Intensive Chemotherapy with Cisplatin, Doxorubicin, Cyclophosphamide, Etoposide and Granulocyte Colony-stimulating Factor for Advanced Thymona or Thymic Cancer: Preliminary Results

A study was conducted to evaluate the impact of cisplatin, doxorubicin,cyclophosphamide and etoposide (PACE) with granulocyte colony-stimulatingfactor (G-CSF) on advanced thymoma or thymic cancer. BetweenAugust 1989 and December 1994, 14 patients with invasive, metastaticor recurrent thymoma or thymic cancer were treated with cisplatin(80 mg/m², on day 1), doxorubicin (45 mg/m², on day 1), cyclophosphamide(800 mg/m², on day 1) and etoposide (80 mg/m², on day 1–3)with G-CSF (90 mg/m², on day 5–18) at the National CancerCenter Hospital, Tokyo. Courses were repeated every 3 or 4 weeksfor a maximum of 4 cycles. Twelve patients were treated with2 or more courses of PACE. Two patients were treated with onlyone course, one refused and another required emergency thoracicradiotherapy after one course of PACE. Six patients had partialresponses (3 thymomas and 3 thymic cancers) but there were nocomplete remissions (response rates, 42.9%; 95% confidence interval,17.7% to 71.1%). Moderate hematological toxicities were observed:grade 3 or 4 leukopenia, neutropenia, anemia and thrombocytopeniain 10, 13, 8 and 6 patients, respectively. Six patients developedinfections that required antibiotics. Surgical resection orthoracic radiotherapy after PACE treatment was performed in2 and 7 patients, respectively. The overall median survivaltime was 14.7 months (range, 5.9 to 59.7 months). For 9 patientswho had received no prior treatment before chemotherapy, themedian survival time was 8.9 months, and one patient survivedfor 4 years and is still alive. In conclusion, PACE with G-CSFfrequently produces objective remissions in patients with advancedthymoma or thymic cancer. A large-scale intergroup study isnecessary to determine the impact of this regimen on advancedthymoma and thymic cancer.     

Prospective Evaluation of the Feasibility of Cisplatin-based Chemotherapy for Elderly Lung Cancer Patients with Normal Organ Functions

A study was conducted to examine the feasibility of cisplatin-based chemotherapy in elderly patients (75 years old) with advanced non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). Thirty-four patients were enrolled between September 1993 and December 1994. Patients with normal organ function and good performance status (PS) received cisplatin-based chemotherapy (cisplatin 80 mg/m² on day 1 and vindesine 3 mg/m² on days 2 and 8 for NSCLC, or cisplatin 80 mg/ m² on day 1 and etoposide 100 mg/m² on days 2 to 4 for SCLC). Ten patients (29%) were eligible for this study, 7 with NSCLC and 3 with SCLC. Reasons for exclusion were ischemic heart disease in 14, poor PS (2) in 11, reduced creatinine clearance (Ccr) in 10, abnormal electrocardiogram without ischemia in 9 and noncompliance with the protocol in 2 patients. Eight patients had two or more reasons. Nine of the 10 eligible patients were able to tolerate 2 or more courses of chemotherapy. All 3 patients with SCLC responded (1 complete response and 2 partial response), but only 1 of the patients with NSCLC achieved partial response. Toxicity was evaluated according to Japan Clinical Oncology Group criteria. All but one patient experienced grade 4 neutropenia, and 6 patients had infectious episodes requiring antibiotics. Grade 3 anemia and thrombocytopenia were observed in 1 and 2 patients, respectively. Non-hematological toxicities were mild. Only 10 of 34 patients (29%) satisfied our eligibility criteria and they experienced severe myelotoxicity. We conclude that chemotherapy should be given carefully to elderly patients even if they appear to have normal organ function.     

