Application of Laennec extrathecal blockade combined with indocyanine green fluorescence imaging in laparoscopic anatomic hepatectomy

OBJECTIVE

To investigate the safety and application value of combining Laennec extracapsular occlusion with ICG fluorescence imaging in laparoscopic anatomic hepatectomy.

METHODS

Complete laparoscopic dissection was performed outside the Laennec sheath, blocking Glisson's pedicle of the corresponding liver segment or lobe. An appropriate amount of indocyanine green (ICG) dye was intravenously injected, and the boundary line between the pre-cut liver segment and liver lobe was identified using fluorescence laparoscopy. Complete resection of the liver segment or lobe was performed based on anatomical markers. Clinical data, including operation time, intraoperative blood loss, postoperative hospital stay, and postoperative complications, were collected.

RESULTS

A total of 14 cases were included in the study, including seven cases of primary liver cancer, three cases of metastatic liver cancer, three cases of intrahepatic bile duct calculi, and one case of hepatic hemangioma. All 14 patients underwent anatomic hepatectomy under fluorescent laparoscopy, with four cases involving the right liver, seven cases involving the left liver, two cases involving the right anterior lobe, and one case involving the right posterior lobe.

CONCLUSION

Combining laparoscopic follow-up of the Laennec membrane with Glisson outer sheath block and intraoperative ICG fluorescence imaging provides real-time guidance for locating the resection boundaries during anatomic hepatectomy. This approach helps in controlling intraoperative bleeding, reducing operation time, and ensuring high safety. It holds significant value in clinical application.

Correlation between gut microbiota and glucagon-like peptide-1 in patients with gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) places both the mother and offspring at high risk of complications. Increasing evidence suggests that the gut microbiota plays a role in the pathogenesis of GDM. However, it is still unclear whether the gut microbiota is related to blood biochemical traits, particularly glucagon-like peptide-1 (GLP-1), in GDM patients.

AIM

To explore the correlation between the gut microbiota and blood biochemical traits, particularly GLP-1, in GDM patients.

METHODS

The V4 region of the 16S ribosomal ribonucleic acid (rRNA) gene was sequenced based on the fecal samples of 35 pregnant women with GDM and was compared to that of 25 pregnant women with normal glucose tolerance (NGT).

RESULTS

The results showed that Ruminococcaceae_UCG-002, Ruminococcaceae_UCG-005, Clostri-dium_sensu_stricto_1, and Streptococcus were more abundant in the NGT group than in the GDM group. Bacteroides and Lachnoclostridium were more abundant in the GDM group than in the NGT group. Spearman’s correlation analysis was performed to identify the relationships between microbiota genera and blood biochemical traits. Paraprevotella, Roseburia, Faecalibacterium, and Ruminococcaceae_UCG-002 were significantly negatively correlated with glucose. Ruminococcaceae_UCG-002 was significantly negatively correlated with hemoglobin A1c. Bacteroides was significantly positively correlated with glucose. Sutterella, Oscillibacter, and Bifidobacterium were significantly positively correlated with GLP-1. A random forest model showed that 20 specific genera plus glucose provided the best discriminatory power, as indicated by the area under the receiver operating characteristic curve (0.94).

CONCLUSION

The results of this study reveal novel relationships between the gut microbiome, blood bio-chemical traits, particularly GLP-1, and GDM status. These findings suggest that some genera are crucial for controlling blood glucose-related indices and may be beneficial for GDM treatment. Alteration in the microbial composition of the gut may potentially serve as a marker for identifying individuals at risk of GDM.

