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Tölle M, Gökbuget N, Habringer S, Keller U, Schwartz S. Plasmapheresis effectively abrogates severe liver toxicity of pegaspargase in a patient with acute lymphoblastic leukemia. Ann Hematol 2024:10.1007/s00277-024-05789-7. [PMID: 38733396 DOI: 10.1007/s00277-024-05789-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024]
Affiliation(s)
- Markus Tölle
- Department of Nephrology and Medical Intensive Care (Campus Benjamin Franklin), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Nicola Gökbuget
- Medizinische Klinik II, Universitätsklinikum der Johann-Wolfgang-Goethe Universität, Theodor-Stern-Kai 7, 60596, Frankfurt/Main, Germany
- German Cancer Consortium (DKTK), partner site Frankfurt/Mainz, a partnership between DKFZ and Johann-Wolfgang-Goethe Universität, 60596, Frankfurt/Main, Germany
| | - Stefan Habringer
- Department of Hematology, Oncology and Cancer Immunology (Campus Benjamin Franklin), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
- German Cancer Consortium (DKTK), partner site Berlin, a partnership between DKFZ and Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Ulrich Keller
- Department of Hematology, Oncology and Cancer Immunology (Campus Benjamin Franklin), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
- German Cancer Consortium (DKTK), partner site Berlin, a partnership between DKFZ and Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Stefan Schwartz
- Department of Hematology, Oncology and Cancer Immunology (Campus Benjamin Franklin), Charité - Universitätsmedizin Berlin, corporate member of Freie Universität and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany.
- German Cancer Consortium (DKTK), partner site Berlin, a partnership between DKFZ and Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany.
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Chakraborty M, Shivakumar S. Application of sequential design for enhanced L-asparaginase synthesis from Ganoderma australe GPC191. World J Microbiol Biotechnol 2024; 40:85. [PMID: 38296867 DOI: 10.1007/s11274-023-03881-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Accepted: 12/26/2023] [Indexed: 02/02/2024]
Abstract
With an increasing demand for L-asparaginase in pharmaceutical and food sectors for its cytostatic and acrylamide-reducing qualities, there's a need to discover novel, highly productive enzyme sources with improved pharmacokinetic profiles. Keeping this in mind, the present study aimed at maximizing the potential of Ganoderma australe GPC191 to produce L-asparaginase by fermentation medium optimization using statistical validation. Of the 11 physicochemical parameters evaluated under submerged fermentation conditions through one-factor-at-a-time approach and Plackett-Burman design, only four parameters (inoculum load, L-asparagine, soybean meal, and initial pH) influenced L-asparaginase production, significantly (p < 0.001). The optimal levels and interaction effects of these on the overall production were further evaluated by the central composite rotatable design of response surface methodology. Post-optimization, 27.34 U/mL was predicted as the maximum activity at pH 7 with 5n inoculum load and 15 g/L each of L-asparagine and soybean meal. Experimental validation yielded an activity of 28.52 U/mL, indicating an overall 18.17-fold increase from the unoptimized stage. To our knowledge, this is the first report signifying the L-asparaginase production aptitude of G. australe with sequential statistical validation using agricultural waste, which can serve as a model to enhance its yields, offering a sustainable and cost-effective solution for industrial application.
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Affiliation(s)
- Meghna Chakraborty
- Department of Microbiology and Botany, School of Sciences, JAIN (Deemed-to-be University), Bangalore, Karnataka, 560027, India
| | - Srividya Shivakumar
- School of Allied Healthcare and Sciences (SAHS), JAIN (Deemed-to-be University), Bangalore, Karnataka, 560066, India.
