Electrostatic control of structure in self-assembled membranes

Self-assembling peptide amphiphiles (PAs) can form hierarchically ordered membranes when brought in contact with aqueous polyelectrolytes of the opposite charge by rapidly creating a diffusion barrier composed of filamentous nanostructures parallel to the plane of the incipient membrane. Following this event, osmotic forces and charge complexation template nanofiber growth perpendicular to the plane of the membrane in a dynamic self-assembly process. In this work, we show that this hierarchical structure requires massive interfacial aggregation of PA molecules, suggesting the importance of rapid diffusion barrier formation. Strong PA aggregation is induced here through the use of heparin-binding PAs with heparin and also with polyelectrolytes of varying charge density. Small angle X-ray scattering shows that in the case of weak PA-polyelectrolyte interaction, membranes formed display a cubic phase ordering on the nanoscale that likely results from clusters of PA nanostructures surrounded by polyelectrolyte chains.

A designer peptide as a template for growing Au nanoclusters

A peptide was designed to generate a sub-nanometric template that guides the growth of fluorescent gold nanoclusters.

LMTK3 is implicated in endocrine resistance via multiple signaling pathways

Resistance to endocrine therapy in breast cancer is common. With the aim of discovering new molecular targets for breast cancer therapy, we have recently identified LMTK3 as a regulator of the estrogen receptor-alpha (ERα) and wished to understand its role in endocrine resistance. We find that inhibition of LMTK3 in a xenograft tamoxifen (Tam)-resistant (BT474) breast cancer mouse model results in re-sensitization to Tam as demonstrated by a reduction in tumor volume. A whole genome microarray analysis, using a BT474 cell line, reveals genes significantly modulated (positively or negatively) after LMTK3 silencing, including some that are known to be implicated in Tam resistance, notably c-MYC, HSPB8 and SIAH2. We show that LMTK3 is able to increase the levels of HSPB8 at a transcriptional and translational level thereby protecting MCF7 cells from Tam-induced cell death, by reducing autophagy. Finally, high LMTK3 levels at baseline in tumors are predictive for endocrine resistance; therapy does not lead to alteration in levels, whereas in patient's plasma samples, acquired LMTK3 gene amplification (copy number variation) was associated with relapse while receiving Tam. In aggregate, these data support a role for LMTK3 in both innate (intrinsic) and acquired (adaptive) endocrine resistance in breast cancer.

A bioactive self-assembled membrane to promote angiogenesis

We report here on a bioactive hierarchically structured membrane formed by self-assembly. The membrane is formed with hyaluronic acid and peptide amphiphiles with binding affinity for heparin, and its hierarchical structure contains both an amorphous zone and a layer of fibrils oriented perpendicular to the membrane plane. The design of bioactivity is based on the potential ability to bind and slowly release heparin-binding growth factors. Human mesenchymal stem cells (hMSCs) seeded on these membranes attached and remained viable. Basic fibroblast growth factor (FGF2) and vascular endothelial growth factor (VEGF) were incorporated within the membrane structure prior to self-assembly and released into media over a prolonged period of time (14 days). Using the chicken chorioallantoic membrane (CAM) assay, we also found that these membranes induced a significant and rapid enhancement of angiogenesis relative to controls.

Self-assembling nanostructures to deliver angiogenic factors to pancreatic islets

Supramolecular self-assembly of nanoscale filaments offers a vehicle to signal cells within dense cell aggregates such as pancreatic islets. We previously developed a heparin-binding peptide amphiphile (HBPA) that self-assembles into nanofiber gels at concentrations of 1% by weight when mixed with heparin and activates heparin-binding, angiogenic growth factors. We report here on the use of these molecules at concentrations 100 times lower to drive delivery of the nanofibers into the dense islet interior. Using fluorescent markers, HBPA molecules, heparin, and FGF2 were shown to be present in and on the surface of murine islets. The intraislet nanofibers were found to be necessary to retain FGF2 within the islet for 48 h and to increase cell viability significantly for at least 7 days in culture. Furthermore, enhanced insulin secretion was observed with the nanofibers for 3 days in culture. Delivery of FGF2 and VEGF in conjunction with the HBPA/heparin nanofibers also induced a significant amount of islet endothelial cell sprouting from the islets into a peptide amphiphile 3-D matrix. We believe the infiltration of bioactive nanofibers in the interior of islets as an artificial ECM can improve cell viability and function in vitro and enhance their vascularization in the presence of growth factors such as FGF2 and VEGF. The approach described here may have significant impact on islet transplantation to treat type 1 diabetes.

