Metastasis to para-aortic lymph nodes cephalad to the renal veins in patients with ovarian cancer.

BACKGROUND: In patients with epithelial ovarian cancer, whether metastasis to para-aortic lymph nodes located cephalad to the renal veins (supra-renal PAN) should be classified as regional lymph node metastasis or distant metastasis remains controversial. This study was a preliminary retrospective evaluation of the pattern of supra-renal PAN metastasis in patients with epithelial ovarian cancer. METHODS: The subjects were 25 patients with epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer who underwent systematic dissection of the para-aortic nodes, including the supra-renal PAN, and pelvic lymph nodes (PLN). Patient factors, perioperative factors, the number of dissected lymph nodes, and pathological lymph node metastasis were investigated. RESULTS: Supra-renal PAN metastasis was found in 4/25 patients (16.0%). None of the 14 patients with pT1 or pT2 disease had supra-renal PAN metastasis, while 4/11 patients (36.4%) with pT3 or ypT3 disease had such metastases. None of the patients had isolated supra-renal PAN metastasis, while patients with supra-renal PAN metastasis also had multiple metastases to the infra-renal PAN and PLN. CONCLUSIONS: In patients with epithelial ovarian cancer, supra-renal PAN metastases might be considered to be distant rather than regional metastases. Further studies are needed to better define the clinical significance of supra-renal PAN metastasis.

Conservative management of uterine artery pseudoaneurysm occurring during treatment of gestational trophoblastic disease: A case report.

Uterine artery pseudoaneurysm (UAP) is a rare disease that causes genital bleeding during the postpartum period after cesarean section. Uterine artery embolization (UAE) is an effective procedure for UAP. UAP was unexpectedly encountered in a patient with gestational trophoblastic disease; however, this patient was conservatively managed without UAE. UAP can occur during treatment for gestational trophoblastic disease. Since asymptomatic UAP may spontaneously disappear, in the selection of conservative treatment, it is important to carefully monitor patients using transvaginal ultrasonography focusing on the size of the UAP and the speed of internal blood flow.

Ovarian Clear Cell Carcinoma Detected During Long-Term Management of Endometriotic Cysts in Young Patients: Possible Heterogeneity of this Tumor.

Ovarian endometriotic cysts have been identified as the possible origin of ovarian clear cell carcinoma (OCCC), so predicting or preventing future transformation is important. Early detection of clear cell carcinoma is important because it shows low sensitivity to chemotherapy and the prognosis is worse than for other histologic types. We recently treated 2 patients with OCCC. They were both young women with no family history of cancer who received long-term oral contraceptive therapy for endometriotic cysts, and the histologic diagnosis was typical clear cell carcinoma in both patients. However, in Case 1, the tumor was detected by periodic examination, tumor expression of WT1 was positive, and the stage was IA. On the other hand, Case 2 presented with fever of unknown origin, her tumor showed expression of p53, and the stage was IVB. Case 1 is alive with no evidence of disease at 38 months after surgery, while Case 2 died after 19 months despite intensive treatment. These contrasting cases suggest that we need to be aware of the risk of cancer in young women receiving long-term hormone therapy for endometriotic cysts and that OCCC may show greater heterogeneity than what has been reported previously.

Clinical features of long-term survivors of recurrent epithelial ovarian cancer.

BACKGROUND: Although recurrent epithelial ovarian cancer (EOC) is generally regarded as an incurable disease, some patients survive more than 5 years after the first recurrence. The aim of this study was to evaluate the clinical features of patients with recurrent EOC who achieve long-term survival. METHODS: We retrospectively reviewed the medical records of 164 patients with recurrent EOC and analyzed the clinical stage, histologic subtype, primary treatment, disease-free interval (DFI), recurrence site, secondary treatment, and overall survival from the time of the first recurrence (R-OS), using the Kaplan-Meier method and the log-rank test. RESULTS: The median R-OS for all 164 patients was 25 months and the 5-year R-OS rate was 25.4 %. There were no significant differences in R-OS according to the disease stage. The median R-OS was significantly shorter in the 6-12-month DFI group (23 months) than in the ≥12-month DFI group (61 months) (p = 0.0002), while there was no significant difference between the 6-12 and 3-6-month DFI groups (20 months) (p = 0.161). Of the 164 patients, only 14 survived >5 years after the first recurrence. Most of them underwent surgery and/or radiotherapy in combination with chemotherapy and underwent >18 cycles of platinum-based chemotherapy throughout their treatments (median 22 cycles; range 4-44). CONCLUSIONS: If high sensitivity to platinum is maintained, patients with recurrent EOC may have prolonged survival following repeated platinum-based chemotherapy cycles. Moreover, their prognosis improves when chemotherapy is combined with secondary cytoreductive surgery and/or irradiation.

