Repurposing propranolol as a drug for the treatment of retinal haemangioblastomas in von Hippel-Lindau disease

β-Adrenoreceptors as Therapeutic Targets for Ocular Tumors and Other Eye Diseases-Historical Aspects and Nowadays Understanding

β-adrenoreceptors (ARs) are members of the superfamily of G-protein-coupled receptors (GPCRs), and are activated by catecholamines, such as epinephrine and norepinephrine. Three subtypes of β-ARs (β₁, β₂, and β₃) have been identified with different distributions among ocular tissues. Importantly, β-ARs are an established target in the treatment of glaucoma. Moreover, β-adrenergic signaling has been associated with the development and progression of various tumor types. Hence, β-ARs are a potential therapeutic target for ocular neoplasms, such as ocular hemangioma and uveal melanoma. This review aims to discuss the expression and function of individual β-AR subtypes in ocular structures, as well as their role in the treatment of ocular diseases, including ocular tumors.

Propranolol: A “Pick and Roll” Team Player in Benign Tumors and Cancer Therapies

Research on cancer therapies focuses on processes such as angiogenesis, cell signaling, stemness, metastasis, and drug resistance and inflammation, all of which are influenced by the cellular and molecular microenvironment of the tumor. Different strategies, such as antibodies, small chemicals, hormones, cytokines, and, recently, gene editing techniques, have been tested to reduce the malignancy and generate a harmful microenvironment for the tumor. Few therapeutic agents have shown benefits when administered alone, but a few more have demonstrated clear improvement when administered in combination with other therapeutic molecules. In 2008 (and for the first time in the clinic), the therapeutic benefits of the β-adrenergic receptor antagonist, propranolol, were described in benign tumors, such as infantile hemangioma. Propranolol, initially prescribed for high blood pressure, irregular heart rate, essential tremor, and anxiety, has shown, in the last decade, increasing evidence of its antitumoral properties in more than a dozen different types of cancer. Moreover, the use of propranolol in combination therapies with other drugs has shown synergistic antitumor effects. This review highlights the clinical trials in which propranolol is taking part as adjuvant therapy at single administration or in combinatorial human trials, arising as a good pick and roll partner in anticancer strategies.

The Role of Propranolol as a Repurposed Drug in Rare Vascular Diseases

Rare Diseases (RD) are defined by their prevalence in less than 5 in 10,000 of the general population. Considered individually, each RD may seem insignificant, but together they add up to more than 7000 different diseases. Research in RD is not attractive for pharmaceutical companies since it is unlikely to recover development costs for medicines aimed to small numbers of patients. Since most of these diseases are life threatening, this fact underscores the urgent need for treatments. Drug repurposing consists of identifying new uses for approved drugs outside the scope of the original medical indication. It is an alternative option in drug development and represents a viable and risk-managed strategy to develop for RDs. In 2008, the “off label” therapeutic benefits of propranolol were described in the benign tumor Infantile Hemangioma. Propranolol, initially prescribed for high blood pressure, irregular heart rate, essential tremor, and anxiety, has, in the last decade, shown increasing evidence of its antiangiogenic, pro-apoptotic, vasoconstrictor and anti-inflammatory properties in different RDs, including vascular or oncological pathologies. This review highlights the finished and ongoing trials in which propranolol has arisen as a good repurposing drug for improving the health condition in RDs.

Efficacy and safety of current treatment options for peripheral retinal haemangioblastomas: a systematic review

IMPORTANCE

Approximately twenty per cent of Von Hippel-Lindau patients with retinal haemangioblastomas (RH) suffer from visual impairment. Various treatment options are available for peripheral RH. However, management of peripheral RH is complex due to multifocality and bilaterality.

OBJECTIVE

To summarize published evidence on efficacy and safety of different interventions for peripheral RH and to provide treatment recommendations for specialists.

EVIDENCE REVIEW

Comprehensive searches were performed using Medline, Embase, Web of Science and Google Scholar database on 4 March 2020. English publications that described outcomes related to efficacy or complications in at least two patients with peripheral RH were included. Efficacy and safety were estimated by complete tumour eradication rate, pretherapeutic and treatment-related complication rate. Odds ratios (OR) with 95% confidence intervals (CI) were calculated to calculate the risk estimate of complications between treatment options.

