Hairy cell leukaemia: review of treatment

Interferon-β lipofection I. Increased efficacy of chemotherapeutic drugs on human tumor cells derived monolayers and spheroids

We evaluated the effect of hIFNβ gene transfer alone or in combination with different antineoplastic drugs commonly used in cancer treatment. Five human tumor-derived cell lines were cultured as monolayers and spheroids. Four cell lines (Ewing sarcomas EW7 and COH, melanoma M8 and mammary carcinoma MCF-7) were sensitive to hIFNβ gene lipofection. Although this effect appeared in both culture configurations, spheroids showed a relative multicellular resistance (insensitive colon carcinoma HT-29 excluded). EW7 and M8 hIFNβ-expressing cells were exposed to different concentrations of bleomycin, bortezomib, carboplatin, doxorubicin, etoposide, methotrexate, paclitaxel and vincristine in both configuration models. In chemotherapy-sensitive EW7 monolayers, the combination of hIFNβ gene and antineoplastic drugs displayed only additive or counteractive (methotrexate) effects, suggesting that cytotoxic mechanisms triggered by hIFNβ gene lipofection could be saturating the signaling pathways. Conversely, in chemotherapy-resistant EW7 spheroids or M8 cells, the combination of hIFNβ with drugs that mainly operate at the genotoxic level (doxorubicin, methotrexate and paclitaxel) presented only additive effects. However, drugs that also increase pro-oxidant species can complement the antitumor efficacy of the hIFNβ gene and clearly caused potentiated effects (bleomycin, bortezomib, carboplatin, etoposide and vincristine). The great bystander effect induced by hIFNβ gene lipofection could be among the main causes of its effectiveness, because only 1 or 2% of EW7 or M8 hIFNβ-expressing cells killed more than 60 or 80% of cell population, respectively.

Ultimate fate of oncology drugs approved by the us food and drug administration without a randomized Trial

PURPOSE

To approve a new anticancer drug, the US Food and Drug Administration often requires randomized trials. However, several oncology drugs have been approved on the basis of objective end points without a randomized trial. We reviewed the long-term safety and efficacy of such agents.

METHODS

We searched the Web site of the US Food and Drug Administration's Center for Drug Evaluation and Research and MEDLINE for initial applications of investigational anticancer drugs from 1973 through 2006.

RESULTS

Overall, 68 oncology drugs, excluding hormone therapy and supportive care, were approved, including 31 without a randomized trial. For these 31 drugs, a median of two clinical trials (range, one to seven) and 79 patients (range, 40 to 413) were used per approval. Objective response was the most common end point used for approval; median response rate was 33% (range, 11% to 90%). Thirty drugs are still fully approved. United States marketing authorization for one drug, gefitinib (an epidermal growth factor receptor [EGFR] inhibitor), was rescinded after a randomized trial showed no survival improvement; however, this trial was performed in unselected patients, and it was subsequently demonstrated that patients with EGFR mutation are more likely to respond. Nineteen of the 31 drugs have additional uses (per National Comprehensive Cancer Network or National Cancer Institute Physician Data Query guidelines), and subsequent formal US Food and Drug Administration approvals were obtained for 11 of these (range, one to 18 new indications). No drug has demonstrated safety concerns.

CONCLUSION

Nonrandomized clinical trials with definitive end points can yield US Food and Drug Administration approvals, and these drugs have a reassuring record of long-term safety and efficacy.

Interferons at age 50: past, current and future impact on biomedicine

The family of interferon (IFN) proteins has now more than reached the potential envisioned by early discovering virologists: IFNs are not only antivirals with a spectrum of clinical effectiveness against both RNA and DNA viruses, but are also the prototypic biological response modifiers for oncology, and show effectiveness in suppressing manifestations of multiple sclerosis. Studies of IFNs have resulted in fundamental insights into cellular signalling mechanisms, gene transcription and innate and acquired immunity. Further elucidation of the multitude of IFN-induced genes, as well as drug development strategies targeting IFN production via the activation of the Toll-like receptors (TLRs), will almost certainly lead to newer and more efficacious therapeutics. Our goal is to offer a molecular and clinical perspective that will enable IFNs or their TLR agonist inducers to reach their full clinical potential.

