Profiling the heterogeneity of colorectal cancer consensus molecular subtypes using spatial transcriptomics.

The consensus molecular subtypes (CMS) of colorectal cancer (CRC) is the most widely-used gene expression-based classification and has contributed to a better understanding of disease heterogeneity and prognosis. Nevertheless, CMS intratumoral heterogeneity restricts its clinical application, stressing the necessity of further characterizing the composition and architecture of CRC. Here, we used Spatial Transcriptomics (ST) in combination with single-cell RNA sequencing (scRNA-seq) to decipher the spatially resolved cellular and molecular composition of CRC. In addition to mapping the intratumoral heterogeneity of CMS and their microenvironment, we identified cell communication events in the tumor-stroma interface of CMS2 carcinomas. This includes tumor growth-inhibiting as well as -activating signals, such as the potential regulation of the ETV4 transcriptional activity by DCN or the PLAU-PLAUR ligand-receptor interaction. Our study illustrates the potential of ST to resolve CRC molecular heterogeneity and thereby help advance personalized therapy.

Characterization of Breast Cancer Preclinical Models Reveals a Specific Pattern of Macrophage Polarization.

Drug discovery efforts have focused on the tumor microenvironment in recent years. However, few studies have characterized the stroma component in patient-derived xenografts (PDXs) and genetically engineered mouse models (GEMs). In this study, we characterized the stroma in various models of breast cancer tumors in mice. We performed transcriptomic and flow cytometry analyses on murine populations for a series of 25 PDXs and the two most commonly used GEMs (MMTV-PyMT and MMTV-erBb2). We sorted macrophages from five models. We then profiled gene expression in these cells, which were also subjected to flow cytometry for phenotypic characterization. Hematopoietic cell composition, mostly macrophages and granulocytes, differed between tumors. Macrophages had a specific polarization phenotype related to their M1/M2 classification and associated with the expression of genes involved in the recruitment, invasion and metastasis processes. The heterogeneity of the stroma component of the models studied suggests that tumor cells modify their microenvironment to satisfy their needs. Our observations suggest that such models are of relevance for preclinical studies.

Predictive gene signature of response to the anti-TweakR mAb PDL192 in patient-derived breast cancer xenografts.

PURPOSE: (1) To determine TweakR expression in human breast cancers (BC), (2) evaluate the antitumor effect of the anti-TweakR antibody PDL192, used alone or after chemotherapy-induced complete remission (CR), on patient-derived BC xenografts (PDX) and (3) define predictive markers of response. EXPERIMENTAL DESIGN: TweakR expression was analyzed by IHC on patients and PDXs BC samples. In vivo antitumor effect of PDL192 was evaluated on eight TweakR-positive BC PDXs alone or after complete remission induced by a combination of doxorubicin and cyclophosphamide. Using both responding and resistant PDX tumors after PDL192 administration, RT-QPCR were performed on a wide list of selected candidate genes to identify predictive markers of response. RESULTS: TweakR protein was expressed in about half of human BC samples. In vivo PDL192 treatment had significantly anti-tumor activity in 4 of 8 TweakR-positive BC PDXs, but no correlation between the expression level of the Tweak receptor and response to therapy was observed. PDL192 also significantly delayed tumor relapse after CR. Finally, an 8 gene signature was defined from sensitive and resistant PDXs. CONCLUSIONS: PDL192 was highly efficient in some BC PDXs. We found 8 genes that were differentially expressed in responding and resistant tumors and could constitute a gene expression signature which would need to be extended to other xenograft models for confirmation. These data confirm the therapeutic potential of TweakR targeting in BC and the possibility of prospectively selecting patients who might benefit from therapy.

TTK/hMPS1 is an attractive therapeutic target for triple-negative breast cancer.

