Dose escalation phase of a phase I/II study of GTI-2501, an antisense to the R1 subunit of ribonucleotide reductase (RNR) and docetaxel in patients with metastatic hormone-refractory prostate cancer

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Background: GTI-2501 (GTI) is a 20-mer oligonucleotide that is complementary to the R1 subunit of the RNR mRNA. The R1 protein is overexpressed in multiple tumour cell lines. GTI displays anti-tumour activity against prostate cancer xenografts in mice as a single agent and in combination with mitoxantrone. GTI also adds to the anti-tumour efficacy of taxanes in breast cancer xenografts in mice. A Phase 1 study of a 14 day continuous infusion of GTI in patients with solid tumours showed no dose limiting toxicities at doses up to 210.9 mg/m2/day. The objective of this dose escalation phase of a phase I/II study was to define a safe phase II dose of GTI in combination with docetaxel (D) in men with metastatic hormone refractory prostate cancer (HRPC). Methods: Men with metastatic HRPC were enrolled at 3 centres in Canada. GTI was given as a 14d continuous IV infusion every 21d with D IV infusion started 2 hrs prior to the end of the GTI infusion. Planned dose escalation cohorts are summarized in table . Results: 13 men were enrolled to the 3 cohorts. All patients are evaluable for toxicity. There was one possible DLT - an episode of grade 4 neutropenia reported at cycle 2 day 1 in the highest dose cohort - but the duration of neutropenia could not be confirmed. 3 additional patients were accrued to that cohort with no DLTs. The most common gr 3/4 toxicity was attributable to D (10 pts with Gr 3/4 neutropenia). The observed incidence of Gr 3/4 neutropenia was expected since patients had weekly CBCs. Only 1 patient had febrile neutropenia. 11 pts had fatigue (4 Gr 3) related to D and /or GTI. Other GTI attributable adverse events were Gr 1/2 including transient rises in transaminases and PTT. The pharmacokinetic data which is summarized in the table will be presented in full at the meeting. Conclusions: GTI can be given safely at its highest planned dose with standard doses of D. A Phase II evaluation of the GTI + D combination is planned for men with HRPC.

[Table: see text]

[Table: see text]

Effects of Oral Administration of Insulin-Like Growth Factor-I on Circulating Concentration of Insulin-Like Growth Factor-I and Growth of Internal Organs in Weanling Mice

Insulin-like growth factor (IGF)-I is a polypeptide that mediates the growth-promoting action of growth hormone in postnatal animals. The present study was conducted to examine whether orally administered IGF-I would be absorbed into the general circulation and also whether ingested IGF-I would enhance the growth of whole body as well as internal organs, and tissues in 3-week-old ICR-strain female weanling mice. In experiment (Exp) 1, a total of 70 mice received IGF-I orally at 1 microg.g-1 in 0.2-ml PBS or the vehicle alone. Concentrations of IGF-I and glucose in heart blood were measured after killing 5 animals in each group every fourth hour during a 24-hour period. In Exp 2, a total of 40 mice received oral IGF-I administration at 1 microg.g-1 or vehicle every third day beginning from day 0 for a 13-day period. Half the animals were killed at day 7 and the other half at day 13. Weights of whole body and organs/tissues (small intestine, liver, thigh muscle, and brain) were measured every day and at slaughter, respectively. In Exp 1, following the oral IGF-I administration, serum IGF-I concentration increased at hour 4 (p<0.01) and returned to the hour 0 level by hour 8, whereas glucose concentration was lowest at hour 4 and returned to the hour 0 level by hour 16. In the PBS-fed group, neither IGF-I nor glucose concentration changed during the 24-hour period. In Exp 2, weight of small intestine increased (p<0.05) in response to the oral IGF-I, whereas weights of liver and thigh muscle of the IGF-I-fed group were greater (p<0.01) and tended to be greater (p=0.06), respectively, than those of the PBS-fed only at day 13. However, brain weight and serum concentrations of IGF-I and IGF-II were not affected by oral IGF-I administration. Results suggest that although orally administered IGF-I mainly acts at the intestine, a portion of ingested IGF-I is absorbed into the general circulation to enhance the growth of selective organs/tissues in weanling mice.

