漫谈消化系统心理问题的医源性因素

许多到消化科就诊的患者症状很多,很痛苦,花费大量医疗费用检查、用药,但是症状得不到缓解甚至加重,经过正规检查诊断后发现许多患者的诊治极不规范,因不规范的医学宣传、诊断、治疗给患者造成了极大的心理负担,产生了更多的心理性躯体症状。这种现状需要从医人员和医疗行政管理者及患者共同努力进行改进。

Advances in Gene Structure, Evolution and Function of Plac8

Placenta specific protein 8 （PLAC 8） also called onzin or C15, is a cys- teine-rich protein. It is widely distributed in eukaryotes, and its function has been extensively studied. It not only regulates cell division, differentiation, and apoptosis, but also plays an important role in the immune process. This article describes the latest progress of plac8 gene structure characteristics, evolution, expression and function and possible mechanisms.

Significance and relationship between Yes-associated protein and survivin expression in gastric carcinoma and precancerous lesions

AIM:To analyze the differences and relevance of Yes-associated protein (YAP) and survivin, and to explore the correlation and signifi cance of their expression in gastric carcinoma and precancerous lesions.METHODS: The PV9000 immunohistochemical method was used to detect the expression of YAP and survivin in 98 cases of normal gastric mucosa, 58 intestinal metaplasia (IM), 32 dysplasia and 98 gastric carcinoma.RESULTS: The positive rates of YAP in dysplasia (37.5%) and gastric carcinoma (48.0%) were significantly higher than that in normal gastric mucosa (13.3%), P<0.01. The positive rates of survivin in IM (53.4%), dysplasia (59.4%) and gastric carcinoma (65.3%) were significantly higher than in normal gastric mucosa (11.2%), P<0.01. Survivin expression gradually increased from 41.7% in well differentiated adenocarcinoma through 58.3% in moderately differentiated adenocarcinoma to 75.6% in poorly differentiated adenocarcinoma, with significant Rank correlation, rk=0.279, P<0.01. The positive rate of survivin in gastric carcinoma of diffused type (74.6%) was significantly higher than that in intestinal type (51.3%), P<0.05. In gastric carcinoma with lymph node metastasis (76.9%), the positive rate of survivin was signifi cantly higher than that in the group without lymph node metastasis (41.2%), P<0.01. In 98 cases of gastric carcinoma, the expression of YAP and of survivin were positively correlated, rk=0.246, P<0.01.CONCLUSION: YAP may play an important role as a carcinogenic factor and may induce survivin expression. Detecting both markers together may help in early diagnosis of gastric carcinoma.

Bacterial infections in cirrhotic patients with hepatocellular carcinoma

AIMS To establish the prevalence of bacterial infection in cir- rhotic patients with hepatocellular carcinoma(HCC). METHODS All 719 cirrhotic patients with HCC were investigat- ed retrospectively for the prevalence of bacterial infections. RESULTS The incidence of bacterial infection was 15.4% (111/719).According to Child-Pugh classification,the inci- dences of bacterial infection in class A,B and C were 2.3%,8. 0%,and 26.4 %,respectively.The bacterial infection increased with the severity of cirrhosis and severe bacterial infections usual- ly occurred in Child-Pugh class B and C patients. CONCLUSIONS The susceptibility of HCC patients to bacterial infection is mainly due to the underlying cirrhosis and not to the HCC itself.

Expression of HER2 and bradykinin B_1 receptors in precursor lesions of gallbladder carcinoma

AIM： To determine the expression of HER2 and bradykinin B1 receptors （B1R） in the two pathogenic models of gallbladder cancer： the metaplasia dysplasia carcino ma and the adenoma carcinoma pathways.METHODS： Receptor proteins were visualized by immunohistochemistry on 5-μm sections of paraffin-embedded tissue. Expression of both receptors was studied in biopsy samples from 92 patients （6 males and 86 females; age ranging from 28 to 86 years, mean 56 years）. High HER2 expression in specimens was additionally investigated by fluorescence in situ hybridization. Cell proliferation in each sample was assessed by using the Ki-67 proliferation marker.RESULTS： HER2 receptor protein was absent in adenomas and in normal gallbladder epithelium. On the contrary, there was intense staining for HER2 on the basolateral membrane of epithelial cells of intestinal metaplasia （22/24; 91.7%） and carcinoma in situ （9/10; 90%）, the lesions that displayed a significantly high proliferation index. Protein up-regulation of HER2 in the epithelium with metaplasia or carcinoma in s/tu was not accompanied by HER2 gene amplification. A similar result was observed in invasive carcinomas （0/12）. The B1R distribution pattern mirrored that of HER2 except that B1R was additionally observed in the adenomas. The B1R appeared either as cytoplasmic dots or labeling on the apical cell membrane of the cells composing the epithelia with intestinal metaplasia （24/24; 100%） and carcinoma in situ （10/10; 100%） and in the epithelial cells of adenomas. In contrast, both HER2 （4/12; 33%） and B1R （1/12; 8.3%） showed a low expression in inva- sive gallbladder carcinomas.CONCLUSION： The up-regulation of HER2 and B1R in precursor lesions of gallbladder carcinoma suggests cross-talk between these two receptors that may be of importance in the modulation of cell proliferation in gallbladder carcinogenesis,

