Mechanism-based inhibition of CYP3A subfamilies by macrolide antibiotics and piperine.

OBJECTIVE: The mechanism-based inhibition of macrolide antibiotics, such as erythromycin and clarithromycin, and piperine on testosterone 6ß-hydroxylation activities by cytochrome P450 (CYP) 3A4, polymorphically expressed CYP3A5, and fetal CYP3A7 were compared. METHODS: 6ß-Hydroxy testosterone was determined by high-performance liquid chromatography. RESULTS: Although preincubation with erythromycin and clarithromycin decreased CYP3A4-meditaed testosterone 6ß- hydroxylation in a time-dependent manner, and the estimated maximum inactivation rate constant (k inact ) and the inactivation rate constant reaching half of k inact (K i ) for erythromycin were approximately 1/2 and 1/5, respectively, of those for clarithromycin. Obvious preincubation time-dependent inhibition of erythromycin against CYP3A5 and CYP3A7 was not observed. Piperine exhibited preincubation time- dependent inhibition, and the calculated K i and k inact values for CYP3A4 were approximately 1/7 and 1/2, respectively, of those for CYP3A5. CONCLUSION: It is speculated that the preincubation-dependent inhibition by piperine would be more potent in CYP3A5 non-expressors than CYP3A5-expressors.

Comparison of the Stimulatory and Inhibitory Effects of Steroid Hormones and α-Naphthoflavone on Steroid Hormone Hydroxylation Catalyzed by Human Cytochrome P450 3A Subfamilies.

The inhibitory and stimulatory effects of steroid hormones and related compounds on the hydroxylation activity at the 6ß-position of two steroid hormones, progesterone and testosterone, by CYP3A4, polymorphically expressed CYP3A5, and fetal CYP3A7 were compared to clarify the catalytic properties of the predominant forms of the human CYP3A subfamily. Hydroxylation activities of progesterone and testosterone by CYP3A4, CYP3A5, and CYP3A7 were estimated using HPLC. The Michaelis constants (Km) for progesterone 6ß-hydroxylation by CYP3A5 were markedly decreased in the presence of dehydroepiandrosterone (DHEA) and α-naphthoflavone (ANF), whereas progesterone and DHEA competitively inhibited testosterone 6ß-hydroxylation mediated by CYP3A4, and progesterone competitively inhibited CYP3A5-mediated activity, which was weaker than that for CYP3A4. ANF noncompetitively inhibited testosterone 6ß-hydroxylation mediated by both CYP3A4 and CYP3A5. Progesterone and testosterone 6ß-hydroxylation mediated by CYP3A7 was inhibited or unaffected by DHEA, pregnenolone, and ANF. These results suggested that DHEA and ANF stimulated progesterone 6ß-hydroxylation by CYP3A5 but not by CYP3A4 and CYP3A7; however, progesterone, DHEA, and ANF inhibited testosterone 6ß-hydroxylation mediated by all CYP3A subfamily members. The inhibitory/stimulatory pattern of steroid-steroid interactions is different among CYP3A subfamily members and CYP3A5 is the most sensitive in terms of activation among the CYP3A subfamily members investigated.

Relationship between detection of the cervical gland area during the late third trimester and necessity for induction of labor to prevent post-term delivery.

OBJECTIVES: With the maturation of the cervical canal during pregnancy, the cervical gland area (CGA) as observed on transvaginal ultrasonography is gradually obscured. The aim of this study was to elucidate the significance of CGA in the late third trimester as a determinant of the outcome of labor. METHODS: We investigated 123 primiparous women with singleton pregnancies at 36-41 weeks' gestation. The women were divided into two groups: a normal delivery group (93 women), which had vaginal delivery without medical intervention, and an induction of labor group (30 women), which required induction of labor after 41 weeks and 0 day. At outpatient prenatal checkups, the Bishop score (BS) was assessed by pelvic examination, and cervical length (CL) and CGA were evaluated by transvaginal ultrasonography. The relationship between each parameter and induction of labor was retrospectively determined and compared. RESULTS: Time-dependent assessment of each outcome determinant showed that the CGA detection rate was higher and the CL was longer in the induction of labor group from 3 weeks to 1 week before delivery at a significant level (P < 0.05); however, the BS was significantly lower in the induction of labor group only at 1 week before delivery (P < 0.05). When multiple logistic regression analysis of the necessity of induction of labor was conducted using BS, CL, and CGA parameters as explanatory variables at 1 week before delivery, CGA alone was shown to be an independent predictor of induction of labor (OR = 6.1, 95 % CI 2.3-16.2). CONCLUSION: The present study suggests that in the late third trimester, evaluation of CGA with transvaginal ultrasonography is most useful in predicting the necessity of induction of labor to prevent post-term delivery.

