Establishment and Morphological Characterization of Patient-Derived Organoids from Breast Cancer

Background

Patient-derived organoids (PDO) technology represents an emerging tool for the study of tumor biology and drug responsiveness, thus being useful to design personalized medicine approaches. Despite several studies and clinical trials are ongoing using PDO from colorectal and pancreatic cancer, only few research papers have been published exploiting PDO from breast cancer. Here, we have developed a new protocol to establish PDO from surgical and biopsy samples. Furthermore, we have set up also the methodologies adopted for culture and morphological evaluations.

Results

Surgical and core biopsy specimens collected from 33 patients with diagnosis of breast cancer have been processed using the protocols here described obtaining PDO from cancerous and healthy mammary tissue (when available) in a quick and easy way with good yields. The more critical aspects influencing the yield were the characteristic of the tissue of origin (healthy vs tumor tissue) and the amount of material obtained after enzymatic digestion process. Success rate from healthy samples was about 20,83%, while this percentage was higher in samples from cancer tissue (i.e. 87,5%). Also the morphological characterization of breast cancer PDO by brightfield and transmission electron microscopy has been reported.

Conclusions

Despite obtaining some organoids from a surgical or biopsy specimen is not a difficult procedure, the establishment of a stable organoid line able to grow and replicate, suitable for long-term biobank storage, is not so obvious. A novel, simple and quick procedure to obtain PDO from surgical and biopsy samples is here proposed to achieve high success rate .

Abstract P1-20-04: Nanoformulation of doxorubicin inside H- ferritin nanocages allows a cardio-safe combined therapy with trastuzumab: De-escalating cardiotoxicity in HER2-positive breast cancer

Background: HER2+ breast cancer (BC) accounts for 20-25 % of BCs and it is characterized by high aggressiveness.1 Despite the anti-HER2 monoclonal antibody Trastuzumab (TZ) has improved BC clinical outcome, it could induce severe cardiac reversible dysfunction:2 HER2 signaling is also essential for growth and survival of myocardiocytes.3 Therefore, the concurrent use of TZ with other cardiotoxic drugs as doxorubicin (DOX) is discouraged.3 Both neoadjuvant and adjuvant clinical trials have challenged the notion that TZ should be administered with anthracyclines only sequentially,4 despite pre-clinical studies demonstrated the significant enhancement of efficacy by their coadministration.5-7 Nanomedicine answers to this clinical issue with HFn-DOX: a natural protein-based DOX nanoformulation with native tumor targeting capability that displays a self-triggered nuclear delivery of DOX improving antitumor efficacy and reducing both chemoresistance and cardiotoxicity.8

Methods: HER2+ BC bearing mice have been treated 5 times twice a week with placebo, HFn-DOX (1 mg/Kg, i.v.), TZ (5 mg/Kg, i.p.) and with the combination of them. Main end-point were cardiotoxicity and anticancer efficacy. Tumor size was measured by caliper, while antitumor activity and cardiotoxicity were characterized by ICH, immunofluorescence, cytofluorimetry, TEM, mass spectrometry and western blot on resections. Statistical analyses were conducted using two-tailed Student's t-test (P< 0.05)

Results: Although single treatments with HFn-DOX or TZ display a good capability to reduce tumor progression, their combination improves antitumor potential, affecting tumor size and angiogenesis. Since the main TZ activity is the induction of the Antibody-Dependent Cell mediated Cytotoxicity, we have assessed the effect of HFn-DOX on Tumor Infiltrating Lymphocytes (TIL), revealing that both TILs enumeration and TIL activity is unaffected by HFn-DOX. On the other hand, HFn-DOX increases the induction of apoptosis, suggesting that the reduction of the tumor size observed in mice treated with the combination of TZ and HFn-DOX is attributable to the coupling of these activity. Mitochondrial morphology has been checked for cardiotoxicity. A pathological increase in mitochondria area coupled with cristae depletion has been evidenced only in mice treated with TZ alone, confirming the overall safety of the HFn-DOX formulation. Interestingly, mice treated with the TZ and HFn-DOX did not display evidences of cardiac suffering. TZ quantification in tumor and heart revealed that the combination with HFn-DOX couples the increased TZ accumulation and penetration in tumor with TZ reduction in heart, resulting in the lack of cardiotoxicity.