Recurrence patterns of advanced ovarian, fallopian tube, and peritoneal cancers after complete cytoreduction during interval debulking surgery.

OBJECTIVES: Similar to primary debulking surgery, complete resection of all macroscopic diseases during interval debulking surgery (IDS) is the primary objective while using neoadjuvant chemotherapy followed by IDS for advanced ovarian, fallopian tube, and peritoneal cancers. However, most patients develop recurrent disease even after complete cytoreduction during IDS. This study aims to identify recurrence patterns of the ovarian, fallopian tube, and peritoneal cancers in patients who underwent complete cytoreduction during IDS. METHODS: We retrospectively reviewed data of patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers who were treated at our hospital from January 1, 2005, to December 31, 2011. RESULTS: In this study, 105 patients underwent neoadjuvant chemotherapy followed by IDS and achieved complete cytoreduction. The median follow-up period was 42.1 months. Recurrence was documented in 70 patients (66.7%), and 35 (33.3%) showed no evidence of disease. Peritoneal dissemination was the most common recurrence (60.0%) observed. In multivariate analysis, positive peritoneal cytology (P = 0.0003) and elevated pre-IDS serum CA125 levels (P = 0.046) were independent risk factors for recurrence. CONCLUSIONS: After complete cytoreduction during IDS in patients with stage III or IV ovarian, fallopian tube, and peritoneal cancers, positive peritoneal cytology at IDS and elevated pre-IDS CA125 levels are associated with an increased risk of cancer recurrence. Positive peritoneal cytology during IDS is a particularly strong predictive factor for poor outcomes in these patients.

Real-world Safety and Efficacy of Indacaterol Maleate in Patients with Chronic Obstructive Pulmonary Disease: Evidence from the Long-term Post-marketing Surveillance in Japan.

Objective Evidence concerning the safety and efficacy of indacaterol maleate in a real-life setting is limited. The objective of this post-marketing surveillance was to evaluate the real-life safety and efficacy of indacaterol maleate in Japanese patients with chronic obstructive pulmonary disease (COPD). Methods This was a 52-week post-marketing surveillance conducted between April 2012 and December 2018. The safety endpoints included the incidence of adverse events (AEs), serious adverse events (SAEs), and adverse drug reactions (ADRs). The efficacy endpoints included the physician-reported global evaluation of treatment effectiveness (GETE), change from baseline in the COPD assessment test (CAT) results, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and %FEV1 following 4, 12, 26, and 52 weeks of indacaterol administration. Results Of the 1,846 enrolled patients, 1,726 were included in the safety and efficacy analyses. The mean age of the patients was 72.5 years old. Cough, pneumonia and COPD worsening were the most common AEs reported, while pneumonia (1.04%) was the most common SAE, and cough (1.68%) was the most common ADR. GETE showed that 69.70% of patients achieved an excellent/good/moderate response following indacaterol treatment. The CAT score decreased, and lung function parameters (FVC, FEV1 and %FEV1) improved across all the COPD stages following treatment with indacaterol. Conclusion Indacaterol showed a favorable safety and tolerability profile in Japanese patients with COPD without new safety signals observed in real-life settings. These findings demonstrated that indacaterol is an effective maintenance treatment in real-life practice for Japanese patients with COPD.

Cardiovascular safety and effectiveness of vildagliptin in patients with type 2 diabetes mellitus: a 3-year, large-scale post-marketing surveillance in Japan.

