Poorer prognosis in young patients with gastric cancer?

BACKGROUND/AIMS

Although the relationship between prognosis and age of patients with gastric cancer is controversial, a poorer prognosis in young patients has been suggested by most investigators. To further examine the hypothesis, a retrospective study was undertaken to analyze a large series of patients with gastric cancer in Taiwan.

METHODOLOGY

A total of 1,642 consecutive patients diagnosed with gastric cancer and receiving further management at one medical center from 1988 to 1993 were reviewed. The gender, TNM tumor stage, rate of curative resection and survival of the patients were compared in the young age group (< or = 39 years) and the old age group (> 39 years). Survival was estimated with the product-limit method and difference in survival was tested by the log-rank test. Multivariate analysis was done by the Cox proportional hazard model.

RESULTS

Among the 1,642 patients, 61 patients were in the young age group and 1,581 patients were in the old age group. There was no significant difference for the 2 groups of patients in the distribution of TNM stage (stage I: 20%; II: 8%; III: 13%; IV: 59% vs. 19%, 11%, 25% and 45% respectively, in the old age group, p = 0.098) and rate of curative resection (38% vs 51% in the old age group, p = 0.059). The overall 5-year survival showed no significant difference between the 2 groups (25% vs. 29% in the old). Subgroup analyses showed that survival after curative resection and survival without curative treatment (including palliative resection and no resection) also had no difference in the 2 groups. Multivariate analysis also showed that age was not an independent factor.

CONCLUSIONS

Although most reports suggested a dismal prognosis in young patients with gastric cancer, based on our findings, young patients (< or = 39 years) do not have a worse prognosis than older patients.

[Construction of expressing vector for phage display scFv and a mouse unspecified antibody library]

The display of antibody gene library on the surface of E. coli filamentous phage offers a new method of obtaining antibodies against specific antigens. In the paper, it is reported that a phagemid for phage display antibody, named after pFUW80, characterized expressing scFv either secretly or stickily. With a series of designed PCR primers, heavy-chain and light-chain variable region genes of mice antibodies were amplified and a mouse unspecified single-chain antibody library with the size of 1.2 x 10(6) clones was constructed. From this library, phage was selected out against antigen human IgG and detected by ELISA and partial sequence analysis. These primary results established the foundation for future research using this system.

Serum anti-p53 antibodies in gastric adenocarcinoma patients are associated with poor prognosis, lymph node metastasis and poorly differentiated nuclear grade

Mutation of the p53 tumour suppressor gene often leads to the accumulation of mutant p53 protein in tumour cells. Many cancer patients develop antibodies that recognize the overexpressed p53 protein. The presence of these antibodies is, in some tumour types, associated with poor prognosis. Gastric cancer is a highly prevalent disease associated with a high rate of mortality, there is a need for improved clinical and biological markers for disease behaviour. To investigate the clinical relevance of serum anti-p53 antibodies in patients with gastric adenocarcinoma, we have examined the sera of 501 gastric cancer patients for the presence of serum antibodies against the p53 protein. By immunoblotting analysis using a cell lysate containing overexpressed p53 protein as well as affinity-purified recombinant p53 protein as antigens, we have detected anti-p53 antibodies in 11.2% (61 of 501) of gastric cancer patients, but in none of 46 cancer-free individuals. The presence of anti-p53 antibodies was tightly associated with tumours of higher nuclear grade and lymph node metastasis, and a negative association was found between the presence of anti-p53 antibodies and survival. These results suggest that a preoperative test of serum anti-p53 antibodies in gastric cancer patients can be useful to identify subset of patients who may need gastrectomy with lymph node dissection and post-operative adjuvant therapy.

Relationship between hormone receptor concentration and tumor shrinkage in uterine myoma after treatment with a GnRHa

BACKGROUND

Uterine myomas are benign tumors of the uterus, occurring in up to 25% of women of reproductive age. We examined the possible causes for different degrees of volume reduction in patients with uterine myomas who received gonadotropin-releasing hormone agonist (GnRHa) treatment by investigating the hormone receptors at the end of GnRHa treatment.

