The mechanosensitive ion channel PIEZO1 promotes satellite cell function in muscle regeneration

Muscle satellite cells (MuSCs), myogenic stem cells in skeletal muscles, play an essential role in muscle regeneration. After skeletal muscle injury, quiescent MuSCs are activated to enter the cell cycle and proliferate, thereby initiating regeneration; however, the mechanisms that ensure successful MuSC division, including chromosome segregation, remain unclear. Here, we show that PIEZO1, a calcium ion (Ca²⁺)-permeable cation channel activated by membrane tension, mediates spontaneous Ca²⁺ influx to control the regenerative function of MuSCs. Our genetic engineering approach in mice revealed that PIEZO1 is functionally expressed in MuSCs and that Piezo1 deletion in these cells delays myofibre regeneration after injury. These results are, at least in part, due to a mitotic defect in MuSCs. Mechanistically, this phenotype is caused by impaired PIEZO1-Rho signalling during myogenesis. Thus, we provide the first concrete evidence that PIEZO1, a bona fide mechanosensitive ion channel, promotes proliferation and regenerative functions of MuSCs through precise control of cell division.

Apoptosis is involved in maintaining the character of the midbrain and the diencephalon roof plate after neural tube closure

Apoptosis, a major form of programmed cell death, is massively observed in neural plate border and subsequently in the roof plate (RP). While deficiency of apoptosis often results in brain malformations including exencephaly and hydrocephalus, the impact of apoptosis on RP formation and maintenance remains unclear. Here we described that mouse embryos deficient in Apaf1, a gene crucial for the intrinsic apoptotic pathway, in C57BL/6 genetic background exhibited narrow and discontinuous expression of RP marker genes in the midline of the midbrain and the diencephalon. Instead, cells positive for the neuroectodermal gene SOX1 ectopically accumulated in the midline. A lineage-tracing experiment suggests that these ectopic SOX1-positive cells began to accumulate in the midline of apoptosis-deficient embryos after E9.5. These embryos further displayed malformation of the subcommissural organ, which has been discussed in the etiology of hydrocephalus. Thus, the apoptosis machinery prevents ectopic emergence of SOX1-positive cells in the midbrain and the diencephalon RP, and helps in maintaining the character of the RP in the diencephalon and midbrain, thereby ensuring proper brain development.

Abstract 374: Gpr68 Senses Blood Flow and is Essential for Vascular Physiology

Mechanotransduction plays a crucial role in vascular biology. One example of this is local regulation of vascular resistance via flow-mediated vasodilation (FMD). Impairment of this process is a hallmark of endothelial dysfunction, and a precursor to a wide array of vascular diseases such as hypertension and atherosclerosis. And yet, the molecules responsible for sensing flow (shear stress) within endothelial cells remain largely unknown. We designed a 384-well screening system that applies shear stress on cultured cells. We identified a mechanosensitive cell line that exhibits shear stress-activated calcium transients, screened a focused RNAi library, and identified GPR68 as necessary and sufficient for shear stress responses. GPR68 is expressed in endothelial cells of small diameter (resistance) arteries. Importantly, Gpr68-deficient mice display markedly impaired acute FMD and chronic flow-mediated outward remodeling in mesenteric arterioles. Therefore, GPR68 is an essential flow sensor in arteriolar endothelium, and is a critical signaling component in cardiovascular pathophysiology.

Piezo2 senses airway stretch and mediates lung inflation-induced apnoea

Respiratory dysfunction is a notorious cause of perinatal mortality in infants and sleep apnoea in adults, but the mechanisms of respiratory control are not clearly understood. Mechanical signals transduced by airway-innervating sensory neurons control respiration; however, the physiological significance and molecular mechanisms of these signals remain obscured. Here we show that global and sensory neuron-specific ablation of the mechanically activated ion channel Piezo2 causes respiratory distress and death in newborn mice. Optogenetic activation of Piezo2⁺ vagal sensory neurons causes apnoea in adult mice. Moreover, induced ablation of Piezo2 in sensory neurons of adult mice causes decreased neuronal responses to lung inflation, an impaired Hering-Breuer mechanoreflex, and increased tidal volume under normal conditions. These phenotypes are reproduced in mice lacking Piezo2 in the nodose ganglion. Our data suggest that Piezo2 is an airway stretch sensor and that Piezo2-mediated mechanotransduction within various airway-innervating sensory neurons is critical for establishing efficient respiration at birth and maintaining normal breathing in adults.

