Regulation of PDE5 expression in normal prostate, benign prostatic hyperplasia, and adenocarcinoma

BACKGROUND

Type 5 phosphodiesterase (PDE5) expression in the normal and pathological prostate is controversial.

OBJECTIVES

This study aimed at identifying the cell type/s, if any, expressing PDE5 in human healthy or pathological prostate sections in order to further validate the rationale of PDE5 inhibitor (PDE5i) treatment of benign prostatic hyperplasia (BPH) and their safety in the treatment of erectile dysfunction following prostate cancer (PCa) surgery.

MATERIALS AND METHODS

By immunohistochemical analysis, we studied PDE5 expression in tissue microarrays containing sections obtained from healthy, BPH, and PCa samples.

RESULTS

Our results showed that PDE5 is barely expressed in the epithelial or stromal compartment of normal human prostates, but it is highly expressed in the stromal compartment of BPH sections. We also found that a low but significant number of PCa samples (22%) expressed PDE5 in the epithelial cancer cells but not in stromal cells and that such expression was not correlated with the tumor aggressiveness, according to their Gleason score.

DISCUSSION AND CONCLUSION

PDE5 overexpression in the stromal compartment of BPH samples supports the rationale of PDE5 as a target in lower urinary tract symptoms of BPH. PDE5 expression in a significant percentage of PCa samples but the lack of correlation with the Gleason score suggests that this enzyme is not correlated with tumor aggressiveness; however, a role of PDE5 in the minimal residual disease of PCa cannot be excluded.

Increasing the dose intensity of chemotherapy by more frequent administration or sequential scheduling: a patient-level meta-analysis of 37 298 women with early breast cancer in 26 randomised trials

BACKGROUND

Increasing the dose intensity of cytotoxic therapy by shortening the intervals between cycles, or by giving individual drugs sequentially at full dose rather than in lower-dose concurrent treatment schedules, might enhance efficacy.

METHODS

To clarify the relative benefits and risks of dose-intense and standard-schedule chemotherapy in early breast cancer, we did an individual patient-level meta-analysis of trials comparing 2-weekly versus standard 3-weekly schedules, and of trials comparing sequential versus concurrent administration of anthracycline and taxane chemotherapy. The primary outcomes were recurrence and breast cancer mortality. Standard intention-to-treat log-rank analyses, stratified by age, nodal status, and trial, yielded dose-intense versus standard-schedule first-event rate ratios (RRs).

FINDINGS

Individual patient data were provided for 26 of 33 relevant trials identified, comprising 37 298 (93%) of 40 070 women randomised. Most women were aged younger than 70 years and had node-positive disease. Total cytotoxic drug usage was broadly comparable in the two treatment arms; colony-stimulating factor was generally used in the more dose-intense arm. Combining data from all 26 trials, fewer breast cancer recurrences were seen with dose-intense than with standard-schedule chemotherapy (10-year recurrence risk 28·0% vs 31·4%; RR 0·86, 95% CI 0·82-0·89; p<0·0001). 10-year breast cancer mortality was similarly reduced (18·9% vs 21·3%; RR 0·87, 95% CI 0·83-0·92; p<0·0001), as was all-cause mortality (22·1% vs 24·8%; RR 0·87, 95% CI 0·83-0·91; p<0·0001). Death without recurrence was, if anything, lower with dose-intense than with standard-schedule chemotherapy (10-year risk 4·1% vs 4·6%; RR 0·88, 95% CI 0·78-0·99; p=0·034). Recurrence reductions were similar in the seven trials (n=10 004) that compared 2-weekly chemotherapy with the same chemotherapy given 3-weekly (10-year risk 24·0% vs 28·3%; RR 0·83, 95% CI 0·76-0·91; p<0·0001), in the six trials (n=11 028) of sequential versus concurrent anthracycline plus taxane chemotherapy (28·1% vs 31·3%; RR 0·87, 95% CI 0·80-0·94; p=0·0006), and in the six trials (n=6532) testing both shorter intervals and sequential administration (30·4% vs 35·0%; RR 0·82, 95% CI 0·74-0·90; p<0·0001). The proportional reductions in recurrence with dose-intense chemotherapy were similar and highly significant (p<0·0001) in oestrogen receptor (ER)-positive and ER-negative disease and did not differ significantly by other patient or tumour characteristics.

INTERPRETATION

Increasing the dose intensity of adjuvant chemotherapy by shortening the interval between treatment cycles, or by giving individual drugs sequentially rather than giving the same drugs concurrently, moderately reduces the 10-year risk of recurrence and death from breast cancer without increasing mortality from other causes.

FUNDING

Cancer Research UK, Medical Research Council.

Formestane as Treatment of Advanced Breast Cancer in Elderly Women

Aims and background

The number of elderly people is increasing, and the proportion of breast cancer in female cancer patients older than 65 years is 26%. In elderly patients, hormone therapy is widely accepted as the treatment of choice, because of its efficacy and good tolerability compared to chemotherapy. The aim of this study was to evaluate the endocrinologic and clinical activity of formestane (4-hydroxyandrostenedione), a selective aromatase inhibitor, in elderly patients with advanced breast cancer.

Methods

Thirty-five patients older than 65 years, selected from a larger group, were given formestane (250 mg or 500 mg i.m. fortnightly). Patients were evaluable for tumor response after 4 doses of formestane. Blood samples were collected to evaluate E2, FSH, LH, SHBG and DHEAS serum levels at baseline and after 2, 4, 8,12 and 24 weeks.

Results

Thirty patients had PS ≤ 1 (ECOG) and only 5 patients had PS = 2. Twenty-six patients were ER positive. Previous hormonal treatment for metastatic disease had been given to 17 patients; only 1 case had received chemotherapy. The overall response rate was 51% (95% C.I. 35–67%) and the median response duration was 9.5 months. Three complete responses were observed on viscera. The best responses were obtained on soft tissues (59%); on bone and viscera the response was respectively 45% and 47%. Local and systemic tolerability was highly satisfactory. Formestane induced prolonged suppression of E2 levels in all of the patients, and a significant reduction in SHBG levels was also observed from month 2 onward. A statistically significant ( P = 0.0001) rise in serum FSH was also observed during the therapy.

Conclusions

The study showed that formestane induced a long-lasting suppression of E2 levels and a satisfactory overall response. In our opinion, the drug is an effective and well-tolerated approach in the management of advanced breast cancer in elderly patients.

Sox2 is not required for melanomagenesis, melanoma growth and melanoma metastasis in vivo

Melanoma is a dangerous form of skin cancer derived from the malignant transformation of melanocytes. The transcription factor SOX2 is not expressed in melanocytes, however, it has been shown to be differentially expressed between benign nevi and malignant melanomas and to be essential for melanoma stem cell maintenance and expansion in vitro and in xenograft models. By using a mouse model in which BRaf^V600E mutation cooperates with Pten loss to induce the development of metastatic melanoma, we investigated if Sox2 is required during the process of melanomagenesis, melanoma growth and metastasis and in the acquisition of resistance to BRAF inhibitors (BRAFi) treatments. We found that deletion of Sox2 specifically in Pten null and BRafV600E-expressing melanocytes did not prevent tumor formation and did not modify the temporal kinetics of melanoma occurrence compared to Sox2 wt mice. In addition, tumor growth was similar between Sox2 wt and Sox2 deleted (del) melanomas. By querying publicly available databases, we did not find statistically significant differences in SOX2 expression levels between benign nevi and melanomas, and analysis on two melanoma patient cohorts confirmed that Sox2 levels did not significantly change between primary and metastatic melanomas. Melanoma cell lines derived from both Sox2 genotypes showed a similar sensitivity to vemurafenib treatment and the same ability to develop vemurafenib resistance in long-term cultures. Development of vemurafenib resistance was not dependent on SOX2 expression also in human melanoma cell lines in vitro. Our findings exclude an oncogenic function for Sox2 during melanoma development and do not support a role for this transcription factor in the acquisition of resistance to BRAFi treatments.