Objectives: The dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin is indicated for type 2 diabetes mellitus (T2DM). However, the long-term safety, effectiveness, and clinical relationship with cardiovascular events of vildagliptin have not been evaluated in Japan.Methods: The authors conducted post-marketing surveillance (PMS) to evaluate the safety and effectiveness of vildagliptin in more than 3000 Japanese T2DM patients for up to 3 years. Main assessments included demographics, major adverse cardiovascular events (MACE), adverse events (AEs), adverse drug reactions (ADRs), and glycated hemoglobin (HbA1c).Results: In this PMS, 3831 patients (775 sites) were registered in April 2010 - April 2012. The safety analysis population comprised 3769 patients; 2085 patients were aged ≥65 years, and 240, 411, and 114 had renal impairment, hepatic impairment, and heart failure, respectively. The median treatment duration was 2.7 years. The incidence of MACE was 6.04 cases/1000 person-years, mostly attributable to cerebrovascular events (4.27 cases/1000 person-years). The AE and ADR incidences were 26.0% and 5.3%, respectively. The incidence of hypoglycemia was 0.6%. No significant changes in body weight occurred and mean change in HbA1c from baseline at final assessment was -0.74 ± 1.41% (p < 0.0001).Conclusions: In real-world clinical settings, vildagliptin was well tolerated, with similar profiles as previously reported.

Safety and efficacy of vildagliptin: 52-week post-marketing surveillance of Japanese patients with type 2 diabetes in combination with other oral antidiabetics and insulin.

Background: Vildagliptin is a dipeptidyl peptidase-4 inhibitor that reduces glycemia in patients with type 2 diabetes mellitus (T2DM). When approved in 2013, data on vildagliptin combined with >750 mg/day metformin in Japanese patients were limited. There is a need to confirm the safety and efficacy of vildagliptin in combination with oral antidiabetic drugs (OADs).Research design and methods: This 52-week post-marketing surveillance (PMS) observational study in Japanese T2DM patients evaluated the safety and efficacy of vildagliptin in combination with OADs including high-dose metformin or insulin but excluding combination with sulfonylureas alone.Results: During this survey of 3006 Japanese T2DM patients, 13.61% of patients experienced adverse events (AEs) and 2.20% reported a serious AE (SAE). The frequency of AEs/SAEs was similar when in combination with biguanides (12.93%/1.46%), metformin ≥1000 mg/day (12.92%/1.22%), metformin <1000 mg/day (12.62%/1.54%), thiazolidine derivatives (16.71%/2.86%), α-glucosidase inhibitors (13.18%/1.90%), rapid-acting insulin secretagogues  (glinides) (20.41%/5.71%), or insulin (15.87%/2.47%). The mean ± SD changes from baseline at endpoint in glycated hemoglobin and fasting blood glucose were -0.76 ± 1.27% and -23.3 ± 57.3 mg/dL, respectively, and these changes were consistent, regardless of concomitant OAD.Conclusions: Long-term vildagliptin combination therapy is safe and effective in Japanese T2DM patients in real-world settings.

Bevacizumab Plus Direct Oral Anticoagulant Therapy in Ovarian Cancer Patients with Distal Deep Vein Thrombosis.

BACKGROUND AND OBJECTIVE: Administration of bevacizumab to ovarian cancer patients with distal deep vein thrombosis (DVT) is problematic because of lack of evidence about the likely outcomes. We conducted a preliminary study in ovarian cancer patients with DVT who received bevacizumab combined with a direct oral anticoagulant (DOAC). METHODS: We retrospectively investigated patients with advanced or recurrent epithelial ovarian cancer and distal DVT diagnosed by ultrasonography who underwent chemotherapy containing bevacizumab (15 mg/kg every 3 weeks) combined with DOAC therapy. RESULTS: Bevacizumab was administered to 88 patients, including 7 patients (7.9%) receiving concomitant DOAC therapy for distal DVT. In these 7 patients, the median body mass index was 21.3 kg/m2, median D-dimer level at diagnosis of DVT was 4.3 µg/mL, and median duration of DOAC therapy was 8 months. Adverse events during DOAC therapy were grade 1 epistaxis and grade 1 hemorrhoidal bleeding in one patient each. DVT resolved in four patients and was unchanged in three patients, with no central progression or secondary thromboembolism. CONCLUSION: In ovarian cancer patients who have distal DVT, bevacizumab can possibly be administered safely when combined with a DOAC. To confirm this finding, further investigation on a larger scale will be required.

Relationship of patient background with macro- and microvascular complications: a 2-year post-marketing surveillance of vildagliptin in nearly 20,000 Japanese diabetic patients.