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Darnal S, Raj R, Chhimwal J, Thakur S, Padwad YS, Singh D. Apoptosis and cell cycle arrest of leukemic cells by a robust and stable L-asparaginase from Pseudomonas sp. PCH199. Int J Biol Macromol 2024; 258:128739. [PMID: 38096943 DOI: 10.1016/j.ijbiomac.2023.128739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 11/07/2023] [Accepted: 12/09/2023] [Indexed: 12/23/2023]
Abstract
Biomolecules obtained from microorganisms living in extreme environments possess properties that have pharmacokinetic advantages. Enzyme assay revealed recombinant L-ASNase, an extremozyme from Pseudomonas sp. PCH199 is to be highly stable with 90 % activity (200 h) at 37 °C. The stability of the enzyme in human serum (50 % activity maintained in 63 h) reveals high therapeutic potential with less dosage. The enzyme exhibited cytotoxicity to K562 blood cancer cell lines with IC50 of 0.37 U/mL without affecting the IEC-6 normal epithelial cell line. Due to the depletion of L-asparagine, K562 cells experience nutritional stress that results in the abruption of metabolic processes and eventually leads to apoptosis. Comparative studies on MCF-7 cells also revealed the same fate. Due to nutritional stress induced by L-ASNase treatment, mitochondrial membrane potential was lost, and reactive oxygen species were increased to 48 % (K562) and 21 % (MCF-7) as indicated by flow cytometric analysis. DAPI staining with prominent nuclear morphological changes visualized under the fluorescent microscope confirmed apoptosis in both cancer cells. Treatment increases pro-apoptotic Bax protein, and eventually, the cell cycle is arrested at the G2/M phase in both cell lines. Therefore, the current study paves the way for PCH199 L-ASNase to be considered a potential chemotherapeutic agent for treating acute lymphoblastic leukemia.
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Affiliation(s)
- Sanyukta Darnal
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, India
| | - Ravi Raj
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, India
| | - Jyoti Chhimwal
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, India; Dietetics & Nutrition Technology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India
| | - Shubham Thakur
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India
| | - Yogendra S Padwad
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, India; Dietetics & Nutrition Technology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India.
| | - Dharam Singh
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh 176 061, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, India.
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4
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Cassaday RD. Asparaginase dosing for obese patients with acute lymphoblastic leukemia and factors that contribute to outcomes. Best Pract Res Clin Haematol 2023; 36:101519. [PMID: 38092476 DOI: 10.1016/j.beha.2023.101519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Asparaginase in various forms is a standard part of the treatment of acute lymphoblastic leukemia (ALL) in children and adolescents. However, its use is more selective in adults. One of the key reasons is the toxicity observed from this class of agents. In a series of recent post hoc analyses of large prospective studies, obesity has emerged as a key factor that contributes to the challenges with administering regimens that include asparaginase. In this review, the most salient findings are highlighted from these latest publications, both from the pediatric and adult literature. These data are consolidated into recommendations for clinicians who treat adults with ALL, including proposals for how treatment may be modified to try to account for these complications. Lastly, avenues for future investigation are proposed in an attempt to narrow our knowledge gaps in this field, with the goal of safer and more effective treatment for adults with obesity who develop ALL.
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Affiliation(s)
- Ryan D Cassaday
- Department of Medicine, University of Washington, Seattle, WA, USA; Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA.
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Bassan R, Chiaretti S, Della Starza I, Spinelli O, Santoro A, Paoloni F, Messina M, Elia L, De Propris MS, Scattolin AM, Audisio E, Marbello L, Borlenghi E, Zappasodi P, Mauro E, Martinelli G, Mattei D, Fracchiolla N, Bocchia M, De Fabritiis P, Bonifacio M, Candoni A, Cassibba V, Di Bartolomeo P, Latte G, Trappolini S, Guarini A, Vitale A, Fazi P, Piciocchi A, Rambaldi A, Foà R. Pegaspargase-modified risk-oriented program for adult acute lymphoblastic leukemia: results of the GIMEMA LAL1913 trial. Blood Adv 2023; 7:4448-4461. [PMID: 37276451 PMCID: PMC10440455 DOI: 10.1182/bloodadvances.2022009596] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/17/2023] [Accepted: 05/21/2023] [Indexed: 06/07/2023] Open
Abstract
Pediatric-inspired chemotherapy is the standard of care for younger adults with Philadelphia chromosome-negative acute lymphoblastic leukemia/lymphoma (Ph- ALL/LL). In LAL1913 trial, the Gruppo Italiano Malattie EMatologiche dell'Adulto added pegaspargase 2000 IU/m2 to courses 1, 2, 5, and 6 of an 8-block protocol for patients aged from 18 to 65 years, with dose reductions in patients aged >55 years. Responders were risk stratified for allogeneic hematopoietic cell transplantation (HCT) or maintenance per clinical characteristics and minimal residual disease (MRD). Of 203 study patients (median age, 39.8 years), 91% achieved a complete remission. The 3-year overall survival, event-free, and disease-free survival (DFS) rates were 66.7%, 57.7%, and 63.3%, respectively, fulfilling the primary study end point of a 2-year DFS >55%. Although based on the intention-to-treat, the DFS being 74% and 50% in the chemotherapy (n = 94) and HCT (n = 91) assignment cohorts, respectively, a time-dependent analysis proved the value of HCT in patients who were eligible (DFS HCT 70% vs no HCT 26%; P <.0001). In multivariate analysis, age and MRD were independent factors predicting DFS rates of 86% (age ≤ 40 and MRD-negative), 64%-65% (MRD-positive or age > 40) and 25% (age > 40 and MRD-positive); P < .0001. Grade ≥2 pegaspargase toxicity was mainly observed at course 1, contributing to induction death in 2 patients but was rare thereafter. This program improved outcomes of patients with Ph- ALL/LL aged up to 65 years in a multicenter national setting. This trial was registered at www.clinicaltrials.gov as #NCT02067143.
