DNA minor groove; covalent binder

PM01183 is a newly developed synthetic alkaloid tetrahydroisoquinoline that is used to treat solid tumors. PM01183: Double-strand breaks in living cells are caused by DNA adducts, which lead to the accumulation of S-phase and subsequent cell disinfection. With an average GI50 value of 2.7 nM, PM01183's strong cytotoxic activity was found in a panel of 23 cell lines [2]. In vitro, lurbinectedin significantly inhibits human ovarian clear cell carcinoma (CCC) cells that are both chemically sensitive and robust[1].

---

Lurbinectedin exhibited significant antitumor activity toward chemosensitive and chemoresistant CCC cells in vitro. Among the tested combinations, Lurbinectedin (PM01183) plus SN-38 resulted in a significant synergistic effect. This combination also had strong synergistic effects on both the cisplatin-resistant and paclitaxel-resistant CCC cell lines. Everolimus significantly enhanced the antitumor activity of lurbinectedin-based chemotherapies. [1]

---

Electrophoretic mobility shift assays demonstrated that Lurbinectedin (PM01183) bound to DNA. Fluorescence-based thermal denaturation experiments showed that the most favourable DNA triplets providing a central guanine for covalent adduct formation are AGC, CGG, AGG and TGG. These binding preferences could be rationalized using molecular modelling. PM01183-DNA adducts in living cells give rise to double-strand breaks, triggering S-phase accumulation and apoptosis. The potent cytotoxic activity of PM01183 was ascertained in a 23-cell line panel with a mean GI(50) value of 2.7 nM[2].

Lurbinectedin effectively suppressed tumor growth in CCC cell xenografts. There is a notable synergistic effect between SN-38 and luerbinectedin [1]. PM01183 markedly suppressed tumor growth in a four-cell xenograft model of human cancer, while lurbinectedin or NSC 119875 combination therapy effectively cured NSC 119875-sensitive and NSC 119875-combined single preclinical ovarian carcinoma tumors in animals. The combined treatment showed the greatest positive results, particularly for NSC 119875. inside tumors. Reduced proliferation, increased aberrant mitotic rates in malignancies, and triggered apoptosis are linked to luerbinectedin growth inhibition [3].

---

In vivo growth-inhibitory effects of Lurbinectedin (PM01183) on ovarian CCC [1]
To examine the in vivo growth-inhibitory effects of Lurbinectedin (PM01183) , researchers employed an s.c. xenograft model in which athymic mice were s.c. inoculated with RMG1 cells. Overall, the drug treatment was well tolerated throughout the study and did not cause any apparent toxicities. The changes in the body weights of the mice are shown in Fig 2A. As shown in Fig 2B, the mean RMG1-derived tumor burden in the mice treated with lurbinectedin was 171.9 mm3, whereas it was 537.3 mm3 in the PBS-treated mice. Overall, treatment with lurbinectedin decreased the RMG1-derived tumor burden by 68.0% compared with PBS treatment.

---

Researchers performed xenograft studies to test whether the cytotoxicity of Lurbinectedin (PM01183) translates into in vivo anti-tumour activity. NCI-H460 (lung), A2780 (ovary), HT29 (colon) and HGC-27 (gastric) cells were xenografted into the right flank of athymic nu/nu mice. Once the tumours reached c. 150 mm3, the mice were randomized into groups of 10–15 mice each and either vehicle or PM01183 (0.18 mg·kg−1·day−1) was intravenously administered in three consecutive weekly doses. At the drug doses used in the experiment, no significant toxicity or body weight loss was observed in the treated animals (data not shown). As shown in Figure 4, PM01183 presented anti-tumour activity with a statistically significant inhibition of tumour growth in the four tested models [2].

---

Researchers showed that single Lurbinectedin (PM01183) or cisplatin-combined therapies were effective in treating cisplatin-sensitive and cisplatin-resistant preclinical ovarian tumor models. Furthermore, the strongest in vivo synergistic effect was observed for combined treatments, especially in cisplatin-resistant tumors. Lurbinectedin tumor growth inhibition was associated with reduced proliferation, increased rate of aberrant mitosis, and subsequent induced apoptosis. Conclusions: Taken together, preclinical orthotopic ovarian tumor grafts are useful tools for drug development, providing hard evidence that lurbinectedin might be a useful therapy in the treatment of EOC by overcoming cisplatin resistance[3].

