EV-miRome-wide profiling uncovers miR-320c for detecting metastatic colorectal cancer and monitoring the therapeutic response

PURPOSE

Molecular composition of circulating small extracellular vesicles (EVs) does not merely reflect the cells of origin, but also is enriched in specific biomolecules directly associated with the cellular transformation. However, while most of the currently identified EV-miRs are only geared towards one-dimensional disease detection, their application for long-term tracking and treatment response monitoring has been largely elusive.

METHODS

We established and optimized a rapid, sensitive and robust liquid biopsy sampling method, and further used small RNA sequencing to comprehensively catalogue EV-miRomes in association with the progression and outcome of metastatic colorectal cancer (mCRC).

RESULTS

By cross-comparison of EV-miRomes (n = 290) from multi-stage and longitudinal cohorts, we uncovered a 15-EV-miR signature with dual detection and long-term monitoring of tumor size progression for mCRC. From this panel, EV-miR-320c was uncovered as a strong clinical marker - aside from its diagnostic power and a therapeutic monitoring performance superior to carcinoembryonic antigen (CEA), its high expression has also been linked to lower overall survival and a greater likelihood of disease recurrence. Further, integrative analyses of tissue transcriptomic and liquid biopsy implicated this 15-EV-miR signature in programming the mesenchymal-epithelial transition (MET) for distant localization of the metastasized cells and also in creating a tumor-favoring metastatic niche.

CONCLUSION

Our clinically-oriented delineation of the mCRC-associated circulating EV-miRomes systematically revealed the functional significance of these liquid biopsy markers and further strengthen their translational potential in mCRC therapeutic monitoring.

A novel antisense RNA ASPACT confers multi-level suppression of PACT and associated signalling

The innate immune system is the frontline host protection against pathogens. Effective antiviral immunity is elicited upon recognition of viral RNAs by the host pattern recognition receptors. One of the major viral RNA sensors is retinoic acid inducible gene-1, which triggers the production of interferons (IFNs). In turn, this protective response requires another viral sensor and immunity factor interferon-inducible protein kinase RNA activator (PACT/PRKRA). Here, we report the identification and characterization of a novel antisense PACT gene that expresses a non-coding RNA in a convergent and interferon-inducible manner. Publicly available gene structure and expression data revealed that this gene, that we termed ASPACT, overlaps with the 3' -end of the PACT locus and is highly expressed during viral infection. Our results confirm the IFN-β-inducibility of ASPACT, which is dependent on STAT-1/2. We further discovered that downregulation of ASPACT impacts both the expression and localization of the PACT transcript. At the transcription level, ChIP and ChIRP assays demonstrated that the ASPACT non-coding RNA occupies distinct chromatin regions of PACT gene and is important for promoter recruitment of the epigenetic silencer HDAC1. In parallel, ASPACT was also found to mediate nuclear retention of the PACT mRNA via direct RNA-RNA interaction, as revealed by RNA antisense purification assay. In summary, our results support the model that the non-coding RNA ASPACT acts as a negative regulator of PACT at multiple levels, and reveal a novel regulator of the viral counteractive response.

ADAR1 promotes robust hypoxia signaling via distinct regulation of multiple HIF-1α-inhibiting factors

Adenosine deaminase acting on RNA (ADAR)-catalyzed adenosine-to-inosine RNA editing is potentially dysregulated in neoplastic progression. However, how this transcriptome recoding process is functionally correlated with tumorigenesis remains largely elusive. Our analyses of RNA editome datasets identify hypoxia-related genes as A-to-I editing targets. In particular, two negative regulators of HIF-1A-the natural antisense transcript HIF1A-AS2 and the ubiquitin ligase scaffold LIMD1-are directly but differentially modulated by ADAR1. We show that HIF1A-AS2 antagonizes the expression of HIF-1A in the immediate-early phase of hypoxic challenge, likely through a convergent transcription competition in cis ADAR1 in turn suppresses transcriptional progression of the antisense gene. In contrast, ADAR1 affects LIMD1 expression post-transcriptionally, by interfering with the cytoplasmic translocation of LIMD1 mRNA and thus protein translation. This multi-tier regulation coordinated by ADAR1 promotes robust and timely accumulation of HIF-1α upon oxygen depletion and reinforces target gene induction and downstream angiogenesis. Our results pinpoint ADAR1-HIF-1α axis as a hitherto unrecognized key regulator in hypoxia.

Tumor-associated intronic editing of HNRPLL generates a novel splicing variant linked to cell proliferation

Processing of the eukaryotic transcriptome is a dynamic regulatory mechanism that confers genetic diversity, and splicing and adenosine to inosine (A-to-I) RNA editing are well-characterized examples of such processing. Growing evidence reveals the cross-talk between the splicing and RNA editing, but there is a paucity of substantial evidence for its mechanistic details and contribution in a physiological context. Here, our findings demonstrate that tumor-associated differential RNA editing, in conjunction with splicing machinery, regulates the expression of variants of HNRPLL, a gene encoding splicing factor. We discovered an HNRPLL transcript variant containing an additional exon 12A (E12A), which is a substrate of ADAR1 and ADAR2. Adenosine deaminases acting on RNA (ADAR) direct deaminase-dependent expression of the E12A transcript, and ADAR-mediated regulation of E12A is largely splicing-based, and does not affect the stability or nucleocytoplasmic distribution of the transcript. Furthermore, ADAR-mediated modification of exon 12A generates an enhancer for the oncogenic splicing factor SRSF1 and consequently promotes the frequency of alternative splicing. Gene expression profiling by RNA-seq revealed that E12A acts distinctly from HNRPLL and regulates a set of growth-related genes, such as cyclin CCND1 and growth factor receptor TGFBR1 Accordingly, silencing E12A expression leads to impaired clonogenic ability and enhanced sensitivity to doxorubicin, thus highlighting the significance of this alternative isoform in tumor cell survival. In summary, we present the interplay of RNA editing and splicing as a regulatory mechanism of gene expression and also its physiological relevance. These findings extend our understanding of transcriptional dynamics and provide a mechanistic explanation to the link of RNA editors to tumorigenesis.

The PPARγ-SETD8 axis constitutes an epigenetic, p53-independent checkpoint on p21-mediated cellular senescence

Cellular senescence is a permanent proliferative arrest triggered by genome instability or aberrant growth stresses, acting as a protective or even tumor‐suppressive mechanism. While several key aspects of gene regulation have been known to program this cessation of cell growth, the involvement of the epigenetic regulation has just emerged but remains largely unresolved. Using a systems approach that is based on targeted gene profiling, we uncovered known and novel chromatin modifiers with putative link to the senescent state of the cells. Among these, we identified SETD8 as a new target as well as a key regulator of the cellular senescence signaling. Knockdown of SETD8 triggered senescence induction in proliferative culture, irrespectively of the p53 status of the cells; ectopic expression of this epigenetic writer alleviated the extent doxorubicin‐induced cellular senescence. This repressive effect of SETD8 in senescence was mediated by directly maintaining the silencing mark H4K20me1 at the locus of the senescence switch gene p21. Further in support of this regulatory link, depletion of p21 reversed this SETD8‐mediated cellular senescence. Additionally, we found that PPARγ acts upstream and regulates SETD8 expression in proliferating cells. Downregulation of PPARγ coincided with the senescence induction, while its activation inhibited the progression of this process. Viewed together, our findings delineated a new epigenetic pathway through which the PPARγ‐SETD8 axis directly silences p21 expression and consequently impinges on its senescence‐inducing function. This implies that SETD8 may be part of a cell proliferation checkpoint mechanism and has important implications in antitumor therapeutics.