Activated c-Kit receptor in the heart promotes cardiac repair and regeneration after injury

The role of endogenous c-Kit receptor activation on cardiac cell homeostasis and repair remains largely unexplored. Transgenic mice carrying an activating point mutation (TgD814Y) in the kinase domain of the c-Kit gene were generated. c-Kit^TgD814Y receptor was expressed in the heart during embryonic development and postnatal life, in a similar timing and expression pattern to that of the endogenous gene, but not in the hematopoietic compartment allowing the study of a cardiac-specific phenotype. c-Kit^TgD814Y mutation produced a constitutive active c-Kit receptor in cardiac tissue and cells from transgenic mice as demonstrated by the increased phosphorylation of ERK1/2 and AKT, which are the main downstream molecular effectors of c-Kit receptor signaling. In adult transgenic hearts, cardiac morphology, size and total c-Kit⁺ cardiac cell number was not different compared with wt mice. However, when c-Kit^TgD814Y mice were subjected to transmural necrotic heart damage by cryoinjury (CI), all transgenic survived, compared with half of wt mice. In the sub-acute phase after CI, transgenic and wt mice showed similar heart damage. However, 9 days after CI, transgenic mice exhibited an increased number of c-Kit⁺CD31⁺ endothelial progenitor cells surrounding the necrotic area. At later follow-up, a consistent reduction of fibrotic area, increased capillary density and increased cardiomyocyte replenishment rate (as established by BrdU incorporation) were observed in transgenic compared with wt mice. Consistently, CD45⁻c-Kit⁺ cardiac stem cells isolated from transgenic c-Kit^TgD814Y mice showed an enhanced endothelial and cardiomyocyte differentiation potential compared with cells isolated from the wt. Constitutive activation of c-Kit receptor in mice is associated with an increased cardiac myogenic and vasculogenic reparative potential after injury, with a significant improvement of survival.

Abstract P6-04-13: The role of precision medicine in "real-life" management of breast cancer patients: A survey assessing the current use and attitudes towards tumor molecular sequencing in clinical practice

Background: Personalized medicine is a rising paradigm in cancer care. The identification of pathways involved in carcinogenesis along with the development of targeted therapies has revolutionized cancer treatment. There is increasing availability of technologies that can interrogate the genomic landscape of the tumor; however, it is still uncertain whether such platforms are used in clinical practice.

Methods: We conducted a 28-item survey to investigate the current use of tumor molecular sequencing in the management of breast cancer patients. A link to the online survey was communicated via various platforms such as the European Society for Medical Oncology (ESMO) and European School of Oncology (ESO) newsletter, and via a dedicated mailing by the Breast International Group (BIG) and other academic groups. Descriptive statistical analysis and Fisher's exact tests were applied to explore potential association between the demographic characteristics and responses.

Results: A total of 211 physicians from 35 countries participated to the study between the 9 March and 3 June 2015, with 92% fully completed questionnaires. The mean age of the participants was 45 years (range 27-77). The majority of responders were medical oncologists (88%), practicing in Europe (69%) and working in academic institutions (66%). 62% (130/211) of participants had never requested tumor molecular sequencing for breast cancer patients. Working in academic institutions and having more time allocated to research were associated with the use of tumor molecular sequencing (p = 0.007 and 0.009, respectively). For the 81 participants that used tumor molecular sequencing in the past (Table 1), there was a significant association between accessibility and frequency of use (p=0.02). 92% (181/211) of participants claimed that they would probably use tumor molecular sequencing more often if it was more accessible. Lack of funding and lack of access to the technology were the main reasons for poor endorsement. 89% of participants believe that tumor molecular sequencing will play a major role in the management of breast cancer patients in the future. Current weak evidence and poor access to matched targeted therapy are the main concerns against a wider use of these platforms in clinical practice.

Table 1. Summary of replies from the 81 participants that used tumor molecular sequencing for breast cancer patientsQuestionResponseN (%)In what percentage of your breast cancer patients has tumor molecular sequencing been performed at least once?≤5%55 (68%) &gt;5%26 (32%)How often do the results lead to enrollment in a clinical trial?≤10%53 (65%) &gt;10%28 (35%)How confident are you in interpreting tumor sequencing results?Not at all/A little17 (21%) Somewhat/Highly64 (79%)Do you consider molecular sequencing platforms accessible?Not at all/A little45 (55%) Somewhat/Highly36 (45%)

Conclusion: Our survey indicates that molecular sequencing platforms are sometimes used, albeit not widely in guiding management of breast cancer patients. Poor accessibility may contribute to the low frequency of use, but lack of evidence and poor access to matched targeted therapy are also major concerns.

Citation Format: Gingras I, Sonnenblick A, Dolci S, de Azambuja E, Paesmans M, Delaloge S, Piccart MJ, Sotiriou C, Michail I, Azim Jr HA. The role of precision medicine in "real-life" management of breast cancer patients: A survey assessing the current use and attitudes towards tumor molecular sequencing in clinical practice. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-04-13.

SOHLH1 and SOHLH2 directly down-regulate STIMULATED BY RETINOIC ACID 8 (STRA8) expression

As the name implies, Stimulated by Retinoic Acid 8 is an early retinoic acid (RA) responsive gene pivotal for the beginning of meiosis in female and male germ cells. Its expression is strictly time-dependent and cell-specific (pre-meiotic germ cells) and likely requires a complex mechanism of regulation. In this study, we demonstrate a direct negative control of SOHLH1 and SOHLH2, 2 germ cell specific bHLH transcription factors, on Stra8 expression. We observed a negative correlation between STRA8 and SOHLH1 expression in prepuberal differentiating mouse KIT(+) spermatogonia and found that SOHLH1 and SOHLH2 were able to directly and cooperatively repress STRA8 expression in cell lines in vitro through binding to its promoter. We also identified 2 canonical E-Box motives in the Stra8 promoter that mediated the negative regulation of SOHLH1 and SOHLH2 on these gene both in the cell lines and KIT(+) spermatogonia. We hypothesize that this novel negative activity of SOHLH1 and SOHLH2 in male cooperates with that of other transcription factors to coordinate spermatogonia differentiation and the RA-induced meiosis and in female ensures STRA8 down-regulation at mid-end stages of meiotic prophase I.

Adjuvant Lapatinib and Trastuzumab for Early Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: Results From the Randomized Phase III Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization Trial

BACKGROUND

Lapatinib (L) plus trastuzumab (T) improves outcomes for metastatic human epidermal growth factor 2-positive breast cancer and increases the pathologic complete response in the neoadjuvant setting, but their role as adjuvant therapy remains uncertain.

METHODS

In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial, patients with centrally confirmed human epidermal growth factor 2-positive early breast cancer were randomly assigned to 1 year of adjuvant therapy with T, L, their sequence (T→L), or their combination (L+T). The primary end point was disease-free survival (DFS), with 850 events required for 80% power to detect a hazard ratio (HR) of 0.8 for L+T versus T.

RESULTS

Between June 2007 and July 2011, 8,381 patients were enrolled. In 2011, due to futility to demonstrate noninferiority of L versus T, the L arm was closed, and patients free of disease were offered adjuvant T. A protocol modification required P ≤ .025 for the two remaining pairwise comparisons. At a protocol-specified analysis with a median follow-up of 4.5 years, a 16% reduction in the DFS hazard rate was observed with L+T compared with T (555 DFS events; HR, 0.84; 97.5% CI, 0.70 to 1.02; P = .048), and a 4% reduction was observed with T→L compared with T (HR, 0.96; 97.5% CI, 0.80 to 1.15; P = .61). L-treated patients experienced more diarrhea, cutaneous rash, and hepatic toxicity compared with T-treated patients. The incidence of cardiac toxicity was low in all treatment arms.

CONCLUSION

Adjuvant treatment that includes L did not significantly improve DFS compared with T alone and added toxicity. One year of adjuvant T remains standard of care.