Validation of a serum microRNA panel as biomarkers for early diagnosis of hepatocellular carcinoma post-hepatitis C infection in Egyptian patients

AIM To investigate the prospective importance of serum micro(mi)RNAs(mi R-125 b, mi R-138 b, mi R-1269, mi R-214-5p, mi R-494, mi R375 and mi R-145) as early biomarkers for the diagnosis of hepatitis C virus(HCV)-related hepatocellular carcinoma(HCC).METHODS Two-hundred and fifty HCV4 a patients, 224 HCV4 aHCC patients, and 84 healthy controls were enrolled in the study. Expression levels of mi R214-5p, mi R-125 b, mi R-1269 and mi R-375 were quantified using quantitative real-time PCR.RESULTS Expression of the selected mi RNAs in serum wassignificantly lower in HCC patients than in the healthy controls, except for mi R-1269 and mi R-494. There was a significant difference between HCC and HCV patients, in particular for HCC and late stage fibrosis, rather than HCV patients and early fibrosis. It is obvious that mi R-1269 was significantly upregulated in HCC cases compared to hepatic fibrosis cases. Each mi RNA can show HCC progression. Multivariate logistic regression analysis indicated that the tested panel of mi RNAs(mi R214-5p, mi R-125 b, mi R-1269 and mi R-375) represent accurate and specific indictors of HCC development.CONCLUSION This study presents a panel of mi RNAs with strong power as putative diagnostic and prognostic biomarkers for HCV-induced HCC. Moreover, mi R-214-5p and mi R-1269 could be considered as early biomarkers for tracking the progress of liver fibrosis to HCC.

Nano albumin bound-paclitaxel in pancreatic cancer: Current evidences and future directions

Pancreatic cancer(PDAC) is an aggressive and chemoresistant disease, representing the fourth cause of cancer related deaths in western countries. Majority of patients have unresectable, locally advanced or metastatic disease at time of diagnosis and the 5-year survival rate in these conditions is extremely low. For more than a decade gemcitabine has been the cornerstone of metastatic PDAC treatment, although survival benefit was very poor. PDAC cells are surrounded by an intense desmoplastic reaction that may create a barrier to the drugs penetration within the tumor. Recently PDAC stroma has been addressed as a potential therapeutic target. Nano albumin bound(Nab)-paclitaxel is an innovative molecule depleting tumor stroma, through interaction between albumin and secreted protein acidic and rich in cysteine. Addition of nab-paclitaxel to gemcitabine has showed activity and efficacy in metastatic PDAC first-line treatment improving survival and overall response rate vs gemcitabine alone in the MPACT phase Ⅲ study. This combination represents one of the standards of care in advanced PDAC therapy and is suitable to a broader spectrum of patients compared to other schedules. Nab-paclitaxel is under investigation as a backbone of chemotherapy in novel combinations with target agents or immunotherapy in locally advanced or metastatic PDAC. In this article, we provide an updated and critical overview about the role of nab-paclitaxel in PDAC treatment based on the latest advances in preclinical and clinical research. Furthermore, we focus on the use of nab-paclitaxel within the context of metastatic PDAC treatment landscape and we discuss about future implications in the light of current clinical ongoing trials.

