Novel immunotherapies for breast cancer: Focus on 2023 findings.

Immunotherapy has emerged as a revolutionary approach in cancer therapy, and recent advancements hold significant promise for breast cancer (BCa) management. Employing the patient's immune system to combat BCa has become a focal point in immunotherapeutic investigations. Strategies such as immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT), and targeting the tumor microenvironment (TME) have disclosed encouraging clinical outcomes. ICIs, particularly programmed cell death protein 1 (PD-1)/PD-L1 inhibitors, exhibit efficacy in specific BCa subtypes, including triple-negative BCa (TNBC) and human epidermal growth factor receptor 2 (HER2)-positive cancers. ACT approaches, including tumor-infiltrating lymphocytes (TILs) and chimeric antigen receptor (CAR) T-cell therapy, showed promising clinical outcomes in enhancing tumor recognition and elimination. Targeting the TME through immune agonists and oncolytic viruses signifies a burgeoning field of research. While challenges persist in patient selection, resistance mechanisms, and combination therapy optimization, these novel immunotherapies hold transformative potential for BCa treatment. Continued research and clinical trials are imperative to refine and implement these innovative approaches, paving the way for improved outcomes and revolutionizing the management of BCa. This review provides a concise overview of the latest immunotherapies (2023 studies) in BCa, highlighting their potential and current status.

Bispecific antibodies revolutionizing breast cancer treatment: a comprehensive overview.

Breast cancer (BCa) is known as a complex and prevalent disease requiring the development of novel anticancer therapeutic approaches. Bispecific antibodies (BsAbs) have emerged as a favorable strategy for BCa treatment due to their unique ability to target two different antigens simultaneously. By targeting tumor-associated antigens (TAAs) on cancer cells, engaging immune effector cells, or blocking critical signaling pathways, BsAbs offer enhanced tumor specificity and immune system involvement, improving anti-cancer activity. Preclinical and clinical studies have demonstrated the potential of BsAbs in BCa. For example, BsAbs targeting human epidermal growth factor receptor 2 (HER2) have shown the ability to redirect immune cells to HER2-positive BCa cells, resulting in effective tumor cell killing. Moreover, targeting the PD-1/PD-L1 pathway by BsAbs has demonstrated promising outcomes in overcoming immunosuppression and enhancing immune-mediated tumor clearance. Combining BsAbs with existing therapeutic approaches, such as chemotherapy, targeted therapies, or immune checkpoint inhibitors (ICIs), has also revealed synergistic effects in preclinical models and early clinical trials, emphasizing the usefulness and potential of BsAbs in BCa treatment. This review summarizes the latest evidence about BsAbs in treating BCa and the challenges and opportunities of their use in BCa.

Myricetin exhibits anti-glioma potential by inducing mitochondrial-mediated apoptosis, cell cycle arrest, inhibition of cell migration and ROS generation.

The Editors of JBUON issue an Expression of Concern to 'Myricetin exhibits anti-glioma potential by inducing mitochondrial-mediated apoptosis, cell cycle arrest, inhibition of cell migration and ROS generation', by Hu-Guang Li, Jun-Xia Chen, Jun-Hui Xiong, Jin-Wei Zhu, JBUON 2016;21(1):182-190; PMID:27061547. Following the publication of the above article, readers drew to our attention that part of the data was possibly unreliable. We sent emails to the authors with a request to provide the raw data to prove the originality, but received no reply. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.

Myricetin exhibits anti-glioma potential by inducing mitochondrial-mediated apoptosis, cell cycle arrest, inhibition of cell migration and ROS generation.