Fgf9 inhibition of meiotic differentiation in spermatogonia is mediated by Erk-dependent activation of Nodal-Smad2/3 signaling and is antagonized by Kit Ligand

Both fibroblast growth factor 9 (Fgf9) and Kit Ligand (Kl) signal through tyrosine kinase receptors, yet they exert opposite effects on meiotic differentiation in postnatal spermatogonia, Fgf9 acting as a meiosis-inhibiting substance and Kl acting as a promoter of the differentiation process. To understand the molecular mechanisms that might underlie this difference, we tried to dissect the intracellular signaling elicited by these two growth factors. We found that both Fgf9 and Kl stimulate Erk1/2 activation in Kit+ (differentiating) spermatogonia, even though with different time courses, whereas Kl, but not Fgf9, elicits activation of the Pi3k-Akt pathway. Sustained Erk1/2 activity promoted by Fgf9 is required for induction of the autocrine Cripto-Nodal-Smad2/3 signaling loop in these cells. Nodal signaling, in turn, is essential to mediate Fgf9 suppression of the meiotic program, including inhibition of Stra8 and Scp3 expression and induction of the meiotic gatekeeper Nanos2. On the contrary, sustained activation of the Pi3k-Akt pathway is required for the induction of Stra8 expression elicited by Kl and retinoic acid. Moreover, we found that Kl treatment impairs Nodal mRNA expression and Fgf9-mediated Nanos2 induction, reinforcing the antagonistic effect of these two growth factors on the meiotic fate of male germ cells.

Disease-free survival according to degree of HER2 amplification for patients treated with adjuvant chemotherapy with or without 1 year of trastuzumab: the HERA Trial

PURPOSE

To determine whether (1) immunohistochemical (IHC) HER2 status (ie, 2+ or 3+), (2) degree of fluorescence in situ hybridization (FISH) amplification according to (2a) HER2/CEP17 ratio or (2b) HER2 gene copy number, or (3) polysomy significantly influenced clinical outcome for patients with human epidermal growth factor receptor 2 (HER2) -positive breast cancer enrolled in the Herceptin Adjuvant trial of trastuzumab versus no trastuzumab administered after completion of chemotherapy.

PATIENTS AND METHODS

IHC and/or FISH analyses were performed locally and required central confirmation as indicating HER2 positivity for trial entry. FISH data from the central HER2 analysis on patients in the 1-year trastuzumab and no trastuzumab arms were assessed in relation to disease-free survival (DFS) after a median 2 years of follow-up.

RESULTS

Central FISH results were available for 2,071 (61%) of the 3,401 patients randomized to the 2 arms. Among patients with FISH-positive disease, (1) the hazard ratios for trastuzumab versus no trastuzumab were 0.56 (95% CI, 0.32 to 0.99) for locally IHC2+ cases (n = 340) and 0.80 (95% CI, 0.40 to 1.61) for centrally IHC2+ cases (n = 299). There was no significant prognostic relationship between (2a) HER2 FISH ratio, (2b) HER2 copy number, or (3) polysomy and DFS in the control arm or predictive relationship defining differential benefit from trastuzumab.

CONCLUSION

There was no evidence for reduced benefit of trastuzumab in HER2 IHC2+FISH+ cases. The degree of HER2 amplification does not influence prognosis or benefit from adjuvant trastuzumab in patients treated with prior adjuvant chemotherapy.

Long-term benefit of high-dose epirubicin in adjuvant chemotherapy for node-positive breast cancer: 15-year efficacy results of the Belgian multicentre study

PURPOSE

The 4-year results of this trial demonstrated that a higher dose of epirubicin with cyclophosphamide (HEC) is superior to a lower dose of epirubicin, 60 mg/m(2) (EC), for event-free survival (EFS; 27% reduction), but is not superior to classical oral cyclophosphamide, methotrexate, and fluorouracil (CMF) in the adjuvant treatment of node-positive breast cancer. Herein we report the 15-year data on efficacy and long-term toxicity of this three-arm Belgian multicenter trial.

PATIENTS AND METHODS

Between March 1988 and December 1996, 777 eligible patients were randomly assigned to six cycles of CMF, eight cycles of EC, or eight cycles HEC.

RESULTS

The 15-year EFS was 45% for patients who received CMF, 39% for patients who received EC, and 50% for patients who received HEC. The hazard ratios (HR) were 0.77 for HEC versus EC (95% CI, 0.60 to 0.98; P = .03), 0.90 for HEC versus CMF (P = .39), and 0.86 for EC versus CMF (P = .21). No difference in overall survival (OS) was seen. Cardiac toxicity was more frequent with HEC than with CMF (11 patients v 1 patient; P = .006), but no more than with EC (P = .21).

CONCLUSION

Treatment with HEC demonstrated superior EFS when compared with lower-dose epirubicin. However, we do not recommend the use of HEC regimen in daily clinical practice, mainly because of the higher risk of cardiotoxicity related to the cumulative doses of epirubicin and the lack of superiority of anthracyclines over CMF in our study.

Is risk of central nervous system (CNS) relapse related to adjuvant taxane treatment in node-positive breast cancer? Results of the CNS substudy in the intergroup Phase III BIG 02-98 Trial

BACKGROUND

Breast cancer central nervous system (CNS) metastases are an increasingly important problem because of high CNS relapse rates in patients treated with trastuzumab and/or taxanes.

PATIENTS AND METHODS

We evaluated data from 2887 node-positive breast cancer patients randomised in the BIG 02-98 trial comparing anthracycline-based adjuvant chemotherapy (control arms) to anthracycline-docetaxel-based sequential or concurrent chemotherapy (experimental arms). After a median follow-up of 5 years, 403 patients had died and detailed information on CNS relapse was collected for these patients.

RESULTS

CNS relapse occurred in 4.0% of control patients and 3.7% of docetaxel-treated patients. CNS relapse occurred in 27% of deceased patients in both treatment groups. CNS relapse was usually accompanied by neurologic symptoms (90%), and 25% of patients with CNS relapse died without evidence of extra-CNS relapse. Only 20% of patients survived 1 year from the diagnosis of CNS relapse. Prognosis of CNS relapse was worse for patients with meningeal carcinomatosis when compared with brain metastases. Unexpected findings included a higher rate of positive cerebrospinal fluid cytology (8% versus 3%) and more frequent use of magnetic resonance imaging for diagnosis (47% versus 30%) in the docetaxel-treated patients.

CONCLUSION

There is no evidence that adjuvant docetaxel treatment is associated with an increased frequency of CNS relapse.

Potential Predictive Value of Bcl-2 for Response to Tamoxifen in the Adjuvant Setting of Node-Positive Breast Cancer

Approximately 50% of patients with estrogen receptor (ER)-positive breast cancer (BC) and 70%-80% of patients with ER-positive and progesterone receptor (PgR)-positive BC respond to hormonal therapy. Additional predictive markers are needed. A group of 287 patients with ER- and/or PgR-positive tumors was selected from 804 patients previously enrolled in a multicenter phase III trial. Bcl-2 expression was evaluated and correlated with response to adjuvant tamoxifen and survival. Estrogen receptor and PgR were determined by biochemical means and Bcl-2 by immunohistochemistry. With a median follow-up of 76 months (95 relapses and 60 deaths), of the 287 patients with, 187 (65%) had Bcl-2-positive tumors and 78 of these patients received tamoxifen. Of the 100 patients with Bcl-2-negative disease, 51 received tamoxifen and 49 regular follow-up. Using patients treated with tamoxifen as a reference, a univariate analysis of disease-free interval for patients who did not receive tamoxifen showed a hazard ratio (HR) of 1.42 (95% CI, 0.82-2.44; P = 0.21) for patients with Bcl-2-positive disease and a HR of 1.05 (95% CI, 0.55-1.99; P = 0.89) for patients with Bcl-2-negative disease (P = 0.48). After adjusting for number of positive lymph nodes, degree of receptor and PgR positivity, and type of surgery, the HRs were 1.54 (95% CI, 0.87-2.73; P = 0.14) for Bcl-2-positive disease and 1.05 (95% CI, 0.52-2.11; P = 0.88) for Bcl-2-negative disease. Despite its being a retrospective nonrandomized study with a relatively low number of patients, our results suggest that Bcl-2 deserves further evaluation as a predictive factor of sensitivity to tamoxifen.

Molecular mechanisms utilized by alternative c-kit gene products in the control of spermatogonial proliferation and sperm-mediated egg activation

The c-kit proto-oncogene plays a dual role in the control of male fertility in mice through two alternative gene products: (1). c-kit [the transmembrane tyrosine kinase receptor for stem cell factor (SCF)], which is expressed and functional in differentiating spermatogonia of the postnatal testis, in which c-kit is essential for pre-meiotic proliferation; and (2). tr-kit, an intracellular protein which is specifically accumulated during spermiogenesis through the use of an alternative intronic promoter, and which is able to trigger mouse egg activation when microinjected into the cytoplasm of metaphase II arrested oocytes. Here, we summarize the most recent findings about the molecular pathways through which c-kit regulates cell cycle progression in mitotic germ cells, and those through which sperm-derived tr-kit triggers parthenogenetic completion of meiosis II and pronuclear formation in microinjected mouse eggs.

