A serum-stable branched dimeric anti-VEGF peptide blocks tumor growth via anti-angiogenic activity

Angiogenesis is critical and indispensable for tumor progression. Since VEGF is known to play a central role in angiogenesis, the disruption of VEGF-VEGF receptor system is a promising target for anti-cancer therapy. Previously, we reported that a hexapeptide (RRKRRR, RK6) blocked the growth and metastasis of tumor by inhibiting VEGF binding to its receptors. In addition, dRK6, the D-form derivative of RK6, retained its biological activity with improved serum stability. In the present study, we developed a serum-stable branched dimeric peptide (MAP2-dRK6) with enhanced anti-VEGF and anti-tumor activity. MAP2-dRK6 is more effective than dRK6 in many respects: inhibition of VEGF binding to its receptors, VEGF- and tumor conditioned medium-induced proliferation and ERK signaling of endothelial cells, and VEGF-induced migration and tube formation of endothelial cells. Moreover, MAP2-dRK6 blocks in vivo growth of VEGF-secreting colorectal cancer cells by the suppression of angiogenesis and the subsequent induction of tumor cell apoptosis. Our observations suggest that MAP2-dRK6 can be a prospective therapeutic molecule or lead compound for the development of drugs for various VEGF-related angiogenic diseases.

Comparison of the Efficacy of Oral Capecitabine versus Bolus 5-FU in Preoperative Radiotherapy of Locally Advanced Rectal Cancer

The effects of treatment with oral capecitabine vs. bolus 5-FU, administered concurrently with preoperative radiotherapy, were compared in the treatment of locally advanced rectal cancer (LARC). One hundred and twenty-seven patients with LARC received concurrent preoperative chemoradiation using two cycles bolus 5-FU (500 mg/m2/day) plus leucovorin (LV, 20 mg/m2/day) (Group I). Another LARC group received concurrent chemoradiation using two cycles 1,650 mg/m2/day of oral capecitabine and 20 mg/m2/day of LV (Group II, 97 patients). Radiation was delivered to the primary tumor at 50.4 Gy in both groups. Definitive surgery was performed 6 weeks after the completion of chemoradiation. A pathologic complete remission was achieved in 11.4% of patients in Group I and in 22.2% of patients in Group II (p= 0.042). The down-staging rates of the primary tumor and lymph nodes were 39.0/ 68.7% in Group I and 61.1/87.5% in Group II (p=0.002/0.005). Sphincter-preserving surgery was possible in 42.1% of patients in Group I and 66.7% of those in Group II (p=0.021). Grade 3 or 4 leucopenia, diarrhea, and radiation dermatitis were statistically more prevalent in Group I than in Group II, while the opposite was true for grade 3 hand-foot syndrome. Preoperative chemoradiation using oral capecitabine was better tolerated than bolus 5-FU and was more effective in the promotion of both down-staging and sphincter preservation in patients with LARC.

Effect of Ionizing Radiation on Homotypic Cell Adhesion, Cell-Matrix Adhesion, Matrix Metalloproteinases Excretion of High Mucin Producing HM7 Colon Cancer Cells

PURPOSE: To investigate the effect of ionizing radiation on high mucin-producing colon cancer cells, we evaluated homotypic cell adhesion, cell-matrix adhesion, and matrix metalloproteinases (MMPs) on HM7 cells. METHODS: After an irradiation of 60 Gy for 48 hours on HM7 cells, we evaluated cellular proliferation, colony-forming ability, homotypic adhesion, cell-matrix binding, and integrin subunit expressions. Also, alterations of MMPs expression were analyzed by using zymography. RESULTS: Cell proliferation of HM7 colon cancer cells was not remarkably affected even after high doses of radiation; however, clonogenic cell growth was significantly affected. Homotypic cell-cell adhesion and cell adhesion to ECM components and basement membrane protein matrigel were significantly increased after irradiation. Radiation induced expressions of cell surface integrin alpha2, alpha3, and beta1 subunits of HM7 cells. The activities of secreted MMPs (MMP-9 and MMP-2) were remarkably inhibited by radiation. CONCLUSIONS: These finding suggest the biologic characteristics of high-mucin-producing colorectal carcinomas. Even though the radiation-associated cellular alterations of HM7 cells with or without matrix proteins were not remarkably different from other cancer cell types studied, the radio-resistant behavior of high mucin producing HM7 cells may explain the aggressive characteristics of mucinous colorectal carcinomas.

