Lithium enhances growth of human leukaemia cells in vitro

Clinical response and metabolic effects of lithium in 323 mood disorder patients

BACKGROUND

Lithium is the mainstay for the maintenance treatment of mood disorders (MD), but its efficacy needs to be weighed against its side effects profile. Here, we assessed retrospectively the clinical response to long-term lithium treatment, as well as the rate of associated metabolic side effects.

METHODS

Clinical data were collected from patients treated with lithium for at least 12 months at the Lucio Bini Center for Mood Disorders in Cagliari, Italy. Clinical response was determined as the difference in number of mood episodes and percent of illness time before and during lithium treatment. Symptomatic values of metabolic parameters (plasma levels of glucose, cholesterol, urea nitrogen [BUN], creatinine, TSH, white blood cells [WBC]), and Body Mass Index (BMI) were determined.

RESULTS

We studied 323 MD patients (60.2% women). The percent of illness time was significantly reduced for both depressive (F = 4.94, p<0.0001), and manic (F = 3.95, p < 0.0001) episodes, whereas the rates of episodes/year were significantly reduced for mania (F = 2.01, p = 0.02), but not for depression (F = 1.54, p = 0.06). Rates of MD patients with symptomatic values of metabolic parameters were 14.3% for WBC ≥10,000/µl, 26.9% for glucose levels ≥100 mg/dl, 54.2% for cholesterol levels ≥200 mg/dl, 7.5% for BUN ≥50 mg/dl, 21.9% for creatinine levels ≥1.2 mg/dl, and 20.9% for TSH levels ≥3.50 mU/l.

CONCLUSIONS

Long-term lithium treatment was clinically effective, but the rates of metabolic effects were substantial although some of them were also associated with older age. Lithium-treated patients should receive accurate clinical monitoring to decrease the impact of long-term side effects.

Review of lithium effects on immune cells

One of the remarkable discoveries in the field of psychopharmacology from late 1940s is Lithium (Li) that reminds of old but still gold. It continues to be a distinctive mood stabilizer that matches various standards recommended for mood stabilizers. Apart from this Li is also known to affect immune cell functions. Lithium response and regulations of different immune cells in bipolar patients, related immune disorders are not well defined. Here, we provide an overview of literature with regard to Li's effects on different immune cells. However, the use of Li is currently limited to bipolar disorders and there is no empirical evidence for immune cell disorders. The objective of this article is to provide the evaluations of Li responses towards the different immune cells based on the existing studies. Further, more studies are needed to understand the mechanistic basis and heterogeneous responses of Li's effect in bipolar, also unravel relative immune disorders.

Cytoprotective effect of lithium against spontaneous and induced apoptosis of lymphoid cell line MOLT-4

Lithium (Li) is still useful in the treatment of bipolar disorder. Cellular mechanisms of Li action are not fully understood and include some cytoprotective properties. Data concerning Li effect on the apoptotic mechanisms in cells other than neurons are fragmentary and contradictory. We have investigated anti-apoptotic activity of Li in a lymphoid derived MOLT-4 cell line. Spontaneous and camptothecin-induced apoptosis was analyzed in cells treated with 0-20 mM Li carbonate. Early apoptosis was identified as significant mitochondrial depolarization (JC-1 staining). Later stages of apoptosis were estimated with annexin V binding and by the proportion of cells containing sub-G1 amounts of DNA (PI staining). We have observed a biphasic effect of Li on the proportion of spontaneously apoptotic cells;namely, low (therapeutic) concentrations of Li had a significant effect stabilizing the mitochondrial membrane polarization, while 10 and 20mM Li increased apoptosis. The latter could be seen both as mitochondrial depolarization as well as an increased proportion of sub-G1 cells, accompanied by reduced proportion of S phase cells. Li at concentrations above 2 mM had a significant, dose-dependent, anti-apoptotic effect on the cells undergoing camptothecin induced apoptosis. In conclusion, demonstrated cytoprotective effect of Li is at least partially related to stabilization of mitochondrial membrane potential and to the reduction of DNA damaging effects in proliferating cells; both may form part of the mechanism through which Li is useful in therapy of bipolar disorder, but may have more general consequences.