Molecular biology tools for dissecting sexual behavior

The tools of molecular biology have just begun to demonstrate the role of genes in controlling sexual behavior and how hormones can influence sexual and reproductive motivation by controlling gene expression. In this review article the use of the new term "molecular sexology" is proposed to indicate the growing evidence that molecular biology techniques can be a useful tool not only to understand the genetic bases of the animal (and soon human) sexual behavior, but also in order to provide the rationale of the use of advanced therapeutic approaches, such as gene transfer, to the symptoms and diseases of sexuality.

3-year results of docetaxel-based sequential and combination regimens in the adjuvant therapy of node-positive breast cancer: a pilot study

BACKGROUND

Docetaxel has proven efficacy in metastatic breast cancer. In this pilot study, we explored the efficacy/feasibility of docetaxel-based sequential and combination regimens as adjuvant therapy of node-positive breast cancer.

PATIENTS AND METHODS

From March 1996 till March 1998, four consecutive groups of patients with stages II and III breast cancer, aged < or = 70 years, received one of the following regimens: a) sequential Doxorubicin (A) --> Docetaxel (T) --> CMF (Cyclophosphamide+Methotrexate+5-Fluorouracil): A 75 mg/m q 3 wks x 3, followed by T100 mg/m2 q 3 wks x 3, followed by i.v. CMF Days 1+8 q 4 wks x 3; b) sequential accelerated A --> T --> CMF: A and T administered at the same doses q 2 wks with Lenograstin support; c) combination therapy: A 50 mg/m2 + T 75 mg/m2 q 3 wks x 4, followed by CMF x 4; d) sequential T --> A --> CMF: T and A, administered as in group a), with the reverse sequence. When indicated, radiotherapy was administered during or after CMF, and Tamoxifen after CMF.

RESULTS

Ninety-three patients were treated. The median age was 48 years (29-66) and the median number of positive axillary nodes was 6 (1-25). Tumors were operable in 94% and locally advanced in 6% of cases. Pathological tumor size was >2 cm in 72% of cases. There were 21 relapses, (18 systemic, 3 locoregional) and 11 patients (12%) have died from disease progression. At median follow-up of 39 months (6-57), overall survival (OS) was 87% (95% CI, 79-94%) and disease-free survival (DFS) was 76% (95% CI, 67%-85%).

CONCLUSION

The efficacy of these docetaxel-based regimens, in terms of OS and DFS, appears to be at least as good as standard anthracycline-based adjuvant chemotherapy (CT), in similar high-risk patient populations.

HER-2 amplification and topoisomerase IIalpha gene aberrations as predictive markers in node-positive breast cancer patients randomly treated either with an anthracycline-based therapy or with cyclophosphamide, methotrexate, and 5-fluorouracil

PURPOSE

The purpose of this study is to evaluate HER-2 and topoisomerase IIalpha (topo IIalpha) as candidates for predicting the activity of anthracyclines in the adjuvant treatment of breast cancer patients.

EXPERIMENTAL DESIGN

In this study, we evaluated HER-2 and topo IIalpha gene aberrations by fluorescence in situ hybridization in a series of 430 primary breast cancer samples. Samples came from node-positive breast cancer patients randomly treated either with one of two anthracycline-based regimens [full-dose epirubicin-cyclophosphamide (HEC) and moderate-dose epirubicin-cyclophosphamide (EC)] or with cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) in the context of a Phase III adjuvant therapy trial. Event-free survival comparisons were performed between the three study arms in the subgroups of HER-2-amplified and nonamplified tumors. An explorative analysis was also performed to evaluate the predictive value of topo IIalpha in the cohort of HER-2-amplified patients.

RESULTS

HER-2 amplification was observed in 73 of the 354 evaluable samples (21%), whereas topo IIalpha amplification was found in 23 of the 61 evaluable HER-2-amplified tumors (38%). The three event-free survival comparisons were CMF versus HEC, CMF versus EC, and EC versus HEC. Hazard ratios (HRs) and 95% confidence intervals (CIs) were as follows: (a) CMF versus HEC, HR = 1.42 for HER-2-amplified tumors (95% CI, 0.54-3.76; P = 0.48) and 0.84 for HER-2-nonamplified tumors (95% CI, 0.49-1.44; P = 0.53); (b) CMF versus EC, HR = 1.65 for HER-2-amplified tumors (95% CI, 0.66-4.13; P = 0.29) and 0.66 for HER-2-nonamplified tumors (95% CI, 0.39-1.10; P = 0.11); and (c) EC versus HEC, HR = 0.93 for HER-2-amplified tumors (95% CI, 0.31-2.77, P = 0.90) and 1.33 for HER-2-nonamplified tumors (95% CI, 0.82-2.14; P = 0.25). Observed HRs suggest that the anthracycline-based therapy could be more effective than CMF in the subgroup of HER-2-amplified patients, whereas treatments could be equally active in the HER-2-nonamplified cohort. topo IIalpha evaluation suggests that the superiority of anthracyclines over CMF in HER-2-amplified patients could be confined to the subgroup of topo IIalpha-amplified tumors.

CONCLUSIONS

HER-2 could have a predictive value for the activity of anthracycline-based regimens in the adjuvant therapy of breast cancer patients. The predictive value of HER-2 would most likely be related to the concomitant amplification of the topo IIalpha gene.

The feasibility of classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF) for pre- and post-menopausal node-positive breast cancer patients in a Belgian multicentric trial: a study of consistency in relative dose intensity (RDI) and cumulative doses across institutions

BACKGROUND

Classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF) including oral cyclophosphamide is still considered an important adjuvant chemotherapy regimen in patients with early breast cancer (BC). Concern has been raised regarding the feasibility of this regimen, especially in postmenopausal patients.

PATIENTS AND METHODS

254 pre- and post-menopausal node-positive BC patients aged < or = 70 years received six cycles of CMF in the context of a Belgian multicentric phase III trial of adjuvant chemotherapy. CMF dose and schedule were as follows: cyclophosphamide 100 mg/m2 p.o. on days 1 to 14, methotrexate 40 mg/m2 intravenously (i.v.) on days 1 and 8, 5-fluorouracil 600 mg/ml i.v. on days 1 and 8; cycles q. 28 days. The relative dose intensity (RDI) was calculated as the ratio between the delivered DI and the planned DI. We also analysed the RDI in two subgroups of patients with age > or = 50 years or < 50 years.

RESULTS

Overall, the percentage of patients ending the six cycles of the planned CMF regimen was 90%. The mean RDI achieved in the population of 254 patients was 90% (range 8% to 129%). The subgroup analysis of patients aged > or = 50 years and < 50 years showed that 81% and 76% of patients, respectively, received > or = 80% of the planned chemotherapy dose intensity (P = 0.33). No statistically significant difference was found between the percentage of patients who received a RDI < 80% and the participating institutions (P = 0.50).

CONCLUSIONS

The classical CMF regimen was a feasible regimen in the context of a multicentric trial, in which academic institutions as well as community hospitals participated. No substantial differences in RDI and cumulative doses were found in relation to a patient's age and the participating institution.

Signaling through extracellular signal-regulated kinase is required for spermatogonial proliferative response to stem cell factor

In vitro addition of stem cell factor (SCF) to c-kit-expressing A(1)-A(4) spermatogonia from prepuberal mice stimulates their progression into the mitotic cell cycle and significantly reduces apoptosis in these cells. SCF addition results in a transient activation of extracellular signal-regulated kinases (Erk)1/2 as well as of phosphatidylinositol 3-kinase (PI3K)-dependent Akt kinase. These events are followed by a rapid re-distribution of cyclin D3, which becomes predominantly nuclear, whereas its total cellular amount does not change. Nuclear accumulation of cyclin D3 is coupled to transient activation of the associated kinase activity, assayed using the retinoblastoma protein (Rb) as a substrate. These events were followed by a transient accumulation of cyclin E, stimulation of the associated histone H1-kinase activity, a delayed accumulation of cyclin A2, and Rb hyper-phosphorylation. All the events associated with SCF-induced cell cycle progression are inhibited by the addition of either a PI3K inhibitor or a mitogen-activated protein-kinase kinase (MEK) inhibitor, indicating that both MEK and PI3K are essential for c-kit-mediated proliferative response. On the contrary, the anti-apoptotic effect of SCF is not influenced by the separate addition of either MEK or PI3K inhibitors. Thus, SCF effects on mitogenesis and survival in c-kit expressing spermatogonia rely on different signal transduction pathways.