METHODS

This trial was designed as a prospective study of five premenopausal women presenting with symptomatic uterine myoma. All patients were treated with a subcutaneous injection of goserelin depot 3.6 mg every four weeks for 16 weeks. Clinical examinations, hormonal evaluation and ultrasound determinations were performed before, during and after treatment. At the end of the treatment period, all patients underwent myomectomy. The concentrations of the unbound progesterone receptors and estrogen receptors were evaluated.

RESULTS

The volume of the uterine myoma decreased by 21% to 65%. The percentage of decrease in volume of treated uterine myomas was found to negatively correlate with the concentration of unbound progesterone receptors (r2 = 0.92, p = 0.008). This percentage was not significantly correlated with the concentration of unbound estrogen receptors (r2 = 0.02, p = 0.84).

CONCLUSIONS

The limited data available suggested that the volume decrease of uterine myomas in GnRHa-treated patients is partly dependent on the concentrations of unbound sex-hormone receptors in the uterine myomas.

Prognostic value of MIB-1 index and DNA ploidy in resectable ampulla of Vater carcinoma

OBJECTIVE

To evaluate the prognostic value of the proliferative factors, MIB-1 index, DNA ploidy, and S-phase fraction, and further to determine the independent prognostic factors in ampulla of Vater carcinoma after pancreaticoduodenectomy.

SUMMARY BACKGROUND DATA

Cell kinetics are important indicators of the biologic behavior of various human tumors, but only a few authors have reported the application of cell proliferative factors in ampulla of Vater carcinoma.

METHODS

Patients undergoing pancreaticoduodenectomy for ampulla of Vater carcinoma were included. Proliferative factors, MIB-1 index, and DNA contents, measured by flow cytometry, were evaluated and compared with the conventional clinicopathologic factors.

RESULTS

Ninety resectable ampulla of Vater carcinomas were included. By univariate analysis, MIB-1 index, DNA ploidy, S-phase fraction, stage, and lymph node status were significant prognostic factors. The 5-year survival rate was 40.7% for tumors with MIB-1 index < or =15% and 0% for those with MIB-1 index >15%. Diploid tumors had a significantly better prognosis than aneuploid. Outcomes of stage I and II tumors were more favorable than those of stage III and IV. After multivariate analysis, MIB-1 index, DNA ploidy, and stage remained as the independent prognostic factors. Among the three independent prognostic factors, MIB-1 index was the most powerful.

CONCLUSIONS

Both MIB-1 index and DNA ploidy provide important prognostic value and potentially complement the conventional prognostic factors in resectable ampulla of Vater carcinoma. MIB-1 index is the most powerful independent prognostic factor.

Diagnostic and prognostic values of CA 19-9 and CEA in periampullary cancers

BACKGROUND

The roles of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9) in periampullary cancers have not been clearly established. Diagnostic and prognostic values of these two tumor markers were clarified in this study.

STUDY DESIGN

Preoperative serum levels of CEA and CA 19-9, and clinicopathologic features were retrospectively reviewed in 143 surgical patients with periampullary cancer from 1989 to 1997.

RESULTS

There were 86 resectable and 57 unresectable periampullary cancers. CA 19-9 demonstrated significantly higher sensitivity in detecting these cancers than CEA. The cancer with unresectable lesion, total bilirubin >7.3 mg/dL, or tumor size >2 cm tended to associate with higher CA 19-9 level. CEA level was significantly higher in the tumor >2 cm, not in the tumor < or =2 cm. CA 19-9 was a significant prognostic factor in both resectable and unresectable periampullary cancers, but CEA was significant only in the resectable group. Multivariate analysis revealed that independent prognostic factors included CA 19-9, resectability, primary tumor, and stage, and CA 19-9 was the most important one.

CONCLUSION

CA 19-9 provided more important diagnostic and prognostic values than CEA in periampullary cancers and was the most important independent prognostic factor for periampullary cancers. This study recommends serum CA 19-9 as an adjunct in detecting periampullary cancers, in evaluating resectability, and in predicting prognosis.

