Efficacy and safety of dacomitinib as first-line treatment for advanced non-small cell lung cancer patients with epidermal growth factor receptor 21L858R mutation:A multicenter,case-series study in China

Objective:To provide real-world evidence for the application of first-line dacomitinib treatment for epidermal growth factor receptor(EGFR)21L858R mutant non-small cell lung cancer(NSCLC)patients in China and to explore the factors influencing the efficacy and safety.Methods:A longitudinal,consecutive case-series,multicenter study with mixed prospective and retrospective data was conducted.The primary endpoint was progression-free survival(PFS),and the secondary endpoints included duration of treatment(DOT),overall survival(OS),objective response rate(ORR),disease control rate(DCR)and safety.Results:A total of 155 EGFR 21L858R mutant patients treated with first-line dacomitinib were included.The median follow-up time for these patients was 20.4 months.Among 134 patients with evaluable lesions,the ORR was 70.9%and the DCR was 96.3%.The median PFS was 16.3[95%confidence interval(95%CI),13.7−18.9]months.Multivariate Cox regression analysis suggested that the baseline brain metastasis(BM)status[with vs.without BM:hazard ratio(HR),1.331;95%CI,0.720−2.458;P=0.361]and initial doses(45 mg vs.30 mg:HR,0.837;95%CI,0.427−1.641;P=0.604)did not significantly affect the median PFS.The median DOT was 21.0(95%CI,17.5−24.6)months and the median OS was not reached.Genetic tests were performed in 64 patients after progression,among whom 29(45.3%)patients developed the EGFR 20T790M mutation.In addition,among the 46 patients who discontinued dacomitinib treatment after progression,31(67.4%)patients received subsequent third-generation EGFR-tyrosine kinase inhibitors.The most common grade 3−4 adverse events were rash(10.4%),diarrhea(9.1%),stomatitis(7.1%)and paronychia(4.5%).The incidence of grade 3−4 rash was significantly higher in the 45 mg group than that in the 30 mg group(21.9%vs.7.5%,P=0.042).Conclusions:First-line dacomitinib treatment demonstrated promising efficacy and tolerable adverse events among EGFR 21L858R mutant NSCLC patients in China.

SARS尸检的肺部病理改变

目的通过研究严重急性呼吸综合征(severeacuterespiratorysyndrome,SARS)患者的尸检肺部标本,总结SARS的肺部病变特点及发病机制。方法详细检查SARS患者肺脏标本的大体特点,并用常规方法研究显微光镜下SARS累及各肺叶的病变特点。结果7例SARS患者的双肺均明显膨胀,镜下表现以弥漫性肺泡损伤(DAD)不同时期的病变为主。7例均有肺水肿及透明膜形成,肺水肿尤以早期明显。病程超过3周者开始有肺泡内机化及肺间质纤维化,造成肺泡的纤维性闭塞。几乎每例都可见到小血管内的微血栓和肺出血、散在的小叶性肺炎、肺泡上皮脱落、增生等病变。2例可见曲霉菌感染,1例累及左全肺及右肺部分区域,1例出现在肺门淋巴结。肺门淋巴结多表现为充血、出血及淋巴组织减少,窦组织细胞增多。结论SARS肺可能为SARS病毒造成的弥漫性肺泡损伤,表现为肺泡上皮及毛细血管的严重损伤导致肺水肿和肺泡及细支气管的纤维素性渗出性炎症,出现透明膜,继而出现肺泡内机化及肺泡间隔的成纤维细胞增生,共同使肺泡萎陷、机化,最终形成纤维化实变。肺门淋巴组织的减少可能是此病影响免疫系统的又一形态学表现。

Methylation profile of the promoter CpG islands of 31 genes that may contribute to colorectal carcinogenesis