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Affiliation(s)
- Renato Bassan
- Complex Operational Unit of Hematology, Ospedale dell'Angelo, Mestre-Venezia, Italy
| | - Sabina Chiaretti
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
| | - Irene Della Starza
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
- Centro Dati Fondazione GIMEMA Franco Mandelli, Rome, Italy
| | - Orietta Spinelli
- Complex Structure of Hematology, AO Papa Giovanni XXIII, Bergamo; and Department of Oncology and Hematology, University of Milan, Milan, Italy
| | - Alessandra Santoro
- Division of Hematology, Ospedali Riuniti Villa Sofia-Cervello, Palermo, Italy
| | | | - Monica Messina
- Centro Dati Fondazione GIMEMA Franco Mandelli, Rome, Italy
| | - Loredana Elia
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
| | - Maria Stefania De Propris
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
| | - Anna Maria Scattolin
- Complex Operational Unit of Hematology, Ospedale dell'Angelo, Mestre-Venezia, Italy
| | - Ernesta Audisio
- Complex Structure of Hematology, AO Città della Salute e della Scienza, Torino, Italy
| | - Laura Marbello
- Complex Structure of Hematology, Ospedale Niguarda Ca’ Granda, Milan, Italy
| | - Erika Borlenghi
- Operational Unit of Hematology, AO Spedali Civili, Brescia, Italy
| | - Patrizia Zappasodi
- Complex Structure of Hematology, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Elisa Mauro
- Complex Operational Unit of Hematology, AOU Policlinico S. Marco, University of Catania, Catania, Italy
| | - Giovanni Martinelli
- Institute of Hematology "Seragnoli", Policlinico S. Orsola-Malpighi, University of Bologna, Bologna, Italy
| | - Daniele Mattei
- Complex Structure of Hematology, ASO S. Croce e Carle, Cuneo, Italy
| | - Nicola Fracchiolla
- Complex Operational Unit of Onco-Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore, Milan, Italy
| | - Monica Bocchia
- Complex Operational Unit of Hematology, AO Senese Policlinico Le Scotte, Siena, Italy
| | - Paolo De Fabritiis
- Complex Operational Unit of Hematology, Ospedale S. Eugenio ASL Roma 2, University of Tor Vergata, Rome, Italy
| | - Massimiliano Bonifacio
- Department of Medicine, Complex Operational Unit of Hematology, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Anna Candoni
- Department of Hematology, Azienda Ospedaliero-Universitaria, Udine, Italy
| | | | | | - Giancarlo Latte
- Section of Clinical Hematology, Ospedale S. Francesco, Nuoro, Italy
| | | | - Anna Guarini
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
| | - Antonella Vitale
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
| | - Paola Fazi
- Centro Dati Fondazione GIMEMA Franco Mandelli, Rome, Italy
| | | | - Alessandro Rambaldi
- Complex Structure of Hematology, AO Papa Giovanni XXIII, Bergamo; and Department of Oncology and Hematology, University of Milan, Milan, Italy
| | - Robin Foà
- Division of Hematology, Department of Cellular Biotechnologies and Hematology, "Sapienza" University of Rome, Rome, Italy
