Daratumumab plus lenalidomide and dexamethasone versus lenalidomide and dexamethasone in relapsed or refractory multiple myeloma: updated analysis of POLLUX.

In the POLLUX study, daratumumab plus lenalidomide/dexamethasone significantly reduced risk of progression/death versus lenalidomide/dexamethasone alone in relapsed/refractory multiple myeloma. We provide one additional year of follow up and include the effect on minimal residual disease and in clinically relevant subgroups. After 25.4 months of follow up, daratumumab plus lenalidomide/dexamethasone prolonged progression-free survival versus lenalidomide/dexamethasone alone (median not reached vs 17.5 months; hazard ratio, 0.41; 95% confidence interval, 0.31-0.53; P<0.0001). The overall response rate was 92.9% versus 76.4%, and 51.2% versus 21.0% achieved a complete response or better, respectively (both P<0.0001). At the 10-5 sensitivity threshold, 26.2% versus 6.4% were minimal residual disease-negative, respectively (P<0.0001). Post hoc analyses of clinically relevant patient subgroups demonstrated that progression-free survival was significantly prolonged for daratumumab plus lenalidomide/dexamethasone versus lenalidomide/dexamethasone regardless of number of prior lines of therapy. Patients previously treated with lenalidomide or thalidomide and those refractory to bortezomib received similar benefits (all P<0.01). Treatment benefit with daratumumab plus lenalidomide/dexamethasone was maintained in high-risk patients (median progression-free survival 22.6 vs 10.2 months; hazard ratio, 0.53; 95% confidence interval, 0.25-1.13; P=0.0921) and patients with treatment-free intervals of >12 and ≤12 months and >6 and ≤6 months. No new safety signals were observed. In relapsed/refractory multiple myeloma patients, daratumumab plus lenalidomide/dexamethasone continued to improve progression-free survival and deepen responses versus lenalidomide/dexamethasone. Trial Registration: clinicaltrials.gov identifier: 02076009.

High concordance in grading reticulin fibrosis and cellularity in patients with myeloproliferative neoplasms.

The myeloproliferative neoplasms primary myelofibrosis, polycythemia vera, and, rarely, essential thrombocythemia are characterized by variable degrees of bone marrow fibrosis, either at presentation or upon progression. The increasing use of emerging therapies that may alter disease biology and morphology demands accurate and reproducible assessment of fibrosis grade. To assess concordance of hematopoietic cellularity and fibrosis grading, three hematopathologists independently evaluated a total of 728 bone marrow biopsies from 261 patients with myeloproliferative neoplasms on three clinical trials using fedratinib (SAR302503), a JAK2 inhibitor, including 249 taken at baseline and 479 on therapy. Concordance between the pathologists was evaluated by Pearson correlation coefficient (cellularity) and unweighted kappa statistic (fibrosis grade). There was high correlation of cellularity assessment (r=0.92) and fibrosis grading (kappa=0.83) between the three pathologists. Concordance with World Health Organization (WHO) grade 3 samples was higher compared with grades 0, 1, and 2. Concordance of fibrosis grading in pretreatment samples was superior to that of post-treatment samples (kappa=0.83 and 0.79, respectively, P=0.023). Our analysis suggests that the updated 2008 WHO reticulin fibrosis grading system is highly reproducible, even in patients undergoing JAK2 inhibitor therapy. This system is practically applicable to establish baseline fibrosis grade as well as changes in fibrosis in subsequent samples on therapy.

A Phase I trial of the kinesin spindle protein (Eg5) inhibitor AZD4877 in patients with solid and lymphoid malignancies.

BACKGROUND: This Phase I study assessed the safety and maximum tolerated dose (MTD) of the kinesin spindle protein inhibitor AZD4877 in patients with relapsed/refractory solid tumors and lymphoma. METHODS: In this multicenter study, a standard 3 + 3 dose-escalation design was used. AZD4877 was given as an intravenous infusion on days 1, 4, 8 and 11 of each 21-day cycle. Responses were assessed with CT scans +/- PET after 6 and 12 weeks, then every 12 weeks while on therapy. An additional four patients with lymphoma were enrolled at the MTD. RESULTS: 29 patients were enrolled and 22 patients received at least one dose of AZD4877 and were evaluable for safety. The MTD was 11 mg. Dose-limiting toxicity was neutropenia (n = 2 patients, 15 mg cohort). The most common adverse events were grade 1/2 fatigue, nausea, neutropenia and dyspnea. AZD4877 exposure generally increased with dose, with mean elimination half-life approximately 16 h at the MTD. Pharmacodynamic analyses demonstrated moderate correlation between plasma drug concentrations at 6 or 24 h and monoaster formation in peripheral blood mononuclear cells (PBMCs). CONCLUSIONS: AZD4877 is generally well-tolerated with pharmacodynamic evidence of target inhibition in circulating PBMCs.

