Distinct gene expression profiles of proximal and distal colorectal cancer: implications for cytotoxic and targeted therapy.

Colorectal cancer (CRC) is a heterogeneous disease with genetic profiles and clinical outcomes dependent on the anatomic location of the primary tumor. How location has an impact on the molecular makeup of a tumor and how prognostic and predictive biomarkers differ between proximal versus distal colon cancers is not well established. We investigated the associations between tumor location, KRAS and BRAF mutation status, and the messenger RNA (mRNA) expression of proteins involved in major signaling pathways, including tumor growth (epidermal growth factor receptor (EGFR)), angiogenesis (vascular endothelial growth factor receptor 2 (VEGFR2)), DNA repair (excision repair cross complement group 1 (ERCC1)) and fluoropyrimidine metabolism (thymidylate synthase (TS)). Formalin-fixed paraffin-embedded tumor specimens from 431 advanced CRC patients were analyzed. The presence of seven different KRAS base substitutions and the BRAF V600E mutation was determined. ERCC1, TS, EGFR and VEGFR2 mRNA expression levels were detected by reverse transcriptase-PCR. BRAF mutations were significantly more common in the proximal colon (P<0.001), whereas KRAS mutations occurred at similar frequencies throughout the colorectum. Rectal cancers had significantly higher ERCC1 and VEGFR2 mRNA levels compared with distal and proximal colon tumors (P=0.001), and increased TS levels compared with distal colon cancers (P=0.02). Mutant KRAS status was associated with lower ERCC1, TS, EGFR and VEGFR2 gene expression in multivariate analysis. In a subgroup analysis, this association remained significant for all genes in the proximal colon and for VEGFR2 expression in rectal cancers. The mRNA expression patterns of predictive and prognostic biomarkers, as well as associations with KRAS and BRAF mutation status depend on primary tumor location. Prospective studies are warranted to confirm these findings and determine the underlying mechanisms.

KRAS mutations in non-small-cell lung cancer and colorectal cancer: implications for EGFR-targeted therapies.

BACKGROUND: KRAS mutations are associated with diverse biologic functions as well as prognostic and predictive impact in non-small cell-lung cancer (NSCLC) and colorectal cancer (CRC). In CRC, benefit from monoclonal antibody therapies targeting EGFR is generally limited to patients whose tumors have wild-type (WT) KRAS, whereas data suggest that this association is not present for NSCLC. We hypothesized that the unique tobacco-related carcinogenesis of NSCLC results in a divergence of KRAS MT genotype compared with CRC, contributing to differences in outcomes from EGFR-targeted therapies. MATERIAL AND METHODS: Tumor from 2603 patients (838 CRC and 1765 NSCLC) was analyzed for KRAS mutations. DNA was extracted from microdissected formalin-fixed-paraffin-embedded specimens (FFPE) and 7 different base substitutions in codons 12 and 13 of KRAS were determined. RESULTS: KRAS mutation genotype differed significantly between NSCLC and CRC in frequency (25% vs. 39%; p<0.001), smoking-associated G>T transversions (73% versus 27%; p<0.001), and ratio of transversions to transitions (3.5 vs. 0.79; p<0.001). In NSCLC GLY12Cys mutations, resulting from a codon 12 GGT>TGT substitution, were observed in 44% compared to 10% for CRC. In contrast, codon 12 or 13 GLY>ASP substitutions (resulting in a G>A transition) were more frequent in CRC (42%) compared with NSCLC (21%). CONCLUSION: In this large dataset, KRAS mutation patterns are quantitatively and qualitatively distinct between NSCLC and CRC, reflecting in part differences in tobacco-related carcinogenesis. In light of differences in predictive value for EGFR-directed monoclonal antibody therapy and prognosis for specific KRAS mutations between NSCLC and CRC, these data provide an underlying biologic rationale.

Cisplatin-induced nonimmunologic adsorption of immunoglobulin by red cells.

