Objective To investigate the changes in the tumor microenvironment of pancreatic cancer(PDAC)complicated with diabetes mellitus(DM)in a mouse model of hyperglycemia and orthotopic pancreatic cancer by analyzing transcriptome and single-cell transcriptome data in order to identify potential therapeutic targets.Method By integrating single-cell transcriptome and bulk transcriptome data,bioinformatics analysis was conducted to compare the characteristics of tumor cells and tumor immune microenvironment between PDAC patients with DM(DM group)and those without DM(non-DM group).Twenty male C57BL/6 mice(6 weeks old,weighing 18～20 g)were randomly divided into a hyperglycemic group[STZ group,continuous intraperitoneal injection of 50 mg/kg streptozocin(STZ)(final concentration of 1％)dissolved in citrate buffer],and a control group(Control group,an equivalent volume of citrate buffer without STZ at the same time points),with 10 mice in each group.Tail-tip blood glucose level was measured to monitor glycemic status.After orthotopic inoculation of pancreatic cancer cells in both Control and STZ groups,tumor-infiltrating immune cells were harvested.Flow cytometry was employed to determine the effects of hyperglycemia on:total CD8+T cell and Treg cell populations;CD8+T cell subsets expressing Ki67,TNF-α,granzyme B(GZMB)and IFN-γ;surface expression of PD-1,lymphocyte activation gene-3(LAG-3)and T cell immunoglobulin and mucin domain-3(Tim-3)on CD8+T cells;programmed death-ligand 1(PD-L1)expression on tumor cells;and tumor-associated macrophage surface expression of major histocompatibility complex classⅠ(MHC-Ⅰ)and cluster of differentiation 206(CD206).Results Bioinformatics analysis revealed that,compared to the non-DM group,the genes significantly up-regulated in the DM group were associated with poor prognosis(P＜0.001).The proportion of type 2 ductal cells was increased in the DM group,exhibiting higher levels of copy number variation(P＜0.001).In the tumor immune microenvironment of the DM group,there was an increase in the proportion of Treg cells(P＜0.05)and an elevated exhaustion score for CD8+T cells(P＜0.001),accompanied by down-regulated expression of effector molecules,up-regulated expression of inhibitory checkpoints,and a significant increase in the M2 score of M2-like macrophages(P＜0.001).Animal experiments and flow cytometry found that,compared to the Control group,the STZ group had a shorter survival time(P＜0.001),with decreased proportions of total CD8+T cells(P＜0.01)and CD8+T cells expressing Ki67,TNF-α,GZMB and IFN-γ(P＜0.01),increased proportion of Treg cells(P＜0.001),up-regulated expression of PD-1,LAG-3 and Tim-3 on the surface of CD8+T cells(P＜0.001),and up-regulation of PD-L1 on tumor cell surface(P＜0.001)and enhanced expression of CD206 on the surface of tumor-associated macrophages,while down-regulated expression of MHC-Ⅰ(P＜0.001).Conclusion High glucose promotes the formation of an immunosuppressive microenvironment in PDAC,and targeting type 2 ductal cells and immunosuppressive cells in the tumor microenvironment,combined with dual immune checkpoint antibody therapy,may improve patient prognosis.

Objective To explore the role of mitophagy in pancreatic cancer cachexia-induced muscle atrophy and its underlying mechanism.Methods Six male C57BL/6J mice(8 weeks old,weighing 20～30 g)were equally and randomly divided into a control group(intrapancreatic injection of normal saline)and a cachexia group(orthotopic pancreatic injection of KPC1199 cells).After successful model establishment,gastrocnemius muscles were harvested for transmission electron microscopy(TEM)to assess mitochondrial ultrastructure.Western blotting was performed to quantify mitochondrial respiratory chain complexes(Ⅰ～Ⅳ)and autophagy-related proteins,while immunofluorescence staining was conducted to evaluate mitochondrial-lysosomal colocalization.In in vitro experiments,C2C12 myoblasts were differentiated into myotubes,and then divided into a control group(standard culture)and a cachexia group(co-cultured with KPC1199 cells for 48 h using transwell chambers).Mitochondrial-lysosomal colocalization and autophagy-related protein expression were analyzed with immunofluorescence assay and Western blotting.The mitochondrial division inhibitor Mdivi-1(20 μmol/L)was added to the co-culture system to assess its myotube diameter.Results Compared to the control mice,the cachectic mice exhibited mitochondrial swelling,reduced cristae density,and significantly increased mitochondrial-lysosomal colocalization in gastrocnemius muscle(P<0.05).Western blotting revealed the expression levels of mitochondrial respiratory chain proteins complexⅠ(1.00±0.04 vs 0.51±0.04,P<0.05),complexⅡ(1.00±0.13 vs 0.73±0.15,P<0.05),complexⅢ(1.00±0.20 vs 0.64±0.01,P<0.05),complexⅣ(1.00±0.06 vs 0.65±0.02,P<0.05)and PGC1α(1.00±0.03 vs 0.62±0.06,P<0.05)were decreased,and the levels of mitophagy markers,LC3-Ⅰ/Ⅱ(1.00±0.14 vs 1.65±0.25,P<0.05),PINK1(1.00±0.11 vs 1.51±0.05,P<0.05),and BNIP3(1.00±0.22 vs 2.02±0.10,P<0.05)were elevated when compared to the control.In the C2C12 myotube model,tumor cell co-culture increased mitochondrial-lysosomal colocalization and upregulated mitophagy-related protein expression(P<0.05),consistent with the in vivo findings.Mdivi-1 treatment increased myotube diameter from 220.6±35.5 μm to 315.0±39.1 μm(R2=0.666 5,P<0.05).Conclusion Mitophagy is activated in pancreatic cancer cachexia-induced muscle atrophy.Inhibiting mitophagy can effectively alleviate muscle atrophy induced by pancreatic cancer cachexia.

