Identification and Validation of a Novel Anoikis-Related Gene Signature for Predicting Survival in Patients With Serous Ovarian Cancer.

Background: Ovarian cancer is an extremely deadly gynecological malignancy, with a 5-year survival rate below 30%. Among the different histological subtypes, serous ovarian cancer (SOC) is the most common. Anoikis significantly contributes to the progression of ovarian cancer. Therefore, identifying an anoikis-related signature that can serve as potential prognostic predictors for SOC is of great significance. Methods: We intersected 308 anoikis-related genes (ARGs) and identified those significantly associated with SOC prognosis using univariate Cox regression. A LASSO Cox regression model was constructed and evaluated using Kaplan-Meier and receiver operating characteristic (ROC) analyses in TCGA (The Cancer Genome Atlas) and GSE26193 cohorts. We conducted quantitative real-time polymerase chain reaction (qPCR) to assess mRNA levels and applied bioinformatics to investigate the correlation between risk groups and gene expression, mutations, pathways, tumor immune microenvironment (TIME), and drug sensitivity in SOC. Results: Among 308 ARGs, 28 were significantly associated with SOC prognosis. A 13-gene prognostic model was established through LASSO Cox regression in TCGA cohort. High-risk group had poorer prognosis than low-risk group (median overall survival (mOS): 34.2 vs. 57.1 months, hazard ratio (HR): 2.590, 95% confidence interval (CI): 0.159 - 6.00, P < 0.001). The area under the curve (AUC) values of 0.63, 0.65, and 0.74 reflected the predictive performance for 3-, 5-, and 8-year overall survival (OS) in GSE26193 validation cohort. Functional enrichment, pathway analysis, and TIME analysis identified distinct characteristics between risk groups. Drug sensitivity analysis revealed potential drug advantages for each group. Furthermore, qPCR validation once again confirmed the effectiveness of the risk model in SOC patients. Conclusions: We developed and validated a robust ARG model, which could be used to predict OS in SOC patients. By systematically analyzing the correlation between the risk score of the ARGs signature model and various patterns, including the TIME and drug sensitivity, our findings suggest that this prognostic model contributes to the advancement of personalized and precise therapeutic strategies. Nevertheless, further validation studies and investigations into the underlying mechanisms are warranted.

Integrated analysis of bulk and single-cell RNA sequencing reveals the interaction of PKP1 and tumor-infiltrating B cells and their therapeutic potential for nasopharyngeal carcinoma.

Immunotherapy is an individualized therapeutic strategy for nasopharyngeal carcinoma (NPC). However, few molecular targets are clinically satisfactory. This work aimed to integrate bulk and single-cell RNA sequencing data to identify novel biomarkers involved in NPC. We performed differentially expressed gene (DEG) analysis, Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and immune cell infiltration analysis prior to correlation analysis of the identified genes and immune cells and further assessed the prognostic effects of the biomarkers and immune cells in NPC. As a result, PKP1, a potential molecular biomarker associated with immune infiltration, and tumor-infiltrating lymphocyte-B cells (TIL-Bs) were identified as promising therapeutic targets for NPC. Importantly, immunohistochemistry (IHC) validated that PKP1 protein expression was mainly found in NPC cells rather than noncancerous cells. In addition, the tumor microenvironment (TME) of NPC was characterized by the infiltration of more dendritic cells (DCs) and γδT cells but fewer B cells. Our results suggest that the interaction of PKP1 and TIL-B cells is involved in NPC development. It is possible that TIL-B cells produce immunoglobulin G (IgG) to tumor antigens, such as PKP1, or viral antigens, including EBV and HPV, to execute antitumor ability through DC and T cells. In response, NPC cells express proteins such as PKP1 (absent in normal nasopharynx) to induce myeloid-derived suppressor cell (MDSC) expansion, which subsequently impairs the proliferation of B cells and results in B-cell death by generating iNOS and NOX2. In summary, our findings provide a potential therapeutic strategy for NPC by disrupting the interaction of PKP1 and TIL-Bs in the TME.

The influence of UGT2B7 genotype on valproic acid pharmacokinetics in Chinese epilepsy patients.

