Coordination of apicoplast transcription in a malaria parasite by internal and host cues.

The malaria parasite Plasmodium falciparum has a nonphotosynthetic plastid called the apicoplast, which contains its own genome. Regulatory mechanisms for apicoplast gene expression remain poorly understood, despite this organelle being crucial for the parasite life cycle. Here, we identify a nuclear-encoded apicoplast RNA polymerase σ subunit (sigma factor) which, along with the α subunit, appears to mediate apicoplast transcript accumulation. This has a periodicity reminiscent of parasite circadian or developmental control. Expression of the apicoplast subunit gene, apSig, together with apicoplast transcripts, increased in the presence of the blood circadian signaling hormone melatonin. Our data suggest that the host circadian rhythm is integrated with intrinsic parasite cues to coordinate apicoplast genome transcription. This evolutionarily conserved regulatory system might be a future target for malaria treatment.

A rare case of extraluminal interstitial pregnancy treated with laparoscopic cornuotomy.

We report an extremely rare case of an extraluminal interstitial pregnancy. A 36-year-old nulliparous woman visited our hospital during the fifth week of gestation. Although no intrauterine gestational sac (GS) was identified, transabdominal ultrasonography revealed a GS-like cyst was detected in the right uterine horn. She underwent laparoscopic surgery for a suspected interstitial ectopic pregnancy. After laparoscopic cornuotomy, dye leakage was observed from the fimbria rather than the incision site. Finally, the patient was diagnosed with a right extraluminal interstitial pregnancy. Hysterosalpingography performed at three postoperative months revealed bilateral tubal passage. She conceived 7 months after surgery, with safe delivery by elective cesarean section at 38 weeks.

Human papillomavirus vaccine impact on invasive cervical cancer in Japan: Preliminary results from cancer statistics and the MINT study.

The first prophylactic vaccine against human papillomavirus (HPV) 16 and HPV18 was licensed in Japan in 2009. HPV vaccine effectiveness against high-grade cervical lesions has been demonstrated among young Japanese women, but evidence of its effects on invasive cervical cancer (ICC) is lacking. Using data from two different cancer registries, we compared recent trends of new ICC cases by age group using Poisson regression analysis. We also analyzed time trends in HPV16/18 prevalence among 1414 Japanese women aged <40 years newly diagnosed with ICC in the past decade. Based on the population-based cancer registry, the incidence of ICC among young women aged 20-29 years showed a significant decline from 3.6 to 2.8 per 100 000 women-years during 2016-2019, but no similar decline was observed for older age groups (p < 0.01). Similarly, using data from the gynecological cancer registry of the Japan Society of Obstetrics and Gynecology, the annual number of ICCs among women aged 20-29 years also decreased from 256 cases to 135 cases during 2011-2020 (p < 0.0001). Furthermore, a declining trend in HPV16/18 prevalence in ICC was observed only among women aged 20-29 years during 2017-2022 (90.5%-64.7%, p = 0.05; Cochran-Armitage trend test). This is the first report to suggest population-level effects of HPV vaccination on ICC in Japan. Although the declining trend in HPV16/18 prevalence among young women with ICC supports a causal linkage between vaccination and results from cancer registries, further studies are warranted to confirm that our findings are attributable to vaccination.

MicroRNA-152 Regulates Endometrial Serous Carcinoma Cell Motility by Suppressing Matrix Metalloproteinase 10 Expression.

MicroRNA-152 (miR-152) expression has been reported to be associated with poor prognosis in patients with endometrial serous carcinoma (ESC). However, the function of miR-152 in ESCs is not fully understood. The present study aimed to investigate the involvement of miR-152 in ESC progression. The influence of miR-152 overexpression on cell proliferation and motility was assessed by transfecting two human ESC cell lines, USPC-1 and SPAC-1-L, with a miR-152 precursor. MiR-152 overexpression increased apoptosis and inhibited the proliferation of the two ESC cell lines. Cell motility was also suppressed in both cell lines following precursor transfection. Conversely, miR-152 inhibitor transfection led to an increase in cell migration ability, suggesting the involvement of miR-152 in ESC cell motility. Results of the analysis of publicly available messenger RNA dataset indicated that high expression of matrix metalloproteinase 10 (MMP10), one of the predicted targets of miR-152 by microRNA target prediction database, was a poor prognostic factor for ESC. In vitro examination results revealed that miR-152 overexpression reduced MMP10 expression, and knockdown of MMP10 significantly reduced cell motility. This study elucidates the function of miR-152 as a tumor suppressor in ESCs. We demonstrated that miR-152 plays an important role in ESC cell motility by regulating MMP10 expression.