A 17-billion-solar-mass black hole in a group galaxy with a diffuse core

Quasars are associated with and powered by the accretion of material onto massive black holes; the detection of highly luminous quasars with redshifts greater than z = 6 suggests that black holes of up to ten billion solar masses already existed 13 billion years ago. Two possible present-day 'dormant' descendants of this population of 'active' black holes have been found in the galaxies NGC 3842 and NGC 4889 at the centres of the Leo and Coma galaxy clusters, which together form the central region of the Great Wall--the largest local structure of galaxies. The most luminous quasars, however, are not confined to such high-density regions of the early Universe; yet dormant black holes of this high mass have not yet been found outside of modern-day rich clusters. Here we report observations of the stellar velocity distribution in the galaxy NGC 1600--a relatively isolated elliptical galaxy near the centre of a galaxy group at a distance of 64 megaparsecs from Earth. We use orbit superposition models to determine that the black hole at the centre of NGC 1600 has a mass of 17 billion solar masses. The spatial distribution of stars near the centre of NGC 1600 is rather diffuse. We find that the region of depleted stellar density in the cores of massive elliptical galaxies extends over the same radius as the gravitational sphere of influence of the central black holes, and interpret this as the dynamical imprint of the black holes.

Functional Impact of RNA editing and ADARs on regulation of gene expression: perspectives from deep sequencing studies

Cells regulate gene expression at multiple levels leading to a balance between robustness and complexity within their proteome. One core molecular step contributing to this important balance during metazoan gene expression is RNA editing, such as the co-transcriptional recoding of RNA transcripts catalyzed by the adenosine deaminse acting on RNA (ADAR) family of enzymes. Understanding of the adenosine-to-inosine RNA editing process has been broadened considerably by the next generation sequencing (NGS) technology, which allows for in-depth demarcation of an RNA editome at nucleotide resolution. However, critical issues remain unresolved with regard to how RNA editing cooperates with other transcript-associated events to underpin regulated gene expression. Here we review the growing body of evidence, provided by recent NGS-based studies, that links RNA editing to other mechanisms of post-transcriptional RNA processing and gene expression regulation including alternative splicing, transcript stability and localization, and the biogenesis and function of microRNAs (miRNAs). We also discuss the possibility that systematic integration of NGS data may be employed to establish the rules of an “RNA editing code”, which may give us new insights into the functional consequences of RNA editing.

Are halos of collisionless cold dark matter collisionless?

We study whether gravitational scattering of halo dark matter particles by subhalos can connect two seemingly independent problems: the abundance of subhalos in dark matter halos and the cuspiness of the halos' inner density profiles. Our numerical experiments indicate that subhalos can cause the collisionless dark matter particles in the centers of main halos to diffuse. Combined with tidal mass loss of the subhalos, this process introduces significant scatter in the inner density profiles and offers an explanation for the range of profiles seen in both observations and cosmological simulations.

Patient Acceptance of Self-Sampling for Human Papillomavirus in Rural China

OBJECTIVE.: To test a new survey instrument and determine the acceptance and potential barriers of cervicovaginal self-sampling for high-risk human papillomavirus in rural Chinese women. MATERIALS AND METHODS.: Data from thirteen survey questions assessed acceptance of the self-sampling procedure. Pain, comprehension, and cultural beliefs were potential barriers evaluated by the survey. RESULTS.: A total of 1,560 women were surveyed. The average and mode number of steps of the self-sampling procedure recalled was 5 (out of 7). Ninety-one percent preferred performing the test at a clinic versus their home. The major barrier encountered was related to the educational level of the women. CONCLUSIONS.: The measure performed well in this population. The self-collection brush was well accepted by these women. Education is the largest hurdle to overcome in implementing a self-sampling screening program.

Nonlinear kinetic Sunyaev-Zeldovich effect

We derive fully nonlinear expressions for temperature fluctuations from the kinetic Sunyaev-Zeldovich (SZ) effect, the scattering of cosmic microwave background photons off hot electrons in bulk motion. Our result reproduces the Ostriker-Vishniac effect to second order in perturbation theory but contains nonlinear corrections to the electron velocities and densities that were neglected previously. We use the recently developed halo model for nonlinear gravitational clustering to compute the nonlinear kinetic SZ power spectrum, which dominates the primary anisotropy on small angular scales.

The onset of nonlinearity in cosmological structure

We discuss the progression of growth of cosmological structure, from the quasilinear evolution of nearly Gaussian fluctuations on large scales into highly non-Gaussian, strongly nonlinear structure on small scales. A systematic development in perturbation theory describes the first departures from homogeneity but fails to reproduce the fully nonlinear results. Physical insight, conceptual models, and symmetries are useful in the strong clustering regime. A phenomenological model with input information from the quasilinear regime provides enticing results for the strongly nonlinear regime.

Verapamil modulation of multidrug resistance in renal cell carcinoma

BACKGROUND AND PURPOSE

Renal cell carcinoma (RCC) is well known for its chemoresistance. The membranous p-glycoprotein (gp-170) is believed to be highly correlated with multidrug resistance (MDR) of cancer cells with energy-dependent pumping efflux of anticancer drugs. Verapamil, a calcium antagonist, inhibits the efflux function of gp-170 and cytoskeletal transportation. The aim of this study was to determine the effect of verapamil on gp-170 expression and intracellular drug accumulation in RCC tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines by verapamil.

METHODS

Using cultured cell lines of RCC and their MDR sublines as target cells, the effect of verapamil on gp-170 expression was analyzed by immunofluorescence flow cytometry. The influence of verapamil on intracellular drug accumulation in RCC tumor cells was measured by autofluorescence flow cytometry. The modulation of verapamil on cytotoxicity of various chemotherapeutic drugs on native RCC cell lines and acquired MDR sublines was analyzed by the methyl tetrazolium method.

RESULTS

From flow cytometric measurement, the expression of gp-170 was significantly decreased in A704 and Caki-1 tumor cells after verapamil treatment. The uptake of adriamycin and maintenance of intracellular drugs were also significantly increased following verapamil treatment in RCC8701 tumor cells. These effects were sustained for as long as 8 hours after verapamil withdrawal. The cytotoxicity of adriamycin and epirubicin on RCC8701 and its MDR subline tumor cells was markedly intensified by verapamil. The verapamil modulation of cytotoxicity was in an immediate-reaction pattern and was dose-dependent, with synergistic effects. Long-term treatment was more effective than short-term treatment in RCC MDR sublines. The cytotoxicity of vinca alkaloid (vinblastine) and alkylators (carboplatin) was also enhanced by verapamil.

CONCLUSIONS

These results suggest that verapamil plays an important role in the circumvention of native and acquired chemoresistance of RRC because it suppresses membranous gp-170 expression and cytoplasmic drug transportation.