LncRNA SNHG14 potentiates pancreatic cancer progression via modulation of annexin A2 expression by acting as a competing endogenous RNA for miR-613

This study aimed to determine long non-coding RNA (lncRNA) small nucleolar RNA host gene 14 (SNHG14) expression in pancreatic cancer and to explore the potential molecular actions of SNHG14 in mediating pancreatic cancer progression. Gene expression was detected by quantitative real-time PCR. Cell proliferation, growth and invasion were detected by respective CCK-8, colony formation, and transwell invasion assays. Protein levels were measured by Western blotting. Cell apoptosis and caspase-3 activity were detected by flow cytometry and caspase-3 activity assay. The link between miR-613 and its targets was evaluated by luciferase reporter assay. In vivo tumour growth was evaluated using a xenograft model of nude mice. SNHG14 expression was up-regulated in cancerous tissues from pancreatic cancer patients. High expression of SNHG14 was associated with poor tumour differentiation, advanced TNM stage and nodal metastasis. SNHG14 overexpression enhanced cell proliferative, growth and invasive abilities, and suppressed apoptotic rates and caspase-3 activity in pancreatic cancer cells, while SNHG14 knockdown exerted opposite effects. Mechanistic studies revealed that miR-613 was targeted by SNHG14, and Annexin A2 (ANXA2) was targeted and inversely regulated by miR-613 in pancreatic cancer cells. In vivo studies showed that SNHG14 knockdown attenuated tumour growth. MiR-613 was down-regulated and ANXA2 was up-regulated in the pancreatic cancer tissues, and SNHG14 expression levels were inversely correlated with miR-613 expression levels and positively correlated with the ANXA2 mRNA expression levels. Collectively, our results suggest that SNHG14 potentiates pancreatic cancer progression through modulation of annexin A2 expression via acting as a competing endogenous RNA for miR-613.

[Preoperative C-reactive protein/albumin ratio predicts the prognosis of patients with resectable pancreatic cancer]

Objective: To evaluate the clinical significance of C-reactive protein/albumin ratio in predicting the postoperative prognosis of pancreatic cancer patients. Methods: The clinical date of 97 patients with resectable pancreatic cancers who treated at Department of Hepatobiliary and Pancreatic Surgery, the third Affiliated Hospital of Soochow University from January 2005 to December 2015 were analyzed retrospectively. The cut-off value of CRP/Alb ratio was determined by the receiver operating characteristic(ROC) curve. According to the CRP/Alb ratio, patients were respectively divided into two groups: the high group(CRP/Alb ratio≥0.109) and the low group(CRP/Alb<0.109). The relationships between CRP/Alb ratio and clinical characteristics were analyzed by χ(2) test. Median survival and 1-year overall survival rate(OS) was calculated by Kaplan-Meier method.The risk factors of patients with poor prognosis were analyzed by univariate and multivariate Cox regression analysis model. Results: Tumor TNM stage(χ(2)=4.280, P=0.039) and differentiation(χ(2)=6.635, P=0.010) had significant relationship with CRP/Alb ratio. The median survival of higher CRP/Alb ratio group and lower CRP/Alb ratio group was 15 months and 23 months respectively. Compared with lower CRP/Alb ratio group, the 1-year OS of higher CRP/Alb ratio group decreased remarkablely, and the difference was statistically(χ(2)=10.207, P=0.001). Moreover, median survival and OS were decreased in patients with advanced age(≥65 years old: χ(2) =5.338, P=0.021), high TNM stage(ⅡB-Ⅲ: χ(2) =10.529, P=0.001), poor tumor differentiation(χ(2)=5.380, P=0.020), vascular invasion(χ(2) =7.856, P=0.005) and positive surgical margin(χ(2)=9.059, P=0.003). A high CRP/Alb ratio was identified as an independent risk factor of poor prognosis for patients with pancreatic cancer(HR=1.832, 95% CI: 1.067-3.144, P=0.028). Besides, old age(HR=1.684, P=0.014), high TNM stage(HR=1.666, P=0.031), vascular invasion(HR=1.834, P=0.024) and positive surgical margin(HR=2.205, P=0.023) were also included. Conclusion: Preoperative CRP/Alb ratio can be an important clinical factor for assessing the prognosis of patients with resectable pancreatic cancers, and high CRP/Alb ratio suggests poor prognosis.

