PC cell-derived growth factor is a novel
growth factor for
tumor formation and progression. No comprehensive literature concerning
PC cell-derived growth factor expression status and its
biological function in
squamous cell carcinoma, especially in the larynx, is, however, available. The target of this study is to evaluate the clinical significance of
PC cell-derived growth factor and the potential of
small interfering RNA-induced genetic silencing of
PC cell-derived growth factor as a supplementary therapeutic way for
laryngeal squamous cell carcinoma. A total of 146 primary
laryngeal cancer, 108 adult laryngeal
papilloma and 41 laryngeal
leukoplakia samples, as well as 10 normal larynx tissues were investigated. The
PC cell-derived growth factor mRNA level was examined by real-time polymerase chain reaction and
protein localization by immunohistochemistry. The
biological function of
PC cell-derived growth factor was assessed by transfection of
small interfering RNA PC cell-derived growth factor construction. The
PC cell-derived growth factor protein levels and
mRNA levels of the laryngeal
squamous cell carcinomas were significantly higher than those of normal laryngeal tissues (P<0.001). Simultaneously, the difference in the levels of
mRNA and
protein between those of laryngeal precancerous lesions (
papilloma/
leukoplakia) and those of normal tissues was significant (P<0.05, P<0.05), whereas those of laryngeal precancerous lesions (
papilloma/
leukoplakia) were significantly lower than those of laryngeal
squamous cell carcinomas (P<0.05, P<0.05). Strong
PC cell-derived growth factor expression was associated with
lymph node metastases in
laryngeal squamous cell carcinoma (P<0.05). Functional studies on Hep-2 cell lines demonstrated that the attenuation of
PC cell-derived growth factor expression levels led to diminished cell proliferation rates (P<0.001), anchorage-independent growth in vitro (P<0.001),
tumor forming in vivo (P<0.01) and resistance to apoptosis (P<0.001).
PC cell-derived growth factor is a pivotal autocrine
growth factor in the
tumorigenesis of
laryngeal squamous cell carcinoma. Our findings also indicate that
PC cell-derived growth factor is a logical and potential target for early diagnosis, specific
therapy and prognosis of
laryngeal squamous cell carcinoma.