A novel orally active small molecule potently induces G1 arrest in primary myeloma cells and prevents tumor growth by specific inhibition of cyclin-dependent kinase 4/6.

Cell cycle deregulation is central to the initiation and fatality of multiple myeloma, the second most common hematopoietic cancer, although impaired apoptosis plays a critical role in the accumulation of myeloma cells in the bone marrow. The mechanism for intermittent, unrestrained proliferation of myeloma cells is unknown, but mutually exclusive activation of cyclin-dependent kinase 4 (Cdk4)-cyclin D1 or Cdk6-cyclin D2 precedes proliferation of bone marrow myeloma cells in vivo. Here, we show that by specific inhibition of Cdk4/6, the orally active small-molecule PD 0332991 potently induces G(1) arrest in primary bone marrow myeloma cells ex vivo and prevents tumor growth in disseminated human myeloma xenografts. PD 0332991 inhibits Cdk4/6 proportional to the cycling status of the cells independent of cellular transformation and acts in concert with the physiologic Cdk4/6 inhibitor p18(INK4c). Inhibition of Cdk4/6 by PD 0332991 is not accompanied by induction of apoptosis. However, when used in combination with a second agent, such as dexamethasone, PD 0332991 markedly enhances the killing of myeloma cells by dexamethasone. PD 0332991, therefore, represents the first promising and specific inhibitor for therapeutic targeting of Cdk4/6 in multiple myeloma and possibly other B-cell cancers.

Telomere-driven karyotypic complexity concurs with p16INK4a inactivation in TP53-competent immortal endothelial cells.

Critically short telomeres promote chromosomal fusions, which in TP53-defective cells initiate the formation of cytogenetic aberrations that are typical of human cancer cells. Expression of the enzyme telomerase stabilizes normal and aberrant chromosomes by maintaining telomere length. However, previous investigations, including our own, have shown that overexpression of telomerase reverse transcriptase (hTERT) does not prevent net telomere shortening in human endothelial cells. In the present study, two mass cultures of hTERT-transduced bone marrow endothelial cells (BMhTERT) and 26 clones were employed to further investigate the immortalization process and consequences of telomere shortening. Eighty-five percent (22 of 26) of the clones and both mass cultures were immortalized. However, cytogenetic analyses revealed recurring cytogenetic aberrations in the mass cultures and 12 representative clones. Several of the recurring aberrations, including +5p, +11, -13, +19, and +20, and nonreciprocal translocations involving 17p and 2p were previously implicated in human carcinogenesis. One mass culture and a subset of clones (5 of 12) had complex karyotypes, characterized by cytogenetic heterogeneity and at least five chromosomal abnormalities. p16(INK4a) was silenced exclusively in the five clones and mass culture with complex karyotypes, whereas the p53/p21(cip1) pathway was defective in only one clone. Telomere dysfunction was implicated in the evolution of complex karyotypes by the presence of anaphase bridges, telomere associations, and dicentric chromosomes. These results show that complex karyotypes can evolve in TP53-competent cells and provide evidence that p16(INK4a) functions as a gatekeeper to prevent telomere-driven cytogenetic evolution. These investigations provide new insight to the role of p16(INK4a) as a tumor suppressor.

Long-term bovine hematopoietic engraftment with clone-derived stem cells.

