Cancer cell sensitivity to bortezomib is associated with survivin expression and p53 status but not cancer cell types

Background

Survivin is known playing a role in drug resistance. However, its role in bortezomib-mediated inhibition of growth and induction of apoptosis is unclear. There are conflicting reports for the effect of bortezomib on survivin expression, which lacks of a plausible explanation. Methods: In this study, we tested cancer cells with both p53 wild type and mutant/null background for the relationship of bortezomib resistance with survivin expression and p53 status using MTT assay, flow cytometry, DNA fragmentation, caspase activation, western blots and RNAi technology.

Results

We found that cancer cells with wild type p53 show a low level expression of survivin and are sensitive to treatment with bortezomib, while cancer cells with a mutant or null p53 show a high level expression of survivin and are resistant to bortezomib-mediated apoptosis induction. However, silencing of survivin expression utilizing survivin mRNA-specific siRNA/shRNA in p53 mutant or null cells sensitized cancer cells to bortezomib mediated apoptosis induction, suggesting a role for survivin in bortezomib resistance. We further noted that modulation of survivin expression by bortezomib is dependent on p53 status but independent of cancer cell types. In cancer cells with mutated p53 or p53 null, bortezomib appears to induce survivin expression, while in cancer cells with wild type p53, bortezomib downregulates or shows no significant effect on survivin expression, which is dependent on the drug concentration, cell line and exposure time.

Conclusions

Our findings, for the first time, unify the current inconsistent findings for bortezomib treatment and survivin expression, and linked the effect of bortezomib on survivin expression, apoptosis induction and bortezomib resistance in the relationship with p53 status, which is independent of cancer cell types. Further mechanistic studies along with this line may impact the optimal clinical application of bortezomib in solid cancer therapeutics.     

Severe reversible cardiac failure after bortezomib treatment combined with chemotherapy in a non-small cell lung cancer patient: a case report

Background

Bortezomib (Velcade^®), a dipeptide boronate proteasome inhibitor, is a novel anti-cancer agent registered for multiple myeloma (MM). It has also shown promising clinical activity in non-small cell lung cancer (NSCLC). Clinical experience with bortezomib so far indicates that overall incidence of cardiac failure associated with bortezomib therapy remains incidental. Nevertheless, acute development or exacerbation of congestive cardiac failure has been associated with bortezomib treatment.

Case presentation

We present here a case of severe, but reversible, congestive cardiac failure in a lung cancer patient who had no prior cardiac history, after receiving an experimental treatment of bortezomib combined with chemotherapy. Elevated levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP), as retrospectively measured in archived serum samples, were suggestive of pre-existent (sub-clinical) left ventricular dysfunction.

Conclusion

Based on literature, we hypothesize that baseline presence of sub clinical cardiomyopathy, characterized by a dysregulation of the ubiquitin-proteasome system, could have predisposed this patient for a cardiac side effect induced by systemic proteasome inhibition. Patients with heart disease or risk factors for it should be closely monitored when being submitted to treatment with proteasome inhibition therapy such as bortezomib. Caution is therefore warranted in lung cancer patients who often present with cardiac comorbidities.     

Experimental study on the mechanism of reversal of leukemia multidrug resistance by proteasome inhibitor bortezomib

Objective  

In this study, we applied multidrug resistant leukemia cell line expressing mdr1-mRNA to observe changes in mdr1-mRNA, the P-gp, cell cycle and apoptosis before and after bortezomib was used, in order to explore the mechanism of reversal of leukemia multidrug resistance by the proteasome inhibitor bortezomib.     

The interaction of bortezomib with multidrug transporters: implications for therapeutic applications in advanced multiple myeloma and other neoplasias

Purpose

Bortezomib is an important agent in multiple myeloma treatment, but resistance in cell lines and patients has been described. The main mechanisms of resistance described in cancer fall into one of two categories, pharmacokinetic resistance (PK), e.g. over expression of drug efflux pumps and pharmacodynamic resistance, e.g. apoptosis resistance or altered survival pathways, where the agent reaches an appropriate concentration, but this fails to propagate an appropriate cell death response. Of the known pump mechanisms, P-glycoprotein (P-gp) is the best studied and considered to be the most important in contributing to general PK drug resistance. Resistance to bortezomib is multifactorial and there are conflicting indications that cellular overexpression of P-gp may contribute to resistance agent. Hence, better characterization of the interactions of this drug with classical resistance mechanisms should identify improved treatment applications.

