Induced luteolysis in the primate: rapid loss of luteinizing hormone receptors

The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.      

Rapid molecular characterization of Hb H disease in Chinese by polymerase chain reaction

Summary We have developed a rapid method to molecularly distinguish different types of Hb H disease. The study depended on (a) most of the Hb H disease in Taiwan having an-thalassemia-1 of the Southeast Asia type (-SEA) in one allele and (b) the differences of X box of-globin gene cluster in the other allele. To detect the -SEA allele, we utilized the primers located on either side of the breakpoint to do PCR, then characterized the amplified products. For the other allele, we sequenced part of the X box, and found that bases –2803 to –2461 of the X box of – ^3.7 belonged to the X box of ₂ globin gene. In – ^4.2, the bases belonged to the X box of ₁ globin gene, whereas in ^cs it contained both X boxes of ₁ and ₂ globin genes. There was anMboII site at this region of the X box of ₂ globin gene. We utilized PCR to amplify this region and digested it with restriction enzymeMboII, then combined it with another PCR of different primer pairs to molecularly diagnose different types of Hb H disease. One hundred and one cases of Hb H disease from different families were studied: all of the cases had one allele of -SEA deletion, while the other allele showed that 52/101 were – ^3.7, 41/101 were ^cs , 7/101 were – ^4.2, and 1/101 was – ^G.Taichung. Of 52 cases of Hb H with – ^3.7, 47 were type-I deletion and five were type-II deletion.     

Vaccination with different HSV-1 glycoproteins induces different patterns of ocular cytokine responses following HSV-1 challenge of vaccinated mice.

We previously reported that vaccination of BALB/c mice with different baculovirus expressed HSV-1 glycoproteins induced varying degrees of protection against HSV-1 ocular challenge, ranging from complete protection to no protection, to exacerbation of eye disease. To correlate specific local immune responses with protection and exacerbation of corneal scarring, we examined immune cell infiltrates in the cornea after ocular HSV-1 challenge of vaccinated mice. Mice were vaccinated with gD, which completely protects against corneal scarring, gG, which produces no protection against corneal scarring, or gK, which exacerbates corneal scarring. Cryostat sections of cornea were taken at different times after challenge and examined for infiltrating cells containing IL-2, IL-4, IFN-gamma, IL-6, or TNF-alpha. No corneal infiltrates were seen before challenge or 1 day after ocular challenge in any groups. By days 3-7, many cells containing IL-4 and IFN-gamma, but few cells containing IL-2, had infiltrated into the corneas of gG or mock vaccinated mice. At the same times, many cells containing IL-2, but few cells containing IL-4 or IFN-gamma, were seen in the corneas of gD vaccinated mice. In contrast, the corneas of mice vaccinated with gK contained large amounts of IL-2, IFN-gamma, and IL-4. Our results suggest that: (1) corneas from gD vaccinated mice had no corneal disease and developed a response highly biased toward IL-2 responses; (2) corneas from gG or mock vaccinated eyes had significant corneal disease and developed a mostly IL-4 and IFN-gamma cytokine response; and (3) corneas from gK vaccinated mice had exacerbated corneal disease and developed strong IL-2, IL-4 and IFN-gamma cytokine responses.     

Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control

OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.      

A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma

We examined the relationship between a functional polymorphism (667C-- >T, ala-->val) of the methylenetetrahydrofolate reductase gene (MTHFR) and the risk of colorectal adenomas in the prospective Nurses' Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.84-2.17] was not significantly associated with risk of adenomas. This lack of association was observed for both small (RR = 1.36, 95% CI 0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore, there was no significant interaction between this polymorphism and consumption of either folate, methionine or alcohol. We also examined the relationship of a newly identified polymorphism (asp919gly) of the methionine synthase gene (MS) with the risk of colorectal adenomas in the same population. The MS gly/gly polymorphism was also not significantly associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70). These results, which need to be confirmed in other studies, suggest that the MTHFR val/val polymorphism, which has been previously inversely associated with risk of colorectal cancer, plays a role only in a late stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may protect against malignant transformation in the subset of benign adenomas, which may progress to malignancy.      

Mutation in the tyrosine kinase domain of epidermal growth factor receptor is a predictive and prognostic factor for gefitinib treatment in patients with non-small cell lung cancer.

