[Show abstract][Hide abstract] ABSTRACT: Many physiological, biochemical and behavioral processes are under circadian regulation, which is generated by an in- ternal time-keeping mechanism referred to as biological clock in almost all organisms from bacteria to mammals. Although the substantial evidences that the circadian clock could modulate the morbidity and efficacy of anticancer therapy have been proposed, underlying mechanisms for chronotherapy has been only poorly elucidated, and it has not been popular in clinic. The aim of this study was to determine the relationship between the expression of P-glycoprotein (P-gp)/MDR1, which is one of the important molecules in anti-cancer drug resistance, and circadian rhythm in KB-C2 cells. The present study demonstrated that both MDR1 expression level and its promoter activity oscillated after treatment with high concentration of fetal bovine serum. Moreover, cytotoxic effect of taxol were dependent on the fluctuated levels of MDR1. These results suggest that the circadian rhythm of MDR1 may have an influential effect on cytotoxicity of anti-cancer drug and could be available for chemotherapy in clinic.
Annals of Cancer Research and Therapy 07/2010; 18(1):13-18. DOI:10.4993/acrt.18.13
[Show abstract][Hide abstract] ABSTRACT: Purpose: The cyclooxygenases (COX) catalyze the formation of prostaglandins, affecting cell proliferation and altering the response of the immune system in malignant cells. The inducible forms of COX-1 and COX-2, have been shown to be im- portant in carcinogenesis. Peroxisome-proliferator activated receptor gamma (PPARgamma) belongs to a family of nuclear receptors and acts as receptor for peroxisome-proliferators, steroids, retinoic acids, and polyunsaturated fatty acids. The aim of this study is to investigate the clinicopathological significance of the expressions of COX-1, COX-2 and PPARgamma genes in 90 colorectal carcinomas.
Experimental Design: The expressions of COX-1, COX-2 and PPARgamma genes were examined in surgical specimens of colorectal carcinoma and corresponding normal tissues from 90 patients using modified Real Time PCR. Result: There was increase in the expression of PPARgamma in colorectal carcinomas compared to paired normal tissue (p = 0.03). Greater COX-2 expression was correlated with lymph node metastasis (p = 0.02) and venous invasion (p = 0.01).
Annals of Cancer Research and Therapy 07/2010; 18(1):6-12. DOI:10.4993/acrt.18.6
[Show abstract][Hide abstract] ABSTRACT: Many behavioral processes are under circadian regulation in almost all organisms from bacteria to mammals. Although substantial evidences support the idea that circadian clock could modulate the efficacy of anticancer therapy, the mechanism(s) has not been clear. Here we demonstrated that expression of topoisomerase I (top1) mRNA and its promoter activity underwent circadian oscillation after serum-rich medium treatment in HCT 116 cells. Moreover, the formation of cleavage complex composed of top1 and top1 poison, camptothecin (CPT), detected by nicking assay was also oscillated. Colony formation assay indicated that cytotoxicity of 8h-CPT treatment was significantly higher at 4-h after serum-shock than at 20-h (p = 0.0289). In addition, dexamethasone treatment also induced circadian rhythm of top1 in HCT 116 cells. These results raise the possibility that the circadian rhythm of top1, which would be induced by some types of drugs such as dexamethasone, could be considered for chemotherapy in clinic.
