Two distinct pathways of tumorigenesis of adenocarcinomas of the esophagogastric junction, related or unrelated to intestinal metaplasia

It is still uncertain whether intestinal metaplasia (IM) of the esophagogastric junction (EGJ) plays a role in the development of adenocarcinoma of the esophagogastric junction (AEGJ). The purpose of the present study was to clarify the relationship between AEGJ and IM in Japanese patients. Forty-eight AEGJ, <3 cm and centered within 1 cm of the EGJ, were investigated. The frequency of IM around AEGJ and the correlation between IM and clinicopathological features were examined. IM was present in the surrounding mucosa in 22 of 48 cases (46%), and was seen more frequently in older patients (P = 0.008). Lymph node metastasis was observed only in cases in which the tumors were not associated with IM (P = 0.017). The gastric phenotype was seen almost exclusively in the group without IM, while the intestinal phenotype was predominant in the group with IM (P = 0.003). The present study found a lower incidence of associated IM than Western studies, and there were significant differences in clinicopathological features between AEGJ with and without IM. It is suggested that AEGJ may develop via two distinct pathways in Japanese patients: IM-related and IM-unrelated.

Establishment of a tetraploid cell line from mouse H-1 (ES) cells highly polyploidized with demecolcine

OBJECTIVE

Establishment of tetraploid ES cells.

MATERIALS AND METHODS

Mouse H-1 (ES) cells were polyploidized by demecolcine and released from the drug.

RESULTS

A tetraploid cell line (4nH1 cells) was established from mouse H-1 (ES) cells (2nH1 cells) highly polyploidized by treatment with demecolcine. Cell cycle parameters of 4nH1 cells were almost the same as those of 2nH1 cells, suggesting that the rate of DNA synthesis was about twice that of the diploid cells. Mode of chromosome number of 4nH1 cells was 76, about twice that of 2nH1 cells. Cell volume of 4nH1 cells was about twice of that of diploid cells, indicating that 4nH1 cells contained about twice as much total intracellular material as 2nH1 cells. Morphology of the 4nH1 cells was flagstone-like, thus differing from that of the spindle-shaped 2nH1 cells, suggesting that the transformation had occurred during the diploid-tetraploid transition. 4nH1 cells exhibited alkaline phosphatase activity and formed teratocarcinomas, implying that they would be pluripotent.

CONCLUSION

A pluripotent tetraploid cell line (4nH1 cells) was established.

Flt3 ligand promotes myeloid dendritic cell differentiation of human hematopoietic progenitor cells: possible application for cancer immunotherapy

Current in vitro culture systems allow the generation of human dendritic progenitor cells (CFU-DCs). The aim of this study was to assess the effect of Flt3 ligand (FL) on the proliferation of human peripheral blood-derived myeloid CFU-DCs and their differentiation into more committed precursor cells (pDCs) using in vitro culture systems. Immunomagnetically separated CD34+ cells were cultured in serum-free, as well as in serum-containing, liquid suspension cultures to investigate the expansion and/or proliferation/differentiation of CFU-DCs, pDCs, and more mature dendritic cells (DCs). FACS-sorted CD34+Flt3+/- cells were cultured in methylcellulose to assay hematopoietic progenitors, including CFU-DCs. In the clonal cell culture supplemented with granulocyte/macrophage (GM) colony-stimulating factor (CSF), interleukin-4, and tumor necrosis factor alpha, the frequency of CFU-DCs was significantly higher in the CD34+Flt3+ fraction than in the CD34+Flt3- population, thus suggesting functional Flt3 expression on CFU-DCs. Serum-free suspension culture of CD34+ cells revealed the potent effect of FL on the expansion of CFU-DCs in synergy with GM-CSF and thrombopoietin (TPO). In addition, FL strongly induced the maturation of CFU-DCs into functional CD1a+ pDCs in serum-containing liquid suspension culture. Moreover, these FL-generated pDCs showed remarkable potential to differentiate into mature DCs with surface CD83/CD86 expression, which induced a distinct allogeneic T-cell response. These results clearly demonstrate that FL supports not only the proliferation of early hematopoietic progenitor cells, but also the maturation process of committed precursor cells along with the DC-lineage differentiation. Therefore, it is possible to develop a more efficient DC-based cancer immunotherapy using this specific cytokine combination, GM-CSF+TPO+FL in vitro in the near future.