FINDINGS

Twenty-seven articles were included in this review describing nine different treatment options for peripheral RH: laser photocoagulation (n = 230), cryotherapy (n = 50), plaque radiotherapy (n = 27), vitreoretinal surgery (n = 88), photodynamic therapy (PDT; n = 14), transpupillary thermotherapy (TTT; n = 10), external beam radiotherapy (n = 3), systemic treatment (n = 7) and intravitreal anti-VEGF (n = 2). Complete tumour eradication was achieved in 86.7% (95% CI: 83.5-89.9%) of all eyes. For the different treatments, this was after laser photocoagulation 89.9% (86.1-93.7%), cryotherapy 70.2% (57.0-83.4%), plaque radiotherapy 96.3% (89.1-100.0%), vitreoretinal surgery (100.0%), PDT 64.3% (38.3-90.3%) and TTT 80.0% (53.8-100.0%). No complete tumour eradication was achieved after systemic therapy, external beam radiotherapy or intravitreal anti-VEGF. Photodynamic therapy and vitreoretinal surgery showed the highest complication rate after treatment compared to the other treatments (OR 10.5 [95% CI: 2.9-38.4]) and (OR 5.9 [95% CI: 3.4-9.9]), respectively. Cases that had pretherapeutic complications showed a higher treatment-related complication rate (OR 14.8 [95% CI: 7.3-30.0]) than cases without complications before treatment.

CONCLUSIONS AND RELEVANCE

These findings suggest that laser photocoagulation is the safest and most effective treatment method for peripheral RH up to 1.5 mm in diameter. Vitreoretinal surgery has the highest success rate for complete tumour eradication and may be the most suitable treatment option in the presence of pretherapeutic complications and for larger tumours.

Blockade of β2-Adrenergic Receptor Reduces Inflammation and Oxidative Stress in Clear Cell Renal Cell Carcinoma

Von Hippel-Lindau (VHL) syndrome is a rare inherited cancer disease where the lack of VHL protein triggers the development of multisystemic tumors such us retinal hemangioblastomas (HBs), CNS-HBs, and clear cell renal cell carcinoma (ccRCC). Since standard therapies in VHL have shown limited response, leaving surgery as the only possible treatment, targeting of the β2-adrenergic receptor (ADRB2) has shown therapeutic antitumor benefits on VHL-retinal HBs (clinical trial), VHL-CNS HBs, and VHL-ccRCC (in vitro and in vivo). In the present study, we wanted to look deep into the effects of the ADRB2 blockers propranolol and ICI-118,551 on two main aspects of cancer progression: (i) the changes on the inflammatory response of ccRCC cells; and (ii) the modulation on the Warburg effect (glycolytic metabolism), concretely, on the expression of genes involved in the cell reactive oxygen species (ROS) balance and levels. Accordingly, in vitro studies with primary VHL-ccRCC and 786-O cells measuring ROS levels, ROS-expression of detoxifying enzymes, and the expression of p65/NF-κB targets by RT-PCR were carried out. Furthermore, histological analyses of ccRCC samples from heterotopic mouse xenografts were performed. The obtained results show that ADRB2 blockade in ccRCC cells reduces the level of oxidative stress and stabilizes the inflammatory response. Thus, these data further support the idea of targeting ADRB2 as a promising strategy for the treatment of VHL and other non-VHL tumors.

The Endothelial Landscape and Its Role in Von Hippel-Lindau Disease

Von Hippel–Lindau disease (VHL) is a rare hereditary disease characterized by the predisposal to develop different types of highly vascularized tumors. VHL patients carry a VHL mutation that causes partial lack of functional VHL protein (pVHL) in all cells, and a total lack thereof in cells harboring a second hit mutation. Absence of pVHL generates a prolonged state of pseudo-hypoxia in the cell due to accumulation of hypoxia inducible factor, an important transcription factor regulating pro-tumorigenic genes. The work here presented focuses on characterizing the endothelium of VHL patients, by means of blood outgrowth endothelial cells (BOECs). Transcriptome analysis of VHL-derived BOECs, further supported by in vitro assays, shows that these cells are at a disadvantage, as evidenced by loss of cell adhesion capacity, angiogenesis defects, and immune response and oxidative metabolic gene downregulation, which induce oxidative stress. These results suggest that the endothelium of VHL patients is functionally compromised and more susceptible to tumor development. These findings contribute to shedding light on the vascular landscape of VHL patients preceding the second hit mutation in the VHL gene. This knowledge could be useful in searching for new therapies for these patients and other vascular diseases.

