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Death-associated protein kinase (DAPK) 2 is a serine/threonine kinase that belongs to the DAPK family. Although it shows significant structural differences from DAPK1, the founding member of this protein family, DAPK2 is also thought to be a putative tumour suppressor. Like DAPK1, it has been implicated in programmed cell death, the regulation of autophagy and diverse developmental processes. In contrast to DAPK1, however, few mechanistic studies have been carried out on DAPK2 and the majority of these have made use of tagged DAPK2, which almost invariably leads to overexpression of the protein. As a consequence, physiological roles of this kinase are still poorly understood. Using two genetically distinct cancer cell lines as models, we have identified a new role for DAPK2 in the regulation of mitochondrial integrity. RNA interference-mediated depletion of DAPK2 leads to fundamental metabolic changes, including significantly decreased rate of oxidative phosphorylation in combination with overall destabilised mitochondrial membrane potential. This phenotype is further corroborated by an increase in the production of mitochondrial superoxide anions and increased oxidative stress. This then leads to the activation of classical stress-activated kinases such as ERK, JNK and p38, which is observed on DAPK2 genetic ablation. Interestingly, the generation of oxidative stress is further enhanced on overexpression of a kinase-dead DAPK2 mutant indicating that it is the kinase domain of DAPK2 that is important to maintain mitochondrial integrity and, by inference, for cellular metabolism.

It is thought that the time interval between the antecedent pregnancy and diagnosis of gestational trophoblastic tumours (GTTs) may influence the outcome of these patients. In this study, we investigate the significance of this time interval. Multivariate analysis was used to investigate if the time interval was of prognostic significance from our cohort of 241 high-risk patients with GTT. Subsequent cutpoint analysis was used to determine an optimal cutpoint for the interval covariate. The outcome of these patients was plotted according to the Kaplan–Meier method. The time interval was of prognostic significance on multivariate analysis. A period of greater than 2.8 years after pregnancy was found to be of most significance. The 5-year overall survival was 62.0% (95% CI: 47–76%) for greater than 2.8 years vs 94% (95% CI: 91–97%) for less than 2.8 years (P

Background Primary retroperitoneal germ cell tumours usually present as a large abdominal mass in young men. The testes are normal on examination and ultrasonography but there are usually raised serum levels of human chorionic gonadotrophin and/or a-fetoprotein. Methods Fourteen men (median age 33 years) with primary retroperitoneal germ cell tumours were treated by chemotherapy followed by surgical resection of the primary tumour and metastases via a thoracoabdominal extraperitoneal approach. Results There was minimal morbidity. The survival rate was 13 of 14 and the disease-free survival rate was 11 of 14 after a median follow-up of 15 months. Conclusion The thoracoabdominal extraperitoneal approach for the removal of retroperitoneal germ cell tumours and their metastases after chemotherapy improves tumour clearance, morbidity and recovery time compared with the transperitoneal anterior approach.

The standard management of placental site trophoblastic tumours (PSTTs) is a radical hysterectomy with pelvic lymph node sampling. We present five cases to demonstrate a modified Strassman procedure (MSP), which is an alternative fertility-sparing technique. Each had a presumed solitary uterine PSTT. Following surgery, one patient remained in remission with her fertility intact. The other four underwent a completion hysterectomy because of incomplete excision of the disease. No residual disease was later found in two of these four uteri. This treatment should only be offered after extensive counselling. We intend to investigate the use of intraoperative frozen section analysis with cold-knife dissection in future.

