The authors demonstrated that the FcγRIIIa acts on AR and PIP5Kα and also plays an important role in PCa progression and metastasis and the targeting of FcγRIIIa and PIP5Kα may provide a new therapeutic intervention. However, there are some issues:
Major comments:
1. The authors could also check the FcγRIIIa protein and mRNA expression in BPH tissues with comparison to primary and metastatic tumors. It will be important to examine the expression pattern of FcγRIIIa with AR and PIP5K1α in metastatic PCa and CRPC patients samples.
2. The authors should also comment on the cell proliferation ability of C4-2 / PC3 cells overexpressing FcγRIIIa.
3. Representative images should be provided in the Figure 3d showing that C4-2 /PC3 cells overexpressing FcγRIIIa gave rise to higher numbers of tumor-spheroids than that of controls.
4. The authors did not show whether overexpressing FcγRIIIa would further increase the migratory or invasive potential of benign prostate epithelial cells or C4-2 and PC3 cells.
5. Western blot shown in the Supplemental Figure 2 should be repeated again, as GAPDH expression seemed to be varied. Also, from the blot it is clear that PNT1A express high levels of FcγRIIIa than any other PCa cell lines. They should mention why is that so? Moreover, just to compare they should also include data for the RWPE1 cell line in this figure.
6. The authors have shown the inhibitory effect of anti-FcγRIIIa antibody on PCa growth in PCa cell line models and in PCa xenograft mice. However, there remains a question that as FcγRIIIa is functionally linked to PIP5K1α, does inhibition of PIP5K1α with ISA-2011B shows the similar effect? Also, how ISA-2011B in combination with anti-FcγRIIIa antibody affect in both (cell lines and mice xenograft) these cases?
7. The authors should also show the number of metastatic cells by using Alu-PCR based quantitative PCR analysis, and examine whether the anti-FcγRIIIa antibody has inhibitory effect on metastasis in mice xenograft experiment.
Minor comments:
1. Error bar is missing in figure 5(c).
2. The authors should repeat the blot in Figure 3a with a clearer blot, why are there two bands of FcγRIIIa?
3. Line number 359 has no meaning at all, sentence is incomplete.
4. Typo at line number 365.
5. The authors have mentioned that FcγRIIIa expression was found in the basal cells of epithelium of BPH tissues. So, does it mean that the luminal cells don’t express it?
6. The rationale is not clear that after evaluating the expression of FcγRIIIa in different cohort, why the authors have checked the expression of PIP5K1α and how FcγRIIIa is functionally linked to PIP5K1α.
7. The authors should also compare the CNAs of FCGR3A using primary versus metastasis PCa cohort.
8. The authors should mention that why they co-cultured PC-3 cells with U-937 cells to check the expression of FCGR3A.