Establishment and characterization of renal cell carcinoma cell lines with multidrug resistance

Many of the discoveries of multidrug resistance (MDR) have resulted from studies using drug-resistant cultured tumor cell lines as experimental models. To date, there has been no report on the detailed characterization of such a cell line from renal cell carcinoma (RCC). By long-term exposure of an established RCC (RCC8701) to increasing concentrations of adriamycin, we established a series of subcultures that were considerably more resistant to the cytotoxic effect of this drug. Biological morphology and cell cycles were analyzed by morphometry and flow cytometry. The chemoresistance index of cells were measured by methyl tetrazolium assay. For evaluation of the expression of MDR-related protein (MRP), mdr-1, glutathione transferase (GST-pi), and topoisomerase II mRNAs, the reverse transcription-polymerase chain reaction was used. Membranous expression of mdr-1-related p-glycoprotein was analyzed by immunofluorescence cytometry. The intracellular content of both glutathione (GSH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were measured using a capillary electrophoresis method. Compared with parent cells, the resistant sublines had a slower growth rate and lower confluent density. They were smaller and mixed with giant cells in different sizes and with different numbers of nucleoli. Flow cytometric analyses showed that resistant cells had a greater percentage of cells in the G2/M phase. The resistant cells, RCC8701/ADR800, were 122 times more resistant to adriamycin and 238 times more resistant to epirubicin than the parent cells. The resistant cells also demonstrated cross-resistance to cisplatin and 5-fluorouracil. In addition to MRP, the contents of mRNA coding for mdr-1, GST-pi, and topoisomerase II in the MDR sublines were higher than in the native cell line. A higher content of cytoplasmic GSH and G-6-PDH were found in the resistant cells; however, the expression of the MDR-related membranous glycoprotein, p-glycoprotein, was not raised. The adriamycin-induced MDR sublines may be used as an experimental system for the search of a means to overcome drug resistance and elucidate possible mechanisms of acquired MDR involved in human renal cancer.

Halo Profiles and the Nonlinear Two- and Three-Point Correlation Functions of Cosmological Mass Density

We investigate the nonlinear two- and three-point correlation functions of the cosmological density field in Fourier space and test the popular hierarchical clustering model that assumes a scale-independent three-point amplitude Q. In high-resolution N-body simulations of both the n=-2 scale-free model and the cold dark matter model, we find that Q at late times is not constant but increases with wavenumber far into the nonlinear regime. Self-similar scaling also does not hold as rigorously for the three-point function as for the two-point function in the n=-2 simulation; this is perhaps a manifestation of the finite simulation volume. We suggest that a better understanding of the behavior of the two- and three-point correlation functions in the nonlinear regime lies in the link to the density profiles of dark matter halos. We demonstrate and quantify how the slopes of the correlation functions are affected by the slope of the halo profiles using simple halo shapes and analytic clustering models.

Flow-cytometric measurement of cellular changes in urine: a simple and rapid method for perioperatively monitoring patients after kidney transplantation

OBJECTIVE

In renal transplant patients having graft dysfunction, it is usually difficult to obtain the accurate diagnosis, such as acute rejection, acute tubular necrosis, infection, or cyclosporin nephrotoxicity. An accurate diagnosis can provide the proper treatment of these patients, thereby lessening the chance of kidney loss.

METHODS

A total of 42 patients were enrolled. By using the flow-cytometric technique, the white cell populations of urine in these patients were analyzed and linked to their clinical course. All patients underwent sonography-guided biopsy of the transplanted kidney with a definitive diagnosis.

RESULTS

When 10% lymphocytes and 15% granulocytes in urine were set as the cutoff point of a normal ratio threshold, the flow-cytometric analysis presented the highest sensitivity and the highest negative predictive rate for acute tubular necrosis. However, a lower sensitivity and positive predictive rate was found in acute rejection cases.

CONCLUSIONS

Our results suggest that flow-cytometric analysis of the urinary cell population can be used as an adjunct in patient follow-up after kidney transplantation.

Effect of capsaicin on the micturition reflex in normal and chronic spinal cord-injured cats

The effect of capsaicin (10-80 mg/kg sc) on reflex activity of the urinary bladder was examined in anesthetized normal as well as anesthetized and awake chronic spinal cord-injured (SCI) cats. In normal cats, capsaicin elicited a transient increase in the frequency of isovolumetric bladder contractions and reduced the volume threshold for inducing micturition, but did not depress the amplitude of bladder contractions or the reflex firing on bladder nerves. In anesthetized SCI cats, capsaicin depressed reflex bladder activity and firing on bladder nerves. In awake SCI cats, capsaicin initially decreased the volume threshold for inducing micturition; however, after a delay of 3-6 h the volume threshold increased and intravesical voiding pressure decreased. This effect persisted for 4-12 days. It is concluded that capsaicin-sensitive C fiber bladder afferents are not involved in initiating reflex micturition in normal cats, but play an essential role in triggering automatic micturition in chronic SCI cats. The results are consistent with the clinical data indicating that C fiber bladder afferents contribute to bladder hyperactivity and incontinence in patients with neurogenic bladder dysfunction.

Cocktail modulator mixtures for overcoming multidrug resistance in renal cell carcinoma

OBJECTIVES

To determine the effect of various modulators on intracellular drug accumulation in renal cell carcinoma (RCC) tumor cells and the modulation of cytotoxicity of various chemotherapeutic drugs on the native RCC cell line and acquired intrinsic multidrug resistance (MDR) sublines because MDR is a major obstacle to effective chemotherapy of RCC.

METHODS

The cytotoxicity of adriamycin to RCC 8701 and its MDR subline was analyzed. Fourteen MDR modulators, including calcium antagonists, protein kinase C inhibitor, glutathione transferase inhibitor, protein/peptide synthesis inhibitors, respiratory chain inhibitors, uncoupling reagent, adenosine triphosphate synthesis inhibitor, and ionophores, were examined for their MDR-reverse activity using the microplate tetrazolium test.

RESULTS

The intracellular adriamycin concentration significantly increased and reached maximum 4 hours after simultaneous treatment with calcium antagonists, tamoxifen, and oligomycin. The result demonstrated that verapamil, quinidine, tamoxifen, and oligomycin had an additive effect on the cytotoxicity of adriamycin and vinblastine against RCC8701 and RCC8701/ADR800 tumor cells. RCC8701/ADR800 tumor cells were more sensitive to modulator enhancement than native cells. The enhancement was related to the dosage and treatment duration of the modulators. Further trials on simultaneous additions to cocktail mixtures of the above four modulators showed no additive or synergistic effect on cytotoxicity against RCC8701/ADR800 tumor cells.

CONCLUSIONS

Calcium antagonists and tamoxifen and oligomycin can individually be an effective chemotherapy adjunct for overcoming the native drug resistance or acquired MDR in RCC. Combination regimens, however, need more study regarding timing of administration, dosage, and frequency of modulators.

The expression of mdr-1-related gp-170 and its correlation with anthracycline resistance in renal cell carcinoma cell lines and multidrug-resistant sublines

OBJECTIVES

To clarify the role of the membranous glycoprotein gp-170 in renal cell carcinoma (RCC) cell lines and their multidrug resistant (MDR) sublines. and to correlate gp-170 with the natural and acquired drug resistance of these cell lines to anthracyclines.