DNA electrophoretic mobility shift assay [2]
The binding assay was performed with a 250 bp PCR product from the human adiponectin gene. After incubation with appropriate concentrations of the compound at 25°C during 1 h, the DNA was subjected to electrophoresis in a 2% (w/v) agarose/TAE gel, stained with 1 µg·mL−1 ethidium bromide and photographed.

---

DNA melting assay [2]
Synthetic oligodeoxynucleotides with one strand 5′-end-labelled with the fluorophore 6-carboxyfluorescein and the complementary strand 3′-end-labelled with the quencher tetramethylrhodamine were synthesized at a CRO cpmpany (Table S1). For the experiments, we followed the methodology previously described (Negri et al., 2007; Casado et al., 2008) using a 7500 Fast Real-Time PCR System. Analyses of the raw data obtained for each oligodeoxynucleotide using an in-house developed Visual Basic Application running on Microsoft Excel yielded estimates of both the increase in melting temperature (ΔTm) brought about by drug binding, relative to the free DNA molecule, and the ligand concentration that produces half the maximal change in melting temperature (C50). The inverse of this latter value (1/C50) was taken as a measure of the relative DNA binding affinity, and the parameter ΔTm(max) was used to reflect the relative stability of the DNA–ligand complexes (Negri et al., 2007).

Cell proliferation assay [1]
The MTS assay was used to analyze the effects of each drug. Cells were plated in 96-well plates and exposed to the drugs at different concentrations. After 48 hours’ incubation, the number of surviving cells was assessed by determining the A490nm of the dissolved formazan product after the addition of MTS for 1 hour, as described by the manufacturer. Cell viability was calculated as follows: Aexp group / Acontrol × 100. The experiments were repeated at least three times, and representative results are shown.

---

Cell cycle analysis [1]
CCC cells (2×105) were incubated with Lurbinectedin (PM01183) at the indicated concentrations for 48 hours. The cells were then fixed with 75% ethanol overnight at -20°C and stained with propidium iodide (PI; 50 μg/mL) in the presence of RNase A (100 μg/mL; Roth) for 60 minutes at 4°C. In each experiment, the cell cycle distribution was determined by analyzing 10,000 cells using a FACScan flow cytometer and Cell Quest software (Becton Dickinson, NJ, USA), as reported previously. The experiments were repeated at least three times, and representative results are shown.

---

Detection of apoptosis [1]
CCC cells (2~5×105) were treated with Lurbinectedin (PM01183) , SN38 or in combination of the two drugs at the indicated concentrations for 48 hours. Then, the cells were harvested and stained with PI and annexin V using the annexin V-fluorescein isothiocyanate (FITC) apoptosis detection kit, according to the manufacturer’s instructions. Fluorescence data were collected using flow cytometry, as reported previously. The sum total of early apoptotic cells (annexin V(+), PI(−) cells) and late apoptotic cells (annexin V(+), PI(+) cells) was defined as the total number of apoptotic cells. The experiments were repeated at least three times, and representative results are shown.

---

Isobologram method and the combination index [1]
The isobologram method relies on determining the combined concentrations of D1 (lurbinectedin) and D2 (the drug used in combination with Lurbinectedin (PM01183) ) that result in a fractional kill value of 50%. For each experimental concentration of lurbinectedin, the concentration of D2 that would cause the desired effect when used in combination with lurbinectedin was found by non-linear fitting of the concentration-effect relationship of D2 to the given lurbinectedin concentration. Conversely, for each experimental concentration of D2, the lurbinectedin concentration that would cause the desired effect when used in combination with D2 was found by non-linear fitting of the concentration-effect relationship of lurbinectedin to the particular D2 concentration. In this manner, multiple pairs of drug concentrations that achieved the desired isoeffect were found. For each pair of drug concentrations (DLurbinectedin, DD2) that produced a fractional kill value of 50%, the combination index (CI) was calculated as follows: CI = DLurbinectedin / IC50Lurbinectedin + DD2 / IC50D2. CI values of <1 indicate synergism, CI values of 1 indicate an additive effect, and CI values of >1 indicate antagonism. The significance of the differences between the mean CI values for each combination and 1 was evaluated using a 2-tailed t test. The experiments were repeated at least three times, and representative results are shown.