Methods

Cell lines with different P-gp expression levels were used to determine the relationship between bortezomib and P-gp. Coculture system with stromal cells was used to determine the effect of the local microenvironment on the bortezomib–elacridar combination. To further assess P-gp function, intracellular accumulation of P-gp probe rhodamine-123 was utilised.

Results

In the present study, we show that bortezomib is a substrate for P-gp, but not for the other drug efflux transporters. Bortezomib activity is affected by P-gp expression and conversely, the expression of P-gp affect bortezomib’s ability to act as a P-gp substrate. The local microenvironment did not alter the cellular response to bortezomib. We also demonstrate that bortezomib directly affects the expression and function of P-gp.

Conclusions

Our findings strongly support a role for P-gp in bortezomib resistance and, therefore, suggest that combination of a P-gp inhibitor and bortezomib in P-gp positive myeloma would be a reasonable treatment combination to extend efficacy of this important drug.     

Role of oxidative stress and intracellular glutathione in the sensitivity to apoptosis induced by proteasome inhibitor in thyroid cancer cells

Background  

The proteasome inhibitor bortezomib has shown impressive clinical activity alone and in combination with conventional and other novel agents for the treatment of multiple myeloma (MM) and some solid cancers. Although bortezomib is known to be a selective proteasome inhibitor, the downstream mechanisms of cytotoxicity and drug resistance are poorly understood.     

Reversion of multidrug-resistance by proteasome inhibitor bortezomib in K562/DNR cell line

Objective:To observe the reversion of multi-drug resistance by proteasome inhibitor bortezomib in K562/DNR cell line and to analyze the possible mechanism of reversion of multidrug-resistance.Methods:MTT method was used to determine the drug resistance of K562/DNR cells and the cellular toxicity of bortezomib.K562/DNR cells were cultured for 12 hours,24 hours and 36 hours with 100 μg/ml DNR only or plus 4 μg/L bortezomib.The expressions of NF-κB,IκB and P-gp of K562/DNR were detected with Western blot method,the activity of NF-κB was tested by ELISA method and the apoptosis rate was observed in each group respectively.Results:The IC50 of DNR on cells of K562/S and K562/DNR groups were 1.16 μg/ml and 50.43 μg/mL,respectively.The drug-resistant fold was 43.47.The IC10 of PS-341 on Cell strain K562/DNR was 4 μg/L.Therefore,4 μg/L was selected as the concentration for PS-341 to reverse drug-resistance in this study.DNR induced down-regulation of IκB expression,up-regulation of NF-κB and P-gp expression.After treatment with PS-341,a proteasome inhibitor,the IκB degradation was inhibited,IκB expression increased,NF-κB and P-gp expression decreased in a time dependent manner.Compared to DNR group,the NF-κB p65 activity of DNR+PS-341 group was decreased.Compared to corresponding DNR group,DNR induced apoptosis rate increases after addition of PS-341 in a time dependent manner.Conclusion:Proteasome inhibitor bortezomib can convert the leukemia cell drug resistance.The mechanism may be that bortezomib decreases the degradation of IκB and the expression of NF-κB and P-gp,therefore induces the apoptosis of multi-drug resistant cells.     

Efficacy of plasma vascular endothelial growth factor in monitoring first-line chemotherapy in patients with advanced non-small cell lung cancer

Background  

Along with the development of new cancer therapeutics, more effective tools for the estimation of response to therapy and prediction of disease progression are required for the better management of inoperable cancer patients.     

Bortezomib induces protective autophagy through AMP-activated protein kinase activation in cultured pancreatic and colorectal cancer cells

Background

Bortezomib, a selective and potent inhibitor of the proteasome, has demonstrated broad anti-tumor activities in many malignancies. In the current study, we aimed to understand the potential resistance factor of bortezomib in cultured pancreatic and colorectal cancer cells.

Results

We observed that bortezomib-induced protective autophagy in cultured PANC-1 pancreatic cancer cells and HT-29 colorectal cancer cells. Inhibition of autophagy by 3-methyladenine (3-MA) and chloroquine enhanced bortezomib-induced apoptosis and cytotoxicity in both PANC-1 and HT-29 cells. Activation of AMP-activated protein kinase (AMPK) was required for bortezomib-induced autophagy induction in PANC-1 and HT-29 cells, and AMPK inhibition by its inhibitor compound C (CC) or RNAi-depletion suppressed bortezomib-induced autophagy, while dramatically enhancing cancer cell apoptosis/cytotoxicity. Meanwhile, significant AMPK activation and autophagy induction were observed after bortezomib stimulation in primary cultured pancreatic cancer cells derived from a patient’s tumor tissue. Both CC and 3-MA facilitated bortezomib-induced cytotoxicity in primary cultured pancreatic cancer cells.