BACKGROUND: Vildagliptin is indicated for type 2 diabetes mellitus (T2DM); however, the onset and exacerbation of diabetic complications in Japanese T2DM patients treated with vildagliptin is unknown. RESEARCH DESIGN AND METHODS: This 2-year post-marketing surveillance (PMS) assessed the real-world safety and efficacy of vildagliptin therapy in 19,218 Japanese T2DM patients. The relationship between the incidence of macro- and microvascular complications with patient characteristics and changes in glycemic control (HbA1c) were evaluated. RESULTS: The incidences of macro- and microvascular diseases were 1.14% and 3.09%, respectively. Patients with HbA1c ≥8.4% had a higher odds ratio (OR) for micro- and macrovascular disease (OR: 2.02 and 1.90) compared with patients with HbA1c <6.9%. Patient characteristics (OR, 95% CI) associated with macrovascular disease were age (1.04, 1.01-1.07) and a history of macrovascular disease (3.38, 1.98-5.75). Microvascular disease was associated with a final HbA1c level ≥7.0% (1.48, 1.11-1.98) and previous diabetic nephropathy (1.42, 1.05-1.93). The mean (SD) HbA1c decreased from 7.89% (1.46%) to 7.05% (0.99%) after 24 months. CONCLUSIONS: Vildagliptin elicited no increases/exacerbations of diabetic complications; this PMS suggested that the incidence of diabetic complications tends to be low in subjects with good HbA1c control.

Bilateral thigh compartment syndromes from extended sitting with forward bending.

Alcohol consumption and subsequent sleeping in unusual positions often causes compression neuropathies. In this case, we experienced a unique case of bilateral leg palsy after sleeping in a forward bending position that was photographed by his colleague. We expected that prolonged blockage of the circulation of the femoral arteries resulted in bilateral thigh compartment syndromes (TCSs), leading to sciatic nerve damage. The muscle MRI and needle EMG support this hypothesis. A couple of similar cases have been reported, but the causes of TCS was undetermined due to lack of medical history. This case illustrates that atraumatic compartment syndrome with sciatic nerve palsy can be occurred by prolonged unusual positions.

Human EP3(I) prostanoid receptor induces VEGF and VEGF receptor-1 mRNA expression.

A critical event in tumor development is the formation of new blood vessels to provide oxygen, nutrients and growth factors to the rapidly growing cancer cells. This process of angiogenesis is complex, however, it is well established that vascular endothelial growth factor (VEGF)-mediated signaling is an important early event. Knockout mice studies have implicated the EP3 receptor in tumor development and angiogenesis; however, the signaling mechanism involved with this effect is unclear. We now show that stimulation of the EP3(I) isoform of the human EP3 receptor with prostaglandin E(2) increases the mRNA expression of both VEGF and its cognate receptor VEGF receptor-1 (VEGFR-1). These inductions by the EP3(I) receptor involve the sequential activation of phosphatidylinositol 3-kinase and the extracellular signal-regulated kinases. Up-regulation of VEGF and VEGFR-1 mRNA by the human EP3(I) receptor has not been previously reported and further strengthen the role of this receptor in tumor-associated angiogenesis.

Vanadate-induced activation of cytosolic phospholipase A2alpha in L929 cells: Roles of tyrosine kinase, protein kinase C, and extracellular signal-regulated kinase.

Orthovanadate (Na3VO4), which acts as an inhibitor of protein tyrosine phosphatases, has a various pharmacological effects including the release of arachidonic acid (AA) from cells. We investigated roles of alpha-type cytosolic phospholipase A2 (cPLA2alpha), Src family kinases (Src) and protein kinase C (PKC) in the release of AA induced by Na3VO4 from a murine fibroblast cell line, L929. C12 cells, a variant of L929 that lacks expression of cPLA2alpha, were used along with a clone of C12 cells that are stably expressing cPLA2alpha (C12-cPLA2alpha cells). In the presence of a Ca2+ ionophore (10 microM A23187), 5 and 10mM Na3VO4 synergistically stimulated AA release from L929 and C12-cPLA2alpha cells, and to a much lesser extent from control C12 cells. The release of AA by Na3VO4/A23187 was inhibited by a selective cPLA2alpha inhibitor (3 microM pyrrophenone). The release of AA by Na3VO4/A23187 was significantly inhibited by a PKC inhibitor (10 microM GF109203X), in PKC-depleted cells, by a Src inhibitor (2 microM PP2) and by an inhibitor of extracellular signal-regulated kinase 1/2 (ERK1/2) kinase (10 microM U0126). The phosphorylation of ERK1/2 was stimulated by Na3VO4, and the response was significantly decreased by inhibitors of Src, PKC and ERK1/2 kinase. Our data show that Na3VO4 stimulates AA release largely via cPLA2alpha activation in Ca2+-dependent manner, and the cross-talk between Src and PKC and the ERK-dependent pathways are involved in Na3VO4-induced AA release from L929 cells.