Evaluation of a simplified staging system for prognosis of hepatocellular carcinoma

The current TNM (tumor, nodes, metastases) staging system for human hepatocellular carcinoma (HCC) has been challenged since a new T staging system was proposed to correlate the staging group with patient outcome after curative liver resection. The new T staging system proposed T1 as no vascular invasion, small size (< or = 5 cm), and solitary tumor. T2 was defined as the presence of one of the following factors: size greater than 5 cm, vascular invasion, or multiple tumors; T3 as the presence of two of the above three factors; and T4, the presence of all three factors. A total of 323 patients undergoing curative partial hepatectomy for HCC were studied. Kaplan-Meier survival analysis was used to evaluate the postoperative outcome. The new T staging showed good correlation between the staging group and patient outcome. The 1-year disease-free survival (DFS) rate and overall survival (OS) rate were 80.0% and 87.8% for stage 1 (n = 115), 67.6% and 81.6% for stage 2 (n = 136), 40.0% and 58.0% for stage 3 (n = 58), and 21.4% and 42.8% for stage 4 (n = 14), respectively. The 3-year DFS rate and OS rate were 61.0% and 64.5% for stage 1, 37.8% and 50.7% for stage 2, 21.4% and 29.8% for stage 3, and 21.4% and 34.3% for stage 4, respectively. When analyzed using the current International Union Against Cancer (UICC) pathologic (p) TNM staging system, the 1-year and 3-year DFS rates were 86.2% and 64.0% for stage 1 (n = 30), 73.9% and 50.0% for stage 2 (n = 182), and 46.8% and 22.3% for stage 3 (n = 111), respectively. Our results showed that, while both staging systems allow clear stratification of patients into prognostic groups, the modified TNM system is not superior to the UICCpTNM system in predicting survival of HCC patients after curative partial hepatectomy. A larger scale, multicenter study may be needed to test the revised TNM system.

Inhibition of hTAFII32-binding implicated in the transcriptional repression by central regions of mutant p53 proteins

We previously identified a movable and regulable inactivation function within the central region (CRts247) of a temperature-sensitive p53 (p53(ts)) mutant, p53(N247I). Here we showed that central regions from several p53(ts) mutants behaved similarly, i.e. they repressed a neighboring activation domain only when existing in the mutant status. Using chimeric protein GAL4VP16-CRts247 as an example, we demonstrated that de novo protein synthesis was not required for the reactivation of the chimeric protein, indicating that a post-translational mechanism was involved in the control of CRts247 activity. The CRts247-conferred thermo-regulability did not work via a mechanism demanding either an alteration of the subcellular compartmentalization of or the inactivation of DNA-binding activity of the GAL4 chimera. Further, CRts247 did not function in trans, eliminating the possibility that the observed repression was because of the competition for a putative factor(s) by the mutant p53 domain. Rather, CRts247 bestowed temperature-dependent interaction with hTAFII32 to the VP16 activation domain. In a parallel experiment, CRts247 also caused a large reduction in the affinity of hTAFII32 to the p53 activation domain at the nonpermissive temperature. These results strongly suggested that inhibition of hTAFII32 binding could be one of the mechanisms responsible for the transcriptional repression by mutant p53 central regions.

Heterotopic pancreas: a difficult diagnosis

Heterotopic pancreas is a rare disease. We evaluated 17 patients treated surgically at our hospital. Epigastric pain (77%), abdominal fullness (30%), and tarry stools (24%) were the three most frequent symptoms and signs. The lesions were diagnosed as gastroduodenal tumors by gastroduodenoscopy (67%) or upper gastrointestinal series (71%). Among these, only one gastric submucosal tumor was considered to be heterotopic pancreas preoperatively. Three patients were found to have gastric tumor by abdominal ultrasound. Computed tomography, small-intestinal series, barium enema, endoscopic retrograde cholangiopancreatography, angiography, and cholescintigraphy did not help in disclosing lesion. In about half of the patients, the lesions were located at the stomach. Tumor size varied from 1 to 3 cm. Surgical excision relieved symptoms. These findings indicated heterotopic pancreas is still a difficult disease for diagnosis, regardless of the improvements of diagnostic tools and techniques.