Antibodies to cisplatin, an extensively used anticancer chemotherapeutic agent, have been implicated previously as a cause of immune hemolytic anemia. Investigation of a suspected case of cisplatin-induced hemolytic anemia in a 40-year-old man demonstrated that IgG could be adsorbed nonimmunologically by reagent red cells in vitro. This phenomenon was found to be a source of possible error in the interpretation of studies identifying specific cisplatin antibodies. Furthermore, cisplatin was found to be capable of producing a positive direct antiglobulin test (DAT), owing to the nonspecific adsorption of immunoglobulin and complement in vivo. Although this finding did not result in acute hemolysis, it may cause confusion in the investigation of DAT-positive hemolytic anemias. We question whether previous reports of cisplatin-induced hemolytic anemia are accurate in their assessment that such hemolysis was mediated immunologically. Future studies of suspected cases of hemolysis induced by this drug should include serologic investigation adequate to demonstrate the presence of specific cisplatin antibodies. A positive DAT in such patients should not be considered proof of drug-induced immune hemolytic anemia.

Single donor platelets: can we afford to use them? Can we afford not to use them?

One of the strategies to reduce the risk of harming a patient by transfusion therapy is to limit the overall risk of transfusion-transmitted disease. Central to this approach is minimizing the number of allogeneic blood products with which a patient is transfused. The usual dose of platelets for an adult patient is either six to 10 random donor platelets vs. one unit of platelets, pheresis (so-called single donor apheresis platelets). Consequently, the transfusion services at the University of Southern California Health Sciences Campus (USC University Hospital, the Norris Cancer Hospital, and Los Angeles County + USC Medical Center) routinely use single donor apheresis platelets (SDPs) rather than random donor platelets (RDPs) in an effort to minimize allogeneic platelet transfusions, and thereby reduce risk of transfusion-transmitted infection. Although there are other compelling medical, technical, and medical-legal reasons to use SDPs instead of RDPs, the authors believe that a decrease in allogeneic donor exposures alone is sufficient reason to make SDPs the platelet component of choice at their institutions.

Safety of blood donations following a natural disaster.

To evaluate the relative safety of blood donations given in response to a major disaster, donor demographics and infectious disease test results were compared for donations made during the 10 days following the October 17, 1989, San Francisco Bay Area earthquake and those made during the preceding 6 months. These comparisons were made for donations given to the regional blood center in the area that was immediately affected by the disaster (Irwin Memorial Blood Centers) and for those given in an unaffected region (Los Angeles/Orange Counties Region, American Red Cross Blood Services). The rate of donation increased more than 200 percent during the 5 days following the earthquake in both the disaster-affected and unaffected regions. Both the disaster-affected and unaffected regions observed significant increases in the proportions of donations by first-time donors, by persons aged 20 to 39 years, and by women. The rates of confirmed positivity for infectious disease markers for post-earthquake donations did not differ significantly from rates for homologous donations given during the preceding 6 months, particularly when the rates were adjusted for the increased representation of first-time donors. Approximately 39 percent of post-earthquake first-time donors gave blood again within the following 6-month period. It is concluded that donations given after major disasters are essentially as safe as routine donations and that active efforts to recruit these donors again can be undertaken without reservation.

[Measurement of gravity line position 15-25 years after Harrington-spondylodesis in adolescent idiopathic scoliosis]. / Untersuchungen zum Schwerpunktlot 15-25 Jahre nach Harrington-Distraktionsspondylodese bei Patienten mit idiopathischer Adoleszentenskoliose.

AIM: A prospective analysis was performed to evaluate the relation between sagittal spinal morphology, gravity line position and morphological parameters of the pelvis and lumbar spine. METHOD: 25 patients with a mean follow-up of 23 (15-37) years after thoracic Harrington distraction spondylodesis were included. Standing lateral full spine radiographs were performed while patients were standing on a force plate. Pelvic angles according to Duval-Beaupere were measured. RESULTS: Pelvic incidence varied from 30 degrees to 76 degrees (mean 52.1 degrees + 12.5 degrees ). Mean sacral slope was 36.4 degrees (+ 7.8 degrees ). The average thoracic kyphosis (23.6 degrees + 14.3 degrees ) and lumbar lordosis (36.4 degrees + 9.2 degrees ) were diminished. The gravity line position was on average 10.9 mm (+ 21.6mm) posterior to the center of the femoral heads. CONCLUSION: Our method quantifies the relationship between the gravity line position and pelvic parameters according to Duval-Beaupere. The homogenous study group of patients with AIS after Harrington spondylodesis is characterized by decreased lumbar and thoracic profile and posterior displacement of the gravity line position.

