Irinotecan, a key chemotherapeutic drug for metastatic colorectal cancer

Irinotecan hydrochloride is a camptothecin derivative that exerts antitumor activity against a variety of tumors. SN-38 produced in the body by carboxylesterase is the active metabolite of irinotecan. After irinotecan was introduced for the treatment of metastatic colorectal cancer(CRC) at the end of the last century,survival has improved dramatically. Irinotecan is now combined with 5-fluorouracil,oxaliplatin and several molecularly-targeted anticancer drugs,resulting in the extension of overall survival to longer than 30 mo. Severe,occasionally life-threatening toxicity occurs sporadically,even in patients in relatively good condition who have a low risk of chemotherapyinduced toxicity,often causing the failure of irinotecanbased chemotherapy. Clinical pharmacological studies have revealed that such severe toxicity is related to exposure to SN-38 and genetic polymorphisms in UDPglucuronosyltransferase 1A1 gene. The large interand intra-patient variability in systemic exposure to SN-38 is determined not only by genetic factors but also by physiological and environmental factors. This review first summarizes the roles of irinotecan in chemotherapy for metastatic CRC and then discusses the optimal dosing of irinotecan based on the aforementioned factors affecting systemic exposure to SN-38,with the ultimate goal of achieving personalized irinotecan-based chemotherapy.

UGT1A1 predicts outcome in colorectal cancer treated with irinotecan and fluorouracil

AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based regimens,FOLFIRI and IFL,were selected as second-line therapy for 138 Chinese mCRC patients.Genomic DNA was extracted from peripheral blood samples before treatment.UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism,respectively.Gene polymorphisms of UGT1A1*28,UGT1A1*6 and promoter enhancer region of TS were analyzed.The relationship between genetic polymorphisms and clinical outcome,that is,response,toxicity and survival were assessed.Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes.Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography.Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared.RESULTS:One hundred and eight patients received the FOLFIRI regimen,29 the IFL regimen,and one irinotecan monotherapy.One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation.One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS.Patients showed a higher frequency of wild-type UGT1A1*28(TA6/6) compared with a Caucasian population(69.9% vs 45.2%).No significant difference was found between response rates and UGT1A1 genotype,although wild-type showed lower response rates compared with other variants(17.9% vs 24.2% for UGT1A1*28,15.7% vs 26.8% for UGT1A1*6).When TS was considered,the subgroup with homozygous UGT1A1*28(TA7/7) and non-3RG genotypes showed the highest response rate(33.3%),while wild-type UGT1A1*28(TA6/6) with non-3RG only had a 13.6% response rate,but no significant difference was found.Logistic regression showed treatment duration was closely linked to clinical response.In toxicity comparison,UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea(27.8% vs 100%),and significantly reduced the risk of grade 4 neutropenia compared with TA7/7(7.8% vs 37.5%).Wild-type UGT1A1*6(G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant(A/A) genotype(13.0% vs 40.0%).Taking UGT1A1 and TS genotypes together,lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes,when TA6/6 was compared with TA7/7(35.3% vs 100.0%).No significant association with time to progression(TTP) and overall survival(OS) was observed with either UGT1A1 or TS gene polymorphisms,although slightly longer TTP and OS were found with UGT1A1*28(TA6/6).Irinotecan PK was investigated in 34 patients,which showed high area under concentration curve(AUC) of irinotecan and SN-38,but low AUC ratio(SN-38G /SN-38) in those patients with UGT1A1*28 TA7/7.CONCLUSION:A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients.

