Competitive reverse transcription-polymerase chain reaction assay for quantification of human multidrug resistance 1 (MDR1) gene expression in fresh leukemic cells

We have analyzed MDR1 gene expression in 69 clinical samples obtained from 64 patients with leukemic hematologic malignancies by using a competitive reverse transcription-polymerase chain reaction assay with a heterologous competitor RNA. To exclude a false-positive result caused by concomitant normal lymphocytes that physiologically express MDR1, in samples we determined a cut-off value of 8 amol MDR1 transcript per microgram of RNA by simultaneous measurement of rhodamine 123 dye efflux either in lymphocyte or gated leukemic cell populations. Consequently, 23 of 69 samples were concluded to be MDR1-positive in leukemic cells per se. The MDR1 expression rate was significantly correlated with factors such as a history of preceding chemotherapy, elder age of the patient, and certain disease types (eg, leukemia progressed from myelodysplastic syndrome). Moreover, the complete response rate after chemotherapy was significantly higher in MDR1-negative patients than in MDR1-positive patients (52% vs 17%, respectively; P = .01). The assay established will enable the quantification of MDR1 gene expression in blood samples from patients with leukemic hematologic malignancies and will be applicable to clinical laboratories as a routine test.

A high level of physical fitness during thirties is a negative risk factor for colonic polyps during fifties

This case-control study examined the relationship between the occurrence of colonic polyps in men in their fifties and the level of their physical fitness while in their thirties. The subjects consisted of 51 male Japan Self-Defense Forces officials in their fifties who had colonic polyps, as diagnosed by colonoscopic examination, and 46 control individuals. As an indicator of physical fitness between 30 and 39, we selected the best time recorded for each individual during that decade of life for the 1,500 meter Physical Fitness Test run. We calculated the odds ratio for polyps according to selected risk factors (including physical fitness), and a logistic regression analysis was used to adjust for possible confounding variables. Odds ratio (95% confidence interval, p value) for colonic polyps with physical fitness in the thirties was 0.36 (0.16-0.82, p < 0.05). With adjustment for the subjects' maximum Body Mass Index in both their thirties and fifties, and serum total cholesterol, the odds ratio was 0.39 (0.15-0.99, p < 0.05). We suggest that the occurrence of colonic polyps in men in their fifties can be reduced by maintaining a high level of physical fitness while in their thirties.

Stiff-man syndrome associated with antecedent myasthenia gravis and organ-specific autoimmunopathy

We describe a case of stiff-man syndrome accompanied by diabetes mellitus, Hashimoto's thyroiditis and the antecedent myasthenia gravis. The diagnosis of stiff-man syndrome was made based on not only clinical findings and the characteristic electromyographic pattern but also the presence of antibodies to glutamic acid decarboxylase in the serum and cerebrospinal fluid. Stiff-man syndrome is known to be associated with organ-specific autoimmunopathy including insulin-dependent diabetes mellitus. The present case is the first one that stiff-man syndrome was preceded by myasthenia gravis of organ-specific autoimmunopathy. Stiff-man syndrome in the present case probably represents the one of fully expressed manifestations from the broad spectrum of organ-specific autoimmunopathy caused by the loss of self-tolerance.

Triphenyltin chloride induces glucose intolerance by the suppression of insulin release from hamster pancreatic beta-cells

We performed an intravenous glucose tolerance test (IVGTT) after the administration of triphenyltin chloride (TPTCl-Ad) in hamsters in order to confirm the presence of glucose intolerance and to clarify the pathogenesis of TPTCl-induced glucose intolerance. On the 1st, 2nd, 3rd, 4th and 7th days after TPTCl-Ad or the administration of sesame oil alone as a control, glucose was injected at a dose of 0.05 g glucose/100 g B.W., and then PG, IRI and TG were measured on 0, 1, 2, 3, 5 and 10 min after IVGTT. The TPT concentration in the pancreas was measured by gaschromatography and the morphological findings with a transmission electron microscope were compared between the TPTCl-Ad and the control hamsters. FPG on the 1st and the 2nd days after TPTCl-Ad were significantly higher than those in control, but those on the 4th and the 7th day recovered up to the control level. In contrast, basal IRI levels showed reciprocal results compared to the FPG levels. delta IRI/ delta PG on the 1st day after TPTCl-Ad was significantly reduced compared to the control. Fasting TG on the 1st day after TPTCl-Ad was much higher than the control. TPT-concentration on the 1st day after TPTCl-Ad showed peak values and its concentration gradually decreased. Electron microscopic findings in the pancreas after TPTCl-Ad indicated neither destruction nor lymphocyte infiltration of the pancreas.