Hydrogen peroxide-induced arachidonic acid release in L929 cells; roles of Src, protein kinase C and cytosolic phospholipase A2alpha.

Hydrogen peroxide (H(2)O(2)) stimulates the release of arachidonic acid from cells, but the signaling mechanism(s) involved remains to be elucidated. We investigated the roles of alpha-type cytosolic phospholipase A(2) (cPLA(2)alpha), Src family kinases (Src) and protein kinase C (PKC) in the release of arachidonic acid from L929 cells (a murine fibroblast cell line), C12 cells (a variant of L929 that lacks cPLA(2)alpha) and a stable clone of C12 cells expressing cPLA(2)alpha (C12-cPLA(2)alpha cells). In the presence of 10 muM A23187, 100 nM phorbol myristate acetate (PMA) and 1 mM H(2)O(2) synergistically stimulated arachidonic acid release from L929 cells and C12-cPLA(2)alpha cells, and to a much lesser extent from C12 cells. The reagents alone and co-treatment with PMA and H(2)O(2) without A23187 had marginal effects. No arachidonic acid was released by PMA/A23187 or H(2)O(2)/A23187 in CaCl(2)-free buffer and the release was inhibited by a selective cPLA(2)alpha inhibitor (3 microM pyrrophenone). Addition of 10 microM H(2)O(2), which did not stimulate arachidonic acid release with A23187, enhanced the response to PMA/A23187. The release induced by PMA/A23187 and by H(2)O(2)/A23187 was significantly inhibited by a PKC inhibitor (10 microM GF109203X) and in PKC-depleted cells, and by a Src inhibitor (2 microM PP2). The phosphorylation of extracellular signal-regulated kinase 1/2 induced by PMA/A23187 and H(2)O(2)/A23187 was significantly decreased by inhibitors of PKC and Src. These findings suggest that H(2)O(2) with Ca(2+) stimulates arachidonic acid release via cPLA(2)alpha in a Src- and PKC-dependent manner in L929 cells. The role of cross-talk between Src and PKC in arachidonic acid release is discussed.

Clinical significance of systematic retroperitoneal lymphadenectomy during interval debulking surgery in advanced ovarian cancer patients.

OBJECTIVE: To investigate the clinical significance of systematic retroperitoneal lymphadenectomy during interval debulking surgery (IDS) in advanced epithelial ovarian cancer (EOC) patients. METHODS: We retrospectively reviewed the medical records of 124 advanced EOC patients and analyzed the details of neoadjuvant chemotherapy (NACT), IDS, postoperative treatment, and prognoses. RESULTS: Following IDS, 98 patients had no gross residual disease (NGRD), 15 had residual disease sized <1 cm (optimal), and 11 had residual disease sized ≥1 cm (suboptimal). Two-year overall survival (OS) and progression-free survival (PFS) rates were 88.8% and 39.8% in the NGRD group, 40.0% and 13.3% in the optimal group (p<0.001 vs. NGRD for both), and 36.3% and 0% in the suboptimal group, respectively. Five-year OS and 2-year PFS rates were 62% and 56.1% in the lymph node-negative (LN-) group and 26.2% and 24.5% in the lymph node-positive (LN+) group (p=0.0033 and p=0.0024 vs. LN-, respectively). Furthermore, survival in the LN+ group, despite surgical removal of positive nodes, was the same as that in the unknown LN status group, in which lymphadenectomy was not performed (p=0.616 and p=0.895, respectively). Multivariate analysis identified gross residual tumor during IDS (hazard ratio, 3.68; 95% confidence interval, 1.31 to 10.33 vs. NGRD) as the only independent predictor of poor OS. CONCLUSION: NGRD after IDS improved prognosis in advanced EOC patients treated with NACT-IDS. However, while systematic retroperitoneal lymphadenectomy during IDS may predict outcome, it does not confer therapeutic benefits.

A Novel Method for Rearing Zebrafish by Using Freshwater Rotifers (Brachionus calyciflorus).