Treatment of Chronic Anal Fissure with Topical Nitroglycerin

PURPOSE: Lateral partial internal sphincterotomy is considered as the best surgical procedure of the idiopathic chronic anal fissure. Because the aim of surgery is to relieve sphincter spasm, and occasional minor incontinence following surgery has been reported, alternative chemical means of spasmolysis could be considered. Nitric oxide (NO) is known to be a major inhibitory neurotransmitter of the internal anal sphincter, so we investigated the effect of topical nitroglycerin for chronic anal fissure. METHODS: Twenty nine patients (19 women, mean age 36 years) with chronic anal fissure were treated with 0.2% nitroglycerin ointment. Pain score was quantitated with Visual Analog Scale (VAS) in regular time interval. Manometry was performed in five patients and maximum anal resting pressure (MARP) was measured before and 30 minutes after topical application of nitroglycerin ointment. All patients were re-examined and questioned regarding pain relief and side effects 2 years after cessation of treatment. RESULTS: All had appearances of chronicity and pain. There were 25 posterior and 12 anterior fissures. Pain was significantly abolished within 5 minutes after application of nitroglycerin ointment. Mean pain score (VAS) was 6.03 before, 0.69 30 min after, 0.58 1 week after, and 0.53 3 weeks after application of nitroglycerin ointment (P<0.001). MARP was markedly reduced 30 minutes after application of nitroglycerin from 166.2 15.1 cmH2O to 108.8 20.9 cmH2O (P<0.05). The 57% of patients (13/23) were effective for 2 years and 22% of patients (5/23) had recurred their symptom after cessation of nitroglycerin ointment. Two patients (9%), whose fissures had not healed completely within 3 weeks were requested for surgery and the other 2 patients (9%) had been operate due to the side effect of the ointment. Mild headache (7%) and dizziness (10%) were occured, but well tolerated when the dose was reduced. CONCLUSIONS: Topical application of nitroglycerin ointment seems to be an effective and safe alternative in the treatment of chronic anal fissure.

Papillary Serous Carcinoma in Rectum-a Case of Complete Remission of Bulky Pelvic Disease after Platinum-paclitaxel Combination Chemotherapy

Papillary serous carcinoma of the peritoneum (PSCP) is a primary tumor of peritoneal lining (mesothelioma) of the abdomen and is histologically difficult to differentiate from papillary serous carcinoma of the ovary. It is very rare tumor that involves the surface of the pelvic and/or abdominal peritoneum. Most patients with this tumor have been treated with optimally surgical cytoreduction and postoperative chemotherapy. However, long term survival has not been achieved in many studies. In recent years, platinum-paclitaxel combination therapy was reported as a effective initial therapy for recurrent PSCP. We have experienced one case of recurrent PSCP which was successfully treated with heptaplatin and paclitaxel. We report the toxicity and long term result of the patient.

The Causes and Clinical Significance of Hyperamylasemia Following Colorectal Surgery

PURPOSE: Postoperative hyperamylasemia and pancreatitis may sometimes follow abdominal surgery but the significance and cause of hyperamylasemia after colorectal surgery were not studied enoughly. Our study was designed to identify the incidence of hyperamylasemia after colorectal surgery, to investigate the effect of hyperamylasemia on postoperative hospital course, and to clarify the causes such as extent of colorectal resection or intraoperative events. METHODS: The serum amylase was determined in post operative first day in random sampled 72 patient among whom underwent elective colorectal resection from March 2000 to July 2001. If a hyperamylasemia was evident, repeated check the level till it returned to within normal range. Other factors that seemed to affect serum amylase such as traction of pancreas during operative manupulation, intraoperative hypotensive episode or infused drug and volume expanders etc. were reviewed and analysed. RESULTS: Hyperamylasemia occurred in 25 patients (34.7%) after colorectal surgery. Serum amylse level returned to normal in all but nine patients (12.4%) by third postoperative day, two patients (2.8%) by the fifth postoperative day. Pancreas manupulation and intraoperative use of volume expander, amylopectin were found to be significantly associated with postoperative hyperamylasemia by 2-test and pearson correlation analysis. The developement of hyperamylasemia did not adversely influence the postoperative hospital course. CONCLUSIONS: Twenty-five (34.7%) in seventy-two patients who underwent colorectal surgery developed hyperamylasemia after operation. The incidence was significantly high in a group who underwent surgical procedure with more pancreas manupulation and infused hydroxyethyl starch (amylopectin) containing volume expander. The development of postoperative hyperamylasemia did not seem to influence adversely the postoperative hospital course in this study.