Results of repeated hepatectomy for recurrent hepatocellular carcinoma

BACKGROUND/AIMS

The long-term outcome of patients undergoing repeated hepatectomy for secondary hepatocellular carcinoma (HCC) were investigated to assess the selection criteria for, and efficacy of, repeated hepatectomy.

METHODOLOGY

21 patients with secondary HCC who had undergone repeated hepatectomy (R group) were analyzed. Clinical characteristics, histopathologic findings and postoperative clinical course were compared for patients with primary and secondary HCCs in the R group. The risk factors for post repeated hepatectomy survival and disease-free survival were estimated for the R group.

RESULTS

There were no significant differences in patient characteristics or histologic features of primary and secondary HCCs in the R group. A significant difference in cumulative postoperative disease-free survival was not seen for primary and secondary HCCs, average duration was 39.4 and 21.3 months. Liver cirrhosis and narrow hepatectomy (subsegmentectomy, limited resection and enucleation) were found to be significant risk factors of survival after secondary hepatectomy. The 5-year post-recurrence survival rate of nine patients in the R group who had two risk factors was 14.8%.

CONCLUSIONS

In cirrhotic patients with secondary HCC, inadequate narrow repeated hepatic resection should not receive repeated hepatectomy.

Prognostic and Clinical Evaluation of Axillary Lymph Node Metastasis in Esophageal Cancer

Axillary lymph node metastasis (ALNM) from esophageal cancer is rare. Its prognosis and effective treatments remain unknown. Between 1997 and 2005, esophagectomy was performed in 361 patients with esophageal cancer in our hospital. ALNM was identified in four patients (1.1%). All patients had left ALNM with ipsilateral left supraclavicular lymph node metastasis. In two patients ALNM developed after radical esophagectomy with regional lymphadenectomy and in the other two patients after chemoradiotherapy of primary lesions. Axillary lymphadenectomy with chemoradiotherapy was given to all patients. Median survival time and disease-free survival (DFS) after initial treatment for primary esophageal cancer were 30.5 months and 11.5 months, respectively. One patient, who had a small number of regional lymph node metastases (two lymph nodes) at esophagectomy and prolonged DFS (22 months) until axillary node recurrence, is still alive, 67 months after axillary lymphadenectomy. The other three patients, who had larger numbers of regional lymph node metastases (average, 8.3) and shorter DFS (average, 9.7 months), died of recurrence an average of 13.3 months after axillary lymphadenectomy. In conclusion, although ALNM is considered a type of distant organ metastasis, if it is a solitary recurrence, good survival may be obtained after appropriate loco-regional therapy. The number of metastatic regional lymph nodes at initial esophagectomy and the duration of DFS until axillary node recurrence can help to guide the decision whether aggressive treatments are warranted.

Clinical application of methylation specific-polymerase chain reaction in serum of patients with gastric cancer

BACKGROUND/AIMS

We previously reported that aberrant methylation of p16 and/or E-cadherin genes in serum DNA could serve together as a tumor marker in gastric cancer. We presently investigated whether sensitivity could be increased by consideration of a third gene, which encodes retinoic acid receptor-1 (RARbeta).

METHODOLOGY

We performed a methylation-specific polymerase chain reaction (MSP) in serum DNA to detect aberrant methylation of RARbeta from 109 preoperative gastric cancer patients, in which the first two genes had been characterized. We also examined all three genes in sera from 10 outpatients during postgastrectomy follow-up.