[Retinal tumors in adults - Part 1: vascular tumors of the retina]

Retinal tumors are a heterogeneous group of congenital and acquired lesions. In this review series the important retinal tumors are discussed and presented in two articles. In the first part of the article the most important vascular tumors of the retina are presented. Even with benign tumors visual symptoms, such as exudative retinal detachment occur, which often lead to irreversible visual impairments. Because visual symptoms are often a manifestation of systemic diseases, the ophthalmologist plays an important role in the accurate and early diagnosis of retinal tumors. This article reviews the most important clinical and diagnostic features of retinal vascular tumors in adults, their systemic associations and the literature on currently available treatment strategies.

Ophthalmological Aspects of von-Hippel-Lindau Syndrome

Background: von Hippel-Lindau (VHL) syndrome is a multisystem neoplastic disorder involving eyes, central nervous system, kidneys, spine, and other tissues. A retinal capillary hemangioma (RCH) is the earliest manifestation of the VHL disease in most cases.Areas covered:This paper aims to provide an up-to-date review of the current literature about von Hippel-Lindau syndrome. Molecular background, systemic and ocular features of the diseases as well as the utility of newer imaging modalities in diagnosis and monitoring of ocular VHL disease have been described. Besides, we have discussed newer treatment modalities and therapeutic targets.Conclusion: Modern imaging technologies like optical coherence tomography and optical coherence tomography angiography are tools of the trade, in making an appropriate diagnosis and monitoring disease activity and response to treatment. Peripheral RCH may be treated using laser photocoagulation in tumors up to 3000 µm. Vascular endothelial growth factor suppression can help in reducing tumor activity and stabilize the tumor size; however, it does not regress the RCH.

The endolymphatic sac tumor: challenges in the eradication of a localized disease

OBJECTIVE

Identify the critical points that lead to recurrences and lack of radicality in endolymphatic sac tumors (ELSTs).

STUDY DESIGN

Retrospective case study and review of the literature.

SETTING

Tertiary referral center.

PATIENTS

Thirteen cases of ELST were included in the study and their preoperative, intraoperative and postoperative data were analyzed and compared to a review of the literature.

INTERVENTION(S)

Therapeutical.

MAIN OUTCOME MEASURE(S)

Prevalence of recurrent and residual tumors, comparison to the literature and analysis of ELST characteristics.

RESULTS

Diagnosis was made 26 ± 17 months after the onset of symptomatology, and an ELST was preoperatively suspected in only six cases. At the time of surgery, 10 patients suffered from hearing loss. Preoperative symptoms or audiometry could not predict labyrinth infiltration, although speech discrimination scores were significantly associated with labyrinth infiltration (p = 0.0413). The labyrinth was infiltrated in 8 cases (57.1%), and in 7 cases (46.7%) the tumor eroded the carotid canal, whereas 6 cases (40%) presented an intradural extension. A gross total resection was achieved in 11 cases. There were two residual tumors, one of which because of profuse bleeding, and one recurrence (23.1%). A mean of 22.8% of recurrent or residual tumors are described in the literature based on 242 published cases, in more than half of the cases as a consequence of subtotal tumor resection (STR).

CONCLUSIONS

Recurrence derives mostly from the difficulty to identify the extension of the tumor due to the extensive bone infiltration. Accurate diagnosis and correct preoperative planning, with embolization when possible, will facilitate surgery and avoid STR due to intraoperative bleeding. Long follow-ups are important in order to avoid insidious recurrences.

Targeting β2-Adrenergic Receptors Shows Therapeutical Benefits in Clear Cell Renal Cell Carcinoma from Von Hippel-Lindau Disease

