Auraptene Has Antiviral Activity against Human Coronavirus OC43 in MRC-5 Cells

Auraptene (7-geranyloxycoumarin) is the abundant prenyloxycoumarin found in the fruits of Citrus spp. Auraptene has a variety of pharmacological and therapeutic functions, such as anticancer, antioxidant, immunomodulatory, and anti-inflammation activities, with excellent safety profiles. In this study, we evaluated the anticoronaviral activity of auraptene in HCoV-OC43-infected human lung fibroblast MRC-5 cells. We found that auraptene effectively inhibited HCoV-OC43-induced cytopathic effects with 4.3 μM IC₅₀ and 6.1 μM IC₉₀, resulting in a selectivity index (CC₅₀/IC₅₀) of >3.5. Auraptene treatment also decreased viral RNA levels in HCoV-OC43-infected cells, as detected through quantitative real-time PCR, and decreased the expression level of spike proteins and nucleocapsid proteins in virus-infected cells, as detected through the Western blot analysis and immunofluorescence staining. Time-of-addition analysis showed auraptene's inhibitory effects at the post-entry stage of the virus life cycle; however, auraptene did not induce the antiviral interferon families, IFN-α1, IFN-β1, and IFN-λ1. Additionally, auraptene-treated MRC-5 cells during HCoV-OC43 infection decreased the MMP-9 mRNA levels which are usually increased due to the infection, as auraptene is a previously reported MMP-9 inhibitor. Therefore, auraptene showed antiviral activity against HCoV-OC43 infection, and we suggest that auraptene has the potential to serve as a therapeutic agent against human coronavirus.

Natural Polyphenols, 1,2,3,4,6-O-Pentagalloyglucose and Proanthocyanidins, as Broad-Spectrum Anticoronaviral Inhibitors Targeting Mpro and RdRp of SARS-CoV-2

The natural plant dietary polyphenols 1,2,3,4,6-O-Pentagalloylglucose (PGG) and proanthocyanidin (PAC) have potent antioxidant activity and a variety of pharmacological activities, including antiviral activity. In this study, we examined the inhibitory effect of PGG and PAC on SARS-CoV-2 virus infection, and elucidated its mode of action. PGG and PAC have dose-dependent inhibitory activity against SARS-CoV-2 infection in Vero cells. PGG has a lower IC₅₀ (15.02 ± 0.75 μM) than PAC (25.90 ± 0.81 μM), suggesting that PGG has better inhibitory activity against SARS-CoV-2 than PAC. The PGG and PAC inhibit similar Mpro activities in a protease activity assay, with IC₅₀ values of 25–26 μM. The effects of PGG and PAC on the activity of the other essential SARS-CoV-2 viral protein, RdRp, were analyzed using a cell-based activity assay system. The activity of RdRp is inhibited by PGG and PAC, and PGG has a lower IC₅₀ (5.098 ± 1.089 μM) than PAC (21.022 ± 1.202 μM), which is consistent with their inhibitory capacity of SARS-CoV-2 infection. PGG and PAC also inhibit infection by SARS-CoV and MERS-CoV. These data indicate that PGG and PAC may be candidate broad-spectrum anticoronaviral therapeutic agents, simultaneously targeting the Mpro and RdRp proteins of SARS-CoV-2.

Bavachin produces immunoadjuvant activity by targeting the NFAT signaling pathway

BACKGROUND

Bavachin, a flavonoid compound isolated from the seeds and fruits of Psoralea corylifolia l. (family Fabaceae), is used as a traditional medicine in Asia. Indeed, it is reported to have various medicinal functions such as estrogenic and antiinflammatory activities among others. However, to date, the effects of bavachin on T cell activation have yet to be reported.

PURPOSE AND STUDY DESIGN

We aimed to determine the effects of bavachin on the activation of a human T cell line in vitro and on antigen-specific immune responses in mice in vivo.

METHODS

In a nuclear factor of activated T cells (NFAT) activity assay, the Jurkat T cell line expressing a luciferase reporter driven by an NFAT-response element was stimulated with antihuman CD3/CD28 antibody and bavachin. Furthermore, the level of cytokine production was measured in the Jurkat T cell line stimulated with phorbol 12-myristate 13-acetate/ionomycin and bavachin using an IL-2 ELISA and a cytometric bead array assay. For in vivo analyses, mice were subcutaneously immunized with an antigen (ovalbumin protein) and bavachin, and the immune responses of mice were analyzed by FACS analysis, a T cell proliferation assay, a cytokine ELISA, and an antiovalbumin-specific antibody ELISA.

RESULTS

We found that bavachin activated NFAT-mediated transcription in the human T cell line in vitro. In mice, when bavachin was administered with the antigen, an increase in T cell responses and antibody production specific to the antigen was observed.

CONCLUSION

Our results suggest that bavachin has immunoadjuvant and immunomodulation effects, which arise through activation of the NFAT signaling pathway.

Lycorine, a non-nucleoside RNA dependent RNA polymerase inhibitor, as potential treatment for emerging coronavirus infections

BACKGROUND

Highly effective novel treatments need to be developed to suppress emerging coronavirus (CoV) infections such as COVID-19. The RNA dependent RNA polymerase (RdRp) among the viral proteins is known as an effective antiviral target. Lycorine is a phenanthridine Amaryllidaceae alkaloid isolated from the bulbs of Lycoris radiata (L'Hér.) Herb. and has various pharmacological bioactivities including antiviral function.

PURPOSE

We investigated the direct-inhibiting action of lycorine on CoV's RdRp, as potential treatment for emerging CoV infections.

METHODS

We examined the inhibitory effect of lycorine on MERS-CoV, SARS-CoV, and SARS-CoV-2 infections, and then quantitatively measured the inhibitory effect of lycorine on MERS-CoV RdRp activity using a cell-based reporter assay. Finally, we performed the docking simulation with lycorine and SARS-CoV-2 RdRp.

RESULTS

Lycorine efficiently inhibited these CoVs with IC₅₀ values of 2.123 ± 0.053, 1.021 ± 0.025, and 0.878 ± 0.022 μM, respectively, comparable with anti-CoV effects of remdesivir. Lycorine directly inhibited MERS-CoV RdRp activity with an IC₅₀ of 1.406 ± 0.260 μM, compared with remdesivir's IC₅₀ value of 6.335 ± 0.731 μM. In addition, docking simulation showed that lycorine interacts with SARS-CoV-2 RdRp at the Asp623, Asn691, and Ser759 residues through hydrogen bonding, at which the binding affinities of lycorine (-6.2 kcal/mol) were higher than those of remdesivir (-4.7 kcal/mol).

CONCLUSIONS

Lycorine is a potent non-nucleoside direct-acting antiviral against emerging coronavirus infections and acts by inhibiting viral RdRp activity; therefore, lycorine may be a candidate against the current COVID-19 pandemic.

A Cell-Based Reporter Assay for Screening Inhibitors of MERS Coronavirus RNA-Dependent RNA Polymerase Activity

Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19) are emerging zoonotic diseases caused by coronavirus (CoV) infections. The viral RNA-dependent RNA polymerase (RdRp) has been suggested as a valuable target for antiviral therapeutics because the sequence homology of CoV RdRp is highly conserved. We established a cell-based reporter assay for MERS-CoV RdRp activity to test viral polymerase inhibitors. The cell-based reporter system was composed of the bicistronic reporter construct and the MERS-CoV nsp12 plasmid construct. Among the tested nine viral polymerase inhibitors, ribavirin, sofosbuvir, favipiravir, lamivudine, zidovudine, valacyclovir, vidarabine, dasabuvir, and remdesivir, only remdesivir exhibited a dose-dependent inhibition. Meanwhile, the Z-factor and Z'-factor of this assay for screening inhibitors of MERS-CoV RdRp activity were 0.778 and 0.782, respectively. Ribavirin and favipiravir did not inhibit the MERS-CoV RdRp activity, and non-nucleoside HCV RdRp inhibitor, dasabuvir, partially inhibited MERS-CoV RdRp activity. Taken together, the cell-based reporter assay for MERS-CoV RdRp activity confirmed remdesivir as a direct inhibitor of MERS-CoV RdRp in cells. A cell-based MERS-CoV RdRp activity reporter assay is reliable and accurate for screening MERS-CoV RdRp-specific inhibitors. It may provide a valuable platform for developing antiviral drugs for emerging CoV infections.

Synthesis and biological evaluation of 3-acyl-2-phenylamino-1,4-dihydroquinolin-4(1H)-one derivatives as potential MERS-CoV inhibitors

3-Acyl-2-phenylamino-1,4-dihydroquinolin-4(1H)-one derivatives were synthesized and evaluated to show high anti-MERS-CoV inhibitory activities. Among them, 6,8-difluoro-3-isobutyryl-2-((2,3,4-trifluorophenyl)amino)quinolin-4(1H)-one (6u) exhibits high inhibitory effect (IC50 = 86 nM) and low toxicity (CC50 > 25 μM). Moreover, it shows good metabolic stability, low hERG binding affinity, no cytotoxicity, and good in vivo PK properties.

