Malignant myoepithelial cells are associated with the differentiated papillary structure and metastatic ability of a syngeneic murine mammary adenocarcinoma model

Table 1 Summary of cytological, histological and immunocytochemical features of LM38 sublines growing in monolayer culture, in suspension, or after subcutaneous inoculation in vivo

Feature	LM38-LP	LM38-HP	LM38-D2
Monolayer cultures
Islets of epithelioid cells	Abundant	Absent	Absent
Pan-CK	+++
Vimentin	+/-
α-SMA	-
E-cadherin	+
Small spindle cells	Scarce	Abundant	Absent
Pan-CK	Not defined	++
Vimentin	Not defined	+
α-SMA	-	-
E-cadherin	-	-
Large spindle cells	Abundant	Scarce	Abundant^a
Pan-CK	+	+	+
Vimentin	+/-	+/-	ND
α-SMA	+++	+/++	+++
E-cadherin	-	-	-
Spheroids	Yes	Yes	ND
Shape	Smooth, round	Irregular clusters
Morphogenesis	Gland-like	Loose and solid cords
Pan-CK	+++ polarized cells	++ intermingled cells
α-SMA/CK14	+++ central, peripheral or isolated cells	+ intermingled cells
Subcutaneous tumors	Papillary differentiated adenocarcinoma	Poorly differentiated adenocarcinoma	Undifferentiated (myoepithelioma-like)
Pan-CK	+++ abundant cells	+ or +/- scarce cells	ND
α-SMA	+++ abundant cells	+/- scarce cells	+++

^aPure cell type. α-SMA, α-smooth muscle actin; CK14 = cytokeratin 14; ND, not done; pan-CK, pancytokeratins.

ISSN: 1465-542X