Purpose
HtrA1
,
HtrA2
,
HtrA3
and
HtrA4
appear to be involved in the development of pathologies such as cancer. This systematic review reports the results of a literature search performed to compare the expression of HtrA family genes and proteins in cancer versus non-cancer tissues and cell lines, assess relationships between HtrA expression and cancer clinical features in cancer, and analyse the molecular mechanism, by which HtrA family affects cancer.
Methods
The literature search was conducted according to the PRISMA statement among four databases (PubMed, Web of Science, Embase and Scopus).
Results
A total of 38 articles met the inclusion criteria and involved the expression of HtrA family members and concerned the effect of HtrA expression on cancer and metastasis development or on the factor that influences it. Additionally, 31 reports were retrieved manually. Most articles highlighted that
HtrA1
and
HtrA3
exhibited tumour suppressor activity, while
HtrA2
was associated with tumour growth and metastasis. There were too few studies to clearly define the role of the
HtrA4
protease in tumours.
Conclusion
Although the expression of serine proteases of the HtrA family was dependent on tumour type, stage and the presence of metastases, most articles indicated that
HtrA1
and
HtrA3
expression in tumours was downregulated compared with healthy tissue or cell lines. The expression of
HtrA2
was completely study dependent. The limited number of studies on
HtrA4
expression made it impossible to draw conclusions about differences in expression between healthy and tumour tissue. The conclusions drawn from the study suggest that
HtrA1
and
HtrA3
act as tumour suppressors.
Supplementary Information
The online version contains supplementary material available at 10.1007/s40291-024-00712-2.