Study on the 2-Phenylchroman-4-One Derivatives and their anti-MERS-CoV Activities

Study on the 2-phenylchroman-4-one derivatives and their anti-MERS-CoVactivities.

SIRT2 reduces actin polymerization and cell migration through deacetylation and degradation of HSP90

SIRT2, a member of the class III histone deacetylase family, has been identified as a tumor suppressor, which is associated with various cellular processes including metabolism and proliferation. However, the effects of SIRT2 on cancer cell migration caused by cytoskeletal rearrangement remain uncertain. Here we show that SIRT2 inhibits cell motility by suppressing actin polymerization. SIRT2 regulates actin dynamics through HSP90 destabilization and subsequent repression of LIM kinase (LIMK) 1/cofilin pathway. SIRT2 directly interacts with HSP90 and regulates its acetylation and ubiquitination. In addition, the deacetylase activity of SIRT2 is required for the regulation of actin polymerization and the ubiquitin-mediated proteasomal degradation of HSP90 induced by SIRT2.

HSV-1 ICP27 represses NF-κB activity by regulating Daxx sumoylation

Herpes simplex virus type 1 ICP27 is a multifunctional protein responsible for viral replication, late gene expression, and reactivation from latency. ICP27 interacts with various cellular proteins, including Daxx. However, the role of interaction between ICP27 and Daxx is largely unknown. Since Daxx is known to repress NF-κB activity, there is a possibility that ICP27 may influence the inhibitory effect of Daxx on NF-κB activity. In this study, we tested whether ICP27 affects the NF-κB activity through its interaction with Daxx. Interestingly, ICP27 enhanced the Daxx-mediated repression of NF-κB activity. In addition, we found that sumoylation of Daxx regulates its interaction with p65. ICP27 binds to Daxx, inhibits Daxx sumoylation, and enhances p65 deacetylation induced by Daxx. Consequently, ICP27 represses the NF-κB activity, by elevating the inhibitory effect of Daxx on NF-κB activity through desumoylation of Daxx.

HSV-1 ICP27 induces apoptosis by promoting Bax translocation to mitochondria through interacting with 14-3-3θ

The subcellular localization of Bax plays a crucial role during apoptosis. In response to apoptotic stimuli, Bax translocates from the cytoplasm to the mitochondria, where it promotes the release of cytochrome c to the cytoplasm. In cells infected with HSV-1, apoptosis is triggered or blocked by diverse mechanisms. In this study, we demonstrate how HSV-1 ICP27 induces apoptosis and modulates mitochondrial membrane potential in HEK 293T cells. We found that ICP27 interacts with 14-3-3θ which sequesters Bax to the cytoplasm. In addition, ICP27 promotes the translocation of Bax to the mitochondria by inhibiting the interaction between 14-3-3θ and Bax. Our findings may provide a novel apoptotic regulatory pathway induced by ICP27 during HSV-1 infection.

VBP1 represses cancer metastasis by enhancing HIF-1α degradation induced by pVHL

von Hippel-Lindau-binding protein 1 (VBP1) physically interacts with pVHL, an E3-ubiquitin ligase, which degrades HIF-1α in an oxygen-dependent manner. HIF-1 is a key regulator of adaptive responses to a lack of oxygen that controls glucose metabolism, angiogenesis, proliferation, invasion, and metastasis. However, the role of VBP1 in pVHL-mediated degradation of HIF-1α is not yet known. In this study, we show that VBP1 enhances the stability of pVHL and facilitates pVHL-mediated ubiquitination of HIF-1α. Furthermore, VBP1 suppresses HIF-1α-induced epithelial-mesenchymal transition in vitro and tumor metastasis in vivo. These findings suggest that VBP1 is a bona fide tumor suppressor protein associated with HIF-1α regulation.

Efficacy of Pre- and Postoperative Chemotherapy in Patients with Osteosarcoma of the Extremities

PURPOSE

We evaluated the treatment efficacy including survival and recurrence, and factors associated with recurrence in osteosarcoma patients treated with preoperative chemotherapy, surgery, and adjuvant chemotherapy.

MATERIALS AND METHODS

Forty nine patients with osteosarcoma were treated with preoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion for 3 cycles, followed by surgery. According to the pathologic response, if tumor was necrotized more than 90%, the same adjuvant chemotherapy was reintroduced for 3 cycles, and if the response was not enough, then the salvage regimen was introduced. Plain chest film and chest CT scan were taken monthly and every 3 months, respectively. When tumor recurred, the metastasectomy was performed whenever possible.

RESULTS

Forty three patients were evaluable with amedian follow up of 53 months. Five-year disease-free and overallsurvival rate was 47.0% and 66.9%, respectively. The recurrence was observed in 22 patients (51.2%) with median time of 12.5 months. Baseline alkaline phosphatase (ALP) was the only significant factor for recurrence (p=0.03) and the patients with the possibility of metastasectomy recurrence showed higher post-relapse survival compared to other treatment modalities (26 momths vs 5~12 months).

CONCLUSION

These results indicates that pre- and postoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion showed comparable treatment efficacy and acceptable toxicities.

Aqueous extract of Tribulus terrestris Linn induces cell growth arrest and apoptosis by down-regulating NF-κB signaling in liver cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

A medicinal herb Tribulus terrestris Linn has been used to treat various diseases including hepatocellular carcinoma. The aim of the present study was to investigate the anticancer activity of Tribulus terrestris Linn (TT) in liver cancer cells.

MATERIALS AND METHODS

The antitumor activity of aqueous TT extract was analyzed by testing the cytotoxicity and the effect on clonogenecity in HepG2 cells. Apoptosis and cell cycle arrest induced by TT were dissected by flow cytometry and its inhibitory effect on NF-κB activity was determined by analyzing the expression levels of NF-κB/IκB subunit proteins. The suppression of NF-κB-regulated gene expression by TT was assessed by RT-PCR.

RESULTS

TT extract repressed clonogenecity and proliferation, induced apoptosis, and enhanced accumulation in the G0/G1 phase of liver cancer cells. It also turned out that TT extract inhibited NF-κB-dependent reporter gene expression and NF-κB subunit p50 expression, while it enhanced the cellular level of IκBα by inhibiting the phosphorylation and degradation of IκBα. In addition, IKK activity was inhibited in a dose-dependent manner. Furthermore, TT extract suppressed the transcription of genes associated with cell cycle regulation, anti-apoptosis, and invasion.

CONCLUSION

These data showed that TT extract blocks proliferation and induces apoptosis in human liver cancer cells through the inhibition of NF-κB signaling. Aqueous TT extract can be used as an anticancer drug for hepatocellular carcinoma patients.

Synthesis of stable silica-dye hybrid nanomaterial as DNA carrier

A new method is proposed for the fabrication of fluorescence-labeled and amine-modified silica nanoparticles for application as nonviral vectors in gene delivery. Highly monodisperse, stable fluorescent silica nanoparticles were prepared using 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene and the water-in-oil microemulsion method. The green-fluorescent-protein gene can be easily combined onto the positively charged surfaces of nanoparticles to form a nanoparticle-DNA complex. The nanoparticle-DNA complex successfully passed through various barriers into the HeLa and HEK 293 K cells. The cytotoxicity of the PEI-coated and BBOT-encapsulated silica nanoparticles on both the HeLa and HEK 293T cell lines was found to be at an acceptable level for use as gene carriers when the particle concentration was below 125 microg/ml. The fluorescence intracellular images confirm the successful delivery of the nanoparticle-DNA complex and gene expression. The present work suggests the potential use of dye-incorporated silica nanoparticles in nonviral gene delivery.

Sonochemical preparation of silica nanorods for gene delivery using single-walled carbon nanotubes as templates

Silica nanorods were fabricated with single-walled carbon nanotubes (SWCNTs) via ultrasound. The diameter of the resulting SWCNT-silica particles ranged from 60 to 70 nm. The morphology of this composite material was investigated via scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The individual SWCNTs are uniformly coated with silica and formed a unique nanocomposite material. The important role of ultrasound and the mechanism of silica layer formation on SWCNTs were explained via the hydrolysis of the silica source and the adsorption of the siloxane groups on the SWCNT surfaces under ultrasound irradiation. The amino-functionalized silica nanorods were demonstrated as non-viral vectors for gene delivery.

Antiviral effect of Curcuma longa Linn extract against hepatitis B virus replication

ETHNOPHARMACOLOGICAL RELEVANCE

A medicinal herb Curcuma longa Linn has been used for treating various liver diseases caused by hepatitis B virus (HBV) in Asia.

AIM OF THE STUDY

The study was performed in order to investigate the antiviral activity of Curcuma longa Linn against HBV replication in liver cells.

MATERIALS AND METHODS

Aqueous extract of Curcuma longa Linn (CLL) was prepared and used to analyze its antiviral activity against HBV replication in HepG 2.2.15 cells, which contain HBV genomes. The inhibitory effect of CLL on HBV replication was examined by testing the levels of secreted HBV surface antigens (HBsAg), HBV DNAs, and HBV RNAs in HepG 2.2.15 cells using ELISA, Southern blot, and Northern blot analyses. Cytotoxic activities of CLL extract on various liver cells were analyzed by MTT assay. To dissect the inhibitory mechanism of CLL extract on HBV replication, the levels of p53 protein and p53 mRNAs were analyzed by Western blot and RT-PCR in HepG 2.2.15 cells. The repression of CLL extract on HBV transcription was analyzed by RT-PCR and CAT assay.