[Relevant molecular characteristics analysis on malignant transformation of interstitial cells induced by tumor stem cells in glioma microenvironment]

Objective: A variety of interstitial cells in tumor microenvironment (TME) based on glioma stem cells(GSC) have the function to promote malignant progression of tumors, but whether these interstitial cells have already undergone malignant transformation and their related molecular characteristics are still poorly understood. Methods: Human SU3-RFP glioma stem cells (GSC) stably transfected with red fluorescent protein (RFP) and interstitial cells from enhanced green fluorescent protein (EGFP) transgenic nude mice were co-cultured in vitro. SU3-RFP cells were also inoculated in different tissues of EGFP-Balb/c nude mice. Immortal EGFP(+) cells were monocloned either from co-culture cells in vitro, or from their xenografts in vivo. These immortal EGFP(+) cells were confirmed to bear characteristics of tumor cell via chromosomal analysis and tumorigenicity assay. Related molecular phenotypes of these cells were further detected through RT-PCR, flow cytometry and immunochemistry(IHC) techniques. Results: (1) Two EGFP(+) cell lines were obtained in vitro, and 5 EGFP(+) cell lines were obtained in vivo tumorigenic experiments. Seven EGFP(+) cell lines all have characteristics of self-renewal, heteroploid of chromosomes and 100% tumorigenicity. (2) Cell surface marker analysis showed cell origin of these cell lines were macrophages (tMΦ1 and tMΦ2 ), dendritic cells (tDC1 and tDC2), fibroblasts (tFB), oligodendrocytes (tOG) and BMSC cells (tBMSC), respectively. (3)All of these seven cell lines co-expressed Sca-1 and c-myc, and have Sox-2 or Nanog expression also, which suggest that they may bear molecular characteristics of mesenchymal stem cells or pluripotent stem cells. Conclusions: (1) Tumor stromal cells in TME have undergone malignant transformation, which is related to the tissue remodeling of TME by GSCs, and not limit to the specific type of their parasitic tissues. (2) Tumor cells originated from GSC and tumor interstitial cells, respectively, are two major types of tumor cells with different origins in glioma parenchyma, can not be simply regarded as tumor heterogeneity, transformed interstitial cells of TME may have the potential to serve as new targets for target diagnosis and therapy.

LncRNA DLX6-AS1 promoted cancer cell proliferation and invasion by attenuating the endogenous function of miR-181b in pancreatic cancer

Background

Pancreatic cancer, one of the most aggressive malignancies, ranks the fourth cause of cancer-related death worldwide. Aberrantly expressed long non-coding RNAs (lncRNAs) functioned as oncogenes or tumor suppressors in pancreatic cancer. This study aimed to determine the expression of lncRNA DLX6 antisense RNA 1 (DLX6-AS1) in pancreatic cancer tissues and to explore the DLX6-AS1-related pathway in pancreatic cancer.

Materials and methods

The gene expression levels were determined by quantitative real-time PCR, and protein expression levels were determined by western blot assay. CCK-8 assay, colony formation assay and Transwell migration and invasion assays were used to examine cell proliferation, migration and invasion. Luciferase reporter assay was used to confirm the binding between DLX6-AS1and its potential targets. In vivo study used the mouse xenograft model to test the anti-tumor effect of DLX6-AS1 knockdown.

Results

The high expression of DLX6-AS1 was observed in pancreatic cancer tissues, and high expression of DLX6-AS1 was positively correlated with larger tumor size, advanced TNM stage and lymph node metastasis. Knockdown of DLX6-AS1 dramatically impaired cancer cell proliferation, migration and invasion. MiR-181b was the downstream target of DLX6-AS1. Knockdown of miR-181b reversed the suppression of cell viability, migration and invasion abilities caused by DLX6-AS1 knockdown. MiR-181b was found to target Zinc finger E-box-binding homeobox 2 and to modulate epithelial-mesenchymal transition. Furthermore, DLX6-AS1 knockdown inhibited tumor growth and tumor metastasis in vivo.

Conclusion

Collectively, our data suggested that DLX6-AS1 promotes cancer cell proliferation and invasion by attenuating the endogenous function of miR-181b in pancreatic cancer.