Human epidermal growth factor receptor-2 overexpression and amplification in metastatic and recurrent high grade or type 2 endometrial carcinomas.

INTRODUCTION: Human epidermal growth factor receptor (HER)-2 overexpression or gene amplification is more common in high-grade or type 2 endometrial carcinomas. We assessed the discordance of HER-2 expression between primary and metastatic or recurrent endometrial carcinomas. MATERIALS AND METHODS: Thirty-six primary, along with 14 metastatic and five recurrent tumors (matched to primaries), pathologically confirmed as high-grade or type 2 endometrial carcinomas, were submitted for immunohistochemistry (IHC) for HER-2. Fluorescence in situ hybridization was performed when the tumors showed HER-2 overexpression (≥2+ IHC score). The results of the IHC and fluorescence in situ hybridization assays were compared between the primary and metastatic or recurrent tumors. The relationships between HER-2 expression and clinicopathological factors or prognosis were investigated. RESULTS: HER-2 overexpression and HER-2 amplification (a ratio of HER-2 copies to chromosome 17 [CEP17] copies ≥2.2) were detected in 33.3% (twelve of 36 patients) and 5.6% (two of 36 patients) of primary tumors, respectively. HER-2 overexpression was not associated with clinicopathological factors or prognosis. In 19 tumor specimens obtained from metastatic or recurrent tumors, HER-2 overexpression and HER-2 amplification were detected in 57.9% (eleven patients) and 15.8% (three patients), respectively. HER-2 overexpression tended to predict a worse prognosis. CONCLUSION: HER-2 expression in metastatic or recurrent tumors was more frequent than in matched primary high-grade or type 2 endometrial carcinomas. Trastuzumab in combination with cytotoxic chemotherapy may represent an alternative therapeutic option for these tumors.

A case of primary alveolar soft part sarcoma of the uterine cervix and a review of the literature.

Alveolar soft part sarcoma (ASPS) that originates from the uterine cervix is extremely rare, with only thirteen cases reported. The participation of the ASPL-TFE3 chimeric gene, translocation (X; 17) (p11; q25), has been demonstrated in ASPS. Here, we report a case of cervical ASPS, along with a review of the literature. The patient, a 56-year-old woman, was referred for a 70 × 80 mm cervical tumor. She underwent a hysterectomy and bilateral salpingo-oophorectomy, and remained disease free for 66 months without adjuvant therapy. Pathological examination revealed features consistent with ASPS. In addition, the present case demonstrated strong positive nuclear staining for TFE3, and ASPL-TFE3 fusion gene type 1 was detected by RT-PCR. In a review of fourteen cases of this tumor (including the present case), the immunohistochemical expression patterns of myogenic or neuroendocrine markers were somewhat varied among cases. In all cases except for the present case, the patients were under 40 years of age, and the tumor sizes were under 5 cm. The prognosis of ASPS in the cervix was considerably better than that of ASPS in soft tissues. Complete resection with adequate margins is thought to be important, although the appropriate surgical method, including lymph node dissection, is uncertain. The role of chemotherapy or radiotherapy as adjuvant therapy has not been defined. Cervical ASPS is extremely rare, making case series the most viable option for understanding their natural history and for developing a treatment strategy, including an optimal surgical procedure and adjuvant therapy.

Effects of a selective COX-2 inhibitor in patients with uterine endometrial cancers.

PURPOSE: COX-2 is highly expressed in endometrial cancers, suggesting that a selective COX-2 inhibitor could be valuable for treating endometrial cancers that overexpress COX-2. In this study, we investigated the anti-tumor effects of the selective COX-2 inhibitor etodolac on endometrial cancer patients. METHODS: Etodolac (400 mg, bid, for 2 weeks) was administered preoperatively to 21 endometrial cancer patients who had provided informed consent. Using pre-treatment biopsies and post-treatment surgical specimens, the expression levels of COX-2, Ki-67, p53, p21, p27, and cyclin D1 were evaluated by immunohistochemistry and the apoptotic index (AI) was determined by TUNEL staining. Preoperative biopsies and surgical specimens from 32 patients with endometrial cancer not treated with etodolac served as controls. RESULTS: Surgical specimens from COX-2 positive endometrial cancer patients treated with etodolac had significantly reduced expression levels of COX-2, Ki-67, p53, p21, p27, and cyclin D1 as determined by immunohistochemistry, while AI was not affected. These markers were unchanged for COX-2 negative endometrial cancer patients treated with etodolac and the control group. CONCLUSIONS: The selective COX-2 inhibitor etodolac showed anti-proliferative effects by suppressing COX-2 and cell-cycle regulator protein expression in patients with endometrial cancer positive for COX-2 expression. This study demonstrates that a selective COX-2 inhibitor is a potentially beneficial treatment for COX-2 positive endometrial cancers.