MATERIALS AND METHODS

The expression of gp-170 in five cultured RCC cell lines and serial RCC8701 MDR sublines was analysed by immunofluorescent flow cytometry. The chemosensitivity of these tumour cells to the anthracycline anticancer drugs adriamycin and epirubicin was measured using the microplate tetrazolium (MTT) cytotoxicity assay, and the results correlated with gp-170 expression.

RESULTS

All six natural RCC cell lines showed a variably increased expression of gp-170, with the A704 and Caki-1 cell lines the highest. In contrast, gp-170 expression increased and then was suppressed in acquired MDR sublines of RCC8701 cultured in increasing concentrations of adriamycin. The A704 and Caki-1 cells were much more resistant to adriamycin and epirubicin than the A498, ACHN and RCC8701 cell lines, in parallel with the expression of gp-170. The resistant cell line cultured long-term in 800 ng/mL adriamycin, RCC8701/ADR800, was 122 times more resistant to adriamycin and 238 times more resistant to epirubicin than the parent cell line: the pattern differed from that in native RCC cell lines and was unrelated to the expression of gp-170.

CONCLUSION

Membranous gp-170 plays an important role in MDR of native RCC cell lines, while acquired MDR cells have different mechanisms of obtaining drug resistance in addition to gp-170. This phenomenon may be applicable to the clinical treatment of patients newly diagnosed with RCC or those with disease refractory to chemotherapy.

Pathogenesis of ischemia reperfusion injury of the kidney after transient renal arterial clamping in rats

Renal function can be severely impaired through injuries sustained after both short and prolonged periods of complete ischemia. The magnitude of renal dysfunction resulting from these conditions and their reversibility depend on the duration of anoxia. In this study, we used a Sprague-Dawley rat model (5 to 7 rats in each group) to study the pathogenesis of short-term ischemia (30, 60, and 120 min)/reperfusion (2, 4, 24 h, 1 wk, and 3 wk) injury of the kidney under warm (room temperature) or cold (4 degrees C) conditions. Ischemia was induced by clamping the renal artery. Changes in kidney weight, histopathology, concentrations of serum thromboxane and leukotriene, and tissue malonyldialdehyde (MDA) concentration, numbers of apoptotic bodies, and p53 expression in the kidney were compared with those of sham-operated rats. The results showed that the immediate increase in kidney weight due to inflammatory swelling was associated with simultaneous elevation of serum thromboxane and leukotriene levels. The changes in mediator levels were closely related to the duration of ischemia and temperature. Histologic structures were preserved better when renal artery clamping was done at 4 degrees C. MDA peroxidation products from the ischemic tissue prominently increased 1 week following ischemia; this paralleled a secondary increase in leukotriene levels. Flow cytometric detection of p53 oncoprotein showed a marked increase at 1 week following ischemia, which was accompanied by the development of apoptotic bodies in ischemic tissues. These changes were also closely related to the ischemic time and temperature during ischemia. This animal model may be useful for future studies of the prevention of ischemia/reperfusion injury of the kidney and for selection of effective antioxidants.

Characterization and modulation of transitional cell carcinoma cell lines with acquired multidrug resistance

OBJECTIVES

To characterize in vitro drug-induced multidrug resistance (MDR) in transitional cell carcinoma (TCC) cell lines, and to elucidate the possible mechanisms of acquired MDR and their modulation.

MATERIALS AND METHODS

Two drug-resistant cell lines, TCC8702/A1000 (adriamycin 1000 ng/mL) and TCC8803/A200 (adriamycin 200 ng/mL), were established after long-term adriamycin treatment for at least 16 months. Their biological characteristics, including growth morphology, doubling time and cell cycle, were analysed. The drug-resistance pattern to various anticancer drugs was measured using a microplate cytotoxicity assay. The modulation of drug sensitivity by calcium-channel blockers and protein kinase C inhibitor was assessed among the different cancer cell lines.

RESULTS

Both MDR sublines had lower growth rates, lower saturation densities and higher nuclear/cytoplasmic ratios than the parent cell lines. DNA staining and cell cycle analysis revealed that both TCC8702/A1000 and TCC8803/A200 cells had a decreased S-phase fraction and the TCC8803/A200 cells a changed stem line; both sublines showed increased expression of membranous glycoprotein gp-170. The cytoplasmic content of glutathione and glucose-6-phosphate dehydrogenase were not related to the MDR development in the sublines. The drug-resistance index of TCC8702/A1000 to adriamycin was 121-fold higher than the native cell line and TCC8803/A200 was 189-fold higher. TCC8803/A200 also had a broader MDR to cisplatin, vinblastine and vincristine. Calcium-channel blockers (verapamil, quinidine) and protein kinase C inhibitors (tamoxifen) inhibited gp-170 activity and slowed the drug-efflux pump, with the acquired-MDR cells subsequently accumulating anticancer drugs. A calcium antagonist-based combination of modulators all presented synergistic cytotoxic enhancement of the anticancer drugs. Parent TCC cell lines had a poorer response to modulator treatment than their MDR sublines.

CONCLUSION

Different MDR mechanisms and subsequent modulator responses exist between native and acquired drug resistance in TCC cells. Acquired MDR seems strongly related to increased gp-170 expression and responds well to calcium antagonists. This phenomenon may be applicable in clinical conditions.

Monoclonal antibodies against renal tumors: the potential application in discrimination of ambiguous adenocarcinoma or transitional cell carcinoma of kidney

PURPOSE

We tested the discrimination ability of 2 monoclonal antibodies, mAB 90 and 2-2, in renal carcinomas, including renal cell carcinoma and transitional cell carcinoma of the kidney.

MATERIALS AND METHODS

Two monoclonal antibodies raised in renal adenocarcinoma (mAB 90, IgG3 subclass and mAB 2-2, IgG1 subclass), have been generated in our laboratory by hybridoma technique. The tumor associated antigens recognized by these IgG subclass monoclonal antibodies are located in the cell membrane of tumor cells. Antibodies were purified from mice ascites through protein A-Sepharose 4B affinity column and then conjugated with fluorescein isothiocyanate fluorescence by dimethyl sulfoxide method. The binding activity of these antibodies was measured by direct immunofluorescence method and analyzed in a flow cytometer. Forty-five cases of renal cell carcinoma and 16 cases of transitional cell carcinoma of the renal pelvis were collected, and the recognition power of these 2 antibodies was tested. Frozen tumor tissues were prepared and allocated into single cell suspensions in phosphate buffered saline before adding diluted (1:10) conjugated antibodies. Irrelevant antibody and negative tumor cell lines without any reaction with these antibodies were used as background fluorescence control.

RESULTS

Reactivities of mAB 90 and mAB 2-2 for renal cell carcinoma tissues were 80 and 91%, respectively. On the contrary the reactivities of mAB 90 and mAB 2-2 for transitional cell carcinoma of renal pelvis tissues were 0 and 69%, respectively. mAB 90 (+)/mAB 2-2 (-) expression pattern had 76% accurate diagnostic rate for renal cell carcinoma and mAB 90 (+)/mAB 2-2 (+) pattern had 69% accurate diagnostic rate for transitional cell carcinoma of the kidney.

CONCLUSIONS

When facing pathologically ambiguous kidney tumors, the binding specificity of mAB 90 and mAB 2-2 may be useful for discrimination between renal cell carcinoma tumors and transitional cell carcinoma of the renal pelvis.