CONCLUSIONS

The present data suggest that the administration of TPTCl in hamsters induces a functional transient damage on islet cells but not a morphological disorder, which shows an essentially different nature from the change in the pancreas induced by viral infection or by a large amount of streptozotocin.

Characteristics and clinical outcomes in pituitary incidentalomas and non-incidental pituitary tumors treated with endoscopic transsphenoidal surgery

PURPOSE

In this retrospective study, we investigated the status and validity of endoscopic transsphenoidal surgery (eTSS) for pituitary incidentalomas (PIs) as well as the value of basing the indication for surgery on the PI guidelines.

METHODS

Patients who underwent eTSS at Fukuoka University Chikushi Hospital between 2012 and 2018 were divided into the PI group and the non-PI group in accordance with the PI guideline of the Endocrine Society and their clinicopathological characteristics and outcomes were compared and analyzed.

RESULTS

A total of 59 patients were enrolled, with 35 patients in the PI group and 24 patients in the non-PI group. The diagnoses in the PI group were of non-functioning pituitary adenoma (NFPA) (n = 12, 34%), gonadotropin-producing pituitary adenoma (n = 8, 23%), Rathke cleft cyst (n = 7, 20%), meningioma (n = 4, 11%), and growth hormone-producing pituitary adenoma (n = 3, 9%); those in the non-PI group were of NFPA (n = 6, 25%), gonadotropin-producing pituitary adenoma (n = 3, 13%), Rathke cleft cyst (n = 3, 13%), growth hormone-producing pituitary adenoma (n = 3, 13%), and prolactin producing pituitary adenoma (n = 3, 13%). Regarding the preoperative factors, 1 patient in the PI group with panhypopituitarism was diagnosed with pituitary apoplexy (pure infarction) of an NFPA. The rates of postoperative anterior pituitary hormonal deficiencies (14% vs 46%, P = .015), residual tumor size (2 ± 5 vs 6 ± 7 mm, P = .008), and reoperation (n = 0, 0% vs n = 5, 21%, P = .005) were significantly different between the PI and non-PI groups.

CONCLUSIONS

This study showed that, postoperatively, the incidence of anterior pituitary hormonal deficiencies was lower in the PI than in the non-PI group, although it was comparable between the 2 groups before the operation. The patients in the PI group also had smaller residual tumors and a lower risk of reoperation than those in non-PI group. PIs could have a better postoperative clinical outcome than non-PIs when the indication for eTSS is based on preoperative scrutiny according to the PI guidelines and eTSS is performed by an experienced pituitary surgeon. Hence, more aggressive scrutiny and treatment for PIs might be desirable.

A case of relapsing polychondritis associated with hemolytic anemia

Relapsing Polychondritis (RPC) is a rare disorder of unknown etiology which affects mucopolysaccharide-rich tissues such as cartilage. A 64-year-old man developed auricular and nasal chondritis with complaints of arthralgia of the hands and cervical pain. The auricular biopsy established the diagnosis of RPC. The hematological data revealed normocytic, slightly hypochromic anemia, a persistently elevated reticulocyte count, slightly increased bilirubin, and decreased haptoglobin. The presence of hemolytic anemia was confirmed by the shortened half-life of erythrocytes and erythroid hyperplasia of the bone marrow. This case illustrates the coexistence of RPC and hemolytic anemia which has been only rarely reported. The pathogenesis of RPC is also discussed may elucidate the pathogenesis of this disease.

A cross-sectional study on the relationship between depression and left ventricular hypertrophy

BACKGROUND

Despite a large number of studies, the relationship between depression and cardiovascular disease remains ambiguous. This study is the first to investigate the relationship between depression and left ventricular hypertrophy (LVH) as detected by electrocardiogram.

METHODS

The subjects were 346 male Japan Self-Defense Forces personnel ages 49 to 55 years. LVH was assessed by electrocardiogram. Depression was measured by the Self-Rating Depression Scale (SDS). Other selected risk factors were measured. Odds ratios for LVH in relation to selected variables were calculated. A logistic regression analysis was used to adjust for possible confounding variables.