Nitric oxide and nanotechnology: a novel approach to inhibit neointimal hyperplasia

OBJECTIVE

Nitric oxide (NO) has been shown to inhibit neointimal hyperplasia after arterial interventions in several animal models. To date, however, NO-based therapies have not been used in the clinical arena. Our objective was to combine nanofiber delivery vehicles with NO chemistry to create a novel, more potent NO-releasing therapy that can be used clinically. Thus, the aim of this study was to evaluate the perivascular application of spontaneously self-assembling NO-releasing nanofiber gels. Our hypothesis was that this application would prevent neointimal hyperplasia.

METHODS

Gels consisted of a peptide amphiphile, heparin, and a diazeniumdiolate NO donor (1-[N-(3-Aminopropyl)-N-(3-ammoniopropyl)]diazen-1-ium-1,2-diolate [DPTA/NO] or disodium 1-[(2-Carboxylato)pyrrolidin-1-yl]diazen-1-ium-1,2-diolate [PROLI/NO]). Nitric oxide release from the gels was evaluated by the Griess reaction, and scanning electron microscopy confirmed nanofiber formation. Vascular smooth muscle cell (VSMC) proliferation and cell death were assessed in vitro by (3)H-thymidine incorporation and Personal Cell Analysis (PCA) system (Guava Technologies, Hayward, Calif). For the in vivo work, gels were modified by reducing the free-water content. Neointimal hyperplasia after periadventitial gel application was evaluated using the rat carotid artery injury model at 14 days (n = 6 per group). Inflammation and proliferation were examined in vivo with immunofluorescent staining against CD45, ED1, and Ki67 at 3 days (n = 2 per group), and graded by blinded observers. Endothelialization was assessed by Evans blue injection at 7 days (n = 3 per group).

RESULTS

Both DPTA/NO and PROLI/NO, combined with the peptide amphiphile and heparin, formed nanofiber gels and released NO for 4 days. In vitro, DPTA/NO inhibited VSMC proliferation and induced cell death to a greater extent than PROLI/NO. However, the DPTA/NO nanofiber gel only reduced neointimal hyperplasia by 45% (intima/media [I/M] area ratio, 0.45 +/- 0.07), whereas the PROLI/NO nanofiber gel reduced neointimal hyperplasia by 77% (I/M area ratio, 0.19 +/- 0.03, P < .05) vs control (injury alone I/M area ratio, 0.83 +/- 0.07; P < .05). Both DPTA/NO and PROLI/NO nanofiber gels significantly inhibited proliferation in vivo (1.06 +/- 0.30 and 0.19 +/- 0.11 vs injury alone, 2.02 +/- 0.20, P < .05), yet had minimal effect on apoptosis. Only the PROLI/NO nanofiber gel inhibited inflammation (monocytes and leukocytes). Both NO-releasing nanofiber gels stimulated re-endothelialization.

CONCLUSIONS

Perivascular application of NO-releasing self-assembling nanofiber gels is an effective and simple therapy to prevent neointimal hyperplasia after arterial injury. Our study demonstrates that the PROLI/NO nanofiber gel most effectively prevented neointimal hyperplasia and resulted in less inflammation than the DPTA/NO nanofiber gel. This therapy has great clinical potential to prevent neointimal hyperplasia after open vascular interventions in patients.

