Enzalutamide is a drug used to treat prostate cancer (PC) and docetaxel is a drug for chemotherapeutic treatment of diverse cancer types, including PC. The effectiveness of these drugs in treating castration-resistant prostate cancer (CRPC) is poor and therefore CRPC is still largely incurable. However, the bio-inhibitor of fatty acid-binding protein 5 (FABP5), dmrFABP5, which is a mutant form of FABP5 incapable of binding to fatty acids, has been shown recently to be able to suppress the tumorigenicity and metastasis of cultured CRPC cells. The present study investigated the possible synergistic effect of dmrFABP5 combined with either enzalutamide or docetaxel on suppressing the tumorigenic properties of PC cells, including cell viability, migration, invasion and colony proliferation in soft agar. A highly significant synergistic inhibitory effect on these properties was observed when dmrFABP5 was used in combination with enzalutamide on androgen-responsive PC 22RV1 cells. Moreover, a highly significant synergistic inhibitory effect was also observed when dmrFABP5 was combined with docetaxel, and added to 22RV1 cells and to the highly malignant, androgen-receptor (AR)-negative Du145 cells. DmrFABP5 alone failed to produce any suppressive effect when added to the FABP5-negative cell line LNCaP, although enzalutamide could significantly suppress LNCaP cells when used as a single agent. These synergistic inhibitory effects of dmrFABP5 were produced by interrupting the FABP5-related signal transduction pathway in PC cells. Thus, dmrFABP5 appears to be not only a potential single therapeutic agent, but it may also be used in combination with existing drugs to suppress both AR-positive and AR-negative PC.

PDF file - 1.3MB, Proliferation of MDA MB231 and A549 cells grown in different conditions.

Table S1 MMPs/ S100A4, Table 2 Survival Times, Table S3 Cox Results, Table S4 2x2 Tables, Table S5 Logistic Association , Table S6 Same Area Staining.

PDF file - 3.5, MTT assay showing that cancer cells with K-Ras activation mutation (HCT116/Hkh-2 and DLD1/DKO3 isogenic pairs) and c-Met (HCC827 parental/GR5 pair) are more susceptible to Ran silencing-induced apoptosis. (A) In HCT116/Hkh-2 colon cancer isogenic pair, HCT116 cells, which contain K-Ras activation mutation, are more susceptible to apoptosis induction by the 5 shRNAs targeting Ran, compared to the K-Ras wild-type counterpart, Hkh-2. (B) In DLD1/DKO3 colon cancer isogenic pair, DLD1 cells, which contain K-Ras activation mutation, are more susceptible to apoptosis induction by the 2 shRNAs targeting Ran, compared to the K-Ras wild-type counterpart, DKO3. (C) In HCC827 parental/GR5 lung cancer pair, the GR5 cells, which contain c-Met amplification, are more susceptible to apoptosis induction by the 2 shRNAs targeting Ran, compared to the wild-type HCC827 cells. Results are plotted as histogram showing the mean SD from three independent experiments. Key; *, ** and *** represent p < 0.05, <0.01 and <0.001, respectively. Representative blots from three independent experiments are shown.

