Enhanced expression of the multidrug resistance gene in vindesine-resistant human esophageal cancer cells

We developed and characterized a new series of low- and high-grade multi-drug-resistant (MDR) cell lines of human esophageal carcinoma. Eight vindesine-resistant clones, SH-1-V1, SH-1-V2, SH-1-V3, SH-1-V4, SH-1-V5, SH-1-V6, SH-1-V7, and SH-1-V8 were isolated from the human esophageal cancer cell line, SH-1, by stepwise selection on exposure to increasing doses of vindesine. SH-1-V1 to SH-1-V8 acquired resistance to vindesine, in a stepwise manner, from 3- to 115-fold over findings in the parental SH-1 cells. The most resistant clone, SH-1-V8, was cross-resistant to other anticancer agents such as vincristine, actinomycin D, and daunomycin, thereby suggesting acquisition of the MDR phenotype. In SH-1-V8 cells, cellular accumulation of vincristine decreased and an MDR reversal agent, cepharanthine, potentiated the cytocidal action of vindesine. The expression of MDR1 mRNA was enhanced and amplification of the MDR1 gene was observed in clones SH-1-V4, SH-1-V5, SH-1-V6, SH-1-V7 and SH-1-V8; expression of MDR1 mRNA was detectable without gene amplification in the remaining 3 clones. The enhanced expression of the MDR1 gene may be involved in the acquisition of vindesine resistance in human esophageal cancer cells.

Extensive lymphadenectomy for thoracic esophageal carcinoma: a two-stage operation for high-risk patients

Extensive lymphadenectomy (ELA) for esophageal carcinoma has always been limited to low-risk patients; however, we have developed a two-stage operation which extends the indications for ELA to include certain high-risk patients. Of 70 patients who underwent transthoracic subtotal esophagectomy for thoracic esophageal carcinoma between 1986 and 1991, 48 qualified for ELA which was performed on 45, including 27 low-risk patients (group A) whom underwent the traditional one-stage operation, while 18 high-risk patients underwent the two-stage operation (group B). The number of hospital deaths and postoperative complications was similar between the two groups. The median survival was 26 months in group B and 17 months in group A. The 40-day delay in resection of the neck and abdominal nodes in the two-stage operation did not significantly affect lymph node metastases, postoperative recurrence, or long-term survival. Thus, the two-stage operation is an oncologically meaningful approach to the treatment of high-risk patients who present with thoracic esophageal carcinoma.

Laparoscopic surgical correction of circumcaval ureter

Laparoscopic transposition and reanastomosis of a circumcaval ureter were performed in a 52-year-old man with right flank pain. A preoperative perfusion pressure study revealed abnormally high intrapelvic pressure. Under laparoscopy, the renal pelvis was divided above the ureteropelvic junction and the ureter was relocated from behind the vena cava. A 5 cm segment of redundant ureter containing the postcaval segment was resected and the ureteral end and renal pelvis were reapproximated with interrupted sutures by intracorporeal knot typing. The postoperative convalescence was uneventful, not necessitating the administration of analgesics. The patient resumed full activities 3 weeks later. The intravenous urogram and renogram obtained 2 months after the operation revealed remarkable improvement in the ureteral obstruction.

[DNA stemline heterogeneity as preoperative prognostic factor in esophageal cancer]

Flow cytometric nuclear DNA analysis was performed on 36 preoperative endoscopic biopsy specimens and 89 surgically resected specimens of esophageal carcinomas without preoperative radiotherapy. Carcinomas with aneuploid or DNA stem-line heterogeneity had a higher frequency of lymph node metastasis (p < 0.01). The correspondence rate of nuclear DNA ploidy patterns was 97% between biopsy and resected specimens, and that of heterogeneity was 72%. Though only six cases showed heterogeneity in biopsy specimens out of 12 cases which showed heterogeneity in resected specimens, preoperative detection of heterogeneity was supposed to be more accurate by an increase of biopsy specimens. DNA analysis of biopsy specimens may be a possible indicator of the malignant potential of esophageal carcinoma.

A regulatory subunit of smooth muscle myosin bound phosphatase

The relationship between two putative myosin-binding subunits of smooth muscle myosin phosphatase was investigated. A monoclonal antibody (MoAb) to the 58 kD component of smooth muscle myosin-bound phosphatase (MBP) cross-reacted with a 130 kD protein in extracts of fresh chicken gizzards. The MoAb in combination with protein A immunoprecipitated from gizzard extracts a complex of the 130 kD protein plus the 38 kD catalytic subunit of the type 1 delta protein phosphatase. It is proposed that the 130 kD component is a native subunit of MBP and that the 58 kD protein is its proteolytic degradation product. The distribution of the 130 kD component in chicken tissues was screened using the MoAb. An immunoreactive band of appropriate mass was detected in all tissues except liver and skeletal muscle. Higher concentrations of the 130 kD component were evident in the smooth muscle samples.

