Annexin A3 Is a Potential Predictor of Platinum Resistance in Epithelial Ovarian Cancer Patients in a Prospective Cohort

Platinum-resistant ovarian cancer: From drug resistance mechanisms to liquid biopsy-based biomarkers for disease management

Resistance to platinum-based chemotherapy is a major clinical challenge in ovarian cancer, contributing to the high mortality-to-incidence ratio. Management of the platinum-resistant disease has been difficult due to diverse underlying molecular mechanisms. Over the past several years, research has revealed several novel molecular targets that are being explored as biomarkers for treatment planning and monitoring of response. The therapeutic landscape of ovarian cancer is also rapidly evolving, and alternative therapies are becoming available for the recurrent platinum-resistant disease. This review provides a snapshot of platinum resistance mechanisms and discusses liquid-based biomarkers and their potential utility in effective management of platinum-resistant ovarian cancer.

Exosomal annexin A6 induces gemcitabine resistance by inhibiting ubiquitination and degradation of EGFR in triple-negative breast cancer

Exosomes are carriers of intercellular information that regulate the tumor microenvironment, and they have an essential role in drug resistance through various mechanisms such as transporting RNA molecules and proteins. Nevertheless, their effects on gemcitabine resistance in triple-negative breast cancer (TNBC) are unclear. In the present study, we examined the effects of exosomes on TNBC cell viability, colony formation, apoptosis, and annexin A6 (ANXA6)/EGFR expression. We addressed their roles in gemcitabine resistance and the underlying mechanism. Our results revealed that exosomes derived from resistant cancer cells improved cell viability and colony formation and inhibited apoptosis in sensitive cancer cells. The underlying mechanism included the transfer of exosomal ANXA6 from resistant cancer cells to sensitive cancer cells. Isobaric peptide labeling–liquid chromatography–tandem mass spectrometry and western blotting revealed that ANXA6 was upregulated in resistant cancer cells and their derived exosomes. Sensitive cancer cells exhibited resistance with increased viability and colony formation and decreased apoptosis when ANXA6 was stably overexpressed. On the contrary, knockdown ANXA6 restored the sensitivity of cells to gemcitabine. Co-immunoprecipitation expression and GST pulldown assay demonstrated that exosomal ANXA6 and EGFR could interact with each other and exosomal ANXA6 was associated with the suppression of EGFR ubiquitination and downregulation. While adding lapatinib reversed gemcitabine resistance induced by exosomal ANXA6. Moreover, ANXA6 and EGFR protein expression was correlated in TNBC tissues, and exosomal ANXA6 levels at baseline were lower in patients with highly sensitive TNBC than those with resistant TNBC when treated with first-line gemcitabine-based chemotherapy. In conclusion, resistant cancer cell-derived exosomes induced gemcitabine resistance via exosomal ANXA6, which was associated with the inhibition of EGFR ubiquitination and degradation. Exosomal ANXA6 levels in the serum of patients with TNBC might be predictive of the response to gemcitabine-based chemotherapy.

Annexin A3 in sepsis: novel perspectives from an exploration of public transcriptome data

According to publicly available transcriptome datasets, the abundance of Annexin A3 (ANXA3) is robustly increased during the course of sepsis; however, no studies have examined the biological significance or clinical relevance of ANXA3 in this pathology. Here we explored this interpretation gap and identified possible directions for future research. Based on reference transcriptome datasets, we found that ANXA3 expression is restricted to neutrophils, is upregulated in vitro after exposure to plasma obtained from septic patients, and is associated with adverse clinical outcomes. Secondly, an increase in ANXA3 transcript abundance was also observed in vivo, in the blood of septic patients in multiple independent studies. ANXA3 is known to mediate calcium-dependent granules-phagosome fusion in support of microbicidal activity in neutrophils. More recent work has also shown that ANXA3 enhances proliferation and survival of tumour cells via a Caspase-3-dependent mechanism. And this same molecule is also known to play a critical role in regulation of apoptotic events in neutrophils. Thus, we posit that during sepsis ANXA3 might either play a beneficial role, by facilitating microbial clearance and resolution of the infection; or a detrimental role, by prolonging neutrophil survival, which is known to contribute to sepsis-mediated organ damage.

A systematic literature review assessing if genetic biomarkers are predictors for platinum-based chemotherapy response in ovarian cancer patients

BACKGROUND

Ovarian cancer is the deadliest of gynecologic malignancies with the 5-year overall survival rate remaining at approximately 30%, a rate that has not improved over the last three decades. Standard of care for epithelial ovarian cancer patients consists of a platinum compound with a taxane given intravenously following debulking surgery; however, 80% of cases relapse within 2 years of diagnosis. This review sought to identify key underlying biomarkers related to platinum resistance in ovarian cancer to establish possible prognostic biomarkers of chemoresponse.

METHODS

A systematic literature review was conducted across three databases PubMed, EMBASE and SCOPUS to summarise the evidence for prognostic biomarkers in platinum-resistant ovarian cancer patients.

RESULTS

Forty-eight human studies were used in the review encompassing 6719 participants in retrospective and prospective study designs. A total of 68 biomarkers were reported that were significantly correlated with chemoresponse and/or survival reporting a p value less than or equal to 0.05.

CONCLUSION

This review accentuates the pleiotropic phenotypic complexities related to the response to platinum therapy in ovarian cancer. A one-size-fits-all approach may be ineffective in a large portion of patients, emphasising the need for a whole system-based approach and personalised treatment strategies. Identifying key biomarkers to aid clinical decision-making is the first essential step in developing and appropriating therapies for at-risk patients, reducing toxicity and improving quality of life.