An acute hemolytic transfusion reaction caused by an anti-P1 that reacted at 37 degrees C.

BACKGROUND: Hemolytic transfusion reactions (HTRs) due to anti-P1 have rarely been reported. There is only one report (from 1945) of an acute HTR due to anti-P1. CASE REPORT: A 74-year-old woman with anti-P1 was given blood that had been found to be compatible by the use of prewarmed serum and saline-suspended red cells (RBCs) and of an antiglobulin test with anti-IgG. The test mixtures were not centrifuged or inspected for agglutination after the 37 degrees C incubation phase. After transfusion of 50 mL of P1 + blood, the patient had an acute HTR (hemoglobinemia, hemoglobinuria, and increased blood pressure, temperature, and respiration). RESULTS: When studied by a reference laboratory, the anti-P1 was shown to be easily detectable (3+ agglutination) by a prewarming technique (saline or low-ionic-strength saline [LISS]), which included centrifugation at 37 degrees C, but only weak reactions were observed when centrifugation after 37 degrees C incubation was omitted. The indirect antiglobulin test was weakly positive (1+) with anti-IgG, but polyspecific anti-human globulin reacted 2+. The anti-P1 agglutinin was IgM, and its titer was 16 at 37 degrees C (prewarmed) and 256 at 23 degrees C; it caused hemolysis of RBCs at 37 degrees C under conditions known to enhance hemolysis. An indirect monocyte monolayer assay gave results of 11.2 and 22 percent in testing of P1 + RBCs incubated with the patient's serum alone and with patient's serum plus fresh normal serum (as a source of complement), respectively (normal < or = 3%). CONCLUSION: An acute HTR was caused by a hemolytic anti-P1 that reacted at 37 degrees C. This antibody was not detected by the hospital in a prewarmed crossmatch that omitted 1) the addition of LISS, 2) the reading for agglutination after the 37 degrees C incubation, and 3) the use of antiglobulin sera containing anti-complement.

Human immunodeficiency virus infection among health care workers who donate blood.

OBJECTIVE: To estimate the prevalence of human immunodeficiency virus (HIV) infection among health care workers who donate blood. DESIGN: Point prevalence survey of blood donors. SETTING: 20 U.S. blood centers that participate in an ongoing interview study of HIV-seropositive blood donors. MEASUREMENTS: Prevalence rates for HIV in persons who reported being health care workers were measured directly for 6 of the 20 blood centers. For the other 14 centers, we derived the numerator from the interview study in the same manner used for the 6 centers; we estimated the denominator using blood collection logs at those centers and extrapolations from the survey completed at the 6 blood centers. RESULTS: Between March 1990 and August 1991, 8519 health care workers donated blood at 6 hospitals and other medical facilities. Three persons were HIV seropositive: Two reported being health care workers and having nonoccupational risk factors for HIV infection; the occupation and other possible risk factors of the third seropositive donor could not be determined. Therefore, the highest overall prevalence of HIV infection among health care worker donors at these 6 centers was 0.04% (3 of 8519; upper limit of 95% CI, 0.1%). We estimated that during the same period, approximately 36,329 health care workers were tested for HIV at all 20 centers. Twenty-seven persons infected with HIV who donated at hospitals were identified; 7 did not return for interviews, so their health care occupations could not be verified. Thus, the highest estimated overall prevalence of HIV infection among health care worker donors at the 20 centers was 0.07% (27 of 36,329; upper limit of CI, 0.1%). Of the 20 known health care worker donors, 11 reported nonoccupational risks for HIV infection; 3 of the remaining 9 health care workers described occupational blood exposures that could have resulted in transmission of HIV. CONCLUSIONS: Blood donors can serve as a sentinel cohort when evaluating the risk for occupationally acquired HIV infection. These findings suggest that among the many health care worker donors in this study, HIV infection attributable to occupational exposure was uncommon.