Surgically Correctable Fecal Incontinence Associated with Traumatic Duhamel Operation: A Report of Three Cases

We present 3 cases of fecal incontinence associated with traumatic injury during Duhamel procedure. Three male patients suffered from persistent fecal soiling and incontinence for more than 7 years after definitive surgery for Hirschsprung's disease by a pediatric surgeon. They showed grade 4 frequent major soiling, mild patulous anus, and flattening of the anorectal angle due to traumatic injury of the external sphincter and puborectalis muscle on the posterior midline of the anorectal junction. On Parks postanal pelvic floor repair procedures, the incontinent symptoms were abated, anatomic changes were normalized, and postoperative Kirwan classification scales were markedly improved from grade 4 to grade 1. Patients with fecal incontinence after Duhamel operation for Hirschsprung's disease may have a traumatic injury of the anal sphincter. Careful physical and laboratory examinations should be performed for the confirmation of traumatic injury in these patients, and Parks postanal repair could be the treatment of choice for the correction of incontinence.

Epidermal Growth Factor Dependent Expression of Plasminogen Activator and Plasminogen Activator Inhibitor in Rat Hepatocytes in Primary Culture

PURPOSE: In order to clarify the the role of epidermal growth factor (EGF) in the regulation of plasminogen activator (PA) and plasminogen activator inhibitor (PAI) during liver regeneration, we investigated the EGF-dependent gene expression of PA and PAI-1 in rat hepatocytes in primary culture. METHODS: Hepatocytes were isolated from rats using a two step perfusion technique and cultivated in dishes precoated with rat tail collagen. DNA synthesis of the hepatocytes by EGF treatment was measured with (3)H-thymidine incorporation. Gene expression for PAI-1, uPA and tPA was examined using Northern blot hybridization analysis. RESULTS: EGF treatment increased the (3)H-thymidine incorporation of the hepatocytes up to 36 hours and normal polygonal hepatocyte morphology was achieved simultaneously. tPA and PAI-1 mRNA were detected in the control hepatocytes. With the EGF treatment, the tPA mRNA level increased with time up to 48 hours, however the PAI-1 mRNA level rapidly increased to 1 hour and then decreased quickly to the control level. On the contrary, uPA mRNA was not detected in hepatocytes with or without treatment of EGF. The EGF-dependent induction of tPA and PAI-1 mRNA was a protein synthesis independent process. CONCLUSION: These results suggest that differential expression of tPA and PAI-1 mRNA by EGF in hepatocytes may play an important role in the regulation of liver regeneration. Among PAs, tPA seemed to be more important in EGF dependent growth or regeneration of primary hepatocytes in the rat since uPA mRNA was not induced in primary hepatocyte cultures in spite of EGF treatment.

