First American Cancer Patient to Receive Dicycloplatin (DCP) Chemotherapy Achieves Remission After Seven Weeks of DCP Capsules - A Case Report.

BACKGROUND: The majority of bladder cancer patients experience recurrence. Cisplatin is the standard chemotherapy for muscle-invasive bladder cancer though adverse effects are often severe. CASE REPORT: Intravenous (IV) dicycloplatin (DCP) sustained remission in an American bladder cancer patient for five years. A recurrent mass was observed in July 2021. The patient received DCP capsules for seven weeks with no significant side-effects. Complete blood count with differential and a basic metabolic panel showed no adverse effects of DCP capsules on the bone marrow, liver or renal parameters. Cystoscopy after oral DCP found no evident bladder tumors; cytology was negative for high-grade urothelial carcinoma. CONCLUSION: In this patient, DCP-capsules appeared to be as effective as DCP-IV for achieving bladder cancer remission. Both forms of DCP chemotherapy are convenient, active against several cancer types, with decreased adverse effects compared to cisplatin. Both have been available for treating cancer patients in China. A USA clinical trial of DCP in bladder and other cancers appears warranted.

Detecting the prevalence of bacterial colonization on tunneled cuffed hemodialysis catheters using quantitative PCR targeting 16S rRNA and scanning electron microscopy.

BACKGROUND AND OBJECTIVES: Tunneled cuffed hemodialysis catheters (TCC) get colonized by microorganisms, increasing risk for catheter related bacteremia (CRB). Our objective was to detect the prevalence of bacterial colonization of TCC by using quantitative PCR (qPCR) targeting 16S rRNA and by determining the intraluminal adherent biological material (ABM) coverage. METHODS: A total of 45 TCC were investigated. The 16S rRNA qPCR technique was used to detect bacterial colonization after scraping the intraluminal ABM. Proximal, middle, and distal TCC were evaluated by scanning electron microscopy (SEM) to determine the percentage (%) of intraluminal ABM coverage. All catheters were cultured following sonication. RESULTS: A total of 45 TCC were removed: 7 due to CRB, 3 for suspected CRB and 35 were removed for non-infectious etiologies. Bacterial colonization was detected in 27 TCC by documenting 16S rRNA qPCR (+) results (60%). Seven of these 16S rRNA qPCR (+) catheters were removed due to CRB. There was no difference in demographic, clinical, or laboratory values between the 16S rRNA (+) versus (-) TCC. The 16S rRNA qPCR (-) outcome was highly associated with CRB-free status with negative predictive value of 100%. Bacterial colonization was documented in 10 TCC using catheter cultures (22%), which was significantly less compared to qPCR method (p = 0.0002). ABM were detected in all catheter pieces, with mean intraluminal surface coverage (ABMC) of 68.4 ± 26.1%. ABM was unlikely to be microbial biofilm in at least 36% of removed TCC as their 16S rRNA qPCR and catheter culture results were both negative. CONCLUSIONS: Detecting bacterial colonization of TCC was significantly higher with 16S rRNA qPCR compared to catheter cultures. The 16S rRNA qPCR (-) cannot be predicted and was strongly associated with absence of CRB. Intraluminal ABM was not associated with microbial presence in about 1/3 of the TCC. These pieces of evidence may help to improve prophylactic strategies against CRB.

Particular internal recirculation frequency scope for enhancing denitrifying phosphorus removal in an oxidation ditch.

This study investigated the influence of the unique internal recirculation characteristics of an oxidation ditch (OD) system, namely, the internal recirculation frequency (IRF) on denitrifying phosphorus removal (DNPR). The ratios of denitrifying polyphosphate-accumulating organisms (DPAOs) to polyphosphate-accumulating organisms (PAOs) under different IRF conditions were measured using a batch experiment. On this basis, the variation of nutrient transformations was studied using the IRF changes by the mass balance method. The results showed that, for the OD system that had an anaerobic zone upstream from the circular corridor and set anoxic and aerobic zones along the circular corridor, when the IRF was between 3.4 h-1 and 7.5 h-1, the DPAOs/PAOs ratio reached about 50%. Approximately 20% of the total phosphorus (TP) was removed and over 11% of the total nitrogen (TN) was transformed into nitrogen gas by the DNPR process, and meanwhile the total removal efficiencies of the TP and TN were over 93% and 80%. When the IRF was greater than 11.5 h-1, the TN removal efficiency decreased significantly, and this was not conducive to simultaneous nitrogen and phosphorus removal. The results indicated that the OD process would possess a better DNPR potential if the IRF were controlled within the proper scope.