Acetylsalicylate (ASA)-induced mitochondrial dysfunction and its potentiation by Ca2+

Although it has been suggested that acetylsalicylate (ASA)-induced mitochondrial dysfunction plays an important role in the pathogenesis of Reye's syndrome, administration of ASA alone does not cause this syndrome in therapeutic doses. We noted, however, that Ca2+ plays important roles in the regulation of cellular functions. ASA at concentrations of 250 microM or less, which had little effect on succinate-linked respiration, impaired Ca2+ accumulation in liver mitochondria by causing an increase in Ca2+ release. ASA plus Ca2+, which in concentrations of 150 microM or less alone had little effect on mitochondrial respiration, inhibited state 3 respiration and dinitrophenol-induced uncoupling of respiration. In addition, ASA plus Ca2+ increased state 4 respiration and ATPase activity. These results indicate that ASA plus Ca2+ impaired mitochondrial ATP synthesis, and suggest that ASA and ASA-induced Ca2+ increases in cytosol form a vicious circle of effects. Furthermore, oral administration of ASA (150 mg/kg for 5 days running) to rats did not affect mitochondrial structure or liver function, but resulted in aberrations of mitochondrial respiration. These results suggest that even therapeutic doses of ASA may induce alteration in mitochondrial function.

Differences in the effects of two hexachlorobiphenyls on superoxide generation by polymorphonuclear leucocytes stimulated by N-formyl-methionyl-leucyl-phenylalanine and phorbol myristate acetate

The effects of hexachlorobiphenyls (HCBs) on superoxide (O2-) generation by guinea pig polymorphonuclear leucocytes were examined. 2,3,6,2',3',6'-HCB by itself had only a weak inductive effect on O2- generation. This compound, however, enhanced O2- generation stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP) about twofold, but not the generation induced by phorbol myristate acetate (PMA). On the other hand, 3,4,5,3',4',5'-HCB suppressed O2- generation stimulated by both FMLP and PMA. The inhibitory potency of this compound was far greater with PMA (ID50, 5 microM) than with FMLP (ID50, 40 microM).

Extended survival time for esophageal cancer patients treated with aggressive surgery and concurrent chemoradiation

In attempts to improve overall long-term survival of patients with esophageal cancer, including medically inoperable patients and operable ones with disseminated disease, we treated operable patients with aggressive surgery and postoperative chemoradiation, and inoperable patients with chemoradiation alone. Chemoradiation consisted of 5,000-6,000 cGy of radiation and two courses of chemotherapy (cisplatin, vindesine, and pepleomycin). Of 90 patients seen between 1986 and 1991, 63 operable patients underwent surgery and 35 received postoperative chemoradiation, while 19 of 27 inoperable patients received chemoradiation. Results were compared with those of 48 unselected historical control patients treated since 1981. Survival at 5 years was significantly improved for the multimodality group (17.7 +/- 5.0%), as compared with the historical control group (10.4 +/- 4.4%). Thus, the overall therapy for patients with esophageal cancer has been improved.

c-myc mRNA overexpression is associated with lymph node metastasis in colorectal cancer

To elucidate the relationship between oncogene overexpression and malignant potential of colorectal cancer, the expression of three genes, c-myc, c-fos and c-Ki-ras was examined. Northern blot hybridisation was performed on fresh tissues excised from 35 patients with primary colorectal cancer. Overexpression of c-myc mRNA was evident in 25 of the patients (71%). Tumours with c-myc overexpression had a significantly higher frequency of lymph node metastasis than did those without (68 versus 20%, P < 0.05). The survival rate tended to be poorer (P = 0.06) in patients with c-myc overexpression (79% for 3 years) than in those without it (100%). We found no significant relationship between overexpression of the other two genes and pathological features. These findings suggest that c-myc overexpression is one parameter which can be used to determine the malignant potential of colorectal cancer.

DNA stem line heterogeneity in esophageal cancer accurately identified by flow cytometric analysis

BACKGROUND

This study was designed to evaluate the importance of DNA stem line heterogeneity in determining the malignant potential of esophageal cancer.