Conservative Chemoradiation Treatment for Epidermoid Carcinoma of the Anal Canal

PURPOSE: Anal canal carcinoma is a rare clinical entity accounting for 1 to 3 percent of all gastrointestinal malignancies. Prevoiously, abdominoperineal resection was the primary modality of treatment. However, a recurrence rate of 20 to 40 percent has been observed following this procedure. In recent years, multimodal therapy with radiation and chemotherapy has been shown to at least equal the results obtained through surgery with the ability to preserve sphincter function. The objective of this study is to evaluate the survival, recurrence pattern, acute and late morbidity rates of a widely used combined chemotherapy and radiation therapy regimen given to patients with carcinoma of the anal canal. METHODS: Ten patients received radiation therapy (5,000~5,400 cGy) and chemotherapy (mitomycin-C plus 5-fluorouracil) as a primary treatment between 1988 and 1998. RESULTS: Patients with primary tumors had a complete response rate of 60 percent and a 10-year corrected survival rate and disease-free survival rate of 77.14 percent and 60 percent, respectively. There was a significant difference in survival rates and disease-free survival rates according to AJCC stage. Acute complications (grade III~IV, ECOG toxicity criteria) such as leukopenia, anemia, thrombocytopenia and radiation dermatitis were seen in 10 to 50 percent of cases. Furthermore, 20 percent of patients experienced late treatment-related symptoms including perineal fibrosis and incontinence due to sphincter dysfunction. CONCLUSION: The current treatment regimen is effective but carries a considerable risk of complications. Therefore, new chemotherapeutic modalities that may reduce such complications, but still potent, are needed.

Neuroendocrine Neoplasm of the Colon and Rectum

PURPOSE: This report outlines the incidence and the clinical features of patients with a neuroendocrine (NE) neoplasm of the colon and rectum and describes, in detail, their histologic and immunohistochemical findings. Also, we attempted to determine the impact of several clinical variables, including tumor stage, tumor location, NE pattern, and cellular subtype on survival. METHOD: Of 690 colorectal cancers operated on from April 1990 to November 1998 at Chungnam National University Hospital, 41 cases were originally diagnosed as poorly differentiated adenocarcinoms on the basis of conventional light microscopy. Paraffin blocks from the aforementioned cases were retrieved, and sections were im munostained with antibodies to human chromogranin A, neuron specific enolase, and synaptophysin. RESULTS: Of the 690 cases of colorectal caner, 35 cases (5.1%) of NE neoplasm were identified retrospectively: 28 males and 7 females. About 90% of the tumors were located at the cecum and the rectosigmoid. Pathologic stages were as follows: modified Dukes stage B2, 6; stage C1, 8; stage D1, 12; and stage D2, 9. The most common metastatic site at the time of diagnosis was the liver (8/9). Four NE patterns were identified: pure NE (n=4), and predominantly NE (n=8), equal NE and exocrine (n=4), and predominantly exocrine (n=19). Two cellular subtypes were identified: well-differentiated (n=3) and intermediate (n=32) cells. Survival statistically correlated with stage (p=0.03), but not with age, sex, tumor location, NE pattern, or cellular subtype. CONCLUSION: This study suggests that NE neoplasms of the colon and rectum are more frequent than previously believed. Since a NE neoplasm is believed to be an extremely biologically aggressive tumor, recognition of a NE neoplasm is very important because of its evident clinical and therapeutic implications.

Transcriptional Regulation of H2B Histone Gene Expression by Nocodazole in HL-60 Cells / 대한암학회지

PURPOSE: Nocodazole, a microtubule disrupting reagent, is known to arrest cells in the M phase, To gain insight on the regulatory mechanism of H2B histone gene expression by nocodazole in HL-60 cell, the binding pattern of nuclear proteins to cis element in the human H2B histone gene promoter has been investigated with DNase I footprinting and DNA mobility shift assay. MATERIALS AND METHODS: Northern blot hybridization was performed by the method of Virca et al. A Hinc II-Sac I fragment of pSPH28 was used as probe for Northern blot analysis of H2B histone mRNA. DNase I footprinting and DNA mobility shift assay were performed by the method of Lim et al. End labeled DNA oligomer (upper strand, 5'-CTTCACCTTATTTGCATAA GCGATTC-3') for octamer binding activity was mixed with nuclear extracts in a 20 ul reaction volume containing 60 mM KC1, 12 mM HEPES, pH 7.9, 5 mM MgCl2, 0.2 mM EDTA, 0.2 mM DTT, 12% glycerol, and 2 ug of poly [dI-dC]. RESULTS: The level of H2B histone mRNA rapidly was reduced at 24 hours in nocodazole-treated HL-60 cells and the mRNA was repressed in proportion to the concentration of nocodazole. Nocodazole-dependent repression of H2B histone gene was restored by replacement with nocodazole-free media. In DNase I footprinting analysis, one nuclear factor bound at 42 bp site (octamer motif) in the absence of nocodazole. In the presence of nocodazole, the binding of nuclear factor on octamer motif partially vanished. In DNA mobility shift assay, one DNA-protein complex (Octl) was formed when octamer motif was incubated with nuclear extract of HL-60 cell. After nocodazole treatment, Octl binding activity was reduced by time dependent manner. CONCLUSION: These results suggest that nocodazole-dependent repression of H2B histone gene is correlated with reduction of Octl binding activity in HL-60 cell.