Adverse Effects Profile of Dicycloplatin (DCP) Offers Chemotherapeutic Advantage Over Cisplatin and Carboplatin.

BACKGROUND/AIM: Platinum-based chemotherapy often fails due to its severe adverse effects. The aim of this study was to examine the adverse effects profile and efficacy of dicycloplatin and compare them to those of cisplatin and carboplatin. MATERIALS AND METHODS: Cystoscopy surveillance of the first American cancer patient treated with dicycloplatin was performed quarterly. In vitro and in vivo studies were conducted using immunoblotting and flow cytometry to assess immune status of spleen and bone marrow of mice treated with dicycloplatin, cisplatin and carboplatin. RESULTS: The American patient did not suffer clinically significant myelosuppression; dicycloplatin has sustained remission in this patient to date. Experimental studies showed that dicycloplatin is less toxic to bone marrow and spleen of mice than cisplatin and carboplatin. CONCLUSION: Dicycloplatin is a promising drug in cancer chemotherapy with less aggressive side-effects than those typically associated with cisplatin and carboplatin. This is an important therapeutic advantage in cancer chemotherapy. Clinical investigation of dicycloplatin as an alternative to cisplatin or carboplatin is warranted.

[Effects of Long-term Poly-P Deficiency on the Metabolic Properties of Accumulibacter in AO-SBR System].

To investigate the changes in microbial community structure and metabolic properties of Accumulibacter under long-term Poly-P deficiency, an activated sludge enriched with Accumulibacter was inoculated into two SBR reactors, where sodium acetate and sodium propionate were used separately as organic carbon sources. The two reactors were operated for 60 days with an influent PO43--P concentration of 2.5 mg·L-1. The phosphorus removal performance, sludge production, and changes in the microbial community structure of the systems were analyzed. The results indicated that both SBR systems showed good performance of phosphorus and organic matter removal. However, microorganisms in both systems showed glycogen-accumulating metabolism properties under long-term Poly-P deficiency. In the unfavorable environment of long-term Poly-P deficiency, Accumulibacter Ⅰ maintained a high abundance (40%±7%) in the propionate SBR system, indicating that Accumulibacter Ⅰ had higher metabolic activity and its metabolic properties could be independent of Poly-P for survival under Poly-P deficiency for a long period. In comparison, propionate is more conducive to Accumulibacter adaptation to lower phosphorus loads, and Accumulibacter Ⅰ is more competitive than Accumulibacter Ⅱ under lower phosphorus loads.

Chronic Supplementation of Curcumin Enhances the Efficacy of Antidepressants in Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled Pilot Study.

Major depressive disorder is a devastating mental illness leading to a lifetime prevalence of higher than 16% on individuals. The treatment delay and inevitable adverse effects are major limitations of current depression interventions. Emerging evidence indicates that curcumin produced significant antidepressant properties in depression in both rodents and humans without adverse effects. Therefore, it is necessary to further clarify the antidepressant actions of curcumin and the underlying mechanism in depressed patients. A total of 108 male adults aged between 31 and 59 years were systematically recruited in Tianjin Anding Hospital. Subjects were administered the Chinese version of 17-item Hamilton Depression Rating Scale and Montgomery-Asberg Depression Rating Scale that measures different scores of depressive symptoms. The subjects were asked to take 2 capsules containing either 1000 mg of curcumin or placebo soybean powder daily for 6 weeks on the basis of their current antidepressant medications. The plasma levels of interleukin 1ß, tumor necrosis factor α, brain-derived neurotrophic factor, and salivary cortisol were measured by enzyme-linked immunosorbent assay before and after curcumin or placebo treatment during the 6-week procedure. Chronic supplementation with curcumin produced significant antidepressant behavioral response in depressed patients by reduction of 17-item Hamilton Depression Rating Scale and Montgomery-Asberg Depression Rating Scale scores. Furthermore, curcumin decreases inflammatory cytokines interleukin 1ß and tumor necrosis factor α level, increases plasma brain-derived neurotrophic factor levels, and decreases salivary cortisol concentrations compared with placebo group. These findings indicate the potential benefits of further implications of supplementary administration of curcumin to reverse the development of depression and enhance the outcome of antidepressants treatment in major depressive disorder.