HER-2 and topo-isomerase IIalpha as predictive markers in a population of node-positive breast cancer patients randomly treated with adjuvant CMF or epirubicin plus cyclophosphamide

BACKGROUND

The predictive role of HER-2 in node-positive breast cancer patients receiving CMF or an anthracycline-based adjuvant therapy remains unclear. In addition, topo-isomerase II alpha (topo IIalpha), as the cellular target of anthracyclines, might have value as a predictive marker.

PATIENTS AND METHODS

Four hundred eighty-one archival primary tumor samples were collected among 777 patients entered into a multicenter phase III trial comparing classical CMF with epirubicin cyclophosphamide (HEC) as adjuvant therapy of node-positive breast cancer. HER-2 was evaluated by immunohistochemistry (IHC) using different antibodies (Abs). Topo IIalpha was evaluated by IHC using the Ab KiS 1. In each subgroup of patients identified by HER-2 and topo IIalpha, adjusted hazard ratios for event-free survival (EFS) and the corresponding 95% confidence intervals have been calculated for the different study comparisons. An interaction test has been performed to investigate the role of HER-2 and topo IIalpha as predictive markers.

RESULTS

When HER-2 was evaluated by CB-11 and 4D5 mAbs, the EFS adjusted hazard ratios (HR) for the main study comparison HEC vs. CMF were: HER-2 positive: 0.33 (95% confidence interval (95% CI): 0.09 1.27, P = 0.08), HER-2 negative: 1.16 (95%, CI: 0.71-1.90, P = 0.56); the P-value for the interaction test was 0.10. When HER-2 was evaluated by TAB-250 + pAbl Abs, the adjusted HR for the same comparison were: HER-2 positive: 1.06 (95% CI: 0.45-2.52, P = 0.90), HER-2 negative: 0.99 (95% CI: 0.58-1.68, P = 0.97); the P-value for the interaction test was 0.84. With regard to topo IIalpha, the adjusted HR for the EFS comparison HEC vs. CMF were: topo IIalpha positive: 0.66 (95% CI: 0.32-1.36, P = 0.25), topo IIalpha negative: 1.26 (95% CI: 0.63-2.50, P = 0.51); the P-value for the interaction test was 0.13.

CONCLUSIONS

This study suggests that in node-positive breast cancer patients randomly treated with CMF or an epirubicin-based regimen, the predictive value of HER-2 may vary according to the Abs used in the immunohistochemistry assay. In addition, the study supports the concept that topo IIalpha might be involved in the determination of tumor responsiveness to an anthracycline-based adjuvant therapy.

Intermittent catheterization with a prelubricated catheter in spinal cord injured patients: a prospective randomized crossover study

PURPOSE

We compared the safety and patient acceptance of a conventional Nélaton and a prelubricated nonhydrophilic catheter in 18 spinal cord injured patients on intermittent catheterization.

MATERIALS AND METHODS

In a prospective crossover study each catheter was used for 7 weeks and the initial course was randomized. Urinalysis and urine culture were performed at 2, 4 and 7 weeks. Urethral trauma was evaluated by urethral cell count on the surface of each catheter used on the last day of each study period. Patient satisfaction was assessed at the end of the study by a questionnaire using multiple visual analog scales.

RESULTS

Urinary tract infection was identified in 12 and 4 patients on a Nélaton and a prelubricated nonhydrophilic catheter (p = 0.03), while asymptomatic bacteruria was identified in 18 and 8 (p = 0.0244), respectively. The mean urethral cell count plus or minus standard deviation on the catheter surface was 6.7 +/- 2.8 x 10(4) and 15.1 +/- 8.9 x 10(4) for the prelubricated nonhydrophilic and the Néelaton catheter, respectively (p = 0.01). The prelubricated nonhydrophilic catheter resulted in a better mean satisfaction score than the Nélaton catheter (2.33 +/- 1.06 versus 4.72 +/- 2.13, p = 0.022). Urethral bleeding was reported in 2 patients during the study period while using the Nélaton catheter.

CONCLUSIONS

The prelubricated nonhydrophilic catheter is a safe, effective and comfortable option in spinal cord injured patients on intermittent self-catheterization.

Phase III trial comparing two dose levels of epirubicin combined with cyclophosphamide with cyclophosphamide, methotrexate, and fluorouracil in node-positive breast cancer

PURPOSE

To compare a full-dose epirubicin-cyclophosphamide (HEC) regimen with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) therapy and with a moderate-dose epirubicin-cyclophosphamide regimen (EC) in the adjuvant therapy of node-positive breast cancer.

PATIENTS AND METHODS

Node-positive breast cancer patients who were aged 70 years or younger were randomly allocated to one of the following treatments: CMF for six cycles (oral cyclophosphamide); EC for eight cycles (epirubicin 60 mg/m(2), cyclophosphamide 500 mg/m(2); day 1 every 3 weeks); and HEC for eight cycles (epirubicin 100 mg/m(2), cyclophosphamide 830 mg/m(2); day 1 every 3 weeks).

RESULTS

Two hundred fifty-five, 267, and 255 eligible patients were treated with CMF, EC, and HEC, respectively. Patient characteristics were well balanced among the three arms. One and three cases of congestive heart failure were reported in the EC and HEC arms, respectively. Three cases of acute myeloid leukemia were reported in the HEC arm. After 4 years of median follow-up, no statistically significant differences were observed between HEC and CMF (event-free survival [EFS]: hazards ratio [HR] = 0.96, 95% confidence interval [CI], 0.70 to 1.31, P =.80; distant-EFS: HR = 0.97, 95% CI, 0.70 to 1.34, P =.87; overall survival [OS]: HR = 0.97, 95% CI, 0.65 to 1.44, P =.87). HEC is more effective than EC (EFS: HR = 0.73, 95% CI, 0.54 to 0.99, P =.04; distant-EFS: HR = 0.75, 95% CI, 0.55 to 1.02, P =.06; OS HR = 0.69, 95% CI, 0.47 to 1.00, P =.05).

CONCLUSION

This three-arm study does not show an advantage in favor of an adequately dosed epirubicin-based regimen over classical CMF in the adjuvant therapy of node-positive pre- and postmenopausal women with breast cancer. Moreover, this study confirms that there is a dose-response curve for epirubicin in breast cancer adjuvant therapy.

Evaluation of HER2, p53, bcl-2, topoisomerase II-alpha, heat shock proteins 27 and 70 in primary breast cancer and metastatic ipsilateral axillary lymph nodes

BACKGROUND

Breast cancer is a heterogeneous disease. Predictive biological markers (BM) of responsiveness to therapy need to be identified. Evaluation of BM is mainly done at the primary site. However, in the adjuvant therapy of breast cancer, the main goal is control of micrometastases. It is still unknown whether heterogeneity in the expression of BM between the primary site and its micrometastases exists.

OBJECTIVE

To evaluate the expression of some BM with potential predictive value from the primary breast cancer site and metastatic ipsilateral axillary lymph nodes.

PATIENTS AND METHODS

Focality (percentage of positive cells) and intensity staining scores were evaluated for each marker. Freshly cut sections (4 microm) from embedded blocks of breast cancer fixed in formalin or bouin were put onto superfrost slides (Menzel-Gläser). Protein expression was evaluated immunohistochemically (IHC) using monoclonal antibodies against: topo II-alpha (clone KiS1, 1 microg/ml, Roche) with a trypsine pre-treatment (P); HSP27 (clone G3.1, 1/60, Biogenex), HSP70 (clone BRM.22, 1/80, Biogenex) and HER2 (clone CB11, 1/40, Novocastra; without P); p53 (clone D07, 1/750, Dako) and bcl-2 (clone 124, 1/60, Dako) with citrate buffer as P.

