Citations

Emerging technologies have greatly expanded our ability to detect, characterize, and treat colorectal cancer. The Coalition of Cancer Cooperative Groups convened a multidisciplinary panel, the Scientific Leadership Council in GI cancer, to discuss and advise on the priorities and opportunities to advance current and future approaches into the clinical arena to impact most rapidly the morbidity and mortality from this disease. The Council's recommendations for research priorities are the result of engagement of community and academic oncologists, patient advocacy groups, and other stakeholders including the pharmaceutical industry and governmental agencies. We detail some key prospects for investigation in the areas of colon cancer detection, prevention, and surgical and medical management. Many are in early or definitive clinical trials, and a focus on rapid accrual is urged. The implementation of biology-directed laboratory investigations, both in association with ongoing clinical trials and as a separate developmental strategy for targeted therapies, is supported as the route to individualized therapy.

Purpose An increasing serum prostate-specific antigen (PSA) level is the initial sign of recurrent prostate cancer among patients treated with radical prostatectomy. Salvage radiation therapy (SRT) may eradicate locally recurrent cancer, but studies to distinguish local from systemic recurrence lack adequate sensitivity and specificity. We developed a nomogram to predict the probability of cancer control at 6 years after SRT for PSA-defined recurrence. Patients and Methods Using multivariable Cox regression analysis, we constructed a model to predict the probability of disease progression after SRT in a multi-institutional cohort of 1,540 patients. Results The 6-year progression-free probability was 32% (95% CI, 28% to 35%) overall. Forty-eight percent (95% CI, 40% to 56%) of patients treated with SRT alone at PSA levels of 0.50 ng/mL or lower were disease free at 6 years, including 41% (95% CI, 31% to 51%) who also had a PSA doubling time of 10 months or less or poorly differentiated (Gleason grade 8 to 10) cancer. Significant variables in the model were PSA level before SRT (P < .001), prostatectomy Gleason grade (P < .001), PSA doubling time (P < .001), surgical margins (P < .001), androgen-deprivation therapy before or during SRT (P < .001), and lymph node metastasis (P = .019). The resultant nomogram was internally validated and had a concordance index of 0.69. Conclusion Nearly half of patients with recurrent prostate cancer after radical prostatectomy have a long-term PSA response to SRT when treatment is administered at the earliest sign of recurrence. The nomogram we developed predicts the outcome of SRT and should prove valuable for medical decision making for patients with a rising PSA level.

AbstractPrevious studies suggest that enzymes involved in the androgen metabolic pathway are susceptibility factors for prostate cancer. Estrogen metabolites functioning as genotoxins have also been proposed as risk factors. In this study, we systematically tested the hypothesis that common genetic variations for those enzymes involved in the androgen and estrogen metabolic pathways increase risk for sporadic and familial prostate cancer. From these two pathways, 46 polymorphisms (34 single nucleotide polymorphisms, 10 short tandem repeat polymorphisms, and 2 null alleles) in 25 genes were tested for possible associations. Those genes tested included PRL, LHB, CYP11A1, HSD3B1, HSD3B2, HSD17B2, CYP17, SRD5A2, AKR1C3, UGT2B15, AR, SHBG, and KLK3 from the androgen pathway and CYP19, HSD17B1, CYP1A1, CYP1A2, CYP1B1, COMT, GSTP1, GSTT1, GSTM1, NQO1, ESR1, and ESR2 from the estrogen pathway. A case-control study design was used with two sets of cases: familial cases with a strong prostate cancer family history (n = 438 from 178 families) and sporadic cases with a negative prostate cancer family history (n = 499). The controls (n = 493) were derived from a population-based collection. Our results provide suggestive findings for an association with either familial or sporadic prostate cancer with polymorphisms in four genes: AKR1C3, HSD17B1, NQO1, and GSTT1. Additional suggestive findings for an association with clinical variables (disease stage, grade, and/or node status) were observed for single nucleotide polymorphisms in eight genes: HSD3B2, SRD5A2, SHBG, ESR1, CYP1A1, CYP1B1, GSTT1, and NQO1. However, none of the findings were statistically significant after appropriate corrections for multiple comparisons. Given that the point estimates for the odds ratio for each of these polymorphisms are &lt;2.0, much larger sample sizes will be required for confirmation. (Cancer Epidemiol Biomarkers Prev 2007;16(5):969–78)

