Competitive ELISA method for novel estrogen-negative breast cancer biomarker quantitation

NOHA: A Promising Biomarker for Determining Estrogen Receptor Status Among Patients With Breast Cancer in Resource-Constrained Settings

PURPOSE

Challenges to breast cancer control in low-and middle-income countries exist because of constrained access to care, including pathology services. Immunohistochemistry (IHC)-based estrogen receptor (ER) analysis is limited-nonexistent because of few and inadequately staffed and equipped pathology laboratories. We have identified N^w-hydroxy-L-Arginine (NOHA) as a blood-based biomarker to distinguish ER status in US patients with breast cancer. Here, we examine NOHA's clinical utility as an ER IHC alternative in Tanzanian patients.

MATERIALS AND METHODS

Following informed consent, 70 newly diagnosed, known or suspected patients with breast cancer were enrolled at Kilimanjaro Christian Medical Center; basic, deidentified clinical and sociodemographic data were collected. For each, a needle prick amount of blood was collected on a Noviplex plasma card and stored at -80°C. Plasma cards and unstained tumor pathology slides were shipped regularly to US laboratories for NOHA, histologic and IHC analysis. NOHA and IHC assay operators were blinded to each other's result and patient clinical status. Paired NOHA and IHC results were compared.

RESULTS

Slides from 43 participants were available for pathological analysis in the United States. Of those with confirmed malignancy (n = 39), 44%, 51%, 5% were ER-positive, ER-negative, and ER inconclusive, respectively. NOHA levels were available among 33 of 43 of those with pathological data and showed distinct threshold levels correlating 100% to tumor ER IHC and disease categorization where a level below 4 nM, from 4 to 8 nM, and above 8 nM signified ER-negative, ER-positive, and no cancer, respectively.

CONCLUSION

The results are consistent with findings from US patients and suggest NOHA's clinical utility as an accessible IHC replacement in determining ER status among low-and middle-income country patients with breast cancer, promising to extend access to cost-efficient, available hormonal agents and improve outcomes.

Current and future applications of biomarkers in samples collected through minimally invasive methods for cancer medicine and population-based research

Despite advances in cancer medicine and research, invasive and potentially risky procedures such as biopsies, venous blood tests, imaging, colonoscopy, and pap smear tests are still primarily used for screening, staging, and assessing response to therapy. The development and interdisciplinary use of biomarkers from urine, feces, saliva, scent, and capillary blood collected with minimally invasive methods represents a potential opportunity for integration with biomarker analysis for cancers, both in clinical practice (e.g., in screening, treatment, and disease monitoring, and improved quality of life for patients) and population-based research (e.g., in epidemiology/public health, studies of social and environmental determinants, and evolutionary medicine). In this article, we review the scientific rationale, benefits, challenges, and potential opportunities for measuring cancer-related biomarkers in samples collected through minimally invasive methods.

A new strategy to design label-free electrochemical biosensor for ultrasensitive diagnosis of CYFRA 21-1 as a biomarker for detection of non-small cell lung cancer

Lung cancer is one of the most dangerous cancers with high mortality rate among other cancers therefore, early detection of this cancer is very important. Many studies have been reported in ways of diagnostic lung cancer early. According to reports, one of the most important biomarkers to detect lung cancer is Cytokeratin 19 fragment 21-1 (CYFRA21-1), which is significantly related to non-small cell lung cancer, in particular, squamous cell carcinoma. Thus, finding a new method for the early diagnosis of CYFRA 21-1 (DNA target probe) is essential. In the present report, we design a novel label-free electrochemical DNA-biosensor related to the signal of guanine oxidation. The proposed DNA biosensor is fabricated by a modified glassy carbon electrode (GCE) with reduced-graphene oxide (rGO), poly pyrrole (PPy), silver nanoparticles (AgNPs) and single-strand DNA (ssDNA as capture probe) GCE/rGO/PPy/AgNPs/ssDNA. The differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques are used to verify the hybridization process between capture and target probes. Electrochemical impedance spectroscopy (EIS), energy diffraction X-ray (EDX) and field-emission scanning microscopy (FE-SEM) techniques are applied to the characterization of different modified GCE surfaces as well as X-ray diffraction (XRD) for graphene oxide synthesis. The XRD pattern of the synthesized GO that its diffraction peak appears at 10.2. The applied CV and DPV for the guanine oxidation are determined under optimal conditions. The label-free DNA biosensor showed a great result for the determination of CYFRA21-1 with a wide linear range from two consecutive linear relationships of peak current and CYFRA21-1 concentration were found (1.0 × 10^-14 - 1.0 × 10^-10 M, R² = 0.9936 and 1.0 × 10^-9 - 1.0 × 10^-6 M, R² = 0.9955). Proposed electrochemical biosensor displayed low detection limit (2.4 fM).

Role of chemokines in breast cancer

Chemokines belong to a family of chemoattractant cytokines and are well known to have an essential role in various cancer aetiologies. Multiplesubsets of immune cells are recruited and enrolled into the tumor microenvironment through interactions between chemokines and their specific receptors. These populations and their interactions have a distinct impact on tumor growth, progression, and treatment outcomes. While it is clear that many chemokines and their cognate receptors can be detected in breast and other cancers, the role of each chemokine and receptor has yet to be determined. This review focuses on the main chemokines that play a crucial role in the tumor microenvironment, emphasizing breast cancer. We have also discussed the techniques used to identify the chemokines and their future implication in the early diagnosis of cancer. In-depth knowledge of chemokines and their role in breast cancer progression can provide specific targets for breast cancer biotherapy.

Assessing the predictive response of a simple and sensitive blood-based biomarker between estrogen-negative solid tumors

PURPOSE

We investigated N^w-hydroxy l-Arginine (NOHA) predictive response in serous ovarian carcinoma based on estrogen-hormone receptor expression status; and assessed the distinctive NOHA response between estrogen-receptor-negative (ER-) tumor subtypes of ovarian and breast cancer.

MATERIALS/METHODS

Three-dimensional (3D) spheroids models of ER- and estrogen-receptor-positive (ER+) from breast and ovarian tumor, cultured for 9 weeks, were assayed for cellular levels of inducible nitric oxide synthase (NOS2), nitric oxide (as total nitrite) and l-Arginine, and compared to NOHA in culture medium. Statistical difference was set at p < 0.01.

RESULTS

Nine-week in vitro studies showed a progressive NOHA reduction in culture medium by at least 0.4-0.8 fold, and 0.65-0.92 fold only in the ER- breast tumor and ER- ovarian tumor 3D spheroids, respectively; with increases in cellular NOS2 and nitric-oxide levels, by at least 1.0-2.45 fold in both ER- tumor subtype 3D spheroids (p < 0.01; n = 6). Within ER- subtypes, medium NOHA decreased by ≥ 38.9% in ovarian cancer over breast cancer 3D-spheroids, with cellular increases in NOS2 (by ≥ 17.4%), and nitric oxide (by ≥ 18.8%). Cellular l-Arginine to medium NOHA ratio was higher, and by at least 6.5-22.5 fold in ER- breast tumor 3D-spheroids, and at least 10-70 fold in ER- ovarian tumor 3D spheroids, than in ER+ and control conditions; and was ≥48% higher in ER- ovarian cancer than in ER- breast cancer 3D-spheroids.

CONCLUSIONS

The present study shows NOHA as a sensitive and selective indicator differentiating and distinguishing ER- subtypes based on the tumor grade.