A cytostatic drug improves control of HIV-1 replication during structured treatment interruptions: a randomized study

OBJECTIVE: To study the effect of highly active antiretroviral therapy (HAART) with and without hydroxyurea (HU) on changes in plasma viral load (VL) set-point, and on HIV-1-specific responses, after five cycles of structured treatment interruptions (STI). METHODS: A group of 20 patients taking HAART for chronic HIV infection with VL < 20 copies/ml were randomized to continue HAART or HAART plus HU for 24 weeks followed by five STI cycles. HU was also stopped in cycles 1-3 but continued in cycles 4 and 5. The number of individuals maintaining a VL set-point < 5000 copies/ml during the fifth interruption were determined. RESULTS: VL remained < 5000 copies/ml in eight out of nine patients in the HU group and in four out of ten patients in the HAART group after a median 48 weeks of follow-up after the fifth interruption ( P=0.039). By STI cycle 5, there was a significant increase in the neutralizing activity (NA), in both magnitude and breadth of the total cytotoxic T lymphocyte (CTL) response and in lymphoproliferative response (LPR) from baseline. No significant differences were observed between HAART and HU groups in NA, CTL and LPR at any time-point. There were no differences in the NA titers at any time-point between responder and non-responder patients. There was a trend for higher CTL and LPR levels in responder patients (P= 0.10). CONCLUSIONS: In this randomized, controlled study of STI with cycles of HAART or HAART plus HU, a lower peak VL rebound and a lower VL set-point was achieved in patients continuing HU while other drugs were discontinued. HU did not blunt anti-HIV-1-specific responses; however, control of VL did not correlate with anti-HIV-1-specific cellular immune responses.     

Lamivudine prophylaxis prevents hepatitis B virus reactivation in anti-HBc positive patients under rituximab for non-Hodgkin lymphoma

Backgound

A significant proportion of hepatitis B surface antigen (HBsAg) negative/anti-hepatitis B core antigen (anti-HBc) positive patients with non-Hodgkin lymphoma (NHL) undergoing rituximab-based chemotherapy (R-CT) may suffer hepatitis B virus (HBV) reactivation.

Autologous tandem transplantation in patients with primary progressive or relapsed/refractory lymphoma

Patients with primary progressive or refractory Hodgkins disease (HD) or aggressive non-Hodgkins lymphoma (NHL) have a particularly poor prognosis. Here we report the results of autologous tandem transplantation in these patients. Patients aged 18–55 years with primary progressive or refractory relapsed HD and aggressive NHL were included. Patients received high-dose etoposide (2000 mg/m²) followed by peripheral blood stem cell harvest (PBSC). The first high-dose chemotherapy (TMC) consisted of thiotepa (750 mg/m²), mitoxantrone (40 mg/m²), and carboplatin (990 mg/m²). Patients with no change (NC), partial remission (PR), or complete remission (CR) after TMC then received BEAM with carmustine (300 mg/m²), etoposide (1200 mg/m²), cytarabine (1600 mg/m²), and melphalan (140 mg/m²). Patients with bulky disease (>5 cm) or residual lymphoma received involved field radiotherapy. Twenty-five patients were included (HD=10, NHL=15, median age 34 years). Two patients with HD achieved a CR and five patients a PR [response rate (RR) 70%]. Three patients (30%) experienced treatment failure including two deaths due to peritransplant complications. Five patients with aggressive NHL were in CR and two patients in PR (RR 46%). Of the eight patients (56%) with treatment failure, three had progressive disease and five died from peritransplant complications. Freedom from treatment failure (FFTF) and overall survival (OS) for all patients after 12 months was 28% and 40%, respectively. Tandem HDCT followed by autologous stem cell transplantation (ASCT) offers a chance of cure in these poor prognostic patients, but is associated with risks.J.-P. Glossmann and J. O. Staak have contributed equally to this work.     

Chk2 drives late G1/early S phase arrest of clonal myeloid progenitors expressing the p210 BCR-ABL tyrosine kinase in response to STI571

STI571 is the most innovative drug for the cure of Chronic Myeloid Leukemia. It inhibits, in fact, the disease causative event, the p210 bcr-abl tyrosine kinase, and addresses clonal myeloid progenitors to apoptotic death. Here, we demonstrated that STI571 also induces growth arrest by activating the Chk2-Cdc25A-Cdk2 axis, a pathway complementary to p53 in the activation of G(1)/S cell cycle checkpoint. In vitro exposure to STI571 of 32D murine myeloid progenitor cell clones transducing a temperature-sensitive p210 bcr-abl construct was associated with Chk2 phosphorylation and activation, Cdc25A degradation and persistent Cdk2 inhibitory phosphorylation, preventing, in turn, cell transition to and progression throughout the S phase of cell cycle. Chk2 and Cdc25A are both components of a complex network that integrates signals involved in regulated cell cycle progression, DNA repair and cell decision between life or death. Chk2 gene mutations or decreased expression, leading to its protein loss of function on Cdc25A target, and Cdc25A overexpression have been linked to poor prognosis of human cancers. In CML, they might further enhance the proliferative advantage and genomic instability of clonal myeloid progenitors featuring a class of poor prognosis patients eventually resistant to STI571.     

