of primary tumors and corresponding lymph node metastases resected from 56 patients with Dukes' stage C or D of colorectal carcinoma were stained immunohistochemically with proliferating cell nuclear antigen (PCNA) and CD44 variant exon 6 (CD44v6). RESULTS: Thirty-one of 56 patients (55.4 %) expressed PCNA in the primary sites and 36 of 56 patients (64.3 %) expressed PCNA in the metastatic lymph nodes. A significant relation in PCNA expression was observed between the primary site and the metastatic lymph node (0.010

Multivariate statistical analysis of clinicopathologic factors influencing survival of patients with bile duct carcinoma.

AIM: To evaluate the influence of various clinicopathologic factors on survival of patients with bile duct carcinoma after curative resection. METHODS: A retrospective analysis was made for 86 cases of bile duct carcinoma treated from January 1981 to September 1995. Fifteen clinicopathologic factors possibly influencing survival were selected. Independent variables were first analyzed by univariate methods. Survival for variable was estimated by the method of Kaplan and Meier. The variables that were statistically significant by univariate analysis were included in a multivariate analysis, which were confirmed using the Cox stepwise proportion hazard model with the help of SPSS 10.0 for Windows software. RESULTS: The overall cumulative survival rate was 72.6 % at 1 year, 32.4 % at 3 years, and 18.7 % at 5 years. The results of univariate analysis showed that the major significant prognostic factors influencing survival of these patients were histological type of lesion, lymph node metastasis, pancreatic invasion, duodenal invasion, perineural invasion, macroscopic vessel involvement, resected surgical margin and depth of cancer invasion (P=0.02, 0.02, 0.004, 0.005, 0.01, 0.43, 0.03 and 0.04). Age, sex, location of tumor, size of tumor, macroscopic type of lesions, hepatic metastasis, and hepatic invasion were not significantly associated with prognosis (P>0.05). Pancreatic invasion, perineural invasion and lymph node metastases were the three most important prognostic factors by multivariate analysis using the Cox proportional hazards model. CONCLUSION: Pancreatic invasion, perineural invasion and lymph node metastases are the most important prognostic factors for bile duct carcinoma after curative resection.