Impact of granulocyte colony-stimulating factors in metastatic colorectal cancer patients

BACKGROUND

Delays in chemotherapy because of neutropenia may be associated with poorer outcomes. The purpose of the present study was to examine the effect that granulocyte colony-stimulating factors (g-csfs) have on survival.

METHODS

We conducted a chart review of all outpatients diagnosed with metastatic colorectal cancer and treated with folfiri chemotherapy (irinotecan, 5-fluorouracil, leucovorin) with or without bevacizumab at Mount Sinai Hospital between 2007 and 2012. Multivariable Cox proportional hazards models were used to compare survival in neutropenic patients treated with g-csf, in neutropenic patients not so treated, and in patients without neutropenia.

RESULTS

The review identified 93 patients, 31 of whom did not experience a neutropenic event. Of the 62 who experienced neutropenia, 18 were managed with g-csf support, and 44, with reductions or delays in dose. Compared with patients experiencing a neutropenic episode not treated with g-csf, those treated with g-csf experienced a nonsignificant increase in time to event [progression or death: hazard ratio (hr): 1.37; 95% confidence limits (cl): 0.72, 2.61], but compared with patients not having a neutropenic episode, the same patients experienced a significant increase in time to event (hr: 2.07; 95% cl: 1.03, 4.15).

CONCLUSIONS

In patients who experienced neutropenia, g-csf did not have a statistically significant impact on survival. Time to event was prolonged in g-csf-treated patients compared with patients who did not experience neutropenia.

Combined hyperlipidemia/hyperalphalipoproteinemia associated with premature spontaneous atherosclerosis in mice lacking hepatic lipase and low density lipoprotein receptor

BACKGROUND AND METHODS

Hepatic lipase (HL) is an enzyme which hydrolyzes triglycerides from plasma lipoproteins and thus takes part in the metabolism of triglyceride-rich lipoprotein remnants and high density lipoproteins. The search described here concentrated on the description of the double invalidation of the HL and LDL receptor genes in mice in order to better understand the possible role of HL in combined hyperlipidemia/hyperalphalipoproteinemia and development of atherosclerosis.

RESULTS

We show here that mice lacking both endogenous HL and LDL receptor (HL-/-:LDLR-/-) dramatically increased their plasma triglyceride-rich lipoproteins and their remnants as a consequence of reduced liver uptake. This result is strenghthened by the fact that HL-/-:LDLR-/- were found to overexpress LRP, LSR, and apoE genes. Interestingly, HL-/-:LDLR-/- mice showed premature spontaneous atherosclerosis and aortic lesions from 1-year-old animals were two-fold larger than those of LDLR-/- single mutants. We confirmed that HL-/- and wild-type mice did not develop atherosclerosis lesion even 1 year after birth.

CONCLUSIONS

Analysis of this double HL-LDLR knockout mouse model provides in vivo evidence that HL has a major role in the clearance of TRL remnants when LDLR is deficient and in the reduction of the development of atherosclerosis.

Further analysis of VNTR and MIRU in the genome of Mycobacterium avium complex, and application to molecular epidemiology of isolates from South America

All members of Mycobacterium avium complex are serious pathogens for humans and animals. The aim of this study was to look for and analyze VNTR-MIRU loci in the genome of M. avium complex and their preliminary application to test these isolates. In the present study, we identified 22 novel VNTR-MIRU by using Tandem Repeat software: five with a structure similar to MIRU and 17 without MIRU structure; these latter were designated as VNTR. Most VNTR were located within predicted coding regions. Most MIRU were intercistronic with their extremities overlapping the termination and initiation codons of their flanking genes. Some of these VNTR-MIRU exhibited polymorphism among M. avium complex isolates due to insertion or deletion of whole repeats and/or of nucleotide sequence degeneration. We determined the variability of six VNTR-MIRU loci in 21 M. avium subsp. hominissuis and 26 M. avium subsp. paratuberculosis. The analysis identified 15 different alleles with the combination of six VNTR-MIRU in the 21 M. avium subsp. hominissuis with 16 different IS1245 RFLP and four different profiles with PCR-restriction analysis of hsp65 (PRA). However, neither the six VNTR-MIRU loci nor the PRA were able to distinguish M. avium subsp. paratuberculosis isolates with five different IS900 RFLP profiles. In conclusion, some of the VNTR-MIRU loci identified were useful to differentiate M. avium subsp. hominissuis but not M. avium subsp. paratuberculosis isolates here included. However, we observed polymorphism in VNTR-MIRU loci between M. avium subsp. hominissuis and M. avium subsp. paratuberculosis genomes, which could be important in the understanding of the obvious differences in the pathogenic effects of these mycobacteria.