Effects of a herbal compound containing bupleurum on human lymphocytes

Bupleurum-containing compounds, such as KY88 Liver Livo are thought to have immunomodulatory effects. This study investigated the effects of KY88 Liver Livo on the mitogenic induction of lymphocytes in vitro. Fifteen healthy human adult volunteers, aged between 20 and 50 years, provided peripheral blood samples from which lymphocytes were obtained by Ficoll-Hypaque centrifugation. The separated lymphocytes were stimulated by phytohaemagglutinin and KY88 Liver Livo in varying concentrations for 72 hours, with greater cluster and colony formation evident compared with lymphocytes in a control preparation. KY88 Liver Livo was also found to induce the secretion of granulocyte-macrophage colony-stimulating factor in a dose-dependent fashion. These preliminary in vitro studies suggest that KY88 Liver Livo may have potential clinical value in the treatment of chronic viral infection and in the management of immunocompromised patients.

Neoadjuvant chemotherapy for Chinese women with locally advanced breast cancer

Locally advanced breast cancer carries a poor prognosis and is still prevalent in developing countries. The current management usually involves administration of neoadjuvant chemotherapy (NCT). From March 1990 through December 1997, 173 Chinese patients with tumor size greater than 4 cm were treated; 38 received NCT and the other 135 postoperative adjuvant chemotherapy. The regimens for NCT were FEC (5-fluorouracil 600 mg/m2, epirubicin 50 mg/m2, and cyclophosphamide 600 mg/m2) for 29 patients and Adriamycin 75 mg/m2 for the rest of the group. Postoperatively the NCT patients received the standard CMF regimen (oral cyclophosphamide 100 mg/m2 for 14 days and intravenous methotrexate 40 mg/m2 and 5-fluorouracil 600 mg/m2 on days one and eight of each cycle). The postoperative adjuvant chemotherapy group received only the CMF regimen. Tumor response after NCT was measured clinically and histologically. The response rate was 75 per cent with 13.2 per cent being complete response. Although there is no difference in response rate the actual reduction in size was greater for patients receiving Adriamycin than FEC (P = 0.001). The only predictive factor of response to NCT was the type of chemotherapy administered. None of the tumor characteristics such as size, nodal status, histological grading, lymphovascular permeation, hormonal receptor status, and c-erb-B2 expression were found to be significant. The overall 5-year probability of survival was 0.44, and there was no difference between groups. The factor important for prognosis was axillary nodal status on histology. The use of NCT did not improve outcome. In summary our results showed that NCT was feasible for Chinese women and good response could be achieved. However, it is the axillary nodal status that determines the final outcome.

The use of focus group interviews in Asian medical education evaluative research

OBJECTIVE

To evaluate the use of focus group interviews in Asian medical education evaluative research.

METHODS

Randomly selected medical students were invited to participate in 30 focus group interviews to provide in-depth data about the effect on their learning of the introduction of early clinical skills. Efforts were made to meet all the students to help them understand the objectives of the focus group. Confidentiality was emphasised and a non-faculty interviewer was recruited for the interviews.

RESULTS

The students considered the use of focus groups to be a more meaningful way of collecting students' opinions than other methods, for example structured questionnaire, because it allowed an interactive discussion. They also felt that having an independent non-faculty interview moderator had encouraged them to express their opinions more candidly during the interviews.

CONCLUSION

The use of focus group interviews among Asian medical students for evaluative research is practical and efficient.