RESULTS

CLL extract repressed the secretion of HBsAg from HepG 2.2.15 cells. CLL extract also suppressed the production of HBV particles and the level of intracellular HBV RNAs in HepG 2.2.15 cells, suggesting that CLL extract inhibits HBV replication. We found that the anti-HBV activity of CLL extract is mediated through enhancing the cellular accumulation of p53 protein by transactivating the transcription of p53 gene as well as increasing the stability of p53 protein. It turned out that CLL extract repressed the transcription of HBx gene by suppressing HBV enhancer I and X promoter through p53 protein. In addition, CLL extract did not have any cytotoxic effects on liver cells.

CONCLUSION

These data showed that CLL extract represses HBV replication through enhancing the level of p53 protein. CLL extract can be used as a safe and specific drug for patients with liver diseases caused by HBV infection.

HSV-1 ICP27 suppresses NF-kappaB activity by stabilizing IkappaBalpha

Nuclear factor kappaB (NF-kappaB) is associated with the transcriptional activation of genes encoding chemokines, adhesion molecules, cytokines, and anti-apoptotic proteins, which are key components in immune responses and viral infection. Many viruses modulate NF-kappaB through numerous viral gene products to allow productive infections and immune escape. Here we report that herpes simplex virus-1 infected cell protein 27 (HSV-1 ICP27), an immediate early protein of HSV-1, represses NF-kappaB activity through binding to inhibitor of kappaB (IkappaBalpha), blocking phosphorylation and ubiquitination of IkappaBalpha, and stabilizing IkappaBalpha. These data may explain how NF-kappaB activity is regulated by ICP27 to escape immune responses during the very early period of HSV-1 infection.

Control of microorganisms and reduction of biogenic amines in chicken breast and thigh by irradiation and organic acids

The effect of irradiation or organic acid treatment of raw chicken breast and thigh meat to control inoculated microorganisms and the production of biogenic amines (BA) was studied. Bacillus cereus, Enterobacter cloacae, and Alcaligenes faecalis were selected and inoculated into raw ground chicken breast and thigh meat at approximately 10(7) cfu/g. The samples were irradiated at 0, 0.5, 1, and 2 kGy or mixed with a 0.2 M solution of acetic, citric, or lactic acid (1 mL for 10 g of meat sample) for 24 h at 4 degrees C. Viable cell counts and BA contents were determined. Irradiation was effective in reducing the inoculated bacteria: 0.5 kGy achieved approximately a 2-log reduction, and no viable cells were detected at a dose of 2 kGy. In contrast, only up to a 1-log reduction was achieved by organic acid treatment except for citric acid, which achieved approximately a 3-log reduction of E. cloacae. Both the irradiation and organic acid treatment of raw chicken breast and thigh reduced the BA content, but the rate of BA reduction differed by inoculated organism and treatment (irradiation or organic acid). Although irradiation was an excellent method for controlling inoculated microorganisms, the content of BA produced was similar to that of the organic acid treatment of raw chicken breast and thigh meat.

Phase III trial of adjuvant 5-fluorouracil and adriamycin versus 5-fluorouracil, adriamycin, and polyadenylic-polyuridylic acid (poly A:U) for locally advanced gastric cancer after curative surgery: final results of 15-year follow-up

BACKGROUND

This phase III trial was to compare 5-fluorouracil (5-FU), adriamycin, and polyadenylic-polyuridylic acid (poly A:U) against 5-fluorouracil plus adriamycin (FA) for operable gastric cancer.

PATIENTS AND METHODS

From 1984 to 1989, patients who had D(2-3) curative resection were randomly assigned to receive chemotherapy or chemoimmunotherapy. Chemotherapy consisted of 12 mg/kg 5-FU every week for 18 months and 40 mg/m2 adriamycin every 3 weeks for 12 cycles. Chemoimmunotherapy consisted of FA plus 100 mg of poly A:U weekly for six cycles and was followed 6 months later by six weekly 50-mg booster injections.

RESULTS

A total of 292 patients were enrolled. After excluding 12 ineligible patients, 142 and 138 patients were allocated to each treatment. Patients were balanced with prognostic variables: age, sex, tumor location, differentiation, degree of tumor invasion (T2-T4a), and lymph node status (N0-N2). During the 15-year follow-up, chemoimmunotherapy significantly prolonged overall (P = 0.013) and recurrence-free (P = 0.005) survivals compared with chemotherapy alone. The survival benefits were prominent in the subset of patients with T3/T4a, N2, or stage III. Treatments were generally well tolerated in both arms.

CONCLUSIONS

These results indicate a survival advantage of chemoimmunotherapy with a regimen of FA and poly A:U in curatively resected gastric adenocarcinoma.

The prognosis of stage IV gastric carcinoma patients after curative resection

BACKGROUND/AIMS

In the UICC staging system, stage IV contains not only those patients with distant metastasis but also patients with far-advanced T and N status but without distant metastasis. We investigated the prognostic factors of stage IV gastric carcinoma patients, without distant metastasis after curative resection and the role of surgery.

METHODOLOGY

One hundred and ninety stage IV gastric carcinoma patients, without distant metastasis were reviewed after curative resection in our hospital from January 1987 to December 1996.

RESULTS

Male sex, distal third location, diffuse or infiltrative type and histologically undifferentiated type were common. Of the 190 patients, 52 (27.4%) patients lived more than 3 years. The lymph node ratio (positive lymph node/retrieved lymph node) and combined resection independently affected survival (P = 0.0013, 0.0061, respectively). The perigastric lymph node ratio was well correlated with overall lymph node ratio (r = 0.794, P < 0.001).

CONCLUSIONS

With the involvement of an adjacent organ and knowing the perigastric lymph node ratio, the surgeon can decide upon the extent of dissection and postoperative treatment. However, a prospective study is warranted.

DNA ploidy patterns in advanced gastric carcinoma; is it a clinically applicable prognosticator?

BACKGROUND/AIMS

The purpose of this study was to evaluate the prognostic significance of ploidy patterns as determined by flow cytometry in terms of clinical usefulness.

METHODOLOGY

270 patients with a diagnosis of advanced gastric carcinoma were studied with fresh specimens obtained from multiple site avoiding nonviable or nonneoplastic tissues by DNA flow cytometry. DNA ploidy and clinicopathologic factors were compared and survival was analyzed.

RESULTS

The mean age of the patients was 56.1 +/- 11.6 years (25-80 years). There were 195 males and 75 females. Aneuploidy was shown in 93 (35.9%) patients. Male sex and differentiated tumor were more frequent in aneuploidy than diploidy (P = 0.011, < 0.001, respectively). By univariate analysis, tumor location, size, extent of resection, curative resection, serosa invasion, lymph node involvement, and distant metastasis significantly affected survival but not aneuploidy. Significant independent prognostic factors by multivariate analysis were curative resection, serosa invasion and lymph node involvement (P = 0.0001, 0.0114, 0.0262, respectively).

CONCLUSIONS

DNA ploidy patterns of advanced gastric carcinoma are of limited clinical significance, therefore not a clinically applicable prognosticator.

Ultralow anterior resection and coloanal anastomosis for distal rectal cancer: functional and oncological results

We evaluated the functional and oncological outcome of ultralow anterior resection and coloanal anastomosis (CAA), which is a popular technique for preserving anal sphincter in patients with distal rectal cancer. Forty-eight patients were followed up for 6-100 months regarding fecal or gas incontinence, frequency of bowel movement, and local or systemic recurrence. The main operative techniques were total mesorectal excision with autonomic nerve preservation; the type of anastomosis was straight CAA, performed by the perianal hand sewn method in 38 cases and by the double-stapled method in 10. Postoperative complications included transient urinary retention (n=7), anastomotic stenosis (n=3), anastomotic leakage (n=3), rectovaginal fistula (n=2), and cancer positive margin (n=1; patient refused reoperation). Overall there were recurrences in seven patients (14.5%): one local and one systemic recurrence in stage B2; and one local, two systemic, and two combined local and systemic in C2. The mean frequency of bowel movements was 6.1 per day after 3 months, 4.4 after 1 year, and 3.1 after 2 years. The Kirwan grade for fecal incontinence was 2.7 after 3 months, 1.8 after 1 year, and 1.5 after 2 years. With careful selection of patients and good operative technique, CAA can be performed safely in distal rectal cancer. Normal continence and acceptable frequency of bowel movements can be obtained within 1 year after operation without compromising the rate of local recurrence.

p53, BCL-2, and Ki-67 expression according to tumor response after concurrent chemoradiotherapy for advanced rectal cancer

BACKGROUND

Concurrent chemoradiotherapy (CCRT) for locally advanced rectal cancer is an important modality for curative resection, but tumors show wide spectrum response. The purpose of this study was to investigate any correlation among related genetic mutations, proliferative index, and tumor response after CCRT.