PURPOSE: The aim of this study was to investigate the distribution and frequency of genetic polymorphisms in uridine diphosphate glucuronosyltransferase-2B7 (UGT2B7) in epilepsy patients and to evaluate the effect of these on the metabolism of valproic acid (VPA). METHODS: Single nucleotide polymorphisms in UGT2B7 were investigated in 102 epilepsy patients using DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism analysis. The steady-state plasma concentrations of VPA were determined in these patients, who had received VPA (approx. 500-1000 mg/day) for at least 2 weeks. RESULTS: Fourteen patients had the CC genotype at UGT2B7 C802T, 46 carried CT, and 42 carried the TT genotype. At UGT2B7 G211T, 78 patients had the GG genotype, 23 carried GT, and one individual had the TT genotype. The standardized trough plasma concentration of VPA was much lower in those patients with a T allele at UGT2B7 C802T than in those with the CC genotype (TT, 2.11 ± 1.26; CT, 2.31 ± 1.25; CC, 3.02 ± 1.32 µg kg mL(-1) mg(-1), p < 0.01). However, UGT2B7 G211T polymorphisms had no influence on the plasma concentration of VPA (GG, 2.28 ± 1.32, GT, 2.303 ± 1.38 µg kg mL(-1) mg(-1)). CONCLUSION: These results suggested that UGT2B7 C802T may be an important determinant of individual variability in the pharmacokinetics of VPA and that it may be necessary to increase the VPA dose for individuals with a T allele in order to achieve the therapeutic range of 50-100 µg/mL.

Cathepsins mediate tumor metastasis.

Cathepsins are highly expressed in various human cancers, associated with tumor metastasis. It is superfamily, concluding A, B, C, D, E, F, G, H, L, K, O, S, V, and W family members. As a group of lysosomal proteinases or endopeptidases, each member has a different function, playing different roles in distinct tumorigenic processes such as proliferation, angiogenesis, metastasis, and invasion. Cathepsins belong to a diverse number of enzyme subtypes, including cysteine proteases, serine proteases and aspartic proteases. The contribution of cathepsins to invasion in human cancers is well documented, although the precise mechanisms by which cathepsins exert their effects are still not clear. In the present review, the role of cathepsin family members in cancer is discussed.

[Effect of Dahuangzhechong pill on the gene expression spectra of preventing arterial thrombosis].

OBJECTIVE: To investigate the effect of Dahuangzhechong pill on the gene expression spectra of preventing arterial thrombosis, and reveal its mechanism on molecule level. METHODS: Mononuclear cell and blood platelet of the arterial thrombosis patients were separated before and after treatment by Dahuangzhechong pill. Their RNA was extracted respectively and the genes expressions were detected using gene array containing 14,000 gene. RESULTS: 44 genes up-expressed and 299 genes down-expressed in blood platelet, 252 genes expression increased and 299 genes expression decreased in mononuclear cell genes after treated with Dahuangzhechong pill. The cluster analysis showed that the genes contained ion channel and transport protein, apoptosis related protein, DNA synthesis, repair and transcription factor, cell receptor, cell signal and transducin, and protein translation and synthesis, etc. CONCLUSION: Dahuangzhechong pill may prevent arterial thrombosis through genes containing ion channel and transport protein, apoptosis related protein, DNA synthesis, repair and transcription factor, cell receptor, cell signal and transducin, and protein translation and synthesis, etc.

Enhancive effect of N,N'-dinitrosopiperazine on inducing precancerous lesion on nasal and/or nasopharyngeal epithelia of TgN(p53mt-LMP1)/HT mice.

