Influence of type 2 diabetes on immunohistochemical detection of TRAF6, cFos and NFATC1 in the gingiva in cases of chronic periodontitis

Type 2 diabetes (T2D) and chronic periodontitis (CP) are common diseases worldwide. Although T2D increases the severity of CP and alveolar bone loss, the mechanism of this is not well understood. We investigated using immunohistochemistry the expression of three osteoclast proteins, TRAF6, cFos and NFATc1, in gingival tissues. Gingival tissues were obtained from three groups: HC group, healthy controls; CP group, patients with CP; T2D + CP group, patients with both T2D and CP. Strong immunostaining for TRAF6, cFos and NFATc1 was observed in the gingival epithelium as well as in inflammatory cells in the CP and T2D + CP groups. Immunostaining was most intense in the T2D + CP group. We found strong up-regulation of TRAF6, cFos and NFATC1 in gingiva tissue of subjects with both T2D and CP, which corroborates our hypothesis that T2D potentiates osteoclastogenesis in CP.

Anti-carcinogenic Effect of Cathepsin K Inhibitor, Odanacatib with a Low Dose of Cisplatin Against Human Breast Carcinoma MCF-7 and MDA-MB231 Cells

Background:

A cross-linking agent commonly used for cancer chemotherapy is a platinum compound such as cisplatin. However, with the acquisition of cellular drug resistance and adverse side effects, the potency of cisplatin is, therefore, often tempered. To overcome these issues, the present study has established the use of cathepsin k (CTSK) inhibitor as a potent chemosensitizer.

Methods:

The cytotoxic effect of cisplatin and odanacatib (ODN) on two different breast cancer patient- derived cell lines, MDA-MB-231 and MCF-7, was assessed by MTT-based colorimetric assay. The drug interaction coefficient CDI was used to evaluate the synergistically inhibitory impact of the drug combination and immunoblot was used to examine the expression of certain proteins responsible for cell survival and the mechanism of apoptosis.

Results:

In this study, we found that IC50 of ODN in combination with cisplatin (half of IC25) induced a synergistic cytotoxic effect in different breast cancer cells. Diminished expression of Bcl-2 and increased expression of Bax aroused the cytochrome release, that triggered caspase-9 and -3 activation in the combinatorial group. ODN with a lower dose of cisplatin significantly inhibited the protein expression of novel chemoresistant factors such as STAT3, NFκB and IL-6.

Conclusion:

This study highlights the potential effects of the combination of ODN with a reduced dose of cisplatin on improving the growth inhibition and apoptosis-inducing effect on breast cancer cells via combined inhibition of NF-κB-induced IL-6 and STAT3 activation. The study result suggests that the further development of this novel inhibitor in combination with a low dose of standard cisplatin-based chemotherapy may contribute to an alternative treatment option for certain cancers.

Inhibitory Effects of Cathepsin K Inhibitor (ODN-MK-0822) on the Paracrine Pro-Osteoclast Factors of Breast Cancer Cells

BACKGROUND

Breast cancer (BC) produces bone resorptive cytokines and growth factors which accelerate the development of osteoclasts (OCs), leading to osteolytic bone metastases. In the Long-term Odanacatib Fracture Trial (LOFT), the skeletal-metastasized breast cancer subjects who received odanacatib (ODN) had a delayed tumour progression and skeletal tumour burden as a result of anti-resorptive effects through inhibition of cathepsin K (CTSK). In this study, we explored the effect of ODN, a CTSK inhibitor, on the paracrine pro-osteoclast activity of breast cancer cells.

METHODS

Immunohistochemistry study was performed to demonstrate CTSK and PTHrP expression in the samples of primary breast carcinoma. Expression of CTSK mRNA and protein was confirmed by the reverse transcription PCR and western blotting analysis in two human breast cancer cell lines MDA-MB-231 and MCF-7 BC cell lines. Cells were incubated with sub-lethal amounts of ODN, and their conditioned supernatants were assessed for their capacity to differentiate PBMCs of healthy donors into osteoclast and its interference on bone resorbing activities. We also measured the mRNA levels of major pro-osteoclast (pro-OC) factors in ODN-treated breast cancer cells and their secreted levels by semi-quantitative reverse transcription PCR and protein expression by immunoblotting.

RESULTS

Different staining intensity was observed in samples containing PTHrP and CTSK in various histological grades of breast carcinoma. Significant positive relationship was found between CTSK expression and histological grade of BC and presence or absence of distant metastasis.The present study results also indicate that ODN has no effects on OCs number , however; ODN decreases the mRNA expression of secreted pro-OC factors such as PTHrP, CXCR-4, and TNFα. Immuno blot indicates that ODN treatment decreased the protein expression of CTSK, IL-6, and IL-1β, and thus lowered protein levels paralleled the defective phosphorylation of NF-κB. Moreover, there was a significant reduction in the level of growth factors such as IGF-1, PDGF and TGFβ expression at transcriptional level after ODN treatment as compared to control.