The Treatment Results of Preoperative Concurrent Chemoradiation in Locally Advanced Rectal Cancer / 대한암학회지

PURPOSE: To assess the tumor response, sphincter preservation, acute toxicity and survival with preoperative concurrent chemoradiation in locally advanced rectal cancer. MATERIALS AND METHODS: Fifty-four patients were treated with preoperative chemoradiaton for tumor downstaging and sphincter preservation. Radiation was delivered to whole pelvis to 45 Gy followed by a boost 5.4 Gy to primary tumor site. Chemotherapy consists of concurrent 2 cycles of 5-fluorouracil (500 mg/m2/day) and leucovorin (20 mg/m2/day). Surgery was performed approximately 6 weeks after treatment. RESULTS: Median follow-up period and rate were 48 months and 98%, respectively. The downstaging including primary tumor and lymph node occurred in 64%. Three of 53 patients (6%) had pathologic complete response. The resectability of tumor was 98%. A sphincter preservation was possible in 61%. Three patients developed grade 4 hematologic toxicity. Grade 3 skin erythema and diarrhea were 24% and 18%, respectively. The 5-year survival and local disease-free survival were 62% and 89%, respectively. Local failure and distant metastasis rate were 9% and 35%, respectively. CONCLUSION: Preoperative chemoradiation affords considerable downstaging with acceptable acute toxicity and postoperative morbidity. Also sphincter preservation is feasible by improved downstaging of tumor. This treatment could be improved local control of tumor, and may have a potential for long-term survival.

Role of ATF on Transcriptional Regulation of DNA Topoisomerase II a Gene in HL - 60 Arrested to G2 / M and M Phase / 대한암학회지

PURPOSE: To gain insight on transcriptional repression of Topo II a in HL-60 cells arrested to G2/M and M phase, the levels of Topo IIa mRNA and the binding activity of ATF have been investigated with Northern blot hybridization and DNA mobility shift assay, respectively. MATERIALS AND METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-mactivated fetal bovine serum and antibiotics in a humidified 5% CO2 at 37C degree. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. A Xho I-Mlu I fragment of phTOP2 was used as probe for Northern blot analysis of Topo II a mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA oligomer (upper strand, 5-TCTCCGCTATGACGCCGAGTGGTG-3) for ATF binding activity was mixed with nuclear extracts in a 20 pl reaction volume containing 60 mM KC1, 12 mM HEPES, pH 7.9, 5 mM MgCl2, 0.2 mM EDTA, 0.2 mM DTT, 12% glycerol, and 2 ug of poly [dI-dC]. RESULTS: HL-60 cells were arrested at G2/M phase and M phase after taxol or nocodazole treatment. The levels of Topo II a mRNA were reduced at 24 hours after exposure with nocodazole or taxol but the unknotting activities were not changed. DNA mobility shift assay using oligonucleotide containing the ATF binding site showed that ATF binding activity was reduced after pretreatment of nododazole or taxol. CONCLUSIONS: These results suggest that the reduction of ATF binding activity may be important to transcriptional repression of Topo II a gene by nocodazole and taxol in HL- 60 cells.