Impact of laparoscopy for diagnosis and treatment in patients with disorders of sex development

OBJECTIVE

To review laparoscopy in patients with disorders of sex development (DSD) in order to clarify its usefulness in diagnosis, devising subsequent therapeutic strategies and managing patients with various conditions.

PATIENTS AND METHODS

Between April 1992 and December 2012, 29 laparoscopic surgeries were performed in 25 DSD patients. Among them, ten were diagnostic laparoscopy including gonadal biopsy, and 19 were therapeutic laparoscopy. Surgical procedures and complications were evaluated.

RESULTS

For diagnostic laparoscopy, laparoscopic gonadal biopsy was performed in three patients. Inspection, with or without open gonadal biopsy, was performed on four out of seven patients with 46XY DSD or mixed gonadal dysgenesis (MGD). Additional surgery was planned and performed based on diagnostic laparoscopic findings in six out of seven patients. In the three patients with ovotesticular DSD, the gonadal pathology was diagnosed as: testis/ovary in one, testis/ovotestis in one and ovary/ovotestis in one--this was from the laparoscopic inspection and/or gonadal biopsy. However, the final diagnoses were bilateral ovotestis in two patients and ovary/ovotestis in one patient. For therapeutic laparoscopy, surgical procedures were: gonadectomy in 17 patients (bilateral in 13, unilateral in three, partial in two); hysterectomy in two patients; orchiopexy in one; and sigmoid vaginoplasty in one patient (included multiple procedures). There were no severe perioperative complications. In the four patients with a history of diagnostic laparoscopy, no severe intra-abdominal adhesions that would disturb therapeutic laparoscopic surgery were observed.

CONCLUSION

While diagnostic laparoscopy was helpful in devising a therapeutic surgical strategy in most of the patients with DSD who were suspected as having complex gonadal status or Müllerian duct derivatives, attention must be paid to precisely diagnosing the gonadal status in ovotesticular DSD. On the other hand, therapeutic laparoscopic surgeries were valuable procedures in treating DSD patients, even with a history of previous diagnostic laparoscopy.

Long-term outcome of single institutional experience with conservative and surgical management for renal artery aneurysm

BACKGROUND

Spontaneous rupture risk of a renal artery aneurysm (RAA) is extremely low. Indications for surgical repair of RAA remain uncertain.

OBJECTIVE

Long-term outcomes of conservative therapy and surgical repair were evaluated.

PATIENTS

The study included 58 patients (17 males, 41 females) who were diagnosed with RAA during the last 21 years. Median age at the time of diagnosis was 62 (19-85) years, and the median follow-up 69 months (range 3-216).

METHODS

The patients were divided into two groups, conservative group (n = 30) who had been followed with blood pressure control, and treatment group (n = 29), who underwent an intervention.

RESULTS

Multiple efferent aneurysmal branches were observed in seven conservative and 16 treatment cases (P = .002). The median maximum diameter of the aneurysm was lower in the conservative than the treatment group (15 versus 25 mm, P = .005). Two conservative group cases showed increases in aneurysm size during follow-up. The hypertensive state showed essentially no change in either group during the follow-up. Renal function decreased with age similarly both in conservative and treatment groups.

CONCLUSIONS

Our conservative management criteria for RAA are justifiable and even too strict.

Successful kidney transplantation ameliorates arterial stiffness in end-stage renal disease patients

PURPOSE

Successful kidney transplantation (KTx) can ameliorate bodily damage caused by end-stage renal disease (ESRD). Arterial stiffness (AS) is one of the critical factors that shorten the survival of patients due to cardiovascular events. KTx may reduce AS as well; however, this has not been investigated well. We therefore conducted a retrospective study using noninvasive pulse wave velocity (PWV), which is a useful index of aortic damage.

PATIENTS AND METHODS

Fifty-eight consecutive kidney recipients (34 men, 24 women) were enrolled in this study. Mean age at transplantation was 40.5 ± 12.3 years and the dialysis period was 73.1 ± 95.8 months. The brachial-ankle PWV was measured preoperatively and 6 months postoperatively. First, we investigated the relationship between the PWV and the other parameters related to AS. Second, we studied the pre- to posttransplant change in PWV to evaluate the amelioration of AS after successful KTx.

RESULTS

PWV showed significant positive correlations with age, systolic blood pressure (BP), diastolic BP, and abdominal aortic calcification index. After successful KTx, PWV significantly decreased (P < .01). In addition, systolic and diastolic BP significantly decreased (P < .01 and P < .05, respectively).

