Construction and validation of a scoring system to predict resistance to chemotherapeutic drugs using gene expression profiles in canine lymphoma.

The present study aimed to verify the changes in the expression levels of 13 candidate genes associated with chemotherapy resistance and to construct a scoring system to predict resistance to these drugs. The expression levels of the 13 candidate genes were compared between 20 dogs with lymphoma that were sensitive to drugs used in CHOP-based protocol and 16 dogs with lymphoma that were resistant to these drugs. The expression levels of six genes; ASNS, CCR3, CALCA, FCER1A, LOC448801, and EDNRB were significantly different between the two groups. A scoring system to predict resistance to cyclophosphamide, doxorubicin and vincristine, which are used in CHOP-based protocol, was constructed based on expression levels of the six genes in these 36 dogs using logistic regression models. After internal validation, sensitivity and specificity of the scoring system were 0.759 and 0.853, respectively. External validation was conducted in another cohort of 33 dogs with lymphoma, and sensitivity and specificity of the scoring system were 0.800 and 0.696, respectively. In conclusion, this study identified six genes associated with resistance to drugs used in CHOP-based protocol in canine lymphoma and proposed a novel scoring system to predict resistance to these drugs. This system might be beneficial in selecting the most appropriate chemotherapy protocol for individual dogs with lymphoma.

Clinical relevance of EMT and stem-like gene expression in circulating tumor cells of metastatic colorectal cancer patients.

Using approved methods, circulating tumor cells (CTCs) are only isolated from blood in 30%-50% of metastatic colorectal cancer (mCRC) patients. We previously validated a technique to isolate circulating tumor cells (CTCs) in a cohort of mCRC patients by combining immunomagnetic enrichment of EpCAM+/CD45- cells with qRT-PCR amplification of CK20 and survivin expression. Here, we examined the prognostic utility of CTC epithelial-mesenchymal transition (EMT) and stem cell gene expression. An 8 ml blood sample was collected from 78 consecutive mCRC patients before treatment with investigational and standard chemotherapeutics. The mRNA expression of EMT (PI3Kα, Akt-2, Twist1) and stem cell (ALDH1) markers was measured. Associations between CTC gene expression and progression-free survival (PFS) and overall survival (OS) were determined using Cox regression models. Among patients without CK20 or survivin-expressing CTCs (n=17), 55% had expression of ALDH1, PI3Kα and/or Akt-2. Patients with positive CTC Akt-2 expression had a significantly shorter median PFS (3.0 versus 4.0 months) compared with those without CTC Akt-2 expression in univariable (hazard ratio (HR)=1.61; log-rank P=0.034) and multivariable analyses (HR=1.70; adjusted P=0.041). In univariable analysis, CTC ALDH1 expression was associated with shorter OS (10.0 versus 38.6 months; HR=2.04, P=0.021). Patients with CTCs expressing ALDH1, PI3Kα and/or Akt-2 had a significantly inferior PFS (3.0 versus 7.7 months; HR=1.88, P=0.015) and OS (10.0 versus 26.8+ months; HR=2.25, P=0.050) in univariable, but not multivariable, analysis. CONCLUSIONS: CTC Akt-2 expression may serve as a clinically useful prognostic marker in mCRC patients and warrants further evaluation in prospective trials.

Impact of genetic variations in the MAPK signaling pathway on outcome in metastatic colorectal cancer patients treated with first-line FOLFIRI and bevacizumab: data from FIRE-3 and TRIBE trials.

BACKGROUND: The MAPK-interacting kinase 1 (MKNK1) is localized downstream of the RAS/RAF/ERK and the MAP3K1/MKK/p38 signaling pathway. Through phosphorylation MKNK1 regulates the function of eukaryotic translation initiation factor 4E, a key player in translational control, whose expression is often upregulated in metastatic colorectal cancer patients (mCRC). Preclinical data suggest that MKNK1 increases angiogenesis by upregulating angiogenic factors. We therefore hypothesize that variations in the MKNK1 gene predict outcome in mCRC patients treated with first-line FOLFIRI and bevacizumab (bev). PATIENTS AND METHODS: A total of 567 patients with KRAS wild-type mCRC in the randomized phase III FIRE-3 and TRIBE trials treated with first-line FOLFIRI/bev (discovery and validation cohorts) or FOLFIRI and cetuximab (cet) (control cohort) were included in this study. Five single-nucleotide polymorphisms in the MAPK signaling pathway were analyzed. RESULTS: AA genotype carriers of the MKNK1 rs8602 single-nucleotide polymorphism treated with FOLFIRI/bev in the discovery cohort (FIRE-3) had a shorter progression-free survival (PFS) than those harboring any C (7.9 versus 10.3 months, Hazard ratio (HR) 1.73, P = 0.038). This association could be confirmed in the validation cohort (TRIBE) in multivariable analysis (PFS 9.0 versus 11.0 months, HR 3.04, P = 0.029). Furthermore, AA carriers in the validation cohort had a decreased overall response rate (25% versus 66%, P = 0.049). Conversely, AA genotype carriers in the control group receiving FOLFIRI/cet did not show a shorter PFS. By combining both FOLFIRI/bev cohorts the worse outcome among AA carriers became more significant (PFS 9.0 versus 10.5 months) in univariable (HR 1.74, P = 0.015) and multivariable analysis (HR 1.76, P = 0.022). Accordingly, AA carriers did also exhibit an inferior overall response rate compared with those harboring any C (36% versus 65%, P = 0.005). CONCLUSION: MKNK1 polymorphism rs8602 might serve as a predictive marker in KRAS wild-type mCRC patients treated with FOLFIRI/bev in the first-line setting. Additionally, MKNK1 might be a promising target for drug development.