Downregulation of ATG14 by EGR1-MIR152 sensitizes ovarian cancer cells to cisplatin-induced apoptosis by inhibiting cyto-protective autophagy.

Cisplatin is commonly used in ovarian cancer treatment by inducing apoptosis in cancer cells as a result of lethal DNA damage. However, the intrinsic and acquired resistance to cisplatin in cancer cells remains a big challenge for improving overall survival. The cyto-protective functions of autophagy in cancer cells have been suggested as a potential mechanism for chemoresistance. Here, we reported MIR152 as a new autophagy-regulating miRNA that plays a role in cisplatin-resistance. We showed that MIR152 expression was dramatically downregulated in the cisplatin-resistant cell lines A2780/CP70, SKOV3/DDP compared with their respective parental cells, and in ovarian cancer tissues associated with cisplatin-resistance. Overexpression of MIR152 sensitized cisplatin-resistant ovarian cancer cells by reducing cisplatin-induced autophagy, enhancing cisplatin-induced apoptosis and inhibition of cell proliferation. A mouse subcutaneous xenograft tumor model using A2780/CP70 cells with overexpressing MIR152 was established and displayed decreased tumor growth in response to cisplatin. We also identified that ATG14 is a functional target of MIR152 in regulating autophagy inhibition. Furthermore, we found that EGR1 (early growth response 1) regulated the MIR152 gene at the transcriptional level. Ectopic expression of EGR1 enhanced efficacy of chemotherapy in A2780/CP70 cells. More importantly, these findings were relevant to clinical cases. Both EGR1 and MIR152 expression levels were significantly lower in ovarian cancer tissues with high levels of ERCC1 (excision repair cross-complementation group 1), a marker for cisplatin-resistance. Collectively, these data provide insights into novel mechanisms for acquired cisplatin-resistance. Activation of EGR1 and MIR152 may be a useful therapeutic strategy to overcome cisplatin-resistance by preventing cyto-protective autophagy in ovarian cancer.

Clinical pharmacology of an atrasentan and docetaxel regimen in men with hormone-refractory prostate cancer.

PURPOSE: This study was conducted to evaluate potential pharmacokinetic interactions between docetaxel and atrasentan as part of a phase I/II clinical trial. METHODS: Patients with prostate cancer were treated with intravenous docetaxel (60-75 mg/m(2)) every 3 weeks and oral atrasentan (10 mg) daily starting on day 3 of cycle 1 and then given continuously. The pharmacokinetics of both drugs were evaluated individually (cycle 1, day 1 for docetaxel; day 21 for atrasentan) and in combination (cycle 2, day 1 for both drugs). Pharmacogenomics of alpha-1-acid glycoprotein (AAG) were also explored. RESULTS: Paired pharmacokinetic data sets for both drugs were evaluable in 21 patients. Atrasentan was rapidly absorbed and plasma concentrations varied over a fourfold range at steady state within a typical patient. The median apparent oral clearance of atrasentan was 17.4 L/h in cycle 1 and was not affected by docetaxel administration (p = 0.9). Median systemic clearance of docetaxel was 51.1 L/h on the first cycle and significantly slower (p = 0.01) compared with that obtained during co-administration of atrasentan, 61.6 L/h. Docetaxel systemic clearance in cycle 1 was 70.0 L/h in patients homozygous for a variant allele in AAG compared with 44.5 L/h in those with at least one wild-type allele (p = 0.03). CONCLUSION: Genetic polymorphism in AAG may explain some inter-patient variability in docetaxel pharmacokinetics. The systemic clearance of docetaxel is increased by approximately 21 % when given concomitantly with atrasentan; however, atrasentan pharmacokinetics does not appear to be influenced by docetaxel administration.

Dicycloplatin, a novel platinum analog in chemotherapy: synthesis of chinese pre-clinical and clinical profile and emerging mechanistic studies.

