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Researchers have developed a new approach to drug discovery that takes advantage of the gene expression signatures of tumors to generate potential drug matches. A proof-of-principle of this technique revealed a potential new combination therapy for children with acute lymphocytic leukemia (ALL).

In 2004, multiple myeloma was diagnosed in more than 15,000 peoplein the United States and will account for approximately 20% of deathsdue to hematologic malignancies. Although traditional therapies suchas melphalan (Alkeran)/prednisone, combination chemotherapy withVAD (vincristine, doxorubicin [Adriamycin], and dexamethasone), andhigh-dose chemotherapy with stem cell transplantation have shownsome success, median survival remains between 3 to 5 years. Treatmentoptions for patients with multiple myeloma have increased in recentyears, with the promise of improvement in survival. New agents, suchas the proteasome inhibitor bortezomib (Velcade), the antiangiogenicand immunomodulator thalidomide (Thalomid) and its analogs, suchas lenalidomide (Revlimid), together with other small molecules, includingarsenic trioxide (Trisenox), and other targeted therapies, havebeen studied alone and in combination with other antineoplastic therapies,either as induction therapy prior to stem cell transplantation or inpatients with relapsed disease. Bortezomib recently was approved inthe United States for the treatment of multiple myeloma in patientswho have received at least one prior therapy. The use of bortezomibbasedregimens as front-line therapy as well as the use of other agentsin multiple myeloma remain under investigation, and approvals forboth thalidomide and lenalidomide are hoped for soon, with the overallprospect of patient outcome continuing to be increasingly positive.

Research into the genetics of ocular disease is paying off with discoveries of new genes associated with both common and rare eye conditions. Gene therapy, however, could be 5 to 10 years away for many eye diseases. In this first of a two-part series, researchers explain the progress in age-related macular degeneration (AMD), Leber's congenital amaurosis, and familial exudative vitreoretinopathy (FEVR). In the second half of the series, gains in glaucoma, myopia, and retinitis pigmentosa will be covered as well as a promising therapy for AMD—RNA interference.

Kauh and colleagues nicely outlinethe major problems facingclinicians who treat humanimmunodeficiency virus (HIV)-positivepatients with squamous cell carcinomaof the anus. This is a highly curabledisease with combined-modality therapy,though the HIV-positive populationpresents unique challenges. Weagree with the approaches outlined bythe authors and would also like to emphasizeseveral principles in the managementof anal cancer.

Drs. Laskin and Sandler havedone an excellent job of summarizingthe results of chemotherapyin the treatment of stageIV non–small-cell lung cancer. Theyhave pointed out that a meta-analysispublished in 1995 showed that chemotherapyprovided a modest survivaladvantage compared to supportivecare alone. In addition, they have citedstudies that have shown the treatmentis cost-effective and that it relieveslung cancer–related symptoms.They have thoroughly discussed thefact that multiple phase III trials testingnewer chemotherapy doubletsshow slightly different toxicity profiles with virtually identical efficacy,and that giving more than four coursesof therapy with regimens that consistof three or more drugs does notprovide significant benefit.

The identification of key signaltransduction pathways and, inparticular, specific proteins thatare involved in the regulation of cancercell growth has provided unprecedentedopportunities for researchersinterested in targeted cancer treatment.The identification of molecular target-specific therapy offers the potentialof maximal therapeutic benefitwhile minimizing toxicity to normalcells. The accomplishment that led tothe sequencing and analysis of theentire human genome in 2001 has providedresearchers with the basic criticaltools to begin to identify anddifferentiate cancer from normal tissueat the genetic level.[1,2] Whilethe implications of this landmarkachievement are still being realized,it has become evident that the identificationof critical genes and proteinsinvolved in cell division and growthare just the beginning. The complexrelationships between multiple signaltransduction pathways, the surroundingtumor microenvironment, andpathways involved in immune-systemregulation have gained new appreciation.The ability to manipulate thesemultiple interactive systems with targetedtherapies represents a new treatmentparadigm in oncology.