Genetic variants of DNA repair-related genes predict efficacy of TAS-102 in patients with refractory metastatic colorectal cancer.

Background: Tri-phosphorylated trifluridine (FTD) incorporation into DNA is TAS-102's main anti-tumor action. We tested whether genetic polymorphisms in homologous recombination (HR) and cell cycle checkpoint pathway for DNA repair is associated with outcomes in refractory metastatic colorectal cancer (mCRC) patients treated with TAS-102. Patients and methods: We analyzed genomic DNA extracted from 233 samples of three cohorts: an evaluation cohort of 52 patients receiving TAS-102, a validation cohort of 129 patients receiving TAS-102 and a control cohort of 52 patients receiving regorafenib. Single nucleotide polymorphisms of genes involved in HR (ATM, BRCA1, BRCA2, XRCC3, FANCD2, H2AX, RAD51) and cell cycle checkpoint (ATR, CHEK1, CHEK2, CDKN1A, TP53, CHE1, PIN1, PCNA) were analyzed by PCR-based direct sequencing. Results: In univariate analysis for the evaluation cohort, patients with any G allele in ATM rs609429 had longer overall survival (OS) than those with the C/C variant (8.7 vs. 4.4 months, HR 0.37, 95% CI: 0.14-0.99, P = 0.022). Patients carrying any A allele in XRCC3 rs861539 had significantly longer progression-free survival (PFS) (3.8 vs. 2.3 months, HR 0.44, 95% CI: 0.21-0.92, P = 0.024) and OS (15.6 vs. 6.3 months, HR 0.25, 95% CI: 0.08-0.79, P = 0.012) than those with the G/G variant. In multivariable analysis, ATM rs609429 remained significant for OS (P = 0.020). In the validation cohort, patients having ATM rs609429 with any G allele showed longer OS and PFS; the G/A variant in XRCC3 rs861539 showed longer OS, though without statistical significance. Conclusion: Genetic variants in the HR pathway may predict clinical outcome in mCRC patients receiving TAS-102.

Upper-extremity deep vein thrombosis related to central venous port systems implanted in cancer patients.

The purpose of the current study was to evaluate the incidence and course of upper-extremity deep vein thrombosis (UEDVT) related to an implanted central venous port (CV-port) system in cancer patients. From July 2007 to July 2008, 92 consecutive patients who underwent implantation of a CV-port for chemotherapy for colorectal cancer were prospectively enrolled in the study. All patients were examined at prescribed intervals by ultrasonography (US) to estimate the incidence of catheter-related venous thrombosis. We categorised ultrasound diagnosis into three types: Type 0, no thrombus; Type I, thrombi around catheter without obstruction of venous flow; Type II: thrombi with obstruction of venous flow. Upon initial ultrasound examination, 25 cases (27%) were categorised as Type 0, 64 (70%) as Type I and III (3%) as Type II. Of the 64 Type-I cases, 4 cases worsened to Type II within a month, and 3 others (including 1 patient who developed pulmonary embolism) became Type II after 1 month. Of the other Type-I cases, 12 cases improved to Type 0 and 45 cases remained Type I. All 10 patients categorised as Type II underwent anticoagulant therapy and resumed their chemotherapy without exacerbations of thrombosis. In cancer patients undergoing long-term chemotherapy, there is an unexpectedly high prevalence of catheter-related UEDVT, which can be detected by ultrasound at an early stage after implantation of a CV-port. Given that cancer patients with UEDVT may have worse outcomes than those without, clinicians should consider careful monitoring for UEDVT and introducing anticoagulant therapy.