Dicycloplatin (DCP) has better solubility and stability than both cisplatin and carboplatin. Pre-clinical and phase I studies demonstrated significant antitumor activity and fewer adverse events than carboplatin. Phase II clinical trials in advanced non-small cell lung cancer found efficacy and safety of DCP-plus-paclitaxel comparable to carboplatin-plus-paclitaxel but better tolerability. This article summarizes and reviews pre-clinical and clinical data for dicycloplatin from the Chinese medical literature. We also report on new mechanistic findings in our laboratory in West Virginia, USA. Patient blood samples were collected for DCP-prototype determination by liquid chromatography mass spectrometry (LC-MS/MS). Molecular studies of ovarian cancer cells treated with DCP or cisplatin were carried out for gene-signature profiling using immunoblotting. Pharmacokinetic mass-spectrometry showed different spectrum profiles of DCP and carboplatin in plasma. Plasma concentration of DCP prototype was 17.1 µg/ml 2h after administration, with a peak concentration of 26.9 µg/ml at 0.5 h. Immunoblotting showed DCP-induced activation of DNA damage pathways, including double-phosphorylated checkpoint kinase 2 (CHK2) and breast cancer 1 (BRCA1) and triple-phosphorylated p53, compared to controls. Cisplatin produced a similar profile, with increased p53 protein. DCP and cisplatin activate DNA-damage response through similar pathways. DCP may be more soluble and stable, and better-tolerated.

Inhibition of calcineurin in the prefrontal cortex induced depressive-like behavior through mTOR signaling pathway.

RATIONAL: Although it has been recognized that inhibition of calcineurin induced depressive-like behavior, the underlying neural mediators have not yet been identified. Mammalian target of rapamycin (mTOR), a serine/threonine protein kinase that regulates protein synthesis in synapses, has been demonstrated to be involved in the rapid antidepressant effects of ketamine. OBJECTIVE: To investigate a potential role of mTOR signaling pathway which interferes with depressive-like behavior induced by calcineurin blockade and to determine the neurobiological mechanisms underlying mood-related disorders. METHODS: Calcineurin inhibitor cyclosporine A (CsA) and tacrolimus (FK506) were microinjected into the medial prefrontal cortex (mPFC) in rats, and the depressive-like behavior was measured in sucrose preference test and forced swim test. Additionally, mTOR activity was tested by the levels of phosphorylation of p70s6 kinase (p70s6k) and 40S ribosomal protein S6 (rps6). RESULTS: Chronic microinjection of CsA or FK506 into mPFC increased depressive-like behaviors and decreased mTOR activity, but acute CsA or FK506 had no effects on both behavioral phenotype and mTOR activity. Furthermore, activation of mTOR by NMDA reversed the depressive-like behavior induced by chronic CsA or FK506 administration. Moreover, inhibition of mTOR by rapamycin reversed the antidepressant effects of ketamine. Finally, traditional antidepressant venlafaxine prevented the depressive-like performance induced by chronic CsA or FK506 treatment. CONCLUSION: These findings indicate that calcineurin-inhibition-induced depressive-like behavior is mediated by blockade of the mTOR signaling pathway and raise the possibility that stimulation of specific brain mTOR may be sufficient to decrease risk of affective disorders in patients treated with calcineurin inhibitor.

Disease-syndrome combination clinical study of psoriasis: present status, advantages, and prospects.

Psoriasis is an immune-abnormal, chronic, proliferative skin disease determined by polygenic inheritance and induced by a number of environmental factors. It causes worldwide concern because of its high-prevalence, harmful and incurable characteristics. Over the years, Chinese medicine (CM) treatment of psoriasis has accumulated a wealth of clinical experience. Disease-syndrome combination, which achieves more satisfactory clinical effect, is the basis to highlight the special CM advantages in treating psoriasis. In this paper, we review the advantages of treating psoriasis with the combination of disease and syndrome, analyze the prospects of research on treating psoriasis combining disease with syndrome. We also make a point that there are several key points for the clinical research of combination of disease and syndrome. It can be expected that carrying out clinical research on the combination of disease and syndrome will help improve the clinical efficacy of medical treatment of psoriasis, which will be the main direction of research in the future.

