Johan Hartman's Group

Precision pathology and tumor heterogeneity

Breast cancer remains to be the most common malignancy for women in Sweden. Great improvements in screening and adjuvant therapy have led to a current 5-year survival rate of 90%. The individual treatment strategy is based on routine biomarkers on immunohistochemical level; estrogen receptor (ER), progesterone receptor (PR), Her2 and Ki67. ER expression confers strong indications for response to endocrine therapy, whereas patients with Her2-overexpressing tumors can be effectively treated with anti-Her2 therapy. However, such management of breast cancer patients is insufficient to distinguish resistant tumors. We use a variety of methods to identify patterns of drug resistance. Our projects are all of translational character and goes from in vitro experimental models to studies on patient material ex vivo. We are also very interested in the role of tumor-metastatic heterogeneity in relation to drug response.

Next generation breast cancer diagnosis

Group members

Johan Hartman, Professor, Group leader
Emelie Karlsson, Research Coordinator
Stephanie Robertson, MD, PhD, postdoc
Caroline Rönnlund, MD, PhD student
Caroline Schagerholm, MD, PhD student
Qiao Yang, PhD student
Balazs Acs, MD, PhD, Postdoc
Xinsong Chen, Postdoc
Elin Hardell, MD, PhD, Postdoc
Ceren Boyaci, MD, Affiliated

Selected publications

Variability in Breast Cancer Biomarker Assessment and the Effect on Oncological Treatment Decisions: A Nationwide 5-Year Population-Based Study.
Acs B, Fredriksson I, Rönnlund C, Hagerling C, Ehinger A, Kovács A, Røge R, Bergh J, Hartman J
Cancers (Basel) 2021 Mar;13(5):

Predicting molecular phenotypes from histopathology images: a transcriptome-wide expression-morphology analysis in breast cancer.
Wang Y, Kartasalo K, Weitz P, Acs B, Valkonen M, Larsson C, Ruusuvuori P, Hartman J, Rantalainen M
Cancer Res 2021 Aug;():

CD73 immune checkpoint defines regulatory NK cells within the tumor microenvironment.
Neo SY, Yang Y, Record J, Ma R, Chen X, Chen Z, Tobin NP, Blake E, Seitz C, Thomas R, Wagner AK, Andersson J, de Boniface J, Bergh J, Murray S, Alici E, Childs R, Johansson M, Westerberg LS, Haglund F, Hartman J, Lundqvist A
J Clin Invest 2020 03;130(3):1185-1198

Evolutionary history of metastatic breast cancer reveals minimal seeding from axillary lymph nodes.
Ullah I, Karthik GM, Alkodsi A, Kjällquist U, Stålhammar G, Lövrot J, et al
J. Clin. Invest. 2018 Apr;128(4):1355-1370

Estrogen Receptor β as a Therapeutic Target in Breast Cancer Stem Cells.
Ma R, Karthik GM, Lövrot J, Haglund F, Rosin G, Katchy A, et al
J. Natl. Cancer Inst. 2017 03;109(3):1-14

Sequencing-based breast cancer diagnostics as an alternative to routine biomarkers.
Rantalainen M, Klevebring D, Lindberg J, Ivansson E, Rosin G, Kis L, et al
Sci Rep 2016 11;6():38037

Digital image analysis outperforms manual biomarker assessment in breast cancer.
Stålhammar G, Fuentes Martinez N, Lippert M, Tobin NP, Mølholm I, Kis L, et al
Mod. Pathol. 2016 Apr;29(4):318-29

mTOR inhibitors counteract tamoxifen-induced activation of breast cancer stem cells.
Karthik GM, Ma R, Lövrot J, Kis LL, Lindh C, Blomquist L, et al
Cancer Lett. 2015 Oct;367(1):76-87

Digital image analysis in breast pathology-from image processing techniques to artificial intelligence.
Robertson S, Azizpour H, Smith K, Hartman J
Transl Res 2018 04;194():19-35