Gadolinium magnetic angioresonance in the study of aortoiliac disease

There is a need for noninvasive methods for the early identification of patients with intermittent claudication who need surgical treatment. Newer magnetic resonance angiography (MRA) techniques allow detailed study of the arterial tree with image quality similar to that of conventional arteriography. From April 1997 to January 2001, 30 patients with intermittent claudication of the lower limbs were studied with both imaging methods. In each case, the MRA images were examined first and the arteriographic images were examined 15 days later. Examiners interpreting the arteriographic images were blinded to the results of the corresponding MRA images. After each examination (MRA and arteriography), a vascular surgeon suggested a surgical plan. MRA showed results similar to those of arteriography, although with inferior image quality. No patient had an allergic reaction or side effects due to administration of contrast material. There was total agreement between MRA and arteriography in regard to the morphologic analysis and proposed surgical plans in every case. In conclusion, MRA is a feasible, useful, and less invasive alternative for the morphologic evaluation of the aortofemoral area in patients with intermittent claudication of lower limbs.     

Accumulation of catalytically active PKC-ζ into the nucleus of HL-60 cell line plays a key role in the induction of granulocytic differentiation mediated by all-trans retinoic acid

The effect of differentiating doses of all- trans retinoic acid (ATRA, 10⁻⁶  m ) and vitamin D3 (10⁻⁷  m ) was investigated on the nuclear levels of endogenous ceramide and protein kinase C-ζ (PKC-ζ) catalytic activity in HL-60 myeloid cells. ATRA induced a parallel increase of ceramide and catalytically active PKC-ζ into the nuclear compartment of HL-60 cells (peak at 72 h). On the other hand, vitamin D3 increased the levels of nuclear ceramide and PKC-ζ activity to a lesser extent and with a delayed kinetics compared to ATRA (peak at 96 h).
Pretreatment of HL-60 cells with high pharmacological concentrations of exogenously-added C₂-ceramide (10⁻⁶  m ) completely blocked the ATRA-mediated activation of nuclear PKC-ζ. Exogenous C₂-ceramide (10⁻⁶  m ) also inhibited the granulocytic differentiation induced by ATRA, whereas it did not affect monocytic differentiation mediated by vitamin D3.
Transient transfection experiments performed with a plasmid construct containing a constitutively active mutated form of the PKC-ζ cDNA fused in 3' to a fluorescent tag protein (pEGFP-PKC-ζ) demonstrated that the overexpression of catalytically active PKC-ζ was not accompanied by the appearance of a differentiated morphology. These findings suggest that nuclear PKC-ζ is necessary but not sufficient to induce granulocytic differentiation of HL-60 myeloid malignant cells.     

Neuroadrenergic denervation of the lung in type I diabetes mellitus complicated by autonomic neuropathy

STUDY OBJECTIVE: To verify whether autonomic neuropathy (AN) complicating type I, insulin-dependent diabetes mellitus affected neuroadrenergic bronchopulmonary innervation. PATIENTS: Twenty nonsmoking diabetic patients without respiratory diseases were studied: 11 patients with AN (group AN) and 9 patients without AN (control; group C) diagnosed by standardized criteria. DESIGN: Patients underwent respiratory function tests and ventilatory scintigraphies with (123)I-metaiodobenzylguanidine (MIBG) and with (99m)Tc-diethylenetriaminepenta-acetic acid (DTPA) to assess both bronchopulmonary neuroadrenergic innervation and also permeability of the alveolar-capillary barrier to water-soluble tracers. Rates of pulmonary clearance of the two tracers were computed, and correlates were identified by nonparametric statistics. SETTING: University hospital. RESULTS: The AN and C groups had normal respiratory function test results and comparable duration of diabetes and quality of metabolic control. (99m)Tc-DTPA clearance did not distinguish the groups. (123)I-MIBG clearance was faster in the AN group than in the C group (mean +/- SD half-time of the radiotracer time-activity curve [T(1/2)], 116.1 +/- 22.8 min in the AN group vs 139.5 +/- 18.3 min in the C group, p = 0.022), which is consistent with neuroadrenergic denervation in the AN group. (123)I-MIBG clearance was independent from (99m)Tc-DTPA clearance. Faster (123)I-MIBG clearance was significantly associated with worse performance in three of the four autonomic tests. CONCLUSIONS: Neuroadrenergic bronchopulmonary denervation may occur in diabetic patients with AN despite normal clinical and respiratory function findings. Further research is needed to identify clinical and prognostic implications of these findings.