Correlations among ERCC1, XPB, UBE2I, EGF, TAL2 and ILF3 revealed by gene signatures of histological subtypes of patients with epithelial ovarian cancer.

The aim of this study was to better understand the mechanisms of tumor development and disease progression in human epithelial ovarian cancer. Fifty genes were screened for gene signature; 20 expressed genes were assessed in tumor and normal samples of EOC patients by RT-PCR. Expression of UBE2I, EGF, TAL2 and ILF3 was validated by qPCR on the ABI Prism 7000 Detection System. ERCC1 and XPB expression was previously determined by RT-PCR in these specimens. Statistical analyses include two-sided Kruskal-Wallis test, pairwise comparison, Pearson correlation coefficient and paired t-test. In comparison to normal samples, 6 genes demonstrated distinct expression patterns in tumor tissues, with high expression observed for ERCC1, XPB and ILF3 (p=0.001, 0.0007 and 0.002, respectively) and low expression observed for TAL2 and EGF (both p<0.0001). This differential expression pattern between normal and tumor tissues may reflect in part the development of ovarian cancer. Significant differences in expression patterns of these genes in clear cell, endometrioid, mucinous and serous ovarian cancer were observed. Comparison of expression of any two EOC subtypes revealed multiple gene involvement in histopathological differentiation and cancer progression. A positive association was found between ERCC1 and XPB expression (r=0.53, p<0.0001) and between TAL2 and EGF expression (r=0.817, p<0.0001) suggesting the existence of gene linkage in these tumors. The differences in expression patterns of studied genes between tumors and normal specimens, between histological subtypes and correlations among studied genes, may indicate their involvement in tumor growth and disease progression in human epithelial ovarian cancer. Further investigation of these genes may enable better understanding of the molecular mechanism of tumorigenesis and identification of potential biomarkers.

The Role of Wild-Type p53 in Cisplatin-Induced Chk2 Phosphorylation and the Inhibition of Platinum Resistance with a Chk2 Inhibitor.

The major obstacle in platinum chemotherapy is the repair of platinum-damaged DNA that results in increased resistance, reduced apoptosis, and finally treatment failure. Our research goal is to determine and block the mechanisms of platinum resistance. Our recent studies demonstrate that several kinases in the DNA-repair pathway are activated after cells are exposed to cisplatin. These include ATM, p53, and Chk2. The increased Chk2 phosphorylation is modulated by p53 in a wild-type p53 model. Overexpression of p53 by cDNA transfection in wt-p53 (but not p53 deficient) cells doubled the amount of Chk2 phosphorylation 48 hours after cisplatin treatment. p53 knockdown by specific siRNA greatly reduced Chk2 phosphorylation. We conclude that wild-type p53, in response to cisplatin stimulation, plays a role in the upstream regulation of Chk2 phosphorylation at Thr-68. Cells without normal p53 function survive via an alternative pathway in response to the exogenous influence of cisplatin. We strongly suggest that it is very important to include the p53 mutational status in any p53 involved studies due to the functional differentiation of wt p53 and p53 mutant. Inhibition of Chk2 pathway with a Chk2 inhibitor (C3742) increased cisplatin efficacy, especially those with defective p53. Our findings suggest that inhibition of platinum resistance can be achieved with a small-molecule inhibitor of Chk2, thus improving the therapeutic indices for platinum chemotherapy.

Determination of textile dyeing wastewater COD components by comparison with respirometry and full-scale data.

A Modified Activated Sludge Model No. 1 (M-ASM1), including six COD components (S1, S(S), X1, X(S), X(H), and S(O)) and three biochemical processes (aerobic growth of heterotrophs, aerobic decay of heterotrophs and hydrolysis of entrapped organics) was used to simulate the anaerobic hydrolysis-aeration-sedimentation treatment series in a full-scale textile dyeing wastewater treatment plant (WWTP) with an influent flow rate of 200,000 m3/d. Using a respirometry method, the influent COD components of the WWTP activated sludge system were estimated. Then, calibration equations were set up depending on the full-scale treatment plant running data in order to calibrate the measurement results. This paper indicates that the influent COD components of a low biodegradability wastewater can be estimated using a respirometry method coupled with a calibration procedure based on full-scale plant running data.

