Breast cancer is the leading cause of cancer-related deaths in women worldwide,with Hormone Receptor(HR)+being the predominant subtype.Tamoxifen(TAM)serves as the primary treatment for HR+breast cancer.However,drug re...Breast cancer is the leading cause of cancer-related deaths in women worldwide,with Hormone Receptor(HR)+being the predominant subtype.Tamoxifen(TAM)serves as the primary treatment for HR+breast cancer.However,drug resistance often leads to recurrence,underscoring the need to develop new therapies to enhance patient quality of life and reduce recurrence rates.Artemisinin(ART)has demonstrated efficacy in inhibiting the growth of drug-resistant cells,positioning art as a viable option for counteracting endocrine resistance.This study explored the interaction between artemisinin and tamoxifen through a combined approach of bioinformatics analysis and experimental validation.Five characterized genes(ar,cdkn1a,erbb2,esr1,hsp90aa1)and seven drug-disease crossover genes(cyp2e1,rorc,mapk10,glp1r,egfr,pgr,mgll)were identified using WGCNA crossover analysis.Subsequent functional enrichment analyses were conducted.Our findings confirm a significant correlation between key cluster gene expression and immune cell infiltration in tamoxifen-resistant and-sensitized patients.scRNA-seq analysis revealed high expression of key cluster genes in epithelial cells,suggesting artemisinin’s specific impact on tumor cells in estrogen receptor(ER)-positive BC tissues.Molecular target docking and in vitro experiments with artemisinin on LCC9 cells demonstrated a reversal effect in reducing migratory and drug resistance of drug-resistant cells by modulating relevant drug resistance genes.These results indicate that artemisinin could potentially reverse tamoxifen resistance in ER-positive breast cancer.展开更多
The side effects of tamoxifen are generally mild, including the effect on lipoprotein metabolism. However, there are few cases of severe tamoxifen induced hypertriglyceridemia. Hypertriglyceridemia is a marked risk fa...The side effects of tamoxifen are generally mild, including the effect on lipoprotein metabolism. However, there are few cases of severe tamoxifen induced hypertriglyceridemia. Hypertriglyceridemia is a marked risk factor for acute pancreatitis and approximately 2% to 5% of cases of acute pancreatitis are related to drugs. We report on tamoxifen-induced hypertriglyceridemia and acute pancreatitis in a 40 years old woman with type 2 diabetes mellitus occurred by dexamethasone. She was treated with insulin infusion and fenofibrate, and goserelin acetate was started instead of tamoxifen after discharge from the hospital. Also, probable pathogenic hypotheses about the correlation between tamoxifen and dexamethasone induced type 2 diabetes mellitus on severe acute pancreatitis are provided. Clinicians should take care of risks of severe acute pancreatitis on using tamoxifen, especially for patients with dexamethasone induced diabetes mellitus. These individuals should undergo pre-post tamoxifen lipid screening and careful history taking of drugs, including dexamethasone.展开更多
Spinal cord injury （SCI） is a devastating condition that produces significant changes in the life- style of patients. Many molecular and cellular events are triggered after the initial physical impact to the cord. T...Spinal cord injury （SCI） is a devastating condition that produces significant changes in the life- style of patients. Many molecular and cellular events are triggered after the initial physical impact to the cord. Two major phases have been described in the field of SCI： an acute phase and late phase. Most of the therapeutic strategies are focused on the late phase because this provides an opportunity to target cellular events like apoptosis, demyelination, scar formation and axonal outgrowth. In this mini-review, we will focus on two agents （tamoxifen and a Src kinase family inhibitor known as PP2） that have been shown in our laboratory to produce neuroprotective （increase cell survival） and/or regenerative （axonal outgrowth） actions. The animal model used in our laboratory is adult female rat （N250 g） with a moderate contusion （12.5 mm） to the spinal cord at the T10 level, using the MASCIS impactor device. Tamoxifen or PP2 was administered by implantation of a 15 mg pellet （Innovative Research of America, Sarasota, FL, USA） or by intraperitoneal injections （1.5 mg/kg, every 3 days）, respectively, to produce a long-term effect （28 days）. Tamoxifen and the Src kinase inhibitor, PP2, are drugs that in rats with a moderate spinal cord injury promote functional locomotor recovery, increase spared white matter tissue, and stimulate axonal outgrowth. Moreover, tamoxifen reduces the formation of reactive oxygen species. Therefore, these drugs are possible therapeutic agents that have a neuroprotective/regen- erative activity in vertebrates with SCI.展开更多