The efficacy and safety profile of 2-weekly dosing of bevacizumab-containing chemotherapy for platinum-resistant recurrent ovarian cancer.

BACKGROUND: Despite being widely used, to date (June 2021), the regimen of bevacizumab 10 mg/kg every 2 weeks (Q2W) combined with chemotherapy is not approved in Japan for patients with platinum-resistant recurrent ovarian cancer. In this retrospective analysis, we evaluated the usage patterns of bevacizumab administered for platinum-resistant recurrent ovarian cancer. METHODS: We obtained clinical data from 155 Japanese medical facilities between November 2013 and December 2018 via a survey. Items included the number of cases of platinum-resistant recurrent ovarian cancer treated with bevacizumab according to dosage. For regimens including bevacizumab 10 mg/kg Q2W, additional information was requested relating to concomitantly administered agents, and the efficacy and safety of the regimen. RESULTS: Of 1739 bevacizumab-containing regimens reported in 1633 patients with recurrent ovarian cancer, 264 used 10 mg/kg Q2W. The overall response rate (ORR) with this regimen was 26.1%. Response rates varied according to regimen and were particularly favorable when bevacizumab 10 mg/kg Q2W was administered with paclitaxel (ORR, 53.0%) versus liposomal doxorubicin (15.0%; P < 0.0001) and irinotecan (7.7%; P < 0.028). The most frequent Grade ≥ 3 adverse events associated with bevacizumab 10 mg/kg Q2W were neutropenia (11.7%) and hypertension (11.7%). The most frequent bevacizumab-associated Grade ≥ 3 adverse events with bevacizumab plus paclitaxel versus bevacizumab plus liposomal doxorubicin were hypertension (9.0% versus 13.9%) and proteinuria (3.0% versus 8.4%). CONCLUSIONS: Bevacizumab 10 mg/kg Q2W appears efficacious for patients with recurrent ovarian cancer, with a manageable toxicity profile. Approval of this regimen is clinically desirable for Japanese patients with ovarian cancer.

Association of gBRCA1/2 mutation locations with ovarian cancer risk in Japanese patients from the CHARLOTTE study.

Whether germline (g) breast cancer susceptibility gene (BRCA) mutations are located within or outside the ovarian cancer cluster region (OCCR) (1380-4062 bp for gBRCA1, and between 3249-5681 bp and 6645-7471 bp for gBRCA2) may influence risk variations for ovarian cancers. This ad hoc analysis of the CHARLOTTE epidemiological study in Japan assessed the distribution of gBRCA1/2 mutations in patients with newly diagnosed ovarian cancer, and investigated an association between gBRCA1/2 mutation locations and ovarian cancer risk. Differences in patient background and clinical characteristics in subgroups stratified by gBRCA1/2 mutation locations were also evaluated. We analyzed the data of 93 patients (14.7%) from the CHARLOTTE study who were positive for gBRCA1/2 mutations. After excluding 16 cases with L63X founder mutation, 28 (65.1%) of gBRCA1 mutations were within the OCCR. Of 30 gBRCA2 mutations, 15 (50.0%) were within the OCCR. Of 27 patients (one patient excluded for unknown family history) with gBRCA1 mutations located in the OCCR, 11 (40.7%) had a family history of ovarian cancer; the proportion of patients with a family history of ovarian cancer and gBRCA1 mutations outside the OCCR was lower (13.3%). Sixty percent of patients with gBRCA1 mutations outside the OCCR had a family history of breast cancer; the proportion of patients with a family history of breast cancer and gBRCA1 mutations within the OCCR was relatively lower (33.3%). Understanding the mutation locations may contribute to more accurate risk assessments of susceptible individuals and early detection of ovarian cancer among gBRCA mutation carriers.