RESULTS

High level of depression (SDS score > or = 34) showed a high risk of LVH occurrence. After adjusting for BMI, systolic blood pressure, and/or diastolic blood pressure, there was a tendency toward a positive association of LVH with high level of depression.

CONCLUSIONS

Our present study demonstrated that depression is closely related to LVH. Since LVH could be a predictor of fatal cardiovascular disease, this is of direct relevance to the prescription of preventive measures.

Differential alterations of dihydrofolate reductase gene in human leukemia cell lines made resistant to various folate analogues

In order to clarify a molecular mechanism of folate resistance in leukemia cells, we studied alterations of the dihydrofolate reductase (DHFR) gene in a human leukemia cell line, MOLT-3, and its sublines made resistant to methotrexate (MTX), trimetrexate (TMQ) and N10-propargyl-5,8-dideazafolic acid (CB3717), alone or in combination. Major alterations of the DHFR gene were examined by Southern analysis of high-molecular-weight DNA. The presence of a base change (T-->C) at nucleotide position 91 of the DHFR gene, which is reported to be responsible for the reduced affinity of the enzyme for MTX in an MTX-resistant human colon carcinoma cell, was examined by allele-specific oligonucleotide hybridization. In a 10,000-fold MTX-resistant subline (MOLT-3/MTX10,000), the normal allele of DHFR gene had been amplified. In contrast, a 200-fold TMQ-resistant subline (MOLT-3/TMQ200) and a 30-fold CB3717-resistant subline selected from MOLT-3/TMQ200 (MOLT-3/TMQ200-CB-3717(30)) were shown to have the mutant allele. Furthermore, the mutant allele had been amplified in a 500-fold MTX-resistant subline, which was established by the continuous exposure of the MOLT-3/TMQ200 cells to stepwise increases of drug concentration and designated as MOLT-3/TMQ200-MTX500. On the other hand, a 40-fold-resistant subline to CB3717 alone (MOLT-3/CB3717(40)) showed the normal allele without amplification. These data suggest that complex alterations of the DHFR gene are involved in the molecular mechanisms of folate resistance that can be differentially introduced into leukemia cells by exposure to various folate analogues, alone or in combination.

'Transfer out' tuberculosis patients: treatment outcomes after cross-checking registers, 2012-2013, Lusaka, Zambia

SETTING

Lusaka, Zambia.

OBJECTIVE

To assess the actual treatment outcomes of 'transfer out' (TO) cases at a diagnostic centre in Lusaka, in the third and fourth quarters of 2012, and to see the impact of this cross-check in treatment success rates (TSR) in 2013 and early 2014.

DESIGN AND METHOD

In this retrospective cohort study, treatment outcomes for new bacteriologically positive tuberculosis (TB) cases referred from the diagnostic centre were reviewed and compared with those at the receiving treatment units.

RESULTS

Of 49 (58%) cases referred to three treatment units, the treatment outcomes of nine had to be updated at the diagnostic centre, which reduced the proportion of TO cases from 17.6% to 11.8% and increased the TSR to 70.6% from 64.7%.

CONCLUSION

The review and cross-checking of the TB registers at the diagnostic and treatment units led to a significant reduction in non-assessed cases, suggesting that the TB registers in the diagnostic and treatment units should be cross-checked regularly. There is also need for a complementary intervention to reduce the proportion of TOs associated with high loss to follow-up and non-evaluated TO rates.

Safety of direct oral anticoagulant - and antiplatelet therapy in patients with atrial fibrillation treated by carotid artery stenting

BACKGROUND

The periprocedural administration of dual antiplatelet therapy has been recommended in patients treated by carotid artery stenting. However, some patients with concurrent disease have been prescribed anticoagulants. We compared the post-operative incidence of hemorrhagic and thromboembolic events in two patient groups treated by different regimens of multi-antithrombotic agents.

METHODS

As our 31 patients had a history of nonvalvular atrial fibrillation, they had received anticoagulants; they were also treated with aspirin and clopidogrel before carotid artery stenting. The prior anticoagulant therapy was continued in 17 patients and they received vitamin K antagonist plus dual antiplatelet therapy after the procedure (group 1). Other 14 patients underwent direct oral anticoagulant plus aspirin or clopidogrel (group 2). Post-procedural hemorrhagic and thromboembolic events were compared between two groups.