Detection of circulating breast cancer cells with multiple-marker RT-PCR assay

RT-PCR assay for multiple markers has been shown to increase the detection rate of circulating tumor cells. This assay targeted against cytokeratin 19 (CK19), cytokeratin 20 (CK20) and beta-subunit of human chorionic gonadotropin (beta-hCG) was used to detect circulating breast cancer cells. 5 ml of peripheral blood was drawn before any surgical procedures from 72 breast cancer patients and 30 cases with benign breast disease. Total RNA was extracted from peripheral blood mononuclear cells, reverse-transcripted and amplified. For the benign cases, 10% (3/30) were positive for CK19 and all were negative for CK20 and beta-hCG, whereas 9.72% (7/72), 2.78% (2/72) and 12.5% (9/72) of the malignant cases were positive for CK19, CK20 and beta-hCG respectively. The detection rate of circulating breast cancer cells was unchanged when CK19 was combined with CK20, but it increased to 18.1% (13/72) when the marker was combined with beta-hCG. A significant difference was observed for beta-hCG between benign cases and affected patients with stage II, III and IV disease (p = 0.026). In conclusion, positive RT-PCR signals in blood samples of affected patients correlated with stage, in particular for beta-hCG. CK19/beta-hCG was a promising marker combination.

Practice of breast self-examination among high risk Chinese women in Hong Kong

BACKGROUND

The incidence of breast cancer in Hong Kong is increasing and breast self-examination (BSE) as a screening tool is becoming more popular, especially among first-degree relatives (FDR) of breast cancer victims. BSE may be more applicable to Chinese women as their breast size is smaller. This study explores the BSE practice in this group of women.

METHODS

A cross sectional study was conducted by sending questionnaires to 330 FDR of breast cancer patients treated in the Department of Surgery, University of Hong Kong. BSE behavior was studied with respect to its frequency, awareness, completeness and confidence of practice.

RESULTS

110 subjects returned the questionnaires with a response rate of 33%. The mean age of the respondent was 37 years. Only 57 women (52%) were practicers. The practicers have a stronger BSE awareness (P < 0.01) and a lower mean score on thought barriers (P = 0.002) than the non-practicers. 40% of the practicers gain their BSE knowledge through clinicians and their mean period of practice was 3.2 years. 68% of the practicers performed BSE completely. The overall confidence rate was 35%, but the rate was 43% among those who performed complete BSE. Thirteen factors possibly related to the completeness and rate of confidence of BSE examination were studied. The only factor that significantly determined completeness was the time spent for each examination (P = 0.002). The complete practicers required a longer time than the incomplete practicers (6.60 and 2.96 min, respectively). Women with a stronger BSE intention (P = 0.001) and a lower mean score on thought barriers (P = 0.001) performed the examination confidently.

CONCLUSIONS

Slightly over half of the FDR practice BSE. The majority perform a complete BSE but they are not confident in finding abnormalities. Women spending more time on BSE are associated with a higher rate of completeness. However, only those with a stronger BSE intention and lesser thought barriers are more confident in their practice.

Hormonal receptor determination of 1,052 Chinese breast cancers

BACKGROUND AND OBJECTIVES

Hormonal receptors are important prognostic factors for breast cancer. The reported figures in the literature are mostly on Caucasians. This study analyzes the receptor profile of 1,052 Chinese patients.

METHODS

The age of the patients ranged from 20-93 years; 48% were premenopausal and 52% postmenopausal. Estrogen receptor (ER) and progesterone receptor (PgR) were measured quantitatively by enzyme immunoassay (EIA) using the rat monoclonal antibody (ABBOTT ER-EIA). Specimens with values >15 fmol/mg were considered positive according to manufacturer's recommendation.

RESULTS

ER was positive in 53% and 61.6% of the pre- and postmenopausal women respectively (P < 0.0075); PgR was positive in 51.5% and 46.2% respectively (P > 0.05). The mean values of ER were higher for postmenopausal women (P < 0.0001) but the values for PgR were similar between the two groups (P > 0.05). When the values were analyzed with respect to age, there was an increasing trend for ER. No such trend was noted for PgR. Subgroup analysis showed that there were more ER+PgR+ tumors among postmenopausal than among premenopausal women. Tumors with dubious receptor status (ER+PgR- or ER-PgR+) were more prevalent at perimenopausal age.

CONCLUSIONS

Chinese patients have lower receptor values and positivity rates than those reported for Caucasians. Receptor-positive tumors tend to occur in postmenopausal women.