RESULTS

Aberrant methylation of RARbeta was demonstrated in 26 preoperative patients (24%). Considering this with previous results, 52 patients (48%) of the 109 preoperative showed hypermethylation of at least one gene (p16, E-cadherin, and/or RARbeta). No aberrant methylation was detected in control sera. In the follow-up group, aberrant methylation was demonstrated in 2 of the 3 patients who had definite radiologic evidence of recurrences. One of the patients showing promoter hypermethylation without definite findings of recurrence at the time of analysis developed peritoneal recurrence 6 months later.

CONCLUSIONS

Including the MSP assay in conventional follow-up could facilitate early detection of recurrent disease in gastric cancer patients.

Frequent silencing of RUNX3 in esophageal squamous cell carcinomas is associated with radioresistance and poor prognosis

Radiotherapy is an effective treatment for some esophageal cancers, but the molecular mechanisms of radiosensitivity remain unknown. RUNX3, a novel tumor suppressor of gastric cancer, functions in transforming growth factor (TGF)-beta-dependent apoptosis. We obtained paired samples from 62 patients with advanced esophageal cancers diagnosed initially as T3 or T4 with image diagnosis; one sample was obtained from a biopsy before presurgical radiotherapy, and the other was resected in surgical specimens after radiotherapy. RUNX3 was repressed in 67.7% cases of the pretreatment biopsy samples and 96.7% cases of the irradiated, resected samples. The nuclear expression of RUNX3 was associated with radiosensitivity and a better prognosis than cytoplasmic or no RUNX3 expression (P<0.003); cytoplasmic RUNX3 expression was strictly associated with radioresistance. RUNX3 was downregulated and its promoter was hypermethylated in all radioresistant esophageal cancer cell lines examined. Stable transfection of esophageal cancer cells with RUNX3 slightly inhibited cell proliferation in vitro, enhanced the antiproliferative and apoptotic effects of TGF-beta and increased radiosensitivity in conjunction with Bim induction. In contrast, transfection of RUNX3-expressing cells with a RUNX3 antisense construct or a Bim-specific small interfering RNA induced radioresistance. Treatment with 5-aza-2'-deoxycytidine restored RUNX3 expression, increased radiosensitivity and induced Bim in both control and radioresistant cells. These results suggest that RUNX3 silencing promotes radioresistance in esophageal cancers. Examination of RUNX3 expression in pretreatment specimens may predict radiosensitivity, and induction of RUNX3 expression may increase tumor radiosensitivity.

Effects of genetic backgrounds on hyperbilirubinemia in radixin-deficient mice due to different expression levels of Mrp3

ERM (ezrin/radixin/moesin) proteins are organizers of apical actin cortical layer in general. We previously reported that the knockout of radixin resulted in Rdx(-/-) mice with displacement/loss of the canalicular transporter Mrp2, giving rise to Dubin-Johnson syndrome-like conjugated hyperbilirubinemia in the mixed genetic background (C57BL/6-129/Sv) (Kikuchi, et al. (2002) Nature Genetics 31, 320-325). However, when these mice were kept under mixed genetic background for years (late mixed backgrounds; LMB), the conjugated hyperbilirubinemia gradually became inconspicuous, while evidence of liver injury increased. We examined the effect of genetic background by backcrossing LMB Rdx(-/-) mice to C57BL/6 and 129/Sv wild type mice with the result that the Rdx(-/-) congenic mice regained hyperbilirubinemia with reduced hepatocellular damage. As revealed by immunofluorescence and western blots, the localization/expression of apical transporters, Mrp2, CD26, P-gps, and Bsep were not influenced by backcrossing, though those of a basolateral transporter, Mrp3, were strikingly increased by backcrossing.

Prediction of lymph node metastasis by size of early gastric carcinoma

BACKGROUND/AIMS

Tumor size requires more investigation as a factor in determining extent of regional lymph node dissection in early gastric carcinoma. We retrospectively investigated 573 patients with such tumors to identify predictors of lymph node metastasis.

METHODOLOGY

Postoperative survival was examined for groups of patients defined by tumor size under 2 cm, between 2 and 4cm, and over than 4cm. Factors predicting tumor recurrence and regional lymph node metastasis also were determined.