Lung cancer continues to be themost common cause of cancerdeaths in the United States forboth men and women. Unfortunately,the majority of patients presentwith local or distant disease at thetime of diagnosis. Surgical resectioncontinues to offer the best chance forlong-term survival; however, less than25% of patients have surgically resectabledisease. Even after surgicalresection for early-stage disease a significantnumber of patients will developrecurrent disease, with themajority being distant in nature. Developmentof distant disease usuallyproves to be the terminal event inmost patients. Multiple treatmentmodalities have been investigated asadjuvant therapy to decrease the incidenceof distant disease after completesurgical resection. Untilrecently, no modality has shown asurvival advantage in patients afterresection for non–small-cell lung cancer(NSCLC).

Squamous cell anal cancer remains an uncommon entity; however,the incidence appears to be increasing in at-risk populations, especiallythose infected with human papillomavirus (HPV) and human immunodeficiencyvirus (HIV). Given the ability to cure this cancer using synchronouschemoradiotherapy, management practices of this disease arecritical. This article considers treatment strategies for HIV-positive patientswith anal cancer, including the impact on chemoradiation-inducedtoxicities and the role of highly active antiretroviral therapy in the treatmentof this patient population. The standard treatment has beenfluorouracil (5-FU) and mitomycin (or cisplatin) as chemotherapy agentsplus radiation. Consideration to modifying the standard treatment regimeis based on the fact that patients with HIV tend to experience greatertoxicity, especially when CD4 counts are below 200; these patients alsorequire longer treatment breaks. Additional changes to the chemotherapydosing, such as giving 5-FU continuously and decreasing mitomycin dose,are evaluated and considered in relation to radiation field sizes in an effortto reduce toxicity, maintain local tumor control, and limit need forcolostomy. The opportunity for decreasing the radiation field size andusing intensity-modulated radiation therapy (IMRT) is also considered,particularly in light of the fact that IMRT provides dose-sparing whilemaximizing target volume dose to involved areas. The impact of the immunesystem in patients with HIV and squamous cell carcinoma of theanus and the associated response to therapy remains unknown. Continuedstudies and phase III trials will be needed to test new treatment strategiesin HIV-infected patients with squamous cell cancer of the anus todetermine which treatment protocols provide the greatest benefits.

Because of the high rate of distant disease recurrence, the 5-yearsurvival of patients who have undergone complete surgical resectionof localized non–small-cell lung cancer (NSCLC) is approximately 50%.Initial results from early studies of adjuvant postoperative chemotherapyreported an adverse effect of alkylating agent and older chemotherapyregimens on survival. Cisplatin-based combinations were the first toshow a survival advantage. A 1995 meta-analysis of these studies suggesteda 13% reduction in the hazard ratio for death (HR = 0.87), leadingto a 5% survival benefit at 5 years. Still, these trials involved limitednumbers of patients (N = 1,394), and the results failed to reach statisticalsignificance (P = .08). Of the five largest subsequent randomizedtrials of platinum-based adjuvant therapy, three showed a significantsurvival advantage. Although it is impossible to determine the reasonsfor the differing outcomes of these studies, several key features distinguishthem, and the data suggest that medically fit patients with resectedstage IB or II NSCLC should be offered chemotherapy with a platinum/new drug combination.

ORLANDO - Thalidomide (Thalomid) added to intensive front-line therapy for multiple myeloma proved superior to intensive therapy alone in a randomized trial led by Bart Barlogie, MD, PhD, director, University of Arkansas Myeloma Institute for Research & Therapy, Little Rock, and lead investigator of the trial. He reported the findings at the American Society of Clinical Oncology 41st Annual Meeting (abstract 6502). The researchers also found that cytogenetic abnormalities were strongly associated with response and survival. Thalidomide benefited only patients without the abnormalities. The phase III trial randomized 668 newly diagnosed patients to receive Total Therapy 2, which involves several rounds of stem cell transplants and chemotherapy, with or without thalidomide, given from the beginning of treatment and continued until recurrence.

About 172,570 new cases ofnon–small-cell lung cancer(NSCLC) are expected to bediagnosed in 2005 in the United States,and almost as many will die of thedisease. Patients with effusions or metastaticdisease are candidates for combinationchemotherapy. The regimensof choice are platinum-based combinationchemotherapy schedules. Giventhat most patients will experience diseaseprogression despite their initialtreatment, they may be eligible for second-line chemotherapy, provided theyhave an acceptable performance status.