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Blachier J, Cleret A, Guerin N, Gil C, Fanjat JM, Tavernier F, Vidault L, Gallix F, Rama N, Rossignol R, Piedrahita D, Andrivon A, Châlons-Cottavoz M, Aguera K, Gay F, Horand F, Laperrousaz B. L-asparaginase anti-tumor activity in pancreatic cancer is dependent on its glutaminase activity and resistance is mediated by glutamine synthetase. Exp Cell Res 2023; 426:113568. [PMID: 36967104 DOI: 10.1016/j.yexcr.2023.113568] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/13/2023] [Accepted: 03/21/2023] [Indexed: 03/31/2023]
Abstract
l-Asparaginase is a cornerstone of acute lymphoblastic leukemia (ALL) therapy since lymphoblasts lack asparagine synthetase (ASNS) and rely on extracellular asparagine availability for survival. Resistance mechanisms are associated with increased ASNS expression in ALL. However, the association between ASNS and l-Asparaginase efficacy in solid tumors remains unclear, thus limiting clinical development. Interestingly, l-Asparaginase also has a glutaminase co-activity that is crucial in pancreatic cancer where KRAS mutations activate glutamine metabolism. By developing l-Asparaginase-resistant pancreatic cancer cells and using OMICS approaches, we identified glutamine synthetase (GS) as a marker of resistance to l-Asparaginase. GS is the only enzyme able to synthesize glutamine, and its expression also correlates with l-Asparaginase efficacy in 27 human cell lines from 11 cancer indications. Finally, we further demonstrated that GS inhibition prevents cancer cell adaptation to l-Asparaginase-induced glutamine starvation. These findings could pave the way to the development of promising drug combinations to overcome l-Asparaginase resistance.
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Mudd TW, Fox AD, Ghaly M, Keruakous A. Case report: Hyperosmolar hyperglycemic syndrome secondary to PEG-asparaginase-induced hypertriglyceridemia and pancreatitis. Front Oncol 2023; 12:1094964. [PMID: 36741726 PMCID: PMC9893891 DOI: 10.3389/fonc.2022.1094964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 12/23/2022] [Indexed: 01/21/2023] Open
Abstract
Pegylated (PEG)-asparaginase is an established treatment for acute lymphoblastic leukemias that exhibits an antitumor effect by depleting asparagine, an amino acid essential for leukemia cell protein synthesis. Pancreatitis with hypertriglyceridemia is a well-established toxidrome associated with PEG-asparaginase. However, impaired pancreatic synthetic function and hormone release have rarely been reported as a result of PEG-asparaginase pancreatitis. In this report, we present a 22-year-old woman recently diagnosed with T-acute lymphoblastic leukemia (T-ALL), who presented to the hospital with progressive weakness, confusion, blurry vision, hallucinations, and abdominal pain after induction treatment with daunorubicin, vincristine, PEG-asparaginase, and dexamethasone following the AYA protocol. She was found to have hypertriglyceridemia, acute pancreatitis, and hyperosmolar hyperglycemic syndrome. While pancreatitis and hypertriglyceridemia are commonly reported side effects of PEG-asparaginase, HHS related to these conditions has been sparsely reported. Providers should maintain awareness of this association and consider routine serial glucose monitoring of patients receiving PEG-asparaginase.