AIM: To establish the methylation profile of the promoter CpG islands of 31 genes that might play etiological roles in colon carcinogenesis.METHODS: The methylation specific PCR in conjunction of sequendng verification was used to establish the methylationprofile of the promoter CpG islands of 31 genes in colorectal cancer (n = 65), the neighboring non-cancerous tissues (n = 5), colorectal adenoma (n = 8), and normal mucosa (n = 1). Immunohistochemically, expression of 10 genes was assessed on the home-made tissue microarrays of tissues from 58 patients. The correlation of tumor specific changes with each of clinical-pathologic features was scrutinized with relevant statistic tools.RESULTS: In comparison with the normal mucosa of the non-cancer patients, the following 14 genes displayed no tumor associated changes: breast cancer 1, early onset (BRCA1), cadherin 1, type 1, E-cadherin (epithelial) (CDH1),death-associated protein kinase 1 (DAPK1), DNA (cytosine-5-)-methyltransferase 1 (DNMT1), melanoma antigen, family A, 1 (directs expression of antigen MZ2-E) (MAGEA1), tumor suppressor candidate 3 (N33), cyclin-dependent kinase inhibitor 1A (p21, Cipl) (p21^WAF1), cyclin-dependent kinase inhibitor 1B (p27, 10pl) (p27^WAF1), phosphatase and tensin hornolog (mutated in multiple advanced cancers 1) (PTEN), retinoic acid receptor, beta (RAR-, Ras association (RaIGDS/AF-6) domain family 1 C (RASSFIC), secreted frizzled-related protein 1 (SFRP1), tissue inhibitor of metalloproteinase 3 (Sorsby fundus dystrophy, pseudoinfiammatory) (TIMP3),and von HippeI-Lindau syndrome (VHL). The rest 17 targets exhibited to various extents the tumor associated changes.As changes in methylation of the following genes occurred marginally, their impact on the formation of colorectal cancer were trivial: adenomatous polyposis coli (APC) (8%, 5165),Ras association (RaIGDS/AF-6) domain family 1A (RASSFIA) (3%, 2/65) and cyclin-dependent kinase inhibitor 2A,alternated reading frame Co14~) (6%, 4/65). The following genes exhibited moderate changes in rnethylation: O-6rnethylguanine-DNA rnethyltransferase (MGMT) (20%, 13/65),rnutL hornolog 1, colon cancer, nonpolyposis type 2 (E. coli) (hMLH1) (18%, 12/65), cyclin-dependent kinase inhibitor 2A (melanoma, p16, inhibits CDK4) P16^NK4a) (10%, 10/65),rnethylated in tumor 1 (MINT1) (15%, 10/65), methylated in tumor 31 (MINT31) (11%, 7/65). The rest changed greatly in the rnethylation pattern in colorectal cancer (CRC): cyclin A1 (cyclin al) (100%, 65/65), caudal type homeobox transcriptdon factor 1 (CDX1) (100%, 65/65), RAR(85%, 55/65), myogenic factor 3 (MYOD1) (69%, 45/65),cyclin-dependent kinase inhibitor 2B (p15, inhibits CDK4)(p15^INK4b) (68%, 44/65), prostaglandin-endoperoxide synthase 2 (prostaglandin G/H synthase and cyclooxygenase) (COX2) (72%, 47/65), cadherin 13, H-cadherin (heart) (CDH13) (65%, 42/65), CAAX box 1 (OO~/) (58%, 38/65),tumor protein p73 (p73) (63%, 41/65) and Wilrns tumor 1 (WT/) (58%, 38/65). However, no significant correlation of changes in rnethylation with any given clinical-pathological features was detected. Furthermore, the frequent changes in rnethylation appeared to be an early phase event of colon carcinogenesis. The in situ expression of 10 genes was assessed by the irnrnunohistochernical approach at the protein level: CDH1, CDH13, COX2, cyclin A1, hMLH1,MGMT, p14^ARF, p73, RAR-, and TIMP3 genes in the context of the rnethylation status in colorectal cancer. No clear correlation between the hyperrnethylation of the promoter CpG islands and the negative expression of the genes was established.CONCLUSION: The methylation profile of 31 genes was established in patients with colon cancer and colorectal adenornas, which provides new insights into the DNA rnethylation mediated mechanisms underlying the carcinogenesis of colorectal cancer and may be of prognostic values for colorectal cancer.

Pathobiological behavior and molecular mechanism of signet ring cell carcinoma and mucinous adenocarcinoma of the stomach:A comparative study