---

Western blot analysis [1]
CCC cells were treated with Lurbinectedin (PM01183) or other agents for appropriate periods of time, washed twice with ice cold phosphate-buffered saline (PBS), and lysed in radioimmunoprecipitation assay (RIPA) lysis buffer. The protein concentrations of the cell lysates were determined using the Bio-Rad protein assay reagent. Equal amounts of protein were applied to 5–20% polyacrylamide gels, and then the electrophoresed proteins were transblotted onto nitrocellulose membranes. After the membranes had been blocked, they were incubated with anti-PARP, anti-cleaved caspase 3, anti-P-gp, or anti-β-actin antibodies. The immunoblots were visualized with horseradish peroxidase-coupled goat anti-rabbit or anti-mouse immunoglobulins, using the enhanced chemiluminescence Western blotting system.

---

Cell culture and cytotoxicity [2]
All the tumour cell lines used in this study were obtained from the American Type Culture Collection. For the cytotoxicity experiments, cells were seeded in 96-well trays. Serial dilutions of Lurbinectedin (PM01183) dissolved in dimethyl sulphoxide (DMSO) were prepared and added to the cells in fresh medium, in triplicate. Exposure to the drug was maintained during 72 h and cellular viability was estimated from conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to its coloured reaction product, MTT formazan, which was dissolved in DMSO so as to measure absorbance at 540 nm with a POLARStar Omega Reader. Determination of the concentration giving 50% growth inhibition (GI50) values was performed by iterative non-linear curve fitting using the Prism 5.0 statistical software. The data presented are the average of three independent experiments performed in triplicate.

---

Fluorescent microscopy [2]
Cells were treated with the appropriate concentration of Lurbinectedin (PM01183) for 6 h, washed and then cultured for 18 additional hours. At the end of this period, they were fixed (4% paraformaldehyde), permeabilized (0.5% Triton X-100) and incubated with the primary anti-γ-H2AX monoclonal antibody for 1 h at 37°C. Thereafter the cells were washed and incubated with the AlexaFluor 594 secondary goat anti-mouse IgG for 30 min at 37°C. Finally, the slides were incubated with Hoechst 33 342 and mounted with Mowiol mounting medium. Pictures were taken with a Leica DM IRM fluorescence microscope equipped with a 100× oil immersion objective and a DFC 340 FX digital camera.

---

Cell cycle analysis [2]
For the cell cycle experiments and sub-G1 peak determination, cells were treated with the appropriate amount of Lurbinectedin (PM01183) for 12 h and 24 h, and then stained with 0.4 µg·mL−1 propidium iodide. Samples were analysed with a FACScalibur flow cytometer and the FlowJo7 cytometry analysis software.

Subcutaneous xenograft model [1]
\nPreliminary experiments were conducted to examine the effects of Lurbinectedin (PM01183) on ovarian CCC. Five- to 7-week-old nude mice (n = 12) had 1×107 RMG1 cells in 150 μL of PBS s.c. injected into their left flanks. When the tumors reached about 50 mm3 in size, the mice were assigned to one of two treatment groups. The first group (n = 6) was i.v. administered PBS, and the second group (n = 6) was i.v. administered lurbinectedin (0.180 mg/kg) each week for 6 weeks. The dose of lurbinectedin (0.180 mg/kg) used was based on that employed in a previous preclinical study of ovarian cancer, in which it showed significant in vivo antitumor activity. A second set of experiments was conducted to examine the antitumor effects of combination treatment involving lurbinectedin and irinotecan. We employed irinotecan in the in vivo experiments because the clinical use of SN-38 is limited by its poor aqueous solubility, and the goal of this study was to identify practical treatments that could be used in the clinical setting. Five- to 7-week-old nude mice (n = 18) had 1×107 RMG1 cells in 150 μL of PBS s.c. injected into their flanks. When the tumors reached about 50 mm3 in size, the mice were assigned to 1 of 3 treatment groups, which received PBS, CPT-11 (50 mg/kg weekly), or lurbinectedin (0.180 mg/kg weekly) plus CPT-11 (50 mg/kg weekly). Caliper measurements of the longest perpendicular diameter of each tumor were obtained twice a week and used to estimate tumor volume according to the following formula: V = L × W × D × π / 6, where V is the volume, L is the length, W is the width, and D is the depth.\n