Metastin suppresses the motility and growth of CHO cells transfected with its receptor.

We recently reported having identified of the ligand for an orphan G-protein-coupled receptor, hOT7T175, as the gene product (68-121)-amide of the metastasis suppressor gene KiSS-1. We further showed that the ligand, which we named "metastin," inhibits chemotaxis and invasion of Chinese hamster ovary (CHO) cells transfected with hOT7T175 cDNA (CHO/h175) in vitro, and pulmonary metastasis of hOT7T175-transfected B16-BL6 melanomas in vivo. In the present study, we investigated the activity of metastin in CHO/h175 cells in greater detail. Metastin significantly suppressed motility in a chemotaxis assay and wound healing assay at 10-100 nM order concentrations. Two N-terminally truncated peptides, metastin(40-54) and metastin(45-54) inhibited the migration of CHO/h175 cells as potently as metastin itself. Metastin also inhibited the spreading, monolayer growth and colony formation in agar (0.8%) of CHO/h175 cells at 10-100 nM concentrations. These results indicate that metastin is a potent inhibitor of cell motility, leading to suppression of cell growth and antimetastatic activity, and suggest that low molecular chemical compounds could replace its activity as a novel antimetastatic agent.

Novel betacellulin derivatives. Separation of the differentiation activity from the mitogenic activity.

Betacellulin (BTC) is a member of the epidermal growth factor family. It has two biological activities: mitogenic activity in fibroblasts and vascular smooth muscle cells, and differentiation activity for the differentiation of pancreatic acinar AR42J cells into insulin-secreting cells. The previous finding that recombinant BTC promotes the neogenesis of beta-cells in a mouse model supports the possibility that BTC is a therapeutic protein. However, the mitogenic activity of BTC may not be needed for differentiation into beta-cells and may cause a side effect in clinical use. We prepared several derivatives of BTC to segregate the two activities, to decrease the mitogenic activity, and to maintain the differentiation activity. We succeeded in obtaining BTC derivatives segregated by the two biological activities by preparing truncated-type derivatives. A derivative of BTC, BTC24-76, with a truncated N-terminal 23 amino acids and C-terminal 4 amino acids, was 2.5-fold more active in differentiation and had one-tenth of the mitogenic activity. The derivatives described in the present study should be helpful in future applications as therapeutic proteins and in basic research for discovery of a BTC-specific receptor.

Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor.

Metastasis is a major cause of death in cancer patients and involves a multistep process including detachment of cancer cells from a primary cancer, invasion of surrounding tissue, spread through circulation, re-invasion and proliferation in distant organs. KiSS-1 is a human metastasis suppressor gene, that suppresses metastases of human melanomas and breast carcinomas without affecting tumorigenicity. However, its gene product and functional mechanisms have not been elucidated. Here we show that KiSS-1 (refs 1, 4) encodes a carboxy-terminally amidated peptide with 54 amino-acid residues, which we have isolated from human placenta as the endogenous ligand of an orphan G-protein-coupled receptor (hOT7T175) and have named 'metastin'. Metastin inhibits chemotaxis and invasion of hOT7T175-transfected CHO cells in vitro and attenuates pulmonary metastasis of hOT7T175-transfected B16-BL6 melanomas in vivo. The results suggest possible mechanisms of action for KiSS-1 and a potential new therapeutic approach.

Phase I study of second-line chemotherapy with docetaxel and carboplatin in advanced non-small-cell lung cancer.

PURPOSE: Docetaxel and carboplatin have a broad spectrum of antitumor activity. We conducted a phase I study of docetaxel and carboplatin as second-line chemotherapy in previously treated non-small-cell lung cancer (NSCLC). This study aimed to determine the maximum tolerated dose (MTD) and the dose-limiting toxicities in this second-line combination chemotherapy. METHODS: Patients with advanced NSCLC were treated with escalating docetaxel doses in combination with a fixed-target area under the concentration-time curve (AUC) of 5 mg min/ml of carboplatin on day 1 of a 3-4-week cycle. The carboplatin dose was determined by multiplying the AUC by the clearance predicted using the Chatelut formula. The docetaxel dose was escalated from 40 mg/m2 to the MTD by 10 mg/m2 increments. RESULTS: A total of 16 patients previously treated with anticancer drugs were enrolled through three dose levels (40, 50 and 60 mg/m2 of docetaxel). All patients were assessable for toxicity and response. The MTD was docetaxel 60 mg/m2 with a carboplatin target AUC of 5 mg min/ml, and the dose-limiting toxicities in two of four patients were neutropenia and thrombocytopenia. Overall, neutropenia and thrombocytopenia of grade 3/4 occurred in eight patients (50%) and three patients (19%), respectively. Four patients (25%) and two patients (13%) experienced both grade 1 diarrhea and dermatitis, respectively. Allergic reactions, fluid retention, pneumonitis, neurotoxicity and mucositis were not observed. Of 16 patients, 5 showed an objective response (response rate 31%; 95% CI 14-56%). CONCLUSIONS: The combination of docetaxel and carboplatin is a feasible and well-tolerated second-line chemotherapy regimen in the treatment of NSCLC. Docetaxel 50 mg/m2 under the carboplatin target AUC of 5 mg x min/ml using the Chatelut formula was the recommended dose for phase II study.