Annals of Cancer Research and Therapy 07/2010; 18(1):19-27. DOI:10.4993/acrt.18.19
[Show abstract][Hide abstract] ABSTRACT: Xeroderma Pigmentosum Group G (XPG) is one of the proteins involved in nucleotide excision repair, and is related to Xeroderma pigmentosum, a rare hereditary disease characterized by hypersensitivity to ultraviolet light, high incidence of actinic carcinomas and neurological abnormalities. The aim of this study was to investigate the expression of XPG in sporadic human breast carcinoma and to determine whether it's expression was predictive for response to tamoxifenbased chemotherapy and survival in the patients with breast carcinoma. We investigated the expression levels of mRNA and protein of XPG in 43 sporadic human breast carcinomas by real time PCR and immunohistochemical analysis. All the patients were primarily treated with reductive surgery and doxorubicin and tamoxifen-based regimen. XPG expression was observed in 35 of 43 cases (81.4%). The proportion of the cases with high expression level of XPG was 48.8% (21/43 cases). Interestingly, the cases showing the expression of mRNA without detectable levels of protein were observed in 5 of 43 cases (11.6%). The sequence analysis showed one mutation such as deletion at codon117 that leads to a following stop codon. Moreover, patients with high expression levels significantly had a poorer overall survival than those with low expression level (P = 0.048). These results suggest that XPG may be the useful molecular marker to choose the anticancer drugs for tamoxifen-based chemotherapy in human sporadic breast carcinoma.
Annals of Cancer Research and Therapy 07/2010; 18(1):37-42. DOI:10.4993/acrt.18.37
[Show abstract][Hide abstract] ABSTRACT: Angiogenesis is essential for tumor growth and metastasis, therefore, inhibition of angiogenesis has emerged as a new therapy to treat cancers. Although vascular endothelial cell growth factor (VEGF) induces tumor growth and metastasis by its angiogenic property, the mechanism(s) of circadian rhythm in angiogenesis has not been fully analyzed. Here we revealed that VEGF mRNA expression level, protein expression level and its promoter activity belonged to circadian rhythm in human colon carcinoma cell line, HCT116 cells. HIF (hypoxia inducible factor)-1α also underwent circadian oscillation at levels of mRNA and promoter activity. Co-transfection of Bmal1 and Clock enhanced HIF-1α luciferase activity, but not VEGF luciferase activity, indicating that VEGF is not a direct target of Bmal1/Clock. However, inhibition of HIF-1α by chrysin resulted in disappearance of VEGF circadian oscillation, suggesting that HIF-1α is involved in the regulation of the VEGF expression. Moreover, circadian oscillation of VEGF and HIF-1α was induced by 100 nM of dexamethasone. These results suggest the link between the circadian oscillation between VEGF and HIF-1α, raising a possible strategy for chronotherapy in clinic.
Annals of Cancer Research and Therapy 07/2010; 18(1):28-36. DOI:10.4993/acrt.18.28
[Show abstract][Hide abstract] ABSTRACT: Chronotherapy is one of the most active treatment schedule, based on the adjustment of drug delivery to the 24-hour rhythms generated by circadian rhythm. The aim of this study is to confirm that the efficacy of 5-fluorouracil (5-FU) is dependent on circadian rhythm, using Walker-256 xenografted rat. The present study demonstrated that tumor developed more rapidly at night rather than at day. Moreover, the administration of 5-FU at night was more effective rather than that at day. Furthermore, the microvessel count by immunohistochemical staining of endothelial cells revearled that tumors treated with 5-FU at night contained significantly less microvessels than those at day. In conclusion, our present data suggested that chronotherapy would contribute to the improvement of chemotherapy in patients with some population of malignancy through the control of angiogenesis.
