Neoadjuvant nab-paclitaxel in the treatment of breast cancer

ROS is a master regulator of in vitro matriptase activation

Matriptase is a type II transmembrane serine protease that is widely expressed in normal epithelial cells and epithelial cancers. Studies have shown that regulation of matriptase expression and activation becomes deranged in several cancers and is associated with poor disease-free survival. Although the central mechanism of its activation has remained unknown, our lab has previously demonstrated that inflammatory conditions such as intracellular pH decrease strongly induces matriptase activation. In this investigation, we first demonstrate clear matriptase activation following Fulvestrant (ICI) and Tykerb (Lapatinib) treatment in HER2-amplified, estrogen receptor (ER)-positive BT474, MDA-MB-361 and ZR-75-30 or single ER-positive MCF7 cells, respectively. This activation modestly involved Phosphoinositide 3-kinase (PI3K) activation and occurred as quickly as six hours post treatment. We also demonstrate that matriptase activation is not a universal hallmark of stress, with Etoposide treated cells showing a larger degree of matriptase activation than Lapatinib and ICI-treated cells. While etoposide toxicity has been shown to be mediated through reactive oxygen species (ROS) and MAPK/ERK kinase (MEK) activity, MEK activity showed no correlation with matriptase activation. Novelly, we demonstrate that endogenous and exogenous matriptase activation are ROS-mediated in vitro and inhibited by N-acetylcysteine (NAC). Lastly, we demonstrate matriptase-directed NAC treatment results in apoptosis of several breast cancer cell lines either alone or in combination with clinically used therapeutics. These data demonstrate the contribution of ROS-mediated survival, its independence of kinase-mediated survival, and the plausibility of using matriptase activation to indicate the potential success of antioxidant therapy.

Risk Factors for Chemotherapy-Induced Peripheral Neuropathy Caused by Nanoparticle Albumin-Bound Paclitaxel in Advanced Breast Cancer

Breast cancer (BC) is one of the most common malignancies affecting women and the leading cause of related mortality worldwide. An estimated 2260000 new cases of BC were diagnosed in 2020, which have seriously threatened the health. Paclitaxel (PTX), a natural product isolated from the bark of the pacific yew, has been found to be effective in treating advanced BC. Chemotherapy-induced peripheral neuropathy (CIPN), which refers to the damage to the peripheral nerves caused by exposure to a neurotoxic chemotherapeutic agent, is a common side effect affecting the patients undergoing PTX chemotherapy. Significant research efforts are needed to identify the various risk factors associated with CIPN. Here, a univariate analysis in BC patients with nanonab-PTX treatment was performed. The rate of CIPN in BC patients with albumin-bound paclitaxel (nab-PTX) for more than four weeks was significantly higher than that of patients with chemotherapy for less than four weeks. Moreover, the rate of CIPN in BC patients receiving nab-PTX first-line chemotherapy was remarkably higher than that in BC patients receiving paclitaxel as a sequence scheme. Taken together, chemotherapy cycles and the priority of nab-PTX-based chemotherapy can be considered the potential risk factors for CIPN induced by nab-PTX.

Feasibility Study of Nanoparticle Albumin-Bound-Paclitaxel and S-1 Followed by Epirubicin/Cyclophosphamide as Neoadjuvant Chemotherapy in Patients With Operable Breast Cancer: A Prospective Study

BACKGROUND

The efficacy and safety of nanoparticle albumin-bound (nab)-paclitaxel combined with S-1 in patients with operable breast cancer is uncertain. We evaluated the feasibility of this combination followed by epirubicin/cyclophosphamide (EC) as neoadjuvant chemotherapy in such patients.

PATIENTS AND METHODS

This was an open-label, single-arm, phase II, single-institution prospective study of 4 cycles of nab-paclitaxel (260 mg/m²) administered intravenously on day 1 in combination with S-1 (65 mg/m² orally twice daily) on days 1 to 14 every 21 days followed by EC as neoadjuvant chemotherapy.