UGT1A1 gene polymorphism: Impact on toxicity and efficacy of irinotecan-based regimens in metastatic colorectal cancer

AIM: To investigate the correlation between uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) gene polymorphisms and irinotecan-associated side effects and parameters of drug efficacy in patients with metastatic colorectal cancer (mCRC) receiving a low-dose weekly irinotecan chemotherapeutic regimen. METHODS: Genotypes were retrospectively evaluated by gene scan analysis on the ABI 310 sequencer of the TATAA box in the promoter region of the UGT1A1 gene in blood samples from 105 patients who had received 1st line irinotecan-based chemotherapy for mCRC. RESULTS: The distribution of the genotypes was as follows: wild type genotype (WT) (6/6 ) 39.0%, heterozygous genotype (6/7) 49.5%, and homozygous genotype (7/7) 9.5%. The overall response rate (OR) was similar between patients carrying the (6/7, 7/7) or the WT genotype (6/6) (44.3% vs 43.2%, P = 0.75). Neither time to progression [(TTP) 8.1 vs 8.2 mo, P = 0.97] nor overall survival [(OS) 21.2 vs 18.9 mo, P = 0.73] differed significantly in patients who carried the(6/6) when compared to the (6/7, 7/7) genotype. No significant differences in toxicity were observed: Grade 3 and 4 delayed diarrhoea [(6/7, 7/7) vs (6/6); 13.0% vs 6.2%, P =0.08], treatment delays [(6/7, 7/7) vs (6/6); 25.1% vs 19.3%, P = 0.24] or dose reductions [(6/7, 7/7) vs (6/6); 21.5% vs 27.2%, P = 0.07].CONCLUSION: This analysis demonstrates the non-significant influence of the UGT1A1 gene polymorphism on efficacy and rate of irinotecan-associated toxicity in mCRC patients receiving low-dose irinotecan based chemotherapy.

Severe irinotecan-induced toxicity in a patient with UGT1A1*28 and UGT1A1*6 polymorphisms

Many studies have demonstrated the impact of UGT1A1 on toxicity of irinotecan. In particular, patients bear-ing UGT1A1*28 (TA 7/7) have a higher risk of severe neutropenia and diarrhea. Based on this, prescribers of irinotecan are advised that patients with UGT1A1*28 (TA 7/7) should start with a reduced dose of irinotecan, although a particular dose is not specified. Research in Asian countries has shown a lower incidence of UG-T1A1*28 (TA 7/7), while UGT1A1*6 (A/A) is more often found and is associated with severe irinotecan-related neutropenia. We report here a case of a metastatic colorectal cancer patient who is heterozygous for the UGT1A1*28 polymorphism (TA 6/7) as well as the UG-T1A1*6 polymorphism (G/A). The patient was treated with FOLFIRI for 9 cycles and underwent two irinote-can dose reductions according to pharmacokinetic data regarding exposure to the active metabolite, SN-38. Simultaneous heterozygous UGT1A1*28 and UGT1A1*6 polymorphisms may produce higher exposure to SN-38 and a higher risk of adverse effects related to irinote-can. Additional studies will be necessary to determine the optimal starting dose of irinotecan for patients with both UGT1A1*28 and UGT1A1*6 polymorphisms.

Predictive effects of bilirubin on response of colorectal cancer to irinotecan-based chemotherapy