OBJECTIVE: To investigate the enhancive effect of N,N'-dinitrosopiperazine (DNP) on induced carcinogenesis in nasal and/or nasopharyngeal epithelia among TgN(p53mt-LMP1)/HT transgenic mice to examine the underlying mechanism for the development of nasopharyngeal carcinoma (NPC). METHODS: TgN(p53mt-LMP1)/HT transgenic mice and the same strain of C(57)BL/6J wild-type mice both at the age of 5 months were randomly divided into 2 groups in parallel, respectively, i.e., TgN(p53mt-LMP1)/HT cancerous lesion-inducing group (TI), TgN(p53mt-LMP1)/HT control group (TC), C57BL/6J cancerous lesion-inducing group (CI), and C57BL/6J control group (CC). TI and CI mice were treated only with DNP for 16 weeks, twice each week, while TC and CC mice were given the same volume of saline as controls. At the end of treatment, animals were sacrificed to collect epithelial tissue samples from nasal cavity and nasopharynx for pathohistological evaluation by haematoxylin and eosin (HE) staining and for determination on the expression of TRAF2, c-Jun, and p16 by immunohistochemistry. RESULTS: Atypical hyperplasia was more significant in the samples of TI than in those of TC, CI, and CC, with the rates of lesions being 90%, 10%, 0, and 0 (P<0.01) respectively, though DNP was used alone in a much shortened inducing period at less dosage and without the use of carcinogenic promoter 12-O-tetradecanoylphorbol-13-acetate as usual. The expressions of tumor necrosis factor (TNF) receptor-associated factor 2 (TRAF2) and c-Jun in these samples were significantly up-regulated in TI (P<0.01), while the expression of p16 was significantly lower in TI than in the other groups (P<0.01). CONCLUSION: TgN(p53mt-LMP1)/HT mice hold inherited constitutional defect in immune surveillance function, which can be aggravated by environmental carcinogens, such as DNP used even though in a much less strength. The enhanced carcinogenesis-inducing effect of DNP on TgN(p53mt-LMP1)/HT mice should be closely associated with abnormal signaling of activator protein-1 (AP-1) pathway, especially up-regulated expressions of TRAF2 and c-Jun, and down-regulated expression of p16.

HSP70 and mucin 5B: novel protein targets of N,N'-dinitrosopiperazine-induced nasopharyngeal tumorigenesis.

N,N'-Dinitrosopiperazine (DNP) induces nasopharyngeal carcinoma (NPC) and shows organ specificity to the nasopharyngeal epithelium. To investigate its mechanism, the rat NPC model was induced using DNP. Rat NPC and normal nasopharyngeal cells were obtained from the NPC model using laser capture. The total proteins from these cell samples were separated with two-dimension polyacrylamide gel electrophoresis techniques, and highly expressed proteins (> five-fold) were analyzed using matrix-assisted laser desorption/ionization time of flight and bioinformatics. The results showed that HSP70 and mucin 5B expression increased not only in rat NPC but also in atypical hyperplasia nasopharyngeal tissues, a precancer stage of NPC. High-expression of heat shock protein 70 (HSP70) and mucin 5B was further supported by western blot analysis. The immunofluorescence and western-blotting studies further showed that DNP induced the expression of HSP70 and mucin 5B in a dosage-dependent manner in normal nasopharyngeal epithelia cells. Our data indicate that DNP triggers over-expression of HSP70 and mucin 5B, and is involved in nasopharyngeal tumorigenesis. HSP70 and mucin 5B may be important targets in nasopharyngeal tumorigenesis induced by DNP.

[Establishment and evaluation of a rabbit model of arterial thrombosis by collagen encapsulated thread-drawing].

OBJECTIVE: To establish and evaluate a rabbit model of arterial thrombosis by modified thread-drawing. METHODS: Fifty-three rabbits were randomly divided into 6 groups: a normal group, a ligating group,a collagen encapsulated thread-drawing group,a aspirin group,a clopidogrel group, and an aspirin clopidogral group. The endovascular pathological changes in the rabbits were observed, and D-fructose-1,6-diphosphate trisodium salt octahydrate (FDP), D-Dimer and tissue factor (TF) were detected with enzyme linked immunosorbent assay. RESULTS: In the thread-drawing group, thrombus was obvious, and the endovascular elastic membrane was injured seriously compared with the ligating group. After being treated with aspirin and clopidogrel, most arterial thrombus was softened, dissolved and absorbed. Compared with that in the modified thread-drawing group,wet and dry weight of thrombus increased,and the level of D-Dimer, FDP and TF also increased in the modified thread-drawing group (P<0.01). After being treated by aspirin and/or clopidogrel, the wet and dry weight of thrombus and the level of D-Dimer, FDP and TF decreased compared with the control (P<0.01). Aspirin plus clopidogral could obviously reduce the wet and dry weight of thrombus, and reduce the level of D-Dimer and FDP (P<0.01). Aspirin plus clopidogral could obviously inhibit the formation of TF compared with aspirin (P<0.05). CONCLUSION: Arterial thrombosis model by collagen encapsulated thread-drawing which is visible, repeatable and effective is better than thread-drawing. It is suitable for screening anti-thrombosis drugs and evaluating their effect.