METHODS

Flow cytometric analysis of intratumor heterogeneity of DNA contents was performed on step-sectioned slices of 57 resected esophageal carcinomas.

RESULTS

DNA stem line heterogeneity, as assessed by DNA content measurements, was present in 25 (44%) tumors; 6 (11%) were a combination of diploid and aneuploid DNA pattern, and 19 (33%) had two or more aneuploid peaks with different DNA contents (multiploid). Of the remaining 32 homogeneous tumors, 4 showed only a diploid DNA pattern in all samples examined, whereas 28 tumors had only the aneuploid pattern. Tumors with the heterogeneous DNA pattern had a significantly higher frequency of lymph node metastasis than did those with the homogeneous DNA pattern (P < 0.05).

CONCLUSIONS

For evaluation of the highly malignant potential of esophageal carcinoma by nuclear DNA contents, it is important to identify accurately intratumoral heterogeneity. Because different DNA stem lines were evident in different areas of the lesion, evaluation of multiple specimens from a wide area of each lesion is needed to determine with accuracy the degree of intratumor DNA stem line heterogeneity.

Autopsy report of acute necrotizing opticomyelopathy associated with thyroid cancer

We report an autopsied case of paraneoplastic necrotizing myelopathy. The patient had bilateral blindness, quadriplegia, and dyspnea of acute onset and died without remission 7 weeks later. The severe tissue necrosis and demyelination were found in the optic chiasm and from the medulla oblongata throughout the whole length of spinal cord. A papillary carcinoma was found in the thyroid gland at autopsy. In the present case IgG, myelin basic protein and activated helper T cells were increased in the CSF at onset, suggesting a mechanism of autoimmune demyelination for the condition.

Detection of a central nervous system lesion in a patient with Fisher's syndrome

We report a 57-year-old man with Fisher's syndrome in whom both peripheral and central nervous system (CNS) lesions were detected. Clinical electrophysiological examinations including peripheral conduction studies, SEPs and BAEPs indicated conduction delay in the CNS as well as in the peripheral nerve.

An autopsy case of intracranial hemorrhage during tissue plasminogen activator infusion

We describe an autopsy case of severe intracranial hemorrhage which occurred during the infusion of tissue plasminogen activator (t-PA) for acute myocardial infarction. A 75-year-old man was admitted with substernal chest pain of 3-h duration and electrocardiographic changes consistent with an acute inferior myocardial infarction. Physical examination was unremarkable, except for an initial blood pressure reading of 160/96 mmHg. The patient received 3,000 IU intravenous heparin followed by a 2.4 x 10(6) IU bolus dose of tissue plasminogen activator (t-PA) (Alteplase). This was followed by a drip infusion of 21.6 x 10(6) IU of t-PA over 1 h (total dose 41 mg). Thirty minutes after the infusion of t-PA was initiated, the patient suddenly lost consciousness and began to have violent convulsions, followed by cardiac arrest. Autopsy revealed massive hemorrhage in the bilateral cerebrum and brain stem. To our knowledge, this is the first case of sudden death during t-PA infusion therapy.

Organ function index: a predictive marker of operative mortality based on multiple organ dysfunctions in patients with esophageal cancer

To evaluate the risk of transthoracic esophagectomy for cancer based on the overall impairment of vital organs, we examined pulmonary, cardiac, renal and hepatic functions using 18 markers in 35 patients between 1982 and 1984. A discriminant analysis proved useful in determining whether or not the patients would be at risk of operative mortality (operative death and hospital death), based on the overall impairment of vital organs. The accuracy of the prediction of operative mortality by this model, the organ function index (OFI), was 91.4%. The OFI was then applied to 66 patients seen between 1986 and 1991. During this period, a change in policy for performing transthoracic esophagectomy and perioperative care on patients with impairment of multiple organs was associated with a decrease in operative mortality. We conclude the OFI to be beneficial in evaluating the risk of operative mortality based on mild to moderate dysfunctions of multiple vital organs in patients with esophageal cancer.

Isolation and characterization of the StyD4I restriction endonuclease, a neoschizomer of ScrFI, from Escherichia coli K-12 carrying a small multicopy Hsd plasmid of Salmonella typhi origin

A restriction endonuclease, designated StyD4I, a neoschizomer of ScrFI, has been isolated from Escherichia coli K-12 carrying a small multicopy host specificity for DNA (Hsd) plasmid of Salmonella typhi D4 origin. In the presence of 10 mM Mg2+, StyD4I cleaves the sequence 5'-/CCNGG-3' and generates a 5-nucleotide cohesive end. StyD4I should be useful for recombinant DNA technology, because of the stability and ease in handling the producer cells.