Conclusions

In conclusion, our data here suggest that bortezomib induces protective autophagy in pancreatic and colorectal cancer cells through activating AMPK-Ulk1 signalings. AMPK or autophagy inhibitors could be developed as an adjunct or chemo-sensitizer for bortezomib.     

Age-stratified phase I trial of a combination of bortezomib,gemcitabine, and liposomal doxorubicin in patients with advanced malignancies

Background  

Preclinical data suggest synergistic activity of bortezomib, gemcitabine, and liposomal doxorubicin. Because tolerance to therapy may be attenuated in elderly patients, we performed an age-stratified phase I trial of this combination.     

The efficacy and safety of bortezomib and dexamethasone as a maintenance therapy in patients with advanced multiple myeloma who are responsive to salvage bortezomib-containing regimens

BACKGROUND:

Although treatment for multiple myeloma (MM) has considerably improved in the past decade, MM continues to be an incurable hematological malignancy that causes most patients to eventually relapse and die from their illness. Thus, the identification of effective salvage strategies remains a priority.

METHODS:

In this trial, the authors evaluated the safety and efficacy of bortezomib and dexamethasone [V: on days 1 and 15 (1.3 mg/mq); D: on days 1‐2 and 15‐16, every 28‐day cycle until progression (20 mg/d)] as maintenance therapy (MT) in patients with advanced MM who responded to salvage therapy that used a bortezomib‐containing regimen.

RESULTS:

Forty‐nine MM patients were enrolled in this study between October of 2004 and April of 2008. All patients who were included in this study were responsive to a prior salvage therapy with bortezomib and had a measurable disease. The bortezomib and dexamethasone MT improved the quality of responses to complete remission in 4 patients and very good partial response in 3 patients. In addition, 10 patients experienced at least a 50% improvement in their symptoms. The median time to progression (TTP) was 16 months with a progression‐free survival of 61% after 1 year. The overall response after 1 year was 76%, and the cumulative incidence of death due to disease progression, which was adjusted for competitive risk events, was 14%. Non‐dose‐limiting toxicities included neuropathy (predominantly grade 1), herpes zoster reactivation, pneumonia, and gastrointestinal affections (constipation and diarrhea). Three patients developed grade 2 neuropathy, which required a bortezomib dose reduction to 1.0 mg/mq. No grade 3 or 4 toxicities were recorded.

CONCLUSIONS:

The use of bortezomib and dexamethasone as MT in advanced MM was effective and well tolerated. The twice‐monthly bortezomib infusion appeared to reduce the incidence of grade 3 and 4 neuropathies in comparison to similar experiences in other settings. Cancer 2011. © 2010 American Cancer Society.     

Indole-3-carbinol synergistically sensitises ovarian cancer cells to bortezomib treatment

Background:

Bortezomib is a proteasome inhibitor with minimal clinical activity as a monotherapy in solid tumours, but its combination with other targeted therapies is being actively investigated as a way to increase its anticarcinogenic properties. Here, we evaluate the therapeutic potential of co-treatment with bortezomib and indole-3-carbinol (I3C), a natural compound found in cruciferous vegetables, in human ovarian cancer.

Methods:

We examined the effects of I3C, bortezomib and cisplatin in several human ovarian cancer cell lines. Synergy was determined using proliferation assays and isobologram analysis. Cell cycle and apoptotic effects were assessed by flow cytometry. The mechanism of I3C and bortezomib action was determined by RNA microarray studies, quantitative RT–PCR and western blotting. Antitumour activity of I3C and bortezomib was evaluated using an OVCAR5 xenograft mouse model.

Results:

I3C sensitised ovarian cancer cell lines to bortezomib treatment through potent synergistic mechanisms. Combination treatment with bortezomib and I3C led to profound cell cycle arrest and apoptosis as well as disruptions to multiple pathways, including those regulating endoplasmic reticulum stress, cytoskeleton, chemoresistance and carcinogen metabolism. Moreover, I3C and bortezomib co-treatment sensitised ovarian cancer cells to the standard chemotherapeutic agents, cisplatin and carboplatin. Importantly, in vivo studies demonstrated that co-treatment with I3C and bortezomib significantly inhibited tumour growth and reduced tumour weight compared with either drug alone.