PURPOSE: To study the antiproliferative effects of myricetin in human glioma U251 cells together with assessing its effects on cell cycle, apoptosis, apoptosis-related proteins, reactive oxygen species (ROS) generation and cell migration. METHODS: Cell viability of human glioma cells after myricetin treatment was assessed by MTT assay. Phase-contrast and confocal fluorescence microscopies were used to assess the morphological changes that occured in these cells following myricetin treatment. Flow cytometry using propidium iodide (PI) and Annexin-V FITC as probes was employed to evaluate the effects on cell cycle arrest and apoptosis induction, respectively. The effect of myricetin on intracellular ROS production was measured by flow cytometry with a fluorescent probe CM-DCFH2-DA. RESULTS: Myricetin induced a dose-dependent as well as time-dependent growth inhibitory effect in U251 human glioma cells. Myricetin treatment resulted in U251 cells detachment from adjacent cells making clusters of cells floating in the medium. Detached cells had irregular shape and incapable to maintain their membranes intact. Apoptotic cell death was induced by myricetin treatment as witnessed by fluorescence microscopy. The percentage of early and late apoptotic cells increased from 0.41% and 8.2% to 23.1% and 10.2%, 25.2% and 19.4%, to finally 36.2% and 28.4% after treatment with 15 µM, 60 µM and 120 µM of myricetin, respectively. We also observed a dose-dependent increase in Bax and Bad levels and a dose-dependent decrease in Bcl-2 and Bcl-xl expression levels following myricetin treatment. Cell cycle arrest in G2/M phase of the cell cycle was also induced by the drug treatment. A concentration-dependent ROS generation was also witnessed and a 3-fold increase of ROS production was seen after 60 µM myricetin treatment. CONCLUSION: Myricetin exerts anticancer effects in U251 human glioma cells by inducing mitochondrial-mediated apoptosis, G2/M phase cell cycle arrest, ROS generation and inhibition of cell migration.

Ribonuclease inhibitor up-regulation inhibits the growth and induces apoptosis in murine melanoma cells through repression of angiogenin and ILK/PI3K/AKT signaling pathway.

Human ribonuclease inhibitor (RI), a cytoplasmic protein, is constructed almost entirely of leucine rich repeats. RI could suppress activities of ribonuclease and angiogenin (ANG) through closely combining with them. ANG is a potent inducer of blood vessel growth and has been implicated in the establishment, growth, and metastasis of tumors. ILK/PI3K/AKT signaling pathway also plays important roles in cell growth, cell-cycle progression, tumor angiogenesis, and cell apoptosis. Our previous experiments demonstrated that RI might effectively inhibit some tumor growth and metastasis. Our recent study showed that ILK siRNA inhibited the growth and induced apoptosis in bladder cancer cells as well as increased RI expression, which suggest a correlation between RI and ILK. However, the exact molecular mechanism of RI in anti-tumor and in the cross-talk of ANG and ILK signaling pathway remains largely unknown. Here we investigated the effects of up-regulating RI on the growth and apoptosis in murine melanoma cells through angiogenin and ILK/PI3K/AKT signaling pathway. We demonstrated that up-regulating RI obviously decreased ANG expression and activity. We also discovered that RI overexpression could remarkably inhibit cell proliferation, regulate cell cycle and induce apoptosis. Furthermore, up-regulation of RI inhibited phosphorylation of ILK downstream signaling targets protein kinase B/Akt, glycogen synthase kinase 3-beta (GSK-3ß), and reduced ß-catenin expression in vivo and vitro. More importantly, RI significant inhibited the tumor growth and angiogenesis of tumor bearing C57BL/6 mice. In conclusion, our findings, for the first time, suggest that angiogenin and ILK signaling pathway plays a pivotal role in mediating the inhibitory effects of RI on melanoma cells growth. This study identifies that RI may be a useful molecular target for melanoma therapy.

A novel role of ribonuclease inhibitor in regulation of epithelial-to-mesenchymal transition and ILK signaling pathway in bladder cancer cells.