[Down-regulation of miR-146b-5p promotes malignant transformation of fusion cells after co-culture of macrophages with glioma stem cells in vitro]

Objective: To observe mutual interactions between macrophages(Mφ) and glioma stem cells (GSCs)in dual-color tracing model in vitro, to identify the biological characteristics of fusion cells in multiple levels, and to analysis the relevant molecular mechanisms. Methods: Red fluorescent protein(RFP) gene was stably transfected into human GSCs cell line SU4. Mφ cells were obtained from Balb/c nude mice with enhanced green fluorescent protein (EGFP) expression. Then two cells were co-cultured in dual-color tracing platform. RFP/EGFP double positive cells with high proliferation ability were mono-cloned. The fusion cells were verified by Western blot, fluorescence in situ hybridization, immunocytochemistry and chromosome karyotype analysis.The biological characteristics of fusion cells were further analyzed, together with relevant molecular changes. Results: RFP / EGFP double positive cells were obtained through in vitro co-culture. RFP and EGFP coexpression were proved at transcriptional and translational levels in the fusion cells. They also co-expressed GSCs marker Nestin and Mφ marker CD68, and karyotype analysis showed two types of characteristic chromosomes, which confirmed that the fusion cells originated from spontaneous fusion between SU4-RFP and Mφ.Fusion cell proliferation rate and invasion ability were higher than SU4-RFP, which were relevant with down-regulation of miR-146b-5p and activation of STAT3. Fusion cells transfected with miR-146b-5p showed a higher apoptosis rate(18.83%) and lower tumor formation(4/5). Conclusion: Mφ could fuse with GSCs spontaneously in local tumor micro-environment. The proliferation and invasion abilities of fusion cells were higher than their parent cells, which were relevant with down-regulation of miR-146b-5p and activation of STAT3. It revealed the possible mechanisms of malignant progression of gliomas.

Laparoscopic Partial Splenectomy: A Preferred Method for Select Patients

BACKGROUND

The purpose of this study was to explore the feasibility and safety of laparoscopic partial splenectomy (LPS) using a harmonic scalpel (HS) combined with bipolar coagulation.

MATERIALS AND METHODS

Using HS and bipolar coagulation technology, 18 patients suffering from splenic cystic neoplasm were treated with LPS between January 2010 and December 2014, and their clinical data were analyzed retrospectively.

RESULTS

LPS was performed successfully without conversion to open surgery in all cases. The mean intra-operative blood loss was 75.8 ± 33.5 mL, and the mean operation time was 54.3 ± 16.6 minutes (range, 48-82 minutes). No cases of postoperative bleeding, infection, or pancreatic fistula occurred. No patient required total splenectomy. The mean hospital stay was 6.6 ± 3.2 days, and the median postoperative follow-up was 19.8 months (range, 5-60 months). All patients recovered successfully, with normal complete blood counts and without any recurrence on follow-up.

CONCLUSIONS

LPS is a safe and feasible operation for selected patients. Combined use of an HS and bipolar coagulation can shorten the operation time, reduce blood loss, and improve the safety of the operation.

Treatment of Early Stage Endometrial Cancer by Transumbilical Laparoendoscopic Single-Site Surgery Versus Traditional Laparoscopic Surgery: A Comparison Study

To compare the outcomes of transumbilical laparoendoscopic single-site surgery (TU-LESS) versus traditional laparoscopic surgery (TLS) for early stage endometrial cancer (EC).We retrospectively reviewed the medical records of patients with early stage EC who were surgically treated by TU-LESS or TLS between 2011 and 2014 in a tertiary care teaching hospital. We identified 18 EC patients who underwent TU-LESS. Propensity score matching was used to match this group with 18 EC patients who underwent TLS.All patients underwent laparoscopic-assisted vaginal hysterectomy, bilateral salpingo-oophorectomy, and systematic pelvic lymphadenectomy by TU-LESS or TLS without conversion to laparoscopy or laparotomy. Number of pelvic lymph nodes retrieved, operative time and estimated blood loss were comparable between 2 groups. Satisfaction values of the cosmetic outcome evaluated by the patient at day 30 after surgery were significantly higher in TU-LESS group than that in TLS group (9.6 ± 0.8 vs 7.5 ± 0.7, P < 0.001), while there was no statistical difference in postoperative complications within 30 days after surgery, postoperative hospital stay, and hospital cost.For the surgical management of early stage EC, TU-LESS may be a feasible alternative approach to TLS, with comparable short-term surgical outcomes and superior cosmetic outcome. Future large-scale prospective studies are needed to identify these benefits.