CONCLUSION

Successful KTx ameliorates AS in ESRD patients. This might explain the improved cardiovascular prognosis of ESRD patients who undergo KTx.

Live imaging of apoptosis in a novel transgenic mouse highlights its role in neural tube closure

Imaging of caspase activation in living mouse embryos during development suggests that caspase-mediated cell removal facilitates neural tube closure in a temporally regulated manner.

Many cells die during development, tissue homeostasis, and disease. Dysregulation of apoptosis leads to cranial neural tube closure (NTC) defects like exencephaly, although the mechanism is unclear. Observing cells undergoing apoptosis in a living context could help elucidate their origin, behavior, and influence on surrounding tissues, but few tools are available for this purpose, especially in mammals. In this paper, we used insulator sequences to generate a transgenic mouse that stably expressed a genetically encoded fluorescence resonance energy transfer (FRET)–based fluorescent reporter for caspase activation and performed simultaneous time-lapse imaging of apoptosis and morphogenesis in living embryos. Live FRET imaging with a fast-scanning confocal microscope revealed that cells containing activated caspases showed typical and nontypical apoptotic behavior in a region-specific manner during NTC. Inhibiting caspase activation perturbed and delayed the smooth progression of cranial NTC, which might increase the risk of exencephaly. Our results suggest that caspase-mediated cell removal facilitates NTC completion within a limited developmental window.

Prognostic significance of CD45RO+ memory T cells in renal cell carcinoma

Background:

Memory T cells are well known to have a critical role for host defense in humans. However, their role in actual human cancer remains largely unknown. In this study, we tried to reveal the clinical importance of tumour-infiltrating CD45RO+ memory T cells in renal cell carcinoma (RCC).

Methods:

We analysed 105 patients with RCC, who received radical or partial nephrectomy. Those were 65 in TNM stage I, 7 in stage II, 15 in stage III, and 18 in stage IV, respectively. CD45RO expression was evaluated by immunohistochemistry. CD4 and CD8 expressions were also systematically assessed in the same manner.

Results:

Patients with higher TNM stage or high nuclear grade were found to have higher densities of CD45RO. Furthermore, CD45RO status was positively correlated with preoperative C-reactive protein level. In prognostic analysis, CD45RO+lo patients had a significantly better prognosis than CD45RO+hi patients. There was also a significant difference between CD4+lo and CD4+hi groups, whereas no significant difference was observed in CD8 T-cell status. Finally, multivariate analysis revealed that CD45RO+ status was the independent prognostic factor for patient overall survival.

Conclusion:

CD45RO+ memory T-cell status has a significant independent prognostic value, indicating that the adaptive immune response is functionally critical in human RCC.

Perioperative morbidity and mortality in patients treated by radical cystectomy: A multi-institutional retrospective study

270

Background: It is well known that radical cystectomy is associated with comparatively high perioperative morbidity and mortality. In the present study, we collected data of perioperative outcomes from Hokkaido University Graduate School of Medicine and our teaching hospitals and assessed the complications and death rate within 90 days after radical cystectomy.

Methods: We collected clinical data of 970 patients undergoing radical cystectomy for nonmetastatic bladder cancer in 21 institutions between 1999 and 2009. We then assessed 90-day complications and death after radical cystectomy. The complications were classified according to the modified Clavien classification. Over 40 variables were included in the analysis, including age, ASA score, BMI, comorbidity, neoadjuvant chemotherapy, clinical stage, type of urinary diversion, operative time, estimated blood loss, transfusion, and hospital stay. Statistical analysis was performed utilizing Student's t-tests, chi-square tests, and logistic regression analysis.

Results: The median patient age was 70 (range, 25-91) years old. 62.5% of patients had an ASA score≥2. Regarding the urinary diversion, ileal conduit was performed in 523 (53.6%) patients, neobladder in 178 (18.4%), ureterocutaneostomy in 255 (26.3%). Median operative time was 399 (range, 100-927) minutes. Median hospital stay was 39 (0-364) days. Regarding the complications, 660 (68%) patients experienced at least one complication and death rate within 90 days after surgery was 1.34% (n=13), respectively. Of the complications, 34.1% was classified as grade 1, 41.5% as grade 2, 20.1% as grade 3, 1.1% as grade 4, 1.2% as grade 5. Multivariate analysis identified age≥70 (odds ratio 1.41), urinary diversion utilizing intestine (OR 1.58) and operative time ≥ 400 (OR 1.54) were independent risk factors.