The zebrafish (Danio rerio) has become a powerful model organism for studying developmental processes and genetic diseases. However, there remain several problems in previous rearing methods. In this study, we demonstrate a novel method for rearing zebrafish larvae by using a new first food, freshwater rotifers (Brachionus calyciflorus). Feeding experiments indicated that freshwater rotifers are suitable as the first food for newly hatched larval fish. In addition, we revisited and improved a feeding schedule from 5 to 40 days postfertilization. Our feeding method using freshwater rotifers accelerated larval growth. At 49 dpf, one pair out of 10 pairs successfully produced six fertilized eggs. At 56, 63, and 71 dpf, 6 out of the 10 pairs constantly produced normal embryos. Our method will improve the husbandry of the zebrafish.

Antepartum ornithine transcarbamylase deficiency.

Ornithine transcarbamylase deficiency (OTCD) is the most common type urea cycle enzyme deficiencies. This syndrome results from a deficiency of the mitochondrial enzyme ornithine transcarbamylase, which catalyzes the conversion of ornithine and carbamoyl phosphate to citrullin. Our case was a 28-year-old female diagnosed with OTCD following neurocognitive deficit during her first pregnancy. Although hyperammonemia was suspected as the cause of the patient's mental changes, there was no evidence of chronic liver disease. Plasma amino acid and urine organic acid analysis revealed OTCD. After combined modality treatment with arginine, sodium benzoate and hemodialysis, the patient's plasma ammonia level stabilized and her mental status returned to normal. At last she recovered without any damage left.

Effect of semen characteristics on pregnancy rate following intrauterine insemination.

OBJECTIVE: To assess the effects of semen characteristics on the success of intrauterine insemination (IUI). DESIGN: A retrospective study. SETTINGS: The Department of Obstetrics and Gynecology, Tokushima University Hospital, Japan. PATIENTS: Between 2004 and 2008, 1,177 IUI cycles in 283 couples were studied. INTERVENTION: IUI cycles were preceded with ovarian stimulation. MAIN OUTCOME MEASURE: Clinical pregnancy. RESULT: A total of 82 clinical pregnancies were obtained (7.0% pregnancy rate per cycle, 28.9% per case). Their subsequent outcomes of pregnancies were 18 miscarriages (21.9%), 2 ectopic pregnancies (2.4%) and 60 live births (73.2%). Of the 82 clinical pregnancies, 2 were twin pregnancies (2.4%). There was no triple or higher order multiple pregnancies. At the end of the sixth cycle, 73 clinical pregnancies had been achieved (89.0%). After diagnostic laparoscopy, the pregnancy rate per cycle for patients ≤ 35 years age was 18%, which is significantly higher than that of patients >35 years of age. Pregnancies occurred up to the fifth cycle after laparoscopy. The pregnancy rate (PR) per cycle was significantly higher in cases of sperm movement rates more than 30% (PR 9.3%) and total motile sperm counts more than 10 × 10(6)/ml (PR 8.2%). A study comparing the washed and unwashed cases did not reveal any differences. CONCLUSION: In male sub-fertility cases of sperm parameters as motility rates ≥ 30% and motile sperm concentration ≥ 10 × 10(6)/ml, IUI could be a useful option for infertility treatment.

Expression of cytosolic phospholipase A2 alpha in murine C12 cells, a variant of L929 cells, induces arachidonic acid release in response to phorbol myristate acetate and Ca2+ ionophores, but not to tumor necrosis factor-alpha.

Tumor necrosis factor-alpha (TNFalpha)-induced cell death is regulated through the release of arachidonic acid (AA) by group IVA cytosolic phospholipase A2 (cPLA2alpha) in the murine fibroblast cell line L929. However, the signaling pathway by which TNFalpha activates cPLA2alpha remained to be solved. We examined AA release in L929 cells, in a variant of L929 (C12 cells) lacking cPLA2alpha, and in C12 cells transfected with cPLA2alpha expression vectors. In transient and stable clones of C12 cells expressing cPLA2alpha, Ca2+ ionophore A23187 and phorbol myristate acetate (PMA) stimulated AA release within 90 min, although no response to TNFalpha was observed within 6 h. These results suggest that C12 cells may lack the components necessary for TNFalpha-induced AA release, in addition to cPLA2alpha. PMA is known to stimulate AA release via phosphorylation of Ser505 in cPLA2alpha by activating extracellular signal-regulated kinases (ERK1/2). However, PMA-induced AA release from C12 cells expressing mutant cPLA2alpha S505A (mutation of Ser505 to Ala), which is not phosphorylated by ERK1/2, was similar to that from L929 cells and C12 cells expressing wild-type cPLA2alpha. The role of Ser505 phosphorylation in AA release induced by PMA is also discussed.