AIM:To elucidate the distinctive pathobiological behavior between signet ring cell carcinoma (SRC) and mucinous adenocarcinoma of the stomach.METHODS: Based on the histological growth patterns and cell-functional differentiation classifications of stomach carcinoma, we conducted a series of comparative studies.All paraffin-embedded and frozen blocks were collected from the files of Cancer Institute of China Medical University. On the basis of histopathological observation, we applied enzymatic and mucous histochemistry, immunohistochemistry,flow cytometry (FCM) and molecular biology to compare these two categories of gastric cancers in terms of the DNA ploidy, proliferative kinetics, the expression of gastric carcinoma associated gene product and instabilities of mitochondrial DNA (mtDNA).RESULTS:Gastric SRC was commonly seen in females below 45 years, mostly presenting diffuse growth and ovary or uterine cervix metastasis. The majority of SRC were absorptive and mucus-producing functional differentiation type (AMPFDT), which growth relied on estrogen. Meanwhile,stomach mucinous adenocarcinomas were mostly observed in males over 50 years, prone to massive growth or nest growth and extensive peritoneal infiltration, showing two categories of cell-functional differentiation types: AMPFDT and mucus-secreting functional differentiation type (MSFDT).Expressions of ER, enzyme c-PDE and 67kDaLN-R in SRC were evidently higher than that in mucinous adenocarcinoma,while expressions of LN, CN-Ⅳ, CD44v6, and PTEN protein were obviously lower in SRC than that in mucinous adenocarcinoma (P<0.05).There was no statistic significance in VEGF, ECD and instabilities of mtDNA (P>0.05) between the above two gastric carcinomas.CONCLUSION: Though SRC and mucinous adenocarcinoma were both characterized by abundant mucus-secretion, they were quite different in morphology, ultrastructure, cell-functional differentiation and protein expression, indicating different mechanisms of carcinogenesis. We concluded that combining histological growth patterns, cell-functional differentiation type with tumor related markers might be significant in early diagnosis and prognosis assessment for SRC and mucinous adenocarcinoma of the stomach.

Treatment for liver metastases from breast cancer: Results and prognostic factors

AIM: Liver metastases from breast cancer (BCLM) are associated with poor prognosis. Cytotoxic chemotherapy can result in regression of tumor lesions and a decrease in symptoms. Available data, in the literature, also suggest a subgroup of patients may benefit from surgery, but few talked about transcatheter arterial chemoembolization (TACE). We report the results of TACE and systemic chemotherapy for patients with liver metastases from breast cancer and evaluate the prognostic factors. METHODS: Forty-eight patients with liver metastases, from proved breast primary cancer were treated with TACE or systemic chemotherapy between January 1995 and December 2000. Treatment results were assessed according to WHO criteria, along with analysis of prognostic factors for survival using Cox regression model. RESULTS: The median follow-up was 28 mo (1-72 mo). Response rates were calculated for the TACE group and chemotherapy group, being 35.7% and 7.1%, respectively. The difference was significant. The one-, two- and three-year Survival rates for the TACE group were 63.04%, 30.35%, and 13.01%, and those for the systemic chemotherapy group were 33.88%, 11.29%, and 0%. According to univariate analysis, variables significantly associated with survival were the lymph node status of the primary cancer, the clinical stage of liver metastases, the Child-Pugh grade, loss of weight. Other factors such as age, the intervals between the primary to the metastases, the maximal diameter of the liver metastases, the number of liver metastases, extrahepatic metastasis showed no prognostic significances. These factors mentioned above such as the lymph node status of the primary cancer, the clinical stage of liver metastases, the Child-Pugh grade, loss of weight were also independent factors in multivariate analysis. CONCLUSION: TACE treatment of liver metastases from breast cancer may prolong survival in certain patients. This approach offers new promise for the curative treatment of the patients with metastatic breast cancer.

Transcatheter arterial chemoembolization for gastrointestinal stromal tumors with liver metastases

AIM:To evaluate the efficacy and safety of transcatheter arterial chemoembolization(TACE) for gastrointestinal stromal tumor(GIST) with liver metastases after the failure of tyrosine kinase inhibitors(TKIs).METHODS:Patients with histologically confirmed CD117-positive GIST with liver metastases who were resistant and/or intolerant to prior imatinib and/or sunitinib and who received TACE for at least one treatment cycle or only best supportive care and TKI reintroduction were eligible for the study.The patients were divided into two groups:those in TACE group received TACE treatment containing 5-20 mL iodized oil and 40-80 mg doxorubicin hydrochloride and TKI reintroduction or best supportive care,those in control group only received TKI reintroduction or best supportive care.The primary end-point was overall survival and the secondary end-points were,progression-free survival(PFS),response rates,and safety.RESULTS:Sixty patients admitted between June 2008 and October 2011 were eligible for this study,including 22 in TACE group and 38 in control group.In the TACE group,12(54.5%) achieved liver partial response,5(22.7%) had stable disease,and 5(22.7%) had liver progressive disease.Disease control rate of liver metastases was 77.3% in the TACE group and 39.5% in the control group.The median liver PFS in TACE group was 47.1 wk(95% CI:23.9-70.3).The median PFS in TACE group was longer than in control group(30.0 wk,95% CI:20.1-39.9 vs 12.9 wk,95% CI:11.9-13.9)(P = 0.0001).The median overall survival in TACE group was also longer than in control group(68.5 wk,95% CI:57.4-79.6 vs 25.7 wk,95% CI:23.2-28.2)(P = 0.0001).TACE treatment significantly reduced the risk of death(hazard ratio:0.109).Patients without extrahepatic metastases treated with TACE had significantly better prognosis.Most of the adverse events were of grade 1 or 2 and tolerable.CONCLUSION:TACE is effective and well tolerated in GIST patients with liver metastases after TKI failure,and it may be an optional treatment for this disease.