HtrA1 regulates epithelial-mesenchymal transition in hepatocellular carcinoma

BACKGROUND AND AIMS

Epithelial-mesenchymal transition (EMT) is involved in the development and progression of cancer. HtrA1 had been showed to play a modulatory role in metastasis of hepatocellular carcinoma (HCC). The relationship between HtrA1 and EMT in HCC was investigated in the present study.

METHODS

The HtrA1 expression in human HCC tumor tissues and cells was determined by real-time PCR. SiRNA-HtrA1 and pcDNA-HtrA1 were respectively transfected into HepG2 and MHCC97H cells to observe their effects on cell migration and expression of EMT-associated markers Vimentin and E-cadherin. The relationship between HtrA1 and EMT in 60 HCC patients was also investigated.

RESULTS

HtrA1 expression of tumor tissues was down-regulated with the increasing of number in lymph nodes metastasis in HCC patients. HtrA1 down-regulation led to the significant increase of cell migration, Vimentin expression and decrease of E-cadherin expression, while HtrA1 overexpression resulted in an opposite function. The HtrA1 expression was positively related to the E-cadherin level (R(2) = 0.5903, P < 0.001) and negatively correlated with Vimentin level (R(2) = 0.6067, P < 0.001) in tumor tissues of HCC, respectively.

CONCLUSION

HtrA1 expression was closely related to EMT, which might be a potential mechanism underlying metastasis of HCC.

Resveratrol could reverse the expression of SIRT1 and MMP-1 in vitro

Intervertebral disc degeneration is the main cause of lumbago disease, in which the extracellular matrix structure and moisture in the nucleus pulposus is lost continuously. In this study, we aimed to detect differential expression of silence mating type information regulation 2 homolog 1 (SIRT1) and matrix metalloproteinase-1 (MMP-1) in human intervertebral disc nucleus pulposus cells and to explore the effects of SIRT1 and MMP-1 on the development of the intervertebral disc degeneration. Intervertebral disc nucleus pulposus specimens from 41 patients who underwent lumbar protrusion resection at HuiZhou Municipal Central Hospital, during the period from October 2011 to December 2013, were studied in comparison with 23 control cases from patients who underwent fractured lumbar resection. In degenerated human intervertebral disc nucleus pulposus cells, the expression of SIRT1 is decreased and MMP-1 is increased compared with that of the control cells. Resveratrol could reverse these effects, thereby increasing the expression of SIRT1 (0.87 ± 0.07 vs 0.54 ± 0.04), Coll2α1 (0.90 ± 0.08 vs 0.38 ± 0.01), and aggrecan (0.69 ± 0.07 vs 0.42 ± 0.05) and decreasing the expression of MMP-1 (0.61 ± 0.03 vs 0.93 ± 0.08). These results suggest that resveratrol could possibly reverse the process of intervertebral disc degeneration and thus could be applied as a potential drug for the disease.

Transcystic approach with micro-incision of the cystic duct and its confluence part in laparoscopic common bile duct exploration

BACKGROUND

Laparoscopic transcystic common bile duct exploration has become a safe and ideal treatment of common bile duct stones. This study was designed to explore the clinical value of modified laparoscopic transcystic common bile duct exploration as a first line of treatment for patients with common bile duct stones.

PATIENTS AND METHODS

A retrospective, case-control study of clinically comparable groups of patients who underwent the laparoscopic transcystic approach with micro-incision of the cystic duct and its confluence part in common bile duct exploration (LTM-CBD) (n=110) and laparoscopic common bile duct exploration (LCBD) (n=100) under the care of one surgeon was performed. All clinical data were analyzed retrospectively.