Swelling-induced O2- generation in guinea-pig neutrophils

Without the addition of any exogenous stimuli, neutrophils generated O2- and then ceased in a reversible manner that correlated with cellular swelling and contraction. The nature of the possible mechanism responsible for this O2- generation was studied and compared with that observed in the triggering of stimulant-dependent O2- generation (respiratory burst). The swelling-induced O2- generation was inhibited by diphenyliodonium, and was independent of the functional distortion of mitochondrial and/or microsomal electron transport and xanthine oxidase. This suggested that such generation was involved in respiratory-burst oxidase activation; however, this generation was not accompanied by any new phosphorylation of the 47-kDa protein or of tyrosine proteins. Dihydrocytochalasin B potentiated the O2- generation. The cellular swelling produced a priming effect on the triggering of respiratory burst with different stimuli. Cellular contraction, conversely, suppressed the respiratory burst. The structural specificity of the swelling-induced plasma membrane modulation for the O2- generation was suggested by the finding that modulation of plasma membrane structures by various non-ionic detergents per se inhibited O2- generation. Lipophilic and positively-charged agents inhibited the generation and this inhibition was abrogated by negatively-charged, but not by non-ionic agents. Negatively-charged agents potentiated the O2- generation. These results suggest that both the interaction of the plasma membrane with the cytoskeleton and an increase in net negative charges at the plasma membrane play important role in evoking O2- generation; this is discussed and compared with the signal transduction reported previously for respiratory burst.

Risk factors associated with postoperative mortality in patients with esophageal cancer

We examined how impaired host defense mechanisms contribute to fatal complications following transthoracic esophagectomy for malignancy, and compared them with other risk factors. Risks associated with operative mortality were categorized into 5 groups. Twelve of 80 patients had postoperative fatal complications. Five variables in the category of impaired defense mechanisms predicted fatal complications with an accuracy of 86.3%. The accuracy of prediction by preoperative vital organ dysfunction, other preoperative risks, intraoperative risks, and perioperative risks was 87.3%, 90.0%, 87.5%, and 85.0%, respectively. When the 5 groups of risk variables were considered together, the accuracy increased to 93.8%. We conclude that impaired defense mechanisms are one of the important risk factors that contribute to postoperative fatal complications and should be considered with other risk factors when predicting mortality of transthoracic esophagetcomy.

[The intensity of hst-1 gene amplification and malignant potential of esophageal carcinoma in relation to intratumoral heterogeneity]

Amplification of hst-1 gene is associated with poor prognosis in patients with esophageal carcinoma. Since there is a high frequency of DNA stem-line heterogeneity, we studied intratumoral heterogeneity of hst-1 amplification, and evaluated whether or not the intensity of hst-1 amplification is associated with the malignant potential of esophageal carcinoma. A total of 73 patients with esophageal carcinoma who had undergone esophagectomy were studied. Intratumoral heterogeneity of hst-1 amplification was examined in two to four sections of tumour specimens which showed mainly DNA heterogeneity in 27 of these patients. The judgement of hst-1 amplification in the same tumor was identical in all of the 27 patients, although its intensity was not identical in some cases. And in 73 patients, postoperative recurrence in organs showed a high incidence (78%) in the hst-1 amplification group with a high intensity (over 7-fold). Therefore, hst-1 amplification exceeding 7-fold can serve as an indicator to predict the high grade of malignant potential of esophageal carcinoma.

[Preoperative evaluation of malignant potential in esophageal carcinoma by nuclear DNA contents]

Employing surgically resected specimens from patients without preoperative radiation therapy, we measured the nuclear DNA contents in order to evaluate the malignant potential of esophageal carcinoma. The association of the DNA index (DI) > or = 1.7 and the intratumoral DNA heterogeneity of biopsy specimens from patients with or without preoperative radiotherapy was also analyzed in relation to problems related to preoperative evaluation of nuclear DNA contents using biopsy specimens and the influence of irradiation on nuclear DNA contents. Esophageal carcinomas in 128 cases were studied. Nuclear DNA content was measured for biopsy specimens as well as surgically resected tumors by flow cytometry according to the method of Hedley and colleagues. HET was found in 42% of surgically resected specimens, but in only 18% of biopsy specimens. In 90% of cases, dominant DI of the resected tumor was also found in the biopsy specimens. Cases of DI > or = 1.7 showed a poorer prognosis than those with DI < 1.7 in cases with preoperative radiotherapy (p < 0.05) as well as in those without it. These results indicated that DI can be an indicator for highly malignant potential of esophageal carcinoma when measuring nuclear DNA contents using not only biopsy specimens but also specimens from irradiated cases.