[Surgical repair of isolated anomalous origin of left pulmonary artery from the ascending aorta in a 2-month-old infant]

A 2-month-old infant was referred to our department for evaluation of a congestive heart failure. The chest X-ray showed an enlarged globular heart. Further work-up was consistent with an anomalous origin of left pulmonary artery (PA) from the ascending aorta. The patient underwent a corrective surgery using cardiopulmonary bypass. The left PA was arising 15 cm above the aortic annulus and coursed in the curved manner to the left, crossing the main PA where the media of both vessels were fused. The ligamentum arteriosus, running from the top of the main PA to the right aortic arch, was divided. The left PA was detached at its origin and anastomosed to the main PA. The anterior wall of the main PA, where the media was fused, was reinforced with polytetrafluoroethylene (PTFE) patch. An angiogram 6 months after operation showed a rapid antegrade flow to the left PA, and angiographically normal luminal contour.

High-dose sequential chemotherapy followed by autologous stem cell transplantation in relapsed and refractory aggressive non-Hodgkin's lymphoma: results of a multicenter phase II study

BACKGROUND

Combination chemotherapy can cure patients with non-Hodgkin's lymphoma (NHL), but those who suffer treatment failure or relapse still have a poor prognosis. High-dose chemotherapy (HDCT) with autologous stem cell transplantation (ASCT) can improve the outcome of these patients. We evaluated an intensified high-dose sequential chemotherapy program with a final myeloablative course.

PATIENTS AND METHODS

Inclusion criteria were age 18-65 years, histologically proven primary progressive or relapsed aggressive NHL and eligibility for HDCT. The therapy consists of two cycles DHAP: dexamethasone 40 mg (day 1-4), high-dose cytarabine 2 g/m2 12q (day 2), cisplatin 100 mg/m2 (day 51); patients with partial (PR) or complete remission (CR) received cyclophosphamide 4 g/m2 (day 37), followed by peripheral blood stem cell (PBSC) harvest; methotrexate 8 g/m2 (day 1) plus vincristine 1.4 mg/m2 (day 51); and etoposide 500 mg/m2 (day 58-62). The final myeloblative course was BEAM: cytarabine 200 mg/m2 12q (day 81-84), etoposide 150 mg/m2 12q (day 81-84), melphalan 140 mg/m2 (day 80), carmustin 300 mg/m2 (day 80) followed by PBSCT.

RESULTS

Fifty-seven patients (median age 43 years, range 24-65) were enrolled: 23 (40%) patients were refractory to primary therapy and 34 (60%) patients had relapsed NHL. The response rate (RR) after 2 cycles of DHAP was 72% (9% CR, 63% PR) and at the final evaluation (100 days post transplantation) 43% (32% CR, 11% PR). Toxicity was tolerable. Median follow-up was 25 months (range 1-76 months). Freedom from second failure (FF2F) and overall survival (OS) at 2 years were 25% and 47% for all patients, respectively. FF2F at 2 years for patients with relapse and for patients refractory to primary therapy were 35% and 9% (P=0.0006), respectively. OS at 2 years for patients with relapse and for patients refractory to primary therapy were 58% and 24% (P=0.0044), respectively.

CONCLUSIONS

We conclude that this regimen is feasible, tolerable and effective in patients with relapsed NHL. In contrast, the results in patients with progressive disease are unsatisfactory. This program is currently being modified by addition of rituximab for patients with relapsed aggressive NHL.

Expression and relationship of the insulin-like growth factor system with posthatch growth in the Korean Native Ogol chicken

Insulin-like growth factors (IGF) act as regulators that modulate proliferation and differentiation of various cells. Also, IGF are involved in metabolism and body growth by regulating the synthesis and degradation of glycogen and proteins in animals. However, the effect of IGF system on body growth in poultry including Korean Native Ogol chickens (KNOC) has not been thoroughly studied. Therefore, this study was performed to investigate the expressions of IGF system and the relationship of IGF with body growth during posthatch growth in KNOC. Sera and organs were collected at hatch and at 1, 3, 5, and 7 wk. The mRNA expressions of IGF, IGF-I receptor, and IGF binding protein (IGFBP)-2 were quantitatively analyzed by reverse transcription (RT)-PCR. The IGF concentrations were measured by heterologous RIA, and the expression of IGFBP-2 was detected by Western ligand blotting. The body weight of KNOC rapidly increased during the experimental period, and increase in breast muscle weight was 5-fold from 1 to 3 wk. Although the circulating IGF-I concentration gradually increased, the level of IGF-I in breast muscle rapidly declined during growth period. The IGF-II expression was not similar to IGFBP-2 during postnatal growth. Moreover, the breast muscle IGF-II concentration was mainly correlated with body growth at 7 wk and breast muscle IGF-I at 1 and 5 wk. Taken together, the present study suggested that the endocrine manner of IGF-I was more important than auto/paracrine actions in body growth of KNOC and that expression of IGF-II was involved in body growth and IGF-I during posthatch growth of KNOC.