Tumor suppressor gene p16 and Rb expression in gastric cardia precancerouslesions from subjects at a high incidence area in northern China

AIM:To further understand the molecular basis for gastric cardia carcinogenesis and to provide etiological clues. METHODS: Endoscopic mucosa biopsy and histopathological examinations were made on 37 subjects from a high incidence area for both esophageal and gastric cardia carcinomas in northern China. All the biopsy samples were fixed in 850 ml. (-1)L alcohol and embedded in paraffin. Each block contained one piece of tissue and was serially section at 5 microm. Immunohistochemistry (ABC) was carried out on these gastric cardia samples to determine the alterations of p16 and Rb. RESULTS: Based on the histopathlogical examination there were 11 cases of chronic superficial gastritis, 12 cases of chronic atrophic gastritis and 14 cases of dysplasia. The immunostaining demonstrated different levels of unclear immunostaining of p16 and Rb in normal gastric cardia tissue and the tissues with different severity of lesions. With the lesions progressing, the positive immunostaining rates for p16 protein had a decreasing tendency. In contrast, the positive immunostaining rate for Rb protein had an increasing tendency. There was a significant negative relationship between the two parameters. Changes of p16 was CSG 11(100%), CAG 7(58%), DYS 4(29%) and changes of Rb was CSG 2(18%), CAG 8(67%) and DYS 12(86%), (P【0.05). CONCLUSION: The alterations of p16 and Rb protein may play a role in the early stages of gastric cardia carcinogenesis.

EFFECTS OF MUTATION AND EXPRESSION OF PTEN GENEmRNA ON TUMORIGENESIS AND PROGRESSION OFEPITHELIAL OVARIAN CANCER

Objective To investigate the mutation and expression of tumor suppressor gene-PTEN mRNA and explore their roles in tumorigenesis and progression of ovarian cancer. Methods Mutated exon 5 of PTEN gene was examined in normal ovary(n = 5), ovarian cyst (n =5), ovarian borderline tumor (n = 9), epithelial ovarian cancer(n = 60), and ovarian cancer cell line (n = 1)by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). mRNA expression of PTEN gene was evaluated in corresponding tissues and cell line by reverse transcription polymerase chain reaction(RT-PCR). The mutation and mRNA expression of PTEN gene were compared with clini-copathological features of ovarian cancer. Results Mutated exon 5 of PTEN gene was detected only in 5(7.1%)cases of epithelial ovarian cancer. mRNA expression level of PTEN gene in ovarian borderline tumor or ovarian cancer was lower than that in normal ovary or ovarian cyst(P < 0.05). The level of PTEN gene mRNA expression was negatively correlated with clinicopathological staging of ovarian cancer, whereas positively correlated with histological differentiation (P < 0.05). mRNA expression level of PTEN gene in ovarian endometrioid cancer was significantly lower than that in ovarian serous or mucinous cancer (P < 0.05=. Conclusions Mutation of PTEN gene occurs in ovarian cancer. Down-regulated expression of PTEN is probably an important molecular event in tumorigenesis of ovarian cancer. Abnormal expression of PTEN gene is involved in progression of ovarian cancer. Reduced expression of PTEN gene is closely associated with tumorigenesis and pathobiological behaviors of ovarian endometrioid cancer.

Lack of CD44 variant 6 expression in rectal cancer invasive front associates with early recurrence

AIM: To investigate the prognostic value of CD44 variant 6 (CD44v6), a membranous adhesion molecule, in rectal cancer. METHODS: Altogether, 210 rectal cancer samples from 214 patients treated with short-course radiotherapy (RT, n = 90), long-course (chemo) RT (n = 53) or surgery alone (n = 71) were studied with immunohistochemistry for CD44v6. The extent and intensity of membranous and cytoplasmic CD44v6 staining, and the intratumoral membranous staining pattern, were analyzed.RESULTS: Membranous CD44v6 expression was seen in 84% and cytoplasmic expression in 81% of the cases. In 59% of the tumors with membranous CD44v6 expression, the staining pattern in the invasive front was determined as "front-positive" and in 41% as "front-negative". The latter pattern was associated with narrower circumferential margin (P = 0.01), infiltrative growth pattern (P < 0.001), and shorter disease-free survival in univariate survival analysis (P = 0.022) when compared to the "front-positive" tumors. CONCLUSION: The lack of membranous CD44v6 in the rectal cancer invasive front could be used as a method to identify patients at increased risk for recurrent disease.