Differential proteomic analysis of synovial fluid from hip arthroplasty patients with a pseudotumor vs. Periprosthetic osteolysis

Adverse tissue reactions to metal implants, including pseudotumors, can compromise implant functionality and survivorship. The identification of specific proteins in the synovial fluid (SF) of hip arthroplasty patients with a pseudotumor may lead to a better understanding of the underlying pathomechanisms. The objective of the present study was to compare the protein content of SF from patients with a short-term metal-on-metal hip implant associated with a pseudotumor and patients with a long-term metal-on-polyethylene hip implant associated with periprosthetic osteolysis. Discovery proteomics was used to identify differentially abundant proteins in albumin-depleted SF. In toto, 452 distinct proteins (present in at least half of the patients in one or both groups) were identified. Thirty of these 452 proteins were differentially abundant between the two groups, including two potential biomarkers: 6-phosphogluconate dehydrogenase (which plays a major protective role against oxidative stress) for the pseudotumor group, and scavenger receptor cysteine-rich type 1 protein M130 (which is involved in low-grade inflammation) for the periprosthetic osteolysis group. Other differentially abundant proteins identified suggest the presence of an adaptive immune response (particularly a type-IV hypersensitivity reaction), necrosis, and greater oxidative stress in patients with a pseudotumor. They also suggest the presence of an innate immune response, oxidative stress, tissue remodeling, and apoptosis in both patient groups, although differences in the specific proteins identified in each group point to differences in the pathomechanisms. Overall, results provide insights into the molecular mechanisms underlying metal-related pseudotumors and periprosthetic osteolysis, and may ultimately help elucidate pseudotumor etiology and assess the risk that asymptomatic pseudotumors will develop into an aggressive lesion. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1849-1859, 2018.

Application of Serum Annexin A3 in Diagnosis, Outcome Prediction and Therapeutic Response Evaluation for Patients with Hepatocellular Carcinoma

PURPOSE

Annexin A3 (ANXA3) could induce progression of hepatocellular carcinoma (HCC) via promoting stem cell traits of CD133-positive cells. Moreover, serum ANXA3 showed preliminary diagnostic potential, however further validation was required. Meanwhile, the prognostic value of ANXA3 remained elusive. The present study aimed to validate diagnostic performance and further systematically investigate the prognostic value of serum ANXA3.

METHODS

Serum ANXA3 of 368 HCC patients was determined by enzyme-linked immunosorbent assay (ELISA); 295 of these patients underwent resection and 73 underwent transcatheter arterial chemoembolization (TACE). Diagnostic performance of ANXA3 was evaluated by receiver operating characteristic (ROC) analysis, and the prognostic value was evaluated by Cox regression and Kaplan-Meier analysis. To evaluate the relationship between serum ANXA3 and circulating CD133 mRNA-positive tumor cells (CD133^mRNA+ CTCs), real-time polymerase chain reaction was conducted in 69 patients who underwent resection.

RESULTS

Serum ANXA3 provided greater diagnostic performance than α-fetoprotein (area under the curve [AUC] 0.869 vs. 0.782), especially in early diagnosis (AUC 0.852 vs. 0.757) and discriminating HCC from patients at risk (0.832 vs. 0.736). Pretreatment ANXA3 was an independent predictor of tumor recurrence (hazard ratio [HR] 1.87, 95% confidence interval [CI] 1.26-2.76, p = 0.002)/progression (HR 1.88, 95% CI 1.04-3.43, p = 0.038) and survival (resectable: HR 2.26, 95% CI 1.44-3.56, p = 0.001; unresectable: HR 2.08, 95% CI 1.10-4.05, p = 0.025), and retained its performance in low-recurrence-risk subgroups. Specifically, dynamic changes of ANXA3-positive status was associated with worse prognosis. ANXA3 was positively correlated with CD133^mRNA+ CTCs (r = 0.601, p < 0.001). In patients with detectable CD133^mRNA+ CTC, high ANXA3 was positively associated with a higher risk of recurrence and shorter overall survival.

CONCLUSIONS

Serum ANXA3 shows promise as a biomarker for diagnosis, outcome prediction, and therapeutic response evaluation in patients with HCC.

Role of BRCA Mutations in the Modulation of Response to Platinum Therapy

Recent years have seen cancer emerge as one of the leading cause of mortality worldwide with breast cancer being the second most common cause of death among women. Individuals harboring BRCA mutations are at a higher risk of developing breast and/or ovarian cancers. This risk is much greater in the presence of germline mutations. BRCA1 and BRCA2 play crucial role in the DNA damage response and repair pathway, a function that is critical in preserving the integrity of the genome. Mutations that interfere with normal cellular function of BRCA not only lead to onset and progression of cancer but also modulate therapy outcome of treatment with platinum drugs. In this review, we discuss the structural and functional impact of some of the prevalent BRCA mutations in breast and ovarian cancers and their role in platinum therapy response. Understanding the response of platinum drugs in the context of BRCA mutations may contribute toward developing better therapeutics that can improve survival and quality of life of patients.

Role of BRCA Mutations in the Modulation of Response to Platinum Therapy

Recent years have seen cancer emerge as one of the leading cause of mortality worldwide with breast cancer being the second most common cause of death among women. Individuals harboring BRCA mutations are at a higher risk of developing breast and/or ovarian cancers. This risk is much greater in the presence of germline mutations. BRCA1 and BRCA2 play crucial role in the DNA damage response and repair pathway, a function that is critical in preserving the integrity of the genome. Mutations that interfere with normal cellular function of BRCA not only lead to onset and progression of cancer but also modulate therapy outcome of treatment with platinum drugs. In this review, we discuss the structural and functional impact of some of the prevalent BRCA mutations in breast and ovarian cancers and their role in platinum therapy response. Understanding the response of platinum drugs in the context of BRCA mutations may contribute toward developing better therapeutics that can improve survival and quality of life of patients.