Conclusions: Death rate was 1.34%, which was compatible to reports form western high- volume centers. About two-thirds of the patients experienced at least one complication, although they were mostly classified as grade 2 or less. Age, urinary diversion, and operative time were significant risk factors for perioperative complications after radical cystectomy.

No significant financial relationships to disclose.

Predictors of long-term survival in patients with metastatic renal cell carcinoma in the cytokine era: An analysis of 473 patients treated between 1995 and 2005

335

Background: Based on the clinical data in Japanese renal cell carcinoma (RCC) patients who underwent cytokine therapy (Naito et al, Eur Urol 2010), the overall survival (OS) of these patients has been considered to be better than that of Caucasian patients. We identified long-term survivors among a cohort of 473 metastatic RCC patients, and explored clinical predictors of OS in these patients.

Methods: Between 1995 and 2005, 473 patients with metastatic RCC were the subjects of this retrospective analysis. Three hundred sixty-one (76%) patients received IFN-α and no patient did molecular-targeted drugs. The patients with survival times of greater than 5 years after the development of metastases were identified as long-term survivors. Multiple logistic regression analysis was performed to evaluate the impact of clinical variables potentially influencing OS.

Results: Median OS for all patients was 22.3 months (95%CI 18.7-27.6), the estimated 5-year survival rate was 27.4% (95% CI 22.9-31.9). Sixty-eight patients (14.4%) among 473 patients were identified as long-term survivors. Twenty-six (38%) had metastases at diagnosis of kidney cancer, 3 (4%) and 11 (16%) had liver mets and bone mets, respectively. According to MSKCC risk classification, 19 (28%), 28 (41%), and 6 (9%) were classified as favorable, intermediate, and poor risk, respectively. All patients had undergone prior nephrectomy, and 40 (59%) underwent metastatectomy. Multiple logistic regression analysis from all patients identified metastatectomy (HR 5.0; 95%CI 2.7-9.5) and MSKCC risk group (HR 3.7; 95%CI 1.5-9.1) as adverse prognostic factors for long-term OS.

Conclusions: Selected patients with metastatic RCC who can undergo metastatectomy have a good opportunity for long-term survival, especially those with favorable or intermediate risk classified by MSKCC risk classification.

No significant financial relationships to disclose.

Role of lymph node dissection in the treatment of urothelial carcinoma of the upper urinary tract: multi-institutional relapse analysis and immunohistochemical re-evaluation of negative lymph nodes

AIM

To determine the role of lymph node dissection (LND) in the treatment of urothelial carcinoma (UC) of the upper urinary tract (UUT).

PATIENTS AND METHODS

[Study-1] A retrospective multi-institutional study evaluated 293 patients undergoing predominantly nephroureterectomy for UC of the UUT. Of 293 patients, 267 patients had pure UC and 26 demonstrated other histological components. Regarding the pathological node status, 130 patients had pN0 disease, 141 patients had pNx disease and 22 patients had pN+ disease. The sites of initial recurrence and time to first recurrence were reviewed. The sites of recurrence were classified as locoregional or distant recurrence. The relationship between node status and future recurrence was analyzed. [Study-2] Fifty-one patients treated by nephroureterectomy at Hokkaido University Hospital were included. All had LND and all LNs were negative on hematoxylin and eosin staining. We re-evaluated the presence of micrometastasis in LND specimens by anti-cytokeratin immunohistochemistory.

RESULTS

[Study-1] Of 293 patients, 76 developed disease relapse. Regional lymph node recurrence was the most common site (34 patients). On multivariate analyses that adjusted for the effect of tumor stage and tumor grade, pNx (skipping LND) was an adverse factor not only for locoregional recurrence, but also for distant relapse. [Study-2] Immunohistochemistry identified micrometastases in 7 (14%) of 51 patients. Regarding survival, 5 of these 7 patients with micrometastases were alive at last follow-up.

CONCLUSIONS

On relapse analysis, skipping LND was an adverse factor not only for locoregional recurrence, but also for distant relapse. Immunohistochemistry detected micrometastases in about 14% of patients previously diagnosed as pN0. These findings further support a potential therapeutic benefit of LND by eliminating micrometastases.