Discovery of trypanocidal coumarins with dual inhibition of both the glycerol kinase and alternative oxidase of Trypanosoma brucei brucei.

African trypanosomiasis, sleeping sickness in humans or nagana in animals, is a potentially fatal neglected tropical disease and a threat to 65 million human lives and 100 million small and large livestock animals in sub-Saharan Africa. Available treatments for this devastating disease are few and have limited efficacy, prompting the search for new drug candidates. Simultaneous inhibition of the trypanosomal glycerol kinase (TGK) and trypanosomal alternative oxidase (TAO) is considered a validated strategy toward the development of new drugs. Our goal is to develop a TGK-specific inhibitor for coadministration with ascofuranone (AF), the most potent TAO inhibitor. Here, we report on the identification of novel compounds with inhibitory potency against TGK. Importantly, one of these compounds (compound 17) and its derivatives (17a and 17b) killed trypanosomes even in the absence of AF. Inhibition kinetics revealed that derivative 17b is a mixed-type and competitive inhibitor for TGK and TAO, respectively. Structural data revealed the molecular basis of this dual inhibitory action, which, in our opinion, will aid in the successful development of a promising drug to treat trypanosomiasis. Although the EC50 of compound 17b against trypanosome cells was 1.77 µM, it had no effect on cultured human cells, even at 50 µM.-Balogun, E. O., Inaoka, D. K., Shiba, T., Tsuge, C., May, B., Sato, T., Kido, Y., Nara, T., Aoki, T., Honma, T., Tanaka, A., Inoue, M., Matsuoka, S., Michels, P. A. M., Watanabe, Y.-I., Moore, A. L., Harada, S., Kita, K. Discovery of trypanocidal coumarins with dual inhibition of both the glycerol kinase and alternative oxidase of Trypanosoma brucei brucei.

Genetic polymorphisms in malaria vaccine candidate Plasmodium falciparum reticulocyte-binding protein homologue-5 among populations in Lagos, Nigeria.

BACKGROUND: Vaccines are the most reliable alternative to elicit sterile immunity against malaria but their development has been hindered by polymorphisms and strain-specificity in previously studied antigens. New vaccine candidates are therefore urgently needed. Highly conserved Plasmodium falciparum reticulocyte-binding protein homologue-5 (PfRH5) has been identified as a potential candidate for anti-disease vaccine development. PfRH5 is essential for erythrocyte invasion by merozoites and crucial for parasite survival. However, there is paucity of data on the extent of genetic variations on PfRH5 in field isolates of Plasmodium falciparum. This study described genetic polymorphisms at the high affinity binding polypeptides (HABPs) 36718, 36727, 36728 of PfRH5 in Nigerian isolates of P. falciparum. This study tested the hypothesis that only specific conserved B and T cell epitopes on PfRH5 HABPs are crucial for vaccine development. METHODS: One hundred and ninety-five microscopically confirmed P. falciparum samples collected in a prospective cross-sectional study of three different populations in Lagos, Nigeria. Genetic diversity and haplotype construct of Pfrh5 gene were determined using bi-directional sequencing approach. Tajima's D and the ratio of nonsynonymous vs synonymous mutations were utilized to estimate the extent of balancing and directional selection in the pfrh5 gene. RESULTS: Sequence analysis revealed three haplotypes of PfRH5 with negative Tajima's D and dN/dS value of - 1.717 and 0.011 ± 0.020, respectively. A single nucleotide polymorphism, SNP (G → A) at position 608 was observed, which resulted in a change of the amino acid cysteine at position 203 to tyrosine. Haplotype and nucleotide diversities were 0.318 ± 0.016 and 0.0046 ± 0.0001 while inter-population genetic differentiation ranged from 0.007 to 0.037. Five polypeptide variants were identified, the most frequent being KTKYH with a frequency of 51.3%. One B-cell epitope, 151 major histocompatibility complex (MHC) class II T-cell epitopes, four intrinsically unstructured regions (IURs) and six MHC class I T-cell epitopes were observed in the study. Phylogenetic analysis of the sequences showed clustering and evidence of evolutionary relationship with 3D7, PAS-2 and FCB-2 RH5 sequences. CONCLUSIONS: This study has revealed low level of genetic polymorphisms in PfRH5 antigen with B- and T-cell epitopes in intrinsically unstructured regions along the PfRH5 gene in Lagos, Nigeria. A broader investigation is however required in other parts of the country to support the possible inclusion of PfRH5 in a cross-protective multi-component vaccine.