Therapeutic cloning by somatic cell nuclear transfer offers potential for treatment of a wide range of degenerative disease. Nuclear transplantation with neo (r)-marked somatic nuclei from 10-13-year-old cows was used to generate cloned bovine fetuses. Clone fetal liver (FL) hematopoietic stem cells (HSC) were transplanted into two busulfan-treated and one untreated nuclear donor cows. Hematopoiesis was monitored over 13-16 months by in vitro progenitor and HSC assays. Chimerism was demonstrated by PCR in blood, marrow, lymph nodes, and endothelium, peaking at levels of 9-17% in blood granulocytes but at lower levels in lymphocyte subsets (0.1-0.01%). Circulating progenitors showed high levels of chimerism (up to 60% neo (r+)) with persisting fetal features. At sacrifice, the animal that had no pre-transplant myelosupression showed persisting donor cells in blood and lymph nodes, and in marrow 0.25% of progenitor cells and a detectable fraction of stem cells were neo (r+). The fetal HSC showed a 10-fold competition advantage over adult HSC. Cloning generated histocompatible HSC capable of long-term multilineage engraftment in a large animal model.

Determination of telomerase activity and telomere length.

Telomerase is an enzyme that has been attracting much attention in recent years because its activities are so central to the processes of malignant transformation. It is a reverse transcriptase enzyme that can synthesize telomeric DNA using its own RNA component as a template. Without telomerase, telomeres will shorten until, at a critical length, cells enter senescence and die. The low level or absence of telomerase activity in most nonneoplastic tissues and somatic cells, and its presence in almost all malignant tumors is thus of great interest for potential diagnostic, prognostic, and therapeutic applications in the management of human cancer. It has been documented that high telomerase activity and short telomere length correlate with poor prognosis in patients with multiple myeloma, and antitelomerase therapy has become a novel therapeutic approach for the disease. Thus, determination of telomerase activity and telomere length is essential in the study of cancer. In this chapter, we provide a standard telomeric repeat amplification protocol for telomerase activity assay and a Southern blot terminal restriction fragment protocol for telomere length assay. We also discuss comparison with related assay methods.

Antibody targeting of the insulin-like growth factor I receptor enhances the anti-tumor response of multiple myeloma to chemotherapy through inhibition of tumor proliferation and angiogenesis.

Although many multiple myeloma (MM) patients initially respond to cytotoxic therapy, most eventually relapse. Novel therapeutic strategies employing a combination of chemotherapy with targeted biologics may significantly enhance the response of tumor cells to treatment. We tested a fully human anti-IGF-IR antibody (A12) against MM, and showed specific inhibition of IGF-I or serum-induced IGF-IR signaling in MM cells in vitro. The A12 as a single agent was demonstrated to exert modest to significant inhibition of tumor growth in vivo in various subcutaneous xenograft MM models. The A12 was also evaluated in a disseminated xenograft MM.1S NOD/SCID model as monotherapy or in combination with other drugs (bortezomib, melphalan) currently in clinical use. The tumor burden, as determined by luciferase bioimaging, was sharply decreased, and overall survival significantly prolonged when the therapies were combined. Immunohistochemical analysis demonstrated that the A12 treated tumors had significantly decreased vascularization compared to control tumors. Furthermore, most MM lines constitutively secreted significant quantities of VEGF, and this was enhanced following IGF-I treatment. Inhibition of IGF-IR by the A12 in vitro suppressed both constitutive and IGF-I-induced secretion of VEGF, indicating that a putative anti-angiogenic mechanism associated with the A12 treatment may contribute to its anti-tumor effect.

Spectral karyotyping demonstrates genetically unstable skin-homing T lymphocytes in cutaneous T-cell lymphoma.

We initially established cell lines from skin biopsies from four patients (MF8, MF18, MF19 and MF31) in early stages of cutaneous T-cell lymphoma (CTCL) in 1999. After 3 weeks of culture, skin-homing T lymphocytes were stimulated with phytohaemagglutinin. Metaphase spreads were analysed using spectral karyotyping (SKY), a molecular cytogenetic technique. MF18 and MF19 had predominantly normal karyotypes. MF8 had recurrent numerical aberrations resulting in two T lymphocyte clones: one with trisomy 21 (12/20 cells) and the other with monosomy chromosome 22 (3/20 cells). MF8 also exhibited a clonal deletion, del(5)(p15.1), as well as multiple non-clonal structural aberrations. MF31 had a clonal deletion, del(17)(p12) and other non-clonal deletions involving chromosomes 2, 5, 10, 11. MF18 had a single abnormal cell that contained two reciprocal translocations t(1;2)(q32;p21) and t(4;10)(p15.2;q24). In 2001, three of the original patients had new skin biopsies taken and cell lines were established. SKY analysis revealed the continued presence of a T-cell clone in MF8 with trisomy 21 (4/20 cells). Additionally, a new clone was seen with a del(18)(p11.2) (17/20 cells). MF31 had only one aberrant cell with a del(17)(p12). MF18 had a clonal deletion, [del(1)(p36.1) in 3/20 cells] and non-clonal aberrations involving chromosomes 3, 4, 5, 6, 12, 13, 17 and 18. Thus, three of four patients continued to show numerous numerical and structural aberrations, both clonal and non-clonal, with only MF8 having a recurring T lymphocyte clone (+21). Our findings demonstrate high genetic instability among skin-homing T lymphocytes even in early stages of CTCL. We did not see genetic instability or evidence of clones in cell lines from a patient with atopic dermatitis and one with psoriasis.