Surgical resection of hepatocellular carcinoma in elderly cirrhotic patients

BACKGROUND/AIMS

Both cirrhosis and old age have been reported to be risk factors for hepatic resection. This study evaluated the clinical results of hepatic resection in elderly hepatocellular carcinoma (HCC) patients with cirrhosis.

METHODOLOGY

During a 5-year period, 248 patients with HCC underwent curative hepatic resection. Among them, 24 elderly patients (age: > or = 70 years) with cirrhosis (Group I), 24 patients (age: > or = 70 years) without cirrhosis (Group II), and 98 patients (age: < 70 years) with cirrhosis (Group III) were selected for the study. The clinical and pathologic parameters, including pre-operative demographic features, surgical factors, pathological factors, DNA flow-cytometric analysis of the resected specimen, and post-resection prognosis were compared among the three groups.

RESULTS

Group I patients had a significantly higher incidence of small-size tumors, hepatitis C infection, concomitant esophageal varices, and minor resection with a shorter surgical margin in the resected specimen. The surgical morbidity and mortality of Group I was similar to that of Group II and III patients. However, the disease-free survival rate was significantly lower in the Group I patients than in Group II (p = 0.02) and Group III patients (p = 0.04).

CONCLUSIONS

Our findings indicate that although hepatic resection can be done safely in elderly cirrhotic HCC patients, the prognosis for these patients was less favorable even when curative resection was performed.

Effect of magnolol on in vitro mitochondrial lipid peroxidation and isolated cold-preserved warm-reperfused rat livers

BACKGROUND/AIM

A mechanism suggested to cause injury to preserved organs is the generation of oxygen free radicals. Lipid peroxidation is one of the biological damages caused by oxygen free radicals. It is our aim to investigate whether magnolol, a strong antioxidant, suppresses the generation of oxygen free radicals and improves the viability of cold-preserved warm-reperfused rat livers.

MATERIALS AND METHODS

In vitro lipid peroxidation was induced in rat hepatic mitochondria with ADP and FeSO4. The inhibitory effect of magnolol on lipid peroxidation was measured with oxygen consumption and malondialdehyde (MDA) formation. Subsequently, we preserved and reperfused rat livers in preservation solutions that contained magnolol. The hepatic enzymes and liver MDA were measured to assess the protective effect of magnolol on isolated rat livers.

RESULTS

In rat hepatic mitochondria, magnolol was 470 times more potent than alpha-tocopherol in inhibiting oxygen consumption and 340 times more potent than alpha-tocopherol in inhibiting MDA formation. Addition of magnolol to Ringer's lactate solution had a protective effect, in terms of MDA formation and leakage of hepatic enzymes, on warm-reperfused but not cold-stored liver tissue. Addition of magnolol to University of Wisconsin (UW) solution, a widely used preservation solution, did not modify the effect of this solution on isolated liver tissues.

CONCLUSIONS

We conclude that magnolol is an effective antioxidant and suppresses lipid peroxidation in rat liver mitochondria and can be used as a rinsing solution in protecting transplanted organs from lipid peroxidation during reperfusion, especially for those organs not preserved with UW solution.

Comparison of pylorus-preserving and classic pancreaticoduodenectomy

BACKGROUND

The authors present their recent experience with the treatment of periampullary lesions to compare the surgical technique, safety and prognosis between pylorus-preserving pancreaticoduodenectomy (PPPD) and classic pancreaticoduodenectomy (CPD).

METHODS

Prospective data from 100 patients with periampullary lesions treated with either PPPD or CPD between January, 1991, and June, 1997, were evaluated, including demographic data, surgical technique, surgical risk and prognosis.

RESULTS

There were 35 patients treated with PPPD and 65 treated with CPD. The operating time was significantly shorter in the PPPD group (9.3 +/- 0.3 hours) than in CPD (10.4 +/- 0.3 hours). The average overall blood loss was 1,275 +/- 71 ml, with no statistical difference between PPPD and CPD groups. The overall complication rate was 56%, with 54% in the PPPD group and 57% in the CPD group (p = 0.755). The overall mortality was 4%, with 0% in the PPPD group and 6.2% in CPD (p = 0.655). There was no statistical difference in survival time for overall periampullary cancers between the PPPD and CPD groups (median = 28.0 vs 26.5 months, p = 0.393). The difference in survival time was still of no significance between the PPPD and CPD groups when the periampullary cancers were further stratified into pancreatic head cancer and nonpancreatic periampullary cancer.