Reactivity of anti-AraC-resistant cell monoclonal antibody, YU-311, in formalin-fixed paraffin-embedded specimens of various hematopoietic disorders

YU-311 is a monoclonal antibody reacting with cytosine arabinoside (AraC)-resistant human leukemic cell line and identifies a 92 kDa membrane protein. We have examined YU-311 reactivity with various hematopoietic disorders by an immunohistochemical method and evaluated a correlation between YU-311 expression and refractoriness to chemotherapy, retrospectively. YU-311 reacted with AraC-resistant human leukemia cell lines, in which a 92 kDa membrane protein was identified by Western blotting, whereas drug-resistant cell lines to other than AraC failed to express YU-311 antigen. The frequency of YU-311 positivity was significantly increased in relapsed cases. Only five cases were positive for YU-311 at diagnosis and 24 cases at relapse. Unexpectedly, only eight cases of relapsed leukemia/lymphoma expressed YU-311 and P-glycoprotein simultaneously. Most of the YU-311-positive relapsed cases showed clinical refractoriness for chemotherapy and then failed to induct complete remission or relapsed at short periods with short disease-free duration. These findings indicate that YU-311 expression is closely associated with some aspects of drug resistance, especially with AraC resistance.     

Developed new agents for lung cancer

Platinum-based chemotherapy is considered to be the standard chemotherapy of non-small cell lung cancer (NSCLC) at present. New agents such as irinotecan, paclitaxel, docetaxel, vinorelbine, gemcitabine, topotecan, and amurubicin were developed in the 1990s. Combination chemotherapy using new agents improved survival rates compared with the classic regimen. Irinotecan, paclitaxel, docetaxel, vinorelbine, and gemcitabine have been confirmed to be effective against NSCLC. However, chemotherapy for NSCLC is controversial because the differences in the efficacies of combination chemotherapies including new agents have not been recognized in randomized controlled trials. The Four-Arms Cooperative Study is an ongoing postmarketing clinical trial in Japan. The a ntitumor agents irinotecan, topotecan, paclitaxel, and amurubicin have been confirmed to be effective in small cell lung cancer (SCLC). The combination of etoposide and cisplatin (PE) is the standard regimen for SCLC in Western countries. However, the combination of irinotecan and cisplatin (CP) resulted in higher response rates and better median survival times than PE for extensive-disease SCLC in a JCOG trial. At present, CP is considered to be the standard chemotherapy regimen to treat SCLC in Japan. The development of new agents, particularly molecular target-based drugs and multimodality treatment, is necessary to improve the therapeutic results in lung cancer further.     

Is DOPA a neurotransmitter?

Historically, 3,4-dihydroxyphenylalanine (DOPA) has been considered to be an inert amino acid that alleviates the symptoms of Parkinson's disease by its conversion to dopamine via the enzyme aromatic L-amino acid decarboxylase. In contrast to this generally accepted idea, we propose that DOPA itself is a neurotransmitter and/or neuromodulator in addition to being a precursor of dopamine. Several criteria such as synthesis, metabolism, active transport, existence, physiological release, competitive antagonism and physiological or pharmacological responses must be satisfied before a compound is accepted as a neurotransmitter. Recent evidence suggests that DOPA fulfills these criteria in its involvement in baroreflex neurotransmission.     

Suppression of cytotoxin-induced cell death in isolated hepatocytes by tea catechins

To elucidate the hepatoprotective effects of green tea catechins, the following experiments were conducted utilizing (−)-epigallocatechin-3-gallate (EGCG), the major component of green tea catechin, together with other catechins. The protective effects of catechins against hepatotoxins, bromobenzene or rubratoxin B, were examined in primary cultures of rat hepatocytes. Bromobenzene and rubratoxin B are known to induce necrosis and apoptosis of cells, respectively. After 24-h treatment with toxin, EGCG and (−)-epigallocatechin-3-(3″-O-methyl)gallate (EGCg-3″-OMe) suppressed the bromobenzene-induced morphological change and dose-dependently prevented bromobenzene-induced cell death. Both catechins also prevented apoptotic cell death caused by rubratoxin B. In rubratoxin B-treated cells, both catechins were found to suppress the activation of caspase-3 by rubratoxin B. The results in the present study suggest that EGCG and EGCg-3″-OMe are potent hepatoprotective agents. This report is the first to show that catechins suppress cytotoxin-induced cell death.     