Expression of e-cadherin and β-catenin in human esophageal squamous cell carcinoma: relationships with prognosis

AIM: To elucidate the expression of E-cadherin and β-catenincorrelating with its clinical outcome in patients withesophageal squamous cell carcinoma (ESCC), by analyzingtheir interrelationship with clinicopathological variables andtheir effects on progress and prognosis.METHODS: Expression of E-cadherin and β-catenin wasdetermined by SP immunohistochemical technique inpatients with ESCC consecutively, their correlation withclinical characteristics was evaluated and analyzed bymultivariate analysis.RESULTS: The rate of expression of E-cadherin decreasedto 66.03 % (70/106) in ESCC and the protein level wasnegative correlated with histologic grade, tumor size, clinicalstaging, lymph node metastasis and venous invasion.Whereas the expression rate of β-catenin was reduced to69.8 % (74/106) and the level of protein expressioncorrelated only with histologic grade. There obviously existedinverse correlation between level of E-cadherin protein andsurvival, especially in .stage I, IIa, IIb (P=0.0033), Patientswith low-expressing tumors for β-catenin and non-expressingtumors for E-cadherin/β-catenin had lower survival periodthan those with normal-expressing ones (P=0.0501 andP=0.0080, respectively). Patients with diminished expressionof E-cadherin as grade Ⅱ or Ⅲ had shorter survival periodthan those with normally expressing and grade Ⅰ, nosignificance existed between grade I and grade Ⅱ or Ⅲwith respect to different status of E-cadherin expression.Furthermore, Correlation analysis showed level of E-cadherincorrelated with that of β-catenin (P=0.005). Cox proportionalhazards model analysis suggested downregulation of E-cadherin was an important factor indicating poor prognosis.CONCLUSION: As a probable independent prognosticfactor, it correlates with overall and disease free survivalperiod, expression of E-cadherin but not β-catenin maypredict prognosis in patients with ESCC.

Sequential use of transarterial chemoembolization and percutaneous cryosurgery for hepatocellular carcinoma

AIM: To evaluate the efficacy of sequential use of transarterial chemoembolization (TACE) and percutaneous cryosurgery for unresectable hepatocellular carcinoma (HCC). METHODS: Four hundred and twenty patients were enrolled in this study. The patients, who were considered to have unresectable tumors due to their location or size or comorbidity, were divided into sequential TACE-cryosurgery (sequential) group (n = 290) and cryosurgery alone (cryoalone) group (n = 130). Patients in the sequential group tended to have larger tumors and a greater number of tumors than those in the cryo-alone group. Tumors larger than 10 cm in diameter were only seen in the sequential group. TACE was performed with the routine technique and percutaneous cryosurgery was conducted under the guidance of ultrasound 2-4 wk after TACE. RESULTS: During a mean follow-up period of 42 ± 17 mo (range, 24-70 mo), the local recurrence rateat the ablated area was 17% for all patients, 11% and 23% for patients in sequential group and cryoalone groups, respectively (P = 0.001). The overall 1-, 2-, 3-, 4and 5-year survival rate was 72%, 57%, 47%, 39% and 31%, respectively. The 1and 2-year survival rates (71% and 61%) in sequential group were similar to those (73% and 54%) in cryo-alone group (P = 0.69 and 0.147), while the 4and 5-year survival rates were 49% and 39% in sequential group, higher than those (29% and 23%) in cryo-alone group (P = 0.001). Eighteen patients with large HCC (> 5 cm in diameter) survived for more than 5 years after sequential TACE while no patient with large HCC (> 5 cm in diameter) survived more than 5 years after cryosurgery. The overall complication rate was 24%, and the complication rates were 21% and 26% for the sequential and cryo-alone groups, respectively (P = 0.06). The incidence of hepatic bleeding was higher in cryo-alone group than in sequential group (P = 0.02). Liver crack only occurred in two patients of the cryoalone group. CONCLUSION: Pre-cryosurgical TACE can increase the cryoablation efficacy and decrease its adverse effects, especially bleeding. Sequential TACE and cryosurgery may be the better procedure for unresectable HCC, especially for large HCC.