Simultaneous expression of different transgenes in neurons and glia by combining in utero electroporation with the Tol2 transposon-mediated gene transfer system

In utero electroporation is widely used to study neuronal development and function by introducing plasmid DNA into neural progenitors during embryogenesis. This is an effective and convenient method of introducing plasmid DNA into neural precursors and is suitable for manipulating gene expression in cells of the CNS. However, the applicability of this technique is comparatively limited to neuronal research, as the plasmid DNA introduced into neural progenitors during embryogenesis is diluted by cell proliferation and is not stably maintained in glial cells generated around and after birth. To overcome this limitation, we applied the Tol2 transposon system, which integrates a transgene into the genome of the host cell, to in utero electroporation. With this system, we confirmed that the transgene was effectively maintained in the progeny of embryonic neural precursors, astrocytes and oligodendrocytes. Using the glial promoters GFAP and S100β, targeted and stable expressions of transgenes in glia were obtained, which enabled the expression of different transgenes simultaneously in neurons and glia. Glia-targeted expression of the transgene that causes neuronal migration defect was achieved without the defect. Thus, use of the Tol2 transposon system in combination with in utero electroporation is a powerful method for studying glia-neuron interactions in vivo.

Purified eicosapentaenoic acid induces prolonged survival of cardiac allografts and generates regulatory T cells

Fish oil, which is rich in eicosapentaenoic acid (EPA), has been found to have immunomodulatory effects. We examined whether administration of purified EPA affected survival of fully mismatched murine cardiac allografts. Hearts from C57BL/10 (H-2(b)) mice were transplanted into CBA (H-2(k)) recipients treated with one intraperitoneal dose of purified EPA the day of transplantation. Untreated CBA recipients and recipients given 0.1 g/kg of EPA rejected C57BL/10 hearts (median survival time [MST], 8 and 13 days, respectively). With a 1.0 g/kg dose of EPA, graft survival was markedly prolonged (MST >100 days). To determine whether regulatory cells were generated, naïve mice (secondary recipients) underwent adoptive transfer of splenocytes from EPA-treated primary recipients and cardiac allograft transplantation. Adoptive transfer of whole, CD4(+) and CD4(+)CD25(+) splenocytes from EPA-treated recipients induced indefinite survival in secondary recipients. Flow cytometry showed that the CD4(+)CD25(+) cells were Foxp3(+). In reverse transcriptase-polymerase chain reaction (RT-PCR) studies, the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) mRNA was upregulated by EPA treatment. A PPARgamma antagonist abrogated the prolongation of graft survival induced by EPA treatment (MST, 13 days). Thus, in our model, purified EPA induced prolonged survival of fully mismatched cardiac allografts and generated regulatory T cells dependent on PPARgamma activation.

Efficacy and thyroidal effects of sunitinib in Japanese patients with metastatic renal cell carcinoma: Hypothyroidism and thyroid atrophy as potential biomarkers for sunitinib?

e16097

Background: Although hypothyroidism is a well-known adverse effect of sunitinib in western patients (pts) with metastatic renal cell carcinoma (MRCC), the effects on thyroid gland of sunitinib in Japanese pts still remain unclear. We therefore evaluated thyroid dysfunction and thyroid atrophy in Japanese RCC pts who received sunitinib. Methods: Fourteen (8 males, 6 females) of 51 pts who were treated in a phase II trial of sunitinib in Japanese pts with MRCC were included in this retrospective study. All 14 pts were euthyroid at baseline. The measurement of serum thyroid function test (fT3, fT4, TSH) was performed at the beginning of each sunitinib treatment cycle. A TSH concentration greater than 10 mU/L was considered as hypothyroidism regardless of subclinical or clinical. CT volumetry of the thyroid gland was performed utilizing the data obtained for tumor assessment in a phase II trial. Tumor response was evaluated based on the RECIST criteria. Results: 9 (64%) of 14 pts achieved RECIST-defined objective response (1 CR, 8 PRs). With regard to thyroid function, hypothyroidism was experienced by 11 (79%) pts. Three of 11 pts had Sunitinib-induced thyrotoxicosis before experiencing hypothyroidism. The mean time to development of hypothyroidism was 55 days (range 13–668). Six pts received typical doses of L-thyroxine. The response rate was 73% (8/11) in pts with hypothyroidism and 33% (1/3) in pts without. With regard to the volume of thyroid gland in 13 pts, 8 pts had more than 50% reduction comparing the volume at the baseline. Median reduction rate in volume of 13 pts was 57% (range 0–95%). Hypothyroidism was experienced by all 8 pts with more than 50% reduction in volume and 2 of 5 (40%) without. Furthermore, the response rate was 88% (7/8) in former pts and 40% (2/5) in latter pts. Conclusions: In addition to high anti-tumor efficacy, hypothyroidism and thyroid atrophy were commonly observed in Japanese MRCC pts who received sunitinib. Although further study should be required, these abnormal findings in thyroid gland following treatment with sunitinib may be potential biomarkers for tumor response to sunitinib.