A Polymorphic Variant of AFAP-110 Enhances cSrc Activity.

Enhanced expression and activity of cSrc are associated with ovarian cancer progression. Generally, cSrc does not contain activating mutations; rather, its activity is increased in response to signals that affect a conformational change that releases its autoinhibition. In this report, we analyzed ovarian cancer tissues for the expression of a cSrc-activating protein, AFAP-110. AFAP-110 activates cSrc through a direct interaction that releases it from its autoinhibited conformation. Immunohistochemical analysis revealed a concomitant increase of AFAP-110 and cSrc in ovarian cancer tissues. An analysis of the AFAP-110 coding sequence revealed the presence of a nonsynonymous, single-nucleotide polymorphism that resulted in a change of Ser403 to Cys403. In cells that express enhanced levels of cSrc, AFAP-110(403C) directed the activation of cSrc and the formation of podosomes independently of input signals, in contrast to wild-type AFAP-110. We therefore propose that, under conditions of cSrc overexpression, the polymorphic variant of AFAP-110 promotes cSrc activation. Further, these data indicate amechanismby which an inherited genetic variation could influence ovarian cancer progression and could be used to predict the response to targeted therapy.

HPV infection and EGFR activation/alteration in HIV-infected East African patients with conjunctival carcinoma.

BACKGROUND: There has been substantial growth in the numbers of patients with conjunctival squamous cell carcinoma infected with HIV in East Africa. The natural history of the conjunctival squamous cell carcinoma appears to be unique in this region of the world, but the etiologic mechanism unclear and therapeutic options limited. This research was carried out to determine if conjunctival squamous cell carcinoma harbors human papillomavirus DNA and is associated with activation of the EGFR signaling pathway. Positive findings would identify etiologic causes and provide clinical guidance to improve treatment. METHODS/FINDINGS: Expression of p-MAPK/MAPK, p-Akt/Akt and p-EGFR/EGFR in cell nuclei and cytoplasm of 38 FFPE specimens were assessed by immunohistochemistry; HPV genotype was detected by qPCR assay; EGFR mutation was assessed by DNA sequencing analysis; and EGFR mRNA expression was measured using relative qPCR. Statistical analyses included two-sided Fisher exact test or chi-square test, Spearman correlation coefficient and ANOVA. HPV 18 was found in 61% of samples, with HPV 16 double-genotype in 6 patients (16%). Immunohistochemistry and qPCR data suggest that activation and expression of the EGFR signaling pathway is related to disease progression of conjunctival cancer. The associations between cytoplasmic p-MAPK, cytoplasmic p-Akt and tumor invasiveness were significant (p = 0.05 or 0.028). Nuclear p-EGFR appeared only in invasive tumors. A significant positive association between EGFR expression and disease invasiveness was observed (p = 0.01). A SNP in 10 patients and one missense mutation were found within EGFR tyrosine kinase domain. Statistical analysis indicates that patients with measurable EGFR expression more likely harbor EGFR mutations, compared to those with negative EGFR expression (35.3% vs. 0%). CONCLUSIONS/SIGNIFICANCE: We conclude that HPV types 16/18 infection is frequent in East African patients with AIDS-associated squamous cell carcinoma of the conjunctiva. EGFR activation/alteration may contribute to and sustain the high prevalence of this cancer. Our findings hint that adoption of HPV vaccination strategies may impact the incidence of conjunctival carcinoma. Agents that target the EGFR pathway may have potential therapeutic benefit.

Gene expression patterns in the histopathological classification of epithelial ovarian cancer.