RESULTS

Overall, the percentage of discordant marker status in the primary tumour and its metastatic lymph nodes was 2% for HER2, 6% for p53, 15% for bcl-2, 19% for topoisomerase II-alpha, 24% for HSP27 and 30% for HSP70. For the subgroup of patients with positive BM in the primary tumour, the percentage of discordance was 6% for HER2, 7% for p53, 14% for bcl-2, 19% for HSP70, 21% for topoisomerase II-alpha and 36% for HSP27. For the subgroup of patients with positive BM in the lymph nodes, the percentage of discordance was 9% for bcl-2, 15% for HER2 and p53, 21% for topoisomerase II-alpha, 22% for HSP27 and 25% for HSP70.

CONCLUSIONS

1) No biological marker had 100% concordant results. 2) Although some discordant cases might be explained by the limitations of the IHC technique, future studies aiming to evaluate the predictive value of BM in the adjuvant therapy of breast cancer should take into account a possible difference in BM expression between the primary and the metastatic sites.

The role of stem cell factor and of alternative c-kit gene products in the establishment, maintenance and function of germ cells

The c-kit gene plays a fundamental role during the establishment, the maintenance and the function of germ cells. In the embryonal gonad the c-kit tyrosine kinase receptor and its ligand Stem Cell Factor (SCF) are required for the survival and proliferation of primordial germ cells. In the postnatal animal, c-kit/SCF are required for the production of the mature gametes in response to gonadotropic hormones, i.e. for the survival and/or proliferation of the only proliferating germ cells of the testis, the spermatogonia, and for the growth and maturation of the oocytes. Finally, a truncated c-kit product, tr-kit, specifically expressed in post-meiotic stages of spermatogenesis and present in mature spermatozoa, causes parthenogenetic activation when microinjected into mouse eggs, suggesting that it might play a role in the final function of the gametes, fertilization.

Doxorubicin followed by docetaxel versus docetaxel followed by doxorubicin in the adjuvant treatment of node positive breast cancer: results of a feasibility study

BACKGROUND

Doxorubicin (A) and Docetaxel (T) are amongst the most active agents in breast cancer treatment. The impact of drug sequencing is an issue still under evaluation.

OBJECTIVE

To evaluate the feasibility and tolerability of two A and T-based sequential regimens, in which the sequence of drug administration was reversed.

METHODS

The study included patients pts aged < or = 70 years, with operable node positive breast cancer. Two consecutive groups of patients received one of the following regimens: 1) Sequential A-->T-->CMF: Doxorubicin 75 mg/m2, i.v., day 1, q3wks x 3 cycles, followed by Docetaxel 100 mg/m2, i.v., day 1, q3wks x 3 cycles, followed by i.v. CMF days 1 and 8 q4wks x 3 cycles. 2) Sequential T-->A-->CMF: same doses for Doxorubicin and Docetaxel but reverse sequence of administration, followed by oral CMF (CPA 100 mg/m2, oral, days 1-14 + MTX 40 mg/m2, i.v., days 1 and 8 + 5FU 600 mg/m2, i.v., days 1 and 8, q4wks). An analysis of treatment administration and toxicity was performed for the first six cycles of CT, in the two treatment groups.

RESULTS

Group 1 with 20 patients and group 2 with 14 patients were balanced in terms of patient and tumour characteristics. There was one early treatment discontinuation in each group due to toxicity (one allergic and one skin reaction to docetaxel). Median relative dose intensity was 100% for both drugs in both groups. The most relevant side effects were (overall incidence, group 1 vs group 2): Myalgia: 45% vs 72%; Arthralgia: 15% vs 57%; Skin: 35% vs 57%; Neurosensory: 55% vs 64%; Stomatitis 65% vs 36%; conjunctivitis 25% vs 57%; Neutropenic Fever 20% vs 21% and Fatigue 80% vs 93%. Grade 3/4 adverse events' rate was low in the two groups.

CONCLUSIONS

1) Both sequences were estimated feasible due to the optimal treatment administration and limited incidence of G3-G4 side effects. 2) The concomitant use of lenograstin might partially explain the reported incidence of myalgia and arthralgia. 3) No conclusion can be drawn on the most tolerable regimen due to the limited number of patients.

Role of c-kit in mammalian spermatogenesis

The tyrosine-kinase receptor c-kit and its ligand, stem cell factor (SCF), are essential for the maintenance of primordial germ cells (PGCs) in both sexes. However, c-kit and a post-meiotic-specific alternative c-kit gene product play important roles also during post-natal stages of spermatogenesis. In the adult testis, the c-kit receptor is re-expressed in differentiating spermatogonia, but not in spermatogonial stem cells, whereas SCF is expressed by Sertoli cells under FSH stimulation. SCF stimulates DNA synthesis in type A spermatogonia cultured in vitro, and injection of anti-c-kit antibodies blocks their proliferation in vivo. A point mutation in the c-kit gene, which impairs SCF-mediated activation of phosphatidylinositol 3-kinase, does not cause any significant reduction in PGCs number during embryonic development, nor in spermatogonial stem cell populations. However males are completely sterile due to a block in the initial stages of spermatogenesis, associated to abolishment of DNA-synthesis in differentiating A1-A4 spermatogonia. With the onset of meiosis c-kit expression ceases, but a truncated c-kit product, tr-kit, is specifically expressed in post-meiotic stages of spermatogenesis, and is accumulated in mature spermatozoa. Microinjection of tr-kit into mouse eggs causes their parthenogenetic activation, suggesting that it might play a role in the final function of the gametes, fertilization.

Glial cell line-derived neutrotrophic factor and neurturin can act as paracrine growth factors stimulating DNA synthesis of Ret-expressing spermatogonia

Glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) are related growth factors which exert trophic effects on several neuronal populations and developing kidney. GDNF-family ligands interact with membrane receptors designated GFRalphas which, in turn, mediate stimulation of the Ret receptor tyrosine kinase. Here we show that Ret, GFRalpha-1 (the GDNF receptor), and GFRalpha-2 (the NTN receptor) are expressed by testicular germ cells, while GDNF and NTN are expressed by Sertoli cells. Both GDNF and NTN stimulate DNA synthesis in spermatogonia. Furthermore, Ret, ligands and co-receptors are expressed in germ cell tumors. Thus, GDNF-family ligands may act as paracrine factors in spermatogenesis and this circuit may be active in germ cell tumors.

A feasibility study evaluating docetaxel-based sequential and combination regimens in the adjuvant therapy of node-positive breast cancer

BACKGROUND AND PURPOSE

Docetaxel is an active agent in the treatment of metastatic breast cancer. We evaluated the feasibility of docetaxel-based sequential and combination regimens as adjuvant therapies for patients with node-positive breast cancer.

PATIENTS AND METHODS

Three consecutive groups of patients with node-positive breast cancer or locally-advanced disease, aged < or = 70 years, received one of the following regimens: a) sequential A-->T-->CMF: doxorubicin 75 mg/m2 q 3 weeks x 3, followed by docetaxel 100 mg/m2 q 3 weeks x 3, followed by i.v. CMF days 1 + 8 q 4 weeks x 3; b) sequential accelerated A-->T-->CMF: A and T were administered at the same doses q 2 weeks; c) combination therapy: doxorubicin 50 mg/m2 + docetaxel 75 mg/m2 q 3 weeks x 4, followed by CMF x 4. When indicated, radiotherapy was administered during or after CMF, and tamoxifen started after the end of CMF.

RESULTS

Seventy-nine patients have been treated. Median age was 48 years. A 30% rate of early treatment discontinuation was observed in patients receiving the sequential accelerated therapy (23% during A-->T), due principally to severe skin toxicity. Median relative dose-intensity was 100% in the three treatment arms. The incidence of G3-G4 major toxicities by treated patients, was as follows: skin toxicity a: 5%; b: 27%; c: 0%; stomatitis a: 20%; b: 20%; c: 3%. The incidence of neutropenic fever was a: 30%; b: 13%; c: 48%. After a median follow-up of 18 months, no late toxicity has been reported.

CONCLUSIONS

The accelerated sequential A-->T-->CMF treatment is not feasible due to an excess of skin toxicity. The sequential non accelerated and the combination regimens are feasible and under evaluation in a phase III trial of adjuvant therapy.