Conclusion:

Together, these data provide a novel rationale for the clinical application of I3C and bortezomib in the treatment of ovarian cancer.     

High estrogen receptor expression and low Ki67 expression are associated with improved time to progression during first-line endocrine therapy with aromatase inhibitors in breast cancer

Background  

Aromatase inhibitors have played a central role in endocrine therapy for estrogen receptor (ER)-positive breast cancer in postmenopausal women. However, many breast cancer patients with tumors expressing ER are unresponsive to aromatase inhibitors, and all patients with advanced disease eventually develop resistance to the therapy.     

Revisiting Clinical Trials Using EGFR Inhibitor-Based Regimens in Patients with Advanced Non-Small Cell Lung Cancer: A Retrospective Analysis of an MD Anderson Cancer Center Phase I Population

Purpose

Single-agent EGFR inhibitor therapy is effective mainly in patients with lung cancer and EGFR mutations. Treating patients who develop resistance, or who are insensitive from the outset, often because of resistant mutations, other aberrations or the lack of an EGFR mutation, probably requires rational combinations. We therefore investigated the outcome of EGFR inhibitor-based combination regimens in patients with heavily-pretreated non-small cell lung cancer (NSCLC) referred to a Phase I Clinic.

Methods

We reviewed the electronic records of patients with NSCLC treated with an EGFR inhibitor-based combination regimen: erlotinib and cetuximab; erlotinib, cetuximab and bevacizumab; erlotinib and dasatinib; erlotinib and bortezomib; or cetuximab and sirolimus.

Results

EGFR mutations were detected in 16% of patients (21/131). EGFR inhibitor-based combination regimens were administered to 15 patients with EGFR-mutant NSCLC and 24 with EGFR wild-type disease. Stable disease (SD) ≥6 months/partial remission (PR) was attained in 20% of EGFR-mutant patients (3/15; two with sensitive mutations and secondary resistance to prior erlotinib, and one with a resistant mutation), as well as 26% of evaluable patients (5/19) with wild-type disease. One of three evaluable patients with squamous cell histology achieved SD for 26.5 months (EGFR wild-type, TP53-mutant, regimen=erlotinib, cetuximab and bevacizumab).

Conclusions

Eight of 34 evaluable patients (24%) with advanced, refractory NSCLC evaluable for response achieved SD ≥6 months/PR (PR=3; SD ≥6 months=5) on EGFR inhibitor-based combination regimens (erlotinib, cetuximab; erlotinib, cetuximab and bevacizumab; and, erlotinib, bortezomib), including patients with secondary resistance to single-agent EGFR inhibitors, resistant mutations, wild-type disease, and, squamous histology.     

Acyclovir to prevent reactivation of varicella zoster virus (herpes zoster) in multiple myeloma patients receiving bortezomib therapy

BACKGROUND:

Humoral‐mediated as well as cell‐mediated immunity is compromised in myeloma patients receiving treatment. Immunocompromised patients are at risk of developing herpes zoster. There is evidence from clinical trials that bortezomib therapy is associated with a significant risk of herpes zoster. It is the authors' clinical policy to administer long‐term acyclovir prophylactically to all symptomatic myeloma patients.

METHODS:

A retrospective review of the records of 125 myeloma patients who were treated with bortezomib and who also received routine acyclovir prophylaxis at the dose of 400 mg daily in >80% of patients was undertaken. Alternatives, used in <20% of patients, were 200 mg of acyclovir, 250/500 mg of valacyclovir, or 500 mg of famciclovir administered daily. This was accompanied by patient education regarding the importance of compliance with these prophylactic medications.

RESULTS:

The duration of bortezomib therapy was 1 to 164 weeks (median, 16 weeks). The total duration of exposure to bortezomib was 4150 weeks (80 patient‐years). Except for the occasional missed dose, the self‐reported compliance with antiviral prophylaxis was 100%. Not a single episode of herpes zoster was reported during this period. No adverse effects were noted that could be definitely attributed to acyclovir, valacyclovir, or famciclovir.

CONCLUSIONS:

Daily acyclovir (or a suitable alternative) appears to be effective at preventing herpes zoster virus in patients with myeloma who are receiving bortezomib, with or without corticosteroids. Cancer 2009. © 2008 American Cancer Society.     