METHODS

This study included 23 patients with rectal cancer, who were preoperatively staged as at least T3 N1 or T4 (determined by transrectal ultrasonography and MRI). Enrolled patients were given 5-FU 450 mg/m2/day and leucovorin 20 mg/m2/day intravenously for 5 days during weeks 1 and 5 of radiotherapy (45-54 Gy). Surgical resection was performed 4 weeks after completion of the scheduled treatment. Tumor response was classified as CR (complete response), PR (partial response: 50% diminution of tumor volume and downstaging), and NR (no response). Paraffin-embedded tissue obtained before chemoradiotherapy was studied by immunohistochemical staining for p53, BCL-2, and Ki-67. The extent of tumor response was correlated with proliferative activity and was measured by immunostaining Ki-67 proliferative antigen and the expression of p53 and BCL-2 oncoproteins.

RESULTS

All patients were resectable. CR was obtained in 4 patients, PR in 10 patients, and NR in 9 patients. The p53 mutation was noted in 16 patients: NR in 5 patients, PR in 9 patients, and CR in 2 patients (P = .638). BCL-2 expression was noted in 11 patients: NR in 4 patients, PR in 3 patients, and CR in 4 patients (P = .799). The Ki-67 labeling index was NR: 615.4+/-47.2; PR: 663.2+/-20.4; and CR: 765.5+/-58.3 (CR + PR vs. NR, P = .029).

CONCLUSIONS

Immunohistochemical expression of p53 and BCL-2 does not correlate with tumor response after CCRT, but Ki-67 labeling may be a useful parameter for radiosensitive tumors selected for CCRT.

Impact of splenectomy for lymph node dissection on long-term surgical outcome in gastric cancer

BACKGROUND

In the treatment of gastric cancer, splenectomy is performed for effective lymph node dissection around the splenic artery and splenic hilum. The purpose of this study was to clarify the long-term outcome of splenectomy in the treatment of gastric cancer.

METHODS

The effect of splenectomy on recurrence and prognosis was examined in a retrospective analysis of 665 patients who had undergone curative total gastrectomy for gastric carcinoma from 1987 to 1996. The risk factors associated with recurrence and prognosis were investigated by univariate and multivariate analysis.

RESULTS

The splenectomy group showed more advanced lesions and a higher recurrence rate than the spleen-preserved group. However, after adjusting for the TNM (tumor, node, metastasis) stage, there was no significant difference in recurrence rate and pattern between the two groups. Logistic regression analysis revealed that gross type, serosal invasion, and nodal metastasis were independent risk factors for recurrence while splenectomy was not. When comparing patients with the same TNM (tumor, node, metastasis) stages, no significant difference in the 5-year survival rates was apparent. Multivariate analysis demonstrated that age, serosal invasion, and nodal metastasis were independent prognostic factors whereas splenectomy was not.

CONCLUSIONS

These data suggest that splenectomy for lymph node dissection in gastric cancer is not effective regarding long-term patient prognosis.

Monthly 5-days 5-fluorouracil and low-dose leucovorin for adjuvant chemotherapy in colon cancer

We investigated the dose-related effect of the 5-fluorouracil (5-FU)/leucovorin regimen on survival in 139 colon cancer patients with Dukes' B2 and C2 stage disease. Chemotherapy consisted of 400 mg/m(2) of 5-FU and 20 mg/m(2) of leucovorin injected daily for 5 days in every 4 weeks for a maximum of 12 cycles. The total dose of 5-FU administered per body surface area had a significant effect on the 5-year disease-free survival and 5-year overall survival in stage B2 and C2 colon cancer patients (P=0.0018, P=0.0011). Analysis with reference to the median DSDI demonstrated that there was a significant difference in 5-year survival in Dukes' C2 (P=0.0016), but survival was not affected by the dose intensity. Multivariate analysis demonstrated that only the total dose of 5-FU administered per surface area affected the 5-year disease-free survival and 5-year overall survival (P=0.0016, P=0.0007, respectively). It can be concluded that the total dose of 5-FU administered is important in planned dosage schedule of adjuvant chemotherapy in colon cancer.

Adjuvant 5-fluorouracil plus doxorubicin in D2-3 resected gastric carcinoma: 15-year experience at a single institute

BACKGROUND

The authors evaluated the efficacy of adjuvant chemotherapy with 5-fluorouracil (5-FU) plus doxorubicin in gastric carcinoma after D2-3 curative resection. They also evaluated the effect of dose-related factors (delivered total dose/m(2), actual dose intensity [ADI], relative dose intensity [RDI]) of this regimen on patient survival.

METHODS

A total of 301 patients with Stage II to IV (en bloc resected T4b; 1984 American Joint Committee on Cancer staging) were accrued between 1984 and 1996. Chemotherapy was started within 4 weeks of surgery according to the following schedule: intravenous bolus injection of doxorubicin 40 mg/m2 every 3 weeks for 12 cycles and 5-FU 400 mg/m2 weekly for 60 weeks. The toxicity and survival were evaluated.

RESULTS

The median follow-up duration was 58 months. Sixty-four percent of the total patients and 71.7% of the patients who did not experience recurrence during the chemotherapy finished the protocol completely with acceptable toxicities. The 5- and 10-year disease free survival rates of total 301 patients were 58.4% and 46.5%, and the overall survival rates were 62.1% and 50.5%, respectively. Treatment completion group showed survival benefit over the early termination group in 5-year survival (75.2% vs. 52.9%; P = 0.0005). The median ADI of 5-FU and doxorubicin were 349 and 11 mg/m2/week, and the median RDIs of 5-FU and doxorubicin were 0.87 and 0.83, respectively. Multivariate analysis demonstrated that completion of chemotherapy is an independent prognostic factor of both disease free and overall survival. However, ADI and RDI did now show any effect on survival.

CONCLUSIONS

Adjuvant chemotherapy with 5-FU plus doxorubicin for 60 weeks after D2-3 dissection induced promising survival duration with acceptable toxicities. Full administration of the planned dosage of the combined drugs is recommendable as opposed to early termination of the chemotherapy in gastric carcinoma.

Preoperative chemoradiotherapy with oral doxifluridine plus low-dose oral leucovorin in unresectable primary rectal cancer

PURPOSE

The use of oral chemotherapeutic agents in chemoradiotherapy provides several advantages. Doxifluridine, an oral 5-FU prodrug, has been shown to be effective in colorectal cancer. We attempted a Phase II trial of preoperative chemoradiotherapy with doxifluridine plus a low-dose oral leucovorin in unresectable primary rectal cancer patients. In this study, toxicity and efficacy were evaluated.

METHODS AND MATERIALS

There were 23 patients with primary unresectable rectal cancer in this trial, 21 of whom were available for analysis. The patients were treated with oral doxifluridine (900 mg/day) plus oral leucovorin (30 mg/day) from days 1 to 35, and pelvic radiation of 45 Gy over 5 weeks. Surgical resection was performed 5-6 weeks after the treatment.

RESULTS

Acute toxicity involved thrombocytopenia, nausea/vomiting, diarrhea, and skin reaction. All were in Grade 1/2, except diarrhea, which was not only the most frequent (7 patients, 33.3%), but also the only toxicity of Grade 3 (2 patients). The clinical tumor response was shown in 5 patients (23.8%) as a complete response and 13 patients (61.9%) as a partial response. A complete resection with negative resection margin was done in 18 patients (85.7%), in 2 of whom a pathologic complete response was shown (9.5%). The overall downstaging rate in the T- and N-stage groupings was 71.4% (15 patients).

CONCLUSION

This study demonstrated the efficacy and low toxicity of chemoradiotherapy with doxifluridine. Currently, a Phase III randomized trial of chemoradiotherapy is ongoing at our institute to compare the therapeutic efficacy of oral 5-FU with respect to i.v. 5-FU in locally advanced and unresectable rectal cancer.

Early postoperative intraperitoneal chemotherapy with mitomycin C, 5-fluorouracil and cisplatin for advanced gastric cancer

OBJECTIVE

The long-term survival of patients who undergo surgery for stage IV gastric cancer is poor, due to metastatic spread of the tumor. Intraperitoneal chemotherapy (IPT) as a possible treatment for peritoneal dissemination has been investigated in a number of different tumors. The aim of this study was to investigate the toxicity and impact of early postoperative IPT on the survival of patients with advanced gastric cancer.

METHODS

Between 1993 and 1997, a total of 91 patients with stage IV gastric cancer who underwent potentially curative or palliative resection received intraperitoneal mitomycin C before closure of the abdominal wound. 5-Fluorouracil and cisplatin were administered intraperitoneally on postoperative days 1-4, and this was repeated at 4-week intervals.

RESULTS

All patients received a median of 3 IPT perfusions. There were 24 (26.4%) postoperative complications and 1 (1.1%) mortality. The most frequent hematologic toxicity (grade 3-4) was leukopenia. The major nonhematologic toxicities (grade 3-4) were emesis and nephrotoxicity. After a median follow-up period of 26 months, 14 patients remain alive without evidence of recurrence, whereas 75 patients died due to recurrence or progression of disease. The median survival period for all 91 patients was 15.4 months. When survival according to the residual tumor was analyzed, median survival was 36.0 months in the R0 (curative resection) group, 20.6 months in the R1 group (margins of resected specimens showing microscopic residual tumor or diameter of each residual tumor less than 3 mm) and 9.0 months in the R2 group (macroscopic residual tumor larger than 3 mm) (p < 0.001).

