The Use of FluorescenceIn SituHybridization (FISH) in Chronic Lymphocytic Leukemia (CLL)

Chemoimmunotherapy with oral low-dose fludarabine, cyclophosphamide and rituximab (old-FCR) as treatment for elderly patients with chronic lymphocytic leukaemia

Median age at diagnosis for chronic lymphocytic leukaemia (CLL) patients is now 72 years, thus a consistent number of patients may not tolerate standard doses i.v. of fludarabine, cyclophosphamide and rituximab (FCR), the best available therapy, due to unacceptable myelotoxicity and risk of severe infections. We studied safety and efficacy of the addition of rituximab to the oral low-dose FC regimen (old-FCR) in a selected population of 30 elderly (median age 75, 15 untreated, 15 treated with 1 prior therapy) CLL patients. Complete remission (CR) rate was 80% in the untreated patients (overall response rate, ORR 93%), and 30% in pretreated patients (ORR 74%). Progression free survivals (PFS) were 45 months and 30 months in the untreated and treated patients, respectively. In patients achieving CR, old-FCR led to PFS of 67 months. Moreover, haematological toxicity was mild (grade 3-4: 15%) and patients were treated mostly in outpatient clinic. Old-FCR could be a good therapy option for elderly CLL patients outside clinical trials, larger studies are needed to confirm our findings.

Chromosomal abnormalities detected by multicolor fluorescence in situ hybridization in fine-needle aspirates from patients with small lymphocytic lymphoma are useful for predicting survival

BACKGROUND

Fine-needle aspiration (FNA) of lymph nodes is commonly used to assess disease progression in patients with small lymphocytic lymphoma (SLL). Although cytologic features are helpful for diagnosing typical SLL and transformed large-cell lymphoma (tLCL), SLL in accelerated phase (SLLacc) is more difficult to diagnose. Additional tests are needed to identify those patients who are transforming to a higher-grade lymphoma. This study evaluated the use of a multicolor fluorescence in situ hybridization (FISH) probe panel specifically designed for chronic lymphocytic leukemia (CLL)/SLL and assessed the association between FISH findings and cytologic diagnosis, proliferation index, and risk of death.

METHODS

FNA specimens from 50 patients (32 men and 18 women; mean age, 57 years [range, 36-77 years]) with histologically confirmed CLL and/or SLL were evaluated in this study for chromosomal abnormalities of 11q22 (ATM), 12, 13q14.3, 13q34.3 (LAMP1), and 17p13.1 (p53) by using a multiprobe FISH kit. One of the 50 cases was excluded because of an insufficient number of cells for FISH analysis. The FISH findings were compared with the cytologic diagnoses (26 SLLs, 12 SLLaccs, and 11 tLCLs), Ki-67 immunostaining, and risk of death.

RESULTS

Abnormal signal patterns for 17p13.1 and 13q34.3 were associated with tLCL. Aberrations of 17p13.1 were found to be significantly associated with Ki-67 staining. Of the 49 patients with interpretable FISH results, 22 (45%) had died at the time of the study, with a mean overall survival time of 17 months after FNA. Patients with aberrations of 17p13.1 and 11q22 had 3.7 and 2.7 times the risk of death, respectively, compared with patients with normal patterns.

CONCLUSIONS

FISH can be performed on FNA specimens from patients with a history of SLL/CLL. Chromosomal aberrations of 17p13.1 and 11q22 are associated with an increased risk of death. Knowledge of genetic abnormalities from FNAs may be useful in deciding when and how to treat indolent or progressive SLL.

Diagnostic Molecular Pathology: An Increasingly Indispensable Tool for the Practicing Pathologist

Context.—Diagnostic molecular pathology is rapidly becoming an indispensable tool for anatomic pathologists. Familiarity with some of the technologic principles and current, as well as upcoming, molecular diagnostic applications is greatly advantageous for today's practice of pathology.

Objectives.— To provide a discussion of the most common techniques currently used in molecular pathology laboratories and review their essential applications to diagnosis and management of neoplastic diseases.

Data Sources.—A literature review and illustrative cases from the authors' molecular diagnostic practices.

Conclusions.—Applications such as clonality assays, molecular cytogenetics, and chimerism analysis are providing us with accurate tools to resolve difficult diagnostic and management decisions in hemato-oncology. This should serve as a future model to expand molecular applications into the wider field of solid tumors.

Superoxide generation by Nox1 in guinea pig gastric mucosal cells involves a component with p67(phox)-ability

Nox1, a homologue of gp91(phox) subunit of the phagocyte NADPH oxidase, is responsible for spontaneous superoxide (O(2)(-)) generation in guinea pig gastric mucosal cells (GMC), but involvement of regulatory components (p67(phox), p47(phox), and Rac) which are essential in phagocytes remains unknown. Here, we aimed to figure out how Nox1 of GMC achieves an active oxidase status. GMC in primary culture show low O(2)(-) generation but acquire a 9-fold higher activity when cultured with Helicobacter pylori lipopolysaccharide (LPS), in correlation with a far increased Nox1 expression. Investigation into the O(2)(-)-generating ability of LPS-induced Nox1 in cell-free reconstitution assays showed that: 1) Nox1 is unable to generate O(2)(-) per se; 2) the combination of Nox1 with GMC cytosol is insufficient for a significant O(2)(-) generation; 3) the combination with neutrophil cytosol enables Nox1 to act like gp91(phox), i.e., to produce O(2)(-) appreciably in response to myristate stimulation; 4) Nox1 prefers NADPH to NADH under the in vitro assay with neutrophil cytosol plus myristate (K(m)=10.4 microM); 5) substitution of neutrophil cytosol by a set of recombinant cytosolic components (rp67(phox), rp47(phox), Rac2) is, however, ineffective and still requires GMC cytosol. Thus, Nox1 probably requires an additional cytosolic factor(s). In contrast, GMC cytosol enables cytochrome b(558) to generate plenty of O(2)(-), on condition that rp47(phox) is added. This result suggests that GMC cytosol contains a component with p67(phox)-ability, and also Rac, but lacks p47(phox). These data indicate that GMC Nox1 requires at least a p67(phox) counterpart and Rac to acquire NADPH oxidase activity.