Human ribonuclease inhibitor (RI) is a cytoplasmic acidic protein possibly involved in biological functions other than the inhibition of RNase A and angiogenin activities. We have previously shown that RI can inhibit growth and metastasis in some cancer cells. Epithelial-mesenchymal transition (EMT) is regarded as the beginning of invasion and metastasis and has been implicated in the metastasis of bladder cancer. We therefore postulate that RI regulates EMT of bladder cancer cells. We find that the over-expression of RI induces the up-regulation of E-cadherin, accompanied with the decreased expression of proteins associated with EMT, such as N-cadherin, Snail, Slug, vimentin and Twist and of matrix metalloprotein-2 (MMP-2), MMP-9 and Cyclin-D1, both in vitro and in vivo. The up-regulation of RI inhibits cell proliferation, migration and invasion, alters cell morphology and adhesion and leads to the rearrangement of the cytoskeleton in vitro. We also demonstrate that the up-regulation of RI can decrease the expression of integrin-linked kinase (ILK), a central component of signaling cascades controlling an array of biological processes. The over-expression of RI reduces the phosphorylation of the ILK downstream signaling targets p-Akt and p-GSK3ß in T24 cells. We further find that bladder cancer with a high-metastasis capability shows higher vimentin, Snail, Slug and Twist and lower E-cadherin and RI expression in human clinical specimens. Finally, we provide evidence that the up-regulation of RI inhibits tumorigenesis and metastasis of bladder cancer in vivo. Thus, RI might play a novel role in the development of bladder cancer through regulating EMT and the ILK signaling pathway.

Parameters optimization of supercritical fluid-CO2 extracts of frankincense using response surface methodology and its pharmacodynamics effects.

The volatile oil parts of frankincense (Boswellia carterii Birdw.) were extracted with supercritical carbon dioxide under constant pressure (15, 20, or 25 MPa) and fixed temperature (40, 50, or 60°C), given time (60, 90, or 120 min) aiming at the acquisition of enriched fractions containing octyl acetate, compounds of pharmaceutical interest. A mathematical model was created by Box-Behnken design, a popular template for response surface methodology, for the extraction process. The response value was characterized by synthetical score, which comprised yields accounting for 20% and content of octyl acetate for 80%. The content of octyl acetate was determined by GC. The supercritical fluid extraction showed higher selectivity than conventional steam distillation. Supercritical fluid-CO(2) for extracting frankincense under optimum condition was of great validity, which was also successfully verified by the pharmacological experiments.

Small interfering RNA targeting integrin-linked kinase inhibited the growth and induced apoptosis in human bladder cancer cells.

Integrin-linked kinase (ILK), an intracellular serine/threonine kinase, is implicated in cell growth and survival, cell-cycle progression, tumor angiogenesis, and cell apoptosis. Recent studies showed that the expression and activity of ILK increased significantly in many types of solid tumors. However, the exact molecular mechanism of ILK underlie tumor has not been fully ascertained. The purpose of our study was to determine whether knockdown of ILK would inhibit cell growth and induce apoptosis in bladder cancer cells using a plasmid vector based small interfering RNA (siRNA). The experiments showed that knockdown of ILK could remarkably inhibit cell proliferation and growth, regulate cell cycle and induce apoptosis of bladder cancer BIU-87 and EJ cells. We demonstrated that knockdown of ILK inhibited phosphorylation of downstream signaling targets protein kinase B/Akt, glycogen synthase kinase 3-beta (GSK-3ß), and reduced expression of ß-catenin in BIU-87 as well as EJ cells by Western blot and Immunofluorescence analysis. In addition, down-regulation of ILK also could increase expression of Ribonuclease inhibitor (RI), an important acidic cytoplasmic protein with many functions. BALB/C nude mice injected with the BIU-87 cells transfected ILK siRNA showed a significant inhibition of the tumor growth with lighter tumor weight, lower microvessels density and higher apoptosis rate than those in the other two control groups. In conclusion, these results suggest that ILK might be involved in the development of bladder cancer, and could be served as a novel potential therapy target for human bladder cancer. Our study may be of biological and clinical importance.

[Construction of let-7a expression plasmid and its inhibitory effect on k-Ras protein in A549 lung cancer cells].