Adjuvant chemotherapy has led to improvements in relapse-free and overall survival in patients with breast, colon, and non–small-cell lung cancer, yet many older patients are not offered these potentially life-saving treatments. Moreover, older patients have been either excluded or under-represented in most adjuvant trials, limiting the generalizability of these treatments to older populations. Limited data in elders suggest that older patients derive significant benefits from adjuvant therapies provided they have life expectancies exceeding 5 years. Making treatment decisions in elders is challenging. Many have major comorbidities that may substantially limit life expectancy and minimize or negate the benefits of adjuvant chemotherapy. In this review, we discuss the potential benefits of adjuvant treatment in older patients with solid tumors with a focus on general principles involved in the selection of adjuvant therapy for patients with breast, colon, and non–small-cell lung cancer. In addition, we discuss the role of comorbidity and how it factors in treatment decisions. Finally, we discuss future research directions and funding for elders with cancer.

Abstract Chronic lymphocytic leukemia (CLL) is commonly defined as a disease of failed apoptosis of B cells and remains an incurable disease. The mechanism of resistance to apoptosis in CLL is complex and influenced by numerous factors, including nuclear factor κB (NFκB)-mediated expression of antiapoptotic molecules. Recent evidence indicates that glycogen synthase kinase-3β (GSK-3β) positively regulates NFκB-mediated gene transcription and cell survival. Using malignant B cells collected from patients with CLL, we find that both GSK-3β and NFκB accumulate in the nucleus of CLL B cells, and pharmacologic inhibition of GSK-3 results in decreased expression of two NFκB target genes Bcl-2 and XIAP and a subsequent increase in CLL B-cell apoptosis ex vivo. Furthermore, we observed that inhibition of GSK-3 leads to a decrease in NFκB-mediated gene transcription but does not affect the nuclear accumulation of NFκB in CLL B cells. Last, using chromatin immunoprecipitation, we show that GSK-3 inhibition abrogates NFκB binding to its target gene promoters (XIAP, Bcl-2), in part through epigenetic modification of histones. Our results establish that inhibition of GSK-3 abrogates NFκB binding to its target gene promoters through an epigenetic mechanism, enhances apoptosis in CLL B cells ex vivo and identifies GSK-3 as a potential therapeutic target in the treatment of CLL.

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) infection causes apoptosis of infected CD4 T cells as well as uninfected (bystander) CD4 and CD8 T cells. It remains unknown what signals cause infected cells to die. We demonstrate that HIV-1 protease specifically cleaves procaspase 8 to create a novel fragment termed casp8p41, which independently induces apoptosis. casp8p41 is specific to HIV-1 protease-induced death but not other caspase 8-dependent death stimuli. In HIV-1-infected patients, casp8p41 is detected only in CD4 + T cells, predominantly in the CD27 + memory subset, its presence increases with increasing viral load, and it colocalizes with both infected and apoptotic cells. These data indicate that casp8p41 independently induces apoptosis and is a specific product of HIV-1 protease which may contribute to death of HIV-1-infected cells.

Abstract Background: Family-based linkage studies, association studies, and studies of tumors have highlighted human chromosome 8q as a genomic region of interest for prostate cancer susceptibility loci. Recently, a locus at 8q24, characterized by both a single nucleotide polymorphism (SNP) and a microsatellite marker, was shown to be associated with prostate cancer risk in Icelandic, Swedish, and U.S. samples. Although the data were provocative, the U.S. samples were not population based, which precludes assessment of the potential contribution of this locus to prostate cancer incidence in the United States. Methods: We analyzed both markers in a population-based, case-control study of middle-aged men from King County, Washington. Results: Overall, there was a significant positive association between the A allele of the SNP rs1447295 and prostate cancer risk [odds ratio, 1.4; 95% confidence interval (95% CI), 1.1-2.0] but no significant association with the microsatellite DG8S737. However, significant associations were observed for both markers in men with high Gleason scores. Adjusting for age, first-degree family history of prostate cancer, and prostate cancer screening history, the adjusted odds ratios were 1.4 (95% CI, 1.1-1.8) for the A allele of the SNP and 1.9 (95% CI, 1.2-2.8) for the −10 allele of the microsatellite. Conclusions: These data suggest that the locus on chromosome 8q24 harbors a genetic variant associated with prostate cancer and that the microsatellite marker is a stronger risk factor for aggressive prostate cancers defined by poorly differentiated tumor morphology. (Cancer Epidemiol Biomarkers Prev 2007;16(4):809–14)