CONCLUSION

ODN has shown to prevent osteolytic metastasis by interacting with the NF-κB pathway; inhibiting bone resorptive cytokines, and growth factors. This effect can also be take into account the delayed development of metastatic bone disease found in the long-term odanacatib fracture trial (LOFT) study.

Analysis of short-term variation and long-term drift during reagent kit lot change in an NABL accredited clinical biochemistry laboratory

BACKGROUND

Kit lot change in clinical biochemistry labs leads to variations in patient results. This study planned to identify variations during 60 reagent lot changes in our laboratory during the period from June 2018 to May 2019.

METHODS

A statistical analysis was performed to identify the difference between patient samples results variations and QC results. The long term drift was analyzed using a regression test.

RESULTS

There was a significant difference between the patient and QC results in 16.7% of reagent lot changes. Moreover, the extent of variation in QC results was 3.3%. No long-term drift was seen in three analytes which were studied using regression analysis.

CONCLUSIONS

Our results showed that, during reagent kit lot change, along with QC material, the patient samples should also be run in order to identify the variation. However, this practice is presently ignored by most of the laboratories. There was no accumulated effect in our laboratory due to reagent kit lot change.

Inhibitory effect of cathepsin K inhibitor (ODN-MK-0822) on invasion, migration and adhesion of human breast cancer cells in vitro

Approximately 90% of patients with advanced breast cancer develop bone metastases; an event that results in severe decrease of quality of life and a drastic deterioration in prognosis. Therefore, to increase the survival of breast cancer patients, the development of new therapeutic strategies to impair metastatic process and skeletal complications is critical. Previous studies on the role of cathepsin K (CTSK) in metastatic spreading led to several strategies for inhibition of this molecule such as MIV-711 (Medivir), balicatib and odanacatib (ODN) which were on trial in the past. The present study intended to assess the anti-metastatic efficacy of ODN in breast cancer cells. Human breast cancer cell lines MDA-MB-231 were treated with different concentrations of ODN and performed invasion, adhesion and migration assays and, RT-PCR and western blot to evaluate the effect of ODN on the metastatic potential of breast cancer cells. ODN markedly decreased wound healing cell migration, invasion and adhesion at a dose dependent manner. ODN inhibits cell invasion by decreasing the matrix metalloproteinase (MMP-9) with the upregulation of TIMP-1 expression. ODN effectively inhibited the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal Kinase (JNK), and blocked the expression of β-integrins and FAK proteins. ODN also significantly inhibited PI3K downstream targets Rac1, Cdc42, paxillin and Src which are critical for cell adhesion, migration and cytoskeletal reorganization. ODN exerts anti-metastatic action through inhibition of signaling pathway for MMP-9, PI3K and MAPK. This indicates potential therapeutic effects of ODN in the treatment of metastatic breast cancer.

Obesity and Cathepsin K: A Complex Pathophysiological Relationship in Breast Cancer Metastases

BACKGROUND

Breast cancer appears in a strong inclination to metastasize in bone tissue. Several strategies are discussed in combating bone metastasis in breast cancer. However, therapy is only palliative and does not provide any improvement in survival to the majority of patients with advanced cancer. Obese and overweight women with breast cancer are three times more likely to develop metastatic disease compared to normal-weight women with the same treatment regimen. Overweight greatly intensify adipocytes formation in the bone marrow affecting bone metabolism by decreasing osteoblast differentiation and bone formation. Cathepsin K (CTSK), a cysteine protease, effectively degrades several components of the extracellular matrix and has the ability to differentiate adipocytes from bone marrow lineage. Therefore, the purpose of this review is to emphasize the underlying mechanism of CTSK and obesity role in breast cancer metastasis.

METHODS

Systematic review was performed using PubMed, EMBASE. The evidence of obesity and CTSK in breast cancer skeletal metastasis were analyzed, summarized and compared.

RESULTS

The present investigation argues for a specific association of CTSK with breast cancer skeletal metastasis by promoting adipocyte differentiation. The potential tumor-supporting roles of adipocytes are well documented, and in fact, suppressing adipocyte could be a new therapeutic option in the battle against lethal metastatic breast cancers.

CONCLUSION

This review emphasizes CTSK through its multifaceted role in differentiating adipocytes, inflammation, and extracellular degradation, may be a critical factor in an obesity-cancer connection. Thus, integration of CTSK targeting strategies into established traditional therapies seems to hold substantial promise.