RESULTS

Of 30 patients, 1 required a dose interruption for nab-paclitaxel combined with S-1; 4 required a dose reduction for nab-paclitaxel, 1 for S-1, and 4 for EC. Mean relative dose intensities of nab-paclitaxel, S-1, and EC were 98.0%, 99.3%, and 98.2%, respectively. Overall clinical response rate was 96.7%. In histological response, grade 3, pathological complete response (pCR; ypT0/is and ypN0) rate was 63.3% and grade 2b (near pCR) was 3.3%. pCR was observed in 57.1% of luminal B human epidermal growth factor receptor type 2 (HER2)-negative patients, 55.6% of luminal B HER2-positive patients, 100% of HER2-positive patients, and 57.1% of triple-negative breast cancer patients. Grade 3/4 neutropenia was observed in 1 patient during nab-paclitaxel combined with S-1 and in 7 during EC treatments. The most frequent nonhematological severe adverse events were grade 3 peripheral neuropathy in 2 patients and grade 3 arthralgia in 2 patients during nab-paclitaxel combined with S-1.

CONCLUSION

Tri-weekly nab-paclitaxel with S-1 followed by EC is effective and well tolerated as neoadjuvant chemotherapy in patients with operable breast cancer.

Exploring the Influence of Different Albumin Binders on Molecular Imaging Probe Distribution

The biodistribution of molecular imaging probes or tracers mainly depends on the chemical nature of the probe and the preferred metabolization and excretion routes. Small molecules have rather short half-lives while antibodies reside inside the organism for a longer period of time. An excretion via kidneys and bladder is faster than a mainly hepatobiliary elimination. To manipulate the biodistribution behavior of probes, different strategies have been pursued, including utilizing serum albumin as an inherent transport mechanism for small molecules. Here, we modified an existing small molecular fluorescent probe targeted to the endothelin-A receptor (ET_AR) with three different albumin-binding moieties to search for an optimal modification strategy. A diphenylcyclohexyl (DPCH) group, a p-iodophenyl butyric acid (IPBA), and a fatty acid (FA) group were attached via amino acid linkers. All three modifications result in transient albumin binding of the developed compounds, as concluded from gel electrophoresis investigations. Spectrophotometric measurements applying variable amounts of bovine, murine, and human serum albumin (BSA, MSA, and HSA) reveal distinct variations of absorption and emission intensities and shifts of their maximum wavelengths. Binding to MSA results in the weakest effects, while binding to HSA leads to the strongest. Cell-based in vitro investigations utilizing ET_AR-positive HT-1080 fibrosarcoma and ET_AR-negative BT-20 breast adenocarcinoma cells support a retained specific target-binding capacity of the modified compounds and different degrees of unspecific binding. In vivo analysis of a HT-1080 xenograft model in nude mice over the course of 1 week by fluorescence reflectance imaging illustrates noticeable differences between the four examined probes. While the IPBA-modified probe shows the highest absolute signal intensity values, the FA-modified probe exhibits the most favorable tumor-to-organ ratios. In summary, reversible binding to albumin enhances the biological half-life of the designed probes substantially and enables near infrared optical imaging of subcutaneous tumors for several days in vivo. Because the unmodified probe already exhibits reasonable results, the attachment of albumin-binding moieties does not lead to a substantially improved imaging outcome in terms of target-to-background ratios. On the other hand, because the implemented transient albumin binding results in an overall higher amount of probe inside tumor lesions, this strategy might be adaptable for theranostic or therapeutic approaches in a future clinical routine.