We applaud Dr. Cappuzzo andcolleagues for an excellentreview of an emerging fieldin lung cancer treatment. Since 2000,three drugs (docetaxel [Taxotere],pemetrexed [Alimta], and erlotinib[Tarceva]) have been approved by theUS Food and Drug Administration(FDA) for second-line therapy in non–small-cell lung cancer (NSCLC) basedon the results of phase III trials (seeTable 1).[1-4] It is also possible thatsimilar approval will be sought for otherdrugs (eg, topotecan [Hycamtin]),[5]and gefitinib (Iressa) remains an optionfor treatment in the third-line setting.

ORLANDO - Combined immunochemotherapy results in superior remission rates and overall survival in recurrent follicular and mantle cell lymphoma, and providing rituximab (Rituxan) maintenance therapy prolongs duration of response, according to new findings presented by Martin Dreyling, MD, PhD, at the American Society of Clinical Oncology 41st Annual Meeting (abstract 6527 and abstract 6528). "Combined immunotherapy resulted in superior remission rates and survival rates," said Dr. Dreyling, of the University of Munich, Germany. "To the best of my knowledge, this is the first study that proves that on a solid base of data."

Platinum-based chemotherapy offers a modest survival advantage overbest supportive care in chemotherapy-naive patients with a good performancestatus and advanced/metastatic non–small-cell lung cancer(NSCLC). Despite the survival benefit associated with first-line chemotherapy,the majority of patients will experience relapse or disease progression.In clinical practice, an increasing number of patients maintaina good performance status after first-line treatment and are eligible forfurther treatments. Docetaxel (Taxotere) at 75 mg/m2 given once every3 weeks has been the standard of care for second-line chemotherapy sincethe year 2000. Pemetrexed (Alimta) is a novel multitargeted antifolateagent with single-agent activity in first- and second-line treatment ofNSCLC. A large phase III study comparing docetaxel to pemetrexed insecond-line therapy demonstrated that pemetrexed is equally active andless toxic than docetaxel. Based on these results, pemetrexed is a reasonablesecond-line chemotherapy option for patients with recurrent, advancedNSCLC. Progress made in the field of molecular biology has led to theidentification of drugs active against specific cellular targets. Gefitinib(Iressa) and erlotinib (Tarceva) are both orally active tyrosine kinase inhibitorsof the epidermal growth factor receptor. Phase II and III trialshave demonstrated that these agents are active particularly in a subgroupof patients with specific biologic characteristics. Both drugs have beenapproved for the treatment of pretreated NSCLC. Other drugs, such ascetuximab (Erbitux) and bevacizumab (Avastin) have shown promisingactivity in NSCLC and are currently being tested in clinical trials.

Cappuzzo and colleagues havereviewed the present optionsof salvage therapy for advancednon–small-cell lung cancer(NSCLC). This issue is highly relevantnowadays, as many patients whofail palliative chemotherapy are stillin sufficiently good condition to receiveadditional therapy. It is ratherinstructive to note that 10 years agothe use of systemic chemotherapy foradvanced NSCLC was advocated butstill not standard, and today we haveseveral options for treating patients inthe second- and even third-line setting.Among these options are agents thatspecifically target molecular featuresof lung cancer, such as the epidermalgrowth factor receptor (EGFR)

At this time there is no therapy that can restore vision after retinal ganglion cell (RGC) death in patients with glaucoma. However, stem cell-based treatments do have the potential to restore function in individuals with various neurodegenerative diseases, reported Keith R. Martin, MD, of Cambridge University, Cambridge, England, at the annual meeting of the Association for Research in Vision and Ophthalmology.

At this time there is no therapy that can restore vision after retinal ganglion cell (RGC) death in patients with glaucoma. However, stem cell-based treatments do have the potential to restore function in individuals with various neurodegenerative diseases, reported Keith R. Martin, MD, of Cambridge University, Cambridge, England, at the annual meeting of the Association for Research in Vision and Ophthalmology.