Objective To investigate the role and significance of neuropilin-2(NRP2)for regulating the angiogenesis of pancreatic neuroendocrine tumors(PNETs).Methods The NRP2 expression in pancreatic neuroendocrine tumer BON-1 cell line was intevened.The BON-1 cells cultural supernatants in the control group and interference group were used to treat human umbilical vein endothelial cells(HUVEC).CCK-8 was used to detect the cell proliferation,Transwell was used to detected the cell migration and the tubule formation test was used detect the pro-angiogenesis.Results The CCK-8 detection showed that there was no statistically significant difference in the supernatant treated HUVEC proliferations between the interference group and control group medium(P>0.05):the absorbancy in the control group was 0.35±0.04,while which in the interference group was 0.32±0.04.The Transwell test showed that the invasion ability of HUVEC treated with cultural supernatants in the interference group was weakened compared with the control group,the control group was(203±13)/hole,while the interference group was(100±10)/hole(P＜0.01);the tubule formation test showed that HUVEC tubular formation treated by cultural supernatant in the interference group was decreased,the control group was 40±5,while the interference group was 24±3(P＜0.01).Conclusion Interfering NRP2 expression of BON-1 cells can inhibit the vessel formation ability of co-cultured HUVEC,suggesting that NRP2 may have the pro-angiogenesis effect of PNETs,and may be a potential new target for the treatment of PNETs.

Standardized rotary residency training is an important part of clinical medical education. Traditional clinical teaching can't meet the rapid development of oncology medicine. In the rotary residency training in oncology department, we put forward the problems encountered in clinical practice, stimulate the interest and initiative of residence, the PBL teaching model is combined with the evidence-based medicine in the teaching process through the relevant training, literature review and discussion. By standardizing the treatment concept the residence's understanding of the basic theory and frontier knowledge of oncology was improved, the thinking innovation and clinical practice ability of the residency doctors were enhanced.

Objective To evaluatethe effect of mTORC1 inhibitor on the proliferation in human pancreatic neuroendocrine tumors(pNET)cell line BON,to explore the function of glutamine metabolism in it.Methods In vitro cultured human pancreatic neuroendocrine tumors(pNET)cell line BON,BON cells were treated with different concentrations of rapamycin(1,5,10,25,50, 100 nM)for 12,24 h.Then CCK-8 assay are used to calculate the growth inhibitory rate.Rapamycin treated with BON 12 h,test the glutamine uptake level compared with control.Then deprive of glucose and/or glutamine,CCK-8 assay were used in observation of cell proliferation,cell cycle distribution was analyzed by flow cytomety.Results Rapamycin significantly inhibited the growth of BON cells in a time-and dose-dependent manner(P <0.05).Meanwhile,rapamycin can reduce the glutamine uptake level compared with control.BON obviously depends on glutamine for growth,without glucose and glutamine group have obvious difference in growth rate(P <0.05).Conclusion mTORC1 inhibitor can inhibit BON cells proliferation and influence the glutamine uptake lev-el.suggesting that mTORC1 inhibitor might inhibit BON cells proliferation by influenced the glutamine metabolic pathway.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are exceedingly rare tumor,with an increasing incidence in recent years.According to the NANETS consensus guidelines for the diagnosis of neuroendocrine tumor,the algorithm for diagnosis of GEP-NENs includes clinical syndrome suggestive of NENs,biochemical testing,genetic testing,tumor localization by imaging and tissue diagnosis.GEP-NENs could be divided into functional versus non-functional based on the clinical manifestations.Radical surgery is the standard firstline therapy for limited-stage tumors.However,two-thirds of GEP-NENs patients are inoperable for tumor metastasis at initial diagnosis.For these advance staged patients,multidisciplinary treatment is the best choice,which includes surgery,chemotherapy,biotherapy,molecular targeted therapy,somatostatin receptor-targeted radionuclide therapy.Molecular targeted therapy may turn into a standard first-line therapy for its good curative effect in recent studies.