When Albumin Meets Liposomes: A Feasible Drug Carrier for Biomedical Applications

Albumin, the most abundant protein in plasma, possesses some inherent beneficial structural and physiological characteristics that make it suitable for use as a drug delivery agent, such as an extraordinary drug-binding capacity and long blood retention, with a high biocompatibility. The use of these characteristics as a nanoparticle drug delivery system (DDS) offers several advantages, including a longer circulation time, lower toxicity, and more significant drug loading. To date, many innovative liposome preparations have been developed in which albumin is involved as a DDS. These novel albumin-containing liposome preparations show superior deliverability for genes, hydrophilic/hydrophobic substances and proteins/peptides to the targeting area compared to original liposomes by virtue of their high biocompatibility, stability, effective loading content, and the capacity for targeting. This review summarizes the current status of albumin applications in liposome-based DDS, focusing on albumin-coated liposomes and albumin-encapsulated liposomes as a DDS carrier for potential medical applications.

Cisplatin prevents breast cancer metastasis through blocking early EMT and retards cancer growth together with paclitaxel

Cancer growth is usually accompanied by metastasis which kills most cancer patients. Here we aim to study the effect of cisplatin at different doses on breast cancer growth and metastasis.

Methods: We used cisplatin to treat breast cancer cells, then detected the migration of cells and the changes of epithelial-mesenchymal transition (EMT) markers by migration assay, Western blot, and immunofluorescent staining. Next, we analyzed the changes of RNA expression of genes by RNA-seq and confirmed the binding of activating transcription factor 3 (ATF3) to cytoskeleton related genes by ChIP-seq. Thereafter, we combined cisplatin and paclitaxel in a neoadjuvant setting to treat xenograft mouse models. Furthermore, we analyzed the association of disease prognosis with cytoskeletal genes and ATF3 by clinical data analysis.

Results: When administered at a higher dose (6 mg/kg), cisplatin inhibits both cancer growth and metastasis, yet with strong side effects, whereas a lower dose (2 mg/kg) cisplatin blocks cancer metastasis without obvious killing effects. Cisplatin inhibits cancer metastasis through blocking early steps of EMT. It antagonizes transforming growth factor beta (TGFβ) signaling through suppressing transcription of many genes involved in cytoskeleton reorganization and filopodia formation which occur early in EMT and are responsible for cancer metastasis. Mechanistically, TGFβ and fibronectin-1 (FN1) constitute a positive reciprocal regulation loop that is critical for activating TGFβ/SMAD3 signaling, which is repressed by cisplatin induced expression of ATF3. Furthermore, neoadjuvant administration of cisplatin at 2 mg/kg in conjunction with paclitaxel inhibits cancer growth and blocks metastasis without causing obvious side effects by inhibiting colonization of cancer cells in the target organs.

Conclusion: Thus, cisplatin prevents breast cancer metastasis through blocking early EMT, and the combination of cisplatin and paclitaxel represents a promising therapy for killing breast cancer and blocking tumor metastasis.

Self-Assembly of pH-Labile Polymer Nanoparticles for Paclitaxel Prodrug Delivery: Formulation, Characterization, and Evaluation

The efficacy of paclitaxel (PTX) is limited due to its poor solubility, poor bioavailability, and acquired drug resistance mechanisms. Designing paclitaxel prodrugs can improve its anticancer activity and enable formulation of nanoparticles. Overall, the aim of this work is to improve the potency of paclitaxel with prodrug synthesis, nanoparticle formation, and synergistic formulation with lapatinib. Specifically, we improve potency of paclitaxel by conjugating it to α-tocopherol (vitamin E) to produce a hydrophobic prodrug (Pro); this increase in potency is indicated by the 8-fold decrease in half maximal inhibitory concentration (IC50) concentration in ovarian cancer cell line, OVCA-432, used as a model system. The efficacy of the paclitaxel prodrug was further enhanced by encapsulation into pH-labile nanoparticles using Flash NanoPrecipitation (FNP), a rapid, polymer directed self-assembly method. There was an 1100-fold decrease in IC50 concentration upon formulating the prodrug into nanoparticles. Notably, the prodrug formulations were 5-fold more potent than paclitaxel nanoparticles. Finally, the cytotoxic effects were further enhanced by co-encapsulating the prodrug with lapatinib (LAP). Formulating the drug combination resulted in synergistic interactions as indicated by the combination index (CI) of 0.51. Overall, these results demonstrate this prodrug combined with nanoparticle formulation and combination therapy is a promising approach for enhancing paclitaxel potency.