Chemotherapy： Is it Warranted in Curable Head and Neck Cancer？

Since the last century, many physicians have been trying to utilize chemotherapy to replace conventional surgical treatment for cases of cancer of the oropharynx, larynx, and hypopharynx, which would otherwise be candidates for total laryngectomy. Some authors claim that the preservation rate of the larynx increases after treatment by chemotherapy, which even may take the place of routine surgical methods. However, when calculated in a more rigorous way following accepted statistical methods, what they claim is questionable. As a result, the routine application of chemotherapy in its present form is not advisable for curable squamous cell carcinoma of the head and neck region. Further research is required to justify its benefit.

Expression of a plant-associated human cancer antigen in normal,premalignant and malignant esophageal tissues

AIM: To study the relationship between the expression profiles of a plant-associated human cancer antigen and carcinogenesis of esophagus and its significance. METHODS: We analyzed expression of a plant-associated human cancer antigen in biopsy specimens of normal (n=29),mildly hyperplastic (n=29), mildly (n=30), moderately (n=27)and severely dysplastic (n=29) and malignant esophageal (n=30) tissues by immunohistochemistry. RESULTS: The plant-associated human cancer antigen was mainly confined to the cytoplasm and showed diffuse type of staining. Positive staining was absent or weak in normal (0/30) and mildly hyperplastic tissue samples (2/29), while strong staining was observed in severe dysplasia (23/29) and carcinoma in situ (24/30). There was significant difference of its expression between normal mucosa and severely dysplastic tissues (P＜0.001) or carcinoma in situ (P＜0.001). Significant difference was also observed between mild dysplasia and severe dysplasia (P＜0.001) or carcinomain situ (P＜0.001). An overall trend toward increased staining intensity with increasing grade of dysplasia was found. There was a linear correlation between grade of lesions and staining intensity (r=0.794,P＜0.001). Samples from esophageal cancer showed no higher levels of expression than those in severely dysplastic lesions (P＞0.05). CONCLUSION: The abnormal expression of this plantassociated human cancer antigen in esophageal lesions is a frequent and early finding in the normal-dysplasiacarcinoma sequence in esophageal carcinogenesis. It might contribute to the carcinogenesis of esophageal cancer. The abnormal expression of this plant-associated human cancer antigen in esophageal lesion tissues may serve as a potential new biomarker for early identification of esophageal cancer.

Telomerase activity and human telomerase reverse transcriptase expression in colorectal carcinoma

AIM： To study the activity of telomerase and the expression of human telomerase reverse transcriptase （hTERT） in colorectal carcinoma and its adjacent tissues, normal mucosa and adenomatoid polyp, and to evaluate their relation with carcinogenesis and progression of colorectal carcinoma. METHODS： Telomerase activity and hTERT expression were determined in 30 samples of colorectal carcinoma and its adjacent tissues, normal mucosa and 20 samples of adenomatoid polyp by modified telomeric repeat amplification protocol （TRAP）, enzyme-linked immunosorbent assay （ELISA） and immunohistochemical method. RESULTS： Telomerase activity and hTERT expression were 83.33% （25/30） and 76.67% （23/30） respectively in colorectal carcinoma, which were obviously higher than those in paracancerous tissues （13.33%, 16.67%）, normal mucosa （3.33%, 3.33%） and adenomatoid polyp （10%, 10%）. There was a significant difference between colorectal carcinoma and other tissues （P=0.027）. The telomerase activity and hTERT expression were higher in colorectal carcinoma with lymphatic metastasis than in that without lymphatic metastasis （P=0.034）. When the histological classification and clinical stage were greater, the telomerase activity and hTERT expression increased, but there was no significant difference between them. In colorectal carcinoma, the telomerase activity was correlated with hTERT expression （positive vs negative expression of telomerase activity and hTERT, P=0.021）. CONCLUSION： Telomerase activity is closely correlated with the occurrence, development and metastasis of colorectal carcinoma. Overexpression of hTERT may play a critical role in the regulation of telomerase activity.

