Alpha-CaMKII Plays a Critical Role in Determining the Aggressive Behavior of Human Osteosarcoma

Abstract

Osteosarcoma is among the most frequently occurring primary bone tumors, primarily affecting adolescents and young adults. Despite improvements in osteosarcoma treatment, more specific molecular targets are needed as potential therapeutic options. One target of interest is alpha-Ca2+/calmodulin-dependent protein kinase II (α-CaMKII), a ubiquitous mediator of Ca2+-linked signaling, which has been shown to regulate tumor cell proliferation and differentiation. Here, we investigate the role of α-CaMKII in the growth and tumorigenicity of human osteosarcoma. We show that α-CaMKII is highly expressed in primary osteosarcoma tissue derived from 114 patients and is expressed in varying levels in different human osteosarcoma cell lines (HOS, MG-63, MNNG/HOS and 143B). To examine whether α-CaMKII regulates osteosarcoma tumorigenic properties, we genetically inhibited α-CaMKII in two osteosarcoma cell lines using two different α-CaMKII shRNAs delivered by lentiviral vectors and overexpressed α-CaMKII by retrovirus. The genetic deletion of α-CaMKII by shRNA in MG-63 and 143B cells resulted in decreased proliferation (50 and 41%), migration (22 and 25%) and invasion (95 and 90%), respectively. The overexpression of α-CaMKII in HOS cells resulted in increased proliferation (240%), migration (640%) and invasion (10,000%). Furthermore, α-CaMKII deletion in MG-63 cells significantly reduced tumor burden in vivo (65%), while α-CaMKII overexpression resulted in tumor formation in a previously non-tumor forming osteosarcoma cell line (HOS). Our results suggest that α-CaMKII plays a critical role in determining the aggressive phenotype of osteosarcoma, and its inhibition could be an attractive therapeutic target to combat this devastating adolescent disease.

Phosphorylation of calcium/calmodulin-stimulated protein kinase II at T286 enhances invasion and migration of human breast cancer cells

“…As we and others have previously shown111622, overexpression of WT CaMKII significantly increases cell proliferation, when compared to EV control cells, as measured by Cell Titer Blue (Fig. 3A,B) and clonogenic assays (Fig.…”

“…Recent studies have demonstrated that CaMKII is involved in controlling osteosarcoma and gastric cancer cell invasion and migration1622, and lung cancer tumourigenicity29, and we have previously implicated CaMKII in breast cancer cell proliferation1130. However, the role of CaMKII phosphorylation in cancer cell invasion and migration has not previously been explored.…”

Estrogen Activation of CaM Kinases and Transcription Is Blocked by Vitamin D in MCF-7 Breast Cancer Cells

“…The role for the different isoforms of CaM Kinases in oncogenesis is rapidly emerging and evidence supports the involvement for CaM KK, CaM KI, CaM KIV, CaM KII as well as their various substrates and cellular targets in cancer development [60,[68][69][70][71][72][73][74]. Consistent with our data, Iglewski et al demonstrated that urotensin treatment of primary smooth muscle cells activated a CaM KK/CaM KI/ERK proliferation pathway although the ability of other hormones to inhibit this process was not examined [75].…”

Control of cell mechanics by RhoA and calcium fluxes during epithelial scattering

“…Overexpression of a-CaMKII in several osteosarcoma cell lines results in an increase in migration, proliferation, and a dramatic increase in invasion, all hallmarks of EMT, while knockdown results in a significant reduction in these behaviors. 83 CaMKID, a homolog of CaMKII, is overexpressed in invasive carcinomas and leads to EMT, increased cell proliferation, loss of cellcell adhesions, and increases migration and invasion. 84 In prostate cancer cells, the non-canonical Wnt5a calcium pathway was shown to be important in wound closure and cell migration; inhibition of CaMKII with AIP prevents wound closure in scratched confluent sheets and decreases cell motility in the same cell lines.…”