AIM: To investigate the effect of tamoxifen (TAM) on multidrug resistance (MDR) of colorectal carcinoma in vivo and its relationship with estrogen receptor (ER). METHODS: Multidrug resistance was determined by means o...AIM: To investigate the effect of tamoxifen (TAM) on multidrug resistance (MDR) of colorectal carcinoma in vivo and its relationship with estrogen receptor (ER). METHODS: Multidrug resistance was determined by means of semi-quantitative retro-transcription polymerase chain reaction (RT-PCR) to test mdr1 gene mRNA and ER expression was studied by immunohistochemistry. Tumor tissues from three cases of human colon carcinoma, which had mdr1(+)/ER(+),mdr1(+)/ER(-), mdr1(-) expressions, were planted subcutaneously in the neck of nude mice to establish three xenograft models. These models were subdivided into four subgroups randomly: Doxorubicin (DOX)-treated group, TAM-treated group, DOX and TAM group and control group. The dimensions of these xenografts were measured after each course of treatment and the xenografts were removed at the end of the experiments for measurements of weight and the variation of mdr1 mRNA level with RT-PCR. In each course, TAM [15 mg/(kg/d)] was administrated orally per day in the first seven days and DOX (3.6 mg/kg) was injected peritoneally on the first day. Data was evaluated by q and t tests. RESULTS: In the animal models with mdr1(-) tumor, the weights and volumes of the planted tumor in DOX group [(39.1±2.29) mg, (31.44±1.61) mm3] and TAM and DOX group [(38.72±2.56) mg, (31.31v1.74) mm3], which were lesser than that of control group [(45.48±3.92) mg, (36.42±2.77) mm3, P= 0.037, P= 0.016 respectively] significantly. In the animal models with mdr1(+)/ER(+) tumor, the weights and volumes of planted tumor were not affected by DOX or TAM treatment; however, in TAM and DOX group [(425.5±28.58) mg, (340.35±22.28) mm3], they were significantly less than that of control group [(634.23±119.41) mg, (507.45±93.34) mm3, P= 0.022, P = 0.045 respectively], which are similar to that in the models with mdr1(+)/ER(-) tumor. No significant changes were found in the expressive level of mdr1 mRNA following these treatments. CONCLUSION: The expression of mdr1 gene corresponds to the sensitivity of colon cancer to anti-tumor drugs in vivo. TAM can reverse the MDR of colorectal carcinoma in nude mice, which is independent of the expression of ER; however, no change was observed in the expressive level of mdr1 mRNA.展开更多
Aim: To identify the antifertility effect of intermittent oral administration of tamoxifen in male rat. Methods:Tamoxifen was administered orally at a dose of 0.4 mg·kg^(-1)·d^(-1) with an intermittent regim...Aim: To identify the antifertility effect of intermittent oral administration of tamoxifen in male rat. Methods:Tamoxifen was administered orally at a dose of 0.4 mg·kg^(-1)·d^(-1) with an intermittent regime for 120 days. Treatedand control rats were mated with cycling female rats on days 60, 90 and 120 of treatment. The mated males were sacri-ficed and the weights of reproductive organs were recorded, and the serum levels of LH, FSH, testosterone and estradi-ol estimated by radioimmunoassay. In the female rats, the numbers of implantation sites, corpora lutea, and numbersof normal and resorbed foetuses were recorded on d 21 of gestation. The potency, fecundity, fertility index, litter sizeand post-implantation loss were then calculated. Results; The fecundity of male rats was completely suppressed bytamoxifen while the potency was maintained at the control level. The fertility index was significantly decreased. No vi-able litters were sired. Post implantation loss, indicative of non-viable embryos, was observed but was not significantlyincreased above the control level. The weights of the testes, epididymides, ventral prostate and seminal vesicles weresignificantly reduced. The blood LH and testosterone levels were significantly decreased, but not FSH and estradiol.Conclusion; Intermittent oral tamoxifen administration completely suppressed the fecundity of adult male rats withreserved potency.展开更多
We sought to determine whether STAT3 mediated tamoxifen resistance of breast cancer stem cells in vitro.The capacities for mammosphere formation and STAT3 expression of CD44＋CD24-/low MCF-7 and MCF-7 were observed.Th...We sought to determine whether STAT3 mediated tamoxifen resistance of breast cancer stem cells in vitro.The capacities for mammosphere formation and STAT3 expression of CD44＋CD24-/low MCF-7 and MCF-7 were observed.The CD44＋CD24-/low subpopulation ratio and its sensitivity to adriamycin were analyzed in MCF-7 and TAM resistant（TAM-R） cells.Cell cycle,apoptosis,STAT3 and phospho-STAT3 changes were observed af-ter treatment with tamoxifen.Small interference RNA-mediated knockdown of STAT3 in TAM-R cells was also performed.CD44＋CD24-/low MCF-7 showed higher capacities for mammosphere formation and STAT3 expression than total MCF-7.The CD44＋CD24-/low subpopulation was also upregulated in TAM-R cells with less sensitivity to adriamycin than MCF-7.Cell cycle changes,anti-apoptotic effects and STAT3 changes were also found.Mean-while,the knock-down of STAT3 in TAM-R resulted in an increase in sensitivity to tamoxifen.It is concluded that STAT3 plays an essential role in breast cancer stem cells,which correlated with tamoxifen resistance.展开更多
基金supported by the National Natural Science Foundation of China(81973839)High Level Chinese Medical Hospital Promotion Project-Special Project on Formulation R&D and New Drug Translation for Medical Institutions(HLCMHPP2023037)Upgrading the Development and Promotion of about 30 Integrated Chinese and Western Medicine Diagnosis and Treatment Programs(Guidelines for the Diagnosis and Treatment of Breast Cancer with the Combination of Traditional Chinese Medicine and Western Medicine)(ZYZB-2022-798).