The Application of FJI and Its Comparison with Different Alimentary Reconstructions after Total Gastrectomy for Cances

Objective To investigate the optimum reconstruction after total gastrectomy for malignant disease,especially the necessity of gastric substitute and duodenal passage.Methods Among the 459 total gastrectomy cases,6 kinds of reconstructions had been used,including Braun,modified Braun I(mBraun I),modified Braun Ⅱ（mBraun Ⅱ),Roux-en-Y,“P jejunal interposition(PJI)and functional jejunal interposition(FJI).Postoperative complains,body weight,food intake,serum nutritional paraments,complete blood cout,half-emptying time of the gastric substitute,PNI,Visick index were evaluated one year after r surgery.Results As compared with Braun group,the mBraun I,Ⅱ and Roux-en-Y groups which had some kinds of gastric substitute showed less reflux esophagitis and higher serum total protein(P<0.01).As compared with mBraun I,Ⅱ,Roux-en-Y,PJI and FJI groups which had duodenal passage showed better body weight,higher nutritional paraments and PNI(P<0.05).Conclusion It is essential to construct a gastric substitute and maintain the food chyme flowing through the duodenum after total gastrectomy,and the FJI is a better choice in this study.

INHIBITORY EFFECTS OF MIFEPRISTONE ON THE GROWTH OF HUMAN GASTRIC CANCER CELL LINE MKN-45 IN VITRO AND IN VIVO

Objective To explore the effects of mifepristone on the growth of human gastric cancer cell line MKN-45 and its possible mechanisms. Methods In situ hybridization was used to detect the expression of progesterone receptor (PR) mRNA in MKN-45 cells. Proliferation, cell cycle distribution, and the expression of Bcl-xL and vascular endothelial growth factor (VEGF) of MKN-45 cells incubated with various concentrations of mifepristone (1, 5, 10, and 20 μmol/L) were analyzed using MTT reduction assay, flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR), and enzyme-linked immunoab-sorbent assay (ELISA), respectively. After transplantation of MKN-45 cells underneath the skin of athymic mice, mifepristone was administrated with the dose of 50 mg/(kg·d) for 6 weeks to evaluate the tumor growth. Apoptosis and the expression of proliferating cell nuclear antigen (PCNA) in xenografted tumors were detected using transmission electron microscopy and immunohistochemical staining, respectively. Results PR mRNA was highly expressed in cultured MKN-45 cell. Mifepristone dose-dependently inhibited the pr-oliferation of MKN-45 cells, and the inhibitory rate was dramatically increased from 7.21% to 47.23%. The inhibitory effect was accompanied by a dose-dependent increase in the percentage of cells in G 0 /G 1 phase, and with a concurrent decrease in the proportion of S- and G 2 /M-phase cells and the proliferative index from 57.65% to 24.54%. Meanwhile, mifepristone down-regulated the expression of Bcl-xL and VEGF in a dose-dependent manner. In vivo, mifepristone effectively inhibited the growth of xenografted tumors in nude mice (55.14% for inhibitory rate), induced apoptosis, and down-regulated PCNA expression in gastric cancer. Conclusion Mifepristone exerts significant growth inhibitory effects on PR-positive human MKN-45 gastric cancer cells via multiple mechanisms, and may be a beneficial agent against the tumor.

C-kit gene mutation in human gastrointestinal stromal tumors

AIM: TO investigate the significance of c-kit gene mutation in gastrointestinal stromal tumors (GIST).METHODS: Fifty two cases of GIST and 28 cases of other tumors were examined. DNA samples were extracted from paraffin sections and fresh blocks. Exons 11, 9 and 13 of the c-kit gene were amplified by PCR and sequenced.RESULTS: Mutations of exon 11 were found in 14 of 25 malignant GISTs (56%), mutations of exon 11 of the c-kit gene were revealed in 2 of 19 borderline GISTs (10.5%),and no mutation was found in benign tumors. The mutation rate showed significant difference (x^2=14.39, P<0.01) between malignant and benign GISTs. Most of mutations consisted of the in-frame deletion or replication from 3 to 48 bp in heterozygous and homozygous fashions, None of the mutations disrupted the downstream reading frame of the gene. Point mutations and frame deletions were most frequently observed at codons 550-560, but duplications were most concentrated at codons 570-585. No mutations of exons 9 and 13 were revealed in GISTs, Neither c-kit gene expression nor gene mutations were found in 3 leiomyomas, 8 leiomyosarcomas, 2 schwannomas, 2 malignant peripheral nerve sheath tumors, 2 intra-abdominal fibromatoses, 2 malignant fibrous histiocytomas and 9 adenocarcinomas.CONCLUSION: C-kit gene mutations occur preferentially in malignant GISTs and might be a clinically useful adjunct marker in the evaluation of GISTs and can help to differentiate GISTs from other mesenchymal tumors of gastrointestinal tract, such as smooth muscle tumors,schwannomas, etc.