Conclusions: Our results suggest that a combined therapy with HFn-DOX and TZ allows an enhanced anticancer activity and reduced cardiotoxicity, with potential translational implications on the treatment of HER2+ BC patients.

[1] Nat Rev Cancer 2009; 9:463; [2] Nat. Med. 2012; 18(11):1639; [3] Cancer treatments reviews 2009; 35:633; [4] The breast 2014; 23:317; [5] Cancer Res. 1998; 58(13):2825; [6] Lancet Oncol. 2011; 12(3):236; [7] Lancet 2010; 375(9712):377. [8] Oncotarget. 2017; 8:8383.

Citation Format: Mazzucchelli S, Andreata F, Bonizzi A, Monieri M, Bellini M, Longhi E, Ottria R, Sorrentino L, Truffi M, Prosperi D, Zerbi P, Corsi F. Nanoformulation of doxorubicin inside H- ferritin nanocages allows a cardio-safe combined therapy with trastuzumab: De-escalating cardiotoxicity in HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-20-04.

Abstract P4-06-09: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Corsi F, Andreata F, Truffi M, Sorrentino L, D'Addio F, Monieri M, Gambaro A, Bellini M, Prosperi D, Mazzucchelli S. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-09.

Abstract P1-10-13: Olaparib nanoformulation in H-ferritin as a promising option for both BRCA-mutated and sporadic triple negative breast cancer: An in vitro study

Background: PolyADP-ribose polymerase (PARP) inhibitors are a novel promising strategy toward triple-negative breast cancer (TNBC), which often shows genomic instability or BRCA mutations. However, clinical results are controversial, and no benefits were demonstrated in case of wild type BRCA, possibly due to poor bioavailability, and inadequate nuclear delivery. Nanotechnology could overcome these major limitations. The aim of this study was to assess the anticancer efficacy of H-Ferritin nanoformulated Olaparib (HOla) vs. free Olaparib (Ola) on BRCA-mutated and non mutated TNBC cells.

Methods: BRCA-mutated HCC1937 cells and BRCA-wild type MDA MB-231 and MDA MB-468 cells were treated with HOla or free Ola in vitro. Active targeting and binding capability of HOla toward transferrin receptor 1 (TfR-1), over-expressed on TNBC cells, was assessed by flow cytometry. Internalization and intracellular localization of Ola and HOla was assessed by confocal microscopy. Anticancer efficacy was assessed by administration of increasing doses of HOla or Ola, comparing cell viability, cell cycle, cell death, PARP-1 cleavage and DNA damage. Finally, anti-PARP efficacy and proportion of drug in the nuclear compartment were compared between treatments.

Results: All TNBC cell lines over-expressed TfR-1 and were succesfully recognized by HOla. Confocal microscopy showed a fast internalization of nanoparticles into cells, with intracellular persistence up to 48h. A marked increase in nuclear concentration of drug was observed with HOla compared to Ola, due to a strongly improved nuclear delivery by H-Ferritin mediated by a self-triggered mechanism. No significant antiproliferative effect was demonstrated with Ola at 10 nM, 50 nM or 100 nM. Conversely, HOla at 50 nM and 100 nM showed a 1000-fold higher anticancer activity in all TNBC cell lines. A possible contribution in cytotoxicity by H-Ferritin nanovector itself was excluded treating cells with void nanoparticles. Proportions of cell cycle arrest in G2/M, cell death, cleaved PARP-1 and DNA damage in terms of phosphorylated histone H2A.X were higher in HOla treated samples than in ones treated with free Ola.

Conclusions:Our findings suggest that nanoformulation of Ola strongly enhances cytotoxic efficacy of PARP inhibition as a stand-alone therapy, on both BRCA-mutated and wild type TNBCs allowing a targeted delivery into TNBC cells and a prompt homing into the nuclear compartment.