文摘Breast cancer is the leading cause of cancer-related deaths in women worldwide,with Hormone Receptor(HR)+being the predominant subtype.Tamoxifen(TAM)serves as the primary treatment for HR+breast cancer.However,drug resistance often leads to recurrence,underscoring the need to develop new therapies to enhance patient quality of life and reduce recurrence rates.Artemisinin(ART)has demonstrated efficacy in inhibiting the growth of drug-resistant cells,positioning art as a viable option for counteracting endocrine resistance.This study explored the interaction between artemisinin and tamoxifen through a combined approach of bioinformatics analysis and experimental validation.Five characterized genes(ar,cdkn1a,erbb2,esr1,hsp90aa1)and seven drug-disease crossover genes(cyp2e1,rorc,mapk10,glp1r,egfr,pgr,mgll)were identified using WGCNA crossover analysis.Subsequent functional enrichment analyses were conducted.Our findings confirm a significant correlation between key cluster gene expression and immune cell infiltration in tamoxifen-resistant and-sensitized patients.scRNA-seq analysis revealed high expression of key cluster genes in epithelial cells,suggesting artemisinin’s specific impact on tumor cells in estrogen receptor(ER)-positive BC tissues.Molecular target docking and in vitro experiments with artemisinin on LCC9 cells demonstrated a reversal effect in reducing migratory and drug resistance of drug-resistant cells by modulating relevant drug resistance genes.These results indicate that artemisinin could potentially reverse tamoxifen resistance in ER-positive breast cancer.
文摘The side effects of tamoxifen are generally mild, including the effect on lipoprotein metabolism. However, there are few cases of severe tamoxifen induced hypertriglyceridemia. Hypertriglyceridemia is a marked risk factor for acute pancreatitis and approximately 2% to 5% of cases of acute pancreatitis are related to drugs. We report on tamoxifen-induced hypertriglyceridemia and acute pancreatitis in a 40 years old woman with type 2 diabetes mellitus occurred by dexamethasone. She was treated with insulin infusion and fenofibrate, and goserelin acetate was started instead of tamoxifen after discharge from the hospital. Also, probable pathogenic hypotheses about the correlation between tamoxifen and dexamethasone induced type 2 diabetes mellitus on severe acute pancreatitis are provided. Clinicians should take care of risks of severe acute pancreatitis on using tamoxifen, especially for patients with dexamethasone induced diabetes mellitus. These individuals should undergo pre-post tamoxifen lipid screening and careful history taking of drugs, including dexamethasone.
基金partially supported by the MBRS-RISE Program(R25 GM061838)COBRE(5P20-GM103642)
文摘Spinal cord injury （SCI） is a devastating condition that produces significant changes in the life- style of patients. Many molecular and cellular events are triggered after the initial physical impact to the cord. Two major phases have been described in the field of SCI： an acute phase and late phase. Most of the therapeutic strategies are focused on the late phase because this provides an opportunity to target cellular events like apoptosis, demyelination, scar formation and axonal outgrowth. In this mini-review, we will focus on two agents （tamoxifen and a Src kinase family inhibitor known as PP2） that have been shown in our laboratory to produce neuroprotective （increase cell survival） and/or regenerative （axonal outgrowth） actions. The animal model used in our laboratory is adult female rat （N250 g） with a moderate contusion （12.5 mm） to the spinal cord at the T10 level, using the MASCIS impactor device. Tamoxifen or PP2 was administered by implantation of a 15 mg pellet （Innovative Research of America, Sarasota, FL, USA） or by intraperitoneal injections （1.5 mg/kg, every 3 days）, respectively, to produce a long-term effect （28 days）. Tamoxifen and the Src kinase inhibitor, PP2, are drugs that in rats with a moderate spinal cord injury promote functional locomotor recovery, increase spared white matter tissue, and stimulate axonal outgrowth. Moreover, tamoxifen reduces the formation of reactive oxygen species. Therefore, these drugs are possible therapeutic agents that have a neuroprotective/regen- erative activity in vertebrates with SCI.