OBJECTIVE: To elucidate the role of let-7a-mediated gene regulation in the pathogenesis of lung cancer. METHODS: Two template DNA sequences were designed based on hsa-let-7a sequence in miRBase database. The let-7a expression construct and a control plasmid, namely pGenesil-let-7a and pGenesil-control, respectively, were generated by cloning the annealed oligonucleotides into pGenesil-1 and then transfected into A549 cells, which were selected by G418 to establish the lung cancer cell lines stably expressing let-7a-GFP and control-GFP. The living cells were counted by MTT assay and cell growth curves were drawn to analyze the cell proliferation. The k-Ras mRNA level was assessed by semi-quantitative RT-PCR, and the expression of k-Ras protein was determined by Western blotting and immunocytochemistry. RESULTS: The recombinant vectors were verified by sequencing. The cell growth curves indicated that the proliferation of the cells transfected with pGenesil- let-7a were inhibited significantly compared with that of cells transfected with pGenesil-control and A549 cells. Semi- quantitative RT-PCR analysis showed that the levels of k-Ras mRNA almost remained unchanged in cells with or without the treatments. Western blotting and immunocytochemistry demonstrated a significant decrease of k-Ras protein levels in cells transfected with pGenesil-let-7a, but not in cells transfected with pGenesil-control, when compared to A549 cells. CONCLUSION: let-7a over-expression represses the expression of k-Ras protein and significantly inhibits the growth of lung cancer cells.

The let-7a microRNA protects from growth of lung carcinoma by suppression of k-Ras and c-Myc in nude mice.

PURPOSE: Down-regulation of let-7 microRNA (miRNA) plays an important role in the pathogenesis of lung cancer. k-Ras and c-Myc, two key oncogenes in lung cancer, have been found to be targeted by let-7 in vitro. However, the in vivo relevance of these findings is unknown. The aim of the present study is to determine the effect of let-7a, a member of let-7 family, on the growth of lung cancer in vivo and to investigate whether let-7-induced suppression of k-Ras and c-Myc is involved in lung cancer. METHODS: A549-let-7a cell line and A549-control cell line, two stable transfected cell lines over-expressing let-7a and the control miRNA, were established and preserved in our lab. A549, A549-control, and A549-let-7a cells were injected subcutaneously into nude mice, respectively. After 30 days, the mice were killed; the xenografts were excised and weighed. The expression of let-7a in tumor xenografts was assessed by real-time reverse transcription-PCR (RT-PCR). The expression of k-Ras and c-Myc in xenografts were determined by western blot and immunohistochemistry detection. RESULTS: Real-time RT-PCR showed the expression of let-7a was increased significantly in A549-let-7a cells-injected group, compared with A549-control cells-injected group and A549 cells-injected group (P < 0.01). In the xenografts of A549-let-7a cells-injected group, a significant depression in tumor weight (P < 0.05) and significant decrease of k-Ras and c-Myc protein were observed (P < 0.01), compared to A549 cells-injected group and A549-control cells-injected group. CONCLUSION: Overexpression of let-7a can inhibit the growth of lung cancer transplanted subcutaneously in nude mice by suppression of k-Ras and c-Myc.

Effects of Bushen Kangshuai Tang in retrieving oxidative stress-induced reproductive defects in Caenorhabditis elegans.

OBJECTIVE: To explore the function of Bushen Kangshuai Tang (BKT), a compound traditional Chinese herbal medicine, in alleviating oxidative stress-induced reproductive defects in organism nematode Caenorhabditis elegans. METHODS: The L4-larvae were cultured with 25%, 50%, 75%, and 100% of BKT with the final concentration of 0.33 g/mL. Ultraviolet irradiation [20 J/(m(2) x min)], heat-shock (36 degrees centigrade, 2 h), and paraquat treatment (2 mmol/L, 2h) were exerted as the stresses. Reproduction was assayed by the egg number in uterus, brood size, and generation time. RESULTS: Ultraviolet irradiation, heat-shock, and paraquat treatment could significantly reduce egg number in uterus and brood size, increase generation time, and suppress activities of catalase and superoxide dismutase of the treated wild-type N2 nematodes. Administration of BKT did not cause toxic or altered effects on reproduction under wild-type background in C. elegans. However, BKT administration at higher concentrations could not only effectively alleviate the reproductive defects induced by ultraviolet irradiation, heat-shock, and paraquat treatment, but also increase the catalase and superoxide dismutase activities suppressed by ultraviolet irradiation, heat-shock, and paraquat treatment as compared with the control. Moreover, administration of BKT at higher concentrations could largely recover the reproductive defects formed in mev-1 mutant nematodes with elevated oxidative stress. CONCLUSION: Oxidative stress can negatively regulate the reproductive process, and the administration of high concentrations of BKT will largely retrieve the oxidative stress-induced reproductive defects in exposed nematodes.