Citation Format: Mazzucchelli S, Truffi M, Sorrentino L, Bellini M, Rizzuto MA, Ottria R, Ciuffreda P, Prosperi D, Corsi F. Olaparib nanoformulation in H-ferritin as a promising option for both BRCA-mutated and sporadic triple negative breast cancer: An in vitro study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-13.

Abstract P1-10-11: Multivalent exposure of trastuzumab on iron oxide nanoparticles enhances antitumor activity and weakens drug resistance in HER2+ breast cancer cells

Background: The identification of new strategies aimed to optimize the treatment of breast cancer and its metastases represents a great technical and medical challenge. Target-specific therapies, such as Trastuzumab (TZ), have revolutionized the clinical scenario in certain subsets of cancer. However, the huge variability in response to therapy and the frequent onset of drug resistance in patients still hamper the therapeutic success. Antibody-conjugated nanoparticles may combine specific recognition of tumor cells with the capability to act as innovative reservoir of active drugs. Here, multivalent TZ-conjugated colloidal nanoparticles were developed as target-specific and biologically active nanosystem to enhance the therapeutic potential toward HER2+ breast cancer.

Methods: Iron oxide nanoparticles conjugated with multiple half chains of TZ have been developed and tested in different HER2+ breast cancer cell lines, in comparison to free TZ or untargeted nanoparticles. Active targeting and specificity toward HER2 receptor was assessed by flow cytometry and confocal microscopy. Cellular uptake of nanoparticles and HER2 endocytosis were followed by electron or confocal microscopy. Direct anticancer efficacy was assessed by incubation of free or nanoformulated TZ on sensitive breast cancer cells, and analysis of cell viability, cell cycle, and expression of p27kip1. Finally, nanoparticles were tested on TZ-resistant breast cancer cell lines for capability of re-sensitization.

Results: TZ-conjugated nanoparticles showed specific targeting of HER2, with induction of site-specific phosphorylation in the catalytic domain of the receptor and cellular uptake by endocytosis. Treatment with TZ-conjugated nanoparticles dramatically decreased cancer cell viability, by significantly improving the antitumor activity of TZ. This effect was independent from the ADCC mechanism, and associated with marked induction of p27kip1 expression and cell cycle arrest in G1 phase in TZ-sensitive SKBR-3 cells. TZ-conjugated nanoparticles also affected viability of breast cancer cells insensitive to TZ, further confirming enhanced potential of the nanoformulation and suggesting interference with some mechanisms of resistance.

Conclusions: Our results provide evidence that multivalent exposure of TZ half chain on iron oxide nanoparticles affords enhanced antitumor potential and target-specific activity in HER2+ breast cancer cells. Powerful inhibition of HER2 signaling by TZ-conjugated nanoparticles could favor responsiveness of drug resistant cells, thus suggesting novel therapeutic strategies to overcome resistance.

Citation Format: Truffi M, Monieri M, Sorrentino L, Mazzucchelli S, Colombo M, Pandolfi L, Prosperi D, Corsi F. Multivalent exposure of trastuzumab on iron oxide nanoparticles enhances antitumor activity and weakens drug resistance in HER2+ breast cancer cells [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-11.

Abstract P6-12-17: H-ferritin allows nanometronomic treatment of breast cancer with doxorubicin preventing drug resistance and circumventing cardiotoxicity