A rare case of periampullary carcinoma with ectopic ending of Vater's ampulla

A 71-year-old woman was referred to our department complaining of painless progressive jaundice for the last 3 too. Magnetic resonance imaging and magnetic resonance cholangiopancreatography （MRCP） showed the ectopic hepatopancreatic ampulla draining into the fourth part of the duodenum adjacent to the duodenojejunal flexure; the irregular morphology of the duodenojejunal flexure likely due to a soft tissue mass. Laparotomy confirmed the presence of the abnormal ampulla of Vater located at the fourth part of the duodenum and a soft tissue tumor about 6 cm × 5 cm×5 cm with a peduncle adjoining the ampulla. Resection of the tumor, including some peripheral tissue, and a Roux-Y loop anastomosis choledochojejunostomy were performed. Pathological examination indicated an intestinal villous adenoma accompanied by severe dysplasia and focal canceration. Periampullary carcinoma with ectopic ending of the Vater＇s ampulla into the fourth part of the duodenum is rather rare. The embryonic genetic background of this anomaly has not yet been fully explained. It is worth mentioning that MRCP is useful for demonstrating anomalies and anatomic variants of the biliary tract system and pancreatic duct.

Effects of San Qi on Gastric Secretion and Protective Factors of Gastric Mucosa in the Rat with Precancerous Lesion of Stomach

In the model rat with precancerous lesion of stomach induced by the combined method of insertion of a spring into the pylorus and high salt hot paste,effects of San Qi (三七 Radix Notoginseng) on gastric secretion and protective factors of stomach were investigated.The results indicated that gastric secretion,gastric mucosal blood flow (GMBF) and aminohexose content lowered significantly,and malondialdehyde (MDA) increased significantly (P<0.01) in the model group as compared with the normal group;after treatment with San Qi Powder for 12 weeks,both gastric secresion and GMBF increased,and MDA content decreased as compared with the negative control group (P<0.01),with no significant increase of aminohexose content.It is suggested that San Qi (三七 Radix Notoginseng) may improve gastric secretion,and that increase of GMBF and antagonism against the lesion of oxygen free radicals are possibly one of its mechanisms.

Microsatellite instability in gastric cancer and pre-cancerous lesions

AIM: To investigate the microsatellite instability (MSI) in cancer and pre-cancerous lesions of the stomach and its mechanisms underlying the development of gastric cancer.METHODS: Thirty-six gastric cancer samples were obtained from patients undergoing surgery. Forty-one gastric mucosa samples with dysplasia and 51 with intestinal metaplasia (IM) were obtained from patients with chronic gastritis undergoing gastro-endoscopy. Genomic DNA was extracted from the samples. Silver staining single strand conformation polymorphis-polymerize chain reaction (SSCP-PCR) was used to screen MSI markers at 5 loci (Bat-25, Bat-26, D5S346, D17S250, and D2S123)in fresh tissues and formalin-fixed, paraffin-embedded samples and their corresponding normal gastric mucosa.RESULTS: The abnormal shifting of the single-strand DNA (MSI) was identified in 21 out of 36 (58.3%) gastric cancers.Seven cases showed high-level MSI (two or more loci altered) and 14 showed low-level MSI (one locus altered).Gastric cancer with MSI had a tendency to be located in the distal stomach. MSI was also detected in 11 out of 41(26.8%) dysplasia samples and in 9 of 51 (17.6%) IM samples respectively. Three cases of dysplasia and one case of IM showed high-level MSI. Eight cases of dysplasia and 8 cases of IM displayed low-level MSI. MIS in IM was found only in moderate or severe-grade IM. No association was detected between MSI and dysplasia grade.CONCLUSION: Accumulation of MSI in dysplasia and intestinal metaplasia of gastric mucosa may be an early molecular event during gastric carcinogenesis and may contribute to the acquisition of transformed cell phenotype and the development of gastric cancer.

Expression and significance of homeodomain protein Cdx2 in gastric carcinoma and precancerous lesions

AIM： To investigate the expression and significance of caudal-related homeobox transcription factor （Cdx2） in gastric carcinoma （GC） and precancerous lesions. METHODS： The expression of Cdx2 in GC, precancer- ous lesions and normal gastric mucosa were detected using immunohistochemical method. Hematoxylin and eosin staining, alcian blue/periodic acid-schiff and high iron diamine/alcian blue staining were used to classify intestinal metaplasia （IM） and GC. RESULTS： Cdx2 was not detected in normal gas- tric mucosa. Cdx2 expression was detected in 87.1% （101/116） of IM, 50% （36/72） of dysplasia and 48.2% （41/85） of GC. The Cdx2-expressing cells in IM were more prevalent than in dysplasia and carcinoma （P 〈 0.05）. There was no relationship between Cdx2 ex- pression and the classification of IM or the degree of dysplasia. Expression of Cdx2 was significantly higher in intestinal-type carcinoma than in diffuse and mixed- type carcinoma （P 〈 0.05）. Positive expression of Cdx2was mainly found in moderately to well differentiated GC. There was a negative association between nuclear Cdx2 expression and lymph node metastasis and tumor, nodes, metastasis stage of GC （P 〈 0.05）. The patients with Cdx2-positive expression showed a higher survival rate than those with Cdx2-negative expression （P = 0.038）. Multivariate analysis revealed that the expres- sion of Cdx2 and lymph node metastasis were indepen- dent prognostic indicators of GC （P 〈 0.05）.