[Novel frame-shift mutation of 540 A deletion in GP IIb gene from a patient with Glanzmann thrombasthenia].

OBJECTIVE: To explore the molecular mechanism of Glanzmann thrombasthenia (GT). METHODS: All 45 exons of alphaIIb and beta3 subunit genes as well as their splicing sites were amplified by polymerase chain reaction(PCR) with 40 primer pairs, and then the PCR products were used to screen the gene mutation by single strand conformation polymorphism-polyacrylamide gel electrophoresis (SSCP-PAGE). The mutation was further confirmed by direct DNA sequencing. RESULTS: A DNA band alterated migration was detected after SSCP-PAGE. DNA sequencing showed that a base deletion within the band at the site of 540 in GPIIb gene(540A) was found. CONCLUSION: The frame-shift mutation caused by the deletion of 540A in GPIIb gene is a novel mutation which is a genetic defect in patients with GT.

The hepatitis B virus X protein promotes hepatocellular carcinoma metastasis by upregulation of matrix metalloproteinases.

The hepatitis B virus (HBV) is a major cause of human hepatocellular carcinoma (HCC) which has a very high mortality rate due to high incidence of metastasis. It is unknown whether HBV contributes to HCC metastasis. In this report, we present clinical data obtained from HCC patients indicating that the expression of hepatitis B virus X protein (HBx) in HCC is associated with an increased expression of membrane-type 1 matrix metalloproteinase (MT1-MMP), and matrix metalloproteinase-2(MMP-2), which correlates with a poor prognosis. We further demonstrate experimentally that HBx upregulates MT1-MMP, which in turn induces MMP-2. Significantly, HBx-mediated MMP activation is associated with a marked increase of cell migration, as revealed by both wound-healing and transwell migration assays, suggesting that HBx may facilitate tumor cell invasion by upregulation of MMPs and subsequent destruction of the extracellular matrix. Together, our results support a model in which HBx contributes to HCC metastasis by upregulation of MMPs.

Two-dimensional polyacrylamide gel electrophoresis analysis of indomethacin-treated human colon cancer cells.

AIM: To establish the two-dimensional gel electrophoresis (2-DE) profiles of indomethacin (IN)-treated human colon cancer cell line HCT116, and to provide a new way to study its anti-tumor molecular mechanism through analyzing a variety of protein maps. METHODS: Two-DE profiles of HCT116 were established in IN-treated and untreated groups. Total proteins were separated by immobilized pH gradient-based 2-DE. The gels were stained by silver, scanned by ImageScanner, and analyzed with Image Master software. RESULTS: Clear background, well-resolved and reproducible 2-DE patterns of HCT116 cells were acquired in IN-treated and untreated group. The average deviation of spot position was 0.896+/-0.177 mm in IEF direction and 1.106+/-0.289 mm in SDS-PAGE direction respectively. In IN-treated group, 1169+/-36 spots were detected and 1061+/-32 spots were matched, the average matching rate was 90.6% in three gels. In untreated group, 1256+/-50 spots were detected and 1168+/-46 spots were matched, the average matching rate was 93.0% in three gels. Forty-five differential protein spots were displayed between IN-treated and untreated groups. Of which, 34 protein spots decreased and 9 showed higher expression in IN-treated group, and only two protein spots showed an expression in untreated cells. CONCLUSION: Two-DE profiles of IN-treated and untreated HCT116 cells were established. Apparent 45 different protein spots were detected in IN-treated and untreated HCT116 cells. The analysis on differential protein spots may serve as a new way to study the molecule mechanism of IN-treated colon cancer.

[The gene expression patterns of genetic P77PMC epilepsy-prone rats' hippocampus].