MicroRNA Let-7c Contributes to Paclitaxel Resistance via Aurora-B in Endometrial Serous Carcinoma.

The incidence of endometrial cancer has rapidly risen over recent years. Paclitaxel, a key drug for endometrial cancer treatment, inhibits microtubule depolymerization and induces apoptosis in cancer cells. Endometrial serous carcinoma (ESC) accounts for < 10% of all endometrial carcinomas, but its aggressive nature makes it responsible for close to 40% of cancer deaths. Thus, novel therapeutic targets are required for ESC. To identify microRNAs that promote paclitaxel resistance, we established two paclitaxel-resistant cell lines from USPC1 human ESC cells by exposing paclitaxel to parental cells for 12 weeks. Paclitaxel concentrations were increased every 2 weeks, and after 12 weeks of paclitaxel exposure, two replicate paclitaxel-resistant cell lines were established (USPC1-PTSR1 and USPC1-PTXR2). The microarray analysis was performed using USPC1 cells and USPC1-PTXR1 cells, and eight candidate microRNAs were thus selected as potential mediators of paclitaxel sensitivity. Among these candidate microRNAs, let-7c precursor treatment of paclitaxel-resistant USPC1-PTXR1 cells caused the greatest increase in paclitaxel-mediated cytotoxicity. Let-7c inhibition conversely decreased paclitaxel-induced apoptosis. It is known that let-7a microRNA, a member of the let-7 family, inhibits growth of endometrial carcinoma cells targeting Aurora-B that controls progression through each phase of mitosis. We thus studied whether let-7c mediates Aurora-B expression in ESC cells. The expression levels of Aurora-B mRNA and protein were higher in USPC-PTXR1 cells compared with USPC1 cells. Let-7c inhibition increased Aurora-B expression in USPC1 cells but decreased Aurora-B expression in USPC1-PTXR1 cells. These results indicate that let-7c mediates paclitaxel resistance via inhibition of Aurora-B expression in ESC cells.

Analysis of the relapse patterns and risk factors of endometrial cancer following postoperative adjuvant chemotherapy in a phase III randomized clinical trial.

OBJECTIVE: This study was to analyze patterns and risk factors of relapse after postoperative adjuvant chemotherapy for endometrial cancer. METHODS: Among patients enrolled in a randomized phase III trial (JGOG2043) investigating the efficacy of adjuvant chemotherapy for endometrial cancer at a high risk of progression, the recurrent patients were studied. Clinical information were collected, and correlation between relapse-related factors and clinicopathological factors were analyzed. RESULTS: Among 193 patients analyzed, 50% had local relapse and 63% had distant relapse. Local relapse involved regional lymph nodes in 30%, while distant relapse involved the abdominal cavity in 42%. Imaging was used to confirm relapse in 83%, and the median disease-free interval (DFI) was 11.5 months. Factors showing a significant correlation with DFI ≤12 months were residual tumor at surgery (p < 0.01), Grade 3 histology (p < 0.01), and lymph node metastasis (p = 0.03). In contrast, treatment with paclitaxel and carboplatin showed a significant correlation with DFI >12 months (p = 0.04). The median post-relapse overall survival (RS) was 23.9 months. In multivariate analysis, CA125 ≥ 100 U/mL prior to relapse (p < 0.01), distant metastasis (p < 0.01), DFI ≤ 12 months (p = 0.02), and not performing para-aortic lymphadenectomy (p = 0.01) were independently related to poor RS. CONCLUSIONS: Relapse of endometrial cancer following adjuvant chemotherapy often occurs by 1 year after treatment, with common relapse sites of the abdominal cavity and regional lymph nodes. Among treatment-related factors, RS was correlated with DFI and para-aortic lymphadenectomy.