[Table: see text]

Combination therapy of meloxicam, a selective COX-2 inhibitor, and interferon alfa in metastatic renal cell carcinoma: A phase II study on efficacy and toxicity

5105

Background: Cyclooxygenase (COX)-2 plays a major role in the development of cancer through numerous mechanisms. We have previously confirmed that COX-2 is expressed in a renal cell carcinoma (RCC) and it has an important role in tumorigenesis and angiogenesis (Int J Cancer 2004). Some preclinical studies suggest that a selective COX-2 inhibitor may augment the antitumor effects of immunotherapeutic agents. We conducted a phase II trial of the combination of meloxicam, a selective COX-2 inhibitor, and interferon (IFN)-alfa 2a in metastatic RCC in order to test the hypothesis that meloxicam enhances the response to the immunotherapy. Methods: Eligible patients had metastatic RCC, no prior systemic therapy, performance status 0–2, measurable disease. Patients received IFN 3–5 MIU 3x/week and meloxicam 10 mg/daily orally. This was a single-stage trial. Primary end points were RECIST response rates and toxicity. Results: Twenty-one patients were enrolled. Patients characteristics included: median age 63 years (49–75), male/female: 16/5, PS 0/1/2: 11/6/4, prior nephrectomy: 16 (76%). MSKCC prognostic categories were good: intermediate: poor (24%: 48%: 29%). A median follow-up was 8 months (range 3–29+) and 18 of 21 (86%) patients are still alive. Toxicities were mostly grade 1 or 2 (fever, fatigue, anorexia, depression), except 1 patient with grade 3 liver dysfunction. Among 20 patients evaluable for response, complete response (CR) was observed in 3 patients (15%) and partial response (PR) in 5 (25%), yielding an overall response rate of 40% (95% CI: 17–63). An additional 5 patients (25%) had stable disease. Five of 6 patients classified as poor risk by MSKCC prognostic classification obtained a CR or PR, as did 3 of 14 patients as good or intermediate risk (p=0.038). Median time to progression for 20 patients was 6 months (1–29+). Conclusions: The overall response rate of 40% for the combination of meloxicam and IFN-alfa in metastatic RCC is greater than that of IFN-alfa alone reported previously, suggesting that meloxicam can enhance the response to immunotherapy. Further investigation with this combination is warranted.

No significant financial relationships to disclose.

Dependence of the photoelectrochemical performance of sensitised ZnO on the crystalline orientation in electrodeposited ZnO thin films

The influence of the crystal orientation in porous crystalline films of ZnO electrodeposited on the photoelectrochemical characteristics of the films is studied. For differently oriented ZnO thin films following removal of the respective structure-directing agent (SDA) and adsorption of a sensitiser, time-resolved photocurrent measurements, intensity modulated photocurrent spectroscopy (IMPS), intensity modulated photovoltage spectroscopy (IMVS) and current-voltage curves were measured in acetonitrile-based electrolytes containing I(3)(-)/I(-) as the redox electrolyte. The crystal orientation has a significant influence on the charge transport across such films and hence is reflected in the observed electrode kinetics. Films originally grown in the presence of, e.g., Coumarin 343 as a SDA, showed a significantly faster response to illumination. Increased electron diffusion coefficients and diffusion lengths were calculated from the results of IMPS and IMVS, caused by a faster electron movement in the films. Implications of these findings on further improvements of sensitised ZnO films prepared by electrochemical deposition are discussed.

NVP-TAE226, a potent dual FAK/IGF-IR kinase inhibitor, prevents breast cancer metastasis in vivo