Skin-homing CD8+ T lymphocytes show preferential growth in vitro and suppress CD4+ T-cell proliferation in patients with early stages of cutaneous T-cell lymphoma.

A total of 27 T-lymphocyte cell strains were established from skin biopsies of 24 patients with various stages of cutaneous T-cell lymphoma (CTCL) by addition of the T-cell growth factors interleukin (IL)-2 and IL-4. Cellular proliferation and phenotypic changes were measured over 3 months in culture, and T-cell clones were studied using T-cell receptor-? re-arrangement techniques. An average outgrowth of 134 million T-lymphocytes from a 4-mm skin biopsy was observed over 2 months. Initially, most T-cells expressed the CD4+ phenotype. In 17 cell strains from patients with early CTCL a statistically significant predominance of CD8+ T-lymphocytes developed over 8-weeks' culture, indicating that CD8+ T-cells controlled the growth of CD4+ T cells, whereas CD4+ T-cells were predominant in cell strains from advanced CTCL (p <0.05). TCR-? re-arrangement studies revealed, on average, 12 T-cell clones per cell strain, which was reduced over time to 6 T-cell clones per cell strain. Lymphocytes from peripheral blood could kill lymphocytes from an autologous cell strain, suggesting the presence of autoreactive cytotoxic T-cells. Our study suggests how skin-homing CD8+ T-lymphocytes from patients with early stage CTCL can suppress the in vitro growth of skin-homing CD4+ T-lymphocytes, indicating immune surveillance.

Investigation of antitumor effects of synthetic epothilone analogs in human myeloma models in vitro and in vivo.

26-Trifluoro-(E)-9,10-dehydro-12,13-desoxyepothilone B [Fludelone (Flu)] has shown broad antitumor activity in solid tumor models. In the present study, we showed, in vitro, that Flu significantly inhibited multiple myeloma (MM) cell proliferation (with 1-15 nM IC50), whereas normal human bone marrow stromal cells (HS-27A and HS-5 lines) were relatively resistant (10- to 15-fold higher IC50). Cell-cycle analysis demonstrated that Flu caused G2/M phase arrest and induced cell apoptosis. After Flu treatment, caspase-3, -8, and -9 were activated, cytochrome c and second mitochondrial-derived activator of caspase were released to the cytosol, and c-Jun N-terminal kinase was activated, indicating that mitochondria were involved in the apoptosis. Flu toxicity to human hematopoietic stem cells was evaluated by CD34+ cell-apoptosis measurements and hematopoietic-progenitor assays. There was no significant toxicity to noncycling human CD34+ cells. We compared the efficacy of Flu with the epothilone analog 12,13-desoxyepothilone B (dEpoB) in xenograft nonobese diabetic/severe combined immunodeficient mouse models with subcutaneous or disseminated MM. Flu caused tumor disappearance in RPMI 8226 subcutaneous xenografts after only five doses of the drug (20 mg/kg of body weight), with no sign of relapse after 100 d of observation. In a disseminated CAG MM model, mice treated with Flu had a significantly decreased tumor burden, as determined by bioluminescence imaging, and prolonged overall survival vs. mice treated with dEpoB or vehicle control, indicating that Flu may be a promising agent for MM therapy.

Enforced activation of STAT5A facilitates the generation of embryonic stem-derived hematopoietic stem cells that contribute to hematopoiesis in vivo.