Antitumor-promoting constituents from Dioscorea bulbifera L. in JB6 mouse epidermal cells

An antitumor-promoting effect was found in the extracts/ingredients of a plant used as a traditional medicine in mainland China, using the neoplastic transformation assay of mouse epidermal JB6 cell lines. The ethyl acetate soluble fraction of 75% ethanol extract of the rhizomes of Dioscorea bulbifera L. showed an inhibitory effect against the tumor promotion of JB6 (Cl 22 and Cl 41) cells induced by a promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Further investigation on the constituents of the EtOAc fraction from the rhizomes revealed the chemical structure to be kaempferol-3,5-dimethyl ether (1), caryatin (2), (+)-catechin (3), myricetin (4), quercetin-3-O-galactopyranoside (5), myricetin-3-O-galactopyranoside (6), myricetin-3-O-glucopyranoside (7) and diosbulbin B (8). Constituent antitumor-promoting activities were also examined in the same way. Compounds 1-7, characterized as flavonoids with the two hydroxyl groups at C-7 and C-4', showed the most potent inhibitory effect, but there seemed to be differences in the inhibitory effect between flavonol aglycones and flavonol glycosides. Compared with (-)-epicatechin, (+)-catechin exhibited much stronger inhibitory activity which suggested that chemical stereo structures of compounds affect the efficiency of inhibition. Compound 8 showed moderate activity. The constituents with antitumor-promoting activity from this plant are reported for the first time.     

Complication-free laryngeal surgery after irradiation failure with prostaglandin E1 administration

To examine the usefulness and efficacy of administration of prostaglandin E1 (PGE1) after laryngeal surgery in patients who were previously treated with radiotherapy, we retrospectively examined the clinical data of 12 patients who had undergone partial laryngectomy and 21 patients who had undergone total laryngectomy. Complications were observed in 5 of the 7 cases treated with partial laryngectomy without PGE1 administration, while no complications were observed in the 5 cases treated with PGE1 after operation. Also, complications, including major leakage, were observed in 6 of the 15 patients who underwent total laryngectomy without PGE1, and no complications were observed in the 6 patients who received PGE1. The hospital stay was shorter for the patients treated with PGE1 than for those not receiving such treatment. Although this study was a small, nonrandomized pilot trial, the results indicated that PGE1 administration may be useful and effective for patients who undergo laryngeal surgery after irradiation failure, in decreasing the risk of postoperative complications and increasing the quality of life of the patients.     

Diet restriction impairs extracellular signal-regulated kinase activation of peritoneal exudative cells after N-formyl-methionyl-leucyl-phenylalanine stimulation in a murine peritonitis model

BACKGROUND: Phosphorylation of extracellular signal-regulated kinase (ERK) enhances various inflammatory responses in immune cells. It is unknown whether dysfunction of immune cells during malnutrition is attributed to derangement of ERK activation. METHODS: Male Institute of Cancer Research (ICR) mice received chow (146 g/kg per day, ad libitum or 36.5 g/kg per day, diet-restricted) for 7 days. Mice (n = 55) were given 6.5 mg/kg of an ERK inhibitor (PD98059) or vehicle intraperitoneally (IP), at 2 hours before cecal ligation and puncture (CLP). Survival was observed up to 60 hours. Detection of phosphorylated ERK (pERK) in the peritoneal exudative cells (PECs) was done as follows. In a separate study, PECs were harvested by peritoneal lavage 2 hours after an IP injection of 1% glycogen. PECs were incubated with or without 100 nmol/L N-formyl-methionyl-leucyl-phenylalanine (fMLP) for 1 minute. PEC ERK activation was detected with Western blot analysis (n = 38), by densitometric quantification, and with a laser scanning cytometer (LSC; n = 13). Subpopulations of PECs were determined by Wright-Giemsa staining. Unstimulated pERK expression was normalized to 100% for Western blot analysis. RESULTS: Diet restriction reduced survival after CLP compared with the ad libitum mice. ERK inhibition showed no effect on survival in diet-restricted mice but reduced survival in ad libitum mice. There were no differences in subpopulations of PECs 2 hours after glycogen injection between the groups. Western blot analysis revealed that fMLP stimulation significantly increased the phosphorylation of ERK1/2 in PECs from the ad libitum group (ERK1, 199 +/- 41%; ERK2, 211 +/- 49%; p < .03) but not in those from diet-restricted mice (ERK1, 98 +/- 10%; ERK2, 91 +/- 9%). Mean fluorescence intensity (MFI) of pERK in PECs obtained by LSC was significantly elevated after fMLP in the ad libitum group (from 19.4 +/- 1.5 MFI to 22.4 +/- 1.2 MFI; p < .05) but did not change in the diet-restricted group (from 19.4 +/- 1.8 MFI to 19.1 +/- 1.5 MFI). CONCLUSIONS: ERK activation is essential for survival in this murine sepsis model. Impaired ERK activation of PECs may, at least in part, impair host defense during malnutrition.