AIM: To examine the predictive effects of baseline serum bilirubin levels and UDP-glucuronosyltransferase(UGT) 1A1*28 polymorphism on response of colorectal cancer to irinotecan-based chemotherapy.METHODS: The present study was based on a prospective multicenter longitudinal trial of Chinese metastatic colorectal cancer(m CRC) patients treated with irinotecan-based chemotherapy(NCT01282658). Baseline serum bilirubin levels, including total bilirubin(TBil) and unconjugated bilirubin(UBil), were measured,and genotyping of UGT1A1*28 polymorphism was performed. Receiver operating characteristic curve(ROC) analysis was used to determine cutoff values of TBil and UBil. The TBil values were categorized into > 13.0 or ≤ 13.0 groups; the UBil values were categorized into > 4.1 or ≤ 4.1 groups. Combining the cutoff values of TBil and UBil, which was recorded as Co Bil, patients were classified into three groups. The classifier's performance of UGT1A1*28 and Co Bil for predicting treatment response was evaluated by ROC analysis. Associations between response and Co Bil or UGT1A1*28 polymorphism were estimated using simple and multiple logistic regression models. RESULTS: Among the 120 m CRC patients, the serum bilirubin level was significantly different between the UGT1A1*28 wild-type and mutant genotypes. Patients with the mutant genotype had an increased likelihood of a higher TBil(P = 0.018) and a higher UBil(P = 0.014) level compared with the wild-type genotype. Patients were stratified into three groups based on Co Bil. Group 1 was patients with TBil > 13.0 and UBil > 4.1; Group 2 was patients with TBil ≤ 13.0 and UBil > 4.1; and Group 3 was patients with TBil ≤ 13.0 and UBil ≤ 4.1. Patients in Group 3 had more than a 10-fold higher likelihood of having a response in the simple(OR = 11.250; 95%CI: 2.286-55.367; P = 0.003) and multiple(OR = 16.001; 95%CI: 2.802-91.371; P = 0.002) analyses compared with the Group 1 individuals. Patients carrying the UGT1A1*28(TA)7 allele were 4-fold less likely to present with a response compared with the individuals harboring a homozygous(TA)6 genotype in the simple(OR = 0.267; 95%CI: 0.100-0.709; P = 0.008) and multiple(OR = 0.244; 95%CI: 0.088-0.678; P = 0.007) analyses. Classifier's performance of Co Bil and UGT1A1*28 were comparable.CONCLUSION: Co Bil and UGT1A1*28 are both independent biomarkers for predicting the treatment response of m CRC patients to irinotecan-based chemotherapy. After validation, Co Bil, an easily determinable index in the clinic, might be helpful in facilitating stratification of m CRC patients for individualized treatment options.

Capecitabine and irinotecan with and without bevacizumab for advanced colorectal cancer patients

AIM:To investigate the efficacy and safety of capecitabine plus irinotecan±bevacizumab in advanced or metastatic colorectal cancer patients. METHODS:Forty six patients with previously untreated,locally-advanced or metastatic colorectal cancer(mCRC) were recruited between 2001-2006 in a prospective open-label phaseⅡtrial,in German community-based outpatient clinics.Patients received a standard capecitabine plus irinotecan(CAPIRI) or CAPIRI plus bevacizumab(CAPIRI-BEV) regimen every 3 wk. Dose reductions were mandatory from the first cycle in cases of>grade 2 toxicity.The treatment choice of bevacizumab was at the discretion of the physician.Theprimary endpoints were response and toxicity and secondary endpoints included progression-free survival and overall survival. RESULTS:In the CAPIRI group vs the CAPRI-Bev group there were more female than male patients(47% vs 24%) ,and more patients had colon as the primary tumor site(58.8%vs 48.2%) with fewer patients having sigmoid colon as primary tumor site(5.9%vs 20.7%) .Grade 3/4 toxicity was higher with CAPIRI than CAPIRI-Bev:82%vs 58.6%.Partial response rates were 29.4%and 34.5%,and tumor control rates were 70.6%and 75.9%,respectively.No complete responses were observed.The median progression-free survival was 11.4 mo and 12.8 mo for CAPIRI and CAPIRI-Bev,respectively.The median overall survival for CAPIRI was 15 mo(458 d) and for CAPIRI-Bev 24 mo(733 d) .These differences were not statistically different.In the CAPIRI-Bev,group,two patients underwent a full secondary tumor resection after treatment,whereas in the CAPIRI group no cases underwent this procedure. CONCLUSION:Both regimens were well tolerated and offered effective tumor growth control in this outpatient setting.Severe gastrointestinal toxicities and thromboembolic events were rare and if observed were never fatal.