Clarithromycin attenuates mastectomy-induced acute inflammatory response

Based on the observation that administration of clarithromycin led to an attenuation of the inflammatory response induced by surgical trauma in a guinea pig model, we investigated the potential beneficial effects of clarithromycin on the local and systemic inflammatory response in patients undergoing mastectomy in an open-label prospective study. During a 16-month period, 54 patients who underwent mastectomy were randomly divided into two groups. In one group, the patients received oral clarithromycin at a dose of 500 mg twice a day, from the day before to 3 days after mastectomy. There was no significant difference in the incidence of antibiotic prophylaxis-related toxicities or postoperative infections between the patients who received clarithromycin and those who did not. Clarithromycin treatment was significantly associated with an attenuation of febrile response, tachycardia, tachypnea, and an increase in monocyte counts (P, <0.0001, <0.01, <0.05, and <0.01, respectively). Clarithromycin also reduced the intensity and duration of postoperative pain (P, <0.05 and <0.005, respectively) and increased the range of motion of the involved shoulder (P < 0.05 for abduction and flexion). We conclude that clarithromycin effectively modulates the acute inflammatory response associated with mastectomy and produces a better clinical outcome.

Fine needle aspiration may shed breast cells into peripheral blood as determined by RT-PCR

OBJECTIVE

A diagnostic test applying reverse-transcriptase chain reaction (RT-PCR) assay targeted against cytokeratin 19 (CK19), cytokeratin 20 (CK20) and the beta-subunit of human chorionic gonadotropin (beta-hCG) mRNAs was used to evaluate the impact of fine needle aspiration (FNA) on breast cell shedding into peripheral blood.

METHODS

The sensitivity of this assay was based on the different degree of admix of MCF-7 breast cancer cell line with HL-60 leukemic cell line. For blood samples of 24 cases with benign breast diseases and 20 cases with malignant ones, 5 ml of peripheral blood was drawn before and within 10 min after puncture. Total RNA was extracted from peripheral blood mononuclear (PBMN) cells; beta-actin was used to assess the quality of cDNA. RT-PCR products were run in ethidium bromide gel and observed under ultraviolet. RT-PCR products for beta-hCG were digested with Sty I endonuclease to confirm the specificity.

RESULTS

The sensitivity of RT-PCR assay was 1 MCF-7 cell in 10(5) HL-60 cells for CK19 and CK20, and 1 in 10(6) for beta-hCG. For 24 benign cases, none of the pre- FNA samples was positive for CK20 and beta-hCG, and 3 cases (12.5%) were positive for CK19. As for 20 malignant cases, 1 pre-FNA sample was positive for all three markers and 2 other samples were positive for CK19. After aspiration, 3/21 benign cases and 1/17 malignant case with pre-FNA negative signals became positive for CK19, while 3/19 malignant cases with pre-FNA negative signals were converted to a positive result for CK20 and beta-hCG. Of 6 pre-FNA positive cases, all cases remained positive for the respective marker.

CONCLUSION

FNA to breast tumor may cause hematogenous dissemination of breast cells.

Detection of circulating breast cancer cells by reverse transcriptase polymerase chain reaction (RT-PCR)

The confounding problem in treatment of breast cancer is the metastasis of breast tumour. Reverse transcriptase polymerase chain reaction (RT-PCR) has been recently used in the detection of circulating breast cancer cells. This review reports on the development of this assay as well as its advantages and disadvantages. We feel that cytokeratin 20 and beta -human chorionic gonadotropin (hCG) mRNA are the best markers for the detection of circulating breast cancer cells. We suggest that the multiple RNA marker RT-PCR assay can help to increase both sensitivity and specificity of detection, and that quantitative RT-PCR assay is more effective than the qualitative assay in the detection of circulating breast cancer cells.