RESULTS

Postoperative survival of patients with tumors larger than 4 cm was significantly worsethan that of patients with tumors smaller than 2 cm. Multivariate analysis identified lymph node metastasis as a significant risk factor for recurrence of early gastric carcinoma, while identifying primary tumor size and lymphatic vessel involvement as significant risk factors for lymph node metastasis.

CONCLUSIONS

Lymph node metastasis, which increased risk of postoperative recurrence in early gastric carcinoma, was related to tumor size.

Fenretinide up-regulates DR5/TRAIL-R2 expression via the induction of the transcription factor CHOP and combined treatment with fenretinide and TRAIL induces synergistic apoptosis in colon cancer cell lines

Fenretinide (N-[4-Hydroxyphenyl]retinamide; 4HPR) is a semisynthetic retinoid that induces apoptosis in a variety of malignancies. Fenretinide has been examined in clinical trials as a cancer chemopreventive and chemotherapeutic agent. Oxidative stress induced by fenretinide has been shown to mediate apoptosis through a mitochondrial pathway by the induction of a transcription factor CCAAT/enhancer binding protein homologous protein (CHOP) and Bak. In this study, we report that fenretinide induces death receptor 5 (DR5)/TRAIL-R2 up-regulation via the induction of the transcription factor CHOP in colon cancer cell lines. Fenretinide induced DR5 expression at protein and mRNA levels. Furthermore, fenretinide increased DR5 promoter activity and the enhanced activity decreased by mutation of the CHOP binding site. CHOP was also up-regulated by fenretinide at the promoter level. We also showed that combined treatment with fenretinide and TRAIL induced synergistic apoptosis in colon cancer cell lines. The synergistic apoptosis was markedly blocked by DR5/Fc chimeric protein. Fenretinide and TRAIL cooperatively activated caspase-3, -8, -10 and -9 and cleavage of Bid and PARP, and this activation was also blocked in the presence of DR5/Fc chimeric protein. These results indicate that fenretinide-induced apoptosis is sensitized by TRAIL. Therefore, combined treatment with fenretinide and TRAIL might be a promising model for the treatment of colorectal cancer.

Circulating cell-free mRNA in plasma as a tumor marker for patients with primary and recurrent gastric cancer

BACKGROUND

The diagnostic value of circulating mRNA for the early detection of primary and recurrent gastric cancer was evaluated.

PATIENTS AND METHODS

Circulating hTERT and MUC1 mRNA were amplified in the plasma from 52 gastric cancer patients (40 preoperative and 12 postoperative patients) and 20 healthy controls. The results were compared with those of a circulating cancer cell assay and methylation-specific polymerase chain reaction assay.

RESULTS

Cell-free mRNA of the analyzed genes was detected in 6 (15%) preoperative gastric cancer patients (hTERT: 3 and MUC1: 4 patients) and 2 follow-up patients. These mRNAs were not detected in the plasma from healthy volunteers. There was no correlation between the results of the cell-free mRNA and the other assays.

CONCLUSION

Detection of circulating cell-free mRNA might serve as a new complementary tumor marker for gastric cancer.

Successful induction of clinically competent dendritic cells from granulocyte colony-stimulating factor-mobilized monocytes for cancer vaccine therapy

