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J H Pinthus

Publications and source records attributed to J H Pinthus.

10 recordsLinked to original sources

Expression of cyclooxygenase-2 in Wilms tumor: immunohistochemical study using tissue microarray methodology.

PURPOSE: Cyclooxygenase-2, a key enzyme in prostaglandin biosynthesis, has been shown to be involved in the modulation of cell growth, inflammation and apoptosis. Its involvement in the development of several human neoplasms has also been documented as well as the significant antitumor effects of its inhibitors. To our knowledge cyclooxygenase-2 expression in Wilms tumor has not been studied. MATERIALS AND METHODS: A tissue microarray multitissue block was prepared from 14 samples of Wilms tumor, each from a different patient, from xenografts derived thereof, and from normal human lung, liver, renal cortex and medulla tissues as controls. Each sample was represented in the block by 3 or 4 cores 0.6 mm in diameter. After serial slicing to 4 mum the histological slides were stained with hematoxylin and eosin, and immunostained with anti-cyclooxygenase-2 antibodies. Immunostaining was graded semiquantitatively according to the percent of stained cells with the cytoplasmic pattern of staining and according to staining intensity. RESULTS: All authentic human pathological samples except 1 anaplastic Wilms tumor as well as Wilms tumor xenografts expressed cyclooxygenase-2 in all Wilms tumor cellular components except the stroma. Expression was also observed in Wilms tumor lung metastasis and in tumors that overgrew chemotherapy. In comparison, cyclooxygenase-2 expression in normal kidneys was less prominent than in Wilms tumor samples and it was confined to the tubular epithelium in the cortex and medulla. CONCLUSIONS: Cyclooxygenase-2 expression is characteristic of all nonanaplastic Wilms tumors at all stages. It is similar to the previously observed pan-expression of ErbB2 receptors in these tumors. The potential therapeutic role of cyclooxygenase-2 inhibitors should be evaluated for Wilms tumor.

Animals↗

Testicular fixation following torsion of the spermatic cord--does it guarantee prevention of recurrent torsion events?

PURPOSE: Patients with history of testicular torsion who have undergone orchiopexy may rarely present with acute scrotum due to recurrent episodes of torsion. Most of the reports in the literature regarding this scenario refer to the era when absorbable sutures were used for testicular fixation. Herein, we review our experience in recent years, focusing upon the surgical technique and sutures' material. MATERIALS AND METHODS: Between 1991 and 2003, 179 patients were operated on at our institute with the clinical diagnosis of unilateral testicular torsion. They ranged in age between neonates to 45 years old (average age 18). In a comprehensive retrospective study we managed to locate 8 patients who experienced recurrent intravaginal testicular torsion following previous fixation performed in our institute. RESULTS: The patients who experienced repeat torsion have initially presented at the mean age of 18.5 years old (range 12 to 30) with unilateral twisted testicle (left 3, right 5). Urgent explorations were generally performed, apart from in 2 cases that underwent spontaneous detorsion which was followed by an elective surgery. Testicular fixation was conducted by suturing of the tunica albuginea to the dartos layer by 2 sutures at each side, using chromic 3-zero in the 3 more early cases, followed by the usage of polyglactin 3-zero stitches in 4 subsequent cases and 3 sutures of polypropylene 4-zero for each testicle, thereafter, in the most recent case. The patients presented with repeat torsion, 0.5 to 23 years subsequently (average 7 years), involving either the ipsilateral testicle in 4 cases or the contralateral gonad in 4. CONCLUSIONS: Recurrent torsion following previous testicular fixation may appear many years following the primary procedure, even in cases in which either polyglactin or, notwithstanding, polypropylene sutures have been applied, in accordance with the common practice used in the last 2 decades. Increased awareness regarding this possibility is imperative for early diagnosis and prevention of testicular loss.

Adolescent↗

ErbB2 is a tumor associated antigen and a suitable therapeutic target in Wilms tumor.

PURPOSE: The modern multimodality therapeutic approach to Wilms tumor (WT), combining surgery with radiotherapy and chemotherapy results in high cure rates even for high stage disease. However, the combination of radiotherapy and chemotherapy is associated with severe early and late complications such as neutropenic sepsis, growth retardation and secondary malignancies. Therefore, novel therapeutic strategies, which would decrease the treatment burden, are required. We studied the expression of erbB2 growth factor receptor in WT cells as well as its role as a tumor therapeutic target in an in vivo xenograft model of Wilms tumor. MATERIALS AND METHODS: Paraffin embedded pathological samples from 14 different WT cases as well as xenografts derived thereof were immunostained with anti-erbB2 monoclonal antibody. The immunostaining was graded in comparison to a known positive control (breast cancer) and was scored by the intensity of staining (0 to +3) multiplied by the percentage of cells expressing the antigen. The expression of erbB2 in the human WT xenograft was verified also by fluorescence activated cell sorter analysis. In addition, nude mice bearing established subcutaneous human WT xenografts were treated with either 3 intraperitoneal injections of N29 anti-erbB2 monoclonal antibody or irrelevant antibody. RESULTS: All of the authentic human pathological samples, except 1 anaplastic WT as well the WT xenografts (at different stages), expressed erbB2. Expression was also observed in WT metastasis and in tumors which out grew chemotherapy. Systemic administration of anti-erbB2 monoclonal antibody inhibited and even prevented the growth of WT xenograft in vivo. CONCLUSIONS: ErbB2 is a tumor associated antigen in WT. Being expressed in almost all tumor stages, our in vivo model suggests that erbB2 may serve as a WT therapeutic target. Further work is needed to establish the role of erbB2 in the disease and its potential use in decreasing current treatment burden.

Adolescent↗

Lack of MHC expression and retention of ultrastructural characteristics by xenograft transmissible venereal tumor cells in SCID mice.