Strong inhibition of Ewing tumor xenograft growth by combination of human interferon-alpha or interferon-beta with ifosfamide

Ewing sarcoma is the second most common bone tumor in childhood. Despite aggressive chemotherapy and radiotherapy strategies, the prognosis of patients with metastatic disease remains poor. We have recently reported that Ewing tumor cell proliferation was strongly inhibited by IFN-beta and to a lesser degree by IFN-alpha. Moreover, under IFN-beta treatment, some cell lines undergo apoptosis. Since the possibility of using IFNs for Ewing tumor treatments may be of interest, we have evaluated the efficacy of Hu-IFNs in a nude mice model of Ewing tumor xenografts. The results reported here show that human type I IFNs, Hu-IFN-alpha and Hu-IFN-beta impaired tumor xenograft take and displayed an anti-growth effect toward established xenografts. Furthermore, we have also shown that combined therapy with Hu-IFNs and ifosfamide (IFO), an alkylating agent widely used in high-dose chemotherapy of Ewing tumors, results in a strong antitumor effect. Pathological analysis showed that Hu-IFN-alpha/IFO and Hu-IFN-beta/IFO were characterized by a dramatic decrease in the mitotic index and marked necrosis, as well as extensive fibrosis associated with numerous calcifications. To our knowledge, this is the first demonstration of a potential antitumor effect of human type I IFNs and IFO on Ewing tumors, providing a rational foundation for a promising therapeutic approach to Ewing sarcoma.

Cytotoxicity of 2-chlorodeoxyadenosine and arabinosylcytosine in leukaemic lymphoblasts from paediatric patients: significance of cellular nucleoside transporter content

2-chlorodeoxyadenosine (2-CdA) and arabinosylcytosine (araC) are nucleoside drugs that are used to treat various leukaemias, although 2-CdA has not been tested extensively in children with acute lymphoblastic leukaemia (ALL). Nucleoside cytotoxicity depends on the conversion of these agents to 5'-phosphate derivatives, following drug entry into cells via nucleoside transport (NT) processes. This study compared es nucleoside transporter content, determined using a flow cytometric assay with SAENTA [5'-S-(2-aminoethyl)-N6-(4-nitrobenzyl)-5'-thioadenosine] fluorescein, and cytotoxicities of 2-CdA and araC in fresh lymphoblasts from previously untreated paediatric ALL patients and the human T-lymphoblast cell line, CCRF-CEM. Lymphoblast samples from individual patients ranged widely in sensitivity to both 2-CdA (IC50, 6 nmol/l to > 5 micromol/l; mean = 418 nmol/l; n = 8) and araC (IC50, 59 nmol/l to > 5 micromol/l; mean = 1050 nmol/l; n = 7), although IC50 values for the two drugs were correlated (r = 0.78, P = 0.032, n = 7). Cellular es nucleoside transporter content varied more than 35-fold among samples from 10 patients. The correlation between es nucleoside transporter content and drug sensitivity was statistically significant for araC (r = -0.93, P = 0.023, n = 5), but not for 2-CdA (r = -0.57, P = 0.23, n = 6). Exposure of CCRF-CEM cells to araC resulted in a substantial araC concentration-dependent increase in the relative survival of es transporter-deficient cells, whereas the increase was slight following exposure to 2-CdA. We conclude that, in ALL lymphoblasts, es nucleoside transporter content is a determinant of araC sensitivity and that a deficiency in NT may impart resistance to araC.

Multiple myeloma and hairy cell leukemia: a rare association or coincidence?

Hairy cell leukemia (HCL) and multiple myeloma (MM) are well-defined entities with distinctive clinical and pathological features. Although most cases of HCL and MM fit their classic descriptions, more recent studies have revealed that their clinical and morphological boundaries may not only overlap but a transformation of HCL into MM could also occur. We report another case of HCL followed by the development of MM after 9 years. He also developed hemarthrosis of his right ankle at the time of diagnosis of MM. PCR analysis of DNA extracted from the bone marrow aspirate was negative for the presence of a monoclonally rearranged immunoglobulin heavy chain gene. Immunophenoytping revealed no evidence of HCL. There are several possible explanations for the development of MM in HCL patients, such as the coexistence of separate disease entities or different clinical and morphologic phases of a single disease entity. An accurate diagnosis of HCL or MM is critical because of differences in their treatment. Hemarthrosis in this patient may also have been the first manifestation of MM, a feature of MM which has rarely been reported.

Development of essential thrombocythemia in a patient treated with interferon alfa and pentostatin for hairy cell leukemia

A patient is reported who developed essential thrombocythemia after successful treatment for hairy cell leukemia. He was initially treated with interferon alfa and subsequently relapsed within one year of treatment. His diagnosis was reconfirmed and then treated with Pentostatin. Six years after treatment he had a progressive increase in the platelet count and was diagnosed as essential thrombocythemia. Second cancers including various types of hematological malignancy have been reported in patients with hairy cell leukemia treated with chemotherapy or interferon alfa. These malignancies may represent either a new clonal disorder or a complication of drug treatment. This is the first report of a chronic myeloproliferative disorder following successful treatment of hairy cell leukemia.