13163

Background: Focal Adhesion Kinase (FAK) and Insulin-like Growth Factor-1 Receptor (IGF-IR) kinase are attractive anti-cancer drug targets because they are both drivers of tumor cell proliferation, migration, and survival. Although virtually every cell type expresses FAK, it is generally overexpressed in tumor cells. FAK levels are greatest in highly metastatic tumors. A selective FAK inhibitor would be expected to halt or kill invasive tumor cells, and potentially interfere with normal cell migration (e.g. endothelial cells). IGF-IR function is required for tumor cell survival, but dispensable for survival of normal cells. Therefore, a dual inhibitor of both kinases may selectively block the growth, migration, and survival of FAK- and IGF-IR- expressing tumor cells compared to proliferating and migrating normal cells. Methods: NVP-TAE226, a novel small molecule developed as an inhibitor of FAK, was evaluated in kinase enzymatic assays, cell-based kinase assays and 4T1 metastatic breast carcinoma in vivo model. Results: NVP-TAE226 inhibits FAK with low nanomolar IC50 values in a purified kinase enzymatic assay. In cell-based kinase assays, FAK and IGF-IR kinase were inhibited with an IC50 range of 100 to 300 nM compared to the other kinases tested which were >10-fold less sensitive. Oral administration of NVP-TAE226 inhibited 4T1 murine breast tumor growth and metastasis to the lung in a dose-dependent manner. The compound was well tolerated in mice as determined by measuring changes in body weight. The highest dose of 100 mg/kg, qd, 5x/week showed T/C value of 18%. Inhibition of FAK autophosphorylation at Y397 and Akt phosphorylation at Serine473 was observed in a dose-dependent manner in 4T1 breast carcinoma. Conclusions: NVP-TAE226 represents a novel class of selective and small molecule kinase inhibitors that have potential clinical applications with a potent in vivo activity.

[Table: see text]

Salvage chemotherapy with paclitaxel, ifosfamide, and nedaplatin in patients with urothelial cancer who had received prior cisplatin-based therapy

4579

Background: The combination chemotherapy of paclitaxel, ifosfamide, and nedaplatin (PIN regimen) has been shown to be effective in patients with advanced urothelial cancer. The aim of this presentation is to evaluate long-term followup outcomes in patients who had treated with standard cisplatin-based chemotherapy. Methods: The PIN regimen consisted of paclitaxel 175 mg/m2 on day 1, ifosfamide 4.5 g/m2 divided over days 1, 2 and 3, and nedaplatin 70 mg/m2 on day 1; PIN was given every 28 days. The doses of nedaplatin and ifosfamide were reduced according to the impairment of renal function (24h CCr) just before starting each cycle of PIN therapy Results: Thirty two patients who had previously undergone cisplatin-based chemotherapy were entered onto the study (median age, 66 years; median performance status, 1, median 24h CCr, 62ml/min [29–119ml/min] ). Metastatic sites at study entry included the lymph nodes (24), lung (6), bone (5), primary (5), soft tissue (3), and liver (2). Among the 32 assessable patients, there were 5 CRs (16%) and 19 PRs (59%) for an overall RR of 75 % (95% confidence interval [CI], 59–91 %). The median time to progression was 8 months (range, 0–50+ months) and the median survival was 22 months (range, 4–52+ months). Twelve patients received the full dose of PIN combination (median 5 cycles) and 20 patients required dose reduction (median 3 cycles). Nine of 12 (75%) patients who were treated with the full-dose PIN combination obtained a CR or PR, as did 15 of 20 (75%) patients who required dose reduction. Grades 3 and 4 neutropenia occurred in all patients. Febrile neutropenia occurred in 8 (25%) patients. Grades 3 and 4 thrombocytopenia occurred in 8 (25%) patients. Grades 3 and 4 anemia was observed in 6 (19%) patients. Grade 3 neuropathy occurred in 1 (3%) patient, who could not continue to receive additional cycles of PIN combination after 3 cycles. No patient experienced renal failure. There were no treatment-related deaths. Conclusions: The PIN combination was highly active and tolerable in patients who had previously treated with cisplatin-based chemotherapy, and might be suitable for those with mild to moderate renal insufficiency.

No significant financial relationships to disclose.

Maternal genetic polymorphisms in CYP1A1, GSTM1 and GSTT1 and the risk of hypospadias

Hypospadias is one of the most common congenital anomalies. Increased exposure to environmental factors (endocrine-disrupting chemicals and smoking) or maternal endogenous estrogen may cause hypospadias because male sexual differentiation is dependent on normal androgen homeostasis. Moreover, interactions between genetic factors and cigarette smoking and other chemicals have been suggested. It has been demonstrated that the CYP1A1 metabolizes not only environmental chemicals but also estrogens, and glutathione-S-transferases (GSTs) are detoxification enzymes that protect cells from toxicants by conjugation with glutathione. In this study, to investigate the association of CYP1A1 (MspI), GSTM1 and GSTT1 polymorphisms with hypospadias, a case-control study of 31 case mothers who had boys with hypospadias and 64 control mothers was performed in Japan. These polymorphisms were investigated by PCR-based methods using DNA from peripheral lymphocytes. We found that the heterozygous CYP1A1 and heterozygous and homozygous CYP1A1 were less frequent in the case mothers than in the control mothers [adjusted odds ratio (OR)=0.17, 95% confidence interval (CI)=0.04-0.74, OR = 0.28, 95% CI = 0.08-0.97, respectively]. We found no effect of maternal smoking on the hypospadias risks among the gene polymorphisms. The results suggest that mothers with the CYP1A1 MspI variant allele may have a decreased risk for hypospadias.