Von Hippel–Lindau (VHL), is a rare autosomal dominant inherited cancer in which the lack of VHL protein triggers the development of multisystemic tumors such us retinal hemangioblastomas (HB), CNS-HB, and clear cell renal cell carcinoma (ccRCC). ccRCC ranks third in terms of incidence and first in cause of death. Standard systemic therapies for VHL-ccRCC have shown limited response, with recurrent surgeries being the only effective treatment. Targeting of β2-adrenergic receptor (ADRB) has shown therapeutic antitumor benefits on VHL-retinal HB (clinical trial) and VHL-CNS HB (in vitro). Therefore, the in vitro and in vivo antitumor benefits of propranolol (ADRB-1,2 antagonist) and ICI-118,551 (ADRB-2 antagonist) on VHL^−/− ccRCC primary cultures and 786-O tumor cell lines have been addressed. Propranolol and ICI-118,551 activated apoptosis inhibited gene and protein expression of HIF-2α, CAIX, and VEGF, and impaired partially the nuclear internalization of HIF-2α and NFĸB/p65. Moreover, propranolol and ICI-118,551 reduced tumor growth on two in vivo xenografts. Finally, ccRCC patients receiving propranolol as off-label treatment have shown a positive therapeutic response for two years on average. In summary, propranolol and ICI-118,551 have shown antitumor benefits in VHL-derived ccRCC, and since ccRCCs comprise 63% of the total RCCs, targeting ADRB2 becomes a promising drug for VHL and other non-VHL tumors.

Von Hippel-Lindau Disease: Current Challenges and Future Prospects

Understanding of molecular mechanisms of tumor growth has an increasing impact on the development of diagnostics and targeted therapy of human neoplasia. In this review, we summarize the current knowledge on molecular mechanisms and their clinical implications in von Hippel-Lindau (VHL) disease. This autosomal dominant tumor syndrome usually manifests in young adulthood and predisposes affected patients to the development of benign and malignant tumors of different organ systems mainly including the nervous system and internal organs. A consequent screening and timely preventive treatment of lesions are crucial for patients affected by VHL disease. Surgical indications and treatment have been evaluated and optimized over many years. In the last decade, pharmacological therapies have been evolving, but are largely still at an experimental stage. Effective pharmacological therapy as well as detection of biomarkers is based on the understanding of the molecular basis of disease. The molecular basis of von Hippel-Lindau disease is the loss of function of the VHL protein and subsequent accumulation of hypoxia-inducible factor with downstream effects on cellular metabolism and differentiation. Organs affected by VHL disease may develop frank tumors. More characteristically, however, they reveal multiple separate microscopic foci of neoplastic cell proliferation. The exact mechanisms of tumorigenesis in VHL disease are, however, still not entirely understood and knowledge on biomarkers and targeted therapy is scarce.

β-blockers: Their new life from hypertension to cancer and migraine

The pharmacological class of β-blockers includes a plea of molecules with largely different pharmacokinetic and pharmacodynamic characteristics with a protective effect that may span far beyond the cardiovascular system. Although all these compounds share the pharmacological blockade of the adrenergic receptors, each of them is characterized by specific pharmacological properties, including selectivity of action depending on the adrenergic receptors subtypes, intrinsic sympathomimetic activity (ISA), lipid solubility, pharmacokinetic profile, and also other ancillary properties that impact their clinical effect. Their use in the treatment of hypertension has been extensively debated and at the moment a class indication is not present. However, in specific niche of patients, such as in those young individuals in which hypertension is mainly driven by a sympathetic hyperactivation, strong evidence pose β-Blockers as a highly reasonable first-line treatment. Lipophilic β-blockers, specifically propranolol and metoprolol, can cross the Blood Brain Barrier and have a Class A indication for the prophylactic treatment of migraine attacks. Moreover, since β-adrenergic receptors affect the proliferative process of both cancer and immune cells, their blockade has been associated with metastasis reduction in several epithelial and solid organ tumors posing β-Blockers as a new attractive, inexpensive and relatively safe therapeutic strategy in patients with several types of cancer. However, further dedicated prospective, randomized, placebo-controlled studies are needed to determine the real efficacy of these compounds.

The β2-adrenergic receptor antagonist ICI-118,551 blocks the constitutively activated HIF signalling in hemangioblastomas from von Hippel-Lindau disease

One of the major consequences of the lack of a functional VHL protein in von Hippel-Lindau disease, a rare cancer, is the constitutive activation of the HIF pathway. This activation ends up in the generation of Central Nervous System (CNS) Hemangioblastomas among other tumours along the lifespan of the patient. Nowadays, only surgery has been proven efficient as therapy since the systemic attempts have failed. Propranolol, a non-specific β1-and β2-adrenergic receptor antagonist, was recently designated as the first therapeutic (orphan) drug for VHL disease. Nevertheless, its β1 affinity provokes the decrease in blood pressure, being not recommended for low or regular blood pressure VHL patients. In order to overcome the β1-drawback, the properties of a high specific β2-adrenergic receptor blocker named ICI-118,551 have been studied. ICI-118,551 was able to decrease Hemangioblastomas cell viability in a specific manner, by triggering apoptosis. Moreover, ICI-118,551 also impaired the nuclear internalization of HIF-1α in Hemangioblastomas and hypoxic primary endothelial cells, reducing significantly the activation of HIF-target genes and halting the tumour-related angiogenic processes. In this work, we demonstrate the therapeutical properties of ICI-118,551 in VHL-derived CNS-Hemangioblastoma primary cultures, becoming a promising drug for VHL disease and other HIF-related diseases.