CONCLUSIONS

IPT was found to be safe, and it appears to improve the prognosis in patients with minimal residual tumors. However, complete cytoreductive surgery is mandatory for achieving the beneficial effect of IPT.

Intravenous 5-fluorouracil versus oral doxifluridine as preoperative concurrent chemoradiation for locally advanced rectal cancer: prospective randomized trials

BACKGROUND

Preoperative radiation treatment with concomitant intravenous infusion of 5-fluorouracil (5-FU) is known to be effective in shrinking and downstaging of tumors. However, chemotherapy has often been limited by its toxicity and poor patient compliance. Oral 5-FU is known to have several advantages over conventional intravenous 5-FU infusion such as lower toxicity and higher quality of life without compromising the efficacy of the treatment. The aim of this study was to compare intravenous 5-FU with oral doxifluridine with respect to tumor response, toxicity and quality of life.

METHODS

Twenty-eight patients with rectal cancer, staged as over T3N1 or T4 by transrectal ultrasonography between July 1997 and December 1998, were included in this study. Intravenous 5-FU (450 mg/m2) and leucovorin (20 mg/m2) were given for five consecutive days during the first and fifth weeks of radiation therapy (50.4 Gy) (n = 14). Oral doxifluridine (700 mg/m2/day) and leucovorin (20 mg/m2) were given daily during radiation treatment (n = 14). Quality of life was scored according to 22 activity items (good, >77; fair, >58; poor, <57). Surgical resection was performed 4 weeks after completion of concurrent chemoradiation treatment. Tumor response was classified into CR (complete remission), PR (partial response; 50% diminution of tumor volume or downstaging ) and NR (no response).

RESULTS

Tumor response was CR 3/14 (21.4%), PR 7/14 (50%) and NR 4/14 (28.6%) in the IV arm versus CR 2/14 (14.2%), PR 6/14 (42.9%) and NR 6/14 (42.9%) in the Oral arm (p = 0.16, 0.23, 0.24), respectively. The quality of life was poor (36.4% versus 33.3%), fair and good (63.6% versus 66.7%) between the IV arm and Oral arm, respectively. Gastrointestinal toxicity was 2/14 (14.3%) in the IV arm versus 5/14 (35.7%) in the Oral arm, respectively. Stomatitis was only observed in the IV arm (1/14, 7.1%). Hematological toxicity was 3/14 (21.4%) in the IV arm versus 4/14 (28.5%) in the Oral arm, respectively. Systemic recurrence during the follow-up periods were 1/14 (7.1%) in the IV arm and 2/14 (14.3%) in the Oral arm, respectively (p = 0.307). One local recurrence was observed in the Oral arm.

CONCLUSION

Even though the results were not entirely reliable owing to the small number of patients enrolled, oral doxifluridine-based chemotherapy as preoperative chemoradiation for advanced rectal cancer did not show any significant advantages over intravenous infusion.

Frameshift mutations at coding mononucleotide repeats of the hRAD50 gene in gastrointestinal carcinomas with microsatellite instability

Microsatellite instability (MSI) and frameshift mutations in genes containing nucleotide repeats have been reported in a subset of colorectal and gastric carcinomas. This study describes the analysis of MSI-positive colorectal (39 cases) and gastric carcinomas (36 cases) for the presence of frameshift mutations of the six genes known to be involved in DNA repair and containing mononucleotide repeats in their coding region. Our mutational study of the 75 MSI-positive tumors revealed frequent mutations in hRAD50 (23 cases, 31%), BLM (16 cases, 21%), and hMSH6 (16 cases, 21%); rare mutations in BRCA1 (1 case, 1%) and ATM (3 cases, 4%); and no mutation in NBS1. In contrast, no frameshift mutation was found in 60 MSI-negative colorectal and gastric carcinomas. The mutation of hRAD50, a gene that is involved in the response to cellular DNA damage and forms a complex with hMRE11 and NBS1, has not been reported previously. Our results suggest that frameshift mutations of hRAD50, BLM, and hMSH6 are selected and play a role in the tumorigenesis of colorectal and gastric carcinomas with MSI. The MSI targeting of the hRAD50 and BLM genes represents an additional link between MSI and DNA repair because alteration of these genes could accelerate defective DNA repair.

Preoperative staging of rectal cancer with MRI: accuracy and clinical usefulness

BACKGROUND

Preoperative staging is essential for planning of optimal therapy for patients with rectal cancer. Recently, magnetic resonance imaging (MRI) is used frequently because of its benefits of clear pelvic image are better than other diagnostic methods. The purpose of this study was to determine accuracy rates and clinical usefulness of MRI in preoperative staging of rectal cancer.

METHODS

Between February, 1997, and December, 1999, 217 patients with histologically proven rectal cancer were staged preoperatively and had surgical resections performed. MRI criteria for depth of invasion was determined by the degree of disruption of the rectal wall. Metastatic perirectal lymph nodes were considered to be present if they showed heterogenous texture, irregular margin, and enlargement (>10 mm).

RESULTS

The accuracy of the MRI for determining depth of invasion was 176/217 (81%) and regional lymph node invasion was 110/217 (63%). In the T stage, accuracy rate of T1 was 3/4 (75%), T2 was 20/37 (54%), T3 was 141/162 (87%), and T4 was 12/14 (86%), respectively. The specificity of lymph node invasion was 45/110 (41%) and the sensitivity was 91/107 (85%). The accuracy rate of regional lymph node involvement was 136/217 (63%). T1 and T2 were overstaged in 1/4 (25%) and 17/37 (46%), respectively, and T3 was understaged in 15/162 (9.2%). The accuracy rate to detect metastatic lateral pelvic lymph node was 4/14 (29%) after lateral pelvic lymph node dissection was done in 14 patients under MRI. The accuracy rate in assessing levator ani muscle tumor involvement was 8/11 (72%).

CONCLUSIONS

MRI showed a good, comparable accuracy rate for determining depth of tumor invasion, compared with transrectal ultrasonography, which still has a low accuracy rate for detecting metastatic lymph node. MRI with endorectal coil may increase the accuracy rate of T1 and T2 lesions. In addition, clear sagittal and coronal sectional pelvic images can give a lot of information about adjacent organ invasion or any invasion of levator ani muscle. MRI can be useful for choosing an appropriate extent of lymph node dissection and type of surgery.

A prospective randomized trial comparing intravenous 5-fluorouracil and oral doxifluridine as postoperative adjuvant treatment for advanced rectal cancer

BACKGROUND

Postoperative adjuvant chemoradiation treatment after curative resection for rectal cancer was needed to reduce recurrence and improve a survival rate. Intravenous 5-fluorouracil (5-FU) and leucovorin has been a mainstay of chemotherapy, but oral 5-FU derivatives have been shown a comparable antitumor activity. Intravenous 5-FU and oral doxifluridine were compared with respect to therapeutic efficacy, drug toxicity, and quality of life.

METHODS

A total of 166 patients were randomized to receive intravenous 5-FU (450 mg/m2/day) or oral doxifluridine (900 mg/m2/day) in combination with leucovorin (20 mg/m2/day) for depth of invasion, nodal status, metastasis (TNM) stage II and III patients between October 1997 and February 1999. Consecutive daily intravenous infusion for 5 days per every month for a total of 12 cycles (IV arm, n = 74) and oral doxifluridine daily for 3 weeks and 1 week rest for a total of 12 cycles (oral arm, n = 92). Drug toxicity and quality of life were observed. Quality of life was scored according to 22 daily activity items (good, > or =71; fair, < 70; poor, < 52).

RESULTS

There was no difference of sex between two groups (IV arm: male/female = 45/29, oral arm: male/female = 59/33). The mean age was 52.3 vs. 59.5, respectively. There was also no difference of TNM stage distribution and type of operation between groups (P>.05). Mean numbers of chemotherapy cycles were 6.5+/-3.7 (IV arm) vs. 7.2+/-4.3 (oral arm), respectively. The rate of recurrence was 9/74 (12.1%) in the IV arm and 6/92 (6.5 %) in the oral arm, respectively (P = .937). Local recurrence was 2/74 (stage III; 2.7%) in the IV arm and 1/92 (stage II; 1.1%) in the oral arm, respectively. Systemic recurrence was 7/74 (stage III; 9.4%) in the IV arm and 5/92 (stage III; 5.4%) in the oral arm, respectively. The most common site of systemic recurrence was the liver. Toxicity profile was as follows: leukopenia (30/74 vs. 17/92) and alopecia (21/74 vs. 13/92) were statistically more common in the IV arm. Diarrhea was more common in the oral arm. Poor quality of life score between two groups was observed at 1 month (23.9% vs. 13%) and 2 months (15.8% vs. 3.7%) after chemotherapy. Good quality of life score was observed at 1 month (19.5% vs. 49%) and 2 months (47% vs. 72%), respectively (P<.05).