The first Japanese nationwide multicenter study of BRCA mutation testing in ovarian cancer: CHARacterizing the cross-sectionaL approach to Ovarian cancer geneTic TEsting of BRCA (CHARLOTTE).

INTRODUCTION: BRCA gene mutations are associated with hereditary ovarian cancer. BRCA plays a key role in genome integrity, and mutations result in an increased risk for ovarian cancer. Although various guidelines recommend BRCA testing in patients with ovarian cancer, data on germline BRCA (gBRCA) mutation frequency in ovarian cancer in Japan are scarce. OBJECTIVE: This study aimed to determine gBRCA1/2 mutations in Japanese patients with ovarian cancer, stratified by clinicopathological characteristics, and to assess patients' satisfaction with pre-test genetic counseling. METHODS: The CHARLOTTE study (CHARacterizing the cross-sectionaL approach to Ovarian cancer: geneTic TEsting of BRCA; UMIN000025597) is the first large multicenter epidemiological survey of Japanese women, aged ≥20, with newly diagnosed ovarian cancer (epithelial, primary peritoneal, or fallopian tube cancer), with histologically confirmed specimens. Patients were enrolled sequentially and underwent pre-test genetic counseling for BRCA testing. Blood samples were centrally tested for the presence or absence of known gBRCA mutations. A questionnaire was used to assess patient satisfaction with pre-test genetic counseling. RESULTS: A total of 634 patients with a mean age of 56.9 years were included. Most patients (84.2%) had epithelial ovarian cancer, and 51.1% had FIGO stage III-IV cancer. Nearly all patients (99.5%) received genetic counseling before the BRCA testing, either by an obstetrician-gynecologist (42.0%) or a clinical geneticist (42.0%). The overall prevalence of gBRCA1/2 mutations was 14.7% (93/634), with gBRCA1 mutations (9.9%) more common than gBRCA2 mutations (4.7%). High-grade serous carcinoma showed a prevalence of gBRCA mutations of 28.5%. Most patients were satisfied with pre-test counseling, irrespective of the service provider's professional position. DISCUSSION: Patients with high-grade serous carcinoma and family history of ovarian cancer had a slightly higher prevalence of gBRCA mutations, but none of the subgroups had considerably high gBRCA mutation prevalence. These data suggest that gBRCA testing should be carried out in all patients with ovarian cancer.

Diagnostic value of combination serum assay of lactate dehydrogenase, D-dimer, and C-reactive protein for uterine leiomyosarcoma.

AIM: Leiomyosarcoma is the most common type of uterine sarcoma. In some leiomyosarcoma cases, preoperative diagnosis might be difficult, and they might be treated as benign lesions. We evaluated diagnostic values of preoperative serum lactate dehydrogenase (LDH), D-dimer and C-reactive protein for differentiating leiomyosarcoma. METHODS: From 2008 to 2013, leiomyosarcoma cases in three university hospitals were enrolled. Preoperative serum LDH, D-dimer and C-reactive protein were analyzed if tested. These markers of pathologically diagnosed leiomyoma cases presumed benign (group B) and presumed malignant (group PM) were compared with those of leiomyosarcoma cases (group S). RESULTS: Groups S, PM and B had 36, 28 and 69 cases, respectively. Positive rates of LDH were 66.7%, 14.3% and 0% in groups S, PM and B, respectively. Positive rates of D-dimer and C-reactive protein were 83.3% and 64.5%, 17.9% and 10.7% and 5% and 2.9% in groups S, PM and B, respectively. Positive rates of all three markers were high in the order of leiomyosarcoma, atypical leiomyoma and typical leiomyoma. In group PM, 12 (63.2%) cases were negative for all three markers, whereas 1 (3.3%) case was negative in group S. No case was positive for all markers in group PM, whereas 41.2% leiomyosarcoma cases were positive for all markers. When all parameters were positive, specificity and positive predictive value were 100% in differentiating leiomyosarcoma from group PM. CONCLUSION: Combination of LDH, D-dimer and C-reactive protein could be useful for distinguishing leiomyosarcoma from especially degenerated or atypical leiomyoma.