OBJECTIVE: To find out the differentially expressed genes in the hippocampus of the rats with genetic epilepsy so as to lay a foundation for exploring the pathogenesis of epilepsy by means of cDNA array technology. METHODS: Gene expression patterns in the hippocampus of the genetic epilepsy-prone P77PMC rats and normal Wistar rats were established using the alpha-32P-labeled cDNA probes hybridized with the Atlas Rat cDNA Expression Array, and then were analyzed by an image analysis instrument to get the differentially expressed genes. RESULTS: Fifteen genes were found having differential expression patterns in hippocampus between the P77PMC rats and the Wistar rats, while there may be many other differentially expressed genes left undiscovered due to having no appropriate image analysis software. And among the fifteen genes, the expression levels of twelve genes in the P77PMC rats were higher than those in the Wistar rats, while the expression levels of the other three genes were lower. The results of reverse transcription-polymerase chain reaction(RT-PCR) have demonstrated the reliability of cDNA arrays method. CONCLUSION: cDNA array is a powerful tool for identifying differential expression genes of epilepsy on large scales. There are several differentially expressed genes in hippocampus of the P77PMC rats and the Wistar rats. All these identified genes could play potentially important roles in the pathogenesis of epilepsy.

[Study of gene expression difference in lung carcinogenesis by cDNA microarray].

BACKGROUND & OBJECTIVE: Lung cancer is a kind of disease with high incidence and mortality, however its molecular mechanism is not clear yet. This study was designed to investigate gene expression differences among lung cancer tissues, lung paracancerous tissues,matched peripheral normal lung tissues and the metastases of lymph nodes, and to seek the relatively high expressed genes in lung carcinoma tissues, providing possible theoretical basis for early diagnosis and treatment of pulmonary carcinoma. METHODS: Fresh lung cancer tissue, lung paracancerous tissue, matched normal lung tissue and metastases of lymph nodes were deep-frozen in liquid nitrogen; their total RNA were extracted for reversed transcription cDNA probes, which were labeled and subsequently used to hybridize with cDNA microarray with 588 genes. Different gene expression profiles were obtained by analyzing the integrated density (ID) of spot images on the X-ray. RESULTS: In lung cancer tissues, 40 genes were detected to be differentially expressed, 36 of which such as early growth response protein 1 (EGR1), secreted apoptosis related protein 1 (SARP1) were upregulated while the others such as myeloid cell leukemia protein 1 (MCL1) were downregulated. The upregulated genes were mainly oncogene/suppressor gene, cell cycle regulatory gene, growth factors and apoptosis-related genes. In lung paracancerous tissues, 33 genes had different expression, 20 of which such as matrix metalloproteinase-9 (MMP-9) were upregulated, and the other 13 such as MCL1,endothelin 2 (ET2) were downregulated. In metastases of lymph nodes, there were 21 genes found to be differently expressed, 15 of which such as CD40 receptor-associated factor 1 (CRAF1) were downregulated while the rest were upregulated, and the upregulated genes (6 in 15) were mainly the genes associated with adhesion molecules, matrix metalloproteinases and collagen. CONCLUSION: EGR1, SARP1, NDKA, etc. may be the key genes in pulmonary carcinogenesis course. At the same time, MMP9, thrombospondin 2 (TSP2), etc.may play an important role in pulmonary cancer metastasis and infiltration.

[Effect of yiqijiedu granule on the implanted-tumor protein expression in nasopharyngeal carcinoma].

OBJECTIVE: To investigate the inhibitory mechanism of Yiqijiedu granule on the implanted-tumor growth of nasopharyngeal carcinoma in nude mice. METHODS: Twenty nude mice were injected nasopharyngeal carcinoma cells (HNE1), with 5 x 10(6) cells for a nude mouse. Implanted-tumors grew for 20 d, whose volume reached 1 cm x 1 cm x 1 cm. These nude mice were divided into 2 groups: Yiqijiedu group and control group. The Yiqijiedu group was given Yiqijiedu granule, and the control was given normal saline for 30 d, and then were killed. The volume and weight of implanted-tumors were measured. A 100-mg tissue from implanted-tumors was used to extract total protein by current methods, in which the proteins were separated by two-dimension electrophoresis and stained by silver, and protein profiles of implanted-tumors were obtained. Different proteins in the profiles were analyzed by ImageMaster 2D Elite 4.01. Nineteen different proteins, in which 4 expressed in the Yiqijiedu group, 4 expressed in the control, and the other 11 were differently expressed at 5 folds, were identified by MALDI-TOF-MS. RESULTS: The Yiqijiedu granule could inhibit the growth of implanted-tumors. The volume and weight of implanted-tumors in the Yiqijiedu group were (0.207 +/- 0.023) cm3 and (0.132 +/- 0.021) g respectively, and that of the control was (1.342 +/- 0.298) cm3 and (1.017 +/- 0.015) g ( P < 0.05). The inhibitory rate was 84.58%. The analyses of two-dimension electrophoresis and ImageMaster 2D Elite 4.01 showed that there were 567 +/- 49 protein dots in the Yiqijiedu group and 679 +/- 59 in the control. We found 243 proteins were dys-regulated, of which 112 proteins were observed, up-regulated and the other 131 proteins were down-regulated. MALDI-TOF-MS and Database analysis showed that the high expression proteins were HKR2 protein, 10 Phosphoribosyl pyrophosphate synthetase, TNFR superfamily member, and Apoptosis regulator. The lower expression proteins were Fibulin-3, Zinc finger protein 266, Carboxy terminus of HSP70-interacting protein, et al. CONCLUSION: Yiqijiedu granule could inhibit the growth of nasopharyngeal carcinoma, which may be associated with those proteins regulated by itself.