RESULTS

Carotid artery stenting was angiographically successful in all patients. Complications were encountered in two group 1 patients. Post-operative image revealed a silent subarachnoid hemorrhage in one. The other presented with superior mesenteric artery occlusion 6 months after the procedure. No hemorrhagic or thromboembolic events occurred in group 2.

CONCLUSION

We concluded that the administration of a direct oral anticoagulant plus an antiplatelet agent reduced the risk for periprocedural hemorrhagic and embolic events in patients with concurrent nonvalvular atrial fibrillation who underwent carotid artery stenting.

Ten-year follow-up study of thyroid function in euthyroid patients with simple goiter or Hashimoto's thyroiditis

In an attempt to study the natural course of Hashimoto's thyroiditis and simple goiter, 74 euthryroid patients with Hashimoto's thyroiditis and 212 patients with simple goiter were followed for 10 years. In 204 patients with simple goiter (96.2%) it remained as a simple goiter throughout the observation period, whereas 8 patients (3.8%) later had Hashimoto's thyroiditis as evidenced by the appearance of circulating thyroid autoantibodies. These 8 patients had HLA typing significantly different from that of control subjects. None of the patients with simple goiter had hyperthyroid Graves' disease despite the fact that 17.5% of those patients had mild to moderate exophthalmos with either Moebius' sign or von Graefe's sign. In contrast, 12 patients with Hashimoto's thyroiditis (16.2%) had exophthalmos with Moebius' sign and/or von Graefe's sign, and 4 of 12 such patients later had hyperthyroid Graves' disease. TSH binding inhibitory immunoglobulin was detected in 3 of 4 such patients with hyperthyroid Graves' disease. Forty-nine patients with Hashimoto's thyroiditis (66.2%) still remained euthyroid but 20 of those (27.0%) turned into hypothyroidism during the 10-year follow-up.

Ruptured tectal arteriovenous malformation demonstrated angiographically after removal of an unruptured occipital lobe arteriovenous malformation

We report a case of ruptured tectal arteriovenous malformation (AVM) that was demonstrated angiographically only after removal of an unruptured occipital AVM. A 57-year-old man presented with sudden onset of diplopia and tinnitus. Computed tomography revealed a small hemorrhage in the right tectum mesencephali with intraventricular hemorrhage. Magnetic resonance imaging and angiography disclosed AVM in the right occipital lobe which was separate from the hemorrhagic lesion. Angiography demonstrated that the right occipital AVM was fed by the parieto-occipital artery and drained into the superior sagittal sinus and vein of Galen. However, no abnormal vascular lesion was detected near the tectum mesencephali. As venous hypertension was considered the reason for hemorrhage, the occipital AVM was completely resected. Postoperative angiography demonstrated disappearance of the occipital AVM, but it also disclosed a small tectal AVM fed by branches from the superior cerebellar artery, which had not been detected on preoperative angiography. This was considered the true cause of hemorrhage, and gamma knife surgery was accordingly performed. Even if an AVM is demonstrated, if the lesion does not correspond to the hemorrhage we recommend serial angiographical evaluation so that a small AVM is not missed.

Examination of the characteristics of long-term survivors among patients with gallbladder cancer with liver metastasis who underwent surgical treatment: a retrospective multicenter study (ACRoS1406)

Background

Gallbladder cancer (GBC) with liver metastasis is considered unresectable. However, there have been infrequent reports of long-term survival in patients with GBC and liver metastases. Therefore, we examined the characteristics of long-term survivors of gallbladder cancer with liver metastasis.

Methods

A retrospective multicenter study of 462 patients with GBC (mean age, 71 years; female, 51%) was performed. Although patients with pre-operatively diagnosed GBC and liver metastasis were generally excluded from resection, some cases identified during surgery were resected.

Result

In patients with resected stage III/IV GBC (n = 193), the period 2007–2013 (vs. 2000–2006, hazard ratio 0.63), pre-operative jaundice (hazard ratio 1.70), ≥ 2 liver metastases (vs. no liver metastasis, hazard ratio 2.11), and metastasis to the peritoneum (vs. no peritoneal metastasis, hazard ratio 2.08) were independent prognostic factors for overall survival, whereas one liver metastasis (vs. no liver metastasis) was not. When examining the 5-year overall survival and median survival times by liver metastasis in patients without peritoneal metastasis or pre-operative jaundice, those with one liver metastasis (63.5%, not reached) were comparable to those without liver metastasis (40.4%, 33.0 months), and was better than those with ≥ 2 liver metastases although there was no statistical difference (16.7%, 9.0 months). According to the univariate analysis of resected patients with GBC and liver metastases (n = 26), minor hepatectomy, less blood loss, less surgery time, papillary adenocarcinoma, and T2 were significantly associated with longer survival. Morbidity of Clavien–Dindo classification ≤ 2 and received adjuvant chemotherapy were marginally not significant. Long-term survivors (n = 5) had a high frequency of T2 tumors (4/5), had small liver metastases near the gallbladder during or after surgery, underwent minor hepatectomy without postoperative complications, and received postoperative adjuvant chemotherapy.