CONCLUSIONS

Morbidity and mortality of PPPD did not exceed that of CPD, and the prognosis after PPPD was not compromised in patients with periampullary cancer. PPPD, with a shorter operating time, can be a safe and effective alternative to CPD in the treatment of periampullary lesions.

Serum albumin concentration as a prognostic indicator for acute surgical patients

BACKGROUND

Whether or not the rapid reduction in serum albumin concentration in acute surgical patients without evidence of pre-existing energy deficit correlates with outcome has yet to be studied. In this study, we attempted to determine whether albumin infusion or nutritional supplementation can improve outcome for patients with hypoalbuminemia.

METHODS

We retrospectively reviewed 80 non-calorie-deficient patients newly admitted to the surgical intensive care unit of the Veterans General Hospital-Taipei with complete data for serum albumin concentration and APACHE II score within 24 hours from August, 1998, to February, 1994. The relationships between age, sex, diagnosis, reason for intensive care, albumin infusion, hyperalimentation, APACHE II score, serum albumin concentration, days in intensive care and prognosis within three months were analyzed.

RESULTS

Univariate statistical analysis showed that the serum albumin concentration and APACHE II score correlated well with patient survival (p = 0.002 and p = 0.025, respectively). Multivariate analysis showed that hypoalbuminemia was independently associated with patient outcome (p = 0.003). Simple albumin infusion or hyperalimentation for patients with hypoalbuminemia did not improve survival.

CONCLUSIONS

The results suggest that serum albumin concentration appears to be a good prognostic marker for acute surgical patients. While decreased serum albumin concentration may also reflect poor nutritional status, for patients with moderate to severe hypoalbuminemia due to other causes, simple albumin infusion and/or nutritional support did not significantly improve survival. Consequently, aggressive treatment of the underlying disease is far more important.

Factors correlated with number of metastatic lymph nodes in gastric cancer

OBJECTIVE

We had previously reported a reasonable categorization of the number of positive lymph nodes (LN: 0, 1-4, 5-8, and > 8) as a prognostic indicator. This study was an extension, to see which factors correlated with number of positive lymph nodes.

METHODS

A total of 533 patients with gastric adenocarcinoma, who underwent curative surgery between January 1988 and December 1995, were entered into this study. Patients were divided into four groups according to metastatic LN number (0, 1-4, 5-8, and > 8). Their survival and clinicopathological factors were analyzed.

RESULTS

A total of 16,457 LNs, with an average of 30.9 per specimen, were removed, of which 1686 (10.2%) showed metastases. The 5-yr cumulative survival rate decreased as the number of metastatic LNs increased, ie., 91.3% for LN 0; 67.4% for LN 1-4; 37.2 for LN 5-8, and 14.1% for LN > 8. Multivariate analyses showed that depth of cancer invasion (odds ratio: 2.4), gross appearance (odds ratio: 1.9), size (odds ratio: 1.9), and location (odds ratio: 1.4) of tumor were four independent factors correlated with the number of metastatic LNs. Number of metastatic LNs increased with advanced Japanese nodal stage and UICC-TNM stage.

CONCLUSIONS

Depth of tumor invasion, and gross appearance, size, and location of tumor were four pathological factors independently correlated with number of metastatic LNs in gastric cancer.

Allelic loss of the BRCA1 and BRCA2 genes and other regions on 17q and 13q in breast cancer among women from Taiwan (area of low incidence but early onset)

