KLK5 is associated with the radioresistance, aggression, and progression of cervical cancer

OBJECTIVE

The role of kallikrein-related peptidase 5 (KLK5) has been studied in several diseases, including skin and ovarian cancers. However, its role in cervical cancer remains unclear, particularly in regulating the radiation resistance and growth of cervical cancer cells. Radiation resistance of cervical cancer is associated with local recurrence, distant metastasis, and reduced survival.

METHODS

We first analyzed radiotherapy-naive samples and relevant clinical data from patients with cervical cancer who received radiotherapy without surgery or other antitumor treatment from 2014 to 2016. Subsequently, biopsied tissues, in vitro cells, and transplanted tumors in nude mice were investigated.

RESULTS

Gene sequencing and clinical data analysis showed that KLK5 overexpression was associated with a poor prognosis post-radiotherapy. In in vitro cell and tumor transplantation experiments, KLK5 overexpression significantly increased radiation resistance. However, downregulating KLK5 expression increased radiosensitivity.

CONCLUSION

Our results confirm that KLK5 is vital to the radioresistance of cervical cancer, and provide a new target and marker for the treatment of radioresistance in cervical cancer.

Decreased shedding dipeptidyl peptidase 4 from membrane in Hashimoto's thyroiditis

AIMS

This study aimed to determine the concentration and enzymatic activity of dipeptidyl peptidase 4 (DPP4) in serum and peripheral blood mononuclear cells (PBMCs) from patients with Hashimoto's thyroiditis (HT) and to explore the potential mechanism of the abnormal DPP4 in HT development.

METHODS

A total of 33 newly diagnosed HT patients and 31 age- and sex-matched healthy controls were enrolled. Clinical characteristics and thyroid function data were collected for all participants. Serum DPP4 and kallikrein-related peptidase 5 (KLK5) concentrations were measured by sandwich enzyme-linked immunosorbent assay. DPP4 enzymatic activities in serum and PBMCs were determined by enzymatic assay. DPP4, KLK5 and interferon (IFN)-γ mRNA expression levels in PBMCs were evaluated by quantitative real-time polymerase chain reaction.

RESULTS

Serum DPP4 level and activity were significantly lower in the HT group compared with the control group. However, DPP4 mRNA expression was significantly increased and both serum KLK5 concentration and KLK5 mRNA expression in PBMCs were significantly decreased in HT patients. Correlation analyses revealed that DPP4 concentration was positively correlated with DPP4 enzymatic activity in serum. No significant difference in DPP4 activity was found in PBMCs. DPP4 enzymatic activity in PBMCs was negatively correlated with DPP4 enzymatic activity in serum. IFN-γ mRNA expression in PBMCs was significantly increased in HT patients.

CONCLUSIONS

DPP4 is involved in the development and pathological process of HT. Decreased cleavage of membrane-anchored DPP4 by KLK5 may be responsible for the decreased serum DPP4 levels in HT patients.