Recent studies have suggested that dendritic cell (DC)-based immunotherapy is one promising approach for the treatment of cancer. We previously studied the clinical toxicity, feasibility, and efficacy of cancer vaccine therapy with peptide-pulsed DCs. In that study, we used granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood monocytes as a cell source of DCs. However, previous investigations have suggested that G-CSF-mobilized peripheral blood monocytes produce reduced levels of proinflammatory cytokines such as interleukin (IL)-12 and tumor necrosis factor (TNF)-alpha. These T helper (Th)-1-type cytokines are thought to promote antitumor immune response. In this study, we assessed the functional abilities of DCs generated from G-CSF-mobilized monocytes obtained from 13 patients with CEA-positive advanced solid cancers. Peripheral blood mononuclear cells were obtained from leukapheresis products collected before and after systemic administration of G-CSF (subcutaneous administration of high-dose [5-10 microg/kg] human recombinant G-CSF for five consecutive days). In vitro cytokine production profiles after stimulation with lipopolysaccharide (LPS) were compared between monocytes with and without G-CSF mobilization. DCs generated from monocytes were also examined with respect to cytokine production and the capacity to induce peptide-specific T cell responses. Administration of G-CSF was found to efficiently mobilize peripheral blood monocytes. Although G-CSF-mobilized monocytes (G/Mo) less effectively produced Th-1-type cytokines than control monocytes (C/Mo), DCs generated from G/Mo restored the same level of IL-12 production as that seen in DCs generated from C/Mo. T cell induction assay using recall antigen peptide and phenotypic analyses also demonstrated that DCs generated from G/Mo retained characteristics identical to those generated from C/Mo. Our results suggest that G-CSF mobilization can be used to collect monocytes as a cell source for the generation of DCs for cancer immunotherapy. DCs generated in this fashion were pulsed with HLA-A24-restricted CEA epitope peptide and administered to patients safely; immunological responses were induced in some patients.

Induction of mitochondria-dependent apoptosis through the inhibition of mevalonate pathway in human breast cancer cells by YM529, a new third generation bisphosphonate

YM529, a new third generation bisphosphonate, induced apoptosis of a human breast cancer cell line, MX-1. Cytotoxic activity of YM529 was more potent than that of incadronate. YM529 activated caspase-9, but not caspase-8, and induced the release of cytochrome c into cytosol. YM529 increased Bax expression and decreased Bcl-2 expression, while it did not induce caspase-8-dependent Bid truncation. Farnesyl pyrophosphate prevented YM529-mediated cytotoxicity. These results suggest that YM529 is a potent therapeutic agent for human breast cancers, activating the mitochondria-dependent apoptotic pathway through the inhibition of protein farnesylation.

Induction of peptide-specific immune response in patients with primary malignant melanoma of the esophagus after immunotherapy using dendritic cells pulsed with MAGE peptides

Primary malignant melanoma of the esophagus (PMME) is a very rare disease with an extremely poor prognosis. Surgery is currently considered its best treatment, while any other measures are ineffective. We studied the effect of active specific immunotherapy using monocyte-derived dendritic cells (DCs) pulsed with the epitope peptides of melanoma-associated antigens (MAGE-1, MAGE-3) in patients with PMME after surgery, for the first time. The patient received passive immunotherapy with lymphokine-activated killer cells concomitantly. Two HLA-A24-positive patients with PMME were treated. Both patients initially received radical esophagectomy with regional lymphadenectomy, followed by adjuvant chemotherapy with dacarbazine, nimustine, vincristine and interferon-alpha. In the case 1 patient, active specific immunotherapy was used to treat a large abdominal lymph node metastasis that became obvious 21 months after surgery. The disease remained stable for 5 months, and the patient survived for 12 months after the initiation of immunotherapy. In the case 2 patient, immunotherapy was tried as post-operative adjuvant treatment after adjuvant chemotherapy. There was no tumor recurrence for 16 months after the immunotherapy. As of 49 months after esophagectomy, the patient is still alive. In both patients, the ability of peripheral lymphocytes to produce IFN-gamma in vitro in response to peptide stimulation was significantly enhanced and delayed-type hypersensitivity skin test response to MAGE-3 peptide was turned positive after immunotherapy. In conclusion, active specific immunotherapy for PMME with the use of DCs and MAGE peptides was safe and capable of inducing peptide-specific immune responses. This case report warrants further clinical evaluation of this immunotherapy for PMME.

Circulating tumor cells and aberrant methylation as tumor markers in patients with esophageal cancer

BACKGROUND

This study was designed to compare the detection rates of conventional tumor markers with two molecular diagnostic approaches on blood samples from patients with esophageal squamous cell cancer.