Annals of Cancer Research and Therapy 01/2010; 18(1):43-46. DOI:10.4993/acrt.18.43
[Show abstract][Hide abstract] ABSTRACT: Adipocyte lines are a useful tool for adipocyte research. Recently, a new preadipocyte line designated AP-18 was established from subcutaneous tissue of the C3H/He mouse. In this study, we further characterized AP-18 cells. Adipocyte differentiation was assessed by accumulation of fat droplets stained by Oil Red O. The expression of the preadipocyte- or adipocyte-specific genes and adipocytokine genes was analysed qualitatively by RT-PCR and quantitatively by real-time PCR in comparison with the LM cell, a murine fibroblast line, and the 3T3-L1 cell, respectively. AP-18 cells were fibroblastoid in maintenance culture. After the confluence, fat droplets were accumulated in 50-60% of the cells cultured in the medium alone and in 70-90% of the cells cultured with insulin within 2 to 3 weeks. The fat accumulation was not promoted by the addition of dexamethazone, IBMX (3-isobutyl-1-methylxanthine) or troglitazone in combination with insulin, which were obligatory for differentiation of the 3T3-L1 cell, a murine preadipocyte line. Throughout the differentiation, AP-18 cells expressed Pref-1, LPL, C/EBP beta, C/EBP delta, RXR alpha, C/EBP alpha, PPAR gamma, RXR gamma, aP2, GLUT4, SCD1, UCP2, UCP3, TNFalpha, resistin, leptin, adiponectin and PAI-1 genes, but not the UCP1 gene, indicating that the cell is derived from WAT (white adipose tissue). The time course of these gene expressions was similar to that of 3T3-L1 cells, although the expressions were slower and lower in AP-18 cells. These data indicate that AP-18 cells are preadipocytes originated from WAT and differentiate into adipocytes under more physiological conditions than 3T3-L1 cells. AP-18 may be useful in adipocyte research.
Cell Biology International 11/2009; 34(3):293-9. DOI:10.1042/CBI20090063 · 1.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent studies implicate circadian genes in the regulation of cell cycle, apoptosis, and cell proliferation at a molecular level. These genesey affect cancer incidence, prognosis, and chemosensitivity. In this study, we measured the expression levels of clock genes and correlated their expression levels with clinicopathological parameters in epithelial ovarian cancer.
The expression levels of core clock genes, per1, per2, per3, cry1, cry2, Bmal1, clock, and CKIepsilon were quantified by real-time quantitative Reverse transcription-polymerase chain reaction in 83 ovarian cancer tissues and 11 normal ovarian tissues.
The expression levels of per1, per2, cry2, clock, CKIepsilon in ovarian cancers were significantly lower than those in normal ovaries. In contrast, cry1 expression was highest among the eight examined clock genes, followed by per3 and Bmal1. Cry1 expression was much higher in cancer than that in normal ovaries. Localized circadian gene expression was determined in cancer cells by in situ hybridization analysis. Cry1 expression was significantly reduced in mucinous and grade 3 tumors. Bmal1 expression was also significantly reduced in mucinous adenocarcinomas as compared to other histologies. In a multivariate analysis, the combination of low cry1 expression and low Bmal1 expression was an independent prognostic factor, as well as stage and histological subtype.
The antiphase expression of cry1 and Bmal1 may be preserved in ovarian cancers. The combination of cry1 and Bmal1 expression might become a possible prognostic marker in epithelial ovarian cancer.
[Show abstract][Hide abstract] ABSTRACT: Phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine (PC) to generate phosphatidic acid (PA) and choline. PA acts as a second messenger in cell proliferation; therefore PLD is believed to play an important role in carcinogenesis. PLD activity has been reported to be elevated in human breast, gastric, renal cell and colorectal carcinomas, compared with adjacent non-neoplastic tissues. The activity of PLD was also correlated with nuclear grade in breast cancer, tumor size in gastric carcinoma, and nodal involvement and deeper invasion in colorectal carcinoma. However, the number of cases in each study was small. The aim of this study was to investigate the expression level of PLD2 and its association with clinicopathological features in human colorectal carcinoma. Ninety-seven colorectal carcinomas were obtained from surgery. Expression level of PLD2 was assessed by real-time PCR. The prognostic relevance of PLD2 expression level in patients with colorectal carcinoma was also analyzed by the survival analysis of mortality follow-up data covering the period 2000-2004. PLD expression level was varied from tumor to tumor. Expression level of PLD was significantly correlated with tumor size (P<0.05); it was independent of lymph node metastasis, extent of invasion, pathological classification, distant metastasis and Dukes' stage. PLD expression level was also significantly correlated with survival of patients with colorectal carcinoma (P<0.05). These findings suggested that PLD2 plays an important role in progression of colorectal carcinoma and that PLD2 could be a target for therapy in colorectal carcinoma.
