A new study recently published in the journal PLoS One revealed a new prognostic marker and potential new therapeutic target for cervical cancer. The study entitled “Synaptonemal Complex Protein 3 Is a Prognostic Marker in Cervical Cancer” was led by researchers at Korea University and Yonsei University College of Medicine in Republic of Korea.
Cervical cancer is characterized by an abnormal cell growth in the cervix, the lower part of the uterus. This cancer can be successfully treated when detected at an early stage, usually through a Papanicolaou (Pap) smear test, where the doctor scrapes a small sample of cervical cells to look for abnormal cell changes. It is estimated that in 2015, 12,900 new cases of cervical cancer will be diagnosed in the United States resulting in 4,100 deaths.
Tumor cells usually have an abnormal expression pattern of cancer/testis-associated antigens (CTAs) that makes them a valuable target for immunotherapeutic strategies. The role played by CTA expression in tumor cells remains, however, unclear. Members of the Cor1 family are typical CTAs, including the synaptonemal complex protein 3 (SCP3). In normal tissues, SCP3 is strictly expressed in the testis and ovaries; however SCP3 expression is also often detected in several human cancer cells, including cervical cancer. The oncogenic potential of SCP3 and its clinical significance still remain to be determined.
In the study, researchers analyzed the role of SCP3 in tumorigenesis. The protein was either overexpressed or knockdown in a non-tumorigenic murine cell line and several human cervical cancer cell lines. SCP3 expression was also analyzed in tumor samples from 181 cervical cancer patients and from 400 patients with cervical intraepithelial neoplasia (CIN, a potentially pre-malignant condition). The possible relation between SCP3 expression and survival or clinic-pathological features was also assessed.
Researchers found that SCP3 overexpression promoted tumorigenesis both in vitro and in vivo through the activation of AKT, a protein which is associated with tumor cell survival, proliferation and invasiveness. SCP3 expression was found to be associated with the tumor stage and grade, where SCP3 protein expression increases according to the severity of cervical lesions. This finding led the team to propose that SCP3 expression can be considered a prognostic factor for patients with cervical cancer. The survival rate for cervical cancer patients overexpressing both SCP3 and AKT was found to be significantly shorter than for patients with low SCP3 or AKT expression (median of 134 months vs 161.5 months). SCP3 expression was also found to be positively associated with AKT expression in both cervical cancer and CIN samples.
The research team concluded that SCP3 plays a key role in human tumorigenesis and in cervical cancer progression via the AKT signaling pathway. The team believes that SCP3 can be a promising prognostic marker and a novel therapeutic target for cervical cancer.