---

\n\nAnti-tumour activity in xenograft murine models [2]
\nFour to 6-week-old athymic nu/nu mice were s.c. xenografted with NCI-H460 (lung), A2780 (ovary), HT29 (colon) and HGC-27 (gastric) cells into their right flank with c. 3 × 106 cells in 0.2 mL of a mixture (50:50; v:v) of Matrigel basement membrane matrix and serum-free medium. When tumours reached c. 150 mm3, mice were randomly assigned to treatment or control groups. Lurbinectedin (PM01183) was intravenously administered in three consecutive weekly doses (0.18 mg·kg−1·day−1) whereas the control animals received an equal volume of vehicle with the same schedule. Caliper measurements of the tumour diameters were made twice weekly and tumour volumes were calculated according to the following formula: (a·b)2/2, where a and b were the longest and shortest diameters respectively. Animals were humanely killed when their tumours reached 3000 mm3 or if significant toxicity (e.g. severe body weight reduction) was observed. Differences in tumour volumes between treated and control groups were evaluated using the Mann–Whitney U-test. Statistical analyses were performed by LabCat® v8.0 SP1.\n

---

\n\nDrug treatment of engrafted cisplatin-sensitive and cisplatin-resistant tumor models [3]
\nMice were transplanted with fragments of OVAX1 and OVAX1R tumors, and when tumors reached a homogeneous palpable size were randomly allocated into the treatment groups (n = 8–12/group): i) Placebo; ii) Lurbinectedin (PM01183) (0.18 mg/kg); iii) Cisplatin (3.5 mg/kg); and iv) Lurbinectedin plus cisplatin (0.18 + 3.5 mg/kg). Drugs were i.v. administered once per week for 3 consecutive weeks (days 0, 7, and 14). Seven days after the final dose (day 21), animals were sacrificed, their ovaries dissected out, and weighed. Representative fragments were either frozen in nitrogen or fixed and then processed for paraffin embedding.\n

---

\n\nIn vivo evaluation of synergism among Lurbinectedin (PM01183) and cisplatin treatments [3]
\nFemale mice were subcutaneously implanted with 107 A2780 cells suspended in a 1:1 solution of RPMI-1640:Matrigel. Mice bearing tumors (ca. 150 mm3) were randomly allocated to 13 treatment groups (see Fig. 3 legend). All treatments were intravenously administered once per week for 2 consecutive weeks (days 0 and 7). Tumor growth was recorded 2 to 3 times per week starting from the first day of treatment (day 0) and tumor volume (in mm3), estimated according to the formula V = (a·b2)/2, (a: length or biggest diameter; b: width or smallest diameter). Antitumor drug activity was measured with respect to the T/C index, and the fraction affected (Fa) by treatment was calculated (Fa = 1−T/C). A CI was determined by the CI-isobol method

Absorption, Distribution and Excretion
Following intravenous administration, Cmax and AUC0-inf were 107 µg/L and 551 µgh/L, respectively. No drug accumulation was observed between dosing intervals (every 3 weeks). No significant differences in absorption were observed across different populations (e.g., based on age, sex, ethnicity, etc.), but rubinekine has not been studied in patients with severe renal impairment or moderate/severe hepatic impairment. Approximately 89% of the administered dose is excreted in feces (<0.2% unchanged) and 6% in urine (1% unchanged). The steady-state volume of distribution for rubinekine is 504 L. The total plasma clearance of rubinekine is approximately 11 L/h. Metabolism/Metabolites Rubinekine is primarily metabolized in vitro via CYP3A4, but specific data on its biotransformation are lacking. An N-demethylated metabolite has been identified in canine subjects.