[Show abstract][Hide abstract] ABSTRACT: Many physiological, biochemical, and behavioral processes are under circadian regulation, which is generated by an internal time-keeping mechanism referred to as biological clock. The regulators of circadian rhythm in human plasma have not been completely elucidated. Here we demonstrated that the isolated protein from human plasma, which down-regulated expression level of cry1 in Jurkat cells, was apoprotein H (ApoH). Further, mRNA expression level of ApoH indicated circadian rhythm in Jurkat cells. The concentration of ApoH was subject to circadian rhythm in human plasma. These experimental results suggested that ApoH may be one of the members of the regulator of circadian rhythm and that ApoH expression level was also dependent on circadian rhythm in Jurkat cells and in human plasma.
Biochemical and Biophysical Research Communications 09/2007; 360(2):418-22. DOI:10.1016/j.bbrc.2007.06.061 · 2.30 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Pulmonary alveolar microlithiasis is an autosomal recessive disorder in which microliths are formed in the alveolar space.
To identify the responsible gene that causes pulmonary alveolar microlithiasis.
By means of a genomewide single-nucleotide polymorphism analysis using DNA from three patients, we have narrowed the region in which the candidate gene is located. From this region, we have identified a gene that has mutations in all patients with pulmonary alveolar microlithiasis.
We identified a candidate gene, SLC34A2, that encodes a type IIb sodium phosphate cotransporter and that is mutated in six of six patients investigated. SLC34A2 is specifically expressed in type II alveolar cells, and the mutations abolished the normal gene function.
Mutations in the SLC34A2 gene that abolish normal gene function cause pulmonary alveolar microlithiasis.
American Journal of Respiratory and Critical Care Medicine 03/2007; 175(3):263-8. DOI:10.1164/rccm.200609-1274OC · 13.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A 71-year-old woman was seen at our hospital because of abdominal fullness and dyspnea. Examinations revealed a tumor in the pelvis with fluid collection and dissemination was seen in the abdomen and chest. Moreover, hyaluronate in ascites rose to 20,000 mg/dl. Finally, by cytology of ascites using immunohistochemistry, the patient was diagnosed as malignant peritoneal mesothelioma with disseminations in the abdomen and chest. After intraperitoneal administration of 25 mg of cisplatin (CDDP), we started carboplatin (CBDCA) plus paclitaxel (PTX) combination chemotherapy (each treatment course consisted of 100 mg of PTX and 400 mg of CBDCA on day 1 and PTX 100 mg on day 8 and day 15 by intravenous administration followed by 2 drug-free weeks). After the sixth course, a complete remission was observed. Malignant mesothelioma is known to have a poor prognosis. However, we successfully treated malignant peritoneal mesothelioma with CBDCA and PTX combined chemotherapy. Our case suggests that we could improve the prognosis of malignant mesothelioma by aggressive chemotherapy.
Gan to kagaku ryoho. Cancer & chemotherapy 08/2006; 33(7):1001-4.
[Show abstract][Hide abstract] ABSTRACT: The authors identified a patient with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), who completely fulfilled the clinical criteria with low thymidine phosphorylase (TP) activity. However, the same homozygotic S471L TP gene mutation was also found in her unaffected mother, but with normal TP activity. To elucidate the pathogenesis of MNGIE, we performed the analysis below.
We analyzed the TP gene mutation in the proband and 145 unrelated individuals by direct sequence and restriction fragment length polymorphism (RFLP). TP activity was determined by the spectrophotometric method for each TP S471L genotype.
Among 145 normal persons, the S471L homozygote mutants were identified in 2.76% and their enzyme activity was normal.
TP gene mutation is not a primary cause of MNGIE, but with a mitochondrial deletion mutation, a single nucleotide polymorphism (SNP) of the TP gene may be crucial in the pathogenesis of MNGIE.
