Germ cell-specific heat shock protein 70-2 is expressed in cervical carcinoma and is involved in the growth, migration, and invasion of cervical cells.
BACKGROUND
Cervical cancer is a major cause of death among women worldwide, and the most cases are reported in the least developed countries. Recently, a study on DNA microarray gene expression analysis demonstrated the overexpression of heat shock protein 70-2 (HSP70-2) in cervical carcinoma cells (HeLa). The objective of the current study was to evaluate the association between HSP70-2 expression in cervical carcinogenesis and its potential role in various malignant properties that result in disease progression.


METHODS
HSP70-2 expression was examined in various cervical cancer cell lines with different origins and in clinical cervical cancer specimens by reverse transcriptase-polymerase chain reaction (RT-PCR), flow cytometry, and immunohistochemistry (IHC) analyses. A plasmid-based, short-hairpin RNA approach was used specifically to knock down the expression of HSP70-2 in cervical tumor cells in vitro and in vivo to examine the role of HSP70-2 on various malignant properties.


RESULTS
RT-PCR and IHC analyses revealed HSP70-2 expression in 86% of cervical cancer specimens. Furthermore, knockdown of HSP70-2 expression significantly reduced cellular growth, colony formation, migration, and invasion in vitro and reduced tumor growth in vivo. A significant association of HSP70-2 gene and protein expression was observed among the various tumor stages (P=.046) and different grades (P=.006), suggesting that HSP70-2 expression may be an indicator of disease progression.


CONCLUSIONS
The current findings suggested that HSP70-2 may play an important role in disease progression in cervical carcinogenesis. Patients who had early stage disease and low-grade tumors had HSP70-2 expression, supporting its potential role in early detection and aggressive treatment modalities for cervical cancer management.
Garg
Manoj
M
Cancer Microarray, Genes, and Proteins Laboratory, National Institute of Immunology, New Delhi, India.
Kanojia
Deepika
D
Saini
Shikha
S
Suri
Sushma
S
Gupta
Anju
A
Surolia
Avadhesha
A
Suri
Anil
A
D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D018450:Disease Progression; D005260:Female; D055785:Gene Knockdown Techniques; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness; D009368:Neoplasm Transplantation; D002583:Uterine Cervical Neoplasms / Q000378:metabolism* / Q000473:pathology*
D018840:HSP70 Heat-Shock Proteins; C525621:HSPA1B protein, human