Little is known about the molecular mechanisms that direct the transition from primitive to definitive hematopoiesis. In this study, we cocultured murine embryonic stem (ES) cells on OP9 stroma to induce hematopoietic differentiation as a model to study factors involved in the generation of adult hematopoietic stem cells (HSCs). Overexpression of the constitutively activated mutant signal transducer and activator of transcription (STAT) 5A(1*6) in ES cells facilitated the generation of cells that expressed the endothelial-hemangioblast marker Flk-1 within 5 days of coculture on OP9. The first CD41+/ CD45+/c-Kit+/(Flk-1)- hematopoietic cells arose in our culture conditions between days 5 and 7. Persistent activation of STAT5A greatly enhanced the generation of hematopoietic progenitors compared with controls, as determined by colony assays in methylcellulose. Moreover, whereas controls generated only a short transient wave of hematopoiesis lasting less than 3 weeks, expression of STAT5A(1*6) resulted in the generation of hematopoietic cobblestone area-forming cells (CAFCs) on OP9 that could be serially passaged onto new OP9, giving rise to second and third CAFCs that generated hematopoietic progenitors for > or = 5 weeks, indicating a role for STAT5A in HSC self-renewal in vitro. Several definitive hematopoietic genes were upregulated by STAT5A (1*6), as well as Runx1/AML1, vascular endothelial growth factor, oncostatin M receptor, HoxB4, Wnt5A, Delta-like-1, and Bmi-1. Furthermore, ES-derived hematopoietic cells expressing STAT5A(1*6) contributed to myeloid-lymphoid hematopoiesis in primary and secondary nonobese diabetic-severe combined immunodeficiency recipients, although no donor-derived cells could be detected after 7 weeks in the secondary recipients. These data indicate that a persistent activation of STAT5A allows the generation of ES-derived HSCs that can, at least for an intermediate period, contribute to hematopoiesis in vivo.

Telomerase and telomere length in multiple myeloma: correlations with disease heterogeneity, cytogenetic status, and overall survival.

We have investigated the significance of telomerase activity (TA) and telomere length (TL) in multiple myeloma (MM). The analyses were undertaken on CD138+ MM cells isolated from the marrow of 183 patients either at diagnosis or in relapse. There was heterogeneity in telomerase expression; 36% of the patients had TA levels comparable to those detected in normal plasma cells, and 13% of patients had levels 1- to 4-fold greater than in a neuroblastoma cell line control. The TL of MM cells was significantly shorter than that of the patients' own leukocytes; in 25% of patients, the TL measured less than 4.0 kbp. Analysis of TL distribution indicated selective TA-mediated stabilization of shorter telomeres when mean TL fell below 5.5 kbp. Unusually long (10.8-15.0 kbp) telomeres were observed in 7 patients, and low TA was observed in 5 of 7 patients, suggesting the operation of a TA-independent pathway of telomere stabilization. A strong negative correlation existed between TA and TL or platelet count. TL negatively correlated with age and with interleukin-6 (IL-6) and beta2-microglobulin levels. Various cytogenetic abnormalities, including those associated with poor prognosis, strongly correlated with TA and, to a lesser extent, with short TL. High TA and short TL defined a subgroup of patients with poor prognosis. At 1 year the survival rate in patients with TA levels lower than 25% of neuroblastoma control and TL greater than 5.5 kbp was 82%, whereas in patients with higher TA and shorter TL the survival rate was 63% (P =.004). The 2-year survival rate for patients with TA levels lower than 25% was 81%, and it was 52% in those with higher TA levels (P <.0001).

Elevated telomerase activity and minimal telomere loss in cord blood long-term cultures with extensive stem cell replication.

Telomerase activity, telomere length, stem/progenitor cell production, and function of CD34+ cells from cord blood (CB), bone marrow, and mobilized peripheral blood were evaluated in long-term cultures. CB cells were cultured either on OP-9 stromal cells transduced with an adenovector expressing thrombopoietin (TPO) or stimulated by a cytokine cocktail in the absence of stroma, with, in one method, CD34+ cells reisolated at monthly intervals for passage. Continuous expansion of stem cells as measured by in vitro cobblestone area and secondary colony-forming assays was noted for 18 to 20 weeks and by severe combined immunodeficiency (SCID)-repopulating cells (SRCs), capable of repopulating and serially passage in nonobese diabetic/SCID mice, for 16 weeks. Despite this extensive proliferation, telomere length initially increased and only at late stages of culture was evidence of telomere shortening noted. This telomere stabilization correlated with maintenance of high levels of telomerase activity in the CD34+ cell population for prolonged periods of culture. Cytokine-stimulated cultures of adult CD34+ cells showed CD34+ and SRC expansion (6-fold) for only 3 to 4 weeks with telomere shortening and low levels of telomerase. There is clearly a clinical value for a system that provides extensive stem cell expansion without concomitant telomere erosion.