Abstract Two variants (rs1447295/DG8S737) of chromosome 8q24 were recently reported to be associated with increased risk of prostate cancer (PC). To confirm this finding, we genotyped and compared the frequencies of these polymorphisms among 1,121 Caucasian men with PC (435 men with familial PC, 491 men with sporadic PC, and 195 men with aggressive PC) to 545 population-based controls. For the single nucleotide polymorphism marker rs1447295, frequencies of the minor allele (A) were 10.3% in controls, 11.9% in sporadic cases, 16.7% in familial cases, and 17.2% in aggressive cases. Compared with controls, the A allele was significantly more common in both familial PC [odds ratios (OR), 1.93; 95% confidence intervals (95% CI), 1.37–2.72; P = 0.0004] and aggressive PC (OR, 1.87; 95% CI, 1.28–2.74; P = 0.0005) but not for sporadic PC (OR, 1.16; 95% CI, 0.85–1.58; P = 0.25). Although the A allele was more frequent in aggressive PC cases when compared with controls, the allele frequencies were similar among cases with high- and low-grade PC (Gleason grades &lt;7 and ≥7, respectively). For the microsatellite marker DG8S737, the −8 allele was significantly more frequent in familial PC (OR, 1.68; 95% CI, 1.09–2.60; P = 0.031), whereas the −10 allele was more frequent in aggressive PC (OR, 2.85; 95% CI, 1.52–5.36; P = 0.0004). Haplotype analysis showed significant differences in haplotype frequencies between the familial PC (P = 0.006) and aggressive PC (P = 0.005) cases versus controls. The −8/A haplotype showed the strongest association with familial PC (P = 0.008), whereas the −10/A haplotype was most strongly associated with aggressive PC (P = 0.00005). These results further confirm the importance of these two polymorphic variants (rs1447295 and DG8S737) as risk factors for PC. However, the mechanism explaining this increased risk has not yet been established. [Cancer Res 2007;67(7):2944–50]

We compared the treatment-related mortality, relapse rate, disease-free survival (DFS), and overall survival (OS) by cytogenetic risk group of 261 patients with acute myeloid leukemia in first complete remission (CR1) and 299 patients in CR2 in undergoing matched unrelated donor hematopoietic stem cell transplantation (HSCT). For patients in first CR, the DFS and OS at 5 years were similar for the favorable, intermediate, and unfavorable risk groups at 29% (95% confidence interval [CI], 8%-56%) and 30% (22%-38%); 27% (19%-39%) and 29% (8%-56%); and 30% (95% CI, 22%-38%) and 30% (95% CI, 20%-41%), respectively. For patients in second CR, the DFS and OS at 5 years were 42% (95% CI, 33%-52%) and 35% (95% CI, 28%-43%); 38% (95% CI, 23%-54%) and 45% (95% CI, 35%-55%); and 37% (95% CI, 30%-45%) and 36% (95% CI, 21%-53%), respectively. Cytogenetics had little influence on the overall outcome for patients in first CR. In second CR, outcome was modestly, but not significantly, better for patients with favorable cytogenetics. The graft-versus-leukemia effect appeared effective, even in patients with unfavorable cytogenetics. However, treatment-related mortality was high. Matched unrelated donor HSCT should be considered for all patients with unfavorable cytogenetics who lack a suitable HLA-matched sibling donor.