Electromotive versus passive diffusion of mitomycin C into human bladder wall: concentration-depth profiles studies

The objectives of these investigations were: (a) to make a preliminary study to assess concentration-depth profiles of mitomycin C (MMC) in the bladder wall at specified time intervals after passive diffusion (PD); and (b) to conduct a major study to compare concentration-depth profiles after PD and electromotive drug administration (EMDA) of MMC. Full thickness sections of viable human bladder wall were placed in two-chamber cells with urothelium exposed to donor compartments containing 40 mg of MMC in 100 ml of 0.96% NaCl solutions and with serosa-facing receptor compartments containing 0.9% NaCl solutions. In the preliminary study during each of nine experimental sessions, five sections of bladder wall were individually exposed to MMC for either 5, 15, 30, 45, or 60 min. In the major study, an anode and a cathode were sited in the donor and receptor compartments, and 14 paired experiments--current (20 mA)/no current--were conducted over a 30-min period. Bladder wall sections were cut serially into 40-microm slices parallel to the urothelium and analyzed by high-performance liquid chromatography for MMC concentration (microg/g wet tissue weight). Tissue viability and morphology and MMC stability were assessed by trypan-blue exclusion test, histological examination, and mass spectrometry analysis. In the preliminary study (PD only), mean MMC concentrations (microg) at 5, 15, 30, 45, and 60 min were: (a) for urothelium, 15.3, 60.0, 58.2, 60.1, and 57.8, respectively; (b) for lamina propria, 2.2, 18.9, 19.3, 16.1, and 17.3, respectively; and (c) for muscularis, 0.4, 2.0, 1.8, 1.3, and 2.4, respectively. In the comparative study, MMC concentrations and coefficients of variation (CV) were as follows: (a) for urothelium after PD, 46.6 with CV = 69%, and after EMDA, 170.0 with CV = 43% (P < 0.0001); (b) for lamina propria after PD, 16.1, with CV = 60%, and after EMDA, 65.6 with CV = 29% (P < 0.0001); and (c) for muscularis after PD, 1.9 with CV = 82%, and after EMDA, 15.9 with CV = 82% (P < 0.0005). All of the bladder sections remained viable, and the chemical structure of MMC was unchanged. It was concluded that EMDA significantly enhances MMC transport into all of the layers of the bladder wall, and sections of viable human bladder are a reliable tool for assessing different modes of drug delivery.

Identification of a promoter region generating Sry circular transcripts both in germ cells from male adult mice and in male mouse embryonal gonads

The mouse testis determining gene Sry is expressed in somatic cells of the differentiating male gonad as a linear transcript, encoding a transcription factor containing an HMG box. In the adult mouse testis, Sry expression occurs in meiotic and postmeiotic germ cells. The mouse genomic Sry locus is characterized by two arms of a large inverted repeat, flanking a unique region that, between an acceptor and a donor splice site, contains a single exon encoding the Sry protein. In germ cells from the adult mouse testis, Sry RNA is a circular molecule, which is generated by an inverted splicing event that utilizes the above-mentioned splice sites. Thus, a circular exon is spliced out starting from a large linear RNA precursor containing both arms of the inverted repeat, which pair and generate a large stem-loop structure. Using reverse transcription-polymerase chain reaction and an RNase protection assay, we have now mapped the 5' end of this precursor RNA in the 5' arm of the inverted repeat. Gel mobility shift assay and in vitro transcription with nuclear extracts from adult germ cells further confirm that a region immediately 5' upstream of two transcriptional initiation sites of the precursor RNA contains a promoter sequence in which two consensus Sry binding sequences are specifically recognized by nuclear factors present in adult germ cells but not in Sertoli cells. We also show that the linear precursor of the Sry circular transcript and its splicing product are specifically expressed not only in adult germ cells but also in male embryonal gonads between 11.5 and 13.5 days postcoitum, immediately after the expression of the linear transcript starting from the unique region.

Electromotive delivery of mitomycin C into human bladder wall

The aim of this investigation was to establish an appropriate tissue pharmacokinetic model to compare concentrations of mitomycin C (MMC) in the human bladder wall after either passive delivery or electromotive administration (EMDA) and to evaluate the effects of EMDA on tissue morphology and MMC structure. Tissue sections of human bladder were inserted into two chamber cells with urothelium exposed to donor compartments containing MMC (10 mg in 100 ml of 0.24% NaCl solution) and an anode and with serosa exposed to receptor compartments containing 100 ml of 0.9% NaCl solution and a cathode. Fourteen paired experiments ("current 5 mA/no current") were conducted over 15 min; MMC tissue content was assessed by high-pressure liquid chromatography. Tissue viability and morphology and MMC stability were assessed by trypan blue exclusion test, tissue pH, histological analysis, and mass spectrometry analysis. MMC concentrations were increased, and variability in drug delivery rate was reduced in all tissue in samples exposed to electric current. Tissues were viable and undamaged histologically, and no MMC structural modification was observed. In conclusion, EMDA enhances administration of MMC into viable bladder wall tissue and reduces the variability in drug delivery rates.

A cell- and developmental stage-specific promoter drives the expression of a truncated c-kit protein during mouse spermatid elongation

In the postnatal testis, the c-kit transmembrane tyrosine-kinase receptor is expressed in type A spermatogonia, and its transcription ceases at the meiotic phase of spermatogenesis. Alternative, shorter c-kit transcripts are expressed in post-meiotic germ cells. These transcripts should encode a truncated version of the c-kit protein, lacking the extracellular, the transmembrane and part of the intracellular tyrosine-kinase domains. The 5′ end of the alternative c-kit transcripts maps within an intron of the mouse c-kit gene. We now show that this intron contains a promoter active in nuclear extracts of round spermatids, and that two discrete sequences upstream of the transcriptional start site bind spermatid-specific nuclear factors. Deletion of both these sequences abolishes activity of the promoter in vitro. We have also established that this promoter is functional in vivo, in a tissue-and cell-specific fashion, since intronic sequences drive the expression of the E. coli lacZ reporter gene in transgenic mice specifically in the testis. Transgene expression is confined to haploid germ cells of seminiferous tubules, starting from spermatids at step 9, and disappearing at step 13, indicating that cryptic promoter within the 16th intron of the mouse c-kit gene is active in a short temporal window at the end of the transcriptional phase of spermiogenesis. In agreement with these data, western blot experiments using an antibody directed against the carboxy-terminal portion of the mouse c-kit protein showed that a polypeptide, of the size predicted by the open reading frame of the spermatid-specific c-kit cDNA, accumulates in the latest stages of spermatogenesis and in epididymal spermatozoa. An immunoreactive protein of the same size can be produced in both eukaryotic and prokaryotic artificial expression systems.

Formestane: an effective first-line endocrine treatment for advanced breast cancer

Formestane, a new selective aromatase inhibitor devoid of severe side-effects, has been shown to be active in patients with advanced breast cancer. To investigate the clinical activity and endocrinological effects of formestane as a first-line treatment, 52 patients were administered two different doses: 24 received 250 mg formestane and 28 received 500 mg formestane i.m. fortnightly. All of the patients had a performance status of 2 or less (ECOG scale), 34 (65%) had a disease-free interval of at least 2 years and 21 (40%) were both oestrogen-receptor- and progesterone-receptor-positive; 20 patients received hormone and 13, received chemotherapeutical adjuvant treatment. Objective responses were obtained in 8 patients in the 250-mg group (33%; 95% CI: 14%-52%) and in 13 patients in the 500-mg group (46%; 95% CI: 28%-64%). The median response duration in the two groups was respectively 11 and 12 months. E2 serum levels of oestradiol had significantly (P < 0.001) decreased to more than 40% below the baseline value in both groups after 15 days of treatment, and remained unchanged thereafter. Local and systemic tolerability was satisfactory. We conclude that formestane is an effective and well-tolerated agent in previously untreated patients, and that these results should be confirmed by further studies.

Expression of the Xist gene in urogenital ridges of midgestation male embryos

We show by RT-PCR analysis that transcripts from the Xist gene, which is normally expressed from the inactive X chromosome of female somatic cells and postnatal male germ cells, are transiently expressed also in male embryos around the time of testis differentiation, mainly in somatic cells of urogenital ridges. In the postnatal testis, we find that Xist transcripts are mainly localized within the nucleus of haploid spermatids. These findings suggest that inactivation of the X-chromosome might occur not only in adult male germ cells, but also, transiently, in somatic cells of the male urogenital ridge. Both in the embryonal gonad and in differentiating germ cells Xist expression in males overlaps the pattern of expression of the testis determining gene Sry.