Review:Lipids changes in liver cancer

Liver is one of the most important organs in energy metabolism. Most plasma apolipoproteins and endogenous lipids and lipoproteins are synthesized in the liver. It depends on the integrity of liver cellular function, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs, these processes are impaired and the plasma lipid and lipoprotein patterns may be changed. Liver cancer is the fifth common malignant tumor worldwide, and is closely related to the infections of hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV infections are quite common in China and other Southeast Asian countries. In addition, liver cancer is often followed by a procession of chronic hepatitis or cirrhosis, so that hepatic function is damaged obviously on these bases, which may significantly influence lipid and lipoprotein metabolism in vivo. In this review we summarize the clinical significance of lipid and lipoprotein metabolism under liver cancer.

The expressions of Bcl-2 and Bax in gastric carcinoma and precancerous lesions

Objective: To study the expressions of Bcl-2 and Bax proteins and explore the relationships between them and apoptosis in gastric carcinoma and precancerous lesions. Methods: TUNEL method was used to detect apoptosis and im- munohistochemical staining method was used to detect the expressions of Bcl-2 and Bax proteins in 70 cases of chronic gastritis, 49 cases of intestinal metaplasia, 64 cases of dysplasia and 81 cases of gastric carcinoma. Results: The positive incidences of Bcl-2 and Bax were the highest in severe dysplasia. In intestinal metaplasia and dysplasia, positive incidences of Bcl-2 and Bax were higher than those in chronic gastritis and gastric carcinoma. During the process of evolvement from chronic gastritis to intestinal metaplasia then to dysplasia, apoptosis indexes gradually rise up to mid-high dysplasia, which reached the highest point, then it began to fall down, when it reached the lowest point in gastric carcinoma. There were nega- tive correlations between the expressions of Bcl-2, Bax proteins and apoptosis. Conclusion: The expression of Bcl-2 may be an early behavior in the gastric carcinogenesis. Bax had antagonistic effect to Bcl-2. Detections of Bcl-2 and Bax may be beneficial to the early diagnosis of gastric tumor and precancerous lesions.

Progression of diethylnitrosamine-induced hepatic carcinogenesis in carnitine-depleted rats

AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six groups with 10 animals in each group.Rats in group 1(control group)received a single intraperitoneal(i.p.)injection of normal saline. Animals in group 2(carnitine-supplemented group) were given L-carnitine(200 mg/kg per day)in drinking water for 8 wk.Animals in group 3(carnitine-depleted group)were given D-carnitine(200 mg/kg per day)and mildronate(200 mg/kg per day)in drinking water for 8 wk.Rats in group 4(DENA group)were injected with a single dose of DENA(200 mg/kg,i.p.)and 2 wk later received a single dose of carbon tetrachloride(2 mL/kg) by gavage as 1:1 dilution in corn oil.Animals in group 5(DENA-carnitine depleted group)received the same treatment as group 3 and group 4.Rats in group 6 (DENA-carnitine supplemented group)received the same treatment as group 2 and group 4.RESULTS:Administration of DENA resulted in a significant increase in alanine transaminase(ALT), gamma-glutamyl transferase(G-GT),alkaline phosphatase(ALP),total bilirubin,thiobarbituric acid reactive substances(TBARS)and total nitrate/ nitrite(NOx)and a significant decrease in reduced glutathione(GSH),glutathione peroxidase(GSHPx), catalase(CAT)and total carnitine content in liver tissues.In the carnitine-depleted rat model,DENA induced a dramatic increase in serum ALT,G-GT,ALP and total bilirubin,as well as a progressive reduction in total carnitine content in liver tissues.Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes,TBARS and NOx,and a decrease in total carnitine,GSH,GSHPx, and CAT induced by DENA,compared with the control values.Histopathological examination of liver tissues confirmed the biochemical data,where L-carnitine prevented DENA-induced hepatic carcinogenesis while D-carnitine-mildronate aggravated DENA-induced hepatic damage. CONCLUSION:Data from this study suggest for the first time that:(1)carnitine deficiency is a risk factor and should be viewed as a mechanism in DENA- induced hepatic carcinogenesis;(2)oxidative stress plays an important role but is not the only cause of DENA-induced hepatic carcinogenesis;and(3) long-term L-carnitine supplementation prevents the development of DENA-induced liver cancer.