Fatty acid‑binding protein 5 (FABP5) and androgen receptor (AR) are critical promoters of prostate cancer. In the present study, the effects of knocking out the FABP5 or AR genes on malignant characteristics of prostate cancer cells were investigated, and changes in the expression of certain key proteins in the FABP5 (or AR)‑peroxisome proliferator activated receptor‑γ (PPARγ)‑vascular endothelial growth factor (VEGF) signaling pathway were monitored. The results obtained showed that FABP5‑ or AR‑knockout (KO) led to a marked suppression of the malignant characteristics of the cells, in part, through disrupting this signaling pathway. Moreover, FABP5 and AR are able to interact with each other to regulate this pathway, with FABP5 controlling the dominant AR splicing variant 7 (ARV7), and AR, in return, regulates the expression of FABP5. Comparisons of the RNA profiles revealed the existence of numerous differentially expressed genes (DEGs) comparing between the parental and the FABP5‑ or AR‑KO cells. The six most abundant changes in DEGs were found to be attributable to the transition from androgen‑responsive to androgen‑unresponsive, castration‑resistant prostate cancer (CRPC) cells. These findings have provided novel insights into the complex molecular pathogenesis of CRPC cells, and have demonstrated that interactions between FABP5 and AR contribute to the transition of prostate cancer cells to an androgen‑independent state. Moreover, gene enrichment analysis revealed that the most highly enriched biological processes associated with the DEGs included those responsive to fatty acids, cholesterol and sterol biosynthesis, as well as to lipid and fatty acid transportation. Since these pathways regulated by FABP5 or AR may be crucial in terms of transducing signals for cancer cell progression, targeting FABP5, AR and their associated pathways, rather than AR alone, may provide a new avenue for the development of therapeutic strategies geared towards suppressing the malignant progression to CRPC cells.

Purpose: Existing prognostic biomarkers are inadequate for stratifying breast cancer patients with the highest risk of tumor progression at the time of diagnosis. Here, we demonstrate that the small GTPase Ran has predictive value for breast cancer (BC) patients as a whole, and for specific BC subtypes.Patients and methods: Ran expression was quantified by immunohistochemistry in 263 patients with primary breast cancer diagnosed at the Breast Unit, Royal Liverpool Hospital. Additionally as an independent validation, we also analyzed the mRNA expressions of Ran, ER, PR, and Cerb-2, the triple-negative endocrine receptors, and their associations with patient survival in a combined patient cohorts of multiple public datasets (n = 1079). We analyzed the data with Spearman's rank correlation and Kaplan-Meier plots coupled with Wilcoxon-Gehan tests, respectively. All statistical tests were two-sided.Results: Ran nuclear, cytoplasmic, and total staining are substantially associated with poor survival, independent of conventional prognostic markers such as estrogen receptor (ER), human epidermal growth factor receptor 2 (HER2), and lymph node status. According to the datasets, Ran was significantly correlated with distant metastasis-free survival (DMFS) and relapse-free survival (RFS).Conclusion: We found that Ran expression is a unique predictive biomarker for patient survival, metastasis, and tumor relapse. This biomarker could be used for diagnostic purposes, using formalin-fixed, paraffin-embedded tumor biopsy samples from breast cancer patients in the early stages.

PDF file - 1.9MB, Ran silencing induced apoptosis is concentration dependent. Effect of Ran silencing on apoptotic induction was tested using five different shRNAs (shRan1-5) targeting different regions of Ran compared to scramble shRNA (shScr) control in MDA MB231 breast cancer and A549 lung cancer cells. (A) mRNA and (B) protein levels of Ran, and (C) Flow cytometric analysis for DNA content, in MDA MB231 cells infected with different shRNAs targeting Ran. (D) Protein level and (E) Flow analysis for DNA content in A549 cells infected with different shRNAs targeting Ran. Note that the decrease in Ran mRNA level was associated with the decrease in Ran protein levels (r = 0.950, p < 0.01) in MDA MB231 cells infected with shRan1-5. In addition, the percentage of sub-G1 phase apoptotic cells induced by Ran silencing was significantly inversely associated with the levels of Ran in protein levels in MDA MB231 breast cancer cells (r = -0.880, p <0.05). Similar results were obtained in A549 cells.