Comparison of tamoxifen with danazol in the management of idiopathic gynecomastia

Idiopathic gynecomastia, unilateral or bilateral, is a common physical finding in normal men. Successful treatment using tamoxifen (antiestrogen) and danazol (antiandrogen) has recently been reported. We compared the efficacy of tamoxifen and danazol in the treatment of idiopathic gynecomastia. We reviewed the clinical records of patients with idiopathic gynecomastia presenting to the Department of Surgery, University of Hong Kong, between August 1990 and September 1995. Medical treatment with either tamoxifen (20 mg/d) or danazol (400 mg/d) was offered and continued until a static response was achieved. The treatment response was compared. Sixty-eight patients with idiopathic gynecomastia were seen in the Breast Clinic. The median age was 39.5 years (range, 13-82), with a median duration of symptoms of 3 months (range, 1-90). The median size was 3 cm (range, 1-7). Twenty-three patients were treated with tamoxifen and 20 with danazol. Complete resolution of the gynecomastia was recorded in 18 patients (78.2%) treated with tamoxifen, whereas only 8 patients (40%) in the danazol group had complete resolution. Five patients, all from the tamoxifen group, developed recurrence of breast mass. In conclusion, hormonal manipulation is effective in the treatment of patients with idiopathic gynecomastia. Although the effect is more marked for tamoxifen compared with danazol, the relapse rate is higher for tamoxifen. Further prospective randomized studies would be useful in defining the role of these drugs in the management of patients with idiopathic gynecomastia.

Somatic mutations in the BRCA1 gene in Chinese sporadic breast and ovarian cancer

Inherited mutations in the BRCA1 gene confer increased susceptibility to breast and ovarian cancer. Its role in sporadic carcinogenesis is not well defined. Somatic mutations in breast cancers have not been reported and to date there are only three reports of somatic mutations in sporadic ovarian cancers. To investigate the contribution of BRCA1 mutations to sporadic breast and ovarian cancer in the Chinese population, we analysed 62 samples from Chinese women using the protein truncation test. There were 40 cases of breast cancer under age 50 and 22 cases of ovarian cancer, all unselected for family history. There was no age selection for the ovarian cancers. We found two somatic BRCA1 mutations in exon 11, one in a breast cancer and the other in an ovarian cancer, both of which result in truncated proteins. Our results indicate that somatic BRCA1 mutations, like somatic mutations in the BRCA2 gene, though very rare, can be found in both breast and ovarian cancers and support a tumor suppressor function for BRCA1 in sporadic tumors.

Clarithromycin attenuates the inflammatory response induced by surgical trauma in a guinea pig model

The effect of clarithromycin on the systemic and local inflammatory responses after surgical trauma was investigated using a guinea pig model. There was no statistically significant difference in the body temperature and respiratory rate of the guinea pigs between the clarithromycin and control groups, although there was a trend towards a lower temperature in the first 36 h after the operation, and a trend towards a lower respiratory rate on day 1 and day 2 (P=0.07 and 0.18, respectively) in the clarithromycin group. The total leukocyte count of both groups of animals increased from day -1 to day 4, and the increase was more marked in the control group (P=0.06 on day 1). The neutrophil and monocyte counts of the two groups of animals also increased after the operation. The neutrophil count of the control group was significantly higher than the clarithromycin group on day 1 and 2 (P<0.05 and 0.01, respectively), and the monocyte count of the control group was significantly higher than the clarithromycin group on day 1 (P<0.005). Moreover, the platelet count of the animals also increased after the operation, and the count in the control group was significantly higher than the clarithromycin group on day 1, 2 and 4 (P<0.05, 0.005 and 0.005, respectively). There was no difference between the haemoglobin concentration, lymphocyte count, eosinophil count and basophil count between the two groups of animals. The number of animals with wound discharge was lower in the clarithromycin group than the control group throughout the post-operative period, but the difference was not statistically significant. None of the animals developed signs of wound infection. The present observation suggests that clarithromycin suppressed both the systemic and local inflammatory response after surgical trauma, and it prompts further animal experiments for delineation of the mechanism of action, as well as clinical trials in major surgical procedures.