Possibility of non-invasive diagnosis of gastric mucosal precancerous changes

AIM: To assess the possibility of non-invasive screening of atrophic chronic gastritis for preventing further development of gastric cancer.METHODS: One hundred and seventy-eight consecutive Helicobacter pylori ( H pylori)-positive dyspeptic patients after detection of serum levels of pepsinogen-1 (PG-1) and gastrin-17 (G-17) by enzyme immunoassay were proposed for endoscopy and histology. The serologic and morphologic results were compared with estimating the sensitivity, specificity and prognostic values of the tests.RESULTS: There was statistically significant reverse dependence between the grade of stomach mucosal antral or corpus atrophy and the proper decreasing of serum G17 or PG1 levels. The serologic method was quite sensitive in the diagnosis of non-atrophic and severe antral and corpus gastritis. Also, it was characterized by the high positive and negative prognostic values.CONCLUSION: Detection of serum G-17 and PG1 levels can be offered as the screening tool for atrophic gastritis. The positive serologic results require further chromoendoscopy with mucosal biopsy, for revealing probable progressing of atrophic process with development of intestinal metaplasia, dysplasia or gastric cancer.

miR-34a mediates oxaliplatin resistance of colorectal cancer cells by inhibiting macroautophagy via transforming growth factor-β/Smad4 pathway

To investigate whether microRNA (miR)-34a mediates oxaliplatin (OXA) resistance of colorectal cancer (CRC) cells by inhibiting macroautophagy via the transforming growth factor (TGF)-β/Smad4 pathway.METHODSmiR-34a expression levels were detected in CRC tissues and CRC cell lines by quantitative real-time polymerase chain reaction. Computational search, functional luciferase assay and western blotting were used to demonstrate the downstream target of miR-34a in CRC cells. Cell viability was measured with Cell Counting Kit-8. Apoptosis and macroautophagy of CRC cells were analyzed by flow cytometry and transmission electron microscopy, and expression of beclin I and LC3-II was detected by western blotting.RESULTSExpression of miR-34a was significantly reduced while expression of TGF-β and Smad4 was increased in CRC patients treated with OXA-based chemotherapy. OXA treatment also resulted in decreased miR-34a levels and increased TGF-β and Smad4 levels in both parental cells and the OXA-resistant CRC cells. Activation of macroautophagy contributed to OXA resistance in CRC cells. Expression levels of Smad4 and miR-34a in CRC patients had a significant inverse correlation and overexpressing miR-34a inhibited macroautophagy activation by directly targeting Smad4 through the TGF-β/Smad4 pathway. OXA-induced downregulation of miR-34a and increased drug resistance by activating macroautophagy in CRC cells.CONCLUSIONmiR-34a mediates OXA resistance of CRC by inhibiting macroautophagy via the TGF-β/Smad4 pathway.

Oncogenic Role of Skp2 and p27^(Kip1) in Intraductal Proliferative Lesions of the Breast

Objective To investigate whether the connection of p27 Kip1 to S-phase kinase-associated protein 2 (Skp2) plays an oncogenic role in intraductal proliferative lesions of the breast. Methods Here we investigated the mechanism involved in association of Skp2's degradation of p27 Kip1 with the breast carcinogenesis by immunohistochemical method through detection of Skp2 and p27 Kip1 protein levels in 120 paraffin-embedded tissues of intraductal proliferative lesions including usual ductal hyperplasia (UDH, n=30), atypical ductal hyperplasia (n=30), flat epithelial atypia (FEA, n=30), and ductal carcinoma in situ (DCIS, n=30). Moreover, the expression status of Skp2 and p27 Kip1 in 30 cases of the normal breast paraffin-embedded tissues were explored. Results The DCIS group was with the highest Skp2 level and the lowest p27 Kip1 level, and the UDH group was with the lowest Skp2 level and the highest p27 Kip1 level. Both Skp2 and p27 Kip1 levels in the DCIS group were significantly different from those in the UDH group (all P<0.01). The levels of Skp2 and p27 Kip1 in the FEA group were significantly different from both the DCIS and UDH groups (all P<0.05). p27 Kip1 was negatively correlated with Skp2 in both the UDH group (r=-0.629, P=0.026) and DCIS group (r=-0.893, P=0.000). Conclusion Overexpression of Skp2 might be the mechanism underlying p27 Kip1 over degradation.