Cisplatin, vindesine, pepleomycin and combined radiation therapy for inoperable esophageal carcinoma

Sixteen inoperable esophageal cancer patients, including six over 80 years of age, were given combined chemoradiation therapy. The treatment consisted of radiation therapy (50-60 Gy for 6-7 wk on days 1 to 46) combined with cisplatin (50 mg/m2 i.v. on days 22 and 50), vindesine (3 mg/m2 i.v. on days 22 and 50) and pepleomycin (5 mg i.m. on days 23 to 27 and 51 to 55). The treatment was well-tolerated. The overall response rate was 56%, with three complete responses and six partial responses. For 10 patients with loco-regional disease (stage II-III), the response rate was 70%. The overall median survival was 7 mo and the survival rate was 31% at one year and 23% at two years. For loco-regional disease, the one and two-year survival rates were 40 and 27%, respectively, with a median survival of 8 mo. The protocol is worthy of being considered for treating inoperable, poor-risk esophageal cancer patients.

[Structure-activity relationship of flavonoids in suppressing rat liver lipid peroxidation]

145 flavonoids were studied for their inhibitory effects on the iron-induced lipid peroxidation in mitochondria obtained from rat livers. Of these compounds tested, 30, 57, 59, 67, 70, 72, 77, 102 and 110 (ED50 < or = 0.5 nmol/mg prot) showed distinctly more potent inhibitory activity than baicalein (ED50 < or = 5 nmol/mg prot) and 59 and 72 (ED50 < or = 0.05 nmol/mg prot) exhibited the most potent activity. In order to elucidate the relationships between substituents on the flavonoid skeleton and the biological activity, the quantitative structure-activity relationships (QSAR) were analyzed by the adaptive least-squares (ALS) method for 142 flavonoids. The analysis has shown that the presence of the 1,4- and 1,2-hydroquinone in A-ring and/or B-ring of flavonoids and hydrophobicity of the molecule are responsible for the in vitro inhibitory activity.

Prediction of operative mortality based on impairment of host defense systems in patients with esophageal cancer

To determine whether operative risk based on impaired defense systems can be predicted, we examined 21 markers in 32 patients with esophageal cancer seen between 1983 and 1985 and related them to postoperative deaths. A discriminant analysis proved useful in determining whether the patient would be at risk of operative mortality, based on impaired defense systems. This model, the host defense index (HDI), was then used clinically to evaluate findings in 64 patients seen between 1986 and 1991. During this period, a change in policy for performing transthoracic esophagectomy on and perioperative care for patients with impaired defense systems was associated with a decrease in operative mortality. Thus, the HDI is beneficial to predict the risk of operative mortality based on impaired defense systems in patients with esophageal cancer.

Sacral chordoma developing two years after low anterior resection for rectal cancer

A 43-year-old male with sacral chordoma associated with rectal cancer is herein reported. A presacral tumor with extensive destruction of S4 and S5 was found 2.5 years after a low anterior resection for advanced rectal mucinous carcinoma. Under the preoperative diagnosis of a solitary sacral metastasis of rectal cancer, the lower sacral segments together with the tumor were removed by amputation at S3. Histologically, the tumor was a chordoma composed of polyhedral cells with an abundant eosinophilic cytoplasm mixed with typical vacuolated physaliferous cells within a myxoid matrix. Colorectal cancer associated with an extracolic primary malignant neoplasm is not uncommon; however, this is only the second case of colorectal cancer associated with chordoma to the best of our knowledge.

Impaired neutrophil bactericidal activity correlates with the infection occurring after surgery for esophageal cancer

We examined whether or not preoperative impaired bactericidal activities of polymorphonuclear neutrophils (PMN) are associated with infections following surgery for esophageal cancer. Intracellular killing (KI), superoxide anion-producing capacity (SOP), and myeloperoxidase (MPO) activity were measured in 22 patients with esophageal cancer, 27 with gastric cancer, and 13 age-matched controls. The average level of KI was significantly depressed in patients with esophageal cancer or with gastric cancer, to a similar extent, compared to findings in controls, but SOP was not. In esophageal cancer patients, the SOP level was significantly higher in those with postoperative septic complications than in those without such problems, whereas the KI level was depressed to a similar extent in both. Therefore, a depression of KI with elevation of SOP of PMN may serve to predict complications of infection following surgery in patients with esophageal cancer.