We have examined the role of the breast cancer susceptibility genes BRCA1 and BRCA2 and other loci in the vicinity of these 2 genes on the long arms of chromosomes 17 and 13 (17q and 13q) for the presence of genomic deletions in breast cancer among Taiwanese women. Breast cancer in Taiwan is particularly characterized by its low incidence rate and its early age of tumor onset. Twelve microsatellite markers spanning the region 17q12-21 and 8 microsatellite markers spanning the region 13q12-14 were analyzed for allelic loss or loss of heterozygosity (LOH) in 90 patients with primary infiltrating ductal carcinoma. Compared with the background LOH level (10-12%) estimated by LOH at 4 unrelated loci, 17 markers (11 at 17q and 6 at 13q) demonstrated a significantly increased frequency (21-42%) of allelic loss (p < 0.05). Subsequent construction of deletion maps based on LOH at these significant loci localized the 6 smallest regions of overlap, including those harboring BRCA1, BRCA2, the retinoblastoma gene and 3 novel regions (the 1st located approximately 0.5 to 1 cM telomeric to BRCA1, the 2nd centromeric to BRCA1 flanked by D17S857/D17S846 and the 3rd closely adjacent to BRCA2), suggesting sites of susceptibility genes. Allelic loss at BRCA1 and BRCA2 was specifically associated with poorly differentiated tumors.

Surgical treatment and outcome in patients with a hepatocellular carcinoma greater than 10 cm in diameter

BACKGROUND

Hepatocellular carcinoma (HCC) over 10 cm in diameter at the time of diagnosis continues to account for a number of patients undergoing hepatic resection. This study evaluated the clinicopathological features and outcome following surgery for large HCC.

METHODS

Forty patients with a large HCC (greater than 10 cm) (group 1) resected between 1991 and 1996 were studied retrospectively. They were compared with 245 patients who had smaller HCCs (10 cm or less) (group 2).

RESULTS

No patient in group 1 had hepatitis C infection compared with 22.9 per cent in group 2 (P=0.001). Patients in group 1 were significantly younger, had higher alpha-fetoprotein levels (16750 versus 1864 ng/ml; P < 0.001), better liver function, a higher incidence of multiple tumours (27 of 40 versus 42.0 per cent; P=0.003) and venous invasion (35 of 40 versus 52.2 per cent; P < 0.001), and underwent more major resections (37 of 40 versus 26.5 per cent; P < 0.001) than those in group 2. Morbidity and mortality rates and hospital stay were comparable in the two groups. For group 1, the 1-, 3- and 5-year disease-free survival rates were 42, 30 and 28 per cent respectively. Multiple tumours, venous invasion and impaired liver function were factors associated with recurrence.

CONCLUSION

Large HCC had specific clinicopathological features. In selected patients, resection is safe and offers the chance of long-term disease-free survival.

Cordyceps sinensis increases the expression of major histocompatibility complex class II antigens on human hepatoma cell line HA22T/VGH cells

Previous studies suggest that down-regulation of the major histocompatibility complex (MHC) antigens on the cell surface of certain tumors results in an escape of immune surveillance. Cordyceps sinensis is well known for its modulatory effect on host immune system. To investigate the modulatory effect of Cordyceps sinensis on MHC class II antigen expression on hepatoma cells, immunostaining with monoclonal antibody (MAb) L243, against the HLA DR region of MHC class II antigens on human hepatoma cell line HA22T/VGH was analyzed by using flow cytofluorimetry. The degree of fluorescence intensity on L243(+) cells was expressed as relative mean fluorescence intensity (RMFI). The extract of Cordyceps sinensis (VGH-CS-ME-82, 40 micrograms/ml) was found to increase the MHC class II antigen expression on HA22T/VGH cells with the percentage of L243(+) cells 40.2 +/- 2.5 and RMFI 6.6 +/- 0.4; whereas cells without treatment disclosed the percentage of L243(+) cells 17.2 +/- 1.4 and RMFI 5.4 +/- 0.3, respectively (p < 0.05). There was a dose-related increase in the degree of fluorescence intensity in terms of RMFI on VGH-CS-ME-82 induced cells. The RMFI in cells treated with IFN-gamma 0, 0.2 and 5 ng/ml were 5.4 +/- 0.3, 8.2 +/- 0.4, and 24.9 +/- 1.5, respectively; whereas the RMFI in cells co-incubated with VGH-CS-ME-82 (40 micrograms/ml) and IFN-gamma 0, 0.2 ng/ml and 5 ng/ml were 6.7 +/- 0.2 (p < 0.05), 9.2 +/- 0.9 (p < 0.1) and 29.5 +/- 1.2 (p < 0.005), respectively. We conclude that VGH-CS-ME-82, either alone or with IFN-gamma induction, increases the MHC class II antigen expression on hepatoma cell line HA22T/VGH, which will shed light into the present immunotherapy, and make the host immune surveillance more effective against tumor cells with down-regulated MHC class II antigen expression.