PDF file - 1.8K, Percentage of sub-G1 phase apoptotic cells and apoptotic pathway induced by Ran silencing in different cell lines. (A) Cells were harvested 72 hours post-infection, fixed and stained with Propidium iodide. Significantly fewer Sub-G1 phase apoptotic cells were observed in the immortalized human embryonic kidney 293 (HEK 293) cell line compared to cancer cell lines from breast (MDA MB231), lung (A549), prostate (DU145), esophageal (EC109) and colon (HCT116 and DLD-1) upon Ran silencing (p < 0.01). (B) Western blots of apoptosis mediators in immortalized HEK293, breast (MDA MB231), lung (A549), prostate (DU145), esophageal (EC109) and colon (DLD-1 and HCT116) cancer cell lines at 72 hours post-infection with Scr or Ran shRNAs.

supplemental materials and methods.

Background Brain metastases are the most common intracranial tumors with an increasing incidence. They are an important cause of morbidity and mortality in patients with solid organ cancer and a focus of recent clinical research and experimental interest. Immune checkpoint inhibitors are being increasingly used to treat solid organ cancers. Methods To determine whether immune checkpoint inhibitors were biologically effective in the brain, we compared melanoma brain metastasis samples where treatment with ipilimumab had occurred preoperatively to those who had not received any immune modulating therapy and looked for histopathological (invasion, vascularity, metastasis inducing proteins, matrix metalloproteinases, immune cell infiltration, tissue architecture) and advanced MRI differences (diffusion weighted imaging). Results Co-localized tissue samples from the same regions as MRI regions of interest showed significantly lower vascularity (density of CD34 + vessels) in the core and higher T-cell infiltration (CD3 + cells) in the leading edge for ipilimumab-treated brain metastasis samples than for untreated cases and this correlated with a higher tumor ADC signal at post-treatment/preoperative MRI brain. Conclusions Treatment of a melanoma brain metastasis with ipilimumab appears to cause measurable biological changes in the tumor that can be correlated with post-treatment diffusion weighted MRI imaging, suggesting both a mechanism of action and a possible surrogate marker of efficacy.

PDF file - 1.5MB, The importance of nucleocytoplasmic transportation and Mcl-1 expression in Ran silencing-induced apoptosis in A549 cells. Cells were grown in different conditions at 24 hours post-infection and were then harvested at 72 hours post-infection. Percentage of sub-G1 phase apoptotic cells are shown in A549 cells treated with (A) rapamycin and/or LMB, and (B) PI103 and/or LMB. Western blots of PARP, Mcl-1 and Ran, in A549 cells expressing various levels of Ran treated with (C) rapamycin and/or LMB, and (D) PI103 and/or LMB. Western blots of various transcription factors in cytoplasmic and nuclear fraction of scramble (Scr) and Ran knockdown (E) A549 cells, (F) A549 cells with or without rapamycin, (G) A549 cells with or without PD184352. (H) Quantitative PCR of Mcl-1 transcript in A549 cells infected with Scr and Ran shRNAs. (I) Western blots of Mcl-1, PARP and Ran at 72hr post-infection of Ran shRNAs in A549 cells grown in Hank's buffered salt solution (HBSS), serum-free and serum-supplemented conditions. (J) Quantification of Mcl-1 protein levels from figure (I). (K) Western blots of PARP, Mcl-1 and Bcl-2 in MDA MB231 cells upon Ran silencing in the presence of different inhibitors. (L) Quantification of Mcl-1 protein levels from figure.

PDF file - 13.3MB, High level of Ran is correlated with shorter survival time of lung cancer patients.(A) Representative images for IHC staining in lung cancer specimens. Lung cancer specimens stained with different patterns for Ran. Upper panel, 40x magnification; Lower panel, 200x magnification of the same cases. (B) Kaplan-Meier plot of the survival of lung cancer patients using combined nuclear and cytoplasmic expression of Ran; High level, high level expression of both nuclear and cytoplasmc Ran; Intermediate level, high level expression of either nuclear or cytoplasmic Ran; Low level, low level expression of both nuclear and cytoplasmic Ran. Cumulative proportion of lung cancer patients surviving with time is plotted for high, intermediate and low Ran groups. (C) Kaplan-Meier plot of survival of lung cancer patients from seven microarray datasets available in GEO database. Cumulative proportion of lung cancer patients surviving with time is plotted for high (top 25% of patients expressing a high level of Ran) and low (bottom 25% of patients expressing a low level of Ran) Ran groups.

