The pineal secretory product melatonin reportedly regulates release of growth hormone in humans and prevents phototherapy-induced hypocalcemia in newborn rats, suggesting that melatonin affects bone metabolism. Little is known about the effects of melatonin on bone in vitro or in vivo. The present study was undertaken to examine whether melatonin acts directly on normal human bone cells (HOB-M cells) and human osteoblastic cell line (SV-HFO cells) to affect osteogenic action in vitro. The effect of melatonin on bone cell proliferation was determined using the 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carbo xanilide (XTT) assay after a 24 hr incubation with melatonin. Melatonin significantly and dose-dependently increased the proliferation in HOB-M cells and SV-HFO cells by 215 +/- 22.1%, and 193 +/- 6.4%), respectively, with a maximal effect at a concentration of 50 microM. To evaluate the effect of melatonin on bone cell differentiation, alkaline phosphatase (ALP) activity, osteocalcin secretion and procollagen type I c-peptide (PICP) production (a measure of type I collagen synthesis) were measured after a 48 hr treatment. While melatonin at micromolar concentrations did not significantly affect either the ALP activity or the osteocalcin secretion, it significantly and dose-dependently increased the PICP production in HOB-M cells and SV-HFO cells by 983 +/- 42.2%, and 139 +/- 4.2%, respectively, with the maximal stimulatory doses between 50 and 100 microM. These results provide new evidence that melatonin stimulates the proliferation and type I collagen synthesis in human bone cells in vitro, suggesting that melatonin may act to stimulate bone formation.
Clinicopathologic characteristics and prognosis of breast cancer patients associated with pregnancy and lactation were clarified by means of a case‐control study of matched non‐pregnant and non‐lactating patients with breast cancer. From 18 institutions in Japan, a total of 192 subjects with breast cancer diagnosed during pregnancy (72 cases) and lactation (120 cases) were collected between 1970 and 1988, accounting for 0.76% of all breast cancer patients. The duration of symptoms was longer and tumor size was larger in the study subjects. Although the disease‐free interval was longer than that in the control patients, the survival time was shorter. There was no characteristic difference in histologic type. Vascular invasion and lymph node metastasis were found more frequently in the subjects. The positive rates of estrogen receptor and progesterone receptor were lower in the subjects. The 5‐ and 10‐year survival rates of the study patients were 65% and 55%, respectively, and these survivals were significantly lower than those of the control (P < 0.001). The survival rates were poorer in the subjects, in accordance with stage and lymph node metastasis. The results suggest that most of the patients with breast cancer diagnosed during pregnancy and lactation are in a more advanced stage because of a delay in detection and diagnosis, and hence have unfavorable prognosis. Therefore, it is important to diagnose and treat early for improvement of prognosis in patients with breast cancer during pregnancy and lactation.
Background. The development of a sensitive method for the detection of breast carcinoma micrometastases in axillary lymph nodes is reported.
Methods. The method was based on amplification of MUCl mRNA, which encodes a core protein of polymorphic epithelial mucin, by a reverse transcriptase‐polymerase chain reaction (RT‐PCR). Total RNA, which was extracted from a breast carcinoma cell line (MCF‐7), primary breast carcinomas, and axillary lymph nodes, was subjected to analysis of MUCl mRNA expression by the RT‐PCR method.
Results. MUCl mRNA expression was detected by RT‐PCR in MCF‐7 cells and in all 15 primary breast carcinomas but not in control lymph nodes taken from patients with benign diseases. A serial dilution study revealed that MUCl RT‐PCR was a very sensitive method, detecting one MCF‐7 cell per 1,000,000 lymph node cells.
The detection sensitivity of MUCl RT‐PCR method was compared with that of immunohistochemical staining of an epithelial marker (polymorphic epithelial mucin). Fifty axillary lymph nodes were obtained from 15 patients with primary breast carcinomas, and metastasis in each lymph node was investigated by both methods. The immunohistochemical method demonstrated metastasis in nine lymph nodes, and MUCl mRNA was detected in all of them. Of the 41 lymph nodes that were diagnosed to be devoid of metastasis by immunohistochemistry, MUCl mRNA was expressed by 6 but not by the other 35, indicating the presence of micrometastases in these 6 lymph nodes that could be detected only by the MUCl RT‐PCR method.
Conclusions. The MUCl RT‐PCR method is more sensitive than immunohistochemistry for the detection of micrometastases in axillary lymph nodes. This new method would be of practical value in selecting the patients at high risk for relapse from those who are histologically lymph node negative.
Intraoperative imprint cytology is a useful method for evaluating the status of sentinel nodes and is more accurate than frozen-section analysis. In addition, imprint cytology can detect micrometastasis more accurately than conventional haematoxylin and eosin-stained sectioning.
The effect of cyclophosphamide (CY) on ovarian function was studied in patients with breast cancer receiving prolonged daily administration of this agent (100 mg/day) after radical surgery. Out of 18 premenopausal patients that received 8.4-39.9 g CY, 15 developed permanent amenorrhea. The average dose given before the onset of amenorrhea was 5.2 g in patients in their 40s and 9.3 in their 30s. Urinary estrogens and serum progesterone were measured weekly for approximately 6 months postoperatively in six patients receiving CY. After the onset of amenorrhea, the levels of both hormones ceased to show their normal cyclic changes and remained low persistently, meanwhile serum FSH and LH were markedly elevated. No ovarian follicle was histologically found in three amenorrheic patients who underwent therapeutic oophorectomy after CY therapy. These findings indicate that CY induced primary ovarian failure.
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