The correlation of membranous glycoprotein-gp-170, cytoplasmic glutathione and glucose-6-phosphate dehydrogenase levels with multidrug resistance in transitional cell carcinoma cell lines of the urinary tract

The expression of membranous glycoprotein gp-170, cytoplasmic glutathione (GSH) and energy-related glucose-6-phosphate dehydrogenase (G-6-PD) in cultured normal urothelial cells and transitional cell carcinoma (TCC) cell lines was analyzed by flow cytometric and enzymatic methods. The chemosensitivity of these tumor cells to four major types of anticancer drugs, including cisplatin, thiotepa, methotrexate, 5-fluorouracil, adriamycin and vinblastine, was correlated with biological activities in TCC cell lines. The TCC cell lines displayed a general sensitivity to anticancer drugs with a low incidence of highly resistant cell lines (23%). The expression of multidrug resistance was not related to cellular differentiation or invasiveness of cancer cells. Only 24% of TCC cell lines had an elevated expression of gp-170, but their expression was not related to drug resistance. Increased cytoplasmic GSH and G-6-PD was observed in over 90 per cent of TCC cell lines, but no correlation with drug resistance and cellular differentiation was observed. The biological activities of GSH and G-6-PD were not related to the drug resistance of TCC. The low expression rate of gp-170 in TCC cells indicates that other mechanisms should be involved in the development of MDR in TCC cells.

Epidermoid cysts of the testis: diagnosis by ultrasonography and magnetic resonance imaging resulting in organ-preserving surgery

OBJECTIVE

To present experience in the diagnosis and management of patients with an epidermoid cyst of the testes and to confirm the role of conservative surgery.

PATIENTS AND METHODS

The records from the last 26.5 years of patients diagnosed as having a testicular tumour were reviewed retrospectively. Those patients with a confirmed epidermoid cyst were evaluated for age, clinical assessment, methods of diagnosis, treatment and follow-up.

RESULTS

Amongst a total of 131 testicular tumours, 11 patients (8.4%; mean age 25.7 years, range 21-35) were diagnosed pathologically as having an epidermoid cyst. Pre-operative suspicion of the benign nature of the lesions was supported by testicular ultrasonography in six patients and supplemented with magnetic resonance imaging (MRI) in one. An operation sparing the testicles was performed in eight patients after the diagnosis of epidermoid cyst was confirmed from frozen sections. Three patients were treated by radical orchidectomy. There were no relapses after a median follow-up of 47.3 months (range 2-82).

CONCLUSION

In this series, the relative incidence of epidermoid cyst was higher than that reported in the literature (1-2%). Ultrasonography and MRI of the testes may allow the diagnosis to be made preoperatively. The absence of relapse in these patients further supports the use of organ-sparing surgery in these young men.

The guanylyl cyclase-A receptor transduces an atrial natriuretic peptide/ATP activation signal in the absence of other proteins

Attempts to activate partially purified preparations of the guanylyl cyclase-A (GC-A) receptor with atrial natriuretic peptide (ANP) have previously failed, leading to speculation that essential cofactors are lost during purification procedures. The receptor was modified to contain the FLAG epitope (DYKDDDDK), expressed in Sf9 cells, and purified to apparent homogeneity (4.3 mumol cyclic GMP formed/min/mg protein; 5.8 mmol 125I-ANP binding site/mg protein) by a combination of immunoaffinity, Q-Sepharose FF, and wheat germ agglutinin batch chromatography. High initial protein/detergent ratios, the presence of glycerol (40%), and the inclusion of protein phosphatase inhibitors in all buffers resulted in the purification of a receptor that continued to transduce the ANP/ATP activation signal. Both native and purified GC-A contained a single class of high affinity ANP binding sites (Kd = 60 pM) and an equivalent EC50 for ATP (0.3 mM). Positive cooperativity as a function of MnGTP was retained during purification. Thus, GC-A is capable of transducing a ligand binding signal in the absence of other proteins.

Snail-headed catheter retriever: a simple way to remove catheters from female patients

A snail-headed catheter retriever was designed to remove the Double-J* catheter from female patients. The catheter can be removed within a few minutes using topical anesthesia at the outpatient department without endoscopic instrumentation and lithotomy position. No infection or bleeding developed following the procedure and all patients tolerated it well. The cost-effective retriever can be used as a convenient alternative for Double-J catheter removal from female patients.

The expression of ferritin on renal cancers and its relationship with cellular differentiation and tumour stage

OBJECTIVES

To investigate ferritin expression in renal carcinoma and the correlation of expression with tumour differentiation and stage.

PATIENTS AND METHODS

Ferritin was immunohistologically detected in 35 patients (23 men and 12 women; mean age 58.2 years, range 40-82) with renal carcinoma and the findings compared with cellular type, tumour stage and the ferritin expression of a similar control population of 16 patients.

RESULTS

The incidence of ferritin expression in renal carcinomas was 51%. Expression was significantly related to tumour stage and not cellular type.

CONCLUSION

The results of this study re-emphasize the high expression of ferritin in renal cell carcinoma and the correlation of expression with tumour behaviour.

Effect of capsaicin on micturition and associated reflexes in chronic spinal rats

The role of capsaicin-sensitive bladder afferents in micturition was studied in unanesthetized chronic spinal rats. Reflex voiding in response to tactile stimulation of the perigenital region appeared 5-9 days after spinal cord injury (SCI) whereas voiding induced by bladder distension occurred 2-3 weeks after SCI. The frequency and amplitude of reflex bladder contractions recorded under isovolumetric conditions were similar in chronic spinal and urethane-anesthetized CNS-intact rats. However, cystometrograms (CMGs) performed 6-8 weeks after SCI revealed that the chronic spinal rats had larger bladder capacities (1.86 ml) than CNS-intact rats (0.48 ml) and also exhibited multiple, small-amplitude, nonvoiding bladder contractions that were not detected in CNS-intact rats. Administration of capsaicin (50 mg/kg s.c.) acutely (onset 14-40 min) suppressed reflex bladder activity induced by bladder distension or by perigenital stimulation in chronic spinal animals. However, pretreatment of chronic spinal rats with capsaicin (125 mg/kg s.c.) 4 days before the experiment did not depress voiding reflexes or change bladder capacity but did eliminate the nonvoiding contractions. Inhibition of reflex bladder contractions by mechanical stimulation of rectoanal canal or the uterine cervix-vagina was not altered by pretreatment with capsaicin. These data indicate that capsaicin-sensitive bladder afferents are not essential for the initiation of reflex micturition in chronic spinal rats. However, these afferents do contribute to hyperactivity of the bladder during the filling phase of the CMG. Thus, capsaicin-sensitive bladder afferents should be evaluated as possible targets for the pharmacological treatment of bladder hyperreflexia in patients with SCI.