Isolation and Characterization of Tumor Cell - Derived Immunoregulatory Factors / 대한면역학회지

It has been known that the immunological functions against cancer cells were diminished, and these phenomena result from the inhibition of cell-mediated immunity by substance(s) secreted from cancer cells. It was also reported that the immunological functions decreased in patients with stomach cancer, which is the most frequent cnacer in Korean. However, the nature and function of the inhibitory factor(s) orignated from stomach cancer have not been identified. To elucidate effects of immuological inhibitory factor(s) secreted from cancer cells, SNU-1 (stomach cancer) and SW480 P109/R3P2 (colon cancer) were used in this study. Jurkat T cell line, an acute T cell leukemia, was pre-incubated with fractionated cancer cell culture supernatant for 3 days, then was stimulated with PMA, PWVanti-CD28 mAb or PMA/ionomycin for 8 hrs respectively. Fraction of SNU-1 (3 - 10 kDa) and above 10 kDa of SW480 P109/R3P2 inhibited the expression of IFN-r mRNA when Jurkat T cell was stimulated with PMA. However, there were no difference in IL-2 and IL-4 gene expression response to either PMA/anti-CD28 mAb or PMA/ionomycin. These results show that cancer cells secret some inhibitory factor(s) acting on the immune response, especially IFN-r gene expression of the Jurkat T cells response to PMA. Therefore, it suggests that the inhibitory factor(s) secreted from cancer cells influences on. the PKC-dependent pathway related to the signal transduction by PMA.

Role of AP-1 Transcriptional Regulation of Vimentin Gene during 12-O-Tetradecanoylphorbol-13-Acetate Differentiation of HL-60 Cells / 대한암학회지

PURPOSE: To gain insight on the role of AP-1 in transcriptional regulation of vimentin gene during differentiation of HL-60 cells by 12-0-tetradecanoylphorbol-13-acetate (TPA), the levels of vimentin mRNA and AP-1 have been investigated with Northern blot hybridization and DNA mobility shift assay. MATERIALS AND METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-inactivated fetal calf serum and antibiotics in a humidified 5% CO2 at 37 degree C. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. EcoRI fragment of pVIM-GEM was used as probe for vimentin mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA probe(Upper strand, 5'-CGCTTGATGAGTCAGCCG- 3') for AP-1 binding activity was mixed with nuclear extracts in a 20 microliter reaction volume containing 300 mM KC1, 60 mM HEPES, pH 7.9, 25 mM MgCl2, 1 mM EDTA, 1 mM DTT, 60% glycerol, and 2 microgram of poly[dI-dC]. RESULTS: TPA increased vimentin mRNA levels, with maxima1 stimulation reached at 24 hr. The level of vimentin mRNA was induced in proportion to the concentration of TPA. TPA-induced vimentin mRNA was almost reduced by actinomycin-D pretreatment. TPA- induced stimulation of vimentin gene was completely reduced by staurosporin pretreatment. In DNA mobility shift assay, AP-I newly appeared at 24 hr during TPA- induced differentiation and was almost not detected after the pretreatment of staurosporin. CONCLUSIONS: These results suggest that the induction of vimentin mRNA during TPA- dependent differentiation in HL-60 cells may be mediated by protein kinases C signal transduction and AP-1 is important to transcriptional regulation.

A Comparative Analysis of the Preoperative Chemoradiation Versus Radiation only for Mid and Lower Rectal Cancer