To determine the parental origin of the genome in the molar pregnancies of two familes with familial recurrent hydatidiform mole (FRHM) and to investigate whether the gene responsible for FRHM is likely to be located within the 19q13.4 region in these familes.The features of complete hydatidiform mole (CHM) were confirmed by pathological examination. DNA of CHM was prepared from sections of formalin-fixed paraffin-embedded blocks of molar tissue following laser capture microdissection. The polymerace chain reaction was used to amplify microsatellite polymorphisms in DNA from the patients, their husbands and the captured molar tissue. Parental contributions to the molar tissue were determined using ABI 310 GeneScan software. Genotyping and haplotype analysis of the candidate region on 19q13.4 was performed for members of both families using 25 microsatellite markers.One CHM from each family was identified as a biparental complete hydatidiform mole. All patients were heterozygous for most of the markers in the chromosome region of interest. In addition the two affected sisters in one of the families had different genotypes for the 19q13.4 region, suggesting that mutations in a different locus might be responsible for the disorder in this family.The location of the gene responsible for FRHM is unlikely to be located in the 19q13.4 chromosomal region in these two families suggesting that FRHM shows genetic heterogeneity.

To determine pregnancy outcome, including the rate of repeat molar pregnancy, following histologically confirmed complete or partial hydatidiform mole.Retrospective review of a large supraregional database of registrations for gestational trophoblastic disease.Supraregional Trophoblastic Disease Unit, London.Women with pregnancies affected by complete or partial hydatidiform mole registered between 1992 and 1998.All patients with a diagnosis of histologically confirmed complete or partial hydatidiform mole were identified and data on subsequent pregnancies compared between groups using comparison of proportion test.Pregnancy outcome by partial or complete mole subtype, with particular regard to risk of subsequent molar pregnancy.Of 2578 complete moles, the subsequent pregnancy was affected by hydatidiform mole in 27 (1.9%) cases, including 22 (81%) complete moles and 5 (19%) partial moles. Of 2627 partial moles, the subsequent pregnancy was also molar in 25 (1.7%) cases, including 17 (68%) partial moles and 8 (32%) complete moles. Overall recurrence risk for molar pregnancy was 1.8% (1 in 55), or a 20-fold increase compared with the background risk. Of 27 cases with repeat complete moles, three had further complete moles, suggesting the recurrence risk following two previous complete moles is approximately 10%. There were no other significant differences in pregnancy outcome between cases with previous complete or partial hydatidiform mole and that expected in an unselected obstetric population.Women having a pregnancy affected by a histologically confirmed complete or partial hydatidiform mole may be counselled that the risk of repeat mole in a subsequent pregnancy is about 1 in 60 and if this were to occur, the majority of cases will be of the same type of mole as the preceding pregnancy. However,98% of women who become pregnant following a molar conception will not have a further hydatidiform mole and these pregnancies are at no increased risk of other obstetric complications.

Nordihydroguaiaretic acid (NDGA) 1 is a constituent of the creosote bush Larrea divaricata and is well known to be a selective inhibitor of lipoxygenases. NDGA can also inhibit the platelet derived growth factor receptor and the protein kinase C intracellular signalling family, which both play an important role in proliferation and survival of cancers. Moreover, NDGA induces apoptosis in tumour xenografts. Although it is likely to have several targets of action, NDGA is well tolerated in animals. These encouraging results have prompted interest in the compound for clinical study. However, high concentrations of NDGA are required for efficacy and more potent analogues are required. We have synthesized five analogues of NDGA with different lengths of carbon bridge between the two catechol moieties in order to establish the spacing required for optimum anticancer effect and to compare their activities with NDGA. In order to ascertain if the catechol moieties are essential for anticancer activity, we prepared five analogues of NDGA containing only one hydroxyl group on each aromatic ring. NDGA 1, its racemic form 2, the catechol derivatives 5, 6 with five or six carbon atom bridges and the phenol analogues 8-11 with bridges of three to six carbon atoms all showed similar activity, with IC50 values of approximately 3-5 microM against the H-69 small cell lung cancer cell line. Analogues with shorter (3) or longer bridges (7, 12) were much less active. The most potent analogue was the biscatechol with a four-carbon bridge 4 which was10 times more active than NDGA and therefore represents a new lead compound in this area. Surprisingly, the tetramethyl ether 14 of this compound was slightly more active than NDGA, but the trihydroxy analogue 13 was less active than NDGA. The conformationally restricted analogue 15 was also less active than NDGA. In summary, simplification of the structure of NDGA by removal of the methyl groups has produced a new lead compound 4, which is10 times more potent than NDGA as a proliferative inhibitor of H-69 small cell lung cancer cells.