Objective To study the expression of splice variant of progesterone-induced blocking factor (PIBF) of healthy adult and hepatocellular carcinoma (HCC) patients. Methods Western blot was used to find out the expression in 3 normal livers and tumor and para-tumor tissue of 8 HCC patients. Use T Test to compare the difference. Immunohistochemistry was used to detect the expression in tumor and para-tumor tissue of 48 HCC patients. The splice variant of PIBF serum concentrations of 103 healthy adult, pre-operation and part of 5 days post-operation of 109 HCC patients was tested with ELISA. Result The expression of HCC tissue is lower than para-tumor tissue. The serum concentrations of healthy adult and HCC patients is 73.04 ± 6.29 ng/mL and 49.10 ± 4.07 ng/mL, and the difference was statistically significant (P=0.010). The analysis of blood concentrations of pre-operation and part of 5 days post-operation of 15 HCC patients indicate that the expression of pre-operation is lower than post-operation, and the difference was statistically significant (P = 0.008). Conclusion The splice variant of PIBF is low expressed in HCC tissue and serum. PIBF is a potential protein plays important role in cancer.

Objective: To examine the expression of glucocorticoid receptor in human colon cancinoma tis-sues and call lines and to explore the survival of colon cancer cell lines treated with dexamethasone alone or in combination with 5-Fu and L-OHP in a way of dexamethasone pretreatment or co-administration in vitro.Methods: The expression of glucocorticoid receptor was detected in 61 cases of colon cancer tissue samples and 4 types of colon cancer cell lines by immunohistochemistry. Apoptosis was detected by Hoechst33342 staining and flow cytometry. MTT assay was employed to detect the chemosensitivity of colon carcinoma cells to L-OHP and 5-Fu with dexamethasone pretreatment for 24 hours or co-administretion. Results: Positive GR expression was found in 57.3% colon cancer tissue samples and in Lovo and HCT-116 cell lines, not in HT-29 and SW-480. Apoptosis was detected in GR-expressed Lovo and HCT-116 cells at 72 hours after 1×10~(-4)mol/L Dex treatment, and the rates of apoptosis were higher than those in the control groups without Dex (P<0.01),GR-negative cells, HT-29 and SW-480 even treated with 1 × 10~(-4)mol/L Dex for 72 hours. Pretreatment and co-administration for Lovo cells with 1×10~(-4)mol/L Dex could decrease the IC50 of L-OHP from 13.7±1:1.3μg/mL to 5.9±0.6μg/mL and 4.8±0.7μg/mL, respectively. IC50 of 5-Fu was decreased from 72.2±8.1 μg/mL to 21.1±4.1μg/mL and 18.6±4.0μg/mL, respectively. Conclusion: There is expression of glucocorticoid receptor in part of colon carcinoma tissue samples and cell lines. Apoptosis does occur in GR-expressed Lovo and HCT-116 cells induced by dexamethasone in vitro. Pretreatment for 24h and co-administration with Dex can increase the chemosensitivity of Lovo cells to L-OHP and 5-Fu.

Objective To observe the inhibitory effect of Gefitinib,a selective oral epidermal growth factor receptor tyrosine kinase inhibitor,on the growth of human colon cancer cells,and investigate the relationship between the sensitivity of colon cancer cells to Gefitinib and PIEN expressions.Methods The inhibitory effects of Gefitinib on 6 kinds of colon cancer cells(Lovo,HCT116,HT29,Lsl74T,SW480 and SW620),the levels of PTEN mRNA in different colon cancer cells.and PTEN protein expressions in colon cancer cells were detected by MTT assay,RT-PCR and Westem blot,respectively.Results The inhibitory effects of Gefitinib on the 6 colon cancer cells in vitro varied a lot.When the concentration of Gefitinib was 1 μmol/L,LoVO cells had the most sensitivity to Gefitinib with an IC50＜10μmol/L;HT29 and SW480 had moderate sensitivity,and the IC50 ranged from 10 μnol/L to 100 μmol/L;HCT116,LS174T and SW620 were insensitive to Gefitinib,and their IC50＞100 μmol/L.All the colon cancer cell lines exhibited PTEN mRNA and protein expressions.Conclusions PTEN mRNA andprotein expressions might not be associated with the inhibitory effects of Gefitinib on the growth of colon cancer cells.The expression of PTEN can not be taken as the indication of the sensitivity of colon cancer cells to Gefitinib.

Medical education on oncology is urgently enhanced in China.We analyse a host of questions in medical education on oncology in our country at present,and study didactical methods,goal and task on oncology education.