Evaluation of the safety and effectiveness of oral propranolol in patients with von Hippel-Lindau disease and retinal hemangioblastomas: phase III clinical trial

Background

von Hippel-Lindau disease (VHL) is a multisystem cancer syndrome caused by mutations in the VHL gene. Retinal hemangioblastoma is one of the most common tumours, and when it appears near the optic nerve, its treatment is challenging and risky. To date, no treatment has proven effective in changing the course of the disease. This study was designed to evaluate the safety and effectiveness of propranolol in controlling these tumours.

Methods

Seven patients were included. All patients took a daily dose of 120 mg of propranolol for 1 year. Clinical variables were assessed at baseline, and at 1, 3, 6, 9 and 12 months. The primary endpoint of the study was the number and size of retinal hemangioblastomas. On every visit, retinal outcomes and blood biomarkers (such as vascular endothelial growth factor (VEGF) and miR210) were analysed.

Results

Number and size of retinal hemangioblastomas remained stable in all patients. All of them had initially increased levels of VEGF and miR210. There was a gradual reabsorption of retinal exudation in two patients, correlating with a progressive decrease of both biomarkers. The only adverse effect reported was hypotension in one patient.

Conclusions

Propranolol could be used to treat retinal hemangioblastomas in VHL patients, although more studies are needed to determine the ideal dose and long-term effect. VEGF and miR210 should be explored as biomarkers of disease activity. As far as we know, these are the first biomarkers proposed to monitor the VHL disease activity.

Trial registration number

2014-003671-30.

Repurposing propranolol as an antitumor agent in von Hippel-Lindau disease

OBJECTIVE

Von Hippel-Lindau disease (VHL) is a tumor predisposition syndrome characterized by CNS hemangioblastomas (HBs) and clear cell renal cell carcinomas (RCCs) due to hypoxia-inducible factor activation (pseudohypoxia). Because of the lack of effective medical therapies for VHL, HBs and RCCs account for significant morbidity and mortality, ultimately necessitating numerous neurological and renal surgeries. Propranolol is an FDA-approved pan-beta adrenergic antagonist with antitumor effects against infantile hemangiomas (IHs) and possibly VHL HBs. Here, the authors investigated the antitumor efficacy of propranolol against pseudohypoxia-driven VHL-HBs and VHL-RCCs.

METHODS

Patient-derived VHL-associated HBs (VHL-HBs) or 786-O-VHL-/- RCC cells were treated with clinically relevant concentrations of propranolol in vitro and assessed with viability assays, flow cytometry, quantitative real-time polymerase chain reaction, and western blotting. In vivo confirmation of propranolol antitumor activity was confirmed in athymic nude mice bearing 786-O xenograft tumors. Lastly, patients enrolled in a VHL natural history study (NCT00005902) were analyzed for incidental propranolol intake. Propranolol activity against VHL-HBs was assessed retrospectively with volumetric HB growth kinetic analysis.

RESULTS

Propranolol decreased HB and RCC viability in vitro with IC50 (half maximal inhibitory concentration) values of 50 µM and 200 µM, respectively. Similar to prior reports in infantile hemangiomas, propranolol induced apoptosis and paradoxically increased VEGF-A mRNA expression in patient-derived VHL-HBs and 786-O cells. While intracellular VEGF protein levels were not affected by propranolol treatment, propranolol decreased HIF expression in 786-O cells (7.6-fold reduction, p < 0.005). Propranolol attenuated tumor progression compared with control (33% volume reduction at 7 days, p < 0.005) in 786-O xenografted tumor-bearing mice. Three patients (harboring 25 growing CNS HBs) started propranolol therapy during the longitudinal VHL-HB study. HBs in these patients tended to grow slower (median growth rate 27.1 mm3/year vs 13.3 mm3/year) during propranolol treatment (p < 0.0004).