CONCLUSIONS

Oral doxifluridine with leucovorin shows a comparable therapeutic efficacy to intravenous 5-FU regimen with high quality of life as postoperative adjuvant therapy. The oral regimen also can be safely given with appropriate toxicity and tolerability.

Restorative proctocolectomy: operative safety and functional outcomes

Restorative proctocolectomy (total proctocolectomy and ileal J pouch anal anastomosis) has been accepted as the operation of choice in the setting of chronic ulcerative colitis and familial adenomatous polyposis. The purpose of this study was to assess operative safety and functional outcome after restorative proctocolectomy. A total of sixteen patients underwent surgery between January 1996 and December 1999. Hand sewn anastomosis with diverting ileostomy was performed in 9 patients and double stapled anastomosis in 7 patients. The underlying disease was ulcerative colitis in 9 cases and familial adenomatous polyposis in 7. Postoperative complications developed in 8 cases (50%), and intestinal obstruction was found in 4 cases (2 cases were operated upon). Anastomosis related complications were stenosis (n=2), leak (n=1) and perianal abscess (n=1). All patients were followed up at the outpatient clinic using questionnaires, with a mean follow up period of 19.9 months. The frequency of bowel movement was 8.2 per day in hand sewn anastomosis (HS), and 12 per day in double stapled anastomosis (DS) 3 months after surgery (period 1). This frequency decreased to 5.5 per day in HS, and 4.6 per day in DS after one year (period 2). Day and night continence was shown in 12/15, and 5/15, respectively in period 1, but improved to 10/11, and 10/11, respectively in period 2. Night time incontinence was noted in 10 of 15 patients in period 1 (seepage 3/15, soiling 7/15). The need to take anti-diarrheal medication, and to use a pad was noted in 2/15, and 10/15, respectively in period 1, but no patient took antidiarrheal medication or wore a protective pad in period 2. Postoperative urinary function was satisfactory in 13/14 patients. Postoperative sexual function was analyzed in a total of 8 patients, who showed good erection (5/5), ejaculation (5/5) and satisfactory sexual life (5/5). In females, 3 patients showed a satisfactory sexual life. In conclusion, restorative proctocolectomy for chronic ulcerative colitis and familial adenomatous polyposis can be performed safely with excellent functional outcomes, including bowel movement, urinary and sexual functions one year after surgery.

Tissue urokinase-type plasminogen activator receptor levels in breast cancer

Cancer invasion is induced by several proteolytic enzyme systems associated with the destruction of basement membrane and extracellular matrix. Urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) have been reported as prognostic factors in breast cancer patients and plasminogen activation is regulated by various factors such as uPAR and growth factors. Thus, we examined the tissue levels of urokinase-type plasminogen activator receptor (uPAR) in breast cancer patients. Tissue uPAR levels were measured by ELISA assay in 268 breast cancer patients. The median and mean values of tissue uPAR level in breast cancer were 3.5 ng/mg cytosol protein and 4.8+/-3.6 ng/mg cytosol protein, respectively. Tissue uPAR level was the highest in T1 stage, but there was no statistical significance between the T stages (p>0.05), nor in nodal stage, in the value of uPAR according to progression. And the value of uPAR expression was not associated with estrogen and progesterone receptor status, number of involved node and percent of node involvement. In TNM stage, tissue uPAR levels were higher in patients with stage I-II than in patients with stage III-IV (p=0.027). In univariate analysis, nodal factor (p=0.002) and TNM stage (p=0.0004) were significant. But, multivariate analysis showed that TNM stage was the only significant prognostic factor (p=0.0002). These results suggest that uPAR is mainly associated with initial tumor invasion and other factors might be involved in later stages of cancer progression.

Correlation of tissue and blood plasminogen activation system in breast cancer

The plasminogen activation system plays a crucial role during cancer invasion and metastasis. In the solid tumor, urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor type-1 (PAI-1) and uPA receptor (uPAR) are considered as prognostic factors. In this study, we have investigated whether secretion of the uPA, PAI-1 and uPAR from the primary breast cancer tissue can be detected in the blood of the patients using the ELISA assay. We have found that the plasminogen activation system (uPA, PAI-1, uPAR) of tumor tissue is activated from the early stage of breast cancer. However, only a number of metastatic lymph nodes was a prognostic factor in multivariate analysis for relapse. The blood level of the plasminogen activation system correlated with that of tissue in an order of uPAR (r(2)=0.61; P=0.001), uPA (r(2)=0.35; P=0.001) and PAI-1 (r(2)=0.11; P=0.001). We conclude that the total uPAR level of cancer tissue can be substituted by that which is detected in the blood for further clinical applications.

Recurrence following curative resection for gastric carcinoma

BACKGROUND

The diagnosis and treatment of recurrent gastric cancer remains difficult. The aim of this study was to determine the risk factors for recurrence of gastric cancer and the prognosis for these patients.

METHODS

Of 2328 patients who underwent curative resection for gastric cancer from 1987 to 1995, 508 whose recurrence was confirmed by clinical examination or reoperation were studied retrospectively. The risk factors that determined the recurrence patterns and timing were investigated by univariate and multivariate analysis.

RESULTS

The mean time to recurrence was 21.8 months and peritoneal recurrence was the most frequent (45.9 per cent). Logistic regression analysis showed that serosal invasion and lymph node metastasis were risk factors for all recurrence patterns and early recurrence (at 24 months or less). In addition, independent risk factors involved in each recurrence pattern included younger age, infiltrative or diffuse type, undifferentiated tumour and total gastrectomy for peritoneal recurrence; older age and larger tumour size for disseminated, haematogenous recurrence; and older age, larger tumour size, infiltrative or diffuse type, proximally located tumour and subtotal gastrectomy for locoregional recurrence. Other risk factors for early recurrence were infiltrative or diffuse type and total gastrectomy. Reoperation for cure was possible in only 19 patients and the mean survival time after conservative treatment or palliative operation was less than 12 months.

CONCLUSION

The risk factors for each recurrence pattern and timing of gastric cancer can be predicted by the clinicopathological features of the primary tumour. Since the results of treatment remain dismal, studies of perioperative adjuvant therapy in an attempt to reduce recurrence are warranted.

Putative chromosomal deletions on 9P, 9Q and 22Q occur preferentially in malignant gastrointestinal stromal tumors

To characterize the type of genetic alterations in gastrointestinal stromal tumors (GISTs), we performed a comprehensive allelotype study of 14 GISTs (2 benign, 7 borderline and 5 malignant) by polymerase-chain-reaction and loss-of-heterozygosity (PCR-LOH) analysis using 102 microsatellite markers, and compared the results with comparative-genomic-hybridization (CGH) analysis. Among the 38 evaluated chromosomal arms, 16 (42.1%) showed LOH in at least one patient. Most frequent LOH was observed at chromosome 14p and 14q (9/14, 64%) and this was demonstrated in all types of GISTs (50% in benign, 71% in borderline and 80% in malignant). Additional chromosomal deletions were found in several chromosomal arms. Among them, deletions on chromosomal arms of 22q (3/14, 21.4%), 9p (2/14, 14.3%) and 9q (2/14, 14.3%) were the most frequent, and were detected only in malignant GISTs both by PCR-LOH and by CGH analysis. Additionally, 2 malignant GISTs with LOH on 9p showed homozygous deletions in the restricted area of 9p by multiplex PCR-LOH analysis. Thus, several putative chromosomal changes were preferentially present in malignant GISTs but rare in benign and borderline GISTs. These findings suggest that accumulated chromosomal changes may contribute to the progression and/or malignant transformation of GISTs.

Putative chromosomal deletions on 9P, 9Q and 22Q occur preferentially in malignant gastrointestinal stromal tumors

To characterize the type of genetic alterations in gastrointestinal stromal tumors (GISTs), we performed a comprehensive allelotype study of 14 GISTs (2 benign, 7 borderline and 5 malignant) by polymerase-chain-reaction and loss-of-heterozygosity (PCR-LOH) analysis using 102 microsatellite markers, and compared the results with comparative-genomic-hybridization (CGH) analysis. Among the 38 evaluated chromosomal arms, 16 (42.1%) showed LOH in at least one patient. Most frequent LOH was observed at chromosome 14p and 14q (9/14, 64%) and this was demonstrated in all types of GISTs (50% in benign, 71% in borderline and 80% in malignant). Additional chromosomal deletions were found in several chromosomal arms. Among them, deletions on chromosomal arms of 22q (3/14, 21.4%), 9p (2/14, 14.3%) and 9q (2/14, 14.3%) were the most frequent, and were detected only in malignant GISTs both by PCR-LOH and by CGH analysis. Additionally, 2 malignant GISTs with LOH on 9p showed homozygous deletions in the restricted area of 9p by multiplex PCR-LOH analysis. Thus, several putative chromosomal changes were preferentially present in malignant GISTs but rare in benign and borderline GISTs. These findings suggest that accumulated chromosomal changes may contribute to the progression and/or malignant transformation of GISTs.