PURPOSE: Mutations in epidermal growth factor receptor (EGFR) can be used to predict the tumor response of patients receiving gefitinib for non-small cell lung cancer (NSCLC). We investigated the association between mutations in EGFR tyrosine kinase domain and tumor response and survival in gefitinib-treated NSCLC patients. EXPERIMENTAL DESIGN: EGFR mutations in exons 18 to 21 were analyzed by DNA sequencing of paraffin-embedded tumor tissues from gefitinib-treated NSCLC patients. The results were correlated with clinical variables. RESULTS: EGFR mutations were found in 61.1% (33 of 54) of cases; response rate and disease control rate were 56.8% and 68.5%, respectively. There was no significant difference in mutation rates between adenocarcinoma (29 of 43) and nonadenocarcinoma (4 of 11; P = 0.085). However, all four nonadenocarcinomas with EGFR mutations had no response to gefitinib. Presence of EGFR mutations was the only independent predictor for disease control (P = 0.003) and tumor response (P = 0.017) in multivariate analysis; positive predictive values were 87.9% and 70.8% and negative predictive values were 61.9% and 69.2%, respectively. In comparison with patients whose tumor was negative for EGFR mutations, patients with EGFR mutations had better progression-free survival (median, 7.6 versus 1.7 months; P = 0.011) and overall survival (median, 14.7 versus 4.7 months; P = 0.046). CONCLUSIONS: Mutations in EGFR tyrosine kinase correlate with treatment response and survival in gefitinib-treated NSCLC patients and can be used as a predictive and prognostic factor. Thus, analysis of EGFR tyrosine kinase mutations in lung adenocarcinoma is of clinical significance, as it can permit the customization of treatment with EGFR tyrosine kinase inhibitors.     

Trastuzumab-induced cardiotoxicity in elderly women with HER-2-positive breast cancer: a meta-analysis of real-world data

Background: We conducted a meta-analysis to assess the overall risk of cardiac toxicity associated with trastuzumab treatment in elderly breast cancer patients.

Methods: We searched databases from PubMed, EMBASE and Cochrane Central Registry of Controlled Trials to identify relevant studies. Statistical analyses were conducted to calculate the incidence rate, overall hazard ratio (HR) and 95% CIs using a fixed effects model.

Results: A total of 116,342 and 360 elderly patients from five cohort studies and two randomized clinical trials (RCTs) were included for analysis. The pooled incidences of symptomatic congestive heart failure (CHF) and CHF/HF/CM were 6.4% (95% CI 4.1% – 9.4) and 16.4% (95% CI 16.19% – 16.61) in patients with median age of 67.5 years from two RCTs and in patients with median age of 67.5 (60 – 75), 71 (66 – 80+), 74.5 (65 – 89), 75 (66 – 81+) and 79.5 (60 – 99) from five cohort studies, respectively. Trastuzumab was significantly correlated with an increased risk of defined cardiac toxicities in five cohort studies (HR = 1.89, 95% CI 1.72 – 2.07, p < 0.00001) and two RCTs (HR = 3.00, 95% CI 1.71, 5.26, p < 0.00001). Sub-group analysis showed that the anthracycline-based chemotherapy increased the risk of CHF/HF and CM in patients among five cohort studies (HR = 2.16, 95% CI: 1.8 – 1.87, p < 0.00001).

Conclusion: Trastuzumab is likely associated with an increased risk of cardiac toxicity in elderly patients with HER-2-positive breast cancer. Carefully monitoring cardiac function in elderly patients receiving trastuzumab, particularly with concurrent use of anthracycline, is warranted.     

Identification of a novel nonsense mutation in the rod domain of GFAP that is associated with Alexander disease

Alexander disease (AxD) is an astrogliopathy that primarily affects the white matter of the central nervous system (CNS). AxD is caused by mutations in a gene encoding GFAP (glial fibrillary acidic protein). The GFAP mutations in AxD have been reported to act in a gain-of-function manner partly because the identified mutations generate practically full-length GFAP. We found a novel nonsense mutation (c.1000 G>T, p.(Glu312Ter); also termed p.(E312*)) within a rod domain of GFAP in a 67-year-old Korean man with a history of memory impairment and leukoencephalopathy. This mutation, GFAP p.(E312*), removes part of the 2B rod domain and the whole tail domain from the GFAP. We characterized GFAP p.(E312*) using western blotting, in vitro assembly and sedimentation assay, and transient transfection of human adrenal cortex carcinoma SW13 (Vim⁺) cells with plasmids encoding GFAP p.(E312*). The GFAP p.(E312*) protein, either alone or in combination with wild-type GFAP, elicited self-aggregation. In addition, the assembled GFAP p.(E312*) aggregated into paracrystal-like structures, and GFAP p.(E312*) elicited more GFAP aggregation than wild-type GFAP in the human adrenal cortex carcinoma SW13 (Vim⁺) cells. Our findings are the first report, to the best of our knowledge, on this novel nonsense mutation of GFAP that is associated with AxD and paracrystal formation.