Colorectal neoplasm:Magnetic resonance colonography with fat enema-initial clinical experience

AIM： To assess Magnetic resonance colonography with fat enema as a method for detection of colorectal neoplasm.METHODS： Consecutive twenty-two patients underwent MR colonography with fat enema before colonoscopy. Tl-weighted three-dimensional fast spoiled gradient- echo with inversion recovery sequence was acquired with the patient in the supine position before and 75 s after Gadopentetate Dimelumine administration. Where by, pre and post MR coronal images were obtained with a single breath hold for about 20 s to cover the entire colon. The quality of MR colonographs and patients＇ tolerance to fat contrast medium was investigated. Colorectal neoplasms identified by MR colonography were compared with those identified on colonoscopy and sensitivity of detecting the lesions was calculated accordingly.RESULTS： MR colonography with fat enema was well tolerated without sedation and analgesia. 120 out of 132 （90.9%） colonic segments were well distended and only 1 （0.8%） colonic segment was poor distension. After contrast enhancement scan, mean contrast-to-noise ratio （CNR） value between the normal colonic wall and lumen was 18.5 ± 2.9 while mean CNR value between colorectal neoplasm and lumen was 20.2± 3.1. By Magnetic resonance colonography, 26 of 35 neoplasms （sensitivity 74.3%） were detected. However, sensitivity of MRC was 95.5% （21 of 22） for neoplasm larger than 10 mm and 55.6% （5 of 9） for 5-10 mm neoplasm.CONCLUSION： MR colonography with fat enema and Tl-weighted three-dimensional fast spoiled gradientecho with inversion recovery sequence is feasible in detecting colorectal neoplasm larger than 10 mm.

Three novel missense germline mutations in different exons of MSH6 gene in Chinese hereditary non-polyposis colorectal cancer families

AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4th, 6th and 9th exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.

Inhibition of DNA primase and induction of apoptosis by 3,3'-diethyl-9-methylthia-carbocyanine iodide in hepatocellular carcinoma BEL-7402 cells

AIM:To evaluate the effects of 3,3′-diethyl-9-methylthia-carbocyanine iodide (DMTCCI) on DNA primase activity and on apoptosis of human hepatocellular carcinoma BEL-7402 cells.METHODS: DNA primase assay was used to investigate DNA primase activity. MTT assay was applied to determine cell proliferation. Flow cytometric analysis, transmission electron microscopy, DNA fragmentation assay were performed to detect DMTCCI-induced apoptosis. Expression levels of p53, Bcl-2, Bcl-xL, Bad, Bax, survivin, Caspase-3 and poly (ADP-ribose) polymerase (PARP) were evaluated by immunoblot analysis. Caspase-3 activity was assessed with ApoAlert Caspase-3 colorimetric assay kit.RESULTS:DMTCCI had inhibitory effects on eukaryotic DNA primase activity with IC50 value of 162.2 nmol/L. It also inhibited proliferation of human hepatocellular carcinoma BEL-7402 cells with IC50 value of 2.09μmol/L. Furthermore,DMTCCI-induced BEL-7402 cell apoptosis was confirmed by DNA fragmentation (DNA ladders and sub-G1 formation) and transmission electron microscopy (apoptotic bodies formation). During the induction of apoptosis, expression of Bcl-2, Bcl-xL and survivin was decreased, and that of p53,Bad and Bax was increased. Caspase-3 was activated and poly (ADP-ribose) polymerase (PARP) was cleaved in BEL-7402 cells treated with DMTCCI.CONCLUSION: The present data suggest that DMTCCI has inhibitory effects on eukaryotic DNA primase and can induce apoptosis of BEL-7402 cells. The modulation of expression of p53 and Bcl-2 family proteins, and activation of Caspase-3 might be involved in the induction of apoptosis.