Internal Medicine 02/2006; 45(7):443-6. DOI:10.2169/internalmedicine.45.1371 · 0.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Copper-transporting P-type adenosine triphosphate (ATP7B) has been reported to be associated with cisplatin resistance in vitro. However, the clinical significance of this transporter has not previously been addressed in endometrial carcinoma. Our goal was to investigate if ATP7B is expressed in endometrial carcinoma and whether its expression correlates with prognosis.
We performed immunohistochemical analysis of ATP7B using a monoclonal antibody against ATP7B in 51 endometrial endometrioid adenocarcinomas. 27 of 51 patients were treated with cisplatin-based chemotherapy after surgery.
Cytoplasmic staining of tumor cells was observed in 37.3% (19/51 cases) of the analyzed carcinomas and no staining was observed in adjacent non-neoplastic cells. ATP7B positivity in the degree of differentiation of G2 and G3 carcinoma was significantly higher than that of G1 carcinoma (P = 0.019). The patients with ATP7B-positive tumors had a worse prognosis than that with ATP7B-negative tumors in overall survival and disease-free survival, respectively (P < 0.01).
These findings suggest that overexpression of ATP7B expression in endometrial carcinoma is correlated with unfavorable clinical outcome in patients treated with cisplatin-based chemotherapy. ATP7B expression could be considered as a prognostic factor in patients with endometrial carcinoma.
[Show abstract][Hide abstract] ABSTRACT: Despite the significance of tumor angiogenesis and the extensive knowledge on the molecular basis of blood vessel formation in carcinoma of colorectum, no data exist in hyperplastic polyp. This prompted us to examine angiogenesis in hyperplastic polyp. Eleven small hyperplastic polyps, 13 large hyperplastic polyps and their adjacent normal mucosas were included in this study. Angiogenesis was assessed by immunohistochemistry using monoclonal antibody against CD34. Angiogenic factor, thymidine phosphorylase was also examined by immunohistochemistry. Intra-tumoral microvessel density (IMD) in large hyperplastic polyp was significantly higher than that in small hyperplastic polyp (P<0.01) and that in normal mucosa (P<0.01). DAD in small hyperplastic polyp was also significantly higher than that in normal mucosa (P<0.01). Expression of dThdPase was almost observed in stromal cells in normal, small and large hyperplastic polyp. In addition, the proportion of the stromal cells expressing dThdPase in large hyperplastic polyp was significantly higher than that in small hyperplastic polyp and normal tissue (P<0.01, respectively). The proportion of the stromal cells expressing dThdPase in small hyperplastic polyp was significantly higher than that in normal tissue (P<0.01). The present study provides that angiogenesis may have an important role(s) in the development of hyperplastic polyp and dThdPase in stromal cells may support angiogenesis in hyperplastic polyp. Anti-angiogenic therapy might be available for suppression of hyperplastic polyp.
Cancer letters 03/2005; 218(2):223-8. DOI:10.1016/S0304-3835(03)00183-6 · 5.62 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Translational research (TR) involves both the development of novel diagnostics and novel therapeutics. These two major developmental areas are often associated with each other and these associations often bring new paradigms in the management of cancer patients. For example, the development of trastuzumab-based treatments has been conducted in harmony with the development of new methodologies to assess the expression of the Her-2 gene or protein, and from this, a therapeutic modality was established for breast cancer patients as a novel and individualized treatment system. TR covers a broad spectrum, from diagnosis to treatment, and it seems to act as a catalyst for developing novel paradigms. Therefore, it is crucial to conduct TR in clinical trials, in particular, prospective clinical trials. In this regard, TR can accelerate the development of new methodologies and increase trial efficiency. In this review, we describe the importance of TR, particularly that related to novel therapeutics.
Breast Cancer 02/2005; 12(2):86-90. DOI:10.2325/jbcs.12.86 · 1.59 Impact Factor