---

Biological half-life
The terminal half-life of rubinetin is 51 hours.

Hepatotoxicity
Approximately two-thirds of patients receiving rubinetin experience elevated serum transaminase levels, with 4% to 5% experiencing levels exceeding five times the upper limit of normal. Dexamethasone pretreatment appears to reduce the degree and frequency of enzyme elevations. Enzyme elevations typically occur within 2 to 5 days after intravenous infusion, peaking at 5 to 9 days and usually returning to baseline within 2 to 3 weeks. Mild elevations in serum alkaline phosphatase and bilirubin are also common. However, clinically significant liver injury (with jaundice) induced by rubinetin is uncommon. On the other hand, patients with underlying liver disease appear more susceptible to sepsis and multiple organ failure due to chemotherapy; therefore, monitoring of liver function is recommended before and during rubinetin treatment. Severe liver injury often resembles acute decompensation of underlying cirrhosis, manifesting as mild elevations in serum enzymes, worsening jaundice, and impaired hepatic synthesis. Immune hypersensitivity and autoimmune features are uncommon. Death is usually caused by sepsis and multiple organ failure, rather than typical acute liver failure.
Probability Score: D (Possibly the cause of clinically significant liver injury, typically occurring in cases of pre-existing liver disease and high-dose medication use).

---

Protein Binding
Lurbinectedin has a high binding rate (approximately 99%) to serum albumin and α-1-acid glycoprotein in plasma.

[1]. Preclinical Investigations of PM01183 (Lurbinectedin) as a Single Agent or in Combination with Other Anticancer Agents for Clear Cell Carcinoma of the Ovary. PLoS One. 2016 Mar 17;11(3):e0151050.

[2]. PM01183, a new DNA minor groove covalent binder with potent in vitro and in vivo anti-tumour activity. Br J Pharmacol. 2010 Nov;161(5):1099-110.

[3]. Lurbinectedin (PM01183), a new DNA minor groove binder, inhibits growth of orthotopic primary graft of NSC 119875-resistant epithelial ovarian cancer. Clin Cancer Res. 2012 Oct 1;18(19):5399-411.

Lurbinectedin is a DNA alkylating agent that has been investigated for the treatment of various cancers, including mesothelioma, chronic lymphocytic leukemia (CLL), breast cancer, and small cell lung cancer (SCLC). It is a derivative of the marine-derived anticancer drug trabectedin, which is found in extracts of the sea squirt Ecteinascidia turbinata. The main difference between trabectedin and trabectedin is that rubinextin replaces tetrahydroisoquinoline with tetrahydroβ-carboline, thereby enhancing its antitumor activity. On June 15, 2020, the U.S. Food and Drug Administration (FDA) granted rubinextin accelerated approval and orphan drug designation for the treatment of adult patients with metastatic small cell lung cancer whose disease has progressed after platinum-based therapy. This accelerated approval was based on the rate and duration of treatment response observed in ongoing clinical trials and is contingent upon validation of these results in confirmatory trials. Lurbinectedin is an alkylating agent. Lubinedekine's mechanism of action is alkylation activity. Lubinedekine is an antitumor alkylating agent, a synthetic derivative of trabectedine, used to treat refractory metastatic small cell lung cancer. Transient elevations of serum enzymes are common during rubineedekine treatment, and occasionally clinically significant liver damage with jaundice has been observed. Lubinedekine is a synthetic tetrahydropyrrolo[4,3,2-de]quinoline-8(1H)-one alkaloid analog with potential antitumor activity. Lubinedekine covalently binds to residues in the minor groove of DNA, potentially leading to delayed S phase progression, cell cycle arrest at G2/M phase, and cell death. Drug Indications Lubinedekine is indicated for the treatment of adult patients with metastatic small cell lung cancer (SCLC) whose disease has progressed after platinum-based chemotherapy. Treatment of Malignant Mesothelioma Treatment of Small Cell Lung Cancer Mechanism of Action Lubinedekine is a DNA alkylating agent. It covalently binds to guanine residues in the minor groove of DNA, forming an adduct that bends the DNA double helix towards the major groove. This process triggers a series of events that affect transcription factor activity and impair DNA repair pathways, ultimately leading to double-strand DNA breaks and cell death. Other mechanisms of action include inhibition of RNA polymerase II activity, inactivation of Ewing's sarcoma oncoprotein (EWS-FL11) through nuclear redistribution, and inhibition of human monocyte activity and macrophage infiltration into tumor tissue.