PDF file - 4.8, Effect of chemical inhibitors on the activity of signaling pathways in MDA MB231 and A549 cells expressing various levels of Ran. Western blots of phospho- and total Akt, ERK and S6K proteins in MDA MB231 and A549 cells expressing various levels of Ran grown in different growth conditions. Representative blots from two independent experiments are shown.

Most patients who die of cancer do so from its metastasis to other organs. The calcium-binding protein S100A4 can induce cell migration/invasion and metastasis in experimental animals and is overexpressed in most human metastatic cancers. Here, we report that a novel inhibitor of S100A4 can specifically block its increase in cell migration in rat (IC50, 46 µM) and human (56 µM) triple negative breast cancer (TNBC) cells without affecting Western-blotted levels of S100A4. The moderately-weak S100A4-inhibitory compound, US-10113 has been chemically attached to thalidomide to stimulate the proteasomal machinery of a cell. This proteolysis targeting chimera (PROTAC) RGC specifically eliminates S100A4 in the rat (IC50, 8 nM) and human TNBC (IC50, 3.2 nM) cell lines with a near 20,000-fold increase in efficiency over US-10113 at inhibiting cell migration (IC50, 1.6 nM and 3.5 nM, respectively). Knockdown of S100A4 in human TNBC cells abolishes this effect. When PROTAC RGC is injected with mouse TNBC cells into syngeneic Balb/c mice, the incidence of experimental lung metastases or local primary tumour invasion and spontaneous lung metastasis is reduced in the 10–100 nM concentration range (Fisher’s Exact test, p ≤ 0.024). In conclusion, we have established proof of principle that destructive targeting of S100A4 provides the first realistic chemotherapeutic approach to selectively inhibiting metastasis.

PDF file - 3.6K, Cancer cells with K-Ras activation mutation (HCT116/Hkh-2 isogenic pair) are more susceptible to Ran silencing-induced apoptosis.

<p>Fig S1 Whole Mounts, Fig S2 Westerns, Fig S3 Male/Female Bsk, Fig S4 Inhibitors, Fig S5 Breast Tumors, Fig S6 MMP2 + Other, Fig S7 MMP2/S100A4, Supp Methods, Figure 5 Legend.</p>

PDF file - 1.6MB, Percentage of sub-G1 phase apoptotic MCF10a and MDA MB231 cells grown in serum-containing medium after Ran silencing. (A-B) Cells were infected with shRan1 and shRan2. Medium was changed to serum-free medium (DMEM) 24hr post-infection. Cells were harvested at 72hr and 96hr post-infection for (A) cell cycle and (B) Western blot analyses. (A) Significantly more sub-G1 phase cells were observed in MDA MB231 breast cancer cells than in immortalized breast epithelial cells 72 and 96 hr post-infection of the shRNAs. (B) More cleaved PARP, caspase 9 and caspase 3 were observed in MDA MB231 than in MCF10A cells upon Ran silencing, suggesting a higher apoptotic response in MDA MB231 than in MCF10a cells. Levels of Ran knockdown were similar in both cell lines. Actin was used as a loading control. (C-D) Cells were infected with shRan1 and shRan2, and harvested 72hr post-infection for (C) cell cycle and (D) Western blot analyses. (C) More apoptotic cells were observed in MDA MB231 than MCF10a cells upon Ran-silencing 72hr post-infection of shRNAs, when these two cell lines were grown in their normal medium. (D) Higher levels of cleaved PARP, caspase 9 and caspase 3 were observed at 72hr post-infection of shRNAs. Results are plotted as histogram showing the mean SD from three independent experiments. Key; * represents p < 0.05 and ** represents p <0.01.

supplementary data on IHC stains and image files