This study was designed to evaluate the worth of preoperative chemoradiation therapy in the management of locally advanced rectal cancer. Between march 1993 and January 1997, 64 patients with adenocarcinoma of the rectum were treated with preoperative irradiation followed by operation by one surgeon at department of surgery, Chungnam national university hospital. Cancers were treated with high-dose radiation (45 to 54 Gy) with (group 2) or without (group 1) chemotherapy Preoperatively 64 Patients were analysed prospectively, of these, 15 cases were preoperative radiotherapy alone arm and 49 cases were preoperative radiotherapy plus chemotherapy arm. The average age of the patients were 56 years (range 38~67) in group 1 and 57 years (range 27~80) in group 2. Male to female ratio was 8 : 7 in group 1 and 30 : 19 in group 2. Most clinical stage of the primary tumor mass were 73 (80% in Group 1,96% in group 2), being palpated slightly fixed (40% in group 1, 43% in group 2) or fixed (13.3% in group 1, 24.5% in group 2). As to distance of tumor from anal verge, most patients ranged from 4 to 8 cm (53% in group 1, 63.3% in Group 2). Chemotherapy consisted of 2 cycles of 5-fluorouracil (500 mg/m2/day for S days) delivered as a continuous infusion or bolus therapy and low-dose leukovorin (20 mg/m2/day for 5 days). After six weeks resting period of radiation, definitive surgical approach was performed. Overall treatment related toxicity rate was similar in both group except erythema on perineal skin, which was more frequent in group 2 than in group 1. Most frequent postoperative complication was intestinal obstruction (7.8%) followed by wound infection (6.3%), but there was no significant difference between two groups. There was one case of postoperative mortality in group 2 patients at 44 days after operation due to pneumonia and sepsis combined with liver cirrhosis. Tumor depth was downstaged in 38.5% of group 1 and 70% of group 2 patients on preoperative CT staging, and nodal downstaging was more effective on the respect of postoperative pathological report. Overall recurrence rate was 38.5% in group 1 and 20.5% in group 2. Of these, failure occured first as a distant metastasis more frequently than as a local recurrence in both group. These data do suggest that the preoperative chemotherapy and radiotherapy used are as safe as preoperative radiotherapy alone. Futhermore, tumor and lymph node downstaging are more effective in combined arm. Preoperative chemotherapy will more promising in prevention of distant metastasis when treated in the period of least metastatic tumor burden. Whether combined arm will have greater or lesser survival awaits the completion of this relevant study.

Transcriptional REpression of Vimentin Gene During All-TTrans Retinoic Acid-Induced Differentiation of HL-60 Cells / 대한내분비학회지

BACKGROUND: Vimentin is the major intermediate-size filament in the cytoplasm of cells from mesenchymal origin. The HL-60 cell is a unique human leukemic cell line capable of terminal differentiation with several chemical inducers, and then the cell line becomes a fre#quently described model system for cell differentiation in vitro. Vimentin mRNA is reduced during all-trans retinoic acid (retinoic acid) -dependent differentication but increased by 12-0-tetradecanoylphorbol-13-acetate (TPA). In this paper, we have investigated on the mechanism of transcriptional repression of vimentin gene during retinoic acid-dependent differentication of HL-60 cell. METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-inactivated fetal bovine serum and antibiotics in a humidified 5% CO at 37C. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. EcoRI fragment of pVIM-GEM was used as probe for vimentin mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA probe (Upper strand, 5-CGCITGATGAGTCAGCCG-3) for AP-1 binding activity was mixed with nuclear extracts in a 20 pL reaction volume containing 300 mM KCI, 60 mM HEPES, pH 7.9, 25mM MgC1, 1mM EDTA, 1mM DTT, 60% glycerol, and 2 pg of poly[dI-dC]. RESULTS: The level of vimentin mRNA was decreased at 12 hours after retinoic acid treatment, and not detected at 48 hours. The level of vimentin mRNA was reduced in proportion to concentration of retinoic acid, Retinoic acid-reduced vimentin mRNA was no change in cells treated with cycloheximide. Retinoic acid-dependent decrease of vimentin mRNA was partially recovered by staurosporin pretreatment. In DNA mobility shift assay, AP-1 binding activity was reduced at 48 hr during retinoic acid-induced differentiation. CONCLUSION: These results suggest that the transcriptional repression of vimentin gene during retinoic acid-induced differentiation in HL-60 cells is correlated with reduction of DNA binding activity of AP-1.

Role of Cell Surface Mucin on Invasion and Metastasis of HM7 Colon Cancer Cells / 대한암학회지