Triple-negative breast cancer (TNBC) represents a subgroup of breast cancers (BC) associated with the most aggressive clinical behavior. No targeted therapy is currently available for the treatment of patients with TNBC. In order to discover potential therapeutic targets, we searched for protein kinases that are overexpressed in human TNBC biopsies and whose silencing in TNBC cell lines causes cell death. A cohort including human BC biopsies obtained at Institut Curie as well as normal tissues has been analyzed at a gene-expression level. The data revealed that the human protein kinase monopolar spindle 1 (hMPS1), also known as TTK and involved in mitotic checkpoint, is specifically overexpressed in TNBC, compared to the other BC subgroups and healthy tissues. We confirmed by immunohistochemistry and reverse phase protein array that TNBC expressed higher levels of TTK protein compared to the other BC subgroups. We then determined the biological effects of TTK depletion by RNA interference, through analyses of tumorigenic capacity and cell viability in different human TNBC cell lines. We found that RNAi-mediated depletion of TTK in various TNBC cell lines severely compromised their viability and their ability to form colonies in an anchorage-independent manner. Moreover, we observed that TTK silencing led to an increase in H2AX phosphorylation, activation of caspases 3/7, sub-G1 cell population accumulation and high annexin V staining, as well as to a decrease in G1 phase cell population and an increased aneuploidy. Altogether, these data indicate that TTK depletion in TNBC cells induces apoptosis. These results point out TTK as a protein kinase overexpressed in TNBC that may represent an attractive therapeutic target specifically for this poor prognosis associated subgroup of breast cancer.

Polo-like kinase 1: a potential therapeutic option in combination with conventional chemotherapy for the management of patients with triple-negative breast cancer.

Breast cancers are composed of molecularly distinct subtypes with different clinical outcomes and responses to therapy. To discover potential therapeutic targets for the poor prognosis-associated triple-negative breast cancer (TNBC), gene expression profiling was carried out on a cohort of 130 breast cancer samples. Polo-like kinase 1 (PLK1) was found to be significantly overexpressed in TNBC compared with the other breast cancer subtypes. High PLK1 expression was confirmed by reverse phase protein and tissue microarrays. In triple-negative cell lines, RNAi-mediated PLK1 depletion or inhibition of PLK1 activity with a small molecule (BI-2536) induced an increase in phosphorylated H2AX, G(2)-M arrest, and apoptosis. A soft-agar colony assay showed that PLK1 silencing impaired clonogenic potential of TNBC cell lines. When cells were grown in extracellular matrix gels (Matrigel), and exposed to BI-2536, apoptosis was observed specifically in TNBC cancerous cells, and not in a normal cell line. When administrated as a single agent, the PLK1 inhibitor significantly impaired tumor growth in vivo in two xenografts models established from biopsies of patients with TNBC. Most importantly, the administration of BI-2536, in combination with doxorubicin + cyclophosphamide chemotherapy, led to a faster complete response compared with the chemotherapy treatment alone and prevented relapse, which is the major risk associated with TNBC. Altogether, our observations suggest PLK1 inhibition as an attractive therapeutic approach, in association with conventional chemotherapy, for the management of patients with TNBC.

Group acupuncture for knee pain: evaluation of a cost-saving initiative in the health service.

BACKGROUND: Acupuncture has been provided in nurse-led group clinics in St Albans since 2008. It is funded by a commissioning group within the National Health Service, on a trial basis, for patients with knee osteoarthritis who would otherwise be referred to an orthopaedic surgeon. AIM: To evaluate the patients seen in the service's first year of operation and their outcome up to the end of 2010. METHODS: Service evaluation was made of patient data from the referral centre and the acupuncture clinics, including baseline characteristics, attendance data and Measure Yourself Medical Outcome Profile (MYMOP) symptom, function and well-being scores over at least 2 years. RESULTS: 114 patients were offered acupuncture, of whom 90 patients were assessed in the acupuncture clinics. 41 of these were still attending after 1 year and 31 (34%) after 2 years. MYMOP scores showed clinically significant improvements at 1 month for pain (4.2 (SD 1.2) to 2.9 (SD 1.4)), stiffness (4.1 (SD 1.3) to 2.9 (SD 1.3)) and function (4.5 (SD 1.1) to 3.3 (SD 1.2)) which continued up to 2 years. Well-being scores did not change. CONCLUSIONS: This is the first evaluation of nurse-led group (multibed) acupuncture clinics for patients with knee osteoarthritis to include a 2 year follow-up. It shows the practicability of offering a low-cost acupuncture service as an alternative to knee surgery and the service's success in providing long-term symptom relief in about a third of patients. Using realistic assumptions, the cost consequences for the local commissioning group are an estimated saving of £100 000 a year. Sensitivity analyses are presented using different assumptions.

The fibroblast growth factor receptor 1 (FGFR1), a marker of response to chemoradiotherapy in breast cancer?