Flow cytometric DNA and cytomorphometric analysis in renal cell carcinoma: its correlation with histopathology and prognosis

Cell material from 49 cases of archival paraffin-embedded tumor specimens of newly diagnosed renal cell carcinoma (RCC) was studied retrospectively using rapid flow cytofluorometric (propidium iodide) DNA analysis. The degree of ploidy (DNA index), percentage of cells in the S-phase (SPF), and modal nuclear size were determined from histograms. The tumors were classified as diploid (DNA index = 0.9-1.1) or aneuploid. Proliferative activities of the tumors were assessed from the proportion of S-phase cells. The aneuploid occurrence was 77.6% in our series. Univariate and multivariate logistic regression analyses of DNA ploidy and associated parameters showed that DNA ploidy was correlated with SPF of cells (P = 0.0061) as no correlation was seen between DNA ploidy, sex, age, histological type, tumor size, stage, and nuclear size (P = 0.0697). Multiple aneuploid stem lines had no influences on ploidy and prognosis. Comparison of survival data using the multivariate stepwise hazard rate and Lee-Desu statistics showed that patient prognosis was closely related to tumor size (P = 0.006) and staging (P < 0.0001). DNA ploidy had marginal correlation to progression and disease-specific death (P = 0.064). Nevertheless, flow cytometric analysis in conjunction with conventional histopathology may have a potential role for the management of patients with RCC.

PA28, an activator of the 20 S proteasome, is inactivated by proteolytic modification at its carboxyl terminus

PA28, a protein activator of the 20 S proteasome, was previously identified in soluble extracts of bovine red blood cells (Ma, C.-P., Slaughter, C. A., and DeMartino, G. N. (1992) J. Biol. Chem. 267, 10515-10523). To determine whether this regulatory protein is as widely distributed as the proteasome, PA28 content and activity were examined in various eukaryotic tissues by immunoblot analysis and by functional assays of tissue extracts. PA28 protein was present in all sources examined. PA28 activity, however, was not detected in many of these sources, including those with the highest level of PA28 protein. To determine the biochemical basis of this result, PA28 was purified from extracts of rat liver, which had high levels of PA28 protein but no PA28 activity. The resulting purified PA28 had no detectable activity but had native and subunit molecular weights indistinguishable from the active PA28 of bovine red blood cells. Using the inactivation of purified PA28 as an assay, a protein that inactivated PA28 without altering its apparent molecular weight on SDS-polyacrylamide gel electrophoresis was identified, purified, and characterized from bovine liver. It had biochemical and catalytic characteristics similar to those of lysosomal carboxypeptidase B. When leupeptin, an inhibitor of lysosomal carboxypeptidase B, was included in the buffers used for the preparation of PA28, PA28 activity was detected in tissues which otherwise failed to demonstrate this activity. A similar result was obtained when extracts were prepared in a manner that minimized disruption of lysosomes. Other carboxypeptidases such as carboxypeptidase Y and pancreatic carboxypeptidase B also inactivated PA28 without altering its apparent molecular weight. Active PA28 binds to the proteasome to form a protease-activator complex that can be isolated after velocity sedimentation centrifugation through glycerol density gradients. Carboxypeptidase-inactivated PA28 failed to form such a complex, suggesting that the carboxyl terminus of PA28 is required for binding to the proteasome. These results indicate the importance of the carboxyl terminus of PA28 for proteasome activation.

Effects of capsaicin on micturition and associated reflexes in rats

The effect of capsaicin on micturition and associated reflexes was studied in urethan-anesthetized female rats. Capsaicin or vehicle solution were administered 4 days before the experiment in a dose of 125 mg/kg sc or during the experiment in a dose of 50-100 mg/kg sc. Activity of the urinary bladder was recorded by measuring intravesical pressure via a urethral catheter while slowly filling (0.052 ml/min) the bladder or when the bladder was distended beyond the micturition threshold and maintained at a constant volume. Pretreatment with capsaicin did not significantly change various parameters of urinary bladder function including micturition volume threshold or the amplitude, duration, and interval between reflex bladder contractions. However, capsaicin pretreatment significantly reduced (80% decrease) the arterial pressor responses accompanying reflex bladder contractions and reduced by approximately one-half the percentage of animals in which bladder activity was inhibited by stimulation of the uterine cervix. A large dose of capsaicin (50 mg/kg sc) elicited an acute block of bladder activity that persisted for 8-15 h. This effect is attributable to an action on myelinated afferent or efferent components of the micturition reflex pathway. It is concluded that capsaicin-sensitive afferents are not essential for the performance of micturition in the rat. However, these afferents are involved in cervicovesical reflex mechanisms that modulate bladder activity and in vascular reflexes triggered by isometric bladder contractions.

The effect of methylene blue-sensitized photodynamic treatment on bladder cancer cells: a further study on flow cytometric basis

The cytotoxic effect mediated by methylene blue-sensitized photoinactivation on bladder cancer cells has been well known for years, but the actual mechanism is still not clear. Specific fluorescence stains were used in a multiparameter approach. The changes in cellular size, granularity, protein content, RNA and DNA were analyzed by flow cytometry. The results showed that, in addition to cell size, all the other parameters, including cellular granularity, protein, RNA and DNA, diminished following photodynamic therapy. The cytotoxic efficacy is closely related to time of stain and illumination. The DNA and cell cycle were affected simultaneously with decreased DNA content and arrest in the G0/G1 phase. These multistage processes occurred synchronously after the phototherapy. Our results suggest that the methylene blue-sensitized photooxidation of bladder cancer cells is carried out by multimedia reactions through which the intracellular proteins (enzymes in mitochondria), RNA (ribosomes) and DNA (chromatin) decrease with loss of cytoplasmic granularity.

Vicryl mesh for repair of severely injured kidneys: an experimental study

We evaluated the efficacy of wrapping the kidney with semi-elastic Vicryl mesh for control of hemorrhage and preservation of renal function following grade III kidney lacerations (shattered kidney) in dogs in which nephrectomy was indicated clinically. Wrapping of fragmented kidneys resulted in prompt, sustained hemostasis and reapposition of the renal parenchyma. At an average of 80 days after injury the renal lacerations were well healed. The Vicryl mesh had been fully reabsorbed and there was considerably less scar tissue at the site of parenchymal rupture and neither perirenal or intrarenal abscess nor hematoma was found, grossly or microscopically. Among 12 dogs with grade III kidney lacerations, the mean ratio of the effective renal plasma flow (ERPF) in the affected kidney to the ERPF in the uninjured contralateral kidney was 0.53 +/- 0.22. The mean ratio of creatinine clearance of the injured kidney to that of the uninjured contralateral kidney was 0.41 +/- 0.23. Changes in the serum renin levels were not statistically significant following injury. Our results seem to confirm that simple and rapid surgical treatment of severely shattered kidneys using semi-elastic Vicryl mesh is possible. The method may also be suitable for uncontrollable bleeding during nonextirpative kidney surgery.

Identification, purification, and characterization of a protein activator (PA28) of the 20 S proteasome (macropain)

A protein that greatly stimulates the multiple peptidase activities of the 20 S proteasome (also known as macropain, the multicatalytic protease complex, and 20 S protease) has been purified from bovine red blood cells and from bovine heart. The activator protein was a single polypeptide with an apparent molecular weight of 28,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and had a native molecular weight of approximately 180,000. This protein, which we have termed PA28, regulated all three of the putatively distinct peptidase activities displayed by each of two functionally different forms of the proteasome. This regulation usually included both an increase in the maximal reaction velocity and a decrease in the concentration of substrate required for half-maximal velocity and indicated that PA28 acted as a positive allosteric effector of the proteasome. PA28 failed, however, to stimulate the hydrolysis of large protein substrates such as casein and lysozyme. These results suggested that the hydrolysis of protein substrates occurred at a site or sites distinct from those that hydrolyzed small peptides and that the regulation of the two processes could be uncoupled. Evidence for direct binding of PA28 to the proteasome was obtained by glycerol density gradient centrifugation. PA28 may play an important regulatory role in intracellular proteolytic pathways mediated by the proteasome.