Rapid Self-Assembly of Polymer Nanoparticles for Synergistic Codelivery of Paclitaxel and Lapatinib via Flash NanoPrecipitation

Taxol, a formulation of paclitaxel (PTX), is one of the most widely used anticancer drugs, particularly for treating recurring ovarian carcinomas following surgery. Clinically, PTX is used in combination with other drugs such as lapatinib (LAP) to increase treatment efficacy. Delivering drug combinations with nanoparticles has the potential to improve chemotherapy outcomes. In this study, we use Flash NanoPrecipitation, a rapid, scalable process to encapsulate weakly hydrophobic drugs (logP < 6) PTX and LAP into polymer nanoparticles with a coordination complex of tannic acid and iron formed during the mixing process. We determine the formulation parameters required to achieve uniform nanoparticles and evaluate the drug release in vitro. The size of the resulting nanoparticles was stable at pH 7.4, facilitating sustained drug release via first-order Fickian diffusion. Encapsulating either PTX or LAP into nanoparticles increases drug potency (as indicated by the decrease in IC-50 concentration); we observe a 1500-fold increase in PTX potency and a six-fold increase in LAP potency. When PTX and LAP are co-loaded in the same nanoparticle, they have a synergistic effect that is greater than treating with two single-drug-loaded nanoparticles as the combination index is 0.23 compared to 0.40, respectively.

Downregulation of GPSM2 is associated with primary resistance to paclitaxel in breast cancer

Paclitaxel is one of the most effective chemotherapy drugs for breast cancer worldwide but 20–30% patients show primary resistance to the drug. Screening and identification of markers that facilitate effective and rapid prediction of sensitivity to paclitaxel is therefore an urgent medical requirement. In the present study, G protein signaling modulator 2 (GPSM2) mRNA levels were significantly associated with taxane sensitivity in experiments based on the Gene Expression Omnibus (GEO) online database. Immunohistochemical analysis consistently revealed a significant association of GPSM2 protein levels with paclitaxel sensitivity in breast cancer patients. Knockdown of GPSM2 reduced the sensitivity of breast cancer cells to paclitaxel via regulation of the cell cycle. Animal experiments further corroborated our in vitro findings. These results suggest that GPSM2 plays an important role in breast cancer resistance, supporting its utility as a potential target for improving drug susceptibility in patients as well as a marker of paclitaxel sensitivity.

Application of the CRISPR/Cas9 System to Drug Resistance in Breast Cancer

Clinical evidence indicates that drug resistance is a great obstacle in breast cancer therapy. It renders the disease uncontrollable and causes high mortality. Multiple mechanisms contribute to the development of drug resistance, but the underlying cause is usually a shift in the genetic composition of tumor cells. It is increasingly feasible to engineer the genome with the clustered regularly interspaced short palindromic repeats (CRISPR)/associated (Cas)9 technology recently developed, which might be advantageous in overcoming drug resistance. This article discusses how the CRISPR/Cas9 system might revert resistance gene mutations and identify potential resistance targets in drug-resistant breast cancer. In addition, the challenges that impede the clinical applicability of this technology and highlight the CRISPR/Cas9 systems are presented. The CRISPR/Cas9 system is poised to play an important role in preventing drug resistance in breast cancer therapy and will become an essential tool for personalized medicine.