RESULTS

There was no significant difference in terms of operation time between the two groups (P>.05). Postoperative hospital stay and abdominal drainage time were shorter in the LTM-CBD group than in the LCBD group (P<.05). Postoperative bile leakage was seen in 1 case (1 of 110) in the LTM-CBD group and 10 cases (10 of 100) in the LCBD group (P<.05). Twenty patients underwent T-tube drainage in the LCBD group, and primary closure was performed in the other patients; however, all cases in the LTM-CBD group underwent primary closure. The median follow-up was 12 months; 2 patients in the LCBD group who suffered from bile leakage presented with obstructive jaundice due to bile duct stenosis 6 months postoperatively.

CONCLUSIONS

LTM-CBD, which can avoid postoperative T-tube drainage, decrease complications, shorten hospitalization time, and enhance the existing quality, is a minimally invasive, safe, and effective treatment.

Clinical efficacy and safety of selective trans-cystic intra-operative cholangiography in primary suture following three-port laparoscopic common bile duct exploration

BACKGROUND

Intra-operative cholangiography has been shown to be a sensitive and specific method of demonstrating bile duct stones. This study investigated the feasibility, safety, and clinical value of selective trans-cystic intra-operative cholangiography in primary suture following three-port laparoscopic common bile duct exploration, and identified the factors that positively predict the presence of common bile duct stones.

METHODS

From January 2008 to January 2011, 252 of 1013 patients undergoing laparoscopic cholecystectomy received selective trans-cystic intra-operative cholangiography and primary suture following three-port laparoscopic common bile duct exploration. Their clinical data were analyzed retrospectively.

RESULTS

All operations were successful and none was converted to open surgery. The intra-operative cholangiography time was (8.3 ± 2.5) minutes, and the operative duration was (105.4 ± 23.1) minutes. According to selective intra-operative cholangiography, the positive predictive values of current jaundice, small gallstones (< 0.5 cm) and dilated cystic duct (> 0.3 cm), dilated common bile duct (> 0.8 cm), history of jaundice or gallstone pancreatitis, abnormal liver function test, and preoperative demonstration of suspected common bile duct stones on imaging were 87%, 25%, 42%, 15%, 32%, and 75% for common bile duct stones, respectively. Patients with several factors suggestive of common bile duct stones yielded higher numbers of positive cholangiograms. Unexpected stones were found in 13 patients (5.2%) by intra-operative cholangiography. The post-operative hospital stay was (4.7 ± 2.2) days. Post-operative bile leakage occurred in two cases, and these patients recovered by simple drainage for 3 - 7 days without re-operation. Of the 761 patients who underwent laparoscopic cholecystectomy alone, 5 (0.7%) presented with a retained common bile duct stone requiring intervention. The median follow-up was 12 months, and only one patient who once suffered from bile leakage presented with obstructive jaundice due to bile duct stenosis 6 months postoperatively. The other patients recovered without any serious complications.

CONCLUSIONS

Selective intra-operative cholangiography yields acceptably high positive results. It is a safe, effective, and minimally invasive approach in patients with suspected choledocholithiasis and primary suture following three-port laparoscopic common bile duct exploration.

Aberrant methylation frequency of TNFRSF10C promoter in pancreatic cancer cell lines

BACKGROUND

A growing body of evidence suggests that many tumors are initiated by both epigenetic abnormalities and gene mutations, which promote tumor progression. Epigenetic abnormalities include changes in DNA methylation and in the modification of histones. This study aimed to assess the status of methylation in the CpG island (CGI) of the tumor necrosis factor receptor superfamily member 10c (TNFRSF10C) with combined bisulfite restriction analysis (COBRA) and to evaluate its role in the progression of pancreatic cancer (PC).

METHODS

The methylation status of four PC cell lines was assessed using COBRA and/or bisulfite genomic sequencing (BGS). Changes in methylation and TNFRSF10C expression in PC cell lines before and after treatment with 5-aza-2'-deoxycytidine (5-aza-dC) and/or trichostatin A (TSA) were assessed by BGS and real-time RT-PCR. Apoptosis in the four cell lines was tested by flow cytometry (FCM) and TUNEL assay.