The purpose of this study was to screen cancer-related genes and to identify histopathological gene expression patterns as potential biomarkers in human epithelial ovarian cancer (EOC). Fifty genes were screened by reverse-transcription polymerase chain reaction assay with cDNA from 83 EOC tissues and 48 normal ovarian specimens of ovarian cancer patients and evaluated by gel electrophoresis analysis. Twenty expressed genes were assessed by real-time relative-quantity (RQ)-PCR in 30 EOC specimens for gene signature study. Four genes, TAL2, EGF, ILF3 and UBE2I, were investigated for gene expression patterns in histopathological classification of EOC. RQ-value (Ct, ΔCt, ΔΔCt, RQ and gene expression plots) was generated by ABI 7500 Fast System SDS Software (version 1.4). SPSS 15.0 software was used for statistical analysis. Using real-time RQ-PCR, we found that TAL2, EGF, ILF3 and UBE2I demonstrated distinct expression patterns in histological types of epithelial ovarian cancer. The expression of ILF3 and UBE2I in tumors was significantly higher than in normal tissue, with extremely high expression in serous carcinomas compared to mucinous, endometrium and clear cell carcinomas. In addition, ILF3 and UBE2I were overexpressed in advanced stage and advanced grade ovarian cancer, compared to early stage or well-differentiated ovarian cancer. This is the first report of TAL2 and ILF3 expression in the normal human ovary and epithelial ovarian cancer. Our results indicate that overexpression of ILF3 and UBE2I in advanced stage and advanced grade suggest that these two genes may play an important role in tumorigenesis/tumor progression and pathological differentiation of the disease. Notably, ILF3 plays a role in DNA binding activity and transcriptional and post-transcriptional regulation; UBE2I is required in ubiquitination and sumoylation and is involved in DNA repair and apoptosis of cells. Further investigations to reveal the molecular mechanisms related to the activation of ILF3 and UBE2I in the development of EOC are warranted.

Antisense telomerase RNA inhibits the growth of human glioma cells in vitro and in vivo.

Telomerase is implicated in the development of cellular immortality and oncogenesis. It has been shown that telomerase activity is considerably higher in the tissue of many different cancers than in normal tissue, and that the inhibition or downregulation of telomerase activity can prevent the malignant proliferation of tumor cells. Antisense oligonucleotides have been widely used in suppressing the expression of genes and, therefore, in the present research, we evaluated the effect of antisense human telomerase RNA (hTR) on glioma cell growth in vitro and in vivo. We showed that antisense hTR cDNA significantly inhibited TJ905 human glioma cell proliferation in vitro and tumor growth in vivo, as determined by MTT assay and by measuring the volume of glioma in nude mice. Consistent with these results, we found that telomerase activity and the mRNA levels of hTR and hTERT (human telomerase reverse transcriptase) expression were markedly decreased in tumor cells treated with antisense hTR cDNA, as assessed by TRAP (telomeric repeat amplification protocol) assay and RT-PCR (reverse transcription-polymerase chain reaction) analysis. Our study conclusively demonstrates that antisense hTR effectively inhibits the growth of human glioma cells in vitro and in vivo and, thus, may be potentially used for gene therapy of malignant gliomas and other cancers.

Protein phosphatase 2A interacts with Chk2 and regulates phosphorylation at Thr-68 after cisplatin treatment of human ovarian cancer cells.

High-fidelity maintenance of genomic integrity in eukaryotes is ensured by cell cycle checkpoints and DNA repair. The checkpoint kinase, Chk2, has been implicated in both of these responses. In response to DNA damage, Chk2 is initially phosphorylated at Thr-68, which leads to its full activation. The fully activated Chk2 then phosphorylates downstream substrates of cell cycle control. However, the mechanism of inactivation of Chk2 is still unknown. Protein phosphatase type 2A (PP2A) plays an essential role in cell cycle regulation and induction of G2 arrest by a mechanism of phosphorylation/dephosphorylation with a variety of protein kinases. Data from our investigation provide evidence that, in response to cisplatin exposure, PP2A associates with Chk2 as a complex in cells and functions as a negative regulator of Chk2 activation by dephosphorylating p-Chk2. Results from immunostaining and coimmunoprecipitation demonstrate that Chk2 and PP2A can colocalize in cells, and the holoenzyme of PP2A (subunits A, B and C) coimmunoprecipitates with p-Chk2. Further, inhibition of PP2A by okadaic acid, an inhibitor of PP2A, and by small interfering RNA (siRNA) to PP2A results in enhanced Chk2 phosphorylation, implicating a direct enzyme-substrate relationship. An in vitro PP2A dephosphorylation assay shows that PP2A dephosphorylates p-Chk2 in a cell-free system. These findings suggest that the protein serine/threonine kinase, Chk2, is activated after cisplatin exposure and negatively regulated by a tightly associated protein serine/threonine phosphatase, PP2A.