Variant-specific patterns and humoral regulation of HP1 proteins in human cells and tissues

We have examined the occurrence and distribution of HP1α and HP1β under in vivo, ex vivo and in vitro conditions. Consistent with a non-essential role in heterochromatin maintenance, both proteins are diminished or undetectable in several types of differentiated cells and are universally downregulated during erythropoiesis. Variant-specific patterns are observed in almost all human and mouse tissues examined. Yet, the most instructive example of HP1 plasticity is observed in the lymph nodes, where HP1α and HP1β exhibit regional patterns that are exactly complementary to one another. Furthermore, whereas HP1α shows a dispersed sub-nuclear distribution in the majority of peripheral lymphocytes, it coalesces into large heterochromatic foci upon stimulation with various mitogens and IL-2. The effect of inductive signals on HP1α distribution is reproduced by coculture of immortalized T- and B-cells and can be confirmed using specific markers. These complex patterns reveal an unexpected plasticity in HP1 variant expression and strongly suggest that the sub-nuclear distribution of HP1 proteins is regulated by humoral signals and microenvironmental cues.

Cancer morbidity in psychiatric patients: influence of lithium carbonate treatment

The relationship between mental diseases and cancer development has been examined in a number of studies but the findings are still inconclusive and suffer from methodological problems. Studies conducted to examine the effect of lithium on malignant cells yielded inconsistent results. The study group included 609 patients treated by lithium carbonate and 2396 controls. A lower but non significant risk (RR = 0.79; CI = 0.17-3.60) to develop non-epithelial tumors was found among lithium carbonate treated psychiatric patients as compared to controls. A significantly (P = 0.05) inverse trend of cancer with lithium dose was observed. The risk of cancer development among each group of psychiatric patients was significantly lower than in the general population (RR = 0.68 for the lithium treated group versus 0.78 for controls). Mental patients have a lower cancer prevalence than the general population and lithium may have a protective effect.

Effects of lithium on dimethyl sulfoxide induced differentiation of HL-60 promyelocytic leukemia cells

The human promyelocytic leukemia cell line, HL-60, was used to investigate the effects of lithium on dimethyl sulfoxide (DMSO)-induced granulocytic differentiation of these cells. Dose-response studies showed an optimal increase of cellular proliferation when cells were incubated with 5 mM lithium for 5 days (127 +/- 5% of DMSO only treated cells). This enhancement in growth was preceded by significantly increased [methyl-3H]thymidine incorporation (143 +/- 4% of DMSO only treated controls) after 2 days. However, no significant changes in the ability of cells to reduce NBT could be detected irrespective of whether the cells were incubated with 1.25% (v/v) DMSO only, or with DMSO plus non-toxic concentrations (less than or equal to 10 mM) lithium. From the results obtained it would appear as if the arrest of growth induced by DMSO and the stimulation of proliferation effected by lithium occurs along independent pathways and that lithium exerts its mitogenic effect prior to the onset of terminal differentiation initiated by DMSO.

Leukemia in bipolar mood disorder: is lithium contraindicated?

The ability of lithium to cause leukocytosis has led to concern that it may also stimulate leukemic cells and hence cause the development of leukemia. This concern has mostly been associated with anecdotal case reports and in vitro studies. In contrast, epidemiology studies and in vivo data fail to affirm this concern. Overall, there is not enough information linking lithium to leukemic development to substantiate such an association.

A protein-free medium for the growth of hybridomas and other cells of the immune system

A protein-free medium, termed ABC, has been developed which essentially eliminates the need for serum proteins. ABC supports the long-term growth of murine hybridomas as well as other transformed cells of the immune system. The requirement of hybridoma growth for transferrin has been met by substituting the soluble organo-iron compound, sodium nitroprusside. Substantial improvement in the growth of hybridomas was afforded by the inclusion of 18 trace elements complexed to disodium ethylene diaminetetraacetate (EDTA). The medium was further improved by the inclusion of components not found in Ham's F12 medium or by raising the concentrations of existing low molecular weight components. Murine hybridomas can be cultured routinely in this protein-free medium in an anchorage-independent manner with doubling times generally under 24 h. Visualized on electrophoretic gels, levels of monoclonal antibody taken from those cultures often exceeded 80% of the total protein. The medium was also able to support the growth of HuT 78 and H9 cells as well as certain other transformed cells of the immune system. In addition, normal human peripheral blood lymphocytes, activated with phytohemagglutinin and cultured with 50 U/ml recombinant interleukin 2, could be grown for 2 wk with a 50-fold expansion over input cell number.

Failure of lithium to reduce period of neutropenia during induction therapy of acute myeloid leukemia

Fifty-four patients treated with daunorubicin, cytosine arabinoside and thioquanine for acute myeloid leukemia were randomly assigned to receive oral lithium carbonate 1200 mg daily or no lithium. The duration of neutropenia (less than 0.5 x 10(9)/L) was similar between controls (median 22.5 days) and patients treated with lithium (median 24 days). The number of remissions, relapse-free survival and survival were similar for the lithium treated and control groups of patients. There was no apparent clinical efficacy in the use of lithium to reduce the period of neutropenia in patients undergoing remission induction therapy for acute myeloid leukemia.