Irinotecan therapy and molecular targets in colorectal cancer: A systemic review

Irinotecan is the second line chemotherapy for advanced stage colorectal cancer (CRC) after failure of first line chemotherapy with oxaliplatin and 5-fluorouracil. The aim of this review is to analyse the data on irinotecan as second line chemotherapy for advanced CRC and the potential roles of the molecular markers, p53 and vascular endothelial growth factor (VEGF) in the management of advanced CRC. Thus, the English literature from 1980 to 2008 concerning irinotecan, p53, VEGF and CRC was reviewed. On review, Phase and clinical trials showed thatirinotecan improves pain-free survival, quality of life, 1-year survival, progression-free survival and overall survival in advanced CRC. p53 and VEGF were expressed in CRC and had a predictive power of aggressive clinical behaviour in CRC. Irinotecan sensitizes p53 wild type, mutant and null cells to Fasmediated cell apoptosis in CRC cells. Wild type p53 cells were more sensitive to irinotecan than mutated p53. Irinotecan has an anti-VEGF effect inhibiting endothelial cell proliferation, increasing apoptosis and reducing microvascular density which is onlylimited by irinotecan toxicity levels. To conclude, irinotecan improves the patient's quality of life and the survival rates of patients with advanced CRC. p53 and VEGF status of the patients' tumour is likely to affect the responsiveness of CRC to irinotecan. It is recommended that studies of the expression of these molecular markers in relation to chemoresponsiveness ofirinotecan should be carried out for better management of patients with advanced CRC.

Highly sensitive fluorescence quantification of irinotecan in biological fluids with the aid of second-order advantage

A rapid,green and highly sensitive excitation-emission matrix（EEM） fluorescence method was proposed for analysis of irinotecan（CPT-11） in biological fluids including human plasma and urine samples of uncalibrated interferences with the aid of second-order advantage.Due to the serious spectral overlapping from biological matrices,the parallel factor analysis（PARAFAC） and the alternating normalization-weighted error（ANWE） have been recommended to perform directly calibration and overcome the problem which makes the traditional fluorospectrophotometer in trouble.Satisfactory results can be achieved.Furthermore, performance of the proposed method was evaluated based on figures of merit and some statistical parameters.The accuracy of both algorithms was validated by the elliptical joint confidence region（EJCR） test.The precision and repeatability were also investigated by the relative standard deviations（RSDs） of intra-day and inter-day.

Polyethylene glycol microspheres loaded with irinotecan for arterially directed embolic therapy of metastatic liver cancer

AIM To study tumor response, and tolerability of arterially directed embolic therapy(ADET) with polyethylene glycol embolics loaded with irinotecan for the treatment of colorectal cancer liver metastases(CRC-LM). Secondary objectives were to monitor quality of life, time to progression and survival of patients.METHODS Patients were included in the study if they were affected by CRC-LM, refractory to systemic chemotherapy, treated with ADET using polyethylene glycol embolics, and had liver involvement < 50%. Tumor response, performance status(PS), tumor marker antigens, and quality of life(QoL) were monitored at 1, 3 and 6 mo after ADET. QoL was assessed with the Palliative Performance Scale(PPS).RESULTS We treated 50 consecutive CRC-LM patients with ADET using polyethylene glycol embolics. Their tumor response one month after ADET was: 28% of complete response(CR), 48% of partial response(PR), 8% stable disease(SD), and 16% of progression. Tumor response 3 mo after ADET was CR 24%, PR 38%, SD 19% and progression disease(PD) 19%. Tumor response 6 mo after ADET was CR 18%, PR 44%, SD 21% and PD 18%. QoL was 90% PPS at each time point. Median time to progression for patients who progressed was 2.5 mo(range 0.8-6). Median follow-up was 14 mo(0.8-25 range). ADETs were performed with no complications. Observed side effects(mild or moderate intensity) were: Pain in 32% of patients, increase of transaminase levels in 20% and fever in 14%, whereas 30% of patients did not complain any adverse event. CONCLUSION The treatment of unresectable CRC-LM with ADET using polyethylene glycol microspheres loaded with irinotecan was effective in tumor response and resulted in mild toxicity, and good QoL.

Bevacizumab plus infusional 5-fluorouracil,leucovorin and irinotecan for advanced colorectal cancer that progressed after oxaliplatin and irinotecan chemotherapy:A pilot study

