SCCOHT tumors acquire chemoresistance and protection by interacting mesenchymal stroma/stem cells within the tumor microenvironment

Abstract

Chemotherapeutic drug testing of SCCOHT-1 and BIN-67 tumor cells revealed synergistic growth-inhibition of >95% in vitro with a combination of foretinib and FK228. Application of this drug combination in vivo in NODscid mice-induced SCCOHT-1GFP tumors was associated with ~6-fold reduction in tumor mass within 10 days, whereby synergistic effects of the two compounds remained undetectable compared to previous results with foretinib treatment alone. Histopathologic evaluation revealed a reduced vascularization and a lower amount of proliferating cells in the treated tumors. Surprisingly, a simultaneous significant accumulation of extracellular matrix structures with positive elastin-van Gieson staining was observed following foretinib/FK228 exposure. Expression analysis of treated animal tumors exhibited various changes including increased mouse transcript levels of elastin, laminin, and fibronectin. In parallel, markers for mesenchymal stroma/stem cells (MSC) including CD73 and CD90 were detectable in all mouse tumors suggesting a possible involvement of these cells in extracellular matrix restructure. Indeed, incubation of MSC with FK228 or foretinib/FK228 demonstrated morphologic alterations and enhanced expression of laminin and fibronectin. Moreover, a co-culture of MSC with lentiviral-labeled SCCOHT-1GFP cells contributed to protection of the tumor cells against FK228-mediated cytotoxicity. Furthermore, explant cultures of SCCOHT-1GFP-induced tumors acquired an increased resistance to FK228 and a combination of foretinib/FK228 in contrast to foretinib alone. Together, these data suggested that FK228-mediated extracellular matrix protein expression by MSC contributes to increased protection and enhanced resistance of SCCOHT tumors which could represent a more general mechanism of MSC during drug-induced alterations of a tumor microenvironment.

Enhanced metastatic capacity of breast cancer cells after interaction and hybrid formation with mesenchymal stroma/stem cells (MSC)

“…Although previous work suggested that tumor-associated aberrant MSC contribute to tumor cell protection either directly by expression of protective extracellular matrix proteins and/or indirectly by promoting a carcinoma stem cell niche [ 41 , 64 , 65 ], the involvement of MSC in MDA-hyb1 and MDA-hyb2 cell formation displays increased sensitivity to various chemotherapeutic compounds.…”

“…The cDNA reactions were performed for 10 min/25 °C, 1 h/37 °C and stopped at 72 °C for 10 min. As a template 2.5 μl of cDNA was used with primers specific for - mcherry (sense: 5`-TTC ATG TAC GGC TCC AAG GC-3′; antisense: 5`-CTG CTT GAT CTC GCC CTT CA-3′; amplification product 297 bp) - eGFP (sense: 5`-CTA TAT CAT GGC CGA CAA GCA GA-3′; antisense: 5`-GGA CTG GGT GCT CAG GTA GTG G-3′; amplification product 165 bp) - CD73 (sense: 5’-CGC AAC AAT GGC ACA ATT AC-3′; antisense: 5’-CTC GAC ACT TGG TGC AAA GA-3′; amplification product 241 bp) [ 9 ]; - CD90 (sense: 5′-GGA CTG AGA TCC CAG AAC CA-3′; antisense: 5’-ACG AAG GCT CTG GTC CAC TA-3′; amplification product 124 bp) [ 9 ]; - CD105 (sense: 5′-TGT CTC ACT TCA TGC CTC CAG CT-3′; antisense: 5′-AGG CTG TCC ATG TTG AGG CAG T-3′; amplification product 378 bp) [ 9 ] - MFSD-2A (sense: 5`-CTC CTG GCC ATC ATG CTC TC-3′; antisense: 5`-GGC CAC CAA GAT GAG AAA-3′; amplification product 129 bp) - syncytin-2 (sense: 5`-AGC AGC CGT AGT CCT TCA AA-3′; antisense: 5`-AGG GGA AGA ACC CAA GAG AA-3′; amplification product 231 bp) [ 39 ] - Ki67 (sense: 5`-TAT CAA AAG GAG CGG GGT CG-3′; antisense: 5`-TTG AGC TTT TCT CAT CAG GGT CA-3′; amplification product 389 bp) [ 40 ] - GAPDH as a control (sense: 5’-ACC ACA GTC CAT GCC ATC AC-3′; antisense: 5’-TCC ACC ACC CTG TTG CTG TA-3′; amplification product 452 bp) [ 41 ] (all primers customized by Eurofins, MWG GmbH, Ebersberg, Germany). PCR reactions included 0.2 μM of each primer, 200 μM of dNTP (R0193, Thermo Scientific) and 0.03 U One Taq Hot Start DNA polymerase (New England Biolabs GmbH, Frankfurt am Main, Germany) in the supplied reaction buffer.…”

“…- GAPDH as a control (sense: 5’-ACC ACA GTC CAT GCC ATC AC-3′; antisense: 5’-TCC ACC ACC CTG TTG CTG TA-3′; amplification product 452 bp) [ 41 ] (all primers customized by Eurofins, MWG GmbH, Ebersberg, Germany). PCR reactions included 0.2 μM of each primer, 200 μM of dNTP (R0193, Thermo Scientific) and 0.03 U One Taq Hot Start DNA polymerase (New England Biolabs GmbH, Frankfurt am Main, Germany) in the supplied reaction buffer.…”

MSC stimulate ovarian tumor growth during intercellular communication but reduce tumorigenicity after fusion with ovarian cancer cells

“…MSC-mediated chemoresistance of a drug combination was previously observed in the rare small cell ovarian carcinoma (SCCOHT) [ 36 ]. This “chemoresistance” was partially based on tumor-protective effects by enhanced CA-MSC-mediated filament expression including collagen, laminin, elastin, and fibronectin [ 37 ] which may explain similar effects in the filamentous tumor microenvironment of MSC co-cultured SK-OV-3 cells.…”

Breast Carcinoma: From Initial Tumor Cell Detachment to Settlement at Secondary Sites

“…Moreover, interactions between MSC and cancer cells proceed bidirectionally since vice versa, acquisition of some epithelial-like markers including epithelial cell adhesion molecule (EpCAM) can be detected in MSC following coculture with ovarian cancer cells [36]. Furthermore, MSC acquire increased expression of ECM proteins such as fibronectin and laminin during certain chemotherapeutic treatment and thereby promote tumor cell protection and a distinct chemoresistance [37]. …”