MATERIALS AND METHODS

Preoperative blood samples were obtained from 44 esophageal cancer patients and were subjected to CEA-specific reverse transcriptase-polymerase chain reaction (RT-PCR) assay and methylation-specific polymerase chain reaction (MSP) assay for p16, E-cadherin and RARbeta genes.

RESULTS

Circulating tumor cells were detected in 12 patients (27%); 14 patients (32%) had aberrant methylation in the promoter region of at least one gene (6, 4 and 4 patients, for p16, E-cadherin and RARbeta, respectively). No abnormality was detected by either assay in control plasmas. Altogether, 23 patients (53%) had a positive result in either molecular assay. There was no correlation between either assay result and those of conventional serum markers.

CONCLUSION

The RT-PCR and MSP assays can serve as complementary markers for screening and monitoring esophageal cancer patients.

Endocrine Cell and Nerve Regeneration in Autologous In Situ Tissue-Engineered Small Intestine

BACKGROUND

The purpose of this study was to regenerate a larger size of small intestinal tissue than that of our previous study and to evaluate the regeneration of the endocrine cells (ECC) and nerve system of autologous tissue-engineered small intestine. The effect of implantation of large numbers of smooth muscle cells (SMC) for the regeneration of small intestine was also investigated.

METHODS

Two types of scaffolds with different cell densities were fabricated: low density (LD) of SMC in the scaffold and high density (HD) of SMC in the scaffold. Both scaffolds were implanted into defects of isolated ileum in a canine model. Animals were sacrificed at 8, 12, 18, and 24 weeks.

RESULTS

The area of engineered small intestine in the HD group was four times larger than that in the LD group, although that was smaller in size than the original size of the defect. There were no significant changes in the thickness of regenerated smooth muscle layer (SML) in the LD and HD groups. The numbers of endocrine cells gradually increased after implantation. At 18 weeks of regeneration, the number of ECC reached levels comparable to that of normal mucosa. The nerve fibers extended to the center of the graft area and were observed in regenerated SML and regenerated villi at 24 weeks.

CONCLUSIONS

The ECC and nerve fibers were regenerated in autologous in situ tissue-engineered small intestine. Seeding a large number of SMC was not sufficient for the regeneration of the small intestine in a tubular configuration.

Non-cavernomatous superior mesenteric thrombosis successfully recanalized with interventional radiological procedures carried out with a combination transmesenteric and transjugular approaches

This is the study of a 52-year-old man with oesophageal, rectal and anal varices caused by portal hypertension with complete obstruction of the superior mesenteric vein. Treatment by two sessions of interventional radiological procedures was successful. The first was a catheter-directed thrombolysis using the transmesenteric approach. The second was percutaneous transluminal angioplasty and stent implantation for the obstructed segment of the superior mesenteric vein and the creation of a transjugular intrahepatic portosystemic shunt. In the second session, devices were advanced over a guidewire inserted from the right jugular vein and pulled out of the ileocolic vein using the pull-through technique.

Comparison of effects in randomized controlled trials with observational studies in digestive surgery

OBJECTIVES

To compare the results of randomized controlled trials versus observational studies in meta-analyses of digestive surgical topics.

SUMMARY BACKGROUND DATA

While randomized controlled trials have been recognized as providing the highest standard of evidence, claims have been made that observational studies may overestimate treatment benefits. This debate has recently been renewed, particularly with regard to pharmacotherapies.

METHODS

The PubMed (1966 to April 2004), EMBASE (1986 to April 2004) and Cochrane databases (Issue 2, 2004) were searched to identify meta-analyses of randomized controlled trials in digestive surgery. Fifty-two outcomes of 18 topics were identified from 276 original articles (96 randomized trials, 180 observational studies) and included in meta-analyses. All available binary data and study characteristics were extracted and combined separately for randomized and observational studies. In each selected digestive surgical topic, summary odds ratios or relative risks from randomized controlled trials were compared with observational studies using an equivalent calculation method.