AIM： To evaluate the combination of bevacizumab with infusional 5-fluorouracil （5-FU）, leucovorin （LV） and irinotecan （FOLFIRI） in patients with advanced colorectal cancer （CRC） pretreated with combination regimens including irinotecan and oxaliplatin. METHODS： Fourteen patients （median age 56 years） with advanced CRC, all having progressed after oxaliplatin- and irinotecan-based combination chemotherapy, were enrolled in this study. Patients were treated with 2 h infusion of irinotecan 150 mg/m2 on d 1, plus bevacizumab 5 mg/kg iv infusion for 90 min on d 2, and iv injection of LV 20 mg/m2 followed by a bolus of 5-FU 400 mg/m2 and then 22 h continuous infusion of 600 mg/m2 given on two consecutive days every 14 d. RESULTS： The median number of cycles of chemotherapy was six （range 3-12）. The response rate was 28.5%, one patient had a complete response, and three patients had a partial response. Eight patients had stable disease. The median time to progression was 3.9 mo （95% CI 2.0-8.7）, and the median overall survival was 10.9 mo （95% CI 9.6-12.1）. Grade 3/4 neutropenia occurred in five patients, and two of these developed neutropenic fever. Grade 3 hematuria and hematochezia occurred in one. Grade 2 proteinuria occurred in two patients. However, hypertension, bowel perforation or thromboembolic events did not occur in a total of 90 cycles. CONCLUSION： Bevacizumab with FOLFIRI is well tolerated and a feasible treatment in patients with heavily treated advanced CRC.

Phase Ⅱ study of protracted irinotecan infusion and a low-dose cisplatin for metastatic gastric cancer

AIM: To test protracted irinotecan infusion plus a low-dose cisplatin in this Phase Ⅱ trial to decrease its toxic-ity. METHODS: The eligibility criteria were: (1) histologi-cally proven measurable gastric cancer; (2) performance status of 0 or 1; (3) no prior chemotherapy or comple-tion of prior therapy at least 4 wk before enrollment; (4) adequate function of major organs; (5) no other active malignancy; and (6) written informed consent. The regi-men consisted of irinotecan (60 mg/m2) on d 1 and 15 by 24-h infusion and cisplatin (10 mg/m2) on d 1, 2, 3, 15, 16, and 17. Treatment was repeated every 4 wk. RESULTS: Thirty-one patients were registered between April 2000 and January 2001. The response rate for all 31 patients, 20 patients without prior chemotherapy, and 11 patients with prior chemotherapy was 52% (16/31), 60% (12/20), and 36% (4/11), respectively. The median survival time was 378 d. The median number of courses given to all patients was 2. Grade 4 neutropenia oc-curred in 11 (35%) patients, while grade 3 to 4 diarrhea or nausea occurred in 1 (3%) and 3 (10%) patients, respectively. Fatigue was minimal as grade 1 fatigue was found only in 3 (10%) patients. Other adverse events were mild and no treatment-related deaths occurred.CONCLUSION: This regimen showed a high level of ac-tivity and acceptable toxicity in patients with metastatic gastric cancer.

Development of a method to quantify total and free irinotecan and 7-ethyl-10-hydroxycamptothecin(SN-38) for pharmacokinetic and bio-distribution studies after administration of irinotecan liposomal formulation

In 2015,liposomal formulation of irinotecan(ONIVYDE)has been approved by FDA and widely applied in the treatment of pancreatic cancer.ONIVYDE is a novel liposome formulation,entrapping CPT-11 in the aqueous core of vesicles using a modified gradient loading method.Due to toxicity concerns,it is essential to explore a rapid and reliable method to effectively isolate and quantify the non-liposomal,namely,free CPT-11and total CPT-11 in plasma.This study focuses on separation of non-liposomal CPT-11,evaluation of the pharmacokinetics of free CPT-11 and total CPT-11 and bio-distribution after intravenous administration of CPT-11 liposome.Free CPT-11 in plasma was separated by solid-phase extraction(SPE).The amount of total CPT-11 and main metabolite 7-ethyl-10-hydroxycamptothecin(SN-38)in plasma was quantified by ultra-performance liquid chromatography–MS/MS.The calibration curves fitted well and lower limit of quantitation for SN-38,free CPT-11,total CPT-11 and CPT-11 in tissue and were 5 ng/ml,10 ng/ml,4.44 ng/ml and 25 ng/ml respectively.The recoveries,precision and accuracy of the method appear satisfactory.Using this method,the pharmacokinetics and bio-distribution of CPT-11 liposome formulation after an intravenous dose of 2.5 mg/kg were then investigated.