Cytomorphometric and flow cytometric analysis of bladder transitional cell carcinoma using acridine orange fluorochrome: correlation with histopathology and clinical behavior

Cell material from 79 cases of archival paraffin-embedded tumor specimens of newly diagnosed transitional cell carcinomas of the urinary bladder was studied retrospectively using rapid flow cytofluorometric DNA analysis. The male to female ratio was 62/17. The mean age at diagnosis was 65.3 +/- 10.8 years. Clinical characteristics, including survival, recurrence and progression were closely related to the histopathologic grading and tumor staging. The tumors were classified as diploid (DI = 0.9-1.1) or aneuploid. Total aneuploid occurrence was 46%. The aneuploid frequency for the various tumor grades was 25% for grade 1, 37% for grade 2 and 78% for grade 3. Stages Ta (O) and Tl (A) tumors differed from muscle-invasive tumors (T2-4) in that they had a lower frequency of aneuploid occurrence (34%, 41% vs 50%, 73%, and 75%). Multiple aneuploid stem cell lines had no influence on tumor grade or stage. The DNA ploidy was closely related to the five-year survival rate, the probability of tumor recurrence and progression. On the contrary, the modal nuclear size of the tumor cells had no correlation with histopathology or the clinical characteristics. Bladder tumors of an intermediate grade (grade 2) may be subdivided into two groups with different outcomes on the basis of flow cytometric characteristics. It is concluded that DNA flow cytometry can serve as an additional prognostic parameter for bladder cancer patients in addition to conventional histopathology.

Safety and immunoresponse study of intravesical instillation of Taipei-NIPM bacillus Calmette-Guérin

The intravesical instillation of bacillus Calmette-Guérin (BCG) has proved to be an effective modality for prophylaxis of recurrent superficial bladder cancer and treatment of carcinoma in situ. The domestic BCG, named Taipei-NIPM, which is produced by the National Institute of Preventive Medicine, has been used as an anti-TBC vaccine in Taiwan for decades. In this study, we have investigated the safety and immune response in animals after intravesical BCG treatment to test its feasibility in future clinical application. Weekly instillation of BCG (1 mg/ml, 5-8 x 10(7) CFU/mg) for 6 instillations could induce lymphocytic infiltration, submucosal fibrosis, and granulomatous reaction after 4 weeks with mild decrease of bladder weight and high incidence of hematopyuria (75%). No changes in appetite, body weight, and splenic weight were noticed in the chronically treated rats. A delayed hypersensitivity test through foot pad swelling measurement reached 80% positive rates at 2 weeks. Cystometric study revealed a mild decrease in bladder capacity (33.3%) at 2 weeks and of contractile pressure of the urinary bladder in rats receiving BCG instillations. In addition, increase in lymphocytic infiltration by natural killer (NK) cells against YAC-1 cells could be detected after BCG treatment and this was related to dosage of BCG. The urothelial damage by cauterization and the number of instillations could also enhance NK cell activity. Low toxicity and high safety of intravesical instillation of the domestic BCG are demonstrated by this pilot animal study. This information on local and systemic immune responses can provide a solid base for future efficacy of BCG immunotherapy in bladder cancer patients using this domestic strain BCG.

DNA ploidy, S-phase fraction and cytomorphometry in relation to survival of human penile cancer

The prognostic significance of DNA ploidy, DNA index, S-phase fraction (SPF) and median nuclear size was studied in 11 patients with squamous cell carcinoma of the penis. These patients have been followed for a minimum of 7 months after diagnosis. Nuclear DNA content was determined by flow cytometry from paraffin-embedded tissue. Patients with DNA diploid cancer (n = 7, 64%) had a better survival rate than patients with aneuploid cancer, and a small SPF was associated with a favorable outcome. A statistically significant relation between median nuclear size and survival could be demonstrated. Small modal nuclear size associated with poorer prognosis. There was a significant difference in survival between metastatic and nonmetastatic groups of tumors during the follow-up period. This study suggests that flow cytometric determination of nuclear DNA ploidy from paraffin-embedded samples in penile cancer does add an additional prognostic determinant in addition to the clinical staging of tumors.

Effects of high-energy shock waves on murine renal cell carcinoma

The effects of high-energy shock waves (HESW) on a murine renal cell carcinoma (RenCa) was investigated. In vitro exposure of tumor cells to HESW resulted in a dose-dependent reduction in cell viability as determined by trypan blue dye exclusion, plating efficiency, growth curve, and soft agar clonogenic assays. Activity of lactic dehydrogenase (LDH) was detected in the supernatant after the HESW treatment due to cellular destruction, and a dose-dependent increase in cytocidal effect was demonstrated. Ultrastructural changes with swelling and distorted cristae of mitochondria, vacuolation, ribosomal lysis, and chromatinolysis were observed in HESW-treated RenCa cells. Flow cytometric (FCM) study revealed that DNA content of RenCa cells diminished after 200 HESW treatment, and RNA content of tumor cells decreased markedly after 400 HESW treatments. Partial or complete inhibition of tumor growth was shown in both animal modalities of subcutaneous inoculation and intravenous injection with sequential lung metastases. This study stressed again that HESW may play a role in combinational protocol for the treatment of human renal cell carcinoma in certain circumstances.

A genetic study of human interferon-alpha-induced repair of DNA damage in hepatitis B patients

In vitro treatment with human interferon-alpha (HuIFN-alpha) of hepatitis B virus-infected peripheral lymphocytes from 17 hepatitis B patients induced a decrease in the frequency of sister-chromatid exchanges (SCE). There was a significant difference in mean SCE frequencies between the HuIFN-alpha-treated patients and the control group, but not between acute and chronic hepatitis B patients treated with HuIFN-alpha.

Flow cytometric analysis of DNA ploidy, cell cycle and cytomorphometry in sarcomatoid renal cell carcinoma

In 5 patients with sarcomatoid renal cell carcinoma, the nuclear DNA content and size were determined by flow cytometry (FCM), and the prognostic value of DNA ploidy, the percentage of S-phase cells (SPF), and the ratio of modal nuclear size with clinicopathologic behavior was analyzed. Age and clinical stage have been shown to have a strong correlation with prognosis. Older patients with a high stage of cancer had poor outcome with a shorter survival time. In all 60% of the tumors were aneuploid. Tumor invasiveness was related to DNA ploidy. With increasing stage, the overall incidence of aneuploid rises. One alive patient had diploid DNA while 75% of the patients who died of sarcomatoid renal cell carcinomas had aneuploid DNA. Diploid sarcomatoid renal cell carcinomas show significantly lower SPF than aneuploid tumors. There was no significant association between the modal nuclear size and the invasiveness of tumors or survival time. This study suggests that FCM analysis of tumor DNA content and cell cycle could be regarded as an additional prognostic determinant of sarcomatoid renal cell carcinoma.