Potential predictive markers of chemotherapy resistance in stage III ovarian serous carcinomas

Background  

Chemotherapy resistance remains a major obstacle in the treatment of women with ovarian cancer. Establishing predictive markers of chemoresponse would help to individualize therapy and improve survival of ovarian cancer patients. Chemotherapy resistance in ovarian cancer has been studied thoroughly and several non-overlapping single genes, gene profiles and copy number alterations have been suggested as potential markers. The objective of this study was to explore genetic alterations behind chemotherapy resistance in ovarian cancer with the ultimate aim to find potential predictive markers.     

卵巢切除联合依西美坦治疗绝经前激素受体阳性晚期难治性乳腺癌

Objective  

Taking tamoxifen orally is the main endocrine therapy of the premenopausal breast cancer with positive hormone receptor, but numerous patients developed to be advanced refractory breast cancer because of drug resistance. Our study investigated a role of the combination of bilateral oophorectomy and exemestane in the management of advanced refractory breast cancer.     

Overexpression of the ATP binding cassette gene ABCA1 determines resistance to Curcumin in M14 melanoma cells

Background  

Curcumin induces apoptosis in many cancer cells and it reduces xenograft growth and the formation of lung metastases in nude mice. Moreover, the plant derived polyphenol has been reported to be able to overcome drug resistance to classical chemotherapy. These features render the drug a promising candidate for tumor therapy especially for cancers known for their high rates concerning therapy resistance like melanoma.     

Effect of bortezomib on human neuroblastoma: analysis of molecular mechanisms involved in cytotoxicity

Background  

Bortezomib, a specific and selective inhibitor of the 26S proteasome with antitumor activity against a wide range of malignancies, has been approved for the treatment of relapsed or refractory multiple myeloma and other cancers. Recently, bortezomib has been identified as an effective inhibitor of neuroblastoma cell growth and angiogenesis.     

MP470, a novel receptor tyrosine kinase inhibitor, in combination with Erlotinib inhibits the HER family/PI3K/Akt pathway and tumor growth in prostate cancer

Background  

Prostate cancer is a common disease in men and at present there is no effective therapy available due to its recurrence despite androgen deprivation therapy. The epidermal growth factor receptor family (EGFR/HER1, HER2/neu and HER3)/PI3K/Akt signaling axis has been implicated in prostate cancer development and progression. However, Erlotinib, an EGFR tyrosine kinase inhibitor, has less effect on proliferation and apoptosis in prostate cancer cell lines. In this study, we evaluate whether MP470, a novel receptor tyrosine kinase inhibitor alone or in combination with Erlotinib has inhibitory effect on prostate cancer in vitro and in vivo.     

Bortezomib-induced apoptosis in cultured pancreatic cancer cells is associated with ceramide production

Purpose

The proteasome inhibitor bortezomib (PS-341) has displayed significant efficiency against pancreatic cancer cells. However, the underlying mechanisms are not fully understood. Here, we tested if ceramide production was involved in the bortezomib’s effect.

Methods

Two transformed pancreatic cancer cell lines (PANC-1 and Mia) and the primary pancreatic cancer cells were used. Cell death was analyzed by MTT viability assay and trypan blue staining. Cell apoptosis was analyzed by Histone DNA-ELISA assay and Annexin V FACS. Western blots were used to test signal protein changes. The cellular ceramide level after bortezomib treatment was also determined.

Results

In cultured pancreatic cancer cells, bortezomib increased cellular ceramide production to promote cell apoptosis. The ceramide de novo synthase inhibitor fumonisin B1 (F-B1) suppressed bortezomib-induced ceramide production and apoptosis, while exogenously added C6-ceramide facilitated bortezomib-induced pancreatic cancer cell death. Meanwhile, 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), the inhibitor of glucosylceramide synthetase as well as the sphingosine kinase 1 inhibitors (SKI-II and SKI-IV), facilitated bortezomib-induced ceramide production and subsequent cell apoptosis. Further, bortezomib-induced pro-apoptotic c-Jun N-terminal kinase (JNK) activation was also associated with ceramide production. JNK activation by bortezomib was suppressed by F-B1, but was enhanced by SKI-II and PDMP in pancreatic cancer cells. Finally, C6-ceramide, SKI-II, and PDMP dramatically enhanced bortezomib-induced cytotoxicity in primary cultured pancreatic cancer cells.

Conclusions

We found that bortezomib-induced apoptosis was associated with ceramide production in primary and transformed pancreatic cancer cells.