Squamous cell carcinomas of the head and neck are highly responsiveto induction chemotherapy. However, randomized trials have failedto demonstrate a survival advantage with the addition of induction chemotherapyto locoregional therapy consisting of surgery and/or radiationtherapy. Currently, concomitant radiation and chemotherapy hasemerged as a standard and has optimized locoregional control in headand neck cancer. In this setting, the addition of induction chemotherapymay further improve outcome by enhancing both locoregional and distantcontrol. As interest in induction regimens is renewed, we elected toconduct a systematic review of trials of induction chemotherapy forlocoregionally advanced head and neck cancer. The most studied combination-cisplatin plus fluorouracil (5-FU)-achieves objective responserates of about 80%. In a meta-analysis, induction with platinum/5-FU resulted in a small survival advantage over locoregionaltherapy alone. The introduction of a taxane into induction chemotherapyregimens has produced promising results. Induction chemotherapyshould be the subject of further clinical research in head andneck cancer. Randomized clinical trials in which the control arm isconcurrent chemoradiotherapy and the experimental arm is inductionchemotherapy followed by concurrent chemoradiotherapy are planned.Platinum/taxane combinations are the preferred regimens for furtherstudy in the induction setting and a suitable platform with which toinvestigate the addition of novel targeted agents.

The variability and complexity of central nervous system germ cell tumors have led to controversy in both diagnosis and management. If a germ cell tumor is suspected, the measurement of cerebrospinal fluid and serum alpha-fetoprotein and beta–human chorionic gonadotropin is essential. A histologic specimen is not necessary if the patient has elevated levels; however, if the tumor markers are negative, a biopsy is needed to confirm the diagnosis of a germinoma. Germinomas are extremelyradiosensitive, enabling 5-year survival rates that exceed 90%. Treatment has traditionally included focal and craniospinal axis irradiation; however, multiple ongoing studies are being conducted to examinethe efficacy of reduction or elimination of radiation therapy with the addition of chemotherapy. Nongerminomatous germ cell tumors, on the other hand, are relatively radioresistant with a poorer outcome. The combination of chemotherapy and irradiation is associated with overall survival rates of up to 60%. This article provides a review of the controversies in diagnosis and treatment of central nervous system germ cell tumors.

Standard therapy for multiple myeloma, which accounts for 10% ofall hematologic malignancies, has been autologous stem cell transplantation(ASCT), alkylator-based chemotherapy, and corticosteroids. Severaladvances have been made in the treatment of multiple myelomaover the past decade, especially the arrival of new, active agents suchas thalidomide (Thalomid), bortezomib (Velcade), and lenalidomide(Revlimid). These have shown significant clinical activity as singleagents. Trials are ongoing to incorporate these new agents into thevarious stages of treatment and to combine them with other effectivetreatment modalities, including ASCT.

Priming of leukemic cells with cytokines may enhance the efficacy of cell-cycle chemotherapy. In this study, we utilized these synergistic effects of granulocyte-macrophage colony-stimulating factor (GM-CSF, sargramostim [Leukine]), hydroxyurea, and low-dose cytosine arabinoside to treat elderly patients with acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS). In a single-institution, retrospective study, we evaluated 94 treatments with concomitant hydroxyurea, cytosine arabinoside, and GM-CSF between the years of 1997 and 2003 in high-risk elderly patients with AML or MDS. A total of 80% of patients received all of the GM-CSF doses; 78% of patients received all of the cytosine arabinoside doses. Adverse events were minimal. No patient developed mucositis or alopecia. The most common adverse event was neutropenic fever, which was noted in 57% of patients. Twenty-one percent of patients remained neutropenic after treatment until death or relapse. Sixty-eight percent of patients reached an absolute neutrophil count of greater than 1,000 μL in a median of 33.5 days. Our data show an overall response rate of 52%, with a complete response rate of 39% and a partial response rate of 13%. Overall, our study showed that low-dose cytosine arabinoside given by continuous infusion together with continuous infusion GM-CSF and hydroxyurea was well-tolerated and effective in treating elderly AML and MDS patients who were not eligible for standard induction therapy.