Non-platinum-based chemotherapy for treatment of advanced gastric cancer:5-fluorouracil,taxanes,and irinotecan

Despite numerous advances in treatment options,advanced gastric cancer(AGC)remains a major public health issue and the leading cause of cancer-related deaths.Cisplatin is one of the most effective broadspectrum anticancer drugs for AGC and a doublet combination regimen of either cisplatin-based or 5-fluorouracil(5FU)-based chemotherapy is generally used for treatment of patients with AGC.However,there is still no consensus on the best regimen for treating AGC.Recently,various new chemotherapeutic agents,including oral 5FU,taxanes,and irinotecan,have been identified as improving the outcomes for AGC when used as a single agent or in combination with nonplatinum chemotherapy.Nonetheless,it is still unclear whether non-platinum-based chemotherapy is a viable treatment option for patients with AGC.Accordingly,this review focuses on the efficacy and tolerability of non-platinum-based chemotherapy for patients with AGC.

Efficacy of irinotecan-based chemotherapy after exposure to an anti-PD-1 antibody in patients with advanced esophageal squamous cell carcinoma

Objective:Several anti-programmed cell death 1(anti-PD-1)antibodies have demonstrated potential efficacy in the treatment of advanced esophageal squamous cell cancer(ESCC).However,the response to subsequent chemotherapy after the failure of PD-1 blockade in ESCC patients has not been reported,and the optimal sequencing of immunotherapy and chemotherapy remains controversial.The aim of the present study was to evaluate responses to irinotecan-based subsequent chemotherapy in advanced ESCC patients who had progressed after treatment with camrelizumab(SHR-1210),a novel anti-PD-1 antibody.Methods:We retrospectively reviewed the medical records of patients with advanced ESCC treated with camrelizumab at a single institution.Consecutive patients who received subsequent irinotecan-based chemotherapy were selected for data collection and analysis.Results:Overall,a total of 28 patients were included.All patients had received at least two lines of systemic treatment prior to irinotecan salvage.The most common regimen that was administered after PD-1 blockade was irinotecan in combination with 5-fluorouracil(5-Fu)(or its derivatives),which was given to 19 patients.The objective response rate(ORR)and disease control rate(DCR)were 17.9%(5/28)and 64.3%(18/28),respectively,with 5(17.9%)patients achieving a partial response and 13(46.4%)having stable disease.The median progressionfree survival(PFS)was 3.18[95%confidence interval(95%CI),2.48-3.88]months and the median overall survival(OS)was 6.23(95%CI,4.71-7.75)months.No new safety issues,either immune-related or otherwise,were observed.Conclusions:Our results suggested that the response to irinotecan-based chemotherapy after PD-1 blockade in advanced ESCC patients appeared similar to that previously observed in patients who had not received PD-1 antibodies,and further study in larger cohorts or randomized trials is warranted to verify our observation.

Active loading liposomal irinotecan hydrochloride:Preparation,in vitro and in vivo evaluation

The aim of the present study was to investigate the effect of various transmembrane ammonium salt gradients and different lipid composition on the loading efficiency of liposomal formulations of irinotecan hydrochloride(CPT-11),their behavior in vivo and cytotoxicity.Among ammonium salts studied,ammonium sulfate was successfully used to load CPT-11 into liposomes with the highest encapsulation efficiency.Subsequently,liposomal CPT-11 with different lipid composition was prepared by ammonium sulfate gradient method.CPT-11 can be loaded to a level over 90%into liposomes composed of soybean phospholipids/cholesterol(SPC-L)or hydrogenated natural soybean phospholipids/cholesterol(HSPC-L).In vitro release profiles were also investigated,indicating that HSPC-L had a lower release than that in SPC-L.In vivo,encapsulation of CPT-11 in both liposomal formulations showed higher area under the curve(AUC),a lower rate of clearance(CL)and smaller volume of distribution for CPT-11 than those of irinotecan hydrochloride solution(CPT-11-S).However,CL and AUC of 7-ethyl-10-hydroxycamptothecin(SN-38)were moderately improved in HSPC-L group.Based on the results of comparative pharmacokinetics of liposomal CPT-11 with different lipid composition,the in vitro cytotoxicity of HSPC-L was evaluated with human tumor cell.The result indicated that liposomal CPT-11 showed a great enhancement in vitro cytotoxicity.The results suggested that entrapment of CPT-11 in liposomes especially in those with high phase-transition temperature lipid by ammonium sulfate gradient would be a promising formulation with a better in vivo behavior.