Developmental regulation of the thyroid hormone receptor alpha 1 mRNA expression in the rat testis

The multiplicity of thyroid hormone (TH) effects appears to be mediated by two TH receptors (THRs) encoded by two genes, alpha and beta, and, perhaps, by their various isoforms. The expression of THR beta is correlated with the presence of high affinity binding sites for TH, and all the mutations which cause the syndrome of generalized thyroid hormone resistance occur in THR beta. The function of THR alpha has not been clearly defined as yet. Another enigma in TH action is the effect on the testis. It has been shown that the testis of the adult rat does not respond to TH as measured by an increase in oxygen consumption. Furthermore, it has not been possible to demonstrate the presence of a nuclear high affinity binding site for TH in adult testis. To resolve these problems were measured the levels of THR alpha, its nonhormone binding variant, and THR beta mRNA in the testis at various stages of development. We discovered that the beta-message is absent at all times, whereas the alpha-message is expressed only from fetal through prepubertal stages and is absent in adult testis. THR alpha, but not the beta-mRNA, was detected in immature Sertoli cells in culture, and neither was found in adult Sertoli cell-enriched cultures. Furthermore, THR alpha and its variant mRNA was found, using in situ hybridization, in the seminiferous cords and seminiferous tubules of fetal and prepubertal testis.(ABSTRACT TRUNCATED AT 250 WORDS)

Testosterone levels as a marker of prognosis to goserelin treatment in metastatic breast cancer

Testosterone levels were measured in blood and urine of 35 premenopausal metastatic breast cancer patients before starting therapy with the gonadotrophin-releasing hormone (GnRH) analogue, goserelin. The aim of the study was to verify the reliability of testosterone measurement as a marker of prognosis. The time interval between starting therapy and progressive disease (time to progression) was chosen to assess prognosis. Univariate and multivariate analysis showed that only urinary testosterone levels were significantly associated with time to progression (Wald test 6.66, P = 0.01 for univariate and Wald test 7.93, P = 0.0049 for multivariate analysis), whereas no association was found for testosterone in blood. A statistical model is proposed to evaluate probability of progressive disease in relation to testosterone values in urine at different times. According to the model, the probability of progression decreases with increasing urinary testosterone values.

Stem cell factor and leukemia inhibitory factor promote primordial germ cell survival by suppressing programmed cell death (apoptosis)

Proliferating primordial germ cells (PGCs) isolated from mouse embryos soon after their arrival in the genital ridges would only survive in vitro at temperature of less than 30 degrees C (De Felici, M. and McLaren, A. (1983). Exp. Cell. Res. 144, 417–427; Wabik-Sliz, B. and McLaren, A. (1984). Exp. Cell. Res. 154, 530–536) or when co-cultured on cell feeder layers (Donovan, P. J., Stott, D., Godin, I., Heasman, J. and Wylie, C. C. (1986). Cell 44, 831–838; De Felici, M. and Dolci, S. (1991). Dev. Biol. 147, 281–284). In the present paper we report that mouse PGC death in vitro occurs with all the hallmarks of programmed cell death or apoptosis. We found that after 4–5 hours in culture many PGCs isolated from 12.5 dpc fetal gonads assumed a nuclear morphology and produced membrane bound fragments (apoptotic bodies) typical of apoptotic cells. In addition, PGCs in culture accumulated high level of tissue transglutaminase (tTGase; an enzyme that is induced and activated during apoptosis) and showed extensive degradation of DNA to oligonucleosomal fragments, which is characteristic of apoptosis. The physiological relevance of this mechanism of PGC death is supported by the finding that some PGCs undergoing apoptosis, as revealed by the high level of tTGase expression, were detected in the embryo. Most importantly, we show that the addition of stem cell factor (SCF) or leukemia inhibitory factor (LIF) to the culture medium, two cytokines known to favour PGC survival and/or proliferation in vitro, markedly reduced the occurrence of apoptosis in PGCs during the first hours in culture.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined action of stem cell factor, leukemia inhibitory factor, and cAMP on in vitro proliferation of mouse primordial germ cells

In the present paper we investigated the effects of stem cell factor/mastocyte growth factor (SCF/MGF), leukemia inhibitory factor/differentiating inhibitory activity (LIF/DIA) (two growth factors known to affect primordial germ cell growth in vitro) and forskolin (FRSK) (an activator of adenylate cyclase in many cell types) alone or in combination on the survival and proliferation of primordial germ cells (PGCs) obtained from 8.5, 10.5, and 11.5 days post coitum (dpc) mouse embryos and cultured without pre-formed cell feeder layers. The results showed that both at 1 and 3 days of culture the addition of 100 ng/ml SCF, 20 microM FRSK, or in some instances 20 ng/ml LIF alone caused a significant increase of PGC number as compared with controls. The highest effects were obtained when SCF and/or LIF were used together with FRSK. Moreover, we found that FRSK elevated cAMP levels in purified 11.5 dpc PGCs and that this compound, but not SCF and LIF, stimulated PGC proliferation, as assessed by 5-bromo-2'-deoxyuridin (BrdU) incorporation. These results suggest a mechanism of combined action of cAMP with SCF and/or LIF in the control of proliferation of mouse PGCs in vitro.

Proliferation of mouse primordial germ cells in vitro: a key role for cAMP

Two agents known to enhance the level of intracellular cAMP (dibutyryl cAMP and forskolin) markedly increase the number of 8.5, 10.5, and 11.5 days postcoitum (dpc) mouse primordial germ cells (PGCs) cultured on TM4 cell feeder layers. Forskolin (FRSK) caused a significant increase of PGC number also in monodispersed cell suspensions obtained from PGC-containing tissues of the three embryonic ages studied and in purified 11.5 dpc PGCs cultured without feeder layers. The addition to the culture medium of adenosine-3',5'-cyclic monophosphorothioate RP isomer (Rp-cAMPS, a competitive antagonist for cAMP-dependent protein kinases), significantly reduced the effects of FRSK. Last, FRSK stimulated PGC proliferation, as assessed by 5-bromo-2'-deoxyuridine incorporation. We conclude that cAMP-dependent mechanisms play a crucial role in the control of mitotic proliferation of mouse PGCs in culture.

Direct evidence that the mouse sex-determining gene Sry is expressed in the somatic cells of male fetal gonads and in the germ cell line in the adult testis

Reverse transcriptase polymerase chain reaction (RT-PCR) analysis shows that Sry mRNA is expressed in male fetal urogenital ridges from 12.5 day p.c. embryos, but not in enriched populations of primordial germ cells from the same embryos, indicating that Sry is expressed in the somatic cells of the embryonal gonad at the time of testis determination. We also show that, in the adult male mouse testis, Sry mRNA is expressed at high levels in meiotic and postmeiotic germ cells and, at much lower levels, also in Sertoli cells. Treatment with cyclic adenosine monophosphate (cAMP) analogs of cultured Sertoli cells from postnatal testis completely abolishes Sry mRNA expression.

Follicle-stimulating hormone induction of steel factor (SLF) mRNA in mouse Sertoli cells and stimulation of DNA synthesis in spermatogonia by soluble SLF

Follicle-stimulating hormone (FSH) and its intracellular mediator, cAMP, increase the mRNA levels for the Steel factor (SLF, the c-kit ligand) in cultured primary mouse Sertoli cells. The inductive effect of cAMP is more evident in cultures from 13-day-old animals than in cultures from 18-day-old animals. Analysis through the polymerase chain reaction (PCR) indicates that (Bu)2cAMP or FSH treatment increases the levels of the mRNAs for both the potentially soluble form and the transmembrane form of SLF in cultured Sertoli cells. The ratio between mRNAs encoding the potentially soluble form and the transmembrane form of SLF increases during postnatal testis development, and it is higher in cultured Sertoli cells with respect to total testis, suggesting that, under the in vitro conditions, SLF could be produced by Sertoli cells mainly as a soluble factor. Soluble recombinant SLF stimulates, in a dose-dependent fashion, thymidine incorporation in cultures of isolated germ cell populations enriched in the mitotic stages (spermatogonia), independently of the presence of serum, whereas cAMP analogs have no effect. Autoradiographic analysis shows that SLF selectively stimulates DNA synthesis in type A spermatogonia.