To describe the clinical and histological features of a series of cases of placentas originally diagnosed as partial moles in which the final diagnosis was that of placental stem villous hydrops, mesenchymal dysplasia or Beckwith-Wiedemann syndrome.We searched a computerized database containing cases of suspected or proven trophoblastic disease examined at the Trophoblastic Disease Unit at Charing Cross Hospital, London, to identify cases in which stem vessel hydrops was present without other histological features of partial mole. For each case, histological sections were examined and the histological features present recorded. There were 15 cases identified. Placental weight was above the 95th centile of the normal for gestation in all cases in which this information was documented. In an additional five cases the placenta was described as 'large'. All cases had marked stem vessel hydropic change with cyst formation and in the majority of cases some terminal villous hydrops was also present. In 13 of the 15 cases there was marked aneurysmal dilatation of stem villous vessels. Nine had focal chorioangiomatoid change and in four of these extramedullary haematopoiesis was focally present in these areas. No excessive trophoblast proliferation was noted in any case and no trophoblastic inclusions typical of partial mole were identified.This study has identified cases of stem villous hydrops, mesenchymal dysplasia or Beckwith-Wiedemann spectrum in pregnancies initially diagnosed as partial hydatidiform mole in the second half of pregnancy and has highlighted the need for detailed pathological examination and clinicopathological correlation in all such cases.

Between 1979 and 1996 303 men with stage I testicular germ cell tumours (120 seminoma and 183 non-seminomatous germ cell tumours (NSGCT)) were enrolled onto a programme of surveillance. In our institutions the frequency of computed tomography (CT) scans is reduced compared with other centres. For all 303 men, the median follow-up is 5.1 years (range: 0.1-21.7 years) and there have only been 3 deaths (1 from disease, 1 from neutropenic sepsis and 1 from secondary leukaemia). 52/183 (28%) patients with NSGCT and 18/120 (15%) patients with seminoma have relapsed. The relapse-free survival at 5 years is 82% for seminoma and 69% for NSGCT (Logrank P=0.004). All men who relapsed, except 1 man with NSGCT, were in the International Germ Cell Cancer Collaborative Group good or intermediate prognosis group at relapse. Half of the seminoma relapses presented with symptoms and 31% of the NSGCT relapses. The remaining relapses were detected serologically or radiologically by the surveillance programme. 5 men (2%) on surveillance, 3 with initial diagnosis of seminoma and 2 with NSGCT, have developed second contralateral testis tumours (all stage I seminomas). In a well motivated centre a policy of surveillance for stage I testicular germ cell tumours (both NSGCT and seminoma) is associated with a low mortality rate (3/303, 1%) and may have the advantage of sparing overtreatment with potentially toxic therapies in this group of young men.

Hypoglycemia is a condition commonly seen in the emergency department and is usually caused by insulin or sulfonylurea therapy for diabetes mellitus. Tumor-induced hypoglycemia occurs more rarely and can involve several mechanisms, according to whether the tumor is of pancreatic islet-cell origin or of extrapancreatic, non–islet-cell origin.1 The pancreatic islet beta-cell tumors (insulinomas) cause hypoglycemia by producing excessive insulin. In contrast, non–islet-cell tumors can cause hypoglycemia in any of several ways. They include release by the tumor of insulin-like growth factor II or its high-molecular-weight precursor,2–4 multiple metastases to the liver, massive tumor burden, or rarely, the production of . . .