Conclusions

Although there is no surgical indication for GBC with liver metastasis diagnosed pre-operatively, minor hepatectomy and postoperative chemotherapy may be an option for selected patients with T2 GBC and liver metastasis identified during or after surgery who do not have other poor prognostic factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02234-9.

Association between alcohol intake and subjective health: the Sotetsu Study

Subjective health and alcohol intake are important predictors of mortality. There have been few epidemiological studies, however, of the relationship between alcohol consumption and subjective health among the Japanese. The purpose of this study is to investigate the association between alcohol consumption and subjective health. The study subjects were 2,020 Japanese male employees, who were free from serious disease conditions. The data on subjective health and alcohol consumption were obtained by means of self-reported questionnaire. The subjects who responded "poor health" in the answer to the question about the subjective health status were considered to be in ill-health. Ethanol intake per day was calculated by multiplying the frequency of drinking by the ethanol intake per drinking occasion and summing up for each alcoholic beverage. Age, smoking status, physical activity, and sleeping hours were treated as confounding factors. As a result, subjects who consumed 25-36 or 49 g ethanol or more per day had a significantly lower risk of self-rated ill-health compared with those who had never drunk, and a significantly inverse trend was found independent of age, smoking status, physical activity, and sleeping hours. In conclusion, moderate drinkers have a lower risk of self-rated ill-health among Japanese male employees investigated.

Microsatellite instability and clonal heterogeneity of MDR1 messenger RNA expression in trimetrexate-resistant human leukemia MOLT-3 cells developed in thymidine

Various gene alterations are involved in the drug resistance of leukemia cells. To understand the mechanism that underlies the emergence of cells with such gene alterations in human leukemia, we performed clonal analysis of the gene expression of mutant dihydrofolate reductase (DHFR) and mdr1 in trimetrexate-resistant human leukemia MOLT-3 cells. Trimetrexate-resistant (70- and 60-fold) sublines were developed in the presence or absence of an exogenous supply of thymidine (MOLT-3/TMQ70/Th+, MOLT-3/TMQ60/Th-, respectively). Ten clonal lines were isolated by methyl cellulose cloning from each of the 2 trimetrexate-resistant MOLT-3 sublines. All the clonal lines from the 2 sublines expressed mutated DHFR mRNA, with a base change (T --> C) at the second position of codon 31, as well as the wild-type mRNA, in accordance with cross-resistance to methotrexate. On the other hand, mdr1 mRNA expression was demonstrated by reverse-transcription polymerase chain reaction only in clonal lines from MOLT-3/TMQ70/Th+ cells. mdr1 mRNA expression in clonal lines from MOLT-3/TMQ70/Th+ cells and subclonal lines subsequently obtained from the 3 clonal lines with different mdr1 mRNA expression levels was heterogeneous, and its high expression levels were correlated with acquisition of the multidrug resistance (MDR) phenotype. Polymerase chain reaction-based assay for separate microsatellites, mfd27 and mfd41, demonstrated genomic instability among clonal and subclonal lines of MOLT-3. The clonal analysis of polymorphic microsatellites also suggested that emergence of MDR in trimetrexate-resistant MOLT-3 cells in thymidine was not only heterogeneous but also progressively expanding among clones. Genomic instability may play a role in the establishment and clonal evolution of drug resistance in leukemia cells.

Application of the new zinc-62/copper-62 generator: an effective labeling method for 62Cu-PTSM

A potential PET flow tracer, 62Cu-labeled pyruvaldehyde bis(N4-methylthiosemicarbazone) (62Cu-PTSM), was prepared using a new 62Zn/62Cu generator. With this 62Cu-labeling method based on a ligand exchange reaction, 62Cu-PTSM was quantitatively obtained by simple mixing of the generator eluate, 62Cu-glycine and PTSM solution for a few seconds. The glycine contained in the 62Cu-PTSM injectate had no significant effect in mouse biodistribution studies. The PET studies of 62Cu-PTSM showed brain images that were not visualized by 62Cu-labeled albumin (a plasma pool tracer), in the dog cranium.