Sirolimus,bevacizumab,5-Fluorouracil and irinotecan for advanced colorectal cancer:A pilot study

AIM： To evaluate the efficacy and the safety of combined 5-Fluorouracil, irinotecan, bevacizumab and sirolimus in refractory advanced colorectal carcinoma. METHODS： We initiated a regimen with at day 1 an injection （iv） of bevacizumab at 5 mg/kg, followed by 180 mg/m^2 irinotecan, followed by Leucovorin 400 mg/m^2, followed by a 5-Fluorouracil bolus 400 mg/m^2 and a 46-h infusion 2400 mg/m^2. Sirolimus was given orally as continuous administration of 2 mg twice a day every days. This treatment was repeated every 14 d. RESULTS： A total of 12 patients were enrolled. All patients presented with metastatic disease that had failed at least three lines of chemotherapy that contained oxaliplatin, irinotecan and bevacizumab. Cetuximab failure was also observed in all K-Ras wildtype patients. The median number of cycles was 8.5 （range 2-20） and clinical benefit was observed in eight patients. The median time to progression was 5 mo and the median survival was 8 too. Grade 3 neutropenia developed in four patients, and grade 3 diarrhea and stomatitis in two.CONCLUSION： The combination regimen of 5-Fluorouracil,irinotecan, bevacizumab and sirolimus in advanced colorectal carcinoma after failure of dassical be.absent is feasible and promising. Further evaluation of this combination is required.

槲皮素结合Irinotecan或SN-38治疗或许对胃癌细胞的生长有抑制作用

目前尚无槲皮素结合irinotecan／SN-38治疗胃癌（GC）的研究报道。本文研究的目的是探讨槲皮素结合iri—notecan／SN-38能否更有效地降低癌细胞转移相关基因和蛋白质的表达，并减缓GC的发展。对象与方法：①体外研究。将经培养后的人类胃癌细胞（AGS）分别放入槲皮素（6．25，12．5，25，50，100μM）、SN-38（2．5，5，25，50，100nM）和槲皮素＋SN-38中进行48h等处理后.

Short-term efficacy and influencing factors of conventional chemotherapy combined with irinotecan in patients with advanced gastric cancer

BACKGROUND Gastric cancer is one of the most common cancers worldwide, with a 5-year survival rate of only 20%. The age of onset of gastric cancer is in line with the general rule of cancer. Most of them occur after middle age, mostly between 40and 60 years old, with an average age of about 50 years old, and only 5% of patients are under 30 years old. The incidence of male is higher than that of female.AIM To investigate the short-term efficacy and influencing factors of chemotherapy combined with irinotecan in patients with advanced gastric cancer.METHODS Eighty patients with advanced gastric cancer who were treated in our hospital from January 2019 to January 2022 were selected. The patients were divided into an observation group(n = 40) and control group(n = 40) by the envelope method.The control group was given preoperative routine chemotherapy. The observation group was treated with irinotecan in addition to the chemotherapy given to the control group. The short-term efficacy of treatment in the two groups, as well as tumor marker levels and quality of life before and after treatment were evaluated.RESULTS The short-term treatment effect in the observation group was better than that in the control group(P < 0.05), and the total effective rate was 57.50%. The age and proportion of tumor node metastasis(TNM) stage IV patients with ineffective chemotherapy in the observation group were(65.12 ± 5.71) years and 52.94%,respectively, which were notably higher than those of patients with effective chemotherapy(P < 0.05), while the Karnofsky Performance Scale score was(67.70± 3.83) points, which was apparently lower than that of patients with effective chemotherapy(P <0.05). After 3 mo of treatment, the SF-36 scale scores of physiological function, energy, emotional function, and mental health in the observation group were 65.12 ± 8.14, 54.76 ± 6.70, 47.58 ± 7.22,and 66.16 ± 8.11 points, respectively, which were considerably higher than those in the control group(P < 0.05). The incidence rates of grade Ⅲ-Ⅳ diarrhea and grade Ⅲ-Ⅳ thrombocytopenia in the observation group were 32.50% and 25.00%, respectively, which were markedly higher than those in the control group(P < 0.05).CONCLUSION Chemotherapy combined with irinotecan in patients with advanced gastric cancer has a good short-term efficacy and can significantly reduce serum tumor markers and improve the quality of life of patients. The efficacy may be affected by the age and TNM stage of the patients, and its long-term efficacy needs further study.