The most common subtype of aggressive non-Hodgkin’s lymphomais diffuse large B-cell lymphoma (DLBCL). Diffuse large B-cell lymphomarepresents a heterogeneous entity, with 5-year overall survivalrates ranging from 26% to 73%. Microarray gene expression studieshave confirmed that biologically distinct subgroups exist within DLBCL,and can be correlated with outcome. Initial management is usuallyguided by stage of disease at presentation. Approximately 25% of patientswith DLBCL present with limited-stage disease and are treatedwith combined-modality therapy (brief chemotherapy and involved-fieldradiation). Most patients present with advanced-stage disease and requiretreatment with an extended course of chemotherapy. The CHOP(cyclophosphamide, doxorubicin HCl, vincristine [Oncovin], prednisone)chemotherapy regimen has been the mainstay of therapy sinceits development in the 1970s, as more intensive chemotherapy regimensfailed to show additional benefit. The era of monoclonal antibodieshas transformed treatment practices for aggressive lymphoma andhas led to a significant improvement in outcome. A randomized trialcomparing the use of rituximab (Rituxan), a chimeric anti-CD20 IgG1monoclonal antibody, combined with CHOP chemotherapy vs CHOPchemotherapy alone for elderly patients with advanced-stage DLBCLdemonstrated a significant benefit for the combination approach. Thisfinding has now been confirmed in two additional randomized, controlledtrials and a population-based analysis, making CHOP andrituximab the standard of care for all newly diagnosed patients withDLBCL. Despite this advance, newer therapies are needed and manyare under active investigation. The insights gained from molecular techniquessuch as gene expression profiling should permit identificationof additional lymphoma-specific therapeutic targets and the developmentof novel agents that take into account underlying biology andallow for greater tailoring of therapy.

The most common indolent lymphoma, follicular lymphoma comprises 35% of adult non-Hodgkin’s lymphoma (NHL) in the United States and 22% worldwide. Features associated with adverse outcome include age, male gender, disease stage, and performance status, with the International Prognostic Index being the most widely used risk classification system. Long-term disease-free survival is possible in select patient subgroups after treatment, but very late relapses suggest that quiescent lymphoma cells might be harbored for long periods of time. Radiation therapy is the mainstay of treatment for limited-stage follicular lymphoma, but there is some experience with chemotherapy and combined chemoradiation. When to initiate treatment in patients with advanced disease is controversial, but options include various combined chemotherapy regimens, monoclonal antibodies, radiolabeled antibodies, and bone marrow or stem cell transplantation. Future directions in the treatment of follicular lymphoma include vaccines, antisense therapy, and proteasome inhibitors.

Vaccines are a promising but still experimental treatment for melanoma.They are intended to stimulate immune responses against melanomaand by so doing, increase resistance against and slow the progressionof this cancer. Key requirements for vaccines to be effectiveare that they contain antigens that can stimulate tumor-protective immuneresponses and that some of these antigens are present on thetumor to be treated. Unfortunately, these antigens are still not known.To circumvent this problem, polyvalent vaccines can be constructedcontaining a broad array of melanoma-associated antigens. Severalstrategies are available to construct such polyvalent vaccines; each hasadvantages and disadvantages. Clinical trials have shown that vaccinesare safe to use and have much less toxicity than current therapy formelanoma. Vaccines can stimulate both antibody and T-cell responsesagainst melanoma, with the type of response induced, its frequency,and its magnitude depending on the vaccine and the adjuvant agentused. A growing body of evidence suggests that vaccines can be clinicallyeffective. This evidence includes correlations between vaccineinducedantibody or T-cell responses and improved clinical outcome,clearance of melanoma markers from the circulation, improved survivalcompared to historical controls, and most convincingly, two randomizedtrials in which the recurrence-free survival of vaccine-treatedpatients was significantly longer than that of control groups.

Overexpression of cyclooxygenase-2 (COX-2) is frequently presentin lung cancer and may play a significant role in carcinogenesis, invasion,and metastasis. It has been associated with shortened survival inpatients with resected early-stage adenocarcinoma of the lung. COX-2inhibition decreases tumor cell proliferation in vivo and has been shownto enhance tumor radiosensitivity. Additionally, COX-2 inhibition mayprotect normal pulmonary tissue from radiation fibrosis. Clinical studiesare under way to assess the potential benefits and risks of COX-2inhibition in the treatment of lung cancer. The rationale for COX-2inhibitors in the treatment of lung cancer will be reviewed. The resultsof a phase II study assessing the acute toxicity of concurrent celecoxib(Celebrex) and thoracic irradiation in patients with non–small-cell lungcancer (NSCLC) are reported, and an ongoing Radiation TherapyOncology Group study using celecoxib and concurrent radiation therapyfor NSCLC in patients with intermediate prognostic factors is reviewed.