Chemotherapeutic treatment of breast cancer is based on maximum tolerated dose (MTD) approach.1 However, advanced stage tumors are not effectively eradicated by MTD owing to suboptimal drug targeting, onset of therapeutic resistance and neoangiogenesis. In contrast, “metronomic” chemotherapy is based on frequent drug administrationsat lower doses, resulting in neovascularization inhibition and induction of tumor dormancy.1,2 However, several limiting factors remain for LDM in order to displace MTD treatments in clinical practice, including 1) low drug accumulation at tumor site,2 2) controversial effectiveness against chemoresistance in advanced metastatic cancers, and 3) acquired resistance after prolonged treatment. Recent advances in nanotechnology could offer groundbreaking solutions to improve the effectiveness of LDM chemotherapy, by taking advantage of the unique targeting efficiency of engineered nanocarriers.3 Here, we propose a new concept of “nanometronomic” chemotherapy, exploiting the H-ferritin (HFn)-mediated targeted delivery of doxorubicin (DOX)in an aggressive and metastatic breast cancer mouse model with DOX-inducible chemoresistance. HFn nanocages naturally target cancer cells4 owing to its affinity for transferrin receptor 1. HFn-DOX was recently demonstrated to overcome chemoresistance by actively promoting DOX nuclear translocation in vitro5,6 and was tested as a MTD treatment on a DOX-sensitive tumor model with encouraging results.7 We find that LDM administration of HFn-DOX strongly improves the antitumor potential of DOX chemotherapy arresting the tumor progression. Indeed, in vitro and in vivo results demonstrate that HFn nanocages mediate the nuclear delivery of DOX and increase DOX accumulation both in tumor tissue and in cancer cell nuclei, resulting in increased efficacy. Moreover, we find that HFn-DOX antitumor effect is attributable to multiple nanodrug actions beyond cell killing, including inhibition of tumor angiogenesis and avoidance of chemoresistance. Otherwise, although an even better reduction of tumor progression was achieved with liposomal DOX (pl-DOX) a five-fold increase in MDR-1-positive cells has been displayed, suggesting that liposomal DOX is not suitable in view of a protracted metronomic treatment, due to the onset of chemoresistance. Multiparametric assessment of heart tissues, including histology, ultrastructural analysis of tissue morphology, and measurement of markers of reactive oxygen species and hepatic/renal conditions, provided evidence that metronomic HFn-DOX allowed us to overcome cardiotoxicity contrary to what is observed with DOX and pl-DOX. Our results suggest that HFn-DOX has tremendous potential for the development of “nanometronomic” chemotherapy toward safe and tailored oncological treatments.

1. Kareva I, et al. Cancer Lett 2015; 358: 100.

2. Kerbel RS. Cancer Res Treat 2007; 39: 150.

3. Cruz-Munoz W, et al. Angiogenesis 2014; 7: 661.

4. Corsi F, Mazzucchelli S. Ther Deliv. 2016; 7: 149.

5. Bellini M, et al.. J Controlled Rel 2014;196: 184.

6. Zhang L, et al. Adv. Healthcare Mat. 2015; 4: 1305.

7. Liang M, et al. Proc Natl Acad Sci USA 2014; 111: 14900.

Citation Format: Mazzucchelli S, Fiandra L, Bellini M, Truffi M, Rizzuto MA, Sorrentino L, Longhi E, Nebuloni M, Prosperi D, Corsi F. H-ferritin allows nanometronomic treatment of breast cancer with doxorubicin preventing drug resistance and circumventing cardiotoxicity [abstract]. In: Proceedings of the Thirty-Ninth Annual CTRC-AACR San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-17.

Retrospective study of 155 cases of prolapse of the nictitating membrane gland in dogs

A retrospective study of 155 cases (114 dogs). The breed, sex and age at the time of the first and opposite onset of nictitans gland prolapse were recorded. Long-term follow-up with a minimum of one-year duration was performed by telephone conversations. One hundred and fourteen dogs representing 155 nictitans gland prolapses were included. 75.4 per cent of the first prolapse occur before one year of age. Unilateral nictitans gland prolapse was observed in 64 per cent of cases. When the condition was bilateral, it occurred simultaneously in 41.4 per cent. When it was bilateral but not simultaneous (24/41), the opposite gland prolapse occurred within three months in 70.8 per cent of the cases. Five breeds were most commonly affected by the bilateral condition: French bulldog, shar pei, great dane, English bulldog and cane corso.