---

Pharmacodynamics
Rubinekine exerts its chemotherapeutic activity by covalently binding to DNA, leading to DNA double-strand breaks and subsequently cell death. Rubinekine is associated with myelosuppression; patients receiving this drug should be closely monitored for signs of cytopenia. Before starting treatment, a baseline neutrophil count >1,500/mm³ and a platelet count >100,000/mm³ should be ensured. If the neutrophil count is below 500/mm³, supplementation with granulocyte colony-stimulating factor (G-CSF) should be considered. Lubitidine is also associated with hepatotoxicity. Liver function should be monitored regularly at baseline and throughout treatment, and treatment should be paused, reduced, or permanently discontinued depending on the severity of observed hepatotoxicity.

---

Objective: This study aimed to evaluate the antitumor effects of lumbitidine as monotherapy or in combination with existing anticancer drugs for clear cell ovarian carcinoma (CCC). Clear cell ovarian carcinoma is considered a highly aggressive, chemotherapy-resistant histological subtype. Methods: Using human clear cell ovarian cancer cell lines, the antitumor effects of lumbitidine, SN-38, doxorubicin, cisplatin, and paclitaxel as monotherapy were evaluated using the MTS assay. Subsequently, we used equivalence line plot analysis to evaluate the antitumor effects of combination therapies containing lumbitidine with one of the other four drugs to test for synergistic effects. We also examined the antitumor activity of each treatment regimen using cisplatin-resistant and paclitaxel-resistant CCC sublines. Finally, we determined the effect of mTORC1 inhibitors on the antitumor activity of lumbitidine-based chemotherapy. Results: Lubinetidine exhibited significant antitumor activity against both chemotherapeutic and resistant CCC cells in vitro. In a mouse CCC cell xenograft model, lumbinetidine significantly inhibited tumor growth. Among the tested combinations, lumbinetidine combined with SN-38 produced a significant synergistic effect. This combination also showed a strong synergistic effect against cisplatin- and paclitaxel-resistant CCC cell lines. Everolimus significantly enhanced the antitumor activity of lumbinetidine-based chemotherapy drugs. Conclusion: Lubinetidine is a novel drug targeting active transcription, demonstrating antitumor activity as monotherapy for clear cell carcinoma (CCC) and a synergistic antitumor effect when combined with irinotecan. Our results suggest that lumbinetidine is a promising treatment for ovarian clear cell carcinoma, both as a first-line therapy and as salvage therapy for recurrent lesions after platinum- or paclitaxel treatment. [1]