Amplification of GAA/TTC triplet repeat in vitro: preferential expansion of (TTC)n strand

Several human hereditary neuromuscular and neurodegenerative diseases are caused by abnormal expansion of triplet repeat sequences (TRSs) CAG/CTG, CGG/CCG, or GAA/TTC on certain chromosomes. It is generally accepted that multiple slippage synthesis accounts for the instabilities of TRS. Earlier in vitro experiments by Behn-Krappa and Doerfler showed that TRS with high GC content can be expanded. In contrast, here we demonstrated that certain AT-rich TRSs, (TTC)17, (GAA)10/(TTC)10 and (GAA)17/(TTC)17, were also expansion-prone in PCR. With respect to the sequence of TRS, surprisingly, we found that the AT-rich (GAA)17/(TTC)17 extended more efficiently than the GC-rich (CAG)17/(CTG)17. This strongly suggested that the AT content of the repeat may influence TRS expansion. Furthermore, to examine the expansion of single-stranded TRS, we showed that only (TTC)17, but not the complementary (GAA)17, can be expanded. This suggested that a T-T mismatch may stabilize compatible secondary structures, most likely hairpins, for slippage synthesis. However, another poly-pyrimidine TRS, (CCT)17, is not amplification-prone in PCR. Due to the high C-content, this TRS is unlikely to adopt hairpin structures at the high pH used for PCR. Thus, the single-stranded PCR experiment may serve as an indirect assay for the ability of a sequence to adopt a hairpin conformation. When amplification was performed in reactions using Klenow DNA polymerase, only the double-stranded TRSs can be expanded. The reaction rate for (GAA)10/(TTC)10 was slower than for (GAA)17/(TTC)17, suggesting that the length of the repeat may be important for the amplification of TRS. The findings of these in vitro experiments may aid in understanding TRS expansion in vivo.

Comparison of antiemetic efficacy of granisetron and ondansetron in Oriental patients: a randomized crossover study

A double-blind randomized crossover trial was performed to compare the antiemetic efficacy of two 5-HT3 receptor antagonists, granisetron and ondansetron, in Chinese patients receiving adjuvant chemotherapy (cyclophosphamide, methotrexate and 5-fluorouracil) for breast cancer. Twenty patients were randomized to receive chemotherapy with either granisetron on day 1 and ondansetron on day 8 of the first cycle followed by the reverse order in the second cycle, or vice versa. The number of vomiting episodes and the severity of nausea in the first 24 h (acute vomiting/nausea) and the following 7 days (delayed vomiting/nausea) were studied. Acute vomiting was completely prevented in 29 (72.5%) cycles with granisetron and 27 (67.5%) cycles with ondansetron, and treatment failure (>5 vomiting episodes) occurred in two (5%) cycles with each agent (P = NS). Acute nausea was completely controlled in 15 (37.5%) cycles with granisetron and 14 (35%) cycles with ondansetron, whereas severe acute nausea occurred in four (10%) cycles with each agent (P = NS). However, complete response for delayed vomiting was observed in only 21 (52.5%) cycles with granisetron and 22 (55%) cycles with ondansetron (P = NS), and delayed nausea was completely controlled in only 11 (27.5%) and ten (25%) cycles respectively (P = NS). In conclusion, both granisetron and ondansetron are effective in controlling acute nausea and vomiting in Chinese patients, with equivalent antiemetic efficacy. Control of delayed nausea and vomiting is less satisfactory.

Risk factors for rebleeding and death from peptic ulcer in the very elderly

BACKGROUND

Ageing populations are increasing in many countries and bleeding peptic ulcers in patients older than 60 years carry a greater risk of rebleeding and death. This study aimed to identify the risk factors for rebleeding and death in very elderly patients with peptic ulcer bleeding. The efficacy of treatment in preventing recurrent bleeding and death in this group of patients was also studied by means of prospective data collection and analysis.

METHODS

Data relating to 1744 patients treated between September 1985 and January 1994 for peptic ulcer bleeding were collected prospectively and analysed. Patients were stratified by age to one of three groups: group 1 (less than 60 years, n = 833), group 2 (60-79 years, n = 706) and group 3 (80 or more years, n = 205).