To analyze the causes of therapeutic success and failure in the management of patients with high-risk gestational trophoblastic tumors (GTTs).Analysis of 272 consecutive high-risk patients treated at the trophoblastic disease center at the Charing Cross Hospital between 1979 and 1995.EMA (etoposide, methotrexate, actinomycin D)/CO (cyclophosphamide, vincristine) chemotherapy is our treatment of choice for patients with high-risk GTT. In 272 consecutive patients the cumulative five-year survival was 86.2% (95% confidence interval, 81.9-90.5%). No deaths occurred from GTT more than two years after the start of treatment. In patients whose disease became resistant to EMA/CO or relapsed after receiving EMA/CO, the majority (70%) could be salvaged with further chemotherapy (usually with the EP (etoposide, cisplatin)/EMA chemotherapy with or without surgery. Multivariate analysis identified the following adverse prognostic factors: presence of liver metastases (P.0001), prolonged interval from antecedent pregnancy (P.0001), presence of brain metastases (P = .0008) and term delivery of antecedent pregnancy (P = .045). Intensive chemotherapy for treating high-risk GTT carries a small risk of inducing second malignancies, and two patients developed acute myeloid leukemia, 2 cervical malignancy and 1 gastric adenocarcinoma after receiving EMA/CO chemotherapy.EMA/CO is an effective and well-tolerated regimen for high-risk GTT. Salvage chemotherapy with EP/EMA is effective in the majority of patients whose disease is resistant to EMA/CO and should be combined with surgery when the dominant site of resistant disease is known. Major adverse prognostic variables have been identified, and patients with combinations of these factors should be considered for innovative therapeutic approaches from the outset.

To evaluate the efficacy and safety of extraperitoneal surgical approaches for the removal of residual masses of metastatic germ cell tumours in men after chemotherapy.A series of 75 men (median age 32 years) with metastatic germ cell tumours of testicular (n = 63) or extragonadal (n = 12) origin, who had been treated with an intensive course of platinum-based chemotherapy, were found to have residual tumour masses. Extraperitoneal surgical approaches were used on 80 occasions to excise these masses. A thoraco-abdominal extraperitoneal approach (n = 71) was used for large masses and those with intrathoracic metastases while smaller retroperitoneal masses were removed through 12th rib (n = 5) or Rutherford-Morrison (n = 4) extraperitoneal approaches.Complete macroscopic clearance of residual masses within the thorax and retroperitoneum was achieved in all cases. The median blood loss was 0.8 L and the median in-patient stay was 7 days. Complications included chest infection in four cases. Two patients died about 4 weeks after surgery, one from septic pericarditis and another after an epileptic fit secondary to brain metastases. Eleven patients have developed tumour recurrence, five of whom have died from disseminated disease. Hence the survival rate and disease-free survival rate are 91% and 83%, respectively, with a median follow-up of 22 months.The thoraco-abdominal extraperitoneal surgical approach for retroperitoneal lymph node dissection after chemotherapy for testicular cancer is safe and has some advantages over anterior approaches, allowing synchronous removal of intrathoracic disease, improved access to nodes above and behind the renal vessels and more rapid post-operative recovery.

Gestational trophoblastic disease (GTD) forms a spectrum of illness from the borderline malignancy of hydatidiform mole to the highly aggressive behaviour of choriocarcinoma. In the past, many women have died from this group of disorders. However, during the last 45 years highly effective chemotherapy regimens have been developed which can be appropriately tailored to the individual patient's risk of becoming resistant to the treatment. As a result, the management of GTD is one of the modern success stories in oncology. Today, with an integrated approach to management few women die from their trophoblastic tumours.

[D-Arg1,D-Trp5,7,9,Leu11]Substance P (SP) was identified out of a panel of novel SP analogues as the most potent inhibitor of small cell lung cancer (SCLC) cell growth. This analogue inhibited proliferation of H-510 and H-69 SCLC cells in liquid culture and in semisolid media (IC50, 5 microM). Colony formation stimulated by multiple neuropeptides, including vasopressin and bradykinin, was also blocked by [D-Arg1,D-Trp5,7,9,Leu11]SP. This new SP analogue inhibited vasopressin- or bradykinin-induced Ca2+ mobilization and mitogen-activated protein kinase activation. Administration of [D-Arg1,D-Trp5,7,9,Leu11]SP inhibited the growth of an H-69 xenograft in nude mice. Our results support the hypothesis that SP analogue broad-spectrum neuropeptide antagonists could be of therapeutic value in SCLC.