---

Background and Objectives: PM01183 is a novel synthetic tetrahydroisoquinoline alkaloid currently in Phase I clinical development for the treatment of solid tumors. This study characterized the interaction of PM01183 with specific DNA sequences and its in vitro and in vivo cytotoxicity. Experimental Methods: The DNA binding characteristics of PM01183 were investigated using electrophoretic mobility shift analysis, fluorescence melting kinetics, and computational modeling. Its mechanism of action was investigated using flow cytometry, Western blotting, and fluorescence microscopy. In vitro antitumor activity was determined by the MTT assay, and in vivo activity was evaluated using various human cancer models. Main Results: Electrophoretic mobility shift analysis showed that PM01183 can bind to DNA. Fluorescence thermodenaturation experiments showed that the DNA triplet sequences most favorable for forming covalent adducts were AGC, CGG, AGG, and TGG, all of which are guanine-centered. Molecular modeling can explain these binding preferences. PM01183-DNA adducts can cause double-strand breaks in living cells, thereby triggering S-phase cell accumulation and apoptosis. In a cell line containing 23 cell lines, PM01183 showed potent cytotoxic activity with an average GI50 value of 2.7 nM. In four human cancer mouse xenograft models, PM01183 significantly inhibited tumor growth without causing weight loss in the test animals. Conclusion and significance: PM01183 can bind to specific DNA sequences and promote apoptosis by inducing double-strand breaks at nanomolar concentrations. The potent antitumor activity of PM01183 in multiple human cancer mouse models supports its development as a novel antitumor drug. [2] Objective: Epithelial ovarian cancer (EOC) is the fifth leading cause of death from gynecological malignancies in women. The low survival rate of ovarian cancer is due to its advanced stage at diagnosis and intrinsic or acquired resistance to standard platinum-based chemotherapy. Therefore, the development of effective and innovative treatment strategies to overcome cisplatin resistance remains an urgent priority. Experimental Design: To investigate novel treatment methods in an in vivo model simulating ovarian cancer tumor growth, we constructed a preclinical model of ovarian cancer by orthotopic transplantation of primary serous tumors into nude mice. Furthermore, we successfully constructed a corresponding acquired cisplatin-resistant tumor model in mice. We evaluated the efficacy of lurbinectedin (PM01183), a novel marine-derived DNA minor groove covalent binder, as a single agent and in combination with cisplatin in both preclinical models. Results: The orthotopically transplanted tumor tissue mimicked the histopathological features of primary patient tumors and reproduced the tumor response to cisplatin treatment in mice. We demonstrated that lurbinectedin alone or in combination with cisplatin was effective in treating both cisplatin-sensitive and cisplatin-resistant preclinical ovarian tumor models. Moreover, the combination therapy exhibited the strongest synergistic effect in vivo, especially in cisplatin-resistant tumors. Lubinectedin's inhibition of tumor growth was associated with reduced cell proliferation, increased aberrant mitotic rates, and subsequent induced apoptosis. Conclusion: In summary, the preclinical orthotopic ovarian tumor transplantation model is an effective tool for drug development, providing conclusive evidence that rubinede can become an effective treatment for epithelial ovarian cancer by overcoming cisplatin resistance. [3]

C41H44N4O10S

784.88

784.278

C, 62.74; H, 5.65; N, 7.14; O, 20.38; S, 4.08

497871-47-3

Lurbinectedin-d3

57327016

White to light yellow solid powder

4.393

4

14

4

56

1530

7

S1C[C@@]2(C3=C(C4C=C(C=CC=4N3)OC)CCN2)C(=O)OC[C@@]2([H])C3=C4C(=C(C)C(=C3[C@]1([H])[C@@]1([H])[C@@]3([H])C5C(=C(C(C)=CC=5C[C@@]([H])([C@@H](N12)O)N3C)OC)O)OC(C)=O)OCO4

YDDMIZRDDREKEP-HWTBNCOESA-N

InChI=1S/C41H44N4O10S/c1-17-11-20-12-25-39(48)45-26-14-52-40(49)41(38-22(9-10-42-41)23-13-21(50-5)7-8-24(23)43-38)15-56-37(31(45)30(44(25)4)27(20)32(47)33(17)51-6)29-28(26)36-35(53-16-54-36)18(2)34(29)55-19(3)46/h7-8,11,13,25-26,30-31,37,39,42-43,47-48H,9-10,12,14-16H2,1-6H3/t25-,26-,30+,31+,37+,39-,41+/m0/s1

[(1R,2R,3R,11S,12S,14R,26R)-5,12-dihydroxy-6,6'-dimethoxy-7,21,30-trimethyl-27-oxospiro[17,19,28-trioxa-24-thia-13,30-diazaheptacyclo[12.9.6.13,11.02,13.04,9.015,23.016,20]triaconta-4(9),5,7,15,20,22-hexaene-26,1'-2,3,4,9-tetrahydropyrido[3,4-b]indole]-22-yl] acetate

PM-01183; 497871-47-3; Tryptamicidin; Zepzelca; PM01,183; zepsyre; PM-01,183; lurbinectedina; PM01183; Lurbinectedin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~20 mg/mL (~25.48 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

---

Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

View More

Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

---

Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

View More

Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

---

Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

---

 (Please use freshly prepared in vivo formulations for optimal results.)