Ultrastructural changes of bladder cancer cells following methylene blue-sensitized photodynamic treatment

The cytotoxic efficacy of methylene blue-sensitized photoinactivation of bladder cancer cells has been proved in vitro and in vivo in our previous work. The ultrastructural changes of MBT-2 murine bladder cancer cells following methylene blue-sensitized phototherapy have been evaluated by scanning and transmission electron microscopy. MBT-2 cells were pretreated with 0.1% methylene blue, and then exposed to ordinary light for different durations from 1 to 60 min. Both electron microscopic examinations showed that changes in tumor cells occurred at 5 min of illumination with fenestration and minipore formation on the cell membrane and mitochondrial disintegration. At 30 min, cleavage and cracking of the cell membrane with ribosomal lysis were noted. Finally, fragmentation with decomposition of the membrane and chromosomal condensation and lysis resulted at 60 min. This study showed that the cytotoxic effect induced by methylene blue phototherapy is initiated in the cell membrane and intracellular mitochondria in the early phase.

Histopathological effects and recovery rate of rat bladders following intravesical instillation of thiotepa, doxorubicin and mitomycin C

A study was made of the local reactions and systemic effects induced by intravesical instillations of thiotepa, doxorubicin and mitomycin C in rats. The control group received normal saline. In the 1-dose short-term experiments, rats treated with doxorubicin and mitomycin C had a high incidence of chemical reactions, including congestion of the mucosa with methylene blue stain, increased bladder weight with oedematous changes either in the mucosa (doxorubian) or the muscle layer (mitomycin C), and infiltration of polymorphonuclear cells 3 days after instillation. These local changes disappeared within 10 days. In long-term experiments with weekly instillations of chemotherapeutic drugs, the rats showed no significant change in weight, methylene blue staining or mucosal congestion. A high percentage of pyuria and microscopic haematuria with submucosal/muscular fibrosis was noted in rats receiving doxorubicin or mitomycin C. A severe dysplastic change in the urothelium was noted in rats treated with mitomycin C. These results suggest that careful follow-up is required in patients receiving intravesical doxorubicin or mitomycin C because of possible severe side effects in the bladder.

[Testicular morphological and biochemical changes after Fowler-Stephens orchiopexy in rats]

Fowler-Stephens orchiopexy is the most common method of treating high-positioned undescended testes. Its success rate has been reported to be as high as 50-70% based on palpation or in a few circumstances on biopsy. Although it is convenient to evaluate testicular function by palpation and/or biopsy, this method is very subjective and is not scientific enough. To determine testicular function more precisely and objectively, we performed the Fowler-Stephens orchiopexy on Sprague-Dawley rats and observed the morphological and biochemical changes, including assays of LDH, SDH and the testosterone level. In our morphological study, with the use of Fowler-Stephens orchiopexy, only 17% (3/18) of the rat tests could be salvaged. The others revealed either necrosis or fibrosis. Testicular LDH, checked at the 4th postoperative week, revealed 0.62 +/- 0.04 U/mg which was statistically different (p less than 0.05) from that of the control group and the hemicastrated group (0.77 +/- 0.05 U/mg and 0.76 +/- 0.07 U/mg, respectively). The SDH obtained from the testes also revealed significant differences between the study group and the control and hemicastrated groups. Values obtained were 2.67 +/- 0.15 mU/mg, 3.77 +/- 0.4 mU/mg and 3.77 +/- 0.33 mU/mg, respectively (p less than 0.05). Using electrophoresis, 3 out of 18 rats had typical X bands, which is the classical picture of a normal mature testis. In contrast, the others showed faint X bands at the 2nd postoperative week, which subsequently faded thereafter. During testicular ischemia, the Leydig cells are more resistant than the Sertoli cells and the germinal cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Mechanisms underlying the recovery of urinary bladder function following spinal cord injury

Micturition in cats and rats with an intact neuraxis is dependent upon a spinobulbospinal reflex activated by A delta bladder afferents. This report describes changes in micturition reflexes 2 h to 14 weeks following spinal cord transection at the lower thoracic level. In acute spinal cats micturition reflexes were blocked, however, several weeks after transection, a long latency (180-200 ms) spinal reflex could be activated by C-fiber bladder afferents. This reflex was blocked by capsaicin in doses (20-30 mg/kg, s.c.) that did not affect micturition reflexes in intact cats. Micturition reflexes were unmasked in acute spinal and facilitated in chronic spinal cats by naloxone, an opioid antagonist. Spinal neurons and axons containing opioid peptides were more prominent below the level of transection in chronic spinal cats. VIP, a putative neurotransmitter in C-fiber bladder afferents, inhibited micturition reflexes when injected intrathecally (2-10 micrograms) in intact cats but facilitated micturition reflexes in spinal cats (doses 0.1-1 micrograms, i.t.). VIP-containing C-fiber afferent projections to lamina I of the sacral spinal cord expanded in spinal cats. Thus VIP afferents may have an important role in the recovery of bladder reflexes after spinal injury. Paraplegic animals also exhibit bladder-sphincter dyssynergia, which causes functional outlet obstruction. Studies in rats have revealed that outlet obstruction induced by partial urethral ligation facilitates spinal micturition reflex pathways and causes an expansion of HRP-labelled bladder afferent projections in the spinal cord. These findings raise the possibility that the alterations in central reflex connections in paraplegic animals may be induced in part by changes in peripheral afferent input secondary to outlet obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Photoinactivation of bladder tumor cells by methylene blue: study of a variety of tumor and normal cells

Human bladder cancer cell lines, J82, Yen-87, Shen-87 and Zoa-88, and murine bladder cancer cell lines, MBT-2 and M1660, were used as target cells for dye-sensitized photoinactivation study in using methylene blue. Normal fibroblast cells, FB-1 and FB8490, were used as control group. The cytoplasmic activity of lactic dehydrogenase, soft agar clonogenic assay, and in vivo tumor growth, survival rate and tumor taking rate with or without photoinactivation were monitored and compared between different cell lines. Efficacy of photoinactivation was time-related and more than 90 per cent of cytotoxicity could be obtained within 60 minutes of illumination. The plateau of cytotoxicity curve could be achieved after staining for 30 minutes by methylene blue under the same illumination time. Normal fibroblasts had the same features with cancer cells. Photoinactivation of tumor cells showed significant inhibition of tumor growth and tumor taking rate in experimental animals. Survival rate was also significantly prolonged in the animals with tumor cells receiving photoinactivation. These results suggest that methylene blue-sensitized photoinactivation may be useful as an adjuvant photochemotherapy for superficial bladder cancer.

Differential diagnosis of testicular mass by cytological examination of seminal fluid collected by ejaculation or prostatic massage

The cytological examination of the seminal fluid of 3 patients with painless testicular masses was performed using an ordinary conventional technique. Neoplastic cells appeared in the ejaculate or fluid from prostatic massage of all patients. The final pathologies were seminoma, choriocarcinoma and mixed teratocarcinoma. Malignant cells were no longer found in the seminal fluid after orchiectomy. This sample, noninvasive technique plus further flow cytometric study of cellular DNA contents is a great help in the preoperative differential diagnosis of testicular masses.

Retroperitoneal lymphangioma. A case report

Retroperitoneal cystic lymphangiomas are rare benign tumours. Ultrasonography, computed tomography, lymphography or fine-needle percutaneous aspiration may be used to make the diagnosis pre-operatively. Complete excision of the cyst without rupture is the preferred treatment. However, in complicated cases a conservative surgical approach is mandatory.