CONCLUSIONS

Propranolol decreases VHL-HB and VHL-related RCC viability in vitro likely by modulation of VEGF expression and by inducing apoptosis. Propranolol abrogates 786-O xenograft tumor progression in vivo, and retrospective clinical data suggest that propranolol curtails HB growth. These results suggest that propranolol may play a role in the treatment of VHL-related tumors.

Regression of primary cardiac angiosarcoma and metastatic nodules following propranolol as a single agent treatment

Angiosarcoma is the most common malignant cardiac tumor. Cardiac angiosarcoma is a highly lethal neoplasm that is largely resistant to conventional anti-cancer therapy. Mean survival of patients with cardiac angiosarcoma is only 4 months, and almost all patients will succumb to the disease within 1 year. The beta blocker propranolol is an emerging therapy against angiosarcoma. When combined with conventional therapies, propranolol increases progression free and overall survival in patients with this tumor type. It is currently unknown if propranolol is capable of showing anti-cancer efficacy as a single agent therapy. We report a case of a 61 year old woman diagnosed with primary cardiac angiosarcoma and liver and lung metastases. This patient chose to decline conventional therapy, and instead was prescribed the beta blocker propranolol as a single agent treatment. After 12 months, the mediastinal mass substantially debulked and decreased in size, and the metastatic nodules stabilized or resolved with no evidence of hyper-metabolic activity on PET-CT. This is the first reported data showing long term efficacy of the beta blocker propranolol as a single agent therapy against angiosarcoma.

Propranolol and breast cancer-a work in progress

The non-selective beta-blocker propranolol is a leading candidate for repurposing as a novel anti-cancer agent. Emerging evidence, including human data, suggests that there are multiple mechanisms of action particularly relevant to breast cancer. This editorial reviews a number of recent studies that show it has anti-metastatic activity that warrants clinical investigation, including investigation as a potential perioperative therapy in breast cancer.

Adrenergic Signaling: A Targetable Checkpoint Limiting Development of the Antitumor Immune Response

An immune response must be tightly controlled so that it will be commensurate with the level of response needed to protect the organism without damaging normal tissue. The roles of cytokines and chemokines in orchestrating these processes are well known, but although stress has long been thought to also affect immune responses, the underlying mechanisms were not as well understood. Recently, the role of nerves and, specifically, the sympathetic nervous system, in regulating immune responses is being revealed. Generally, an acute stress response is beneficial but chronic stress is detrimental because it suppresses the activities of effector immune cells while increasing the activities of immunosuppressive cells. In this review, we first discuss the underlying biology of adrenergic signaling in cells of both the innate and adaptive immune system. We then focus on the effects of chronic adrenergic stress in promoting tumor growth, giving examples of effects on tumor cells and immune cells, explaining the methods commonly used to induce stress in preclinical mouse models. We highlight how this relates to our observations that mandated housing conditions impose baseline chronic stress on mouse models, which is sufficient to cause chronic immunosuppression. This problem is not commonly recognized, but it has been shown to impact conclusions of several studies of mouse physiology and mouse models of disease. Moreover, the fact that preclinical mouse models are chronically immunosuppressed has critical ramifications for analysis of any experiments with an immune component. Our group has found that reducing adrenergic stress by housing mice at thermoneutrality or treating mice housed at cooler temperatures with β-blockers reverses immunosuppression and significantly improves responses to checkpoint inhibitor immunotherapy. These observations are clinically relevant because there are numerous retrospective epidemiological studies concluding that cancer patients who were taking β-blockers have better outcomes. Clinical trials testing whether β-blockers can be repurposed to improve the efficacy of traditional and immunotherapies in patients are on the horizon.

Case Report: Propranolol increases the therapeutic response to temozolomide in a patient with metastatic paraganglioma

This case report presents the clinical evolution and management of a patient with a hereditary paraganglioma syndrome. This disease is characterized by rare tumors of neural crest origin that are symmetrically distributed along the paravertebral axis from the base of the skull and neck to the pelvis. In addition, these patients may develop renal cancer, gastrointestinal stromal tumors, pituitary adenomas, and bone metastasis in some cases. To date no successful therapeutic treatment has been reported. Total resection with postoperative radiotherapy and chemotherapy have been advocated, especially for the multiple metastasis. Here we show how the combination of high doses of the beta blocker propranolol (3 mg/Kg/day) and the DNA intercalating agent, temozolomide, has been successful in the treatment of a SDHA metastatic paraganglioma.