Study of the Clinical Effects of Concomitant Splenectomy an Patients with Hepatocellular Carcinoma Accompanied with Cirrhosis and Hypersplenism

OBJECTIVE To discuss the clinical efects of concomitant splenectomy in hepatocellular carcinoma patients accompanied with cirrhosis and hypersplenismMETHODS Sixty-seven patients who had hepatocellular carcinoma (HCC) accompanied with hypersplenism from December 1999 to March 2002 were reviewed retrospectively. Thirty-eight patients underwent liver and spleen united resection (splenectomy group) and 29 patients received a hepatectomy (non-splenectomy group).One day before operation and 7 days after operation, the concentration of vascular endothelium growth factor (VEGF) in peripheral blood and splenic venous blood were compared between the two groups.RESULTS The increase of PLT and WBC was significantly higher in patients who underwent concomitant splenectomy compared to patients who did not receive a splenectomy (P<0.05). The occurrence of complications was 28.9% (11/38) in the splenectomy group and 20.6% (6/29) in the nonsplenectomy group, and the recurrence rate one year later was 21.1 %(8/38) in the splenectomy group and 20.6%(6/29) in the non-splenectomy group. There was no significant difference in occurrence of complications and recurrence rates between the two groups. The concentration of VEGF was not significantly different between peripheral blood versus splenic venous blood. Twenty-nine patients in the splenectomy group received hepatic arterial chemoembolization 1-3 times successfully after operation, but in the non-splenectomy group there were 7 patients who had to stop receiving the successive treatment because the PLT and WBC were too low.CONCLUSION Combined splenectomy is helpful to raise the PLT and WBC count and enable patients to receive subsequent chemoembolization. Early recurrence and metastases are not significantly different between patients with and without splenectomy.

Local excision carcinoma in early stage

AIM: To assess the validity of local excision for the early stage low rectal cancer as an effective treatment alternative to radical resection.METHODS: A retrospective medical chart review was done in 47 patients with early stage low rectal carcinoma who underwent local excision from November 1980 through November 1999 at Cancer Hospital of Chinese Academy of Medical Sciences (CAMS). The patients were treated by either transanal (40 cases), trans-sacral (5 cases), or trans-vaginal (2 cases) excision of tumors and no death was related to surgery. Sixteen patients received postoperative radiotherapy.RESULTS: T1 and T2 lesion was found in 36 (76.6 %) and 11 patients (23.4 %) respectively. The overall local tumor recurrence rate was 14.9 % (7/47), with an average recurrence time of 21 months. Among these 7 recurrent patients, there were 4 T1 and 3 T2 lesions. Microscopically,the surgical incisal margin was negative in 45 (95.7 %) and positive in 2 patients (4.3 %); Both of the later had developed local recurrence. The overall 5-year survival rate was 91.7 %,in which there were 94.4 % for T1 and 83.3 % for T2 tumors.T stage, intravessel tumor thrombosis, lymphocytic infiltration and histological grade were not found to be significant by related to the local recurrence and survival (P＞0.05).CONCLUSION: Local tumor excision was a safe procedure for the treatment of early stage low rectal carcinoma with minimal morbidity and mortality, which might serves as one of the primary surgical treatment methods for the disease of this kind.

Arsenic Trioxide Induced Differentiation and Apoptosis in Human Nasopharyngeal Carcinoma Xenografts in BALB／C Nude Mice

To study the effect of arsenic trioxide (As2O3) on human poorly differentiated nasopharyngeal cancer cell line, CSNE-1, in vivo and its possible mechanism of action. Methods: CSNE-1 cells were established as xenografts in BALB/C nude mice. The tumor-bearing mice were treated with As2O3 at the dose of 5 mg/kg every day. The tumor growth was observed by tumor-growth curve. Morphologic changes were studied under light microscopy and electron microscopy. TUNEL was used to detect apoptosis. The expression of PCNA, p53, Bcl-2 and Bax were determined by immunohistochemistry. Results: The cell growth and proliferate activity were significantly inhibited by As203 at the dose of 5 mg/kg every day. Morphologic changes such as the formation of keratinization of tumor cells, decreased ratio of nuclear/cytoplasm, increased organelle and plasmic fibril in cytoplasm were identified. Cytodesma, desmosomes and micro-process were seen under light microscopy and transmission electron microscopy, which revealed that the cancer cells underwent differentiation. In addition, remarkable cell apoptosis were observed by TUNEL assay. Over expression of p53 and Bax was detected in the As203 treatment group when compared with control group. Conclusion: As203 inhibited proliferation of human poorly differentiated nasopharyngeal cancer cell CSNE-1 by inducing differentiation and apoptosis, which may be related to the up-regulation of p53 and Bax expression.