Biochemical studies of membrane bound Plasmodium falciparum mitochondrial L-malate:quinone oxidoreductase, a potential drug target.

Plasmodium falciparum is an apicomplexan parasite that causes the most severe malaria in humans. Due to a lack of effective vaccines and emerging of drug resistance parasites, development of drugs with novel mechanisms of action and few side effects are imperative. To this end, ideal drug targets are those essential to parasite viability as well as absent in their mammalian hosts. The mitochondrial electron transport chain (ETC) of P. falciparum is one source of such potential targets because enzymes, such as L-malate:quinone oxidoreductase (PfMQO), in this pathway are absent humans. PfMQO catalyzes the oxidation of L-malate to oxaloacetate and the simultaneous reduction of ubiquinone to ubiquinol. It is a membrane protein, involved in three pathways (ETC, the tricarboxylic acid cycle and the fumarate cycle) and has been shown to be essential for parasite survival, at least, in the intra-erythrocytic asexual stage. These findings indicate that PfMQO would be a valuable drug target for development of antimalarial with novel mechanism of action. Up to this point in time, difficulty in producing active recombinant mitochondrial MQO has hampered biochemical characterization and targeted drug discovery with MQO. Here we report for the first time recombinant PfMQO overexpressed in bacterial membrane and the first biochemical study. Furthermore, about 113 compounds, consisting of ubiquinone binding site inhibitors and antiparasitic agents, were screened resulting in the discovery of ferulenol as a potent PfMQO inhibitor. Finally, ferulenol was shown to inhibit parasite growth and showed strong synergism in combination with atovaquone, a well-described anti-malarial and bc1 complex inhibitor.

Clinicopathologic features and BRCA mutations in primary fallopian tube cancer in Japanese women.

OBJECTIVE: The present study aimed to clarify the clinicopathological features, including the level of p53 protein expression and BRCA mutations, of primary fallopian tube cancer (PFTC) in Japanese women. METHODS: A multicenter clinical survey was conducted at three Japanese institutions. Clinical data in patients with PFTC between 1998 and 2016 were collected. Immunohistochemical staining of p53 and BRCA mutation analysis by exome sequence using paraffin-embedded surgical resected specimens were performed. RESULTS: A total of 40 patients with PFTC were enrolled in the study. The median age was 58 years (range: 38-78 years); 31 patients were menopausal. Thirty-four (85.0%) patients were diagnosed with serous adenocarcinoma (high grade, 33; low grade, 1). PFTC was classified into ampulla type, fimbriae type and undeterminable type by tumor-occupying lesion; ampulla type and fimbriae type occurred with the same frequency. Among 30 patients with high-grade serous adenocarcinoma, 6 patients showed germline mutations of BRCA1 (stop-gain 4 and frameshift deletion 2) and 2 patients showed germline mutation of BRCA2 (stop-gain 1 and frameshift deletion 1). However, only 1 patient had familial history of breast or ovarian cancer. Patients with BRCA mutations in the germline were frequently observed in ampulla type and FIGO stage I/II cancers, but no significant difference in the frequency of p53 overexpression and overall survival was observed. CONCLUSIONS: Among Japanese patients with PFTC, 26.7% presented with BRCA mutations in the germline. Additionally, p53 was important for the carcinogenesis in fallopian tubes, independent of the specific BRCA mutation.

Duplication of Drosophila melanogaster mitochondrial EF-Tu: pre-adaptation to T-arm truncation and exclusion of bulky aminoacyl residues.