Addition of guanosine 5'-3-O-(thio)triphosphate (GTP gamma S) to streptolysin O-permeabilized Swiss 3T3 cells induced tyrosine phosphorylation of M(r) 110,000-130,000 and 70,000-80,000 bands. Specifically, GTP gamma S stimulated tyrosine phosphorylation of both focal adhesion kinase (p125FAK) and paxillin. GTP gamma S induced tyrosine phosphorylation was dose-dependent (EC50 of 2.5 microM) and reached maximum levels after 1.5 min for the M(r) 110,000-130,000 band and 2 min for the M(r) 70,000-80,000 paxillin band. Guanosine 5'-O-(2-thiodiphosphate) inhibited GTP gamma S-induced tyrosine phosphorylation with an IC50 of 100 microM. Protein kinase C did not mediate GTP gamma S-induced tyrosine phosphorylation. Varying the Ca2+ concentration from 0 to 6 microM did not increase tyrosine phosphorylation above basal levels and did not affect the ability of GTP gamma S to induce tyrosine phosphorylation. GTP gamma S was able to stimulate tyrosine phosphorylation in the presence of nanomolar concentrations of Mg2+. Furthermore, 30 microM AlF4- only weakly induced tyrosine phosphorylation in permeabilized cells. Pretreatment with the Clostridium botulinum C3 exoenzyme which inactivates p21rho, markedly reduced the ability of GTP gamma S to stimulate tyrosine phosphorylation of M(r) 110,000-130,000 and 70,000-80,000 bands including p125FAK and paxillin in permeabilized Swiss 3T3 cells. Furthermore, a peptide of p21rho (p21rho17-44) inhibited GTP gamma S-induced tyrosine phosphorylation in a dose-dependent manner (IC50 1 microM). This peptide also inhibited tyrosine phosphorylation of p125FAK and paxillin. In contrast, 20 microM p21ras17-44 peptide failed to inhibit GTP gamma S-induced tyrosine phosphorylation. Using permeabilized cells, our findings demonstrate that GTP gamma S stimulates tyrosine phosphorylation of p125FAK and paxillin and that a functional p21rho is implicated in this process.

Serum stimulates both Ca2+ mobilization and colony growth of many small cell lung cancer (SCLC) cell lines, but the factors involved remain unknown. We demonstrate that 1-oleoyl-lysophosphatidic acid (LPA), like serum, induced a dose-dependent increase in intracellular Ca2+ in the H-510, H-345, and H-69 SCLC cell lines with half maximal concentrations of 18 nM, 22 nM, and 20 nM, respectively. Two lines of evidence revealed that LPA was the major factor in serum responsible for mobilizing Ca2+ in these SCLC cell lines: (a) both LPA and serum exhibited cross desensitization in the Ca2+ mobilization assay; and (b) phospholipase B pretreatment of either LPA or serum prevented the ability of these agents to stimulate Ca2+ mobilization. In marked contrast, LPA at concentrations between 2 nM and 20 microM, unlike serum, failed to stimulate colony formation. Furthermore, phospholipase B treatment of serum did not inhibit serum-induced colony formation. We therefore searched for growth factors which could induce colony growth through a Ca(2+)-independent pathway. We found that both human recombinant hepatocyte growth factor and stem cell growth factor increased colony growth, but failed to stimulate an increase in intracellular Ca2+ in the H-510, H-345, and H-69 SCLC cell lines. Our results indicate that LPA-depleted serum, hepatocyte growth factor, and stem cell growth factor stimulate colony formation in SCLC cells through a Ca(2+)-independent pathway.