[Inducement effect of ginsenoside Rg3 on apoptosis of human bladder transitional cell carcinoma cell line EJ].

OBJECTIVE: To explore the effect of Rg3 on inhibiting and inducing apoptosis of bladder cancer cells. METHOD: The bladder cancer cell line EJ was treated with Rg3 of various concentrations. Cell proliferation was measured by MTT assay. Morphological changes of cells were observed by fluorescent staining of Hoechst 33258. Cell cycle and apoptosis rate were analyzed by flow cytometry (FCM). The expression of caspase-3 in cells was detected by immunocytochemistry. DNA ladder was showed by agarose gel electrophoresis. RESULT: Rg3 inhibited proliferation of EJ cells in a manner of concentration-dependent relationship, IC50 of Rg3 in 48 h treatment was 125.5 mg x L(-1) to EJ cells. When treated with 150 mg x L(-1) of Rg3 for 24 h and 48 h, the cells showed apoptotic morphological characteristics including the condensed chromatin, the nuclear fragmentation, the apoptotic body and bright fluorescent granules as well as a higher caspase-3 expression. FCM assay indicated that Rg3 regulated cell cycle and induced apoptosis of EJ cells. When treated for 24 h and 48 h with 75 mg x L(-1) of Rg3 as well as for 48 h with 150 mg x L(-1) of Rg3, the percentages of cells in S phase and G2/M phase were increased, whereas the percentage of cells in G0-G1 was decreased. The apoptosis rates were increased from (1.05 +/- 0.17)% in control group cells to (8.41 +/- 0.98)%, (18.57 +/- 2.20)% and (33.98 +/- 1.64)%, respectively. Remarkable DNA ladders were revealed. The effects showed a manner in dose and time dependent of Rg3. CONCLUSION: The results suggest that ginsenoside Rg3 exerts an inhibiting effect on proliferation of EJ cells by inducing apoptosis.

Antitumor effects of human ribonuclease inhibitor gene transfected on B16 melanoma cells.

Human ribonuclease inhibitor (RI) is a cytoplasmic acidic protein. The experiment demonstrated that it might effectively inhibit tumor-induced angiogenesis and inhibit tumor growth. Ribonuclease inhibitor is constructed almost entirely of leucine-rich repeats, which might be involved in unknown biological effects besides inhibiting RNase A and angiogenin activities. The exact molecular mechanism of antitumor on ribonuclease inhibitor remains unclear so far. In order to further understand the function of ribonuclease inhibitor and investigate the relationship with tumor growth, our study established a transfection of human ribonuclease inhibitor cDNA into the murine B16 cells by the retroviral packaging cell line PA317. The cell line transfected with a stably high expression of ribonuclease inhibitor was identified. We found that the transfected ribonuclease inhibitor could obviously inhibit cell proliferation, regulate cell cycle and induce cell apoptosis in vitro. Mice that were injected with the B16 cells transfected RI cDNA showed a significant inhibition of the tumor growth with lighter tumor weight, lower density of microvessels, longer latent periods, and survival time than those in the other two control groups. In conclusion, the results reveal the novel mechanism that antitumor effect of ribonuclease inhibitor is also associated with inducing apoptosis, regulating cell cycle and inhibiting proliferation besides antiangiogenesis. These results suggest that ribonuclease inhibitor might be a candidate of tumor suppressor gene in some tissues. RI could become a target gene for gene therapy. Our study may be of biological and clinical importance.

Effects of DNA methylation inhibitor on down-regulation of ribonuclease inhibitor expression in cancer cell lines.