RESULTS

Univariate and multivariate analyses of 21 factors possibly affecting either rebleeding or death identified age greater than 80 years as one of the factors significantly affecting rebleeding and death. In a comparison of groups 1, 2 and 3, the likelihood of rebleeding and death was significantly greater in group 3. Univariate and multivariate analyses for rebleeding and death were performed for each group. The severity of initial bleeding had a marked bearing on subsequent rebleeding rates for all three groups. In group 3, however, large ulcer size and impaired liver function were additional factors which correlated significantly with final outcome. No rebleeding or morbidity occurred when endoscopic treatment was performed early for patients in group 3 but there was a significantly greater risk of further recurrent haemorrhage and treatment-related morbidity when treatment was performed after the onset of rebleeding.

CONCLUSION

Patients aged 80 years or greater had the highest risk of rebleeding and death. For patients below 80 years of age, significant factors related to a fatal outcome included co-morbid illness, complications and the need for mechanical ventilation. For patients aged 80 years or older, the significant factors were ulcer size greater than 2 cm and admission with serum bilirubin level above 20 mmol/l. Endoscopic treatment for the very elderly was effective if carried out early.

Expression of p53 in recurrent nodal metastasis from nasopharyngeal carcinoma (NPC)

This study reports the incidence of p53 expression in 40 patients with recurrent nodal metastasis from nasopharyngeal carcinoma (NPC) and its prognostic value in this group of patients. Immunohistochemical staining using monoclonal antibody specific for human p53 protein was performed on the tumour-bearing nodes from 40 patients. The results were divided into four grades (I, negative; II, < 10% of cells positive; III, 10-50% of cells positive; and IV, > 50% of cells positive). The staining scores were correlated with histological tumour types, subsequent recurrence and survival. All patients had undergone neck irradiation. Lymph node specimens from six patients (15%) showed positive staining of nuclear p53 protein. The distribution among the different grades was: three (7.5%) for II, two (5%) for III and one (2.5%) for IV. Patients with p53-overexpressed tumours had a significantly higher number of tumour-bearing lymph nodes. There was no correlation of p53 expression with histological tumour types, second tumour recurrence and survival. Expression of p53 appears to be uncommon in patients with recurrent nodal metastases in NPC. It did not have prognostic value in this particular series of patients.

Current status of breast cancer in Hong Kong

OBJECTIVE

To study the mode of presentation, the tumor, nodes, metastasis (TNM) staging and the efficacy of multimodal treatment of breast cancer among Chinese women treated in Queen Mary Hospital.

METHODS

The available records of all breast cancer patients treated between January 1980 and December 1994 were reviewed. The mode of presentation, the TNM staging of the disease, estrogen receptor status and the mode of surgical and adjuvant treatment were studied. Statistical correlation was performed between the factors studied and the survival time.

RESULTS

Seven hundred and one cases of breast cancer were identified. The mean age of the patients was 56.6 years (range, 20-98 years). The most common complaint was the presence of a mass which occurred in 635 (90.6%) patients and 454 (71.5%) of these patients were painless. The majority of patients had T2 tumours (51.8%) and stage II disease (59.6%), but only 86 (12.3%) patients underwent breast conservative therapy (BCT). Estrogen receptor was positive in 43% of patients. Two hundred and ninety (41.4%) patients were node positive and the mean number of involved nodes was 3.8 per patient. Adjuvant chemotherapy was given to 125 node positive patients, adjuvant tamoxifen to 188 patients and both to 63 patients. Univariate analyses of factors possibly affecting survival showed that advanced stage disease and nodal involvement were associated with a significantly lower survival time. Among the node positive patients, those with seven or more involved nodes had a shorter survival. The types of surgery and adjuvant treatment (for node positive patients) had no direct correlation with survival.

CONCLUSION

Our results showed that the majority of our patients presented with a painless mass and the final outcome was determined by the tumour load at the time of presentation (TNM staging and nodal status).