Paclitaxel increases the sensitivity of lung cancer cells to lobaplatin via PI3K/Akt pathway

The effect of paclitaxel combined with lobaplatin on the sensitivity of lung cancer cell line NCI-H446 through influencing the phosphatidylinositol 3-kinase (PI3K)/Akt pathway was investigated. The sensitivity of lobaplatin to NCI-H446 and the effect of paclitaxel and PI3K inhibitor LY294002 combined with lobaplatin on the sensitivity to NCI-H446 were detected via methyl thiazolyltetrazolium (MTT) assay. The effect of paclitaxel combined with lobaplatin on cell apoptosis was detected using flow cytometry, the effect of paclitaxel combined with lobaplatin on the cell migration was detected via cell wound scratch assay, and the effect of paclitaxel combined with lobaplatin on the cell invasion was detected via Transwell assay. Finally, the effect of paclitaxel on PI3K/Akt pathway was detected via western blotting. MTT assay showed that 30 µg/ml lobaplatin could significantly inhibit the growth of NCI-H446 (p<0.01). Lobaplatin group (group L), 2 µg/ml paclitaxel combined with lobaplatin group (group LP) and lobaplatin combined with 10 µmol/ml LY294002 group (group LL) were set up. The cell survival rates in group LP and group LL were significantly lower than that in group L (p<0.01), and the cell survival rate in group LP was similar to that in group LL (p>0.05). Flow cytometry revealed that the cell apoptotic levels in group LP and group LL were obviously higher than that in group L (p<0.01), and there was no statistically significant difference in the cell apoptotic level between group LP and group LL (p>0.05). Cell wound scratch assay showed that the cell migration capacity in group LP was significantly lower than those in group L and group LL (p<0.01, p<0.05), and the cell migration capacity in group LL was lower than that in group L (p<0.05). Besides, Transwell assay revealed that the cell invasion capacity in group LP was obviously lower than those in group L and group LL (p<0.01, p<0.05), and the cell invasion capacity in group LL was lower than that in group L (p<0.01). Finally, western blotting showed that the levels of PI3K, phosphorylated-Akt (p-Akt) and phosphorylated-glycogen synthase kinase 3β (p-GSK3β) in group LP and group LL were significantly lower than those in group L, and the differences were statistically significant (p<0.01). Paclitaxel can significantly increase the sensitivity of lobaplatin to lung cancer cell line NCI-H446. Moreover, paclitaxel can enhance the effect of lobaplatin on lung cancer cells and reduce the drug resistance through inhibiting PI3K/Akt pathway.

Nab-paclitaxel after docetaxel hypersensitivity reaction: case report and literature review

Taxanes, including paclitaxel and docetaxel, are one of the most active cytotoxic agents in breast cancer  treatment  including  Her-2  positive  subtype characterized  by  aggressive  clinical  and pathological features since the early stage. However, their use is sometimes limited by the occurrence of hypersensivity reactions (HSRs) characterized by erythematous rashes, bronchospasm, respiratory distress, hypotension, and pulmonary edema. Cross-reactions between paclitaxel and docetaxel are described in literature with a rate ranging from 49% to 90%. Abraxane (nab-paclitaxel), an albumin-bound form of paclitaxel, has a different toxicity profile from solvent-based paclitaxel and a lower rate of HSRs. Interestingly, several authors have recently reported cases of patients who developed HSRs to taxanes, principally paclitaxel, and were then safety treated with Abraxane, suggesting the absence of cross-reactivity between these drugs. Based on these considerations, we report our clinical experience and perform a literature review on this topic with the aim to investigate the cross-reactivity between nab-paclitaxel and other taxanes, in particular with docetaxel.