RESULTS

The methylation status of the TNFRSF10C promoter was assessed in PC cells (BxPC-3: 68.84+/-8.71%; CFPAC-1: 0; PANC-1: 96.77+/-4.57%; SW1990: 54.97+/-7.33%) with the COBRA assay, which was confirmed by the results of BGS. After treatment with 5-aza-dC and/or TSA, apoptosis was induced in PC cells to different degrees, and the levels of TNFRSF10C transcriptional expression in the PC cell lines (except CFPAC-1) increased markedly after 5-aza-dC treatment.

CONCLUSIONS

A high frequency of CGI methylation in the TNFRSF10C promoter results in inactivation of the gene and enhancement of tumor growth in most PC cell lines (except CFPAC-1). Inactivation of TNFRSF10C by CGI hypermethylation can play an important role in PC progression and be potentially useful as a diagnostic marker and a new therapeutic approach for PC.

Side population in the pancreatic cancer cell lines SW1990 and CFPAC-1 is enriched with cancer stem-like cells

In this study, we first sought to determine the existence of side population (SP) cells in pancreatic cancer cell lines. Furthermore, we compared the biological characteristics of SP and non-SP cells. The presence of side population cells in pancreatic cancer cell lines was detected by Hoechst 33342 staining and FACS analysis. Cell cycle distribution was analyzed using flow cytometry. SP and non-SP cells were exposed to various concentrations of gemcitabine; drug sensitivity was examined using the MTT assay and flow cytometry using Annexin-V and PI staining. To compare the tumorigenic ability in vivo, groups of nude mice were orthotopically inoculated with varying numbers of SP and non-SP cells. The percentages of CD44+CD24+ and CD133+ in SP and non-SP cells were also detected by FACS analysis. The SP fraction was detected in BxPc-3, CFPAC-1, MIA PaCa-2, PANC-1 and SW1990 pancreatic cancer cell lines. Cell cycle analysis revealed that the SP cells contained more cells in the G1 phase and fewer cells in the S phase when compared with the non-SP cells. The SP cells exhibited increased tumorigenetic ability following in vivo transplantation into BALB/C nude mice and increased chemoresistance following in vitro exposure to gemcitabine. FACS analysis showed that the SP cells contained more CD44+CD24+ and CD133+ cells than the non-SP cells. In conclusion, these observations suggest that SP cells in the pancreatic cancer cell lines possess the property of cancer stem cells. SP cells may therefore be novel specific targets for the effective treatment of pancreatic cancer.

[Establish a gemcitabine-resistant pancreatic cancer cell line SW1990/GZ and research the relationship between SW1990/GZ and pancreatic cancer stem cell]

OBJECTIVES

To establish a gemcitabine-resistant pancreatic cancer cell line SW1990/GZ, and to explore the relationship between drug-resistant cell line SW1990/GZ and pancreatic cancer stem cell.

METHODS

Gemcitabine-resistant pancreatic cancer cell line SW1990/GZ was obtained by treating parental cell line SW1990 in vitro with increasing dosage of gemcitabine in culture medium intermittently for 24 weeks. Stable cultures were obtained which were 77.2-fold increased in resistance relative to parental cells. Gene expressions of ABCB1/MDR1, ABCC1/MRP and ABCG2/BCRP were determined by real-time PCR. Tumorigenic potential was performed by nude mice xenograft transplant experiments. Side population analysis and CD24CD44 positive cells explore were determined by flow cytometry to examine cancer stem cell proportion.

RESULTS

Gemcitabine-resistant cell line SW1990/GZ underwent obvious morphological and functional changes. Compared with the parental cell line, SW1990/GZ cell was small and turned into round shape. SW1990/GZ had a higher gene expression level of ABCB1/MDR1, ABCC1/MRP and ABCG2/BCRP than SW1990 (P < 0.01). Nude mice xenograft transplant experiments showed that only 1 × 10(5) SW1990/GZ cells were sufficient for tumor formation, whereas an injection of 1 × 10(5) SW1990 cells did not initiate tumors. Flow cytometry analysis showed that SP proportion in SW1990/GZ was (11.0 ± 1.0)%, whereas in parental SW1990 it was (4.6 ± 0.9)%, CD44CD24 positive cells was (8.73 ± 0.81)% in SW1990/GZ, whereas (1.1 ± 0.4)% in SW1990.

