Recent studies have reported that TUBB3 overexpression is involved in docetaxel (DTX) resistance in prostate cancer (PCa). The aim of this study was to clarify the role of TUBB3 in DTX and cabazitaxel (CBZ) resistance, and cross-resistance between DTX and CBZ in PCa. We analyzed the effect of TUBB3 knockdown on DTX and CBZ resistance and examined the interaction between TUBB3 and PTEN. We also investigated the role of phosphoinositide 3-kinases (PI3K) inhibitor (LY294002) in DTX and CBZ resistance. TUBB3 expression was upregulated in DTX-resistant and CBZ-resistant cells. TUBB3 knockdown re-sensitized DTX-resistant cells to DTX and CBZ-resistant cells to CBZ. Additionally, TUBB3 knockdown re-sensitized DTX-resistant cell lines to CBZ, indicating that TUBB3 mediates cross-resistance between DTX and CBZ. Knockdown of TUBB3 enhanced PTEN expression, and PTEN knockout enhanced TUBB3 expression. LY294002 suppressed TUBB3 expression in DTX-resistant and CBZ-resistant cell lines. LY294002 re-sensitized DTX-resistant cell lines to DTX and CBZ-resistant cell lines to CBZ. These results suggest that TUBB3 is involved in DTX resistance and CBZ resistance. A combination of LY294002/DTX and that of LY294002/CBZ could be potential strategies for PCa treatment.

Fibroblast growth factors (FGFs) and FGF receptors (FGFRs) play an important role in the maintenance of tissue homeostasis and the development and differentiation of prostate tissue through epithelial-stromal interactions. Aberrations of this signaling are linked to the development and progression of prostate cancer (PCa). The FGF family includes two subfamilies, paracrine FGFs and endocrine FGFs. Paracrine FGFs directly bind the extracellular domain of FGFRs and act as a growth factor through the activation of tyrosine kinase signaling. Endocrine FGFs have a low affinity of heparin/heparan sulfate and are easy to circulate in serum. Their biological function is exerted as both a growth factor binding FGFRs with co-receptors and as an endocrine molecule. Many studies have demonstrated the significance of these FGFs and FGFRs in the development and progression of PCa. Herein, we discuss the current knowledge regarding the role of FGFs and FGFRs—including paracrine FGFs, endocrine FGFs, and FGFRs—in the development and progression of PCa, focusing on the representative molecules in each subfamily.

Kinesin family member C1 (KIFC1), a minus end-directed motor protein, is reported to play an essential role in cancer. This study aimed to analyze KIFC1 expression and examine KIFC1 involvement in cisplatin resistance in bladder cancer (BC). Immunohistochemistry showed that 37 of 78 (47.4%) BC cases were positive for KIFC1. KIFC1-positive cases were associated with high T stage and lymph node metastasis. Kaplan-Meier analysis showed that KIFC1-positive cases were associated with poor prognosis, consistent with the results from public databases. Molecular classification in several public databases indicated that KIFC1 expression was increased in basal type BC. Immunohistochemistry showed that KIFC1-positive cases were associated with basal markers 34βE12, CK5 and CD44. KIFC1 expression was increased in altered TP53 compared to that in wild-type TP53. Immunohistochemistry showed that KIFC1-positive cases were associated with p53-positive cases. P53 knockout by CRISPR-Cas9 induced KIFC1 expression in BC cell lines. Knockdown of KIFC1 by siRNA increased the sensitivity to cisplatin in BC cells. Kaplan-Meier analysis indicated that prognosis was poor among KIFC1-positive BC patients treated with cisplatin-based chemotherapy. Immunohistochemistry showed that KIFC1-positive cases were associated with PD-L1-positive cases. High KIFC1 expression was associated with a favorable prognosis in patients treated with atezolizumab from the IMvigor 210 study. These results suggest that KIFC1 might be a promising biomarker and therapeutic target in BC.

Objectives: Previous studies have reported that cases with clinical T1 renal cell cancer upstaging to pathological T3 are a risk factor to predicting postoperative recurrence after partial nephrectomy. The aim of our study was to investigate the impact of the radiological morphology of the enhanced CT scan of clinical T1 renal cell cancer on predicting upstaging to pathological T3.Methods: Three hundred sixty-seven cases with clinical T1 renal cell cancer diagnosed from enhanced CT scans were enrolled in this study. Based on the findings from the enhanced CT scan, the cases were classified into ‘round’, the margins of which were smooth and round; ‘lobular’, one or more findings of smooth dent and no spiky dent were identified on the margin of the tumor; and ‘irregular’, one or more spiky dent were identified on the margin of the tumor. The association of postoperative upstaging with these radiological morphology and other clinical characteristics of each case was analyzed.Results: Eighteen cases (4.9%) pathologically upstaged to T3a. Two round case (0.7%), 3 lobular cases (10.0%) and 13 irregular cases (22.0%) pathologically upstaged (P < 0.001, round + lobular versus irregular). Four of 17 cases (23.5%) with hilar tumors pathologically upstaged, while 14 of 350 cases (4%) with tumors pathologically upstaged in other sites (P < 0.001). Multivariate analysis revealed that irregular case was an independent factor in predicting upstaging to pathological T3a (P < 0.001).Conclusions: Evaluation of the radiological morphology of clinical T1 renal cell cancer based on enhanced CT scans is useful for predicting pathological upstaging.

Ikeguchi M, et al. Ann Hepatobiliary Pancreat Surg. 2019 Nov;23(4):372-376. https://doi.org/10.14701/ahbps.2019.23.4.372

NUT carcinoma is a rare malignant neoplasm characterised by recurrent NUTM1 rearrangements, initially reported in the midline. Recently, 10 cases of cutaneous NUT carcinoma with adnexal differentiation harbouring BRD3::NUTM1, NSD3::NUTM1, BRD4::NUTM1 or BRD3::NUTM2B fusions have been reported. Accordingly, ‘NUT adnexal carcinoma’ (NAC) has been introduced as a provisional tumour entity to the fifth edition of the WHO Classification of Skin Tumours.Aims: We report the histopathological, molecular genetic and epigenetic features of seven additional cases of NAC.Methods and results: The cohort consisted of four female and three male patients with a median age of 58 years. Follow‐up was available for six cases, and documented diffuse metastatic spreading leading to death at 18 months after diagnosis for one case. Histopathological examination in all cases revealed dermal/subcutaneous neoplasms composed of poorly differentiated cells with large irregular vesicular nuclei and at least focally prominent nucleoli. All cases showed areas of duct/gland formation. Using immunohistochemistry, all tumours showed diffuse NUT expression with co‐expression of SOX10 in five cases. P63 and P40 were diffusely positive in one case and confined to the periphery of the tumour nests in five cases. Molecular analysis showed BRD4::NUTM1 fusions (n = 3), BRD3::NUTM1 fusions (n = 3) and NSD3::NUTM1 (n = 1). Although being close to this latter group, methylation and transcriptional analysis revealed that NAC formed a unique cluster distinct from extracutaneous NUT carcinoma and NUTM1‐rearranged porocarcinoma.Conclusions: Our results further support the existence of primary cutaneous NAC and suggest that it may represent an entity distinct from extracutaneous NUT carcinoma.