Effect of tacrolimus and cyclosporine on renal microcirculation and nitric oxide production

OBJECTIVES

Cyclosporine (CSA) and tacrolimus (TAC) frequently induce nephrotoxicity and similar pathologic changes. Acute CSA-induced nephrotoxicity has been reported to be mediated by activation of vasoconstrictors such as endothelin. The purpose of the present study was to investigate the acute effects of TAC and CSA on the renal microcirculation and upon a vasodilator such as nitric oxide (NO) production.

METHODS

Renal blood flow (RBF) in the microcirculation was measured by a Laser Doppler flow meter in uninephrectomised rats. RBF, mean arterial pressure (MAP), and renal vascular resistance (RVR) were measured in the following groups: (a) TAC (0.1 to 2.0 mg/kg/h, n = 3 approximately 6); CSA (20 and 50 mg/kg/h, n = 5); (b) L-NAME (10 mg/kg), an NO synthase inhibitor, 8 minutes prior to TAC (0.5 and 1.5 mg/kg/h, n = 5), or CSA (20 and 50 mg/kg/h, n = 5). Stable NO end-products, serum NO(2) and NO(3), were measured by the Griess method (n = 5).

RESULTS

None of the parameters were changed by TAC alone, whereas TAC with L-NAME significantly reduced RBF (-28 +/- 7%) and increased RVR (46 +/- 17%) in a dose-dependent manner. CSA alone significantly reduced RBF (-37 +/- 6%) and increased RVR (69 +/- 22%) without any changes in MAP. The effects of CSA were enhanced by L-NAME. Serum concentration of NO(2) + NO(3) was significantly reduced by both L-NAME alone and CSA (50 mg/kg) (P < .05), while there were no changes with TAC (1.5 mg/kg).

CONCLUSIONS

Blockade of NO production enhance the vasoconstrictive effect of CSA, and unmasked such an effect of TAC. These results suggest that the nephrotoxicity of CSA and TAC may involve the NO system.

Diminished penile expression of vascular endothelial growth factor and its receptors at the insulin-resistant stage of a type II diabetic rat model: a possible cause for erectile dysfunction in diabetes

Erectile dysfunction (ED) is commonly experienced in men with diabetes mellitus. Vascular endothelial growth factor (VEGF) has been extensively documented for its pathogenic significance in different complications of diabetes. We hypothesized that expressions of VEGF, its receptors and its signaling pathway Akt may be drastically altered in diabetic penile tIssues and their alterations may modulate penile expression of the molecules that are believed to play a role in diabetic ED. Otsuka Long-Evans Fatty (OLETF) rats, a type II (non-insulin-dependent) diabetes mellitus, were used at the insulin-resistant stage of type II diabetes (20 weeks of age). We determined protein and mRNA expressions of VEGF, its receptors, Akt, nitric oxide synthase isoforms, and apoptosis-related molecules in the penis using immunohistochemistry, Western blotting, in situ hybridization, and real-time quantitative PCR analyses. The penile sections were also submitted to the Tdt-mediated dUTP nick end labeling assay for apoptosis. OLETF rats showed marked reductions in penile expression of VEGF, its two receptors and Akt. In OLETF rat penises, endothelial and neuronal nitric oxide synthase isoforms were expressed less abundantly. Furthermore, while anti-apoptotic markers, Bcl-2 and phosphorylated Bad, were down-regulated, pro-apoptotic markers, active caspase-3 and Bax, were up-regulated, resulting in the appearance of apoptotic cells in the penile tIssues of OLETF rats. The VEGF signaling system would work less well in diabetic penile tIssues as a result of the reduced expression, leading to diminished endothelial production of nitric oxide and apoptosis-related erectile tIssue damage. We propose that the abnormalities of the VEGF signaling system in the penis may play a role in the pathophysiology of diabetic ED.