Canine transmissible venereal tumor (CTVT) is primarily a tumor of adult dogs with a high incidence of spontaneous regression. We recently reported a xenograft model of CTVT (XTVT) in NOD/SCID mice. XTVT cells retain cytological and histological features of CTVT as well as characteristic rearranged LINE/c-MYC junction [Am. J. Vet. Res. 62 (2001) 907]. In this paper, we demonstrate that XTVT cells maintain ultrastructural characteristics of CTVT and do not express MHC classes I and II molecules.

Animals↗

Use of a murine xenograft model for canine transmissible venereal tumor.

OBJECTIVE: To develop a murine model for canine transmissible venereal tumor (CTVT). ANIMALS: Thirty-three 6-week-old NOD/LtSz-scid (NOD/SCID) mice and seven 6-week-old C57BL/6J mice. PROCEDURE: Samples of CTVT were excised from a 3-year-old dog and inoculated SC into ten 6-week-old NOD/SCID mice to induce growth of xenograft transmissible venereal tumor (XTVT). To establish mouse-to-mouse transmission, samples of XTVT were removed and inoculated SC into 4 groups of 6-week-old NOD/SCID mice and into a control group. Samples of CTVT were also inoculated into immunocompetent C57BL/6J mice for a mouse antibody production (MAP) test. The canine and xenografted tumors were evaluated cytologically and histologically, and polymerase chain reaction was performed for detection of the rearranged LINE/c-MYC junction. RESULTS: 8 of 10 NOD/SCID mice that were inoculated with CTVT developed tumors 3 to 10 weeks after inoculation. In the second-generation xenograft, all mice developed tumors by postinoculation day 47; 1 X 10(6) of XTVT cells were enough to create a xenograft. Metastases developed in 4 of 20 mice. Xenografted and metastatic tumors retained cytologic, histologic, and molecular characteristics of CTVT. Results of the MAP test were negative for all pathogens. CONCLUSION: We established an NOD/SCID murine model for XTVT and metastasis of CTVT. This model should facilitate study of tumor transplantation, progression, and metastasis and should decrease or eliminate the need for maintaining allogenic transfer in dogs.

Animals↗

WISH-PC2: a unique xenograft model of human prostatic small cell carcinoma.

Prostatic small cell carcinoma is an aggressive subtype of prostate cancer that usually appears as a progression of the original adenocarcinoma. We describe here the WISH-PC2, a novel neuroendocrine xenograft of small cell carcinoma of the prostate. This xenograft was established from a poorly differentiated prostate adenocarcinoma and is serially transplanted in immune-compromised mice where it grows within the prostate, liver, and bone, inducing osteolytic lesions with foci of osteoblastic activity. It secretes to the mouse Chromogranin A and expresses prostate plasma carcinoma tumor antigen-1, six-transmembrane epithelial antigen of the prostate, and members of the Erb-B receptor family. It does not express prostate-specific antigen, prostate stem cell antigen, prostate-specific membrane antigen, and androgen receptor, and it grows independently of androgen. Altogether, WISH-PC2 provides an unlimited source in which to study the involvement of neuroendocrine cells in the progression of prostatic adenocarcinoma and can serve as a novel model for the testing of new therapeutic strategies for prostatic small cell carcinoma.

Adenocarcinoma↗

[Malignant lymphoma of the bladder].

Urinary tract lymphoma is usually reported when the secondarily stem is affected by widespread non-Hodgkin lymphoma. We describe an 83-year-old woman who presented with secondary lymphoma of the bladder 3 years after diagnosis when it initially infiltrated her breast. Treatment included local transurethral excision followed by chemotherapy, during which she died of disseminated disease.

Aged↗

[The Mitrofanoff pouch in lower urinary tract reconstruction].

The Mitrofanoff principle, first described in 1980, consists of implanting a tubular organ such as the appendix, ureter, or fallopian tube into the wall of the bladder (or urinary reservoir) to create a non-refluxing, catherizable urinary conduit. Between 1993-1996, 7 men and 1 woman (aged 48-64, average 59) underwent radical cystectomy and urethrectomy combined with the creation of a MAINZ I urinary reservoir (based on the Mitrofanoff principle). In men the indication for the procedure was the diagnosis of invasive transitional cell carcinoma of the bladder with involvement of the prostatic urethra. All patients had refused urinary diversion to an ileal conduit because of its deleterious effect on the quality of life. In all patients the postoperative course was uneventful, apart from intraperitoneal urinary leakage from the reservoir in 1, successfully managed conservatively. The patients have gained full control of urinary drainage, performing intermittent self-catheterizations every 4-5 hours. In 3 patients there were difficulties with catheterization due to stenosis of the conduit, usually at the skin level. None have suffered leakage from the reservoir, during the day, even when it was full. Our experience shows that creation of a continent urinary reservoir according to the MAINZ I technique is an excellent surgical solution for patients in whom the creation of an orthotopic reservoir is impractical. The use of the umbilicus as a stomal site preserves normal body image and thus does not interfere with quality of life as in those undergoing radical cystectomy.

Female↗

[Transrectal ultrasound-controlled needle aspiration of a prostatic cyst].

Prostatic cysts are common and are usually acquired and asymptomatic. Congenital prostatic cysts, which may originate from the wolffian system or from remnants of the Muellerian duct, are rare and may cause obstructive symptoms in young adults. Due to the availability of transrectal ultrasonography an increased number of cases of prostatic cysts are being diagnosed. We report a 36-year-old man with a congenital prostatic cyst which caused increasing pain during ejaculation and decreased the force of the urinary stream. It was diagnosed by ultrasonography and treated successfully by ultrasound-controlled, transrectal needle aspiration. There was immediate, complete disappearance of symptoms and no complications.

Adult↗