Background: Matrix' metalloproteinases (MMPs) have
been implicated in the progression of tumors and specifically
in extracellular matrix degradation and remodelling. MMP-
19 differs from the others by its unique chromosomal location
(12q14). It also lacks several structural features known to be
present in other MMPs subclasses.
Objectives: To investigate the distribution patterns of
MMP-19 in cutaneous squamous cell carcinoma (SCC) as
well as expression of the cytokine (TNF-a) and keratinocyte
proliferative capacity, using anti-Ki-67 antibody.
Material and Methods: Nineteen SCC skin specimens
and Five normal skin controls were formalin-fixed, paraffinembedded
and stained immunohistochemically with anti-
MMP-19, TNF-a and Ki-67 monoclonal antibodies. The
standard Sterpt avidin biotin and APAAP methods were
applied.
Results: MMP-19 was absent in normal skin epidermis.
In SCC, positive expression was seen in well-differentiated
tumors and absent in poorly differentiated ones. Its distribution
pattern was mainly central in contrast to highly proliferating
invasive front. TNF-a was positive in apoptotic bodies and
malignant nests.
Conclusion: In contrary to other MMPs. MMP-19 does
not correlate to invasive and metastatic potential in cutaneous
SCC. It rather plays an indirect "protective" role. Its expression
in well differentiated SCC and absence in moderate and poorly
differentiated SCC, suggests its upregulation in the epidermis
early during oncogenesis in a host-response manner to reconstitute
normal cell adhesion |