RESULTS

Significant between-study heterogeneity was seen more often among observational studies (5 of 12 topics) than among randomized trials (1 of 9 topics). In 4 of the 16 primary outcomes compared (10 of 52 total outcomes), summary estimates of treatment effects showed significant discrepancies between the two designs.

CONCLUSIONS

One fourth of observational studies gave different results than randomized trials, and between-study heterogeneity was more common in observational studies in the field of digestive surgery.

[A case of minimal invasive carcinoma from intraductal papillary mucinous neoplasm with invasive ductal carcinoma of the pancreas]

A 69-year-old man was referred to our hospital for epigastralgia. He was found to have elevation of serum amylase and CA19-9. Ultrasonography, abdominal CT, MRCP, ERCP and EUS showed the cystic lesion and a possibility of an other tumor. There was a stenosis of the main pancreatic duct (MPD) at the pancreas head and dilatation of the MPD from the body to the tail. Intraductal papillary mucinous neoplasm (IPMN) of the branch pancreatic duct was diagnosed, and there was a likelihood of ductal carcinoma of the pancreas. We therefore performed pancreatoduodenectomy. Pathological finding showed invasive carcinoma from an intraductal papillary mucinous neoplasm with invasive ductal carcinoma of the pancreas.

A novel immunotherapeutic modality with direct hemoperfusion targeting transforming growth factor-beta prolongs the survival of tumor-bearing rats

Immune responses are frequently depressed in patients with cancer. One of the reasons for a poor immune response is the presence of increased levels of immunosuppressive substances associated with tumor growth. Transforming growth factor-beta (TGF-beta), a representative immunosuppressive cytokine, plays various roles in the progression of cancer. To remove immunosuppressive substances from tumor-bearing hosts, we developed an immunosuppressive substance adsorption (ISA) column for direct hemoperfusion (DHP) treatment. It is filled with extra-fine fibers that can adsorb TGF-beta. In this study, we investigated the effects of this DHP treatment on serum levels and activities of TGF-beta, cellular immune responses, and anti-tumor effects in KDH-8 (TGF-beta-producing hepatocellular carcinoma cell line)-bearing rats. We further studied the ability of ISA fibers to adsorb tumor-associated immunosuppressive cytokines [TGF-beta, interleukin (IL)-6 and vascular endothelial growth factor (VEGF)] in samples of body fluids obtained from patients with metastatic cancer. DHP treatment decreased serum levels and activities of TGF-beta in tumor-bearing rats and restored T lymphocyte response to mitogen. Tumor growth in rats treated by DHP was significantly slower than that in untreated rats. The survival time of treated rats was significantly longer than that of untreated rats. The concentrations of TGF-beta, IL-6, and VEGF in the samples of human body fluids were decreased markedly by in vitro treatment with ISA fibers. These results suggest that DHP treatment with an ISA column, which removes TGF-beta and other immunosuppressive substances from the sera of tumor-bearing hosts, is potentially a new immunotherapeutic strategy for cancer.

[Plasma methylation-specific polymerase chain reaction as a diagnostic tool for esophageal cancer patients]

This study was designed to perform methylation-specific polymerase chain reaction (MS-PCR) assay for p16, E-cadherin, and retinoic acid receptor beta genes on peripheral blood samples from patients with esophageal squamous cell cancers, and compare the results of MS PCR with conventional serum tumor markers and the CEA-specific reverse transcriptase polymerase chain reaction (RT-PCR) assay. Preoperative blood samples were obtained from 30 patients with esophageal cancer, and were subjected to MS PCR and RT-PCR assays. Eleven patients (37%) showed aberrant methylation of the promoter region of at least one gene. On the other hand, circulating tumor cells were detected in 11 patients (37%). There was no correlation between both results and conventional tumor markers. The MS-PCR and RT-PCR assays can serve as complementary diagnostic markers for screening and monitoring patients with esophageal cancers.