Translation elongation factor Tu (EF-Tu) delivers aminoacyl-tRNA (aa-tRNA) to ribosomes in protein synthesis. EF-Tu generally recognizes aminoacyl moieties and acceptor- and T-stems of aa-tRNAs. However, nematode mitochondrial (mt) tRNAs frequently lack all or part of the T-arm that is recognized by canonical EF-Tu. We previously reported that two distinct EF-Tu species, EF-Tu1 and EF-Tu2, respectively, recognize mt tRNAs lacking T-arms and D-arms in the mitochondria of the chromadorean nematode Caenorhabditis elegansC. elegans EF-Tu2 specifically recognizes the seryl moiety of serylated D-armless tRNAs. Mitochondria of the enoplean nematode Trichinella possess three structural types of tRNAs: T-armless tRNAs, D-armless tRNAs, and cloverleaf tRNAs with a short T-arm. Trichinella mt EF-Tu1 binds to all three types and EF-Tu2 binds only to D-armless Ser-tRNAs, showing an evolutionary intermediate state from canonical EF-Tu to chromadorean nematode (e.g. C. elegans) EF-Tu species. We report here that two EF-Tu species also participate in Drosophila melanogaster mitochondria. Both D. melanogaster EF-Tu1 and EF-Tu2 bound to cloverleaf and D-armless tRNAs. D. melanogaster EF-Tu1 has the ability to recognize T-armless tRNAs that do not evidently exist in D. melanogaster mitochondria, but do exist in related arthropod species. In addition, D. melanogaster EF-Tu2 preferentially bound to aa-tRNAs carrying small amino acids, but not to aa-tRNAs carrying bulky amino acids. These results suggest that the Drosophila mt translation system could be another intermediate state between the canonical and nematode mitochondria-type translation systems.

Expression, purification, and crystallization of type 1 isocitrate dehydrogenase from Trypanosoma brucei brucei.

Isocitrate dehydrogenases (IDHs) are metabolic enzymes that catalyze the oxidative decarboxylation of isocitrate to α-ketoglutarate. Depending on the electron acceptor and subcellular localization, these enzymes are classified as NADP+-dependent IDH1 in the cytosol or peroxisomes, NADP+-dependent IDH2 and NAD+-dependent IDH3 in mitochondria. Trypanosoma brucei is a protozoan parasite that causes African sleeping sickness in humans and Nagana disease in animals. Here, for the first time, a putative glycosomal T. brucei type 1 IDH (TbIDH1) was expressed in Escherichia coli and purified for crystallographic study. Surprisingly, the putative NADP+-dependent TbIDH1 has higher activity with NAD+ compared with NADP+ as electron acceptor, a unique characteristic among known eukaryotic IDHs which encouraged us to crystallize TbIDH1 for future biochemical and structural studies. Methods of expression and purification of large amounts of recombinant TbIDH1 with improved solubility to facilitate protein crystallization are presented.

Glycerol kinase of African trypanosomes possesses an intrinsic phosphatase activity.

BACKGROUND: In general, glycerol kinases (GKs) are transferases that catalyze phospho group transfer from ATP to glycerol, and the mechanism was suggested to be random bi-bi. The reverse reaction i.e. phospho transfer from glycerol 3-phosphate (G3P) to ADP is only physiologically feasible by the African trypanosome GK. In contrast to other GKs the mechanism of Trypanosoma brucei gambiense glycerol kinase (TbgGK) was shown to be in an ordered fashion, and proceeding via autophosphorylation. From the unique reaction mechanism of TbgGK, we envisaged its potential to possess phosphatase activity in addition to being a kinase. METHODS: Our hypothesis was tested by spectrophotometric and LC-MS/MS analyses using paranitrophenyl phosphate (pNPP) and TbgGK's natural substrate, G3P respectively. Furthermore, protein X-ray crystallography and site-directed mutagenesis were performed to examine pNPP binding, catalytic residues, and the possible reaction mechanism. RESULTS: In addition to its widely known and expected phosphotransferase (class II) activity, TbgGK can efficiently facilitate the hydrolytic cleavage of phosphoric anhydride bonds (a class III property). This phosphatase activity followed the classical Michaelis-Menten pattern and was competitively inhibited by ADP and G3P, suggesting a common catalytic site for both activities (phosphatase and kinase). The structure of the TGK-pNPP complex, and structure-guided mutagenesis implicated T276 to be important for the catalysis. Remarkably, we captured a crystallographic molecular snapshot of the phosphorylated T276 reaction intermediate. CONCLUSION: We conclude that TbgGK has both kinase and phosphatase activities. GENERAL SIGNIFICANCE: This is the first report on a bifunctional kinase/phosphatase enzyme among members of the sugar kinase family.