BACKGROUND & OBJECTIVE: Human ribonuclease inhibitor (RI) could effectively block angiogenin-induced angiogenesis, and inhibit growth of transplant solid tumors in animals. However, its exact molecular mechanism of antitumor has not been totally ascertained. Many tumor suppressor genes occur loss of expression by aberrant methylation in promoter region. Demethylation, treated with methylation inhibitor 5-aza-2'-deoxycytidine (5-Aza-CdR),can restore the gene expression. To further explore functions of RI, and investigate relationship between RI and tumorigenesis, the study was designed to explore effects of 5-Aza-CdR on expression of RI in cancer cell lines. METHODS: Human breast cancer cell line MCF-7, human gastric cancer cell line BGC-823, human prostate cancer cell line DU-145, and human colon cancer cell line HT-29 were treated with 5-Aza-CdR. Expression of RI was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR), Western blot, immunofluorescence, and immunocytochemistry. RESULTS: Expression of RI significantly elevated by 5-Aza-CdR at both mRNA and protein level in MCF-7, BGC-823, and DU-145 cells (P< 0.01). Compared with control cells, mRNA levels of RI in MCF-7, BGC-823, and DU-145 cells treated with 5-Aza-CdR were increased by percentages of 37.2%, 46.0%, and 32.4%, respectively; protein levels of RI were increased by percentages of 26.4%, 20.9%, and 24.4%, respectively; but no obvious change observed in HT-29 cells. CONCLUSION: RI gene may be involved in tumorigenesis of gastric, prostate, and breast cancer.

[Preparation and purification of the antibody against ribonuclease inhibitor].

AIM: To prepare and purify the antibody against ribonuclease inhibitor(RI). METHODS: RI was extracted from human placenta and purified by affinity chromatography. Rabbits anti-RI antibody was obtained after immunization and then purified through rProtein A Sepharose Fast Flow chromatography column. The characters of the antibody was identified by SDS-PAGE, ELISA and Western blot. RESULTS: An anti-RI antibody was obtained and purified. SDS-PAGE analysis showed that the purified anti-RI antibody has high purity. The results of Western blot and ELISA indicated that anti-RI antibody had high specificity and good stability. CONCLUSION: The anti-RI antibody with high titer, high specificity and good stability has been acquired, which lays the foundation for further research on RI.

[Inhibitory effect of ginsenoside-Rg3 on lung metastasis of mouse melanoma transfected with ribonuclease inhibitor].

OBJECTIVE: To investigate the effect of ginsenoside-Rg3 on lung metastasis of ribonuclease inhibitor (RI) gene-transfected mouse B16 melanoma. METHODS: C57BL/6 mice were iv injected with parental or RI-transfected B16 melanoma cells. Lung metastasis was assessed by the number of surface tumor nodules. Mice were divided into 6 groups. Group I, II and III of mice were given parental, mock-transfected and RI-transfected B16 melanoma cells, respectively while in group IV, V and VI, Rg3 (1.5 mg/kg, iv q.o.d. x 10) was given to mice bearing parental, mock-transfected and RI-transfected B16 melanoma, respectively. Micovessel density (MVD) of the lung metastatic tumor was assessed by immunohistochemical staining of factor VIII-R expression. RESULTS: The number of tumor nodules was significantly decreased in mice injected with RI-transfected B16 melanoma (Gp III, compared to Gp I and II). Rg3 treatment per se could also decrease the number of lung tumor nodules but to a lesser extent (Gp IV and V compared to Gp III). However, Rg3 synergized with RI transfection resulting in most significant inhibition of lung metastasis (Gp VI). Mice in Gp I and II died within 26 days of the experiment, whereas all the mice in Gp VI were alive during the observation period of one and one half month. MVD was significantly decreased in the lung tumor nodules in mice injected with RI-transfected B16 melanoma. It was further decreased when additional Rg3 was given (Gp VI). CONCLUSION: Transfection of ribonuclease inhibitor gene significantly reduces the metastatic potential of B16 melanoma. Ginsenoside-Rg3 has a synergistic effect.