Recurrence following curative resection for gastric carcinoma

BACKGROUND

The diagnosis and treatment of recurrent gastric cancer remains difficult. The aim of this study was to determine the risk factors for recurrence of gastric cancer and the prognosis for these patients.

METHODS

Of 2328 patients who underwent curative resection for gastric cancer from 1987 to 1995, 508 whose recurrence was confirmed by clinical examination or reoperation were studied retrospectively. The risk factors that determined the recurrence patterns and timing were investigated by univariate and multivariate analysis.

RESULTS

The mean time to recurrence was 21.8 months and peritoneal recurrence was the most frequent (45.9 per cent). Logistic regression analysis showed that serosal invasion and lymph node metastasis were risk factors for all recurrence patterns and early recurrence (at 24 months or less). In addition, independent risk factors involved in each recurrence pattern included younger age, infiltrative or diffuse type, undifferentiated tumour and total gastrectomy for peritoneal recurrence; older age and larger tumour size for disseminated, haematogenous recurrence; and older age, larger tumour size, infiltrative or diffuse type, proximally located tumour and subtotal gastrectomy for locoregional recurrence. Other risk factors for early recurrence were infiltrative or diffuse type and total gastrectomy. Reoperation for cure was possible in only 19 patients and the mean survival time after conservative treatment or palliative operation was less than 12 months.

CONCLUSION

The risk factors for each recurrence pattern and timing of gastric cancer can be predicted by the clinicopathological features of the primary tumour. Since the results of treatment remain dismal, studies of perioperative adjuvant therapy in an attempt to reduce recurrence are warranted.

Clinical characteristics of Peutz-Jeghers syndrome in Korean polyposis patients

Peutz-Jeghers syndrome is an autosomal dominant inherited disorder characterized by hamartomatous polyps in the small bowel and mucocutaneous pigmentation. Patients with Peutz-Jeghers syndrome often present as surgical emergencies with complications of the polyps, such as intussusception, bowel obstruction, and bleeding. Recently an increased risk of malignancies has also been reported. This study was initiated to determine the clinical features of Peutz-Jeghers syndrome in Korean patients, with special attention to the development of malignancies. Thirty patients with Peutz-Jeghers syndrome were investigated; their median age was 23.5 years, and symptoms appeared at a median age of 12.5 years. Family history was positive in one-half of cases, and mucocutaneous pigmentation was observed in almost all patients (93%). The jejunoileum was the most frequent site of the polyps, and there were generally 10-100 polyps. Multiple laparotomies were performed in a substantial portion of the patients, due mainly to polyp-induced bowel obstruction, and the surgical interventions were begun at a relatively young age (average 21.4 years). Four cases of small-bowel cancer and one case of breast cancer were detected in probands, at a relatively young age (mean 36 years). Cancers of the small bowel, stomach, colon, breast and cervix were diagnosed in the first relatives of the probands. Close follow-up from an early age should thus be performed in patients with Peutz-Jeghers syndrome as they are at high risk of surgical emergency and development of malignancy.

Assessment of biomarkers in paired primary and recurrent colorectal adenocarcinomas

PURPOSE

Recurrent colorectal cancers respond poorly to anticancer treatment including radiotherapy. To better understand the biological characteristics of the recurrent colorectal tumor, we investigated various biomarkers regulating cell proliferation and cell loss in paired primary and recurrent colorectal tumor specimens within each individual.

METHODS AND MATERIALS

From a total of 11 colorectal adenocarcinoma patients, 22 specimens of paired primary and recurrent tumors were obtained for analysis. Apoptosis was evaluated by TUNEL labeling of apoptotic DNA fragmentation. Other biomarkers including proliferating cell nuclear antigen (PCNA), p53, WAF1, p34cdc2, and cyclins B1 and D1 were analyzed by immunohistochemical stains.

RESULTS

PCNA index (PCNAI) showed an increase in 6 and a decrease in 5 recurrent tumors compared to primary tumors. Median PCNAI in primary and recurrent tumors were 33.5 and 48.3, respectively (p = 0.16). In contrast, the apoptotic index (AI) decreased in 9 of 11 recurrent tumors compared to primary tumors. Median AI decreased from 4.3 in primary tumors to 1.4 in recurrent tumors (p = 0.04). The p53 expression increased in more than half of recurrent tumors compared to primary tumors. Mean staining score increased from 0.7 in primary tumors to 1.2 in recurrent tumors (p = 0.059). WAF1 and cyclin B1 did not show significant change. In contrast, both cyclin D1 and p34cdc2 increased significantly in recurrent tumors. These two biomarkers showed increased expression in 8 (cyclin D1) and 7 (p34cdc2) recurrent tumors, respectively, compared to their primary counterparts. Mean staining scores of both biomarkers in recurrent tumors increased by more than twofold compared to those in primary tumors and these differences were statistically significant (cyclin D1, p = 0.007; p34cdc2, p = 0.008).

CONCLUSION

This study showed significantly decreased apoptosis in recurrent colorectal tumors compared to their primary counterparts. The underlying regulatory mechanisms included increased expression of p53 and altered cell cycle regulators such as increased cyclin D1 and p34cdc2. With further study, it may be used for developing a new therapeutic strategy for the treatment of recurrent colorectal cancer.

Changes of telomerase and telomere lengths in paired normal and cancer tissues of breast

To attain the immortal phenotype, cancer cells must overcome the mitotic clock. Telomerase activity has been identified to be activated in malignant tumors including breast cancer. Telomerase activity was evaluated in 71 breast cancer tissues and paired normal tissues with the TRAP (telomerase repeat amplification protocol) assay. Telomerase activity was calculated and translated into arbitrary units by computer-assisted densitometry with the control of telomerase activity in the 293 control cell line. In 59 paired breast tissues with telomerase activity, terminal restriction fragment (TRF) lengths were measured using Southern blotting. Relative inhibition (RI), the ratio of inhibited telomerase activity in each tumor tissue compared to that of the 293 control cell line after pre-treatment with 150 microg/ml of RNAse A, was measured. Sixty-three of 71 cancer tissues showed telomerase activity (88.7%) with 75.3+/-17.9 units in densitometry, while no telomerase activity was detected in their paired normal tissues. Telomerase activity was correlated to node metastasis (p=0.02) and stage (p=0.005), but not to tumor size or the hormonal receptor status. TRF lengths were 11. 0+/-4.7 kb in 59 tumor tissues and 11.7+/-2.2 kb in paired normal tissues. TRF lengths did not correlate to any of the clinical parameters. However changes of TRF lengths in tumor tissues compared to those of normal tissues correlated to telomerase activity. RI in the tumor tissues was proportional to telomerase activity without RNAse A pre-treatment. In breast cancer, telomerase activity was specific to tumor tissues and increased with tumor progression. Telomerase activity and changes in TRF lengths can be used as guidelines in detecting candidates for the telomerase inhibitor.

Modulation of biological phenotypes for tumor growth and metastasis by target-specific biological inhibitors in gastric cancer

For tumor progression, a cascade of linked sequential biological events is essential. We tried to test whether biological therapy can modulate specific biological phenotypes and increase the anti-tumor effect when combined with chemotherapy. Five human gastric cancer cell lines (YCC-1, YCC-2, YCC-3, YCC-7, AGS) were used in these studies. Pentosan polysulfate (PPS) as a heparin-binding growth factor inhibitor, Tranexamic acid as a plasmin inhibitor, Lovastatin as an adhesion inhibitor and Adriamycin as a chemotherapeutic agent were selected. The effects of each drug on colony formation and tumor cell proliferation were evaluated by soft agar assay and cell proliferation assay, respectively to test direct anti-tumor effect. The expression of uPA, PAI-1 was determined by ELISA, while MMPs activity was evaluated by zymography. PPS suppressed the colony-forming activity as much as Adriamycin did, but it showed only cytostatic effects in cell proliferation assay. Migration capacity using Boyden chamber assay was more closely correlated with adhesive capacity than uPA or MMP-2 expression. The motility inhibitory effect of Tranexamic acid was observed in the YCC-7 cell line, which expressed all the required biological phenotypes for migration. In AGS, with high cell motility and adhesiveness, the adhesion was inhibited by Lovastatin and most of the inhibitory effect was recovered by Mevalonate. When PPS was combined with Adriamycin on the Adriamycin-resistant, midkine (MK) gene expressing YCC-7 cell line, the growth inhibition rate increased up to 84%, while that for a single treatment of PPS or Adriamycin was 40% and 22%, respectively (p=0.001). When we combined Tranexamic acid and Adriamycin, we observed the synergistic effect in YCC-3 and YCC-7, while no combined effect was found in YCC-1. The combination of Lovastatin and Adriamycin did not show any combined effects in any of the cell lines. In conclusion, a synergistic anti-proliferative effect (chemo-sensitization) with combined chemo-biotherapy was found in cancer cells with specific biological target, MK. The anti-motility effect was the greatest when the gastric cancer cells expressed all the specific biological phenotypes.