CONCLUSIONS

Gemcitabine-resistant cell line SW1990/GZ has a higher proportion of pancreatic cancer stem cells compared to its parental cell line SW1990. CD44 is mainly responsible for acquired drug resistance, which can be a potential target to overcome acquired drug resistance in pancreatic cancer.

Effect of human recombinant growth hormone on proliferation of pancreatic carcinoma cell line BXPC-3 and its possible mechanism

AIM: To explore the in vitro effect of human growth hormone (GH) on the proliferation of pancreatic carcinoma cell line (BXPC-3 cells) as well as the possible mechanism.

METHODS: BXPC-3 cells during exponential growth stage were harvested and divided into experimental group and control group. The experimental group was separated into four sub-groups according to the doses of GH (50, 100 μg/L) and culture time (2, 24 h). Insulin-like growth factors 1, 2 (IGF-1, IGF-2) were detected by enzyme-linked immunosorbent assay (ELISA). BXPC-3 cells cultured for 24 h with various GH concentrations were made into single cell suspensions and the samples underwent subsequent cell cycle evaluation. IGF-1 receptor mRNA and IGF-2 receptor mRNA were tested with in situ hybridization.

RESULTS: The GH-stimulated cell growth in vitro and the cell proliferation index (PI) were significantly increased after 24-h culture (cell number: 8.44 ± 1.25, 7.50 ± 0.64 vs 5.26 ± 0.65, P < 0.05; PI: 0.60 ± 0.06, 0.57 ± 0.04 vs 0.50 ± 0.04, P < 0.05), while the number of S-phase cells was also markedly increased (47.62% ± 6.74%, 54.60% ± 7.59% vs 38.37% ± 4.99%, P < 0.05). The quantity of IGF-1 was significantly increased after 2-h culture in the experimental group, but there was no statistical significance between the two groups after 24-h culture. The IGF-1 receptor mRNA and the IGF-2 receptor mRNA were positively expressed in BXPC-3 cells. Furthermore, the expression of IGF-1 receptor mRNA was increased after GH induction, but the expression of IGF-2 receptor mRNA was not.

CONCLUSION: GH can stimulate the proliferation of pancreatic carcinoma cells in vitro and the possible mechanism may be related to the axis of GH-IGF-1.

Relationship between the GH-IGFs axis and the proliferation of bile duct cancer cell line QBC939 in vitro

BACKGROUND

In recent years, recombined human growth hormone (rhGH) has been increasingly used in patients to help them recover from operation. But GH, as a mitogen, can promote cell renewal and increase malignant transformation. In the current study, we assessed the proliferation of a bile duct cancer cell line (QBC939) in vitro with GH and explored the possible relationship with the axis of GH-IGFs (insulin-like growth factors).

METHODS

QBC939 cells in the exponential growth stage were harvested and divided into an experimental group (GH group) and a control group (NS group). The GH group was divided into four sub-groups according to the dose of GH and culture time (50 microg/L for 2 hours, 50 microg/L for 24 hours, 100 microg/L for 2 hours, 100 microg/L for 24 hours). The NS group was divided into two sub-groups (NS for 2 hours and NS for 24 hours). After 2 or 24 hours, IGF-1 and IGF-2 were detected using the enzyme-linked immunosorbent assay. The QBC939 cells cultured for 24 hours with two GH concentrations were made into single cell suspensions and samples underwent subsequent cell cycle evaluation. Messenger RNA of IGF-1 and IGF-2 receptor (IGF-1RmRNA and IGF-2RmRNA) were tested with the method of in situ hybridization.

RESULTS

There was no statistically significant difference between the GH and NS groups after 2 hours of culture (P>0.05). But after 24 hours of culture, GH stimulated cell growth in vitro and also elevated the percentage in S phase and the proliferation index (P<0.05). IGF-1RmRNA and IGF-2RmRNA were expressed in QBC939 in contrast to the blank group. The expression of IGF-1RmRNA increased with the dose of GH, but IGF-2RmRNA did not.

CONCLUSION

GH can stimulate QBC939 cell growth and proliferation in vitro and the mechanism is most likely by the GH-IGF-1-IGF-1R axis.