Current Status of Uterine Leiomyosarcoma in the Tohoku Region: Results of the Tohoku Translational Center Development Network Survey.

BACKGROUND: To prepare for a future clinical trial for improving the long-term prognosis of patients with uterine leiomyosarcoma (ULMS), we conducted a multi-institutional survey in the Tohoku region of Japan. METHODS: We conducted a retrospective cohort study between 2011 and 2014 in member institutions of the Tohoku Translational Research Center Development Network. RESULTS: A total of 53 patients with ULMS were registered in 31 institutions for the present survey. The median patient age was 56 years, 67.9% of the patients were postmenopausal, 88.7% had a performance status of 0 or 1, and only 6 patients (11.3%) showed preoperative evidence of malignancy. Although retroperitoneal lymphadenectomy was performed in only 26.4% of patients, 64.2% patients were identified as having FIGO stage 1 disease; 73.6% were eligible to undergo complete surgery. Among 36 patients who were treated with postoperative chemotherapy, 28 (77.8%) received docetaxel and gemcitabine combination therapy. The most frequent recurrence site was the lungs, and the median progression-free survival of all enrolled patients was 11.7 months. However, the median progression-free survival and the median overall survival in patients with stages III and IV disease were 3.4 and 11.4 months, respectively. CONCLUSION: Although ULMS was associated with a high rate of complete or optimal surgery, the long-term prognosis was poor. Effective postoperative therapy should be developed to improve the long-term prognosis of patients with ULMS.

Primary osteosarcoma of the uterine cervix: A case report.

Primary osteosarcoma of the uterine cervix is extremely rare. Only 20 cases have been reported, 19 of which originated in the uterine corpus. We report a case of primary uterine cervical osteosarcoma with pulmonary metastasis in a 30-year-old nulligravida woman. The initial diagnosis was carcinosarcoma of the uterine cervix, as detected by cervical cytology and biopsy analysis. We performed a total hysterectomy, bilateral salpingo-oophorectomy and colostomy without macroscopic residual tumors in the abdominal cavity, but pelvic recurrent tumors appeared 14 days postoperatively. Both recurrent and metastatic tumors were effectively reduced by combination therapy of adriamycin with ifosfamide; however, the patient died as a result of of disease progression nine months after her first visit to our department.

Optimal cytoreductive surgery in patients with advanced uterine carcinosarcoma: A multi-institutional retrospective study from the Japanese gynecologic oncology group.

BACKGROUND: The benefits of cytoreductive surgery for uterine carcinosarcoma (UCS) are unknown. The objective of this study was to determine the impact of optimal surgery on advanced UCS patient survival. METHODS: We performed a multi-institutional, retrospective study of women diagnosed with stage IIIIV UCS between 2007 and 2012. Data were obtained retrospectively from medical records, including demographic, clinicopathologic, treatment, and outcome information. Optimal cytoreductive surgery was defined as surgery resulting in a maximum residual tumor of ≤1cm. The Kaplan-Meier method was used to calculate progression-free survival (PFS) and overall survival (OS), and the Cox regression model was used to examine the impact of selected factors on survival. RESULTS: A total of 225 UCS patients (median age, 63years) were identified, including 136 (60%) with stage III and 89 (40%) with stage IV disease. Among these patients, 170 (76%) received optimal cytoreductive surgery. The median follow-up time was 19months. The median PFS was 11.5months (95% confidence interval [CI], 10.6-13.4) and 8.1months (95% CI, 5.1-9.5) for patients who received optimal and suboptimal cytoreductive surgery, respectively (P<0.0001). The median OS was 37.9months (95% CI, 28.3-not reached) and 18months (95% CI, 9.6-21) for patients who received optimal and suboptimal cytoreductive surgery, respectively (P<0.0001). Residual tumor >1cm was associated with worse OS while pelvic lymph node dissection was associated with improved OS. CONCLUSION: Optimal cytoreductive surgery and pelvic lymph node dissection are associated with improved OS in advanced UCS patients.