Prognostic significance of CD44 and nm23 expression in patients with stage II and stage IIIA gastric carcinoma

BACKGROUND AND OBJECTIVES

Predicting the prognosis in gastric carcinoma patients with intermediate stages is difficult. We investigated the prognostic impacts of CD44 and nm23 expression in a homogeneous group of patients with stage II and IIIA gastric carcinoma who had undergone curative resections.

METHODS

A total of 261 paraffin-embedded gastric carcinomas were stained with the monoclonal antibodies CD44 and nm23 using the labeled streptovidin biotin method.

RESULTS

The expression of CD44 and nm23 was detected, respectively, in 31.0% (81/261) and 70.1% (183/261) of all tumors. There was no correlation between CD44 expression and clinicopathological variables. However, nm23 was more frequently expressed in older patients with differentiated adenocarcinoma. A significant difference in 5-year survival rates was found between patients with CD44-positive (43.2%) and CD44-negative tumors (63.4%), (P = 0.0018). However, there was no significant difference in 5-year survival rates between patients with nm23-positive (54.7%) and nm23-negative tumors (62.7%) (P = 0.2734).

CONCLUSIONS

CD44 expression was a significant adverse prognostic factor in gastric carcinoma and may be a predictor of metastatic potential of the primary tumor. By contrast, immunohistochemical detection of nm23 expression was not a predictor of outcome of patients with gastric carcinoma.

Comparative study of transrectal ultrasonography, pelvic computerized tomography, and magnetic resonance imaging in preoperative staging of rectal cancer

PURPOSE

The preoperative assessment of rectal cancer wall invasion and regional lymph node metastasis is essential for the planning of optimal therapy. This study was done to determine the accuracy and clinical usefulness of transrectal ultrasonography, pelvic computed tomography, and magnetic resonance imaging in preoperative staging.

METHODS

A total of 89 patients with rectal cancer were examined with transrectal ultrasonography (n = 89), pelvic computed tomography (n = 69), and magnetic resonance imaging with endorectal coil (n = 73). The results obtained by these diagnostic modalities were compared with the histopathologic staging of specimens.

RESULTS

In staging depth of invasion, the overall accuracy was 81.1 percent (72/89) by transrectal ultrasonography, 65.2 percent (45/ 69) by computed tomography, and 81 percent (59/73) by magnetic resonance imaging. Overstaging was 10 percent (9/89) by transrectal ultrasonography, 17.4 percent (12/69) by computed tomography, and 11 percent (8/73) by magnetic resonance imaging; and understaging was 8 of 89 (8.9 percent) by transrectal ultrasonography, 12 of 69 (17.4 percent) by computed tomography, and 6 of 73 (8 percent) by magnetic resonance imaging. In staging lymph node metastasis, the overall accuracy rate was 54 of 85 (63.5 percent) in transrectal ultrasonography, 39 of 69 (56.5 percent) in computed tomography, and 46 of 73 (63 percent) in magnetic resonance imaging. The sensitivity was 24 of 45 (53.3 percent) in transrectal ultrasonography, 14 of 25 (56 percent) in computed tomography, and 33 of 42 (78.5 percent) in magnetic resonance imaging; and specificity was 30 of 40 (75.0 percent) in transrectal ultrasonography, 25 of 44 (56.8 percent) in computed tomography, and 13 of 31 (41.9 percent) in magnetic resonance imaging. The accuracy in detection of positive lateral pelvic lymph nodes under magnetic resonance imaging (n = 8) was 12.5 percent. The accuracy in detection of posterior vaginal wall invasion was 100 percent in transrectal ultrasonography (n = 7) and 100 percent in magnetic resonance imaging (n = 3), but 28.5 percent in computed tomography (n = 7).

CONCLUSIONS

Both transrectal ultrasonography and magnetic resonance imaging with endorectal coil exhibited similar accuracy and were superior to conventional computed tomography in preoperative assessment of depth of invasion and adjacent organ invasion. Because transrectal ultrasonography is a safer and more cost-effective modality than magnetic resonance imaging, transrectal ultrasonography is an appropriate method for preoperative staging of rectal cancer. Further efforts will be needed to provide a better staging of lymph node involvement.

Prognostic significance of CD44 and nm23 expression in patients with stage II and stage IIIA gastric carcinoma

BACKGROUND AND OBJECTIVES

Predicting the prognosis in gastric carcinoma patients with intermediate stages is difficult. We investigated the prognostic impacts of CD44 and nm23 expression in a homogeneous group of patients with stage II and IIIA gastric carcinoma who had undergone curative resections.

METHODS

A total of 261 paraffin-embedded gastric carcinomas were stained with the monoclonal antibodies CD44 and nm23 using the labeled streptovidin biotin method.

RESULTS

The expression of CD44 and nm23 was detected, respectively, in 31.0% (81/261) and 70.1% (183/261) of all tumors. There was no correlation between CD44 expression and clinicopathological variables. However, nm23 was more frequently expressed in older patients with differentiated adenocarcinoma. A significant difference in 5-year survival rates was found between patients with CD44-positive (43.2%) and CD44-negative tumors (63.4%), (P = 0.0018). However, there was no significant difference in 5-year survival rates between patients with nm23-positive (54.7%) and nm23-negative tumors (62.7%) (P = 0.2734).

CONCLUSIONS

CD44 expression was a significant adverse prognostic factor in gastric carcinoma and may be a predictor of metastatic potential of the primary tumor. By contrast, immunohistochemical detection of nm23 expression was not a predictor of outcome of patients with gastric carcinoma.

Comparison of prognostic significance of nodal staging between old (4th edition) and new (5th edition) UICC TNM classification for gastric carcinoma. International Union Against Cancer

The description of nodal staging for gastric cancer was changed in the new fifth edition of the International Union Against Cancer (UICC) TNM classification from the anatomic sites of metastatic lymph nodes to the number of metastatic lymph nodes, as pN1 is metastasis in 1 to 6 lymph nodes, pN2 is in 7 to 15 lymph nodes, and pN3 is in 16 or more lymph nodes. The purpose of this study was to investigate the prognostic significance of the new staging system based on the number of metastatic lymph nodes compared to the old staging system by anatomic site. From 1987 to 1994 a total of 2108 patients who underwent potentially curative resections with D2 or D3 lymph node dissection and with 15 or more lymph nodes retrieved were studied retrospectively. Lymph node metastases were found in 1018 patients (48.3%). A mean of 37.9 lymph nodes were retrieved per patient, and a mean of 7.2 lymph nodes were invaded by tumor cells. We found that the new nodal staging based on the number of metastatic lymph nodes closely correlated with the depth of cancer invasion and with the old nodal staging based on the anatomic site of the metastatic nodes, with statistical significance. The 5-year survival rates after gastrectomy decreased significantly by increasing the extent of the pN classification in both nodal staging methods. In a subgroup analysis of survivals between the old and new nodal staging, the new classification showed more homogeneous survival at the same stage than the old one. With a multivariate analysis of prognostic factors, including the old and new nodal staging, the depth of invasion and the new nodal stage were the most significant prognostic factors, followed by the old nodal stage. Our data suggested that the new nodal staging based on the number of metastatic lymph nodes is not only a reliable and objective method for nodal classification, but it is also a significant prognostic determinant for gastric cancer that can be used in practice.

Clinicopathologic characteristics of mucinous gastric adenocarcinoma

There has been considerable controversy over the prognosis of mucinous gastric adenocarcinoma (MGC). In this study we analyzed the clinicopathologic differences between MGC and non-mucinous gastric carcinoma (NMGC). In addition, the relationship between mucin content and other clinicopathologic variables, including prognosis in MGC, was also investigated. We reviewed 2118 patients with pathologically-confirmed gastric cancer who underwent gastrectomy at the Department of Surgery, Yonsei University College of Medicine, during the period between Jan. 1987 and Dec. 1993. Among them, 130 patients had gastric carcinoma with extracellular mucin (MGC) and 1988 patients had gastric carcinoma without extracellular mucin (NMGC). We placed the MGC patients into two groups according to mucin content: mucin content involving over 50% of the tumor (dominant type, n = 94) and mucin content involving less than 50% of the tumor area (partial type, n = 36). The results were as follows: MGC was more common in males than NMGC. The size of the tumor in MGC (mean 5.3 cm) was larger than that of NMGC (mean 4.4 cm). The patients with MGC had a higher incidence of Borrmann type IV (MGC: 16.1%, NMGC: 9.9%), more frequent serosal invasion (MGC: 75.4%, NMGC: 48.6%), lymph-node metastasis (MGC: 75.4%, NMGC: 50.7%), and peritoneal metastasis (MGC: 10.0%, NMGC: 3.5%) than patients with NMGC. The patients with MGC were more advanced in stage at the time of diagnosis and had a worse overall 10-year survival rate (44.9%) than patients with NMGC (54.7%). However, the 10-year survival rate according to the stage of MGC was similar to that of NMGC. There were no significant differences between the mucin content and other pathologic variables, including prognosis, i.e. similar biologic behavior between dominant type MGC and partial type MGC. In conclusion, we suggest that MGC was more frequently diagnosed in advanced stage than NMGC with a poorer prognosis and that it is reasonable to consider the carcinoma with mucin content involving more than 30% of the tumor area as MGC.