Birth cohort effects on incidence of lung cancers: a population-based study in Nagasaki, Japan.

Smoking prevalence remains high (around 60%) among Japanese males, but smoking initiation among males born in the 1930s decreased by approximately 10% due to economic difficulties following World War II. The present study was designed to examine whether this temporary decline in smoking initiation influenced the subsequent incidence of lung cancers, especially adenocarcinoma. Trends of lung cancer incidence by histological type in both sexes were investigated using data from the population-based cancer registry in Nagasaki, Japan, from 1986 through 1995. During this period, 5668 males and 2309 females were diagnosed as having lung cancer, and the overall incidence of lung cancers among both sexes remained stable. However, males aged 55 - 59 years showed a decrease in the age-specific incidence of adenocarcinoma and squamous-cell carcinoma (P < 0.05 and P < 0.01, respectively). In birth cohort analyses, the incidence of adenocarcinoma and squamous-cell carcinoma was lower in the 1935 - 1939 birth male cohort than in the successive cohorts. The incidence of lung cancers among females with low smoking prevalence did not change with birth cohort. The low smoking initiation among the 1935 - 1939 birth male cohort appeared to have resulted in a decreased incidence of adenocarcinoma and squamous cell carcinoma among middle-aged Japanese males. The present study suggests that smoking prevention has an effect in reducing the incidence of lung adenocarcinoma, as well as squamous-cell carcinoma, among smokers.

Interactions of ofloxacin and erythromycin with the multidrug resistance protein (MRP) in MRP-overexpressing human leukemia cells.

To investigate interactions between the multidrug resistance protein (MRP) and antimicrobial agents, we examined the effects of 12 agents on vincristine sensitivity and efflux of the calcein acetoxy-methyl ester (calcein-AM) of a MRP substrate in MRP-overexpressing cells. Only ofloxacin and erythromycin enhanced sensitivity with increased intracellular vincristine accumulation and inhibited the calcein-AM efflux. Our findings suggest that the two agents are possible MRP substrates and may competitively inhibit MRP function as a drug efflux pump.

Synthesis of new peptides with prolactin-releasing activity by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction.

A newly isolated peptide from bovine hypothalamus with prolactin-releasing activity (prolactin-releasing peptide; PrRP) was synthesized by a combination of recombinant DNA technology and a cysteine-specific cyanylation reaction, together with rat and human homologs. The peptides were expressed in the form of fusion proteins with basic fibroblast growth factor mutein, which were purified by heparin-affinity chromatography. The fusion proteins were cleaved at the cysteine residues of the junction site by cyanylation, followed by treatment with ammonia for C-terminal amidation. Purification of the resulting crude peptides was performed using chromatography on a gel-filtration column, a cation-exchange column, and a reversed-phase column. As an example, about 90 mg of bovine PrRP (bPrRP) was obtained from 201 of culture bloth. The purified b PrRP showed full biological activities in binding to its receptor expressed on CHO cells and releasing arachidonic acid metabolite from the same cells, while the C-terminal acid form of bPrRP had little of these activities. These results indicate that the C-terminal amide structure is very important for expressing biological activity. The peptides obtained here might be very useful for studies on their biological significance and roles in vivo.

Renaturation of recombinant human neurotrophin-3 from inclusion bodies using a suppressor agent of aggregation.

Escherichia coli has been widely used in the production of recombinant proteins. One of the drawbacks inherent in this method is that the proteins produced in the cells often form inactive inclusion bodies. Usually, the inclusion bodies can be separated from other cell components, solubilized by denaturants such as guanidine hydrochloride or urea, and then renatured through a refolding process such as dilution or dialysis. However, it has been shown that biologically active recombinant human neurotrophin-3 cannot be obtained at high yield by this procedure due to aggregation and precipitation of the protein. We applied the refolding process using the aggregation suppressor L-arginine in the renaturation of neurotrophin-3, and obtained biologically active neurotrophin-3 at high yield from the inclusion bodies. Consequently, about 10 mg of purified neurotrophin-3 was prepared from 1 litre of culture broth.