Modulation of interleukin 2 release from a primate lymphoid cell line in serum-free and serum-containing media

The ability to grow a clone of the cell line, MLA144, which is a constitutive producer of interleukin 2 (IL-2), in serum-free medium permitted the study of the direct effect of various agents on cell growth and IL-2 production in a homogeneous population. Bovine serum albumin (BSA) at 4 mg/ml was optimal for cell growth and IL-2 production. Selenium at 10 ng/ml enhanced IL-2 production nearly twofold and lithium at 42 ng/ml also enhanced IL-2 production by nearly twofold. Neither compound at these levels altered cellular proliferation. Two other compounds, iron and zinc, known to be associated with cellular proliferation and/or immunoregulation did not alter IL-2 production. Catalase or horseradish peroxidase was able to substitute for BSA and maintain the long-term growth of the MLA144 clone with only a 30% decrease in the rate of cellular proliferation and a 50% decrease in IL-2 production compared to cells maintained in the serum-free formulation with BSA. Addition of 0.5 mg of BSA to the catalase serum-free formulation increased the production of IL-2 to 70% of that of cells cultured in the BSA-containing serum-free formulation. The catalase-containing serum-free formulation has the advantage of consisting of only three proteins, catalase, insulin, and transferrin, at a very low protein content. The catalase-containing serum-free medium also supported the long-term growth of a human T-cell line, HSB-2.

Granulocytopenia and cancer therapy. Past problems, current solutions, future challenges

Granulocytopenia has been closely associated with cancer and its treatment. The risk for a life-threatening infection when the granulocyte count falls below 500/mm3 not only is an important complication of therapy and a major cause of death in cancer patients but also plays an important role in the design, schedule, and doses of cancer treatment regimens. While granulocytopenia remains an unavoidable complication of current therapy, improved recognition of patients at risk and prompt initiation of aggressive supportive care have had a significant impact on reducing its infection-related morbidity and mortality. In particular, early empiric antibiotic therapy when the granulocytopenic patient becomes febrile has resulted in a significant reduction in the early mortality from undiagnosed bacterial infections. New antibiotics (extended-spectrum penicillins, third generation cephalosporins) provide new options because of their broad efficacy and potential for reducing the toxicity of antimicrobial therapy. However, as bacterial infections have become better controlled, fungi have emerged as important pathogens. Early aggressive empiric antifungal therapy appears to have reduced infectious mortality, although the repertoire of effective antifungal agents is quite limited. Considerable efforts have been expended in trying to replenish granulocytes by transfusion in infected patients, but technical deficiencies have limited this approach. Current and future efforts are directed toward refining management as well as to developing methods to improve host defenses and provide prophylaxis against infections. If the full potential of current cancer therapy is to be realized, control of granulocytopenia and the prevention of infections are essential goals.

Limitations of current antimicrobial therapy in the immunosuppressed host: looking at both sides of the coin

During the last twenty years there have been considerable advances in the antimicrobial management of the immunosuppressed host. These include the development of antibiotics with broad-spectrum and high bactericidal activity along with the appreciation of the importance of promptly initiating empiric antibiotic therapy when the granulocytopenic patient becomes febrile and continuing them (in some cases with empiric antifungal therapy) until the resolution of granulocytopenia. Nonetheless, infection still remains a major cause of death in compromised hosts and a number of limitations of therapy persist. Included are a limited repertoire of drugs active against fungi (particularly Aspergillus) as well as certain viruses (for example, cytomegalovirus) and the inability to eradicate certain sites of infection (for example, Pseudomonas pneumonia) even with effective agents. Current investigations are focused on developing new antimicrobial agents as well as methods to improve the altered host defenses of immunosuppressed patients, both as adjuvants to therapy and, eventually, as a means to prevent infectious complications.

Lithium treatment in adults with acute myeloid leukemia receiving chemotherapy

To determine whether lithium can shorten chemotherapy-induced neutropenia, 35 adult patients with newly diagnosed acute myeloid leukemia undergoing initial chemotherapy were randomized either to receive oral lithium started at the time of biopsy-proven hypoplasia or to receive no lithium. This study failed to show statistically significant shortening of the duration of chemotherapy-induced neutropenia in the lithium treatment group.

Massive retroperitoneal lymphadenopathy as a terminal event in hairy cell leukaemia

A case of hairy cell leukaemia complicated as a terminal event by massive retroperitoneal lymphadenopathy is described. The patient had recently been treated with lithium carbonate and had previously been demonstrated to suffer from a systemic vasculitis, either or both of which may have contributed to the development of this rare complication.