Telomerase inhibition with an oligonucleotide telomerase template antagonist: in vitro and in vivo studies in multiple myeloma and lymphoma.

The effects of telomerase inhibition with an oligonucleotide N3' --> P5' thiophosphoramidate (GRN163) complementary to the telomerase template region were examined on human multiple myeloma (MM) and non-Hodgkin lymphoma (NHL) cell lines, primary MM cells, and tumor xenografts. GRN163 treatment reduced telomerase levels in all cells and induced more rapid telomeric shortening. Continuous GRN163 treatment for 7 to 14 days resulted in proliferative arrest, morphologic changes, and apoptosis characteristic of cell crisis in tumor cell lines with short (1.7-5.4 kb) but not long (9-11 kb) telomeres. Intratumoral administration of GRN163 also inhibited the growth of MM and NHL xenografts established from cell lines with short telomeres (Hs602 lymphoma, 2.7 kb; CAG myeloma, 2.7 kb) and increased tumor apoptosis. However, GRN163 therapy of NHL xenografts established from cells with long telomeres (11.0 kb) had equivocal effects on tumor growth and did not induce apoptosis during this time frame. Systemic daily intraperitoneal administration of GRN163 in myeloma xenografts with short telomere lengths also decreased tumor telomerase levels and reduced tumor volumes. These data demonstrate that telomerase is important for the replication of mature B-cell neoplasia by stabilizing short telomeres, and they suggest that telomerase inhibition represents a novel therapeutic approach to MM and NHL.

Maintaining the self-renewal and differentiation potential of human CD34+ hematopoietic cells using a single genetic element.

Hematopoiesis is a complex process involving hematopoietic stem cell (HSC) self-renewal and lineage commitment decisions that must continue throughout life. Establishing a reproducible technique that allows for the long-term ex vivo expansion of human HSCs and maintains self-renewal and multipotential differentiation will allow us to better understand these processes, and we report the ability of the leukemia-associated AML1-ETO fusion protein to establish such a system. AML1-ETO-transduced human CD34+ hematopoietic cells routinely proliferate in liquid culture for more than 7 months, remain cytokine dependent for survival and proliferation, and demonstrate self-renewal of immature cells that retain both lymphoid and myeloid potential in vitro. These cells continue to express the CD34 cell surface marker and have ongoing telomerase activity with maintenance of telomere ends, however they do not cause leukemia in nonobese diabetic-severe combined immunodeficiency (NOD/SCID) mice. Identification of the signaling pathways that are modulated by AML1-ETO and lead to the self-renewal of immature human progenitor cells may assist in identifying compounds that can efficiently expand human stem and progenitor cells ex vivo.

The migrastatin family: discovery of potent cell migration inhibitors by chemical synthesis.

The first asymmetric total synthesis of (+)-migrastatin (1), a macrolide natural product with anti-metastatic properties, has been accomplished. Our concise and flexible approach utilized a Lewis acid-catalyzed diene aldehyde condensation (LACDAC) to install the three contiguous stereocenters and the trisubstituted (Z)-alkene of migrastatin (2 + 3 --> 21). Construction of the two remaining stereocenters and incorporation of the glutarimide-containing side chain was achieved by an anti-selective aldol addition of propionyl oxazolidinone 28 to angelic aldehyde 27, followed by a Horner-Wadsworth-Emmons (HWE) coupling of 32 with glutarimide aldehyde 5. Finally, the assembly of the macrocycle was realized by a highly (E)-selective ring-closing metathesis (35 --> 37). Utilizing the power of diverted total synthesis (DTS), a series of otherwise inaccessible analogues was prepared and evaluated for their potential as tumor cell migration inhibitors in several in vitro assays. These studies revealed a dramatic increase in activity when the natural motif was considerably simplified, presenting macrolactones 45 and 48, as well as macrolactam 55, macroketone 60, and CF(3)-alcohol 71 as promising anti-metastatic agents.