[Strategy for the treatment of hepatocellular carcinoma].

Hepatocellular carcinoma is a refractory cancer for the following two reasons: the tumor characteristics, including formation of tumor thrombus in the portal vein, metastasis within the liver and multicentricity of growth; and liver function disturbance due to cirrhotic change by B- or C-type viral infection. The most desirable treatment is hepatic resection, the only method producing a disease-free condition. However, there are not many cases that meet the indications for hepatic resection, since they have advanced lesions and/or liver dysfunction. If one cannot perform a hepatic resection, other suitable therapies should be selected, including transcatheter arterial embolization, percutaneous ethanol injection therapy, ligation of hepatic artery, irradiation, chemotherapy from hepatic artery via reservoir and so on. Combined therapy may sometimes be necessary for satisfactory efficacy. For long-term survival it is very important to do a close follow-up study over a long period. This encourages us to detect new lesions earlier and then perform suitable therapy again. Notifying patients of the disease and obtaining informed consent are needed for this long-term follow-up and treatment. When patients were examined who had first undergone hepatic resection and then hepatic re-resection for recurrence, we found that their survival rate was not different from that in the non-recurrent cases. This result indicates that overcoming refractory hepatocellular carcinoma requires a multidisciplinary treatment in which hepatic resection is the main means.

Regulation of pyrimidine nucleotide synthesis in rat hematopoiesis.

In an attempt to define a regulation of pyrimidine nucleotide synthesis in hematopoietic cells, we investigated the activities of thymidylate synthetase and thymidine kinase, and the cell cycle by flow cytometric DNA analysis and bromodeoxyuridine-immunohistochemistry during the recovery phase of hematopoietic cells in bone marrow after the hypoplastic period induced by cyclophosphamide treatment in rats. The hematopoietic cells first entered into cell cycle via the de novo pathway in pyrimidine nucleotide synthesis, and were secondly proliferated and differentiated via the salvage pathway. S-phase cells associated with a myeloid hematopoiesis increased earlier than those associated with an erythroid hematopoiesis in the recovery phase of in rat bone marrow.

Repeated hepatic resection for recurrent hepatocellular carcinoma in eighteen cases.

BACKGROUND: Although intrahepatic recurrence after hepatic resection for hepatocellular carcinoma is the most significant cause of death, very few reports are available for hepatic re-resection as a radical treatment for recurrence. METHODS: Eighteen patients who underwent repeated hepatic resections for hepatocellular carcinoma were evaluated. Most of the patients regularly received measurement of alpha-fetoprotein level once a month and examination by ultrasonography and/or computed tomography scanning once every 3 to 4 months. RESULTS: No operative deaths occurred. The alpha-fetoprotein levels of 9 of the 18 patients were within the normal range. Most patients underwent limited hepatic resection to maintain the remaining hepatic function. The 1-, 3-, and 5-year cumulative survival rates after repeated resection were 88%, 37%, and 37%, respectively. The 3-, 5-, and 7-year survival rates after the first resection were 88%, 68%, and 45%, respectively. These showed no significant difference from the survival rates of patients with no recurrences after hepatic resection. CONCLUSIONS: Careful follow-up examinations after hepatic resection are needed for early detection of recurrences, and efforts should be made for repeated hepatic resection, which leads to satisfactory outcome.

Effects of recombinant human erythropoietin on DNA synthesis in rat hematopoietic organs.

In an attempt to define the effects of recombinant human erythropoietin (rEPO) on DNA synthesis in hematopoietic organs, we investigated DNA-synthesizing enzyme activities, i.e., thymidylate synthetase and thymidine kinase activities, and bromodeoxyuridine-immunohistochemistry during the recovery phase of hematopoietic cells in bone marrow and spleen after the hypoplastic period induced by cyclophosphamide (Cy) treatment in rats. Treatment with rEPO increased enzyme activities and cell number of erythroid series in bone marrow cells; it also increased organ weight and S-phase cells in the spleen, followed by an augmentation of the number of erythrocytes and a rise in the hemoglobin and hematocrit levels in peripheral blood with or without Cy treatment.

Trisomy 4 in a case of acute myelogenous leukemia accompanied by subcutaneous soft tissue tumors. Report of a case and review of the literature.

We report a patient with acute myelogenous leukemia [AML, French-American-British classification (FAB) M2] with trisomy 4, who developed subcutaneous soft tissue tumors at the time leukemia was diagnosed. A review of the literature on AML with trisomy 4 suggests a relation between trisomy 4 and tumor formation of leukemic cells.