Absence of p53 Overexpression and Favorable Response to Cisplatin-based Neoadjuvant Chemotherapy in Urothelial Carcinomas

It has been controversial whether cancer cells harboring loss or inactivation of the tumor suppressor p53 are resistant or sensitive to DNA-damaging agents including cisplatin and doxorubicin. Overexpression of mdm2 oncoprotein, a negative regulator of p53, is assumed to be an alternative to p53 dysfunction. Archival urothelial carcinoma specimens obtained from 60 patients prior to cisplatin-based chemotherapy were immunohistochemically studied for overexpression of p53 and mdm2. Thirty-two patients (group I) were treated with chemotherapy in the neoadjuvant setting, while 28 patients (group II) underwent chemotherapy for distant metastases or inoperable locoregional tumors. In group I, the responsiveness was correlated with staining status of p53 ( P =0.0225) and the combination of p53 and mdm2 ( P =0.0497). Negative staining of p53 and negative for both p53 and mdm2 could have predicted favorable response to chemotherapy in 16 of 18 (88.9%) and in 12 of 13 (92.3%) tumors, respectively. On the other hand, p53-positive and p53 and/or mdm2-positive staining could have predicted poor response only in 7 of 14 (50.0%) and 8 of 19 (42.1%) tumors, respectively. Disease-specific survival of the p53-negative group was significantly superior to that of the p53-positive group ( P =0.0086). Difference in survival did not become more significant when overexpression of mdm2 was taken into consideration ( P =0.0456). In contrast, in group II, there was no correlation of responsiveness to chemotherapy or survival with p53- or p53/mdm2-staining status. The patients with urothelial carcinomas negative for overexpression of p53 will benefit from neoadjuvant chemotherapy. From clinical viewpoint, however, p53 status alone or the combination of p53 and mdm2 status is not enough to identify those patients who will not benefit from the treatment.     

Mutations of the epidermal growth factor receptor gene predict prolonged survival after gefitinib treatment in patients with non-small-cell lung cancer with postoperative recurrence.

PURPOSE: To evaluate the relationship between mutations of the epidermal growth factor receptor (EGFR) gene and the effectiveness of gefitinib treatment in patients with recurrent lung cancer after pulmonary resection. PATIENTS AND METHODS: We sequenced exons 18-21 of the EGFR gene using total RNA extracted from 59 patients with lung cancer who were treated with gefitinib for recurrent lung cancer. Gefitinib effectiveness was evaluated by both imaging studies and change in serum carcinoembryonic antigen (CEA) levels. RESULTS: EGFR mutations were found in 33 patients (56%). Of these mutations, 17 were deletions around codons 746-750 and 15 were point mutations (12 at codon 858, three at other codons), and one was an insertion. EGFR mutations were significantly more prevalent in females, adenocarcinoma, and never-smokers. Gefitinib treatment resulted in tumor shrinkage and/or CEA decrease to less than half of the baseline level in 26 patients, tumor growth and/or CEA elevation in 24 patients, and gefitinib effect was not assessable in nine patients. Female, never-smoking patients with adenocarcinoma tended to respond better to gefitinib treatment. Gefitinib was effective in 24 of 29 patients with EGFR mutations, compared with two of 21 patients without mutations (P < .0001). Of note, del746-750 might be superior to L858R mutations for prediction of gefitinib response. Patients with EGFR mutations survived for a longer period than those without the mutations after initiation of gefitinib treatment (P = .0053). CONCLUSION: EGFR mutations were a good predictor of clinical benefit of gefitinib in this setting.     

A pilot study of weekly paclitaxel administration for patients with relapsed cervical cancer after heavy medication

No standard therapy has been established for patients with relapsed cervical cancer after applying radical hysterectomies including lymphadenectomies, radiotherapy, and platinum-based chemotherapy. This study was designed to evaluate the effectiveness and safety of weekly paclitaxel (TXL) therapy in patients who suffered a cervical cancer relapse after heavy treatment. The candidates for the study included patients with cervical cancer that recurred after radical therapy (including lymphadenectomies), postoperative radiotherapy, and platinum-based chemotherapy, the lesions of which could be evaluated by imaging diagnosis. Patients received 80 mg/m2 of TXL by intravenous drip in one hour. Premedications included 10 mg of dexamethasone (iv), 50 mg of cimetidine (iv), and 50 mg of diphenhydramine (po) administered 30 minutes before the TXL treatment. This procedure was repeated weekly on an ongoing basis. The median progression-free survival was 14 months (range: 0 to 24 months), and the median overall survival 19 months (range: 6 to 24 months). Grade-3 or higer hematologic toxicity was observed for leukocyte (total WBC) and neutrophil/granulocyte in one patient (12.5%), but was controllable with GCSF. The weekly TXL therapy was effective against cervical cancer relapse after heavy treatment and its toxicity was tolerable.     

Inhibition of Liver Metastasis of Human Gastric Carcinoma by Angiogenesis Inhibitor TNP-470

The anti-tumor and anti-metastatic effects of TNP-470, an angiogenesis inhibitor, and mitomycin C (MMC), a representative anti-neoplastic agent, were investigated using our established liver-metastasizing gastric carcinoma line, AZ-H5c. AZ-H5c was injected into the spleen of nude mice which had been randomly divided into 4 groups; a control group given saline solution, a group receiving 15 mg/kg TNP-470, a group receiving 30 mg/kg TNP-470 and a group receiving 2 mg/kg MMC. TNP-470 was given s.c. on alternate days for 5 weeks from day 10 after intrasplenic injection, and MMC was administered intraperitoneally (i.p.) once a week from day 10 after intrasplenic injection. In the control group, liver metastasis developed in 13 of 16 mice (81%). Liver metastasis developed in 6 of 11 mice (55%) receiving MMC. In contrast, liver metastasis developed in 4 of 8 mice (50%) receiving 15 mg/Kg TNP-470, and in 0 of 14 mice (0%) receiving 30 mg/kg TNP-470. However, TNP-470 had no effect on the tumor growth. These results indicate that the angiogenesis inhibitor TNP-470 has a strong inhibitory activity against in vivo liver metastasis of human gastric carcinoma.     