PURPOSE: Mucinous colorectal cancers have a poorer prognosis than which colorectal cancer produce low amount of mucin, but the exact mechanism is not well understood. The present study was undertaken to elucidate the exact mechanism of invasion and metastasis of high mucin producing colon cancer cells using mucin glycosylation inhibitor, benzyl-alpha-N-acetylgalactosamine. MATERIALS AND METHODS: To evaluate the effect of glycosylated mucin on invasion and metastasis, in vitro invasion, metalloproteinases (MMPs) activity, cell-matrix protein binding, cell-cell aggregation, as well as endothelial leukocyte adhesion molecule (ELAM-1) binding and cell surface expression of various mucin related antigens were analyzed. RESULTS: MMPs activity in conditioned medium and invasion of ECM-coated porous filters by benzyl-alpha-GalNAc treated HM7 cells were decreased. There was no difference between control and treated HM7 cells in terms of matrix protein binding assay, but treated HM7 cells showed higher homotypic cell adhesion. The binding activity of treated HM7 cells to ELAM-1 was significantly decreased and fixed cell binding of MoAb SNH-3, 19-9 (specific for sialyl-Lewis X and sialyl-Lewis A) were also significantly decreased. CONCLUSION: These results suggest that glycosylated mucin modulates ELAM-1 binding, MMPs activity and homotypic cell adhesion, therefore enhance invasive and metastatic properties of human colon cancer cells.

Primary Resection and Anastomosis of Obstructing Carcinoma of the Left Colon

Differential surgical procedures have been described on the treatment of patients with obstructing carcinoma of the left colon and rectum, and these vary from classical three stage approach to primary resection and anastomosis using intraoperative colonic irrigation or subtotal colectomy. Staged colonic prcedures are associated with significant morbidity and mortality eventhough its initial easy performance, and many patients, unfit for further surgery, are left with a permanent colostomy. We have already reported the initial results of intraoperative antegrade colonic irrigation for one-stage operation in obstructing left colorectal cancers. In this investigation, we evaluated the results of prospective trials of primary resection and anastomosis using intraoperative colon irrigation and subtotal colectomy in obstructing left colon and rectal carcinomas. During recent five years, 19 cases of obstructing left colon and rectal carcinomas which could not received regular colon preparation due to marked abdominal distension were enrolled to this study. There were 12 men and 7 women, and mean age was 61. 14 of the 19 patients which tumors located below mid-descending colon were subjected to primary resection and anastomosis using intraoperative antegrade colonic irrigation, 4 patients which tumors located above the mid-descending colon were treated with subtotal colectomy, and remaining one patient which tumor located upper rectum was performed subtotal coloectomy because of underlying colonic ischemia. There was no mortality and significant postoperative complications such as anastomotic lealrage, pelvic abscess or intraabdominal sepsis which seemed to be related with anastomotic dehiscence. Therefore, primary resection and anastomosis using intraoperative colonic irrigation or subtotal colectomy depending on tumor locations in cases of obstructing left colon and rectal carcinomas might be useful methods to obtain safe one-stage restorative colorectal resections.

Treatment Results of Preoperative Radiotherapy Alone vs. Preoperative Radiotherapy and Chemotherapy in Locally Advanced Rectal Cancer / 대한치료방사선과학회지

PURPOSE: To assess the efficacy and toxicity of the preoperative radiotherapy with or without chemotherapy in locally advanced rectal cancer. METHODS: Forty three Patients (clinically diagnosed stages above or equal to Astler-Coller stage B2 without distant metastasis) were assigned to preoperative radiotherapy alone arm (n=16) or combined preoperative radiotherapy and chemotherapy arm (n=27). Preoperative radiotherapy of 4500 cGy to whole pelvis +/- 540 cGy boost to primary site and concurrent chemotherapy of 2 cycles of 5-FU (500 mg/m2) and leucovorin (20 mg/m2) were used. Fifteen patients of preoperative radiotherapy alone arm and 19 of combined arm received surgical resection after preoperative treatment. RESULTS: During the preoperative treatment, no significant complication was developed in both groups. Pathologic results were as follows; complete remission 1, B1 1, B2 6, C1 2, C2 5 in preoperative radiotherapy alone arm and complete remission 2, B1 8, B2 4, C2 3 D2 in combined arm. Postoperative complications were delayed perineal would healing in three patients, intestinal obstruction in three patients (one managed by conservative medical treatment, two by surgical treatment). CONCLUSION: The combined preoperative radiotherapy and chemotherapy arm was more effective in pathological response and lymph node negativity rate that the preoperative radiotherapy alone arm. Both the preoperative radiotherapy alone arm and the combined arm were generally well tolerated and did not result in an increased postoperative morbidity.