Pharmacogenetics of irinotecan:An ethnicity-based prediction of irinotecan adverse events

Irinotecan is now regarded as the most active drug for the treatment of colorectal cancer.However,one of the most difficult issues oncologists face is deciding the optimal dose for an individual patient,as each individual shows different outcomes even at the same dose with regard to treatment related adverse events,ranging from no toxicity to a lethal event.Inherited genetic polymorphism of a single gene or multiple genes(haplotype or linkage disequilibrium) involved in SN-38 glucuronidation,a predominant route of irinotecan detoxification,is now recognized as a significant factor that can alter the incidence of side effects.Attempts to explore such inherited genetic variability have been focused on elucidating interindividual as well as interethnic differences.Genotyping studies in relation to adverse events in an individual or in a group of similar ethnicity should contribute to establishing individualoriented or ethnicity-oriented irinotecan treatment regimens.This review highlights current single-or multi-tired approaches for the elucidation of genetic predispositions of patients to severe toxicities,especially among Asians.The purpose of this is to contribute to minimizing toxicity by dose modifications,with the consequent aim of maximizing dose intensity and efficacy,an ultimate goal of irinotecan-individualized therapy.

Cetuximab plus irinotecan in pretreated metastatic colorectal cancer patients:The ELSIE study

AIM:To evaluate the efficacy and safety of cetuxim-ab plus irinotecan in irinotecan-refractory metastatic colorectal cancer (mCRC) patients from South-East Asia and Australia. METHODS:In this open-label,phase Ⅱ study,the main eligibility criteria were epidermal growth factor receptor-positive mCRC with progressive disease within 3 mo of an irinotecan-based regimen as the most recent chemotherapy. Patients received cetuximab 400 mg/m2 initially,then 250 mg/m2 every week,with the same regimen of irinotecan on which the patients had progressed (4 pre-defined regim-ens allowed). The prim-ary objective was evaluation of progression-free survival (PFS) at 12 wk. Secondary objectives included a further investigation of PFS,and an assessment of the overall response rate (ORR),duration of response,time to treatment failure (TTF),overall survival and the safety profile. RESULTS:One hundred and twenty nine patients were enrolled from-25 centers in the Asia-Pacific region and of these 123 received cetuximab plus irinotecan. The most common recent irinotecan regimen used was 180 mg/m2 every 2 wk which had been used in 93 patients (75.6%). The PFS rate at 12 wk was 50% (95% confidence interval (CI,41-59) and m-edian PFS tim-e was 12.1 wk (95% CI:9.7-17.7). The ORR was 13.8% (95% CI:8.3-21.2) and disease control rate was 49.6% (95% CI:40.5-58.8). Median duration of response was 31.1 wk (95% CI:18.0-42.6) and median overall survival was 9.5 mo (95% CI,7.5-11.7). The median TTF was 11.7 wk (95% CI:9.1-17.4). Treatment was generally well tolerated. The most common grade 3/4 adverse events were diarrhea (13.8%),neutropenia (8.9%),rash (5.7%) and vomiting (5.7%).CONCLUSION:In patients from Asia and Australia,this study confirm-s the activity and safety of cetuxim-ab plus irinotecan observed in previous studies in Europe and South America.