Dual Effects of Liquiritigenin on the Proliferation of Bone Cells: Promotion of Osteoblast Differentiation and Inhibition of Osteoclast Differentiation

Bone is constantly controlled by a balance between osteoblastic bone formation and osteoclastic bone resorption. Liquiritigenin is a plant‐derived flavonoid and has various pharmacological effects, such as antioxidative, antitumor, and antiinflammatory effects. Here, we show that liquiritigenin has dual effects on the proliferation of bone cells, regarding the promotion of osteoblast differentiation and the inhibition of osteoclast differentiation. Liquiritigenin‐treated murine osteoblastic MC3T3‐E1 cells showed an increased alkaline phosphatase activity and enhanced phosphorylation of Smad1/5 compared with untreated cells. Moreover, liquiritigenin inhibited osteoclast differentiation, its bone‐resorption activity through slightly decreased the phosphorylation of extracellular signal‐regulated kinase, c‐Jun N‐terminal kinase, and inhibitor of nuclear factor kappa Bα; however, the phosphorylation of Akt and p38 slightly increased in bone marrow‐derived osteoclasts. The expression levels of the osteoclast marker proteins nuclear factor of activated T‐cell cytoplasmic‐1, Src, and cathepsin K diminished. These results suggest that liquiritigenin may be useful as a therapeutic and/or preventive agent for osteoporosis or inflammatory bone diseases. Copyright © 2015 John Wiley & Sons, Ltd.     

A Case of Leiomyosarcoma Associated with Humoral Hypercalcemia of Malignancy: Demonstration of Biological and Immunological Activities of Parathyroid Hormone-related Protein in the Tumor Extract

Hypercalcemia occurred in a patient with leiomyosarcoma when multiple lung metastases developed. Despite normal plasma parathyroid hormone (PTH) levels and low 1,25-dihydroxyvitamin D, this hypercalcemic patient had a marked hypercakiuria and phosphatnria associated with an increased excretion of nephrogenous cyclic AMP (NcAMP). Administration of cisplatin ameliorated both the hypercalcemia and hypercalciuria without any reduction in tumor size or NcAMP excretion. Terminally, acute pancreatitis occurred producing a profound hypocalcemia. In the extract of tumor tissue obtained post mortem, bioactivity stimulating the generation of cyclic AMP in osteogenic cells was demonstrated along with the immunoreactive PTH-related protein (PTH-rP). This is the first report of a solid non-epithelial malignancy producing PTH-rP and associated with humoral hypercalcemia of malignancy. The hypercalcemia in this case caused acute pancreatitis, which led to a profound hypocalcemia     

The degree of microRNA-34b/c methylation in serum-circulating DNA is associated with malignant pleural mesothelioma

Objectives

Malignant pleural mesothelioma (MPM) is an aggressive tumor with a poor prognosis. microRNA-34b/c (miR-34b/c), which plays an important role in the pathogenesis of MPM, is frequently downregulated by DNA methylation in approximately 90% of MPM cases. In this study, we estimated the degree of miR-34b/c methylation in serum-circulating DNA using a digital methylation specific PCR assay (MSP).

Materials and methods

A real-time MSP assay was performed using the SYBR Green method. The melting temperature (Tm) of each PCR product was examined using a melting curve analysis. For a digital MSP assay, 40 wells were analyzed per sample. A total of 110 serum samples from 48 MPM cases, 21 benign asbestos pleurisy (BAP) cases, and 41 healthy volunteers (HVs) were examined.

Results

Positive range of Tm value for miR-34b/c methylation was defined as 77.71–78.79 °C which was the mean ± 3 standard deviations of 40 wells of a positive control. The number of miR-34b/c methylated wells was counted per sample according to this criterion. The number of miR-34b/c methylated wells in MPM cases was significantly higher than that in BAP cases (P = 0.03) or HVs (P < 0.001). Advanced MPM cases tended to have higher number of miR-34b/c methylated wells than early MPM cases. Receiver–operating characteristic (ROC) curve analysis revealed that three number of miR-34b/c methylated wells per sample was the best cut-off of positivity of MPM with a 67% of sensitivity and a 77% specificity for prediction. The area under the ROC curve was 0.77.

Conclusions

Our digital MSP assay can quantify miR-34b/c methylation in serum-circulating DNA. The degree of miR-34b/c methylation in serum-circulating DNA is associated with MPM, suggesting that this approach might be useful for the establishment of a new detection system for MPM.     

XPS Investigation on Improving Hydrogen Sorption Kinetics of the KSiH3 System by Using Zr-Based Catalysts

The superior hydrogen storage properties makes the KSiH₃ system a potential hydrogen storage material for practical applications. A theoretical capacity of 4.3 wt% bring this material to the front line of all the available hydrogen storage materials; however, the activation barrier of the reaction restricts the system to absorb and desorb hydrogen reversibly at elevated temperatures even if the thermodynamics suggest its room temperature operation. Several catalysts have already been tested to enhance its kinetic properties. In this work, the efforts were made to reduce the activation energy by using Zr-based catalysts to the KSi/KSiH₃ system. The value of activation energy was found to be lowest (i.e., 87 kJ mol⁻¹⁾ for the ZrH₂-added KSiH₃ system. The mechanism of this improvement was investigated by using X-ray photoelectron spectroscopy (XPS).