Development of glycoside-bound radiopharmaceuticals: novel radioiodination method for digoxin

We combined 2-hydroxy-3-methylbenzoylhydrazide (HMBH) with glycosides as a novel method for the radioiodination of physiologically active glycosides. This method was tested using digoxin, which is one of the cardiac glycosides. A digoxin-HMBH conjugate was synthesized by periodate cleavage of the third sugar ring, and was readily radiolabeled with Na[125I] by the chloramine-T method. 125I labelled digoxin-HMBH conjugate retained Na+, K(+)-ATPase binding in vivo and in vitro, and also retained immunoreactivity to an anti-digoxin antibody. Thus, this 125I labelled digoxin-HMBH conjugate represents a potential radiopharmaceutical for Na+, K(+)-ATPase imaging, as well as for the radioimmunoassay of digoxin.

Cytotoxicity of trimetrexate against antifolate-resistant human T-cell leukemia cell lines developed in oxidized or reduced folate

Cytotoxicity of trimetrexate (TMQ), a lipophilic dihydrofolate reductase inhibitor, was examined in antifolate-resistant human T-cell leukemia cell lines developed in oxidized or reduced folate. An approximately 60-fold methotrexate (MTX)-resistant subline was developed in oxidized folate (pteroylglutamic acid: PGA) (CCRF-CEM/MTX60-PGA) from human T-cell leukemia cell line CCRF-CEM; this line exhibited impaired membrane transport of the drug. Further enhancement of MTX resistance resulted in selection of an approximately 5000-fold MTX-resistant subline (CCRF-CEM/ MTX5000-PGA), which showed increased dihydrofolate reductase activity due to gene amplification in addition to further impairment of MTX transport. An approximately 140-fold MTX-resistant subline, and then a 1500-fold MTX-resistant subline were developed in reduced folate (10 nM leucovorin) (CCRF-CEM/MTX140-LV and CCRF-CEM/MTX1500-LV); they exhibited increased dihydrofolate reductase due to gene amplification accompanied by increased intracellular drug accumulation of MTX. While CCRF-CEM/MTX140-LV and CCRF-CEM/MTX1500-LV cells showed cross-resistance to TMQ, CCRF-CEM/MTX60-PGA and CCRF-CEM/MTX5000-PGA cells were at least as sensitive to TMQ as the parent cells. TMQ was more potent against approximately 200-fold N10-propargyl-5,8-dideazafolic-acid (CB3717)-resistant human T-cell leukemia MOLT-3 sublines developed in PGA (MOLT-3/CB3717(200)-PGA) or leucovorin (MOLT-3/CB3717(200)-LV), as compared to the parent cells; MOLT-3/CB3717(200)-PGA and MOLT-3/CB3717(200)-LV cells were resistant to CB3717 by virtue of impaired transport, only the former possessing gene amplification of thymidylate synthase. The cytotoxicity of TMQ in both MOLT-3/CB3717(200)-PGA and MOLT-3/CB3717(200)-LV cells was reduced by addition of leucovorin in a dose-dependent manner, suggesting intracellular folate deficiency as a cause of TMQ sensitivity. These results demonstrate that TMQ overcomes transport-impaired antifolate resistance, irrespective of gene amplification of dihydrofolate reductase or thymidylate synthase. Types of folate used during the development of antifolate resistance seem to be important in relation to the mechanism of TMQ responsiveness as well as that of antifolate resistance.

Biological activity and intracellular metabolism of ZD1694 in human leukemia cell lines with different resistance mechanisms to antifolate drugs