Pixuna virus modifies host cell cytoskeleton to secure infection

Pixuna virus (PIXV) is an enzootic member of the Venezuelan Equine Encephalitis Virus complex and belongs to the New World cluster of alphaviruses. Herein we explore the role of the cellular cytoskeleton during PIXV replication. We first identified that PIXV undergoes an eclipse phase consisting of 4 h followed by 20 h of an exponential phase in Vero cells. The infected cells showed morphological changes due to structural modifications in actin microfilaments (MFs) and microtubules (MTs). Cytoskeleton-binding agents, that alter the architecture and dynamics of MFs and MTs, were used to study the role of cytoskeleton on PIXV replication. The virus production was significantly affected (p < 0.05) after treatment with paclitaxel or nocodazole due to changes in the MTs network. Interestingly, disassembly of MFs with cytochalasin D, at early stage of PIXV replication cycle, significantly increased the virus yields in the extracellular medium (p < 0.005). Furthermore, the stabilization of actin network with jasplakinolide had no effect on virus yields. Our results demonstrate that PIXV relies not only on intact MTs for the efficient production of virus, but also on a dynamic actin network during the early steps of viral replication.

Efficacy and safety of nab-paclitaxel 125 mg/m2 and nab-paclitaxel 150 mg/m2 compared to paclitaxel in early high-risk breast cancer. Results from the neoadjuvant randomized GeparSepto study (GBG 69)

PURPOSE

The GeparSepto study demonstrated that the use of nab-paclitaxel instead of paclitaxel prior to anthracycline-based chemotherapy could lead to a significantly increased pCR rate, especially in the triple negative subpopulation. We report efficacy and safety for patients treated with two different doses of nab-paclitaxel in comparison to weekly solvent-formulated paclitaxel.

METHODS

Patients were treated for 12 weeks with either intravenous nab-paclitaxel 150 mg/m² (nP150) weekly, after study amendment 125 mg/m² (nP125) weekly or solvent-based paclitaxel 80 mg/m² (P80) weekly followed by epirubicin 90 mg/m² and cyclophosphamide 600 mg/m² on day 1 for four 3-week cycles.

RESULTS

229 patients received nP150, 377 nP125. Baseline characteristics were fairly balanced between these two sequential cohorts as well as compared to 601 patients receiving P80 except for hormone receptor status, HER2 status, and Ki67. Taxane treatment was discontinued in 26.8% (nP150), 16.6% (nP125), and 13.3% of (P80) patients, respectively. Median relative total dose intensity (mRTDI) based on 125 mg/m² for nP was 103% with nP150, 95% with nP125, 99% with P80 before and 98% with P80 after the amendment. PSN grade 3-4 was observed in 14.5% of patients with nP150, 8.1% of patients with nP125 (p = 0.018), and 2.7% of patients with P80. Overall pCR before the amendment was 33.6% after nP150 and 23.5% after P80 (OR 1.65 [95% CI 1.10-2.50]; p = 0.022); pCR after the amendment was 41.4% after nP125, and 32.4% after P80 (1.48 [95% CI 1.10-1.99]; p = 0.013).

CONCLUSIONS

Nab-paclitaxel 125 mg/m² was associated with a better safety profile and compliance without compromising the efficacy compared to nab-paclitaxel 150 mg/m².

Nab-paclitaxel after docetaxel hypersensitivity reaction: case report and literature review

Taxanes, including paclitaxel and docetaxel, are one of the most active cytotoxic agents in breast cancer  treatment  including  Her-2  positive  subtype characterized  by  aggressive  clinical  and pathological features since the early stage. However, their use is sometimes limited by the occurrence of hypersensivity reactions (HSRs) characterized by erythematous rashes, bronchospasm, respiratory distress, hypotension, and pulmonary edema. Cross-reactions between paclitaxel and docetaxel are described in literature with a rate ranging from 49% to 90%. Abraxane (nab-paclitaxel), an albumin-bound form of paclitaxel, has a different toxicity profile from solvent-based paclitaxel and a lower rate of HSRs. Interestingly, several authors have recently reported cases of patients who developed HSRs to taxanes, principally paclitaxel, and were then safety treated with Abraxane, suggesting the absence of cross-reactivity between these drugs. Based on these considerations, we report our clinical experience and perform a literature review on this topic with the aim to investigate the cross-reactivity between nab-paclitaxel and other taxanes, in particular with docetaxel.