Actinobacteria from Antarctica as a source for anticancer discovery

• Published in: Scientific reports Vol. 10; no. 1; p. 13870
• Main Authors: Silva, Leonardo Jose, Crevelin, Eduardo José, Souza, Danilo Tosta, Lacerda-Júnior, Gileno Vieira, de Oliveira, Valeria Maia, Ruiz, Ana Lucia Tasca Gois, Rosa, Luiz Henrique, Moraes, Luiz Alberto Beraldo, Melo, Itamar Soares
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17-08-2020; Nature Publishing Group
• Subjects: 631/154/1435/2163; 631/61; 631/61/514; Actinobacteria; Actinobacteria - metabolism; Actinomycetales - metabolism; Antarctic Regions; Anthracyclines - isolation & purification; Anthracyclines - metabolism; Anthracyclines - pharmacology; Antineoplastic Agents - isolation & purification; Antineoplastic Agents - metabolism; Antineoplastic Agents - pharmacology; Biological Factors - biosynthesis; Biological Factors - isolation & purification; Biological Factors - pharmacology; Breast; Cell culture; Cell Line, Tumor; Cell Proliferation - drug effects; Cinerubin; Cultivation techniques; Culture Techniques - methods; Dactinomycin - biosynthesis; Dactinomycin - isolation & purification; Dactinomycin - pharmacology; Drug Discovery; Endemic species; Glioblastoma; Humanities and Social Sciences; Humans; Metabolites; multidisciplinary; Natural products; Neoplasms - pathology; Public health; Reservoirs; Rhizosphere; rRNA 16S; Science; Science (multidisciplinary); Secondary metabolites; Streptomyces; Streptomyces - metabolism; Tumor cell lines; Tumors; Antarctic Regions
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69786-2

Although many advances have been achieved to treat aggressive tumours, cancer remains a leading cause of death and a public health problem worldwide. Among the main approaches for the discovery of new bioactive agents, the prospect of microbial secondary metabolites represents an effective source for the development of drug leads. In this study, we investigated the actinobacterial diversity associated with an endemic Antarctic species,
Deschampsia antarctica
, by integrated culture-dependent and culture-independent methods and acknowledged this niche as a reservoir of bioactive strains for the production of antitumour compounds. The 16S rRNA-based analysis showed the predominance of the Actinomycetales order, a well-known group of bioactive metabolite producers belonging to the Actinobacteria phylum. Cultivation techniques were applied, and 72 psychrotolerant Actinobacteria strains belonging to the genera
Actinoplanes
,
Arthrobacter
,
Kribbella
,
Mycobacterium
,
Nocardia
,
Pilimelia
,
Pseudarthrobacter
,
Rhodococcus
,
Streptacidiphilus
,
Streptomyces
and
Tsukamurella
were identified. The secondary metabolites were screened, and 17 isolates were identified as promising antitumour compound producers. However, the bio-guided assay showed a pronounced antiproliferative activity for the crude extracts of
Streptomyces
sp. CMAA 1527 and
Streptomyces
sp. CMAA 1653. The TGI and LC
50
values revealed the potential of these natural products to control the proliferation of breast (MCF-7), glioblastoma (U251), lung/non-small (NCI-H460) and kidney (786-0) human cancer cell lines. Cinerubin B and actinomycin V were the predominant compounds identified in
Streptomyces
sp. CMAA 1527 and
Streptomyces
sp. CMAA 1653, respectively. Our results suggest that the rhizosphere of
D. antarctica
represents a prominent reservoir of bioactive actinobacteria strains and reveals it as an important environment for potential antitumour agents.