The biological activity and cellular metabolism of ZD1694, a novel folate-based thymidylate synthase (TS) inhibitor, were analyzed in a human leukemia cell line, MOLT-3, and its antifolate-resistant sublines with different mechanisms of resistance to methotrexate (MTX), trimetrexate (TMQ) and N10-propargyl-5,8-dideazafolic acid (CB3717). MOLT-3/CB3717(40), which was selected for CB3717 resistance, demonstrated impaired membrane drug transport via reduced folate carrier (RFC) and lower accumulation of [3H]ZD1694-polyglutamates in the cells with a shift in the polyglutamate distribution profile to shorter chain length polyglutamates, indicating an alteration in polyglutamation capacity in this subline. Impaired RFC and reduced rate of polyglutamation could explain the cross-resistance (12-fold) of this subline to ZD1694. On the other hand, there was little or no cross-resistance to this drug in a subline (MOLT-3/TMQ800) reportedly resistant to TMQ through impaired membrane transport for TMQ and an increase in dihydrofolate reductase (DHFR) activity. Total amount of ZD1694 polyglutamated to a level higher than diglutamate was approximately 1.7-fold higher in the TMQ-resistant cells than that in the parent cells, but a low degree of increase in TS activity in the cells counteracted the supposed increase in sensitivity to ZD1694. MOLT-3/TMQ800-MTX10000 cells, which were established by sequential exposure of the TMQ-resistant cells to MTX and were previously shown to amplify mutated DHFR with low affinity for MTX, showed a decreased accumulation of polyglutamated ZD1694 as compared with the parent line and this was consistent with cross-resistance to ZD1694 in this subline. Overproduction of variant DHFR scarcely influenced the sensitivity to this drug. These results indicate that ZD1694 could overcome antifolate resistance through a mechanism such as amplified DHFR activity, and the biological activity of this drug against the cells paralleled the amount of polyglutamated drug inside the cells. Determination of polyglutamation capacity in tumor cells may allow prediction of sensitivity to this drug.

Gamma-synuclein is a novel prognostic marker that promotes tumor cell migration in biliary tract carcinoma

Gamma‐synuclein (SNCG) promotes invasive behavior and is reportedly a prognostic factor in a range of cancers. However, its role in biliary tract carcinoma (BTC) remains unknown. Consequently, we investigated the clinicopathological significance and function of SNCG in BTC. Using resected BTC specimens from 147 patients with adenocarcinoma (extrahepatic cholangiocarcinoma [ECC, n = 96]; intrahepatic cholangiocarcinoma [ICC, n = 51]), we immunohistochemically evaluated SNCG expression and investigated its correlation with clinicopathological factors and outcomes. Furthermore, cell lines with high SNCG expression were selected from 16 BTC cell lines and these underwent cell proliferation and migration assays by siRNAs. In the results, SNCG expression was present in 22 of 96 (22.9%) ECC patients and in 10 of 51 (19.6%) ICC patients. SNCG expression was significantly correlated with poorly differentiated tumor in both ECC and ICC (p = 0.01 and 0.03, respectively) and with perineural invasion and lymph node metastases in ECC (p = 0.04 and 0.003, respectively). Multivariate analyses revealed that SNCG expression was an independent poor prognostic factor in both OS and RFS in both ECC and ICC. In vitro analyses showed high SNCG expression in three BTC cell lines (NCC‐BD1, NCC‐BD3, and NCC‐CC6‐1). Functional analysis revealed that SNCG silencing could suppress cell migration in NCC‐BD1 and NCC‐CC6‐1 and downregulate cell proliferation in NCC‐CC6‐1 significantly. In conclusion, SNCG may promote tumor cell activity and is potentially a novel prognostic marker in BTC.

Nephrotic syndrome associated with generalized amyloidosis and IgM-monoclonal proteinemia

A 67-year-old woman was admitted for nephrotic syndrome. In spite of the lack of lymphadenopathy, hepatosplenomegaly and serum hyperviscosity, remarkable monoclonal IgM-proteinemia was demonstrated. Amyloid kidney was shown by renal biopsy. However, in the bone marrow and other organs, neither proliferation nor invasion of monoclonal immunoglobulin-producing cells was revealed by immunohistological investigations of the specimens biopsied or examined at autopsy, excluding Waldenström's macroglobulinemia. Immunosuppressive chemotherapy with cyclophosphamide, vincristine and prednisolone was effective in reducing serum IgM, but could not slow the progression of renal failure. This case suggested the association of generalized amyloidosis with excessive IgM-proteinemia caused by a non-malignant mechanism.

A case of postnephrectomy arteriovenous fistula

A rare case of a postnephrectomy arteriovenous fistula involving the major renal vessels is presented herein. This type of postnephrectomy arteriovenous fistula is very unusual; in fact, since first documented in 1934, only 65 cases have been reported in the world literature, including 2 cases from Japan. Even though postoperative arteriovenous fistulae are rare, one should bear this complication in mind when unknown causes of bruit or heart failure develop following surgery.