Evidence of distinct tumour-propagating cell populations with different properties in primary human hepatocellular carcinoma

Background and Aims

Increasing evidence that a number of malignancies are characterised by tumour cell heterogeneity has recently been published, but there is still a lack of data concerning liver cancers. The aim of this study was to investigate and characterise tumour-propagating cell (TPC) compartments within human hepatocellular carcinoma (HCC).

Methods

After long-term culture, we identified three morphologically different tumour cell populations in a single HCC specimen, and extensively characterised them by means of flow cytometry, fluorescence microscopy, karyotyping and microarray analyses, single cell cloning, and xenotransplantation in NOD/SCID/IL2Rγ^−/− mice.

Results

The primary cell populations (hcc-1, -2 and -3) and two clones generated by means of limiting dilutions from hcc-1 (clone-1/7 and -1/8) differently expressed a number of tumour-associated stem cell markers, including EpCAM, CD49f, CD44, CD133, CD56, Thy-1, ALDH and CK19, and also showed different doubling times, drug resistance and tumorigenic potential. Moreover, we found that ALDH expression, in combination with CD44 or Thy-1 negativity or CD56 positivity identified subpopulations with a higher clonogenic potential within hcc-1, hcc-2 and hcc-3 primary cell populations, respectively. Karyotyping revealed the clonal evolution of the cell populations and clones within the primary tumour. Importantly, the primary tumour cell population with the greatest tumorigenic potential and drug resistance showed more chromosomal alterations than the others and contained clones with epithelial and mesenchymal features.

Conclusions

Individual HCCs can harbor different self-renewing tumorigenic cell types expressing a variety of morphological and phenotypical markers, karyotypic evolution and different gene expression profiles. This suggests that the models of hepatic carcinogenesis should take into account TPC heterogeneity due to intratumour clonal evolution.

PKC induces internalization and retention of the EAAC1 glutamate transporter in recycling endosomes of MDCK cells

Here we show that stimulation of protein kinase C (PKC) by phorbol 12-myristate 13-acetate (PMA) treatment induces a time-dependent decrease in glutamate transport activity due to relocalization of the excitatory amino acid carrier 1 (EAAC1) glutamate transporter from the apical surface of polarized epithelial Madin-Darby canine kidney (MDCK) cells to intracellular compartments. The PKC-induced internalization of EAAC1 is negatively regulated by the calcineurin inhibitor cyclosporine A and by the expression of a dominant-negative mutant of the endocytic protein dynamin 1, a well-known target of the phosphatase activity of calcineurin. Using 32P-metabolic labeling experiments, we found unchanged levels of phosphorylated EAAC1, indicating that EAAC1 relocalization does not depend on PKC and calcineurin modification of the transporter, while we found that a target of these modifications was the serine778 residue of dynamin, a calcineurin substrate that in its dephosphorylated form activates the endocytic functions of dynamin. These data suggest that PMA stimulates endogenous dynamin and that this activation is required to mediate internalization of EAAC1 in MDCK cells. By immunofluorescence experiments with endosomal markers we demonstrated that internalized EAAC1 accumulates in endosomes also containing the basolateral betaine-GABA transporter BGT1 and activated PKCalpha. The sustained activation of PKC was required to maintain the transporters in the endosomal compartment, while a posttreatment with a PKC-specific inhibitor induced the recycling of the transporters to their appropriate surfaces. Taken together, our data indicate that PKC activity regulates EAAC1 surface density in MDCK cells by inducing its internalization and retention in PKCalpha-labeled recycling endosomes common to apical and basolateral proteins.

[Psychogenic urinary retention in childhood. A severe case treated by an integrated global approach]

Micturating dysfunctions with urinary retention and with diurnal and nocturnal enuresis in children sometimes have a psychogenic genesis. They can appear during the period of development of complete control of micturition. A late recognition of this condition makes the prognosis worse, since high pressure and infections in the urinary tract can cause end-stage renal failure. Here we describe a dramatic case of a 3 year-old boy affected by a psychogenic urine and faecal retention with recurrent pyelonephritis, that was favourably treated for five years by an integrated approach involving clinicians, psychologist, educational and social operators and adoptive parents.