Relationship between egg productivity and insulin-like growth factor-I genotypes in Korean native Ogol chickens

Endocrine factors, such as steroid hormones and growth factors, regulate egg productivity in terms of the quantity of egg production, egg weight, sexual maturity, and the number of small yellow follicles (SYF). Insulin-like growth factors (IGF) are involved in the regulation of ovulation rate and ovarian follicular development in chickens, and a relationship between IGF-I genotype and egg weight has been reported. However, the effect of IGF on egg productivity in Korean Native Ogol chickens (KNOC) has been little studied. Therefore, this study was conducted to identify the relationship among endocrine factors (IGF-I, IGF-II, estradiol, and progesterone), IGF-I genotypes, and egg productivity. Frequencies of IGF-I genotypes (AA, AB, BB) were 17.3, 26.9, and 55.8%, respectively, within a population. When compared with the IGF-I genotypes, the AB genotype had the highest serum levels of estradiol and progesterone at 40 and 30 wk of age, respectively; the highest IGF-II concentration in F1 follicles at 60 wk; and was positively associated with the number of SYF at 60 wk. The results showed that the A allele was associated with a higher IGF-II expression in the follicles and stimulated the development of follicles, indicating a positive association of the A allele with egg production and the number of SYF. Therefore, these results suggest that there is a possibility of IGF-I genotypes acting as a genetic marker for egg productivity of KNOC.

Challenges to environmental toxicology and epidemiology: where do we stand and which way do we go?

Modern toxicology investigates a wide array of both old and new health hazards. Priority setting is needed to select agents for research from the plethora of exposure circumstances. The changing societies and a growing fraction of the aged have to be taken into consideration. A precise exposure assessment is of importance for risk estimation and regulation. Toxicology contributes to the exploration of pathomechanisms to specify the exposure metrics for risk estimation. Combined effects of co-existing agents are not yet sufficiently understood. Animal experiments allow a separate administration of agents which can not be disentangled by epidemiological means, but their value is limited for low exposure levels in many of today's settings. As an experimental science, toxicology has to keep pace with the rapidly growing knowledge about the language of the genome and the changing paradigms in cancer development. During the pioneer era of assembling a working draft of the human genome, toxicogenomics has been developed. Gene and pathway complexity have to be considered when investigating gene-environment interactions. For a best conduct of studies, modern toxicology needs a close liaison with many other disciplines like epidemiology and bioinformatics.

Reliability of non-invasively acquired human genomic DNA as a substrate for real-time PCR-assisted analysis of genetic polymorphisms

Molecular epidemiological studies require high numbers of participants. The combination of an non-invasive access to human DNA with a rapid genotyping analysis, e.g. by use of LightCycler assisted real-time polymerase chain reaction (PCR), can be helpful in conducting such trials. The aim of our study was to define, for the first time, the use of LightCycler technology in analysis of non-invasively derived DNA. DNA extracted from blood, mouthwash and buccal cytobrush samples from 100 volunteers was analyzed for the genotypes of cytochrome P450 CYP1B1, and glutathione S-transferases GSTT1, GSTM1 and GSTP1. The median amounts of DNA isolated from blood, mouthwash and buccal cytobrush samples were 95, 11 and 8 microg, respectively. While genotyping for CYP1B1 codon 432 polymorphism and GSTP1 codon 105 polymorphism resulted in a complete correspondence for all three modes of sampling, the identification of individuals with null-genotype for GSTT1 or GSTM1 failed in some cases due to atypical courses of the corresponding melting curves, leading to high false-positive rates in the group of non-invasively derived samples. Thus, the results presented here call for caution in using LightCycler assisted real-time PCR in non-invasively collected samples, at least when appropriate control strategies are not implemented.

Delayed-onset pineal abscess following transsphenoidal surgery for pituitary adenoma: a case report

A 41-year-old woman suffered fever, speech disturbance and confusion four months after transsphenoidal surgery for pituitary macroadenoma. Meanwhile, the patient had been well except for transient asymptomatic postoperative pneumocephalus without cerebrospinal fluid (CSF) rhinorrhoea. Brain computed tomographic scan revealed a peripherally enhancing pineal abscess which superimposed on a preexisting pineal cyst. CSF findings showed elevated leukocyte count and positive bacterial culture. Three weeks of intensive antibiotic therapy and surgical evacuation of the pineal abscess ensued. The patient showed restricted postoperative recovery with moderate hypothalamic dysfunction. A unique case of delayed-onset postoperative pineal abscess which complicates the preexisting asymptomatic pineal cyst is presented and the possible explanation for this is speculated with review of the available literatures.