基金Supported by Scientific Foundation of Education Committee of Jiangsu Province. No.96039
文摘AIM: To investigate the effect of tamoxifen (TAM) on multidrug resistance (MDR) of colorectal carcinoma in vivo and its relationship with estrogen receptor (ER). METHODS: Multidrug resistance was determined by means of semi-quantitative retro-transcription polymerase chain reaction (RT-PCR) to test mdr1 gene mRNA and ER expression was studied by immunohistochemistry. Tumor tissues from three cases of human colon carcinoma, which had mdr1(+)/ER(+),mdr1(+)/ER(-), mdr1(-) expressions, were planted subcutaneously in the neck of nude mice to establish three xenograft models. These models were subdivided into four subgroups randomly: Doxorubicin (DOX)-treated group, TAM-treated group, DOX and TAM group and control group. The dimensions of these xenografts were measured after each course of treatment and the xenografts were removed at the end of the experiments for measurements of weight and the variation of mdr1 mRNA level with RT-PCR. In each course, TAM [15 mg/(kg/d)] was administrated orally per day in the first seven days and DOX (3.6 mg/kg) was injected peritoneally on the first day. Data was evaluated by q and t tests. RESULTS: In the animal models with mdr1(-) tumor, the weights and volumes of the planted tumor in DOX group [(39.1±2.29) mg, (31.44±1.61) mm3] and TAM and DOX group [(38.72±2.56) mg, (31.31v1.74) mm3], which were lesser than that of control group [(45.48±3.92) mg, (36.42±2.77) mm3, P= 0.037, P= 0.016 respectively] significantly. In the animal models with mdr1(+)/ER(+) tumor, the weights and volumes of planted tumor were not affected by DOX or TAM treatment; however, in TAM and DOX group [(425.5±28.58) mg, (340.35±22.28) mm3], they were significantly less than that of control group [(634.23±119.41) mg, (507.45±93.34) mm3, P= 0.022, P = 0.045 respectively], which are similar to that in the models with mdr1(+)/ER(-) tumor. No significant changes were found in the expressive level of mdr1 mRNA following these treatments. CONCLUSION: The expression of mdr1 gene corresponds to the sensitivity of colon cancer to anti-tumor drugs in vivo. TAM can reverse the MDR of colorectal carcinoma in nude mice, which is independent of the expression of ER; however, no change was observed in the expressive level of mdr1 mRNA.
文摘Aim: To identify the antifertility effect of intermittent oral administration of tamoxifen in male rat. Methods:Tamoxifen was administered orally at a dose of 0.4 mg·kg^(-1)·d^(-1) with an intermittent regime for 120 days. Treatedand control rats were mated with cycling female rats on days 60, 90 and 120 of treatment. The mated males were sacri-ficed and the weights of reproductive organs were recorded, and the serum levels of LH, FSH, testosterone and estradi-ol estimated by radioimmunoassay. In the female rats, the numbers of implantation sites, corpora lutea, and numbersof normal and resorbed foetuses were recorded on d 21 of gestation. The potency, fecundity, fertility index, litter sizeand post-implantation loss were then calculated. Results; The fecundity of male rats was completely suppressed bytamoxifen while the potency was maintained at the control level. The fertility index was significantly decreased. No vi-able litters were sired. Post implantation loss, indicative of non-viable embryos, was observed but was not significantlyincreased above the control level. The weights of the testes, epididymides, ventral prostate and seminal vesicles weresignificantly reduced. The blood LH and testosterone levels were significantly decreased, but not FSH and estradiol.Conclusion; Intermittent oral tamoxifen administration completely suppressed the fecundity of adult male rats withreserved potency.
文摘We sought to determine whether STAT3 mediated tamoxifen resistance of breast cancer stem cells in vitro.The capacities for mammosphere formation and STAT3 expression of CD44＋CD24-/low MCF-7 and MCF-7 were observed.The CD44＋CD24-/low subpopulation ratio and its sensitivity to adriamycin were analyzed in MCF-7 and TAM resistant（TAM-R） cells.Cell cycle,apoptosis,STAT3 and phospho-STAT3 changes were observed af-ter treatment with tamoxifen.Small interference RNA-mediated knockdown of STAT3 in TAM-R cells was also performed.CD44＋CD24-/low MCF-7 showed higher capacities for mammosphere formation and STAT3 expression than total MCF-7.The CD44＋CD24-/low subpopulation was also upregulated in TAM-R cells with less sensitivity to adriamycin than MCF-7.Cell cycle changes,anti-apoptotic effects and STAT3 changes were also found.Mean-while,the knock-down of STAT3 in TAM-R resulted in an increase in sensitivity to tamoxifen.It is concluded that STAT3 plays an essential role in breast cancer stem cells,which correlated with tamoxifen resistance.