The goal of the present study was to evaluate the role of the tyrosine kinase receptor fibroblast growth factor-1 (FGFR1) and its ligand, the fibroblast growth factor 2 (FGF2) in determining the response to chemoradiotherapy of breast cancers. S14 was a phase II neoadjuvant study carried out at the Institut Curie that recruited 59 patients between November 2001 and September 2003. This prospective study aimed to assess the pathological response after preoperative radiochemotherapy (5FU-Navelbine-radiotherapy) for large breast cancers. The expression of FGFR1 and FGF2 in tumor cells were assessed by immunohistochemistry. Tumors in which no staining was seen, were considered as negative for that protein. We used the Khi-2 test or the Fisher test to compare the qualitative variables and the Student t test or the non-parametric Wilcoxon test for the quantitative variables. We included in the present study all the 32 patients from the S14 cohort for whom the tissue blocks from the biopsy specimens were available with sufficient tumoral tissue. FGFR1 and FGF2 staining were observed respectively in 17 (56%) and 22 (68%) of the 32 tumoral biopsies. The expression of FGFR1 was associated with the hormone receptor positive status (p=0.0191). Only 11% (1/9) of the high grade tumors failed to respond to chemoradiotherapy compared to 68 % resistant tumors (15/22) among the low/intermediate grade tumors (p=0.0199). Among the low/intermediate grade tumors, FGFR1 negative tumors did not respond to chemoradiotherapy (0/9), compared with tumors expressing FGFR1 among which, almost one half had a good response (6/13) (p=0.0167). Among the low and intermediate grade breast cancers, the FGFR1 negative tumors were resistant to chemoradiotherapy. The expression of FGFR1 in patients' biopsies may serve as a marker of response to chemoradiotherapy.

Oxidative stress promotes myofibroblast differentiation and tumour spreading.

JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative stress resulting from junD deletion to examine the role of reactive oxygen species (ROS) in tumour development. In a model of mammary carcinogenesis, junD inactivation increased tumour incidence and revealed an associated reactive stroma. junD-inactivation in the stroma was sufficient to shorten tumour-free survival rate and enhance metastatic spread. ROS promoted conversion of fibroblasts into highly migrating myofibroblasts through accumulation of the hypoxia-inducible factor (HIF)-1alpha transcription factor and the CXCL12 chemokine. Accordingly, treatment with an antioxidant reduced the levels of HIF and CXCL12 and numerous myofibroblast features. CXCL12 accumulated in the stroma of HER2-human breast adenocarcinomas. Moreover, HER2 tumours exhibited a high proportion of myofibroblasts, which was significantly correlated to nodal metastases. Interestingly, this subset of tumours exhibited a significant nuclear exclusion of JunD and revealed an associated oxido-reduction signature, further demonstrating the relevance of our findings in human cancers. Collectively, our data uncover a new mechanism by which oxidative stress increases the migratory properties of stromal fibroblasts, which in turn potentiate tumour dissemination.

Electric powered wheelchairs for those with muscular dystrophy: problems of posture, pain and deformity.

PURPOSE: To identify areas of difficulty encountered by a regional wheelchair service in providing Electric Powered Indoor/outdoor wheelchairs (EPIOCs) to those with muscular dystrophy (MD) in the early years of their provision--particularly posture, pain and deformity. METHOD: Wheelchair service records of all users between April 1997 and March 2000 were reviewed retrospectively and issues relating to weakness, pain/discomfort, deformities, other medical issues, weight change, function, posture and driving were documented on a purpose-designed proforma. Adjustments and modifications were documented over the 2-year period following chair delivery. RESULTS: Of 325 EPIOC users on the departmental database, 29 had MD (15 Duchenne's), whose users charts were reviewed. Almost 80% of users needed clinical review within 2 years, mostly due to a scoliosis. Other problems were postural (66%), medical (48%), pain (31%), functional (24%) and weight change (14%). The commonest prescriptions were for specialised seating (24%), lateral supports, headrests and footrests (21% each). CONCLUSIONS: The rate of disease progression was not planned for by the service. Most clients were seen in response to deterioration, rather than anticipating it. Planned reviews within 1 year appear essential for teenagers with MD with the dual issues of rapid maturation and progressive disease.

Setting up an acupuncture knee clinic under Practice Based Commissioning.

This paper outlines the setting up of a new service in primary care offering acupuncture to patients with severe osteoarthritis of the knee. The high volume clinic is funded under the Practice Based Commissioning initiative and is the first of its type in the UK. It appears to offer a model for similar services elsewhere.

Hearing and balance. Part 1--the outer and middle ear.

This article is the first in a four-part series on hearing and balance, continuing our exploration of the senses. It discusses the outer and middle chambers of the ear, whose primary function is to transmit sound to the auditory receptors in the inner ear (Allan, 2005).