The epidermal growth factor receptor (EGFR) plays an importantrole in cell growth, differentiation, and survival. Targeting EGFR inpatients with colorectal cancer has become an important therapeutictool. Recently, a monoclonal antibody against the extracellular domainof the receptor (cetuximab [Erbitux]) has been approved for the treatmentof patients with EGFR-positive metastatic disease refractory toirinotecan (Camptosar)-based therapy. The role of other targeted agentsagainst EGFR, including other monoclonal antibodies as well as inhibitorsof the intracellular tyrosine kinase domain, will also be discussed.

Defects in the regulation of apoptosis (programmed cell death) makeimportant contributions to the pathogenesis and progression of mostcancers and leukemias. Apoptosis defects also figure prominently inresistance to chemotherapy, radiotherapy, hormonal therapy, andimmune-based treatments. Apoptosis is caused by activation ofintracellular proteases, known as caspases, that are responsible directlyor indirectly for the morphologic and biochemical events thatcharacterize the apoptotic cell. Numerous proteins that regulate thesecell death proteases have been discovered, including proteins belongingto the Bcl-2, inhibitor of apoptosis, caspase-associated recruitmentdomain, death domain, and death effector domain families. Thesecaspase-regulating proteins provide mechanisms for linkingenvironmental stimuli to cell death responses or to maintenance of cellsurvival. Alterations in the expression and function of several apoptosisregulatinggenes have been demonstrated in cancer, suggesting targetsfor drug discovery. Knowledge of the molecular details of apoptosisregulation and the three-dimensional structures of apoptosis proteinshas revealed new strategies for identifying small-molecule drugs thatmay yield more effective treatments for malignancies. Apoptosisregulatinggenes are also beginning to find utility as targets for antisenseoligonucleotides.

Although no overall differences in survival have been observed betweenthe many chemotherapy combinations in non–small-cell lungcancer, the clinical application of mRNA expression levels of amplifiedgenes may disclose many genetic influences on cytotoxic drug sensitivityand enable clinicians to tailor chemotherapy according to eachindividual’s gene profile. Specifically, the assessment of ribonucleotidereductase subunit M1 and thymidylate synthase mRNA expression levelsmight select patients who benefit from gemcitabine (Gemzar) orpemetrexed (Alimta) combinations. Until recently, clinical prognosticfactors such as performance status, weight loss, and lactate dehydrogenasewere the only parameters used to predict chemotherapy responseand survival. However, accumulated data indicate that overexpressionof genes involved in cancer glycolysis pathways plays an important role,and might be an independent mechanism of chemoresistance. Thedysregulation of glycolytic genes is affected by growth signals involvingthe PI3K/Akt pathway and downstream genes such as hypoxiainduciblefactor-1-alpha. One can thus envision that substantial improvementsin therapeutic outcome could benefit from the integrationof tailored ribonucleotide reductase-dependent chemotherapy, ribonucleotidereductase antisense therapy, and targeted therapy.

Candidiasis and aspergillosis are the most common fungal infectionsin hematopoietic stem cell transplant recipients and other hematology/oncology patients. Strategies for reducing the morbidity and mortalityassociated with these infections include antifungal prophylaxis,empiric therapy in patients with persistent fever and neutropenia, andpreemptive therapy. Antifungal therapies include amphotericin B deoxycholate,lipid formulations of amphotericin B, the triazoles (fluconazole,itraconazole, and voriconazole), and the echinocandins (caspofunginand the investigational agents micafungin and anidulafungin).Fluconazole is a reasonable choice for the treatment of invasive candidiasisif the patient has not previously received a triazole and theinstitution has a low incidence of triazole resistance. If resistance is aconcern, an echinocandin, such as caspofungin, is an appropriate option.Voriconazole may be the initial choice in most patients with invasiveaspergillosis. If patients are intolerant of or refractory to conventionaltherapy, effective alternatives include a lipid formulation of amphotericinB or an echinocandin.