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Affiliation(s)
| | - Ashley Danielle Fox
- Department of Internal Medicine, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Mark Ghaly
- Georgia Southern University, Savannah, GA, United States
| | - Amany Keruakous
- Department of Hematology and Oncology, Georgia Cancer Center, Augusta, GA, United States,*Correspondence: Amany Keruakous,
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Alqahtani A, Alhousari D, Ali A, Yaghmour G, Orgel E, Curran E, Stock W, Bhojwani D, Alachkar H. Asparaginase toxicity in Hispanic adult and pediatric patients with acute lymphoblastic leukemia: current understanding. Expert Opin Drug Metab Toxicol 2023; 19:357-366. [PMID: 37410014 DOI: 10.1080/17425255.2023.2233412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 07/03/2023] [Indexed: 07/07/2023]
Abstract
INTRODUCTION Asparaginase is essential to chemotherapy regimens for acute lymphoblastic leukemia (ALL). Survival of patients with ALL has improved since incorporating asparaginase into chemotherapy backbones. Hispanic patients have a higher incidence of ALL than other ethnicities and suffer inferior outcomes. The inferior outcome of Hispanics is due to several factors, including the increased incidence of high-risk genetic subtypes and susceptibility to treatment-related toxicity. AREAS COVERED We summarize the current knowledge of asparaginase-related toxicity by comparing their incidence between Hispanic and non-Hispanic patients. These toxicities include hypersensitivity, hepatotoxicity, pancreatitis, thrombosis, and hypertriglyceridemia. The PubMed database and Google Scholar were used to search for this review from October 2022 to June 2023. EXPERT OPINION Except for hepatotoxicity and hypertriglyceridemia secondary to asparaginase-based treatments, which may develop more frequently among Hispanic patients with ALL, other toxicities were comparable between Hispanic and non-Hispanic patients. Nevertheless, studies with larger cohorts and more accurate capturing of Hispanic ethnicity should be conducted to fill the gaps in the current knowledge.
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Affiliation(s)
- Amani Alqahtani
- School of Pharmacy, University of Southern California, Los Angeles, CA, USA
- Department of Clinical Pharmacy, School of Pharmacy, Najran University, Najran, Saudi Arabia
| | - Diala Alhousari
- School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Amir Ali
- USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
| | - George Yaghmour
- USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
| | - Etan Orgel
- USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
- Cancer and Blood Disease Institute, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Emily Curran
- The Department of Medicine, Section of Hematology & Oncology at the University of Cincinnati College of Medicine
| | - Wendy Stock
- Section of Hematology/Oncology, Department of Medicine, University of Chicago, Chicago, IL, USA
| | - Deepa Bhojwani
- USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
- Cancer and Blood Disease Institute, Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | - Houda Alachkar
- School of Pharmacy, University of Southern California, Los Angeles, CA, USA
- USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
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Yanti NA. Phenotypic Characterization and Identification of Potential L-Asparaginase-Producing Thermohalophilic Bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi, Indonesia. Pak J Biol Sci 2022; 25:1021-1032. [PMID: 36591934 DOI: 10.3923/pjbs.2022.1021.1032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
<b>Background and Objective:</b> L-asparaginase-producing thermohalophilic bacteria have the potential of producing an enzyme tolerant to high heat and salt levels. This enzyme, L-asparaginase, can be used as a biological agent for the cancer therapy of acute lymphoblastic leukemia and melanosarcoma as it has a specific ability to inhibit the formation of nutrients for cancer cells. This enzyme is also used effectively in food industries operating at high temperatures due to its ability to reduce acrylamide, a trigger of cancer cells. This study sought to figure out the phenotypic characters of and identify potential L-asparaginase-producing thermohalophilic bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi. <b>Materials and Methods:</b> The characterization conducted on potential L-asparaginase-producing thermohalophilic bacterial isolates consisted of the following: Colony morphological characterization, covering the shapes, edges, internal structures, elevations and colours of the colonies, cell morphological characterization, covering gram staining, endospore formation and motility, biochemical characterization, covering catalase, Methyl Red and Voges Proskauer (MR-VP), gelatin hydrolysis, citrate, indole and carbohydrate fermentation tests and physiological characterization, covering pH effect, salinity, oxygen demand and temperature effect tests. Bacterial isolate identification was carried out in two stages, namely phenetic identification based on the phenotypic characterization data determine through a preliminary identification and numeric-phenetic identification. <b>Results:</b> The characterization results showed that the bacterial isolates AAT 1.4, AAT 3.2 and CAT 3.4 were <i>bacillus</i>-shaped, Gram-positive, motile, catalase-positive and aerobic. Based on the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 had a 92.9% similarity to <i>Bacillus subtilis</i>, while isolate AAT 3.2 had a 92.9% similarity to <i>Brevibacillus limnophilus</i>. <b>Conclusion:</b> According to the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 belong to the species <i>Bacillus subtilis</i>, while isolate AAT 3.2 belongs to the species <i>Brevibacillus limnophilus</i>.
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