[Effect of Coptis Chinensis compound on the gene expression in transplanted tumor tissue in nasopharyngeal carcinoma cell line of CNE1 by cDNA microarray].

OBJECTIVE: To investigate the effect of Coptis Chinensis compound on the gene expression of transplanted tumor in nasopharyngeal carcinoma cell line of CNE1. METHODS: The cells were injected into Balb/C nude mice, and after the transplanted tumor was established, the nude mice with tumors were treated with Coptis chinensis compound. The nude mice were then killed, tumor tissues were isolated and the total RNA was extracted. Hybridization with a cDNA microarray was conducted using a probe of fluorescent-labeled cDNA mixture that was reversely transcribed from the RNA. The gene expression level was analyzed after scanning the fluorescent intensity by a laser scanner, and further confirmed by RT-PCR. RESULTS: After using Coptis Chinensis compound for 30 days, the size of transplanted tumors were remarkably reduced, and the inhibition rate of tumor growth was 29.5%. In the meantime, the expression of 147 genes in the tissue of implanted tumor treated with the compound altered: the expression of 102 genes was down-regulated, and that of 45 genes was up-regulated. Furthermore, the differential expression of 3 genes was verified by RT-PCR, MAD3 and H731 genes were up-regulated, and that of CHK1 was down-regulated. CONCLUSION: Coptis Chinensis compound can affect the gene expression in the tissue of implanted tumor, which implies that the inhibition of Coptis Chinensis compound on the growth of the implanted tumor with CNE1 cells in nude mice might be associated with the control of gene expression.

[Effect of JIP on the proliferation and apoptosis of nasopharyngeal carcinoma cells].

BACKGROUND & OBJECTIVE: Previous studies showed that JNK signaling pathway activated by LMP1 plays an important role in carcinogenesis of nasopharyngeal carcinoma (NPC). JNK interacting protein (JIP) can inhibit JNK signaling pathway in NPC cell. This study was designed to elucidate the effect of JIP on the proliferation and apoptosis of NPC cells. METHODS: After treatment with JIP at different concentrations and time points, the number of proliferating cells were determined by MTT assay; the ability of proliferation of NPC cells was measured by the rate of cloning formation; cell cycle and the apoptotic rate of NPC cells was assayed by flow cytometry. RESULTS: 1. MTT assay showed that cell proliferation was significantly inhibited by JIP in a dose- and time-dependent manner. After treatment with JIP for 24, 48, and 72 hours, the rate of survival cells were 77.8%, 59.2%, and 61.8%, respectively. 2. The number and volume of colonies were decreased after transfection with JIP. 3. The number of cells in S phase was decreased from 25.87% to 19.96%, and the number of cells in G0/G1 phase was elevated from 66.24% to 71.89% after treatment with JIP. 4. In contrast to the control group, the 24 hours apoptotic rate was elevated from 1.25% to 8.25% (about 6.6 times); the 48 hours apoptotic rate was elevated from 1.04% to 31.45% (about 30 times). CONCLUSIONS: The results demonstrated that JIP inhibit the growth of nasopharyngeal carcinoma through arresting the cell cycle at G1/S checkpoint and triggering the apoptosis of cells. Data suggest that JIP is a potent molecular drug for the treatment of the patients with nasopharyngeal carcinoma.