Ocular manifestation of hairy cell leukemia with dramatic response to 2-chloro-deoxy-adenosine

PURPOSE

To demonstrate that hairy cell leukemia may involve the eye.

METHODS

We examined a patient who had a unique ocular manifestation of hairy cell leukemia with severe panuveitis in one eye and leukemic retinopathy in the fellow eye.

RESULTS

Therapy with 2-chloro-deoxy-adenosine, a drug recently introduced for treatment of hairy cell leukemia, led to dramatic improvement of the ocular complications.

CONCLUSIONS

Hairy cell leukemia may involve the eye and ocular symptoms may respond to systemic treatment with 2-chloro-deoxy-adenosine.

Soluble interleukin-2 receptor in hairy-cell leukemia: a reliable marker of disease

The CD25 molecule, which corresponds to the p55 alpha chain of the interleukin-2 receptor, is strongly expressed by neoplastic cells in hairy-cell leukemia and is released in large amounts in the soluble form which is detectable in serum. In order to assess the reliability of the soluble interleukin-2 receptor as a disease marker in the management of patients with hairy-cell leukemia, we investigated serum levels in 35 untreated patients and in 2 patients with the hairy-cell leukemia variant. In 21 of 35 patients soluble receptor levels were also monitored during and after recombinant interferon-alpha therapy. Clinical and hematological parameters were also assessed. Soluble interleukin-2 receptor levels were extremely high at the time of diagnosis in patients with typical hairy-cell leukemia [32,722 +/- 27,001 vs. 331 +/- 145 units/ml in controls (mean +/- SD)], but not in patients with the leukemia variant. A progressive decrease in soluble interleukin-2 receptor levels paralleled the clinical response to treatment, although normal values were never detected, even in patients who achieved an apparent complete remission. After recombinant interferon-alpha discontinuation, disease recurrence was accompanied by a progressive increase to pre-treatment soluble receptor levels. Overall, a close correlation was found between soluble interleukin-2 receptor values and total tumor burden (r = 0.84, P < 0.001). On the basis of these data, soluble interleukin-2 receptor should be regarded as a key marker in the management of patients with hairy-cell leukemia.

Human natural interferon-alpha producing cells

Interferons (IFNs) are critical components of the host immune system, serving as antiviral agents, immunomodulators and inhibitors of cell growth. Among peripheral blood mononuclear cells, the primary IFN-alpha-producing cell is a light density, HLA-DR+ cell negative for cell surface markers typical for T cells, B cells, monocytes, natural-killer or progenitor cells and has been tentatively termed the 'natural IFN-producing cell' or NIPC. Although present in very low frequency (approximately 1:1000 among peripheral blood mononuclear cells), the NIPC are very potent, with an individual cell able to produce 1-2 IU of IFN. In this review, the characteristics, phenotype, regulation and relationship of NIPC to human disease are discussed.

Splenectomy in lymphoproliferative disorders: a report on 70 cases and review of the literature

Between February, 1970 and September, 1991, we performed splenectomies on 70 patients with chronic lymphoproliferative disorders including primary leukemias: 19 B-cell chronic lymphocytic leukemia, 1 B-cell prolymphocytic leukemia, 22 hairy cell leukemias, 4 large granular lymphocytic leukemias, 1 T-cell prolymphocytic leukemia, and non-Hodgkin's lymphomas (NHL): 10 splenic lymphomas with villous lymphocytes, 4 follicular lymphomas, 5 mantle cell lymphomas, 3 lymphoplasmacytic and 1 large cell NHL. The primary indications for surgery in this series were therapy-resistant disease (40%) and therapeutic splenectomy (38%). Postsplenectomy, 70% of patients had a complete hematological response, 23% had a partial response, and 7% were nonresponsive. Median treatment-free survival correlated with the hematologic response postsplenectomy and the underlying diagnosis. Better treatment-free survivals were seen in patients with lesser degrees of anemia and thrombocytopenia. Overall, improvements were more pronounced in the B-cell than in the T-cell disorders. Indications for further therapy, postoperative morbidity and mortality, and survival times are discussed along with a review of the literature. These findings advocate a continuing role for splenectomy in symptomatic lymphoid malignancies running with splenomegaly and hypersplenism.