Molecular cloning of bovine telomerase RNA

Telomerase is a ribonucleoprotein reverse transcriptase essential for the maintenance of telomere length. However, the available information concerning the biochemical and structural aspects of mammalian telomerases is scarce, primarily due to the low abundance of these enzymes and the difficulty and expense involved in its purification. To overcome these problems, we started to purify and characterize telomerase from bovine testis. Bovine telomerase was purified over columns of hydroxyapatite, DEAE-Sepharose, heparin-agarose, phenyl-agarose and spermine-agarose. In a sedimentation study performed using a 15-40% glycerol gradient, partially purified bovine telomerase exhibited an apparent molecular weight of more than 1000 kDa. One 435-bp RNA, bTR, was cloned from the most purified telomerase fraction and shown to be co-purified with telomerase activity in a glycerol gradient. bTR shares 83% similarity to the human telomerase RNA and 65% to the mouse telomerase RNA. A putative template region encompassing 10 nucleotides (5'-CUAACCCUAA-3') complementary to the mammalian telomere sequence (TTAGGG)n is located between nucleotides 38-47 of bTR. Besides, the bTR 5'-flanking region shares only three regulatory elements with that of hTR: a TATA-like sequence, a CCAAT box and an E1A-F box. Furthermore, the addition of in-vitro transcribed bTR reconstituted telomerase activity after removal of the endogenous bTR by micrococcal nuclease digestion. Northern blot analysis identified a single RNA of about 430-440 nucleotides expressed in the bovine testis and an immortalized bovine cell line. Taken together, these data strongly suggest that bTR is the RNA component of bovine telomerase.

Submicromolar paclitaxel induces apoptosis in human gastric cancer cells at early G1 phase

Paclitaxel induced apoptosis has been reported in many cancer cell lines, but the relationship between G2/M phase arrest and apoptosis is not clear. We have reported that low dose (10 nM) paclitaxel induced apoptosis in gastric cancer cells without G2/M phase arrest. In this study, SC-M1 gastric cancer cells were synchronized at early G1, late G1, S and G2/M phases by staurosporine, mimosine, hydroxyurea and berberine, respectively. We have found that paclitaxel could not induce apoptosis of gastric cancer cells in late G1, S and G2/M phases; however, paclitaxel induced apoptosis in the early G1 phase. Our results suggest that cells arrested at G2/M phase by paclitaxel eventually entered the early G1 phase then proceeded to apoptosis.

Serum hepatocyte growth factor level associate with gastric cancer progression

We have measured serum HGF levels from 80 gastric cancer patients and 51 normal subjects by enzyme-linked immunosorbent assay. The results showed that the mean value of serum HGF level in gastric cancer patients was significantly higher than in normal subjects (0.30 +/- 0.02 vs 0.22 +/- 0.05 ng/ml; p = 0.005). The increase was stage related. Patients with serum HGF < or = 0.30 ng/ml survived longer than those with serum HGF > 0.30 ng/ml (p = 0.02). These data suggest that HGF involve in progression of gastric cancer.

Profiling expression patterns and isolating differentially expressed genes by cDNA microarray system with colorimetry detection

A high-density cDNA microarray with colorimetry detection system to simultaneously monitor the expression of many genes on nylon membrane is described and characterized. To quantify the expression of genes and to isolate differentially expressed genes, the southern hybridization process on filter membranes was employed. The levels of gene expression were represented by color intensities generated by colorimetric reactions in place of hazardous radioisotopes or costly laser-induced fluorescence detection. The gene expression patterns on nylon membranes were digitized by devices such as an economical flatbed scanner or a digital camera. The quantitative information of gene expression was retrieved by image analysis software. Quantitative comparison of the northern dot-blotting method with the microarray system is described. Applications employing single-color detection as well as dual-color detection to isolate differentially expressed genes among thousands of genes are demonstrated.

Serum progesterone levels in patients with gastric adenocarcinoma before and after gastrectomy

BACKGROUND

Having observed that progesterone receptors exist in all gastric carcinoma tissues, the authors determined that serum progesterone levels in gastric carcinoma patients were worthy of evaluation.

METHODS

Serum progesterone levels were determined in patients with gastric adenocarcinoma and in patients with benign disease who served as controls. All female patients were older than 55 years. The clinicopathologic significance of their serum progesterone levels was determined.

RESULTS

In male patients (n = 122), the serum progesterone level (mean +/- standard deviation) was significantly higher than in the male control group (n = 163) (0.264+/-0.261 vs. 0.142+/-0.113 ng/mL; P < 0.001) and showed a tendency to be stage-related (P = 0.029). Serum progesterone levels significantly decreased after gastrectomy in patients with disease at Stage I (n = 27), II (n = 20), and III (n = 32), but not IV (n = 7). In 11 patients who died of recurrence, the serum progesterone levels were decreased when they were disease free but raised when recurrence was clinically evident. Patients with serum progesterone levels > 0.264 ng/mL survived for significantly shorter periods than those with levels < or = 0.264 ng/mL (P = 0.039). However, serum progesterone level was not an independent predictor of survival. Among the female patients (n = 12), the serum progesterone level (mean +/- standard deviation) of patients with gastric carcinoma was 0.427+/-0.428 ng/mL, whereas that of the control group (n = 17) was 0.217+/-0.451 ng/mL; the difference was statistically significant (P = 0.02). In female disease free patients studied postoperatively, the progesterone after gastrectomy showed a tendency to decrease, but this difference was not statistically significant (0.444+/-0.368 vs. 0.175+/-0.150 ng/mL; P = 0.091; n = 7).

CONCLUSIONS

These data suggest that serum progesterone level reflects the presence or absence of gastric carcinoma by some unknown mechanism.

Diagnostic and prognostic values of plasma levels of fibrinolytic markers in gastric cancer

In the present study, we determined the plasma and tissue concentrations of tissue-type plasminogen activator, urokinase-type plasminogen activator, plasminogen activator inhibitor-1, plasminogen activator inhibitor-2 and urokinase-type plasminogen activator receptor in 32 patients with pathology-proved gastric cancer. The plasma levels of the same markers were compared in 37 patients with benign gastric ulcer in order to find out if these plasma levels could be used to evaluate the prognostic value in patients with gastric cancer. Plasma plasminogen activator inhibitor-1 was significantly higher in gastric cancer than in benign gastric disease (p < 0.0005), whereas plasma urokinase-type plasminogen activator was significantly lower in patients with gastric cancer than in those with benign ulcer (p = 0.003). There was no significant correlation between tissue and plasma concentrations of the same parameters. The plasma and tissue levels of fibrinolytic parameters were not affected by tumor size or distant metastasis, whereas tumor tissue concentration of urokinase-type plasminogen activator receptor and plasminogen activator inhibitor-2 were significantly higher in N0 than in N1 and N2, and tissue plasminogen activator inhibitor-1 was significantly higher in N0 than in N1. Plasma levels of the five fibrinolytic parameters could not take the place of the corresponding tissue concentrations on the diagnosis and prediction of prognosis in patients with gastric cancer. Tissue concentrations of urokinase-type plasminogen activator receptor and plasminogen activator inhibitor-2, especially the latter, can be used to predict lymph node involvement in patients with gastric cancer.

Percutaneous transhepatic duodenal drainage as an alternative approach in afferent loop obstruction with secondary obstructive jaundice in recurrent gastric cancer

Two cases are reported of chronic, partial afferent loop obstruction with resultant obstructive jaundice in recurrent gastric cancer. The diagnosis was made by characteristic clinical presentations, abdominal computed tomography, and cholescintigraphy. Percutaneous transhepatic duodenal drainage (PTDD) provided effective palliation for both afferent loop obstruction and biliary stasis. We conclude that cholescintigraphy is of value in making the diagnosis of partial afferent loop